Nanocomposite scaffolds have been developed in order to achieve better mechanical and physiological properties in bone tissue engineering applications. In this study, reinforced poly (3-hydroxybutyrate) (PHB) composite scaffolds made with different weight ratios of nanobioglass (0, 2.5, 5, 7.5, and 10 wt%) and various porosities (70, 80 and 90 wt% of NaCl) were prepared by the salt leaching process. The scaffolds were placed in a PBS solution and their weight loss was measured. The biocompatibility of samples was examined in vitro using the MG63 cell line by indirect test, cell proliferation, and alkaline phosphatase (ALP) assays. Cell attachment on the surface of the scaffolds was observed by scanning electron microscopy (SEM). The biodegradation results showed that increasing the volume fraction of porosity and concentration of bioglass nanoparticles enhanced the weight loss of the scaffolds. The cell study demonstrated that a certain concentration of nanobioglass (7.5 wt%) in the scaffolds can significantly improve cell proliferation, inducing better osteoconductivity, compared to that of the pure PHB scaffolds and controls. In addition, the SEM results showed high cell attachment on these samples. All these factors indicate that samples with 7.5 wt% nanobioglass are a promising scaffold for bone tissue engineering.


Significance Social media sites are often blamed for exacerbating political polarization by creating "echo chambers" that prevent people from being exposed to information that contradicts their preexisting beliefs. We conducted a field experiment that offered a large group of Democrats and Republicans financial compensation to follow bots that retweeted messages by elected officials and opinion leaders with opposing political views. Republican participants expressed substantially more conservative views after following a liberal Twitter bot, whereas Democrats' attitudes became slightly more liberal after following a conservative Twitter bot—although this effect was not statistically significant. Despite several limitations, this study has important implications for the emerging field of computational social science and ongoing efforts to reduce political polarization online. There is mounting concern that social media sites contribute to political polarization by creating "echo chambers" that insulate people from opposing views about current events. We surveyed a large sample of Democrats and Republicans who visit Twitter at least three times each week about a range of social policy issues. One week later, we randomly assigned respondents to a treatment condition in which they were offered financial incentives to follow a Twitter bot for 1 month that exposed them to messages from those with opposing political ideologies (e.g., elected officials, opinion leaders, media organizations, and nonprofit groups). Respondents were resurveyed at the end of the month to measure the effect of this treatment, and at regular intervals throughout the study period to monitor treatment compliance. We find that Republicans who followed a liberal Twitter bot became substantially more conservative posttreatment. Democrats exhibited slight increases in liberal attitudes after following a conservative Twitter bot, although these effects are not statistically significant. Notwithstanding important limitations of our study, these findings have significant implications for the interdisciplinary literature on political polarization and the emerging field of computational social science.


Abstract Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of Axtra® XAP 104 TPT as a zootechnical feed additive (digestibility enhancers) for poultry species. The additive contains three enzyme activities (endo‐1,4‐beta‐xylanase, protease and alpha‐amylase) produced by three different genetically modified strains. Viable cells and recombinant DNA of the strains producing the protease and amylase were not detected in the final product. Owing to the insufficient data, uncertainty remained on the presence in the additive of viable cells of the strain producing the xylanase. The results obtained in the genotoxicity and subchronic oral toxicity studies performed with the three fermentation products did not indicate safety concerns resulting from the fermentation products used in the formulation/manufacturing. However, uncertainties remain on the suitability of the test item used in the studies conducted with the xylanase; therefore, the Panel was not in the position to conclude on the toxicological potential of AXTRA ® XAP 104 TPT. Consequently, the Panel could not conclude on the safety of the additive for the target species, consumers and users. Owing to the uncertainty on the presence of viable cells of one of the production strains in the additive, the Panel could not conclude on the safety for the environment. The FEEDAP Panel concluded that AXTRA ® XAP 104 TPT is efficacious in chickens for fattening, chickens reared for laying and minor poultry species up to the point of lay at the level of 2,000 U xylanase, 200 U amylase and 4,000 U protease per kg feed. Owing to the lack of sufficient data, the Panel could not conclude on the efficacy of the additive for laying hens.


We analyze the crossover from Kondo to weak-link regime by means of a model of tunable bond impurities in the middle of a spin-1/2 XXZ Heisenberg chain. We study the Kondo screening cloud and estimate the Kondo length by combining perturbative renormalization group approach with the exact numerical calculation of the integrated real-space spin-spin correlation functions. We show that, when the spin impurity is symmetrically coupled to the two parts of the chain with realistic values of the Kondo coupling strengths and spin-parity symmetry is preserved, the Kondo length takes values within the reach of nowadays experimental technology in ultracold-atom setups. In the case of non-symmetric Kondo couplings and/or spin parity broken by a nonzero magnetic field applied to the impurity, we discuss how Kondo screening redistributes among the chain as a function of the asymmetry in the couplings and map out the shrinking of the Kondo length when the magnetic field induces a crossover from Kondo impurity to weak-link physics.


The marine riser is an important and indispensable part of the offshore oil industry as they are used to convey fluids from the sea bed to a platform or floater. Drilling risers are used during drilling of new wells, while production risers are employed for fields of production. The different concepts of riser configurations all possess different fields of application and characteristics. Steel pipes are the most common structure of riser systems, but also flexible and titanium pipes are utilized. Failure may have severe consequences and it is of crucial importance that a riser system is reliable and properly sized. Hence, estimation of extreme dynamic response of risers is necessary. The purpose of this study was to investigate how these loads can be estimated. The normal way to estimate extreme dynamic response is to carry out a full long term response analysis of the riser configuration. If the response of the structure is of a nonlinear nature the problem will be rather complex and time consuming. In this thesis the environmental contour line method is applied to a riser configuration. It is a simplified method used to estimate long term extremes response. The great advantage of this method is that the environmental loading and the response of the structure is decoupled. Thus the response analysis is only required for a set of design sea states. Determination of the short term extreme response distribution of the problem can be used to estimate the long term distribution of extreme response. This thesis comprises descriptions of riser configurations. The mathematical theory used for modeling the wave environment. The statistical methods utilized for long and short term analysis is presented. A thorough description of the environmental contour line approach is also presented. An analysis of a drilling riser configuration has been carried out for the semisubmersible drill vessel Scarabeo 8. The analysis is based on the procedure for the environmental contour line method. The riser configuration was modeled in SIMA, based on FE-program RIFLEX. Several nonlinear response analyses were carried out to identify the most critical sea state. The most critical case is analyzed through 24 analyses of 3 hour duration. The time series for the critical area of the riser with relevant response quantities where stored for post processing. Gumbel distribution where used in evaluation of the results. The bending moment and the axial force were estimated in the wave zone area of the drilling riser. Proper estimates of the response for the short term variability were accounted for by choosing a higher percentile value for the extreme value distribution. In this thesis the percentile values used were 0.85, 0.90 and 0.95. Normally 0.90 is considered a reasonable choice for most structural problems. To assess reasonable percentile values a full long term analysis should be performed. Although there are uncertainties, the contour line method is an approximate method. The numbers of observations, the choice of distribution, the parameter estimators, all illustrates this. There is a growing interest in development of reliable response calculations and this thesis might be viewed as a small contribution to that field.


Net representation, which provides a uniform semantics to a wide class of computational problems, such as numeric functions, logical systems, and models of dynamic and distributed systems, is reviewed. Using a uniform formalism of colored propositional nets, the methodology of net models is extended to represent Horn clauses, non-Horn clauses, and expert systems. It is shown that, using this formalism, tools can be built for expanding and partitioning knowledge-bases, and testing knowledge-base properties such as consistency, redundancy, and deadlocks.<<ETX>>


There has been a growing concern about obesity worldwide. We performed a review on the prevalence and trends of obesity among adults and children. We reviewed the data on the prevalence of adult obesity and being overweight from the Global Database on Body Mass Index on the World Health Organisation (WHO) Website and prevalence of children being overweight from the International Obesity Task Force website. Various databases were also searched for relevant reviews and these include PubMed, EMBASE, NHS CRD databases and Cochrane. The prevalence of obesity is high in many parts of the world. Generally, there is an increasing trend of prevalence of adult obesity with age. The peak prevalence is reached at around 50 to 60 years old in most developed countries and earlier at around 40 to 50 years old in many developing countries. Obesity is a major health concern. Appropriate strategies need to be adopted to tackle obesity which itself brings about significant disability and premature deaths. Further observation may be needed to see if the trend of prevalence abates or increases in the near future.


Cooperative Connected and Automated Vehicles (CAVs) require multiple disjunct In-Vehicle Networks (IVNs) to interact via wireless networks, making communication across vehicles prone to unnecessary queuing delays. Earlier studies have focused on updating wireless networks to integrate with IVNs, which would require substantial changes to the core and access network. In this work, we motivate an approach that moves complexity to the network edge, examining the potentials of mixing Time Sensitive Networking (TSN) wired networks and unmodified, best-effort wireless networks for Vehicle to Everything (V2X). Guided by a platooning use case, we present results from a simple proof-of-concept system simulation demonstrating the potentials of such an approach as well as the feasibility of performance evaluation in openly available simulation frameworks.


Participating in structured art programs is said to improve physical and mental health and social functioning of older adults including those with dementia. However, research on this subject is fairly new, and awareness of these programs is limited. Feedback for improved program design and delivery is also needed. In a partnership between UNC Greensboro and the Creative Aging Network, NC, we conducted a pilot project in North Carolina (USA) in 2011 to evaluate whether participating in a 10 week art exchange project called ARTmail improved mood and social connectedness among seniors. Although 60 seniors took part in the ARTmail program, most of them with a cognitive limitation, only 31 seniors took part in the evaluation, mostly because the legal representative of many cognitively limited seniors did not give permission for them to participate in the evaluation. We collected baseline and endline information on socio-demographic background, physical health, functional status; and depression, loneliness, and mood / connectedness scales appropriate for dementia and non–dementia groups. We also conducted qualitative interviews with selected site staff, volunteers, and participants, and performed field observations. Our findings suggested that among seniors with cognitive limitations, the mean of mood scores at endline was lower than at baseline, suggesting improved mood (approaching significance at the .10 level). A larger sample would likely have shown significant results. We conclude with a discussion of observations and suggestions from staff, volunteers, and participants, on experiences with the program and suggestions for improved implementation in future.


Karst caves are defined as solutional cavities >5–16 mm in diameter and discussion is limited to cases where such continuously extend to a surficial input or output or both. Three opposed sets of general genetic hypotheses ('the classical hypotheses') have been presented for such caves, arguing that the majority develop (1) in the vadose zone, (2) in the phreatic zone, or (3) proximate and parallel to a water table. It is contended here that vadose, phreatic, and water-table caves are all of common occurrence and may be linked in one genetic theory. A four state model is proposed in which ideal phreatic and water-table caverns are end members; in a given massif of soluble rock the state (cave type) that develops is a function of the frequency of fissures penetrable by groundwater. The water-table type is the high frequency end member. Fissure frequency increases with passage of time after onset of karstification and gradational features may also develop to modify phreatic types. Vadose caves may be of 'dr...


Ultrasonic
testing is a very important non-destructive method for testing components for
safety of nuclear power plants and other security and delicate parts in other
industries. Nowadays, thanks to the development of computer technology, it is
possible to simulate processes which occur during ultrasonic testing. That is
why numerical simulations are becoming an integral part of non-destructive
testing. Simulations are used to determine parameters of ultrasonic
examination, especially parameters of probes and scan plan and also in the analysis
of results. They are used in such cases, when it is necessary to verify
applicability of probes and methods. This verification could be provided on the
weld and test block which are not manufactured. It could be also provided on
defects, which are not manufactured in test block, but their presence is
possible in given weld joint. Simulations are very useful for verifying the
propagation of ultrasonic signal in given area (e.g. weld area). If movement of
probe is limited, possibility of whole volume scan should be verified.


The Learning Story approach to assessing and reporting children's learning is the dominant approach to assessment in New Zealand early childhood education largely due to endorsement by the Ministry Education and advocacy by academics and educational authorities. This article argues that regardless of the appeal of Learning Stories this approach should not be promoted as the only or best assessment practice. Educators, parents and children should be provided with choices, and a more multi-method or comprehensive approach taken to assessment. Two key rationales for a comprehensive approach presented in this paper are: (1) assessment has multiple purposes that require multiple tools rather than a one-size-fits-all approach; and (2) the effectiveness of assessment tools is contextually determined.


An approach to the acquisition of retrospective information on the radioactive pollution of the territories to organize the radioecological monitoring of environment was proposed. The approach is based on the application of the method of dendrochronoindication, allowing one to obtain the retrospective information on the delivery and accumulation of radioactive and other chemicals in the growth rings of the trees. Statistical processing and the analysis of the arrays of the multidimensional retrospective data was carried out using the principal components method. It was shown that the approach proposed allows one to reveal the emergency emissions that took place in the past at the enterprises of nuclear industry and make a well-grounded selection of the monitoring sites to establish the radioecological monitoring in the zones of nuclear industry impact.


The isolation, cloning, and sequencing of two full-length cDNAs corresponding to the root tip forms of the maize (Zea mays L. cv Clipper) annexins p33 and p35 are described. These are the first complete sequences for the widely reported doublet of plant annexins. The predicted sequences can be divided into four repeat domains characteristic of the annexin family, but Ca2+ binding by the type-II site typical of annexins would be predicted to occur only in repeats 1 and 4. This reduced number of sites is consistent with previously reported biochemical data indicating a high Ca2+ requirement for membrane association. Although the two annexins are very similar (80% amino acid identity), their genes are quite distinct, as demonstrated by their different 3[prime] noncoding regions and Southern blotting. The predicted sequences of the root tip proteins are very similar to regions known from peptide sequencing of the coleoptile proteins. Because a rather small gene family is indicated, the implication is that there may be less functional diversity than in animal cells. Furthermore, the sequence data clearly show that plant annexins form a very distinct group compared with those from other kingdoms.


This article discusses the brief but very meaningful work of the famous Armenian composer, music ethnologist, music pedagogue and musicologist Komitas Vardapet devoted to the Hungarian composer Ferenc Liszt. The work elaborates on the reasons why Komitas spoke about Liszt. The article discusses the scientifi c viewpoints of Komitas and his thoughts, which gain considerable project importance during the time.


Crowding on buses, trams and trains leads to a deteriorated performance of the public transport system through increased waiting times and vehicle bunching, and is naturally resented by its customers. In the past, i.e. in the absence of smart card ticketing system, crowding was difficult to measure in any detail and therefore to trace its impact on user behaviour, e.g. trip making, route and departure time choice by user characteristics. As a result stated preference surveys were the preferred instrument to measure its differential impact. Surprisingly, little research has been undertaken on the perception of the terms: full, crowed, overcrowded etc., used in such surveys. In this paper we describe an exercise, which made the perception the focus of its work. Using a set of images and a sample of users on crowded bus lines in Zurich we establish the likelihood that they will declare a bus full and link this to their socio-demographics.


This Guidance provides information on the effects of inflammatory bowel disease (IBD) in women of reproductive age with particular reference to contraceptive choices, fertility and pregnancy. For comprehensive advice on the management of patients with IBD, readers should refer to guidelines from the British Society for Gastroenterology.1 A key to the grades of recommendations, based on levels of evidence, is given at the end of this document. Details of the methods used by the Clinical Effectiveness Unit (CEU) in developing this Guidance, and evidence tables summarising the research basis of the recommendations, are available on the Faculty website (www.ffprhc.org.uk). Abbreviations used include: 5-aminosalicylic acid (5-ASA), body mass index (BMI), bone mineral density (BMD), combined oral contraception (COC), confidence interval (CI), copper-bearing intrauterine contraceptive device (IUD), Crohn's disease (CD), depot medroxyprogesterone acetate (DMPA), dual X-ray absorptiometry (DEXA), emergency contraception (EC), gastrointestinal (GI), incidence rate ratio (IRR), inflammatory bowel disease (IBD), levonorgestrel-releasing intrauterine system (IUS), odds ratio (OR), progestogen-only emergency contraception (POEC), progestogen-only pill (POP), anti-tumour necrosis factor-alpha (anti- TNF-a), ulcerative colitis (UC), venous thromboembolism (VTE), World Health Organization (WHO).


We introduce exotypes, user-defined types that combine the flexibility of meta-object protocols in dynamically-typed languages with the performance control of low-level languages. Like objects in dynamic languages, exotypes are defined programmatically at run-time, allowing behavior based on external data such as a database schema. To achieve high performance, we use staged programming to define the behavior of an exotype during a runtime compilation step and implement exotypes in Terra, a low-level staged programming language. We show how exotype constructors compose, and use exotypes to implement high-performance libraries for serialization, dynamic assembly, automatic differentiation, and probabilistic programming. Each exotype achieves expressiveness similar to libraries written in dynamically-typed languages but implements optimizations that exceed the performance of existing libraries written in low-level statically-typed languages. Though each implementation is significantly shorter, our serialization library is 11 times faster than Kryo, and our dynamic assembler is 3--20 times faster than Google's Chrome assembler.


ABSTRACT Private tutoring, or shadow education, has become a widespread phenomenon globally. Its growth can be attributed to the expansion of cram schools offering live and video tutoring. This study critically analyses students' perceptions of video-recorded classes. Specifically, it problematises students' preference for video-recorded classes by exploring their reasons for enrolment and their perspective on the benefits and shortcomings of video tutoring in a Hong Kong cram school. It adopts an exploratory sequential mixed-methods approach. Data were collected through classroom observations, student interviews and questionnaire. The findings reveal that students chose video-recorded classes mainly because of their flexibility of timeslots and locations. A critical discussion of the findings unveils students' contradictory attitude towards the presence of tutors in classrooms, their preference for passive learning and anxiety about tutor–tutee interactions. This study contributes to the growing literature of shadow education and offers implications for potential policy change in the private tutoring context.


Nutrient deficiency leads to a high fruit abscission rate and low yields of Sapindus mukorossi Gaertn. (Soapberry), which is one of the most widely cultivated biodiesel feedstock forests in China. Exogenous sucrose can provide a solution to nutrient deficiency and fruit abscission leading to low yields; therefore, it was applied to whole trees at two stages, 20 days before blooming (DBB stage) and before fruit abscission [days before fruit abscission (DBFA) stage]. Six sucrose concentrations, 0%, 1%, 1.5%, 3%, 5%, and 7%, were sprayed three times using a completely randomized block design with five replications and six treatments. 13CO2 labeling experiments were performed after the three sprayings. The results indicated that the 3% treatment had the highest yield, reaching 15.9 kg/tree. During the DBB stage, the 3% treatment significantly increased the inflorescence fructose and glucose contents 1- to 1.2-times and resulted in the highest fruit gibberellic acid, leaf indole acetic acid (IAA), fruit IAA, and fruit zeatin contents; however, it decreased the inflorescence abscisic acid (ABA) from 16 μg/g to 4 μg/g. The 1.5% and 3% treatments significantly increased the carbohydrate content and decreased the fruit ABA content to 30% to 50% of the control level during the DBFA stage. High-concentration sugar treatment (>3%) increased the nitrogen, phosphorus, and potassium contents, which decreased the calcium and magnesium contents. The 13C-dispatching ability of the inflorescence was three-times greater than that of leaves under the high-concentration sugar treatment during the DBB stage. Supplying 1.5% sucrose nearly doubled the allocation capacity during the DBFA stage. The source-sink nutrient migration pathway showed that leaf and fruit sugars were directly correlated with phosphorus. Fruit fructose and glucose contents affected the leaf mineral element contents.


Database is used for storing the data in an easy and efficient format. In recent days large size of data has been generated through number of applications and same has been stored in the database. Considering the importance of data in every sector of digitized world, it is foremost important to secure the data. Hence, database security has been given a prime importance in every organization. Redundant data entries may stop the functioning of the database. Redundant data entries may be inserted in the database because of the absence of primary key or due to incorrect spelled data. This article addresses the solution for database security by protecting the database from redundant data entries based on the concept of Bloom filter. This database security has been obtained by correcting the incorrect spelled data from query values with the help of edit distance algorithm followed by the data redundancy check. This article also presents the performance comparison between proposed technique and MongoDB database for document search functionality.


Splash is an essential process in interrill erosion because it detaches soil fragments from their substrate and transports them. However, splash measurements are difficult to interpret and relatively little is known about the influence of particle characteristics on the spatial distribution of splash. The objective of this work is to study the splash distribution of different size fractions for aggregated soils. We used a recently proposed theory for spatial distribution by splash to interpret experimental data on the radial distribution of soil fragments splashed by simulated rainfall. A laboratory device with five concentric rings was used to determine average splash lengths for 16 fragment size fractions (0.05 to >2000 μm) of four soils. Sieved soil (3- to 5-mm size fraction) was exposed to simulated rainfall at 29 mm h -1 and with a time-specific kinetic energy of 252 J m -2 h -1 . We interpreted the measured masses of fragments splashed into the different rings using an approximate solution of the exponential splash distribution theory applied to the experimental design. We demonstrated that the theory is valid for bulk aggregated soil as well as for individual fragment size fractions. The derived average splash lengths ranged from 4 to 23 cm, depending on the fragment size and soil. Splash lengths were greatest for soil fragments of 100 to 200 μm, and decreased for finer and coarser size fractions. Comparison of these findings with physically-based theory suggests that the coarser fragments, 50 to 2000 μm, are transported as single airborne particles, whereas the smaller ones, <50 μm, are transported in groups in splash droplets. This interpretation is consistent with observations reported in the literature.


AIM
To investigate whether patients with obstructive sleep apnea (OSA) are at risk of sedation-related complications during diagnostic esophagogastroduodenoscopy (EGD).

METHODS
A prospective study was performed in consecutive patients with OSA, who were confirmed with full-night polysomnography between July 2010 and April 2011. The occurrence of cardiopulmonary complications related to sedation during diagnostic EGD was compared between OSA and control groups.

RESULTS
During the study period, 31 patients with OSA and 65 controls were enrolled. Compared with the control group, a higher dosage of midazolam was administered (P = 0.000) and a higher proportion of deep sedation was performed (P = 0.024) in the OSA group. However, all adverse events, including sedation failure, paradoxical responses, snoring or apnea, hypoxia, hypotension, oxygen or flumazenil administration, and other adverse events were not different between the two groups (all P > 0.1). Patients with OSA were not predisposed to hypoxia with multivariate logistic regression analysis (P = 0.068).

CONCLUSION
In patients with OSA, this limited sized study did not disclose an increased risk of cardiopulmonary complications during diagnostic EGD under sedation.


Plesiosaurs are unique in being the only underwater fliers with four 'wings', and how the two pairs worked in relation to one another is a matter of some controversy. Newman's hypothesis of porpoising seems to provide a possible solution. Any discussion of plesiosaur locomotion must take into account the different modes of plesiosaur life: the long-necked forms were fish-eating surface paddlers and the short-necked were diving cephalopod feeders.


Cardiovascular diseases (CVDs) are a major cause of death worldwide, leading to increased medical care costs. To turn the scale, it is essential to acquire a more in-depth and comprehensive understanding of CVDs and thus formulate more efficient and reliable treatments. Over the last decade, tremendous effort has been made to develop microfluidic systems to recapitulate native cardiovascular environments because of their unique advantages over conventional 2D culture systems and animal models such as high reproductivity, physiological relevance, and good controllability. These novel microfluidic systems could be extensively adopted for natural organ simulation, disease modeling, drug screening, disease diagnosis and therapy. Here, a brief review of the innovative designs of microfluidic devices for CVDs research is presented, with specific discussions on material selection, critical physiological and physical considerations. In addition, we elaborate on various biomedical applications of these microfluidic systems such as blood-vessel-on-a-chip and heart-on-a-chip, which are conducive to the investigation of the underlying mechanisms of CVDs. This review also provides systematic guidance on the construction of next-generation microfluidic systems for the diagnosis and treatment of CVDs. Finally, the challenges and future directions in this field are highlighted and discussed.


The paper puts forth a timeline of the organization
known today as the Islamic State (IS,) from its founding by Abu
Musab al-Zarqawi in Iraq to its current territorial holdings in
Iraq and Syria under the leadership of Abu Bakr al-Baghdadi,
focusing on the involvement of the United States as a contributor
to the expansion of the organization. Beginning with Operation
Iraqi Freedom in 2003, the U.S. disrupted the fabric of Iraqi
society to the extent that IS was capable of attracting followers
and gaining territory in the country. The willful ignorance of a
developing insurgency coupled with the de-Ba'athification program
contributed to the success of al-Zarqawi's organization, and it
continued to operate openly in Iraq until 2007. After the U.S.
withdrawal from Iraq in 2011, it continued to affect the
development of IS by ignoring its resurgence in Syria. Aware of
IS's increasing role in the Syrian Revolution, the U.S. withheld
aid from moderate rebel groups, allowing IS to expand its influence
in the region. Finally, the paper assesses the future of U.S.
policy toward IS given the recent election of Donald Trump to the
presidency.


Essential facts [Figure: see text] Many patients admitted to hospital or receiving care in other settings, including their own homes, are recipients of one or more infusion therapies. Total parenteral nutrition, chemotherapy, parenteral antimicrobial therapy, pain relief and other infusion therapies are increasingly delivered in community settings. While the move away from hospital helps meet patients' lifestyles and clinical needs, it can have implications for patient care and safety.


Here, we reported two cases with hyperthyroidism who complained of myalgia and muscle cramps during treatment with methimazole tablets (or Thyrozol, the brand name). One case experienced muscle cramps after taking Thyrozol for 6 months, and by this time the patient's thyroid function had returned to normal. In the other case, pain caused by muscular cramps began after the patient took Thyrozol for two weeks and the patient's thyroid function had not returned to normal yet at the time. In both cases, pain caused by muscle cramps appeared while the patients were taking Thyrozol. The myalgia persisted in spite of a reduction in the Thyrozol dose, but was significantly relieved with the discontinuation of Thyrozol. Myalgia and muscle cramps did not recur after the patients were switched to methimazole ointment. There was a strong temporal association between oral administration of Thyrozol and pain caused by muscle cramps, which may indicate that myalgia and muscle cramps are adverse reactions of Thyrozol. Looking into the relevant literature on the topic, we explored in this report the possible mechanisms of the onset of muscle cramps associated with Thyrozol, and compared the adverse reactions of two different formulations of methimazole, intending to provide more clinical experience for the treatment of hyperthyroidism and the management of rare adverse reactions related to antithyroid drugs.


Microfluidic devices have been successfully used to recreate in vitro biological microenvironments, including disease states. However, one constant issue for replicating microenvironments is that atmospheric oxygen concentration (21% O2) does not mimic physiological values (often around 5% O2). We have created a microfluidic device that can control both the spatial and temporal variations in oxygen tensions that are characteristic of in vivo biology. Additionally, since the microcirculation is responsive to hypoxia, we used a 3D sprouting angiogenesis assay to confirm the biological relevance of the microfluidic platform. Our device consists of three parallel connected tissue chambers and an oxygen scavenger channel placed adjacent to these tissue chambers. Experimentally measured oxygen maps were constructed using phosphorescent lifetime imaging microscopy and compared with values from a computational model. The central chamber was loaded with endothelial and fibroblast cells to form a 3D vascular network. Four to six days later, fibroblasts were loaded into the side chambers, and a day later the oxygen scavenger (sodium sulfite) was flowed through the adjacent channel to induce a spatial and temporal oxygen gradient. Our results demonstrate that both constant chronic and intermittent hypoxia can bias vessel growth, with constant chronic hypoxia showing higher degrees of biased angiogenesis. Our simple design provides consistent control of spatial and temporal oxygen gradients in the tissue microenvironment and can be used to investigate important oxygen-dependent biological processes in conditions such as cancer and ischemic heart disease.


Summary: Hyphomicrobium sp. were grown on ethanol, acetate, 3-hydroxybutyrate and methanol. The specific activities of the following enzymes were measured in cell-free extracts of Hyphomicrobium strain x: ethanol dehydrogenase, acetaldehyde dehydrogenase, acetothiokinase, 3-hydroxybutyrate dehydrogenase, β-keto thiolase, citrate synthase, aconitate hydratase, isocitrate dehydrogenase, α-oxoglutarate dehydrogenase, succinate dehydrogenase, fumarate hydratase, malate dehydrogenase, isocitrate lyase, malate synthase, malate dehydrogenase (decarboxylating), phosphoenolpyruvate carboxylase, pyruvate kinase, phosphoenolpyruvate carboxykinase, phosphopyruvate hydratase and phosphoglycerate mutase. From a comparison of the specific activities of these enzymes in the different cell-free extracts, it was concluded that during growth of Hyphomicrobium sp. on either ethanol, acetate or 3-hydroxybutyrate, energy and reducing power is generated mainly by the tricarboxylic acid (TCA) cycle. Carbon is assimilated via the glyoxylate cycle with phosphoenolpyruvate carboxykinase functioning as the main gluconeogenic enzyme. The conversion of ethanol, acetate and 3-hydroxybutyrate to acetyl-CoA occurs by pathways previously reported in other micro-organisms.


The original aim of the project was to determine whether a non-poliovirus HEV could evolve to use the poliovirus receptor (PVR). A variety of methods were used to exploit aspects of the evolutionary capacity of viruses to achieve this goal. Although the aim was not attained, the investigation of recombinants between different HEVs yielded interesting results, which were pursued further. Two approaches were developed: in vitro generation of recombinant viruses and phenotypic analysis of such chimeras and the selection for recombinant viruses in vitro.

In vitro generation of reciprocal recombinants between the structural and the non-structural coding region of coxsackievirus A21 (CVA21) and poliovirus type 3 (PV3) was initiated. Transfected and passaged chimeras did not produce infectious virions.

Immunofluorescence analysis of VP1 protein expression suggested that the recombinants were not acytopathic. A series of assays were then carried out to investigate the nature of the defect. HeLa S10 translation/transcription reactions of the in vitro generated recombinants expressed the correct protein-processing pattern suggesting efficient processing occurred in vitro. Replication assays demonstrated that the chimeras were replication competent. Trans-encapsidation experiments were then carried out and preliminary results strongly suggested that the defect could lie at the packaging level.

Selection of recombinants in vivo, without predetermining the crossover sites, was also conducted. Under the conditions used, recombinant between CVA21 and PV3 impaired genomes and echovirus 7 (EV7) and PV3 impaired genomes proved to be unsuccessful. Characterisation of the impaired parental genomes used for the experiment needs to be carried out. However, recent reports of recombinants between Sabin polioviruses and HEV-C confirm the possibility of such a recombination event occurring and emphasize concerns regarding the success of the polio eradication program.


Dear Editor,

Gabapentin is an anticonvulsant and has been used to manage neuropathic pain. It was originally developed as an antiepileptic agent; however, it is now recommended as a drug of choice for the treatment of neuropathic pain. There is strong evidence that gabapentin is also effective in diabetic neuropathy and postherpetic neuralgia [1].

To the best of our knowledge, macular edema after use of gabapentin has not been reported to date. Therefore, we report a case of macular edema after gabapentin.

A 71-year-old man presented with a 1 day history of visual disturbance and metamorphosis in both eyes. The patient had taken oral gabapentin (Neurontin; Pfizer, New York, NY, USA) and oral methylprednisolone (Methylon; Alvogen, Seoul, Korea) for 8 days for treatment of postherpetic neuralgia. He had no other significant medical history, except hypertension controlled by oral medication. Best-corrected visual acuity (Snellen) was 0.4 (right eye) and 0.2 (left eye), and the intraocular pressure was 9 mmHg (right eye), 11 mmHg (left eye), as determined by non-contact tonometry. Both eyes had moderate cataract. Ophthalmic examination of the anterior segments revealed no other abnormal findings. Dilated fundus examination and spectral domain optical coherence tomography revealed macular edema and serous retinal detachment of macula in both eyes (Fig. 1A-1D). Fluorescence angiography revealed fluorescein dye pooling on the macula and multiple leakages in both eyes (Fig. 1E and 1F). The patient was advised to discontinue gabapentin, and the use of the drug was stopped.

Fig. 1

At the initial visit, macular edema and serous detachment on both eyes were observed by fundus photo (A, right eye [OD]; B, left eye [OS]) and spectral domain optical coherence tomography (C, OD; D, OS). On fluorescence angiography, fluorescein dye pooling ...

Four weeks after the initial visit, best corrected visual acuity improved to 0.9 (both eye). Fundus exam and spectral domain optical coherence tomography revealed markedly improved macular edema and serous detachment in both eyes (Fig. 1G-1J).

Gabapentin is an amino acid initially designed as a cyclic gamma-aminobutyric acid analogue with action as a gamma-aminobutyric acid agonist [2]. It also acts on different brain receptors by an as-yet unknown mechanism.

Common adverse effects of gabapentin include dizziness, fatigue, drowsiness, sexual dysfunction, weight gain, and peripheral edema [3]. Uncommonly, gabapentin causes blurred vision and diplopia [4]. Steinhoff et al. [5] reported that this drug has been linked with abnormal color perception and reduced contrast sensitivity due to an unknown mechanism. Gabapentin could also cause abnormal finding of visual evoked potentials and pattern electroretinogram [2]. It was suggested that toxic effects on the neuro-transmitter function of the optic nerve might be responsible.

Macular edema on optical coherence tomography after gabapentin has not hitherto been described. Using fluorescence angiography, the present patient was observed to suffer multiple chorioretinitis. Thus, it is possible that the macular edema was due to chorioretinitis. Herpetic infection can also induce chorioretinitis. However, the macular edema in the presented case was spontaneously improved after cessation of gabapentin and steroid, suggesting that chorioretinitis is not a sufficient explanation. Because the precise action mechanism of gabapentin is not known, it is difficult to deduce the mechanism of macular edema after the use of gabapentin. Further studies about the mechanism and frequency of macular edema after gabapentin are required.

In summary, we report macular edema occurring in a male patient receiving gabapentin therapy for postherpetic neuralgia treatment. The macular edema improved after discontinuing the use of the drug. If vision loss after the use of gabapentin occurs, it is prudent to identify macular edema. Gabapentin should be considered one of the potential causes of macular edema.


Social relationships have been seen as a contributor to happiness and well being since the time of Durkheim's classic study of suicide. For people with persistent mental illness, social relationships appear to be problematic. This study examined the contribution of social support and recreation companionship to life satisfaction among people with persistent mental illness. Clients from a community mental health program were surveyed on social support networks, recreation companionship networks, and life satisfaction. Findings indicated that minority group status, educational attainment, social support satisfaction, and recreation satisfaction were significantly related to life satisfaction. Neither the size of participants' social support nor recreation companionship networks were significantly related to life satisfaction. Multivariate analysis revealed that recreation satisfaction significantly predicted life satisfaction.


Antimicrobial peptides (AMPs) exert antimicrobial activity against Gram-positive and Gram-negative bacteria, fungi, and viruses by various mechanisms. AMPs commonly possess particular characteristics by harboring cationic and amphipathic structures and binding to cell membranes, resulting in the leakage of essential cell contents by forming pores or disturbing lipid organization. These membrane disruptive mechanisms of AMPs are possible to explain according to the various structure forming pores in the membrane. Some AMPs inhibit DNA and/or RNA synthesis as well as apoptosis induction by reactive oxygen species (ROS) accumulation and mitochondrial dysfunction. Specifically, mitochondria play a major role in the apoptotic pathway. During apoptosis induced by AMPs, cells undergo cytochrome c release, caspase activation, phosphatidylserine externalization, plasma or mitochondrial membrane depolarization, DNA and nuclei damage, cell shrinkage, apoptotic body formation, and membrane blebbing. Even AMPs, which have been reported to exert membrane-active mechanisms, induce apoptosis in yeast. These phenomena were also discovered in tumor cells treated with AMPs. The apoptosis mechanism of AMPs is available for various therapeutics such as antibiotics for antibiotic-resistant pathogens that resist to the membrane active mechanism, and antitumor agents with selectivity to tumor cells.


Kidneys from six male New Zealand white rabbits were fixed by perfusion, and the interstitium of all zones was studied by light and electron microscopy. The volume and amount of the basic components varied not only between cortex and medulla, but within each zone itself. Two main cell types were found in the cortical interstitium, the first appeared to be morphologically identical with a fibroblast, although it contained frequent surface depressions. The second cell type was of the mononuclear series, the most frequent of which was characterized by abundant free ribosomes and was frequently wrapped by processes of fibroblasts. Although collagenous fibrils, basement membrane-like material, and flocculent electron-dense material have previously been described in the interstitium of other animal species, this paper describes the presence and distribution of microfibrils approximately 150 A in diameter with electron-lucent cores throughout the entire kidney interstitium and discusses the distribution of globular deposits which may represent glycosaminoglycans in the various zones of the kidney.


BACKGROUND: Cataract is one of the reasons which causes impaired visual acuity (VA) of the eyes after penetrating keratoplasy (PK), which can be treated by cataract surgery after PK or triple procedure. Cataract surgery after PK has advantages that parameters of the eyes such as axial length, anterior chamber depth (ACD) as well as corneal curvature are stabilized after removing all sutures postoperatively, and intraocular lens (IOL) power can be calculated correctly. Therefore, postoperative VA will be improved significantly. In Vietnam, there have not been any study about cataract surgery after PK, therefore we conduct this research. AIM: To evaluate the outcomes of phacoemulsification cataract surgery following primary PK. METHODS: Non-randomized controlled intervention study. Ninteen eyes (19 patients) that underwent phacoemulsification plus IOL insertion after initial PK in Cornea department, Vietnam National Institute of Ophthalmology, from December 2013 to September 2014. RESULTS: All patients presented with reduced VA, including 17 eyes (89.9%) with VA ≤ 20/200, mean astigmatism was 7.9 ± 1.0 D. Clear corneal grafts in 16 eyes while corneal opacity was seen in 3 eyes. All eyes with cataract were diagnosed from grade 2. After cataract surgery, improved VA > 20/200 was achieved in 72.22% of cases. There was a markable reduce of postoperative astigmatism with 1.8 ± 0.8 D (p < 0.05). However, the immunologic graft reaction was presented in one eye, and two edematous corneas also reported after cataract surgery. After treatment, there was one cornea achieved its clarity. CONCLUSION: Phacoemulsification cataract surgery following initial PK showed good outcomes with improved postoperative VA, reduced astigmatism, and the ultimate graft survival rate was high.


Negative bias temperature instability is an important reliability problem in electronic industry. The Static RAM based structures within the microprocessor are mostly susceptible to NBTI because one of the pMOS transistors in the memory cell always has an input of Zero. Here we propose a technique called Recovery Boosting that provides both pMOS transistors in the memory cell to be bring into the recovery model. Evaluate the circuit-level design of coarse and fine grained recovery boosting techniques. Then conduct an architecture-level verification of the performances and the reliability of using area-neutral designs of physical register files and the issue queues. T his shows that Coarse Grained Recovery Boosting provides significant improvement in speed while having


The part of industrial ecology known as industrial symbiosis engages traditionally separate industries in a collective approach to competitive advantage involving physical exchange of materials, energy, water and by-products (Dounavis et al. 2015, Dounavis et al. 2016, Ravindran and Jaiswal 2016, Kourmentza et al. 2018, Keskisaari and Kärki 2018, Ayadi et al. 2018). The keys to industrial symbiosis are collaboration and the synergistic possibilities offered by geographic proximity. Industrial symbiosis includes initiatives in which two or more industrial entities develop both beneficial relationships and the circular economy (Chowdhury et al. 2018). Since, the symbiosis encourages the sustainable development and promotes the economy growth (de Jesus et al. 2018). This paper presents an online industrial symbiosis and circular economy platform created by a LIFE project (still ongoing) which aims to demonstrate the usefulness of a digital on-line platform at European level for the cataloguing, use and exploitation of industrial waste produced in a local area in order to improve the overall performance of industrial processes and circular economy in a local level. All this will happen both through the increased use of waste within the area itself and by the less dependence on the disposal of waste to be disposed of, taking into account the reduction of used raw materials and the reduction of waste itself. The platform will be created through the European LIFE M3P Project (Material Match Making Platform for the promotion of the use of industrial waste in local networks) which is still on-going and ends at the end of September 2019.


Introduction/purpose Aneurysms arising from the ophthalmic segment of the internal carotid artery (ICA) account for approximately 5% of all intracranial aneurysms. The Pipeline Embolization Device (PED) is a relatively new device available for treatment of these aneurysms. Here, we compare our experience with PED versus coil embolization in the treatment of unruptured ophthalmic artery aneurysms. Materials and methods A review of our prospectively collected patient log identified 106 patients who had undergone endovascular treatment of an unruptured ophthalmic artery aneurysm. Blinded to outcome, PED and coil patients were matched in a 1:2 fashion, respectively, based on aneurysm size. Matched analysis was carried out with marched t-test, Wilcoxon rank sum test, and McNamara's test as appropriate. P-values of ≤ 0.05 were considered statistically significant. Statistical analysis was carried out with Stata 10.0 (College Station, TX). Results After matching the patients in a 1:2 fashion, there were 20 patients treated with PED and 40 treated by coil embolization. There were no statistically significant differences in age, sex, average aneurysm diameter, or maximum aneurysm diameter. There were significant differences between the two groups in length of follow up, phase of treatment, baseline mRS, presentation, and neck size. Morbidity was 2.5% in the coiled cohort and 10% in the PED cohort (p = 0.255). Note, however, that in 1 of the 2 complications in the PED group, the patient was not compliant with their dual anti-platelet therapy. Immediate occlusion rates favored coil embolization as would be expected. However, recurrences were more frequent in the coiled group (22 vs 0%, p = 0.046). Conclusions This study suggests that complications may be more frequent with PEDs, but treatment may be more permanent as evidenced by the lower recurrence rate. Disclosures C. Durst: None. R. Starke: None. J. Gingras: None. H. Hixson: None. K. Liu: None. R. Crowley: None. M. Jensen: 2; C; Covidien. A. Evans: 2; C; Covidien, Stryker. J. Gaughen: 2; C; Covidien, Stryker, Microvention.


Equines perform tasks along humans, and there are evidences and controversies that they are able to discriminate between familiar and unfamiliar humans. This study assessed whether foals can discriminate between humans in terms of familiarity and human experience in equine handling. Daily, in the first two weeks of life, 30 foals went through a short section of gentle handling. After about four months, a human forced approach test was carried out by 4 evaluators varying in the familiarity aspect and experience with equine handling. Data was submitted to the McNemar test (P<0.05). In 66.7% of the assessments, the foals accepted the human approach, and among the positive cases, 60.0% were characterized by seeking contact with the evaluators. Among the foals that accepted the human approach, 97.5% also accepted tactile stimulation. No differences were found regarding the familiarity of the evaluators (P>0.05) or their experience in equine handling (P>0.05). The individual variation was evident, which indicates that we must work with personalized training techniques, in which the behavior of each individual is the main factor to be considered. Our results show that the adoption of good handling practices with foals favored their relationship with humans, and it is possible to assume that such practices can improve animal welfare, as well as the safety of the humans that will have contact with them in the future.


A new isolated strain of Sporobolomyces ruberrimus H110 was cultivated on technical glycerol as carbon source and effect of different temperatures and pH on the growth and pigmentation was studied. The maximum concentration of total carotenoid was 3.84 mgg -1 including torularhodin (3.70 mgg -1 ) and β-carotene (0.14 mgg -1 ) using 19oC at pH 6, but the highest amount of the maximum specific growth rate was obtained (µmax = 0.094 h -1 ) at 27oC. The growth yield (Yx/s ) was equal to 0.52 ± 0.01 g g -1 with a correlation coefficient value of 0.98.


We have developed simplified conical scanning telescopes using Holographic Optical Elements (HOEs) to reduce the size, mass, angular momentum, and cost of scanning lidar systems. This technology enables wide-angle scanning and three-dimensional measurements of atmospheric backscatter when used in airborne instruments, and high temporal and spatial resolution observations of atmospheric dynamic structure, including wind profiles from ground-based facilities. We deployed the Holographic Airborne Rotating Lidar Instrument Experiment (HARLIE) on the ground at the Department Of Energy's (DOE) central site in northern Oklahoma during their most recent Atmospheric Radiation Measurement (ARM) program Water Vapor Intensive Operating Period (WVIOP) in September-October 2000, in order to take advantage of the many coincident atmospheric measurements taking place at that time while collecting data with which to develop data reduction algorithms. We are evaluating the HARLIE technology and scanning techniques with an eye toward their application into other types of lidar systems, including Raman and Doppler lidar systems.


Reports investigations at Dun Ardtreck, a small D-shaped drystone strong-hold surrounded by an outer wall, which is located on the west coast of Skye, on a rock knoll with a sheer cliff. It could be one of a small group of sites with a high broch hollow wall but which were not circular towers. Considers the original height of the now ruined wall. Construction was probably in the first or second centuries BC and was followed by two distinct phases of occupation. In the second phase of occupation a wooden roundhouse with a raised floor may have been located within the higher-walled structure, although direct evidence is lacking. A fierce fire put an end to this occupation and the wall was pulled down. The ruins were re-occupied after a ramp containing Roman material was built against the entrance passage, facilitating easier access. Native pottery and Roman material suggest that occupation did not continue beyond the third or fourth centuries AD, however a sherd of E ware on top of layer implies that it went on at least until AD 500. Includes separately authored reports on:


The nuclear pore complex (NPC) is a macromolecular assembly embedded within the nuclear envelope that mediates bidirectional exchange of material between the nucleus and cytoplasm. Our recent work on the yeast NPC has revealed a simple modularity in its architecture and suggested a common evolutionary origin of the NPC and vesicle coating complexes in a progenitor protocoatomer. However, detailed compositional and structural information is currently only available for vertebrate and yeast NPCs, which are evolutionarily closely related. Hence our understanding of NPC composition in a full evolutionary context is sparse. Moreover despite the ubiquitous nature of the NPC, sequence searches in distant taxa have identified surprisingly few NPC components, suggesting that much of the NPC may not be conserved. Thus, to gain a broad perspective on the origins and evolution of the NPC, we performed proteomics analyses of NPC-containing fractions from a divergent eukaryote (Trypanosoma brucei) and obtained a comprehensive inventory of its nucleoporins. Strikingly trypanosome nucleoporins clearly share with metazoa and yeast their fold type, domain organization, composition, and modularity. Overall these data provide conclusive evidence that the majority of NPC architecture is indeed conserved throughout the Eukaryota and was already established in the last common eukaryotic ancestor. These findings strongly support the hypothesis that NPCs share a common ancestry with vesicle coating complexes and that both were established very early in eukaryotic evolution.


Clinical and laboratory findings recorded in 10 dogs naturally infected with Hepatozoon canis in the Aegean region of Turkey were reported. The diagnosis was made by finding H. canis gamonts within leucocytes in Giemsa- stained blood smears. H. canis parasitaemia level was calculated manually by counting 500 neutrophils in blood smears. Parasitaemia varied from 1% to 23% of the circulating neutrophils. Anorexia, fever, depression, weight loss, and lymphadenopathy are the main clinical signs in infected dogs. All dogs had microcytic normochromic anaemia; however, 7 of the dogs had neutrophilia, 1 had lymphopenia, 2 had monocytosis, 1 had eosinophilia, and 9 had thrombocytopenia. Abnormal serum biochemical values were hyperproteinaemia (7 of 10 dogs), hypoalbuminaemia (9 of 10 dogs), hyperglobulinaemia (7 of 10 dogs), increased serum alkaline phosphatase activity (2 of 10 dogs), and increased serum creatinine kinase activity (8 of 10 dogs). Concurrent infections such as Ehrlichia canis, Anaplasma phagocytophilum ,a nd Anaplasma platys were detected with a polymerase chain reaction test and 8 dogs had 2 or 3 of these concurrent infections.


We present a study of the energy levels in a FTO/TiO_2/CH_3NH_3PbI_3/Spiro solar cell device. The measurements are performed using a novel ambient pressure photoemission (APS) technique alongside Contact Potential Difference data from a Kelvin Probe. The Perovskite Solar Cell energy band diagram is demonstrated for the device in dark conditions and under illumination from a 150W Quartz Tungsten Halogen lamp. This approach provides useful information on the interaction between the different materials in this solar cell device. Additionally, non-destructive macroscopic DC and AC Surface Photovoltage Spectroscopy (SPS) studies are demonstrated of different MAPBI_3 device structures to give an indication of overall device performance. AC-SPS measurements, previously used on traditional semiconductors to study the mobility, are used in this case to characterise the ability of a perovskite solar cell device to respond rapidly to chopped light. Two different device structures studied showed very different characteristics: Sample A (without TiO_2): (ITO/PEDOT:PSS/polyTPD/CH_3NH_3PbI_3/PCBM) had ∼4 times the magnitude of AC-SPS response compared to Sample B (including TiO_2): (ITO/TiO_2/ CH_3NH_3PbI_3/Spiro). This demonstrates that the carrier speed characteristics of device architecture A is superior to device architecture B. The TiO_2 layer has been associated with carrier trapping which is illustrated in this example. However, the DC-SPV performance of sample B is ∼5 times greater than that of sample A. The band gap of the MAPBI_3 layer was determined through DC-SPS (1.57 ± 0.07 eV), V_oc of the devices measured and qualitative observations made of interface trapping by DC light pulsing. The combination of these (APS, KP, AC/DC-SPV/SPS) techniques offers a more general method for measuring the energy level alignments and performance of Organic and Hybrid Solar Cell Devices.


About one child in 68 is affected by the autism spectrum disorder (ASD), one of the most common neurodevelopmental disorders linked to intellectual disability, especially in males, intellectual disability being diagnosable in about 60–70% of autistic individuals. The biological bases of ASD are not yet fully known, but they are generally considered multifactorial, although many genes and genomic loci have been proposed to be possibly associated with this condition. In this report, we describe the case of a 14-year-old female Italian proband affected by ASD, carrying a novel ~ 270 kb interstitial microduplication, localized at the distal portion of the 4q13.1 region. The rearrangement was inherited from a mild symptomatic father and included a large part of the single EPHA5 gene, a receptor tyrosine kinase involved in the neural development, already indicated to be linked to ASD by previous Genome Wide Association Studies. This imbalance represents, to the best of our knowledge, the smallest duplication identified to date that only impacts the EPHA5 gene. We hypothesize that the duplication of this gene may alter EPHA5 expression and that this may impact the autistic phenotype of the patient.


Since the advent of tree-ring dating in the American Southwest, archaeologists have looked forward to the time when continuous chronologies would replace the inexact phase-based systems. The control of temporal variables is necessary for the description and explanation of culture change through time and space. This research moves the study of prehistoric culture change in the Black Mesa region of northern Arizona one step closer to the desired goal. The volume is organized into 13 chapters, with Steve Plog, a former director of the Black Mesa Archaeological Project (BMAP), serving as editor and primary author. Chapters one through four provide well written and useful introductory materials on project background, environment, methodology, and regional culture history. Chapter five, co-authored with Jeffrey Hantman, introduces one of the innovative and perhaps more controversial aspects of the project, which is the dating of sites lacking chronometric data by a type of multiple regression analysis based upon ceramic design attributes. Chapters six and seven, by Elizabeth Garrett and Margerie Green, respectively, provide useful discussions on the locus of ceramic production and the distribution of chipped stone raw materials. Mark Catlin then addresses the role of limited activity sites in the local settlement system. The final four chapters are broadly interpretive and, with the exception of a chapter on information exchange (based on a ceramic design study) by Michelle Hegmon, are all prepared by Plog; a wide variety of topics are addressed, including models of settlement, demographic growth patterns, regional exchange networks, resource use, and models of cultural change. The data base for the project is a survey of the eastern Peabody mine lease encompassing 120 km2 (46 mi2) of high elevation mesa country inhabited by the prehistoric Kayenta and historic Navajo peoples. A total of 796 sites representing 820 components spanning an occupation of several thousand years was recorded; the majority date to the A.D. 850-1150 time period, which represents the focal period of analysis. The multiple regression program is stated to provide dates accurate to plus/minus 19 years when a minimum sample of 21 decorated whiteware sherds are present. Utilizing this approach, 334 of the 820 components (40 percent) could be dated, while more traditional criteria were employed to date the remaining sites. It is unfortunate that this research did not utilize more fully the abundance of previously excavated BMAP sites to compliment surface survey data. While the continued quantification of ceramic design attributes on the sub-type level is to be encouraged, the multiple regression approach may not represent the best solution as a dating technique. As a further comment, the abundance of excavated data from the area also could have been employed more extensively to refine models of subsistence and settlement for the Black Mesa region. Plog dismisses homeostatic, environmentally based explanations of culture change and argues for an open systems model with an emphasis on social integration. He questions gradualist growth models of southwestern populations and, on the basis of Black Mesa data, proposes a more complex model of growth, decline, and abandonment. Several innovative methodologies for studying prehistoric population change are developed by Plog and his cohorts that must be evaluated by subsequent studies. They have nonetheless succeeded in providing the reader with some fascinating ideas and interesting directions for thinking about the prehistory of the Southwest.


A common premise in prior research is that trust increases over time in relationships. Through a meta-analysis of 39 studies, we find that the bivariate correlation between trust and relationship duration (i) is on average, positive and small and (ii) varies significantly across studies indicating the presences of unobserved moderators. We therefore build a theoretical framework to specify four different mechanisms – initial bias correction, change in relationship value, identification, and trust-based selection – that may affect the development of trust. We then argue that the relative strength of these mechanisms should influence whether trust increases, remains constant, or decreases over time.


For teaching English to speakers of other languages (ESOL) to be seen as having substantial impact, learning that occurs in the classroom must transfer to situations outside the classroom. Unfortunately, education research shows that transfer can be difficult to promote. Therefore, ESOL teachers may want to ensure that their classes are as conducive as possible to transfer. In the many ESOL contexts in which textbooks play a central role in classes, this will mean ensuring that the textbooks used help as much as possible to promote transfer. However, evaluating the potential of ESOL textbooks to help promote transfer may not be straightforward with existing published resources. Therefore, this article describes and demonstrates a new textbook evaluation tool that was designed based on key ideas in scholarly work on learning transfer and patterns in current ESOL textbooks. The aim is to provide a practical tool that teachers can use to evaluate the potential of ESOL textbooks to promote learning transfer.


Supplemental Digital Content is Available in the Text. The introduction of direct-acting antivirals for treating hepatitis C virus (HCV) infection has greatly improved cure rates. However, persons with past HCV infection who engage in high-risk behaviors can be reinfected. Surveillance data from the New York City (NYC) Health Department were used to detect and investigate individuals cured during January 2014 to December 2016 who had a subsequent positive RNA test (recurrence) by April 2018. Clinical interpretation of recurrence was obtained using provider interviews and review of medical records available through Regional Health Information Organizations. Among 6938 cured individuals, 209 recurrence events were detected (2.7 per 100 person-years). Investigations were completed for 62 (30%) events. Of 38 investigated events occurring less than 12 months postcure, 17 (45%) were relapses; of 24 events occurring 12 or more months postcure, only one (4%) was a relapse. Understanding the timing, frequency, and clinical interpretation of HCV recurrence will guide HCV prevention and elimination efforts for NYC.


Electrolytical layers of Ni-Mo alloys with polypyrrole, polytiofene and polyethylene were deposited on steel substrate (St3S, 4 cm2). After structural analyses of as quenched samples performed by X-ray diffraction it was noticed that the solid solution of Mo in Ni is observed. After annealing in an argon atmosphere the solid solution of Mo in Ni is becomeing more stable and crystalites are growing to the size of 200 – 300 Å. After annealing in an air atmosphere X-ray diffraction patterns show presence of phases: NiO, MoO, NiCO3, Mo2N. The unit cell parameters of solid solution after annealing are smaller than parameters of as quenched samples what means that the solid solution has been decomposing.


A major open issue in tropical meteorology is how and why some tropical cyclones intensify under moderate vertical wind shear. This study tackles that issue by diagnosing physical processes of tropical cyclone intensification in a moderately sheared environment using a 20-member ensemble of idealized simulations. Consistent with previous studies, the ensemble shows that the onset of intensification largely depends on the timing of vortex tilt reduction and symmetrization of precipitation. A new contribution of this work is a process-based analysis following a shear-induced midtropospheric vortex with its associated precipitation. This analysis shows that tilt reduction and symmetrization precede intensification because those processes are associated with a substantial increase in near-surface vertical mass fluxes and equivalent potential temperature. A vorticity budget demonstrates that the increased near-surface vertical mass fluxes aid intensification via near-surface stretching of absolute vorticity and free-tropospheric tilting of horizontal vorticity. Importantly, tilt reduction happens because of a vortex merger process—not because of advective vortex alignment—that yields a single closed circulation over a deep layer. Vortex merger only happens after the midtropospheric vortex reaches upshear left, where the flow configuration favors near-surface vortex stretching, deep updrafts, and a substantial reduction of low-entropy fluxes. These results lead to the hypothesis that intensification under moderate shear happens if and when a "restructuring" process is completed, after which a closed circulation favors persistent vorticity spinup and recirculating warm, moist air parcels.


Author(s): Diaz-Decaro, John Dave | Advisor(s): Godwin, Hilary A | Abstract: The costs of circulating infectious diseases in California and the need for better approaches to surveillance are major challenges for surveillance laboratories tasked with controlling and preventing the spread of disease. This is particularly true for respiratory pathogens and measles. Although vaccines are widely available for common respiratory tract pathogens as well as measles, outbreaks of both still occur, straining California local and state public health agencies on an annual basis. In the first part of this thesis, I critically evaluate the utility of multiplex molecular diagnostics for public health surveillance of respiratory pathogens and provide recommendations for the development of new assays that better meet the needs of the surveillance community. Next, I present a case study in which multiplex assays were used to study respiratory infections in nursing homes in California. This case study demonstrates the utility of multiplex assays for studying correlations between environmental contamination and human illness and suggests that this approach could be an effective tool for infection control in healthcare settings. Last, I present a study in which we modeled the epidemiological and economic impact of two recent measles outbreaks in California (the 2014-15 U.S. multi-state and the 2016-17 measles outbreak). The results of this study suggests that, at the county level, population density and the distance from the epicenter of the outbreak are the best predictors of contact counts and costs for these two measles outbreaks. In addition to providing insights into the true costs of prior measles outbreaks, this model also could be used prospectively by local health departments to better manage future outbreaks. Collectively, these studies provide important insights and tools for improving surveillance of respiratory pathogens, more effective controlling respiratory infections in healthcare settings, and decreasing costs of outbreaks.


This paper discusses the design and implementation of a video server which uses tertiary device as a source of media archiving. In order to handle the tertiary device in the framework of disk-based stream service model, an effective disk caching mechanism is devised together with stream scheduling and admission control mechanisms. The proposed system has been implemented on a general-purpose operating system and its design principles are validated the with real experiment results. The results guide us how streaming servers with tertiary storage should be configured in real environments.


Government agencies must make rapid and informed decisions in wildfires to evacuate people safely. However, current evacuation simulation tools for resource-strapped agencies largely fail to compare possible transportation responses or incorporate empirical evidence from past wildfires. Consequently, this study employs online survey data from evacuees of the 2017 Northern California Wildfires (n = 37), the 2017 Southern California Wildfires (n = 175), and the 2018 Carr Wildfire (n = 254) to inform a policy-oriented traffic evacuation simulation model. The simulation is tested for a hypothetical wildfire evacuation in the wildland-urban interface of Berkeley, California. The study focuses on variables including fire speed, departure time distribution, towing of items, transportation mode, GPS-enabled rerouting, phased evacuations (i.e., allowing higher-risk residents to leave earlier), and contraflow (i.e., switching all lanes away from danger). It was found that reducing evacuating household vehicles (i.e., to one vehicle per household) and increasing GPS-enabled rerouting (e.g., 50% participation) lowered exposed vehicles (i.e., total vehicles in the fire frontier) by over 50% and evacuation time estimates (ETEs) by about 30% from baseline. Phased evacuations with a suitable time interval reduced exposed vehicles most significantly (over 90%) but produced slightly longer ETEs. Both contraflow (on limited links because of resource constraints) and slowing fire speed were effective in lowering number of exposed vehicles (around 50%), but not ETEs. Extended contraflow can reduce both exposed vehicles and ETEs. It is recommended that agencies develop a communication and parking plan to reduce the number of evacuating vehicles, create and communicate a phased evacuation plan, and build partnerships with GPS-routing services.


The use of different solar activity indices like sunspot numbers, sunspot areas, flare index, magnetic fields, etc., allows us to investigate the time evolution of some specific features of the solar activity and the underlying dynamo mechanism. One of the problems when using these activity indices for some statistical analyses is the reliable determination of the maximum phases of different solar cycles which are generally characterized by a multi-peaked structure due to the presence of the so-called \emph {Gnevyshev gap}. The main aim of this work is to propose a general method, without the introduction of ad hoc heuristic parameters, to determine the duration of a given solar cycle maximum phase through a long-term solar activity index like the Monthly Smoothed Sunspot Number (SSN). The resulting extended solar maxima allows us to include the multi-peaked structure of solar cycles and further the proposed method allows us to predict the solar maximum duration of the current solar cycle 24.


HIV/AIDS in Latin America is concentrated among men who have sex with men (MSM). However, accurate estimates of engagement in HIV care in this population can be difficult to ascertain because many do not self-identify as MSM. Given evidence of decreased HIV transmissibility in the context of antiretroviral therapy (ART) adherence, identifying individuals not in care who are engaging in HIV transmission risk behavior is crucial for secondary prevention. Primary aims of this study were to examine engagement in care from testing to ART adherence among MSM using online social/sexual networking across Latin America, and whether individuals not in care at each step reported greater sexual transmission risk behavior than those in care. In the overall sample (n = 28,779), approximately 75% reported ever being tested for HIV, and 9% reported having received an HIV diagnosis. Among known HIV-infected individuals, 20% reported not being in care, 30% reported not taking ART, and 55% reported less than 100% ART adherence. Over one-third of HIV-infected individuals reported sexual HIV transmission risk behavior, defined as unprotected anal intercourse (UAI) with a male partner of different/unknown HIV serostatus in the past three months. HIV-infected individuals not engaged in care more often reported UAI compared to those in care (OR = 1.29; 95% CI = 1.01–1.66). Although not statistically significant, HIV-infected individuals not on ART more often reported UAI compared to those on ART (OR = 1.18; 95% CI = 0.94–1.47). Individuals who reported less than 100% ART adherence more often reported UAI compared to individuals with 100% adherence (OR = 1.55; 95% CI = 1.26–1.90). Findings demonstrate that a substantial portion of HIV-infected MSM in Latin America who are likely not virologically suppressed from lack of ART use or adherence report sexual HIV transmission risk. Tailoring secondary HIV prevention for MSM in Latin America who are not in HIV care or adherent to ART may be warranted.


Currently, the optimal sequential use of androgen receptor (AR) axis‐targeted agents and taxane chemotherapies remains undetermined. We aimed to elucidate the resistance status between taxanes and enzalutamide, and the functional role of the AR axis. Enzalutamide‐resistant 22Rv1 cells showed collateral resistance to taxanes, including docetaxel and cabazitaxel. However, taxane‐resistant cells showed no collateral resistance to enzalutamide; taxane‐resistant cells expressed comparable protein levels of full‐length AR and AR variants. Knockdown of both full‐length AR and AR variants rendered cells sensitive to taxanes, whereas knockdown of AR variants sensitized cells to enzalutamide, but not to taxanes. In contrast, overexpression of full‐length AR rendered cells resistant to taxanes. Consistently, the prostate‐specific antigen response and progression‐free survival in docetaxel chemotherapy were worse in cases with prior use of ARAT agents compared with cases without. Collateral resistance to taxanes was evident after obtaining enzalutamide resistance, and aberrant AR signaling might be involved in taxane resistance.


Density dependence occurs when the population growth rate, or constituent gain rates (e.g. birth and immigration) or loss rates (death and emigration), vary causally with population size or density (N). When these parameters do not vary with N, they are density-independent. Direct density dependence, where the population growth rate or gain rates vary as a negative function of N, or the loss rates vary as a positive function of N, is necessary but not always sufficient for population regulation. The opposite patterns, inverse density dependence or the Allee effect, may push endangered populations towards extinction. Direct density dependence is caused by competition, and at times, predation. It is detected observationally by analysis of abundance time-series; however, experimental field manipulations provide the most rigorous analytical methods for both detecting and understanding underlying mechanisms. Future directions include expanded and more detailed mechanistic field data integrated with more sophisticated population models.

Key concepts:

Direct density dependence occurs when the population growth rate varies as a causative inverse function of population size or density.

Inverse density dependence – the Allee effect – may occur in a small population, driving it extinct.

Direct density dependence is necessary but not always sufficient for a population to be regulated and may occur simultaneously with density independence.

The ecological mechanisms of density dependence are competition, and in some circumstances, predation (including parasitism and disease).

Density dependence is most commonly tested by examining the relationship between the population growth rate (or individual demographic rates) and population density, either observationally or experimentally.

Understanding density dependence and regulation within the context of a metapopulation – a population of local populations linked by occasional dispersal – faces major empirical challenges.

Recommended future research on density dependence includes detailed, mechanistic field observations and experiments, as well as modelling of complex dynamics in complex systems, such as metapopulations.

Keywords:

population ecology;
demographic rates;
Allee effect;
population regulation;
metapopulation


Temperature cycling tests are commonly used in the semiconductor industry to determine the number of cycles to failure and to predict reliability of the solder joints in the surface mount technology packages. In this paper, the thermomechanical fatigue of Pb40/Sn60 solder joint in a leadless ceramic chip carrier package is studied and temperature cycling test is simulated by using a finite element procedure with the disturbed state concept (DSC) constitutive models. The progress of disturbance (damage) and the energy dissipated in the solder joint during thermal cycling are predicted. It is shown that the disturbance criterion used follows a similar path as the energy dissipation in the system. Moreover, the comparisons between the test data and the finite element analysis show that a finite element procedure using the DSC material models can be instrumental in reliability analysis and to predict the number of cycles to failure of a solder joint. Furthermore, the analysis gives a good picture of the progress of the failure mechanism and the disturbance in the solder joint.


ABSTRACT The "rentier mentality" has been a key concept in rentier state theory since its development in the 1980s. It predicts that reliance on state patronage breaks the link between effort and reward, leads to low achievement orientation in economic life and makes citizens politically passive. Yet the rentier mentality hypothesis has hardly been empirically tested to date. This paper seeks to fill this gap through an analysis of a range of GCC survey data, including a previously unpublished survey of Saudi citizens' labour attitudes. A key descriptive finding is that many GCC citizens do indeed evince rentier attitudes when it comes to concrete life choices – but at the same time, a disproportionate share of them claim to be generally in favour of hard work, competition, and a small state. When it comes to politics, levels of interest are unusually high, but are coupled with high levels of loyalty and confidence in government. These results mean that while some aspects of rentier mentality are indeed prevalent, other attitudinal predictions of rentier state theory do not hold up – potentially because rentier states have adapted since the 1980s and used a range of social engineering tools to instil pro-business and patriotic beliefs on an abstract, ideational level.


Silver nanoparticles offer a possible means of fighting antibacterial resistance. Most of their antibacterial properties are attributed to their silver ions. In the present work, we study the actions of positively charged silver nanoparticles against both methicillin-sensitive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus. We use aberration-corrected transmission electron microscopy to examine the bactericidal effects of silver nanoparticles and the ultrastructural changes in bacteria that are induced by silver nanoparticles. The study revealed that our 1 nm average size silver nanoparticles induced thinning and permeabilization of the cell wall, destabilization of the peptidoglycan layer, and subsequent leakage of intracellular content, causing bacterial cell lysis. We hypothesize that positively charged silver nanoparticles bind to the negatively charged polyanionic backbones of teichoic acids and the related cell wall glycopolymers of bacteria as a first target, consequently stressing the structure and permeability of the cell wall. This hypothesis provides a major mechanism to explain the antibacterial effects of silver nanoparticles on Staphylococcus aureus. Future research should focus on defining the related molecular mechanisms and their importance to the antimicrobial activity of silver nanoparticles.


Conventional medical treatments of Parkinson's disease (PD) are effective on motor disturbances but may have little impact on nonmotor symptoms, especially psychiatric ones. Thus, even when motor symptomatology improves, patients might experience deterioration in their quality of life. We have shown that 3 years of active theatre is a valid complementary intervention for PD as it significantly improves the well-being of patients in comparison to patients undergoing conventional physiotherapy. Our aim was to replicate these findings while improving the efficacy of the treatment. We ran a single-blinded pilot study lasting 15 months on 24 subjects with moderate idiopathic PD. 12 were assigned to a theatre program in which patients underwent "emotional" training. The other 12 underwent group physiotherapy. Patients were evaluated at the beginning and at the end of their treatments, using a battery of eight clinical and five neuropsychological scales. We found that the emotional theatre training improved the emotional well-being of patients, whereas physiotherapy did not. Interestingly, neither of the groups showed improvements in either motor symptoms or cognitive abilities tested by the neuropsychological battery. We confirmed that theatre therapy might be helpful in improving emotional well-being in PD.


Variations in epitopes on structural proteins of four isolates of parainfluenza virus type 4 (PIV-4) and the Mr of polypeptides in these isolates were determined by radioimmune precipitation assay with monoclonal antibodies to parainfluenza virus type 4A (PIV-4A) and type 4B (PIV-4B). Three isolates antigenically resembled the prototype PIV-4A and the sizes of their structural proteins were 72K (HN protein), 61K (F0 protein), 61K (NP protein) and 40K (M protein). However, one virus isolate showed marked antigenic differences from both the 4A and 4B prototype viruses, particularly with regard to properties of the HN and F proteins. In addition, both the NP and F0 proteins of this isolate had a slightly increased Mr of 63K.


While the ACO concept gained momentum as a result of the healthcare reform legislation, the idea is nothing new. The Clinton health initiative included similar networks of providers, Accountable Health Partnerships, a proposal that went nowhere. So why should we worry about the current ACO model?


Virtual Learning Environment (VLE) is used to enhanced teaching and learning in Malaysia government public schools since 2012. Frog VLE has been used as a teaching and learning cloud-based internet platform in government schools which means that can be accessed anywhere and anytime. Currently main criteria for evaluating Frog VLE e-learning platform have focused on usability and acceptance. The sensory dimension of e-learning platforms is non-existent enough due to the rapid emerge the ideals of 'hyper-functionalism' nowadays. Therefore, in order to accommodate to future needs the focus on e-learning platforms need an aesthetic perspective instead of mainly addressing usability and function. So, there is need to produce the pleasurable design and aesthetic model of e-learning platform in order to increase the usage of the Frog VLE for teachers. This paper presented a research model for designing an aesthetic e-learning platform for Frog VLE.


In 2003 the Swedish parliament decided to incorporate maintenance support for the elderly within the framework of the state social insurance system. Maintenance support for the elderly entails that individuals who, due to too short a period of residence in Sweden, do not qualify themselves for a full guarantee pension and thus have the right to receive benefits after completion of an income test. A large proportion of these people previously received individually incometested social benefits. Maintenance support for the elderly and how it is perceived by the elderly is the focus of the study. The overall aim of the study is to gain knowledge about what it means for immigrants who moved in later life to be the subject of a transfer from a selective benefit system to one where more general principles apply. More specifically the aim concerns what it means for their possibilities for gaining access to social rights and what it means for their relationship with the Swedish welfare state. The study's empirical material consists of two parts. The first part contains register data from the social services register of the National Board of Health and Social Welfare and the social insurance register of the Swedish Social Insurance Board. The second consists of interviews with eleven foreign-born elderly persons who previously received social benefits and now receive maintenance support for the elderly. The analysis of the register data indicates that one-fifth of the target group actually includes people born in Sweden while the rest are immigrants arriving in Sweden in later life. For most of those in this latter group the maintenance support is their only source of financial support while it is a supplement for the Swedish-born elderly recipients. The results show that of those, who previously received social benefits and where the maintenance support is their only source of financial support, about onefifth received a smaller amount of benefit after the reform. The interview study indicates the existence of a gap between what the respondents express as needs of more individual considerations both in terms of the contact with the administrating authority and the maintenance support's monetary content and how the elderly perceive that these needs are provided for. In order to try to understand this gap the result was analysed by using a number of major theoretical concepts such as universalism, stigma and shame, and social citizenship, public identity and recognition. The conclusions of the study is that a comprehension of the gap can be found in the standardised design and administration of the maintenance support and in the socio-economic context that immigrants coming to Sweden in later life find themselves in.


This article draws on lessons from the Bracero Program to examine the problematic ideologies of race and citizenship that circulate in the alternative food movement today. It argues that a worker-centered transnational solidarity movement will better address the inequities and vulnerabilities that farmworkers continue to face than the conscious consumerism of the alternative food movement with its racialized discourse of Jeffersonian agriculture and its neoliberal investment in anti-obesity rhetoric.


We investigate named entity recognition in Greek legislation using stateof-the-art deep neural network architectures. The recognized entities are used to enrich the Greek legislation knowledge graph with more detailed information about persons, organizations, geopolitical entities, legislation references, geographical landmarks and public document references. We also interlink the textual references of the recognized entities to the corresponding entities represented in other open public datasets and, in this way, we enable new sophisticated ways of querying Greek legislation. Relying on the results of the aforementioned methods we generate and publish a new dataset of geographical landmarks mentioned in Greek legislation. We make available publicly all datasets and other resources used in our study. Our work is the first of its kind for the Greek language in such an extended form and one of the few that examines legal text in a full spectrum, for both entity recognition and linking.


In 2001 the Singapore Institute of Management (SIM) in collaboration with the British Open University (OU) ran a successful presentation of the Level 1 Technology Course 'You, Your Computer and the Net'. The 30 point foundation level course was delivered to 9,000 students in 13 UK regions and simultaneously to a cohort of 200 students in Singapore. One of the striking factors about the results of this course was the difference in retention and ultimately the final pass rates of the two cohorts of students. This paper will describe the course and its delivery in the two countries, attempting to offer some explanations for this discrepancy in drop out rates using a cross cultural perspective.


The difficulties of constructing a three-dimensional, continuous force-free magnetic field in the solar corona are investigated through a boundary value problem posed for the unbounded domain external to a unit sphere. The normal field component Bn and the boundary value αb of the twist function α on the unit sphere, combined with the demand for a vanishing field at infinity, do constitute sufficient conditions for determining a solution if it exists, but Bn and αb cannot be prescribed independently. An exhaustive classification of the admissible (Bn,αb)-pairs is developed, using the topological properties of the α flux surfaces implied by their footprints described by the constant-αb curves on the unit sphere. The incompatibilities arising from boundary conditions contradicting the field equations are distinguished from the interesting one of (Bn,αb) being, in principle, admissible but requiring a weak solution describing a force-free field containing inevitable magnetic tangential discontinuities. This particular incompatibility relates the boundary value problem to the Parker theory of spontaneous current sheets in magnetic fields embedded in electrically perfectly conducting fluids. Our investigation strategically skirts around some important but formidable mathematical problems to arrive at physically definite conclusions and insights on the construction of force-free fields, both in the practical task of modeling coronal magnetic fields with magnetopolarimetric data and in the basic understanding of the Parker theory. Two specific demonstrations of (Bn,αb) are given to illustrate circumstances under which a continuous solution to the boundary value may or may not exist.


A self-paced intermediate algebra course with computer tutorial software as the mode of instruction was implemented at a private four-year liberal arts college in the fall semester of 1998. The course was designed to provide a review of algebra for students whose mathematics placement test scores indicated that they were not prepared for college level mathematics. The purpose of his qualitative study was to investigate the impact of this computer assisted instruction (CAI) on students' knowledge of mathematics prerequisite to college algebra. Case study methodology was used to discover and describe (1) the impact of the tutorial on the students' ability to solve algebra problems successfully, (2) the experiences students have using CAI, (3) how this mode of instruction compares to that in previous mathematics courses, and (4) the strengths and weaknesses of such a course.
The subjects in the study consisted of 12 students who were recommended for placement into intermediate algebra during summer placement testing and registration. During the data collection process, the following groups emerged: five participants, two drop-outs, three college algebra students, and two nonparticipants. Data were collected through interviews of four participants, participants' scores from tutorial sessions and chapter tests, and an interview with one college algebra student. Correspondence with academic advisors, dropouts, and college algebra instructors also provided data. Interviews were audio taped and transcribed. These transcriptions were reviewed by the participants. The data were coded and analyzed by the researcher and a case study report was developed.
The main points concerning CAI that emerged from the study were the benefits to students of immediate feedback from the computer, the value of interaction with the computer as a means of learning mathematics, and the advantage of individualized instruction. The study indicated that the primary weaknesses of the course were the self-paced format and the lack of academic credit for course completion. The strengths of the course included clear and consistent instruction, promotion of student involvement, and instructive feedback. Recommendations for the college's intermediate algebra course included the continued use of CAI, the addition of a classroom component, and the award of credit for course completion.