: Determination of creatinine clearance is the most commonly used method to evaluate renal function, requiring collection of urine from a given period of time, usually 24 hours. Cockcroft and Gault developed a formula to estimate this parameter without urine samples, however some authors have shown the low reliability of this and similar nomograms. The present study is an attempt to evaluate the differences between the laboratory determination of this parameter and its evaluation using Cockcroft's equation. The study included 24 patients who had creatinine clearance determined through biochemical methods and with the formula proposed by Cockcroft. Mean clearance in the first instance was 81.4 mL/min and 65.5 mL/min in the second one. The estimated mean difference in creatinine clearance obtained by both methods was 16.4 mL/min. A significant difference between clearance determinations was found using the above methods and therefore it is concluded that the values obtained with Cockcroft's formula are hardly reliable since the method tends to subestimate creatinine clearance. Also, two new formulas were developed which correlate better with the results obtained in our series. To conclude, we recommend that creatinine clearance should be measured at the laboratory using serum and 24-hour creatinine determination.


This paper explores and estimates idiosyncratic and global factors that affect the evolution of sovereign spreads in emerging economies, with an emphasis on the Chilean case, for the period from January 1998 to September 2005. We find that a small number of global factors explain a large part of the sovereign spreads' variability. In line with certain differentiation of international investors toward investment-grade economies, global factors seem to account for a smaller proportion of the sovereign spreads' variability in these economies. In addition, we find that the recent reduction in Chile's country risk can be explained by the evolution of both the idiosyncratic factor determined in principle by robust macrofinancial fundamentals and—mainly—of the global factors associated with world growth projections.


Snakes are purported to drink by sucking water into their mouths and then compressing the oral cavity to force water into the oesophagus. Video recordings of drinking behaviour in 23 snakes representing 14 species from three families, combined with simultaneous recordings of water volumes consumed, show that all the snakes vary widely in the amount of water taken in when drinking. This variation is not correlated with kinematic events. Kinematic recordings and indirect measurements of water flow suggest that moving water into the mouth can be decoupled from the processes that move water into the oesophagus and that, infrequently, water may continue flowing into the mouth during both opening (suction) and closing (presumed compression) of the mouth. Drinking in snakes is not a simple, stereotyped behaviour. Different snake species differ in both drinking kinematics and water inflow patterns. Vertical excursions of the mandible are smallest in booids and larger, but highly variable, in different viperids and colubrids. Cyclic movements of the tongue seen in booids are not evident in viperids or colubrids. All the snakes usually take in water at rates far below their potential maximum rate. Although drinking is apparently achieved by suction, a single model cannot explain all water movement patterns in snakes. At a practical level, functional morphological studies of drinking in snakes (and possibly many other animals) must demonstrate that fluid flow actually correlates with kinematic events. Without such an empirical demonstration, interpretation of other measurements (pressure, movement, etc.) is unlikely to produce meaningful models.


Pulmonary epithelioid hemangioendothelioma (PEH) is a rare vascular tumor of borderline or low-grade malignancy, and its prognosis is unpredictable. Herein, we describe the case of a 47-year-old asymptomatic female with a diagnosis of multinodular PEH. During a 7-year follow-up, the nodules with large size and high 18F-fluorodeoxyglucose uptake in the initial study showed progression with increasing sizes; however, most small nodules (size < 1 cm) demonstrated spontaneous regression with peripheral rim or nodular calcification. The patient underwent surgical resection for an enlarged nodule. Of note, it is unusual for an individual to have mixed progression and regression concomitantly, which may be helpful in predicting the prognosis.


Background Cardiovascular patients who quit smoking significantly reduce their risk of a new event compared with those who continue smoking. Smoking is related to poor quality of life (QoL).Aim The purpose of the present study was to examine the extent to which smoking cessation leads to changes in QoL in coronary patients.Material Smoking patients (N = 100) and ex smokers patients (N=100) with coronary heart disease were included. Methods At baseline, sociodemographic and clinical characteristics were established. Generic QoL as well as smoking status were assessed using SF-36 (SF-36 Health Survey) questionnaire.Results No main differences were found between quitters and smokers in terms of improvement in QoL. In fact, some subgroups reported a poorer QoL after smoking cessation: Younger patients reported higher vitality and physical functioning scales, and patients who had low nicotine dependency reported lower generic QoL.Conclusions A high level of nicotine addiction is an important negative predictor of QoL.


Routine histopathological examination of hernia sac in adults remains a controversial topic. We undertook a retrospective study to assess possible clinical benefits of pathological examination of hernia sac specimens. Our pathology database between 1992 and 2020 was searched for adult specimens submitted as hernia sac. The clinical and pathological data of patients with abnormal histopathological findings were reviewed. There were 5424 hernia sac specimens (3722 inguinal, 1625 umbilical, and 77 femoral), 32/5424 (0.59%) with malignancies (28 epithelial and 4 lymphoid) and 25/32 were located in the umbilical region. Twelve out of twenty-five malignancies (48%) presented as primary clinical manifestations of the diseases (5 GI tract carcinomas, 5 gynecological tract carcinomas, and 2 lymphoid neoplasms); and 13/25 (52%) specimens were involved by previously known tumors (8 gynecological carcinomas, 3 colon carcinomas, 1 breast carcinoma, and 1 lymphoma). Among the 7 inguinal hernia sacs with malignancies, 3 (42.9%) were primary presentations of the tumors (2 prostatic carcinomas, 1 pancreatic carcinoma), and 4 (57.1%) were previously known tumors (2 ovarian carcinomas, 1 colon carcinoma, 1 lymphoid). Benign lesions were 12/5424 (0.22%), including 7 adrenal rests, 4 endometriosis, and 1 inguinal sarcoidosis. The incidence of hernia sacs with malignancies was 32/5424 (0.59%), most commonly from nearby organs in gynecological tract. However distant metastases from breast were also present. Near half of the hernia sac with malignancies (15/32, 47%) presented as the first clinical manifestation. Routine histopathological examination of hernia sac in adults is recommended, since it may provide important clinical information.


The concept and organization of inpatient psychotherapeutic treatment as focal psy chotherapy has proven helpful in many cases, llie focus takes on an integrative and guid ing function since various therapeutic activities are oriented toward the same focus. The focus recurs in varied thematic guises in different areas of therapeutic interaction. Among patients with so-called structural disturbances, the focus does not usually pick up a focal conflict but the typical disturbances of the self and object relations. Considerations of method retreat into the background of the thoughts and actions of all those involved in treatment. In their place, treatment is considered as a focally determined process of ther apeutically conscious social interaction based on the individual patient and his or her par ticular disturbance.


ABSTRACT Continental European jurisdictions have introduced corporate opportunities rules inspired by Anglo-American law. Despite a certain degree of homogeneity in substantive law, their monetary remedial systems still differ in common law and civil law jurisdictions. These differences matter because of the deterrence function connected to corporate opportunities remedies – deterrence being the core of fiduciary law. This article explains the divergences embedded in different legal traditions within a law and economics framework. It looks at potential developments of corporate opportunities remedies, drawing inspiration from a sample of European jurisdictions. Whereas UK law uses a vast array of remedies with high potential of deterrence and great flexibility in their application, civil law remedies are fewer, weaker and less flexible than the common law ones. However, the deterrence potential of civil law corporate opportunities remedies could be increased either through the introduction of criminal sanctions or future development of punitive damages doctrines.


Abstract During the past year; there has been continued incremental progress in the ratification and implementation of international conventions, particularly the 1970 UNESCO Convention. Countries of origin, particularly Italy and Greece, have become even more active in seeking the restitution of looted antiquities, as with the ongoing trial of former Getty curator Marion True and agreements with several U. S. museums for the return of numerous artifacts. The litigation concerning Iranian artifacts in various U. S. institutions has become even more complex, however, and the outcome is still uncertain. Finally, United States case law, particularly in the western part of the country, is pointing out some of the weaknesses in federal laws designed to protect archaeological sites and artifacts on federal land.


This paper describes the implementation of a flow-injection solid phase spectroscopy (FI-SPS) system with photochemically induced fluorescence (PIF) in micellar medium for the determination of metsulfuron-methyl (MET). The micelles containing a strongly fluorescent photoproduct generated after UV irradiation of the herbicide are strongly retained on C(18) silica gel filling the flow-cell placed in the detection area and the photoproduct is monitored at 323 and 378 nm for excitation and emission wavelengths, respectively. The solid support is easily regenerated for subsequent sample injections (at least up to 500 cycles tested). The system was calibrated for two injection volumes, 300 and 1000 microl. The detection limits and relative standard deviations were 0.71 and 0.14 ng ml(-1), and 4.5 and 3.3% for each injection volume, respectively. The system shows a very high throughput, 34 (300 microl) and 36 (1000 microl) analysis per hour. The optosensor was successfully applied to the herbicide determination in river, well and irrigation waters (recovery ranges from 96.0 to 106.0%).


Background: Understanding end-of-life (EOL) and palliative care continues to grow. However, little attention has been paid to the experiences, preferences, and needs of older lesbian, gay, bisexual, transgender, and queer (LGBTQ) women. While some universal expectations or preferences at EOL exist, this population may not receive adequate or appropriate attention or reporting of unique EOL issues and experiences. Objective: Systematically search for and narratively review existing evidence concerning the expectations, preferences, and needs for palliative and EOL care of LGBTQ older women. Design: A comprehensive literature review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Articles reporting needs, experiences, and perspectives of palliative care and EOL care among LGBTQ older women were evaluated. Measurements: Articles published between 1996 and 2019 were retrieved from PsycINFO, MEDLINE, Cochrane Library, Academic Search Complete, AgeLine, CINHAL, PubMed, LGBT Life, SocINDEX, Women's Studies International, Joanna Briggs Institute, and Open Grey. Results: A total of 16 articles were included. Articles described several concerns for the overall LGBTQ population; however, additional issues and experiences specific to older LGBTQ women were also identified, including vulnerability associated with isolation and poverty, women's social needs and support networks, and preferences for complementary care. Conclusion: There remains a need for further research with older LGBTQ women concerning palliative and EOL care, particularly around preparation for EOL and preferences for support. Inclusion of diverse populations in terms of sexual and gender identification are needed to fully understand how to provide appropriate and preferred support.


ABSTRACT In this article, we present the GeoCorpora corpus building framework and software tools as well as a geo-annotated Twitter corpus built with these tools to foster research and development in the areas of microblog/Twitter geoparsing and geographic information retrieval. The developed framework employs crowdsourcing and geovisual analytics to support the construction of large corpora of text in which the mentioned location entities are identified and geolocated to toponyms in existing geographical gazetteers. We describe how the approach has been applied to build a corpus of geo-annotated tweets that will be made freely available to the research community alongside this article to support the evaluation, comparison and training of geoparsers. Additionally, we report lessons learned related to corpus construction for geoparsing as well as insights about the notions of place and natural spatial language that we derive from application of the framework to building this corpus.


This paper proposes a method of installing phasor measurement units (PMU) in multiple stages. The scheme is developed on the concept of bus tier system and provides an optimal number of PMUs with a strategy to install them in a particular stage. The synchronized phasor measurements from the PMUs placed by the proposed method are used in developing a hybrid state estimator (HSE). The HSE estimates the voltage phasor at all the buses of a power system with a limited numbers of PMUs in steady state as well as in the presence of disturbances even in that part of network which is unobservable through PMUs. Performance of the proposed phased installation scheme for HSE is evaluated on the number of standard test system and the simulation results shows an improvement in the accuracy of the estimated states as compared to the existing methods in the literature.


This article describes the methods used within the Archaeology of Architecture in Romagna research project and in particular the structure and principles of the database. The results obtained in the following fields are illustrated: transformation of the architecture of churches and castles, medieval building technologies, ancient measuring standards, and clients. We selected 47 sites, including 7 ecclesiastical and 40 defensive buildings (castles). In the urban landscape the research focused on one of the most significant ecclesiastical buildings in Ravenna: the church of Santa Croce. Expanding into the field of monumental landscaping, a new project focused on a census of moulds and the forms of ancient building materials (campioni mensori) in northern Italy. In medieval Italian communes craftsmen and traders had to follow many rules to ensure the honesty and integrity of trades. All the members within the same administrative district had to use same systems of linear measurements and weights. Samples of these were exhibited on the walls of public buildings. Our methodological approach for the study of a monument uses the ancient measurements in order to understand the identity of clients, the origin of the workers and the chronology of architectures. The last part of the article suggests future goals of the research project.


Hot isostatic pressing (HIP) is the established procedure to process Udimet 700 Powder by Powder Metallurgy (P/M) techniques. In this paper the method of hot explosive pressing (HEP) was applied. Its main feature is the direct method of explosive pressing. To avoid any reaction beforehand, the heating device and the explosive compaction device are separated and brought together very rapidly just a few milliseconds before ignition of the explosive charge. Udimet 700 bulk samples are obtained and investigated by metallographic and mechanical testing.


A transformation towards sustainable food production requires improved circular nutrient management. Urban organic waste contains relevant nutrients and organic matter, yet only 4% of global urban nitrogen (N) and phosphorus (P) sources are presently recycled. One recycling approach is the composting of urban wastes for urban horticulture. We characterized compost from various urban waste fractions and assessed their fertilizer value in a pot trial with lettuce plants. Seven treatments were investigated: food waste vermicompost with coir and paperboard bedding material, thermophilic compost from green waste and human feces, two references with mineral fertilization and a sand control. The lettuce yield and total uptake of P, potassium (K), calcium (Ca), and magnesium (Mg) were highest in plants grown in coir-based vermicompost. The fecal compost led to the highest shoot P and K content, but the shoot uptake of Ca and Mg were lower than in the other treatments. All composts required additional N for lettuce growth. In conclusion, urban waste-derived vermicompost and fecal compost demonstrate a high delivery rate of plant-available Ca, Mg, P, and K. Research is needed on macronutrient availability and alternative N sources for the substitution of synthetic fertilization. These findings support the production of urban waste composts, furthering efforts in nutrient recycling.


Background: Obstructive sleep apnoea can be considered as a hidden killer in our society due to lack of awareness and research, despite its multiple comorbidities and complications like diabetes, cardiovascular diseases and sudden deaths. Studies are showing conflicting results for relationship of apnoea and glucose metabolism. The objective of this study was to explore a possible association between obstructive sleep apnoea and glucose metabolism in our local population. Methods: Potential case subjects were scrutinized from Sleep laboratory. Verbal and written informed consent, physical examination, history and Epworth sleep scale score calculation was carried out. After overnight polysomnography, 50 confirmed sleep apnoea subjects were selected. 50 matched controls, without any sleep related complain were selected after informed consent, history and physical examination. Fasting blood sample was collected from all. Blood sugar levels were compared in both groups. Comparison was also done with severity of apnoea in mild, moderate and severe apnoea patients. Results: The mean fasting blood sugar was significantly higher in cases (p=0.007). Frequency of population with impaired glucose metabolism was also significantly higher in OSA group (p=0.001). Disturbed glucose metabolism was also found to be associated with severity of apnoea, it was 32% in controls while 50%, 76.5% and 61.9% in mild, moderate and severe apnoea respectively. Conclusions: Our findings suggest that obstructive sleep apnoea is associated with a higher disturbance in glucose metabolism; it is also associated with severity of OSA in our population.
Pak J Physiol 2018;14(4):5–8


: Although lung cancers with activating mutations in the epidermal growth factor receptor (EGFR) are highly sensitive to selective EGFR tyrosine kinase inhibitors (TKIs), these tumors invariably develop acquired drug resistance. Host stromal cells have been found to have a considerable effect on the sensitivity of cancer cells to EGFR TKIs. Little is known, however, about the signaling mechanisms through which stromal cells contribute to the response to EGFR TKI in non-small cell lung cancer. This work examined the role of hedgehog signaling in cancer-associated fibroblast (CAF)-mediated resistance of lung cancer cells to the EGFR TKI erlotinib. PC9 cells, non-small cell lung cancer cells with EGFR-activating mutations, became resistant to the EGFR TKI erlotinib when cocultured in vitro with CAFs. Polymerase chain reaction and immunocytochemical assays showed that CAFs induced epithelial to mesenchymal transition phenotype in PC9 cells, with an associated change in the expression of epithelial to mesenchymal transition marker proteins including vimentin. Importantly, CAFs induce upregulation of the 7-transmembrane protein smoothened, the central signal transducer of hedgehog, suggesting that the hedgehog signaling pathway is active in CAF-mediated drug resistance. Indeed, downregulation of smoothened activity with the smoothened antagonist cyclopamine induces remodeling of the actin cytoskeleton independently of Gli-mediated transcriptional activity in PC9 cells. These findings indicate that crosstalk with CAFs plays a critical role in resistance of lung cancer to EGFR TKIs through induction of the epithelial to mesenchymal transition and may be an ideal therapeutic target in lung cancer.


This paper presents the findings of a study into the relationship between parents' jobs and the work values of apprentices. The findings were examined in the context of the positive relationship between work commitment and productivity of skilled workers and the need to understand influences on the work values of apprentices. The findings showed that the work values of apprentices were influenced by the kind of jobs each parent held. The importance of particular work values to apprentices differed significantly according to either their mother or father's job. ANOVA and Post Hoc analyses showed that the parents' role in their children's work values depended on the work value examined. The findings support literature specifically on intergenerational transmission of values, the occupational linkage hypothesis and the social learning theory on the influence of parents' occupation and children's values. They also show the importance for industry to focus on, and provide support to young apprentices in improving their commitment to work and help raise their productivity levels. The paper offers some suggestions on the kind of focus and support that can be offered.


Alveolar echinococcosis (AE) is a helminth zoonosis which is encountered only in the northern hemisphere. In central France, the Auvergne region represents the most western and southern extension of this helminthiasis. In 1999, a human case of AE was diagnosed in the southern part of the Cantal department, where AE was supposed absent, and an epidemiological survey was subsequently carried out. The transmission of the zoonosis in the sylvatic and peridomestic definitive hosts was studied, as well as that in the rodent and human intermediate hosts. Eleven red foxes (Vulpes vulpes) were shot, and 50 fox faecal deposits were collected. Twelve farm dogs had their faeces taken by rectal touch, and four were checked after arecoline purgation. Optical detection of Echinococcus multilocularis worms was achieved on fox intestines after scraping, and also on dog stools after arecoline therapy. Coproantigen ELISA assay was performed for the 11 scraping products, for the 50 fox faeces, and for the 12 dog faecal samples. No adult AE agent was observed by microscopy, and the ELISA assay yielded positive results in one of 11 fox intestines, one of 50 fox faeces, and 2 of 12 dog faecal samples. Twenty-five small mammals were trapped, of which 19 were Arvicola terrestris water voles. One rodent liver exhibited a hepatic lesion consistent with AE. An epidemiological questionnaire was completed in 85 human volunteers, who were also serologically tested for AE. Only one (the case's husband) exhibited a Western-blotting pattern indicative of a low-grade AE infection. The results of this preliminary study suggested a slow AE extension to the south of Cantal department from the northern focus.


This paper solves two puzzles about the interpretation of appositive constructions in English: (i) it explains why appositives robustly PROJECT even though they are interpreted in situ with respect to order-dependent phenomena such as discourse anaphora; (ii) it analyzes certain non-projective readings of appositives as instances of PERSPECTIVE SHIFT, a phenomenon that bears striking similarities with the phenomenon of shifted indexical pronouns. To solve the first puzzle, I assume that appositives are interpreted in surface position but adopt a less standard mechanism of operator scope according to which operators can bind lexical predicates or other operators. Since appositives form ForcePs and Force operators cannot be bound, it follows that appositives project even when placed in the syntactic scope of a higher operator. With respect to the second puzzle, I argue that shifted appositives are evaluated with respect to a secondary speech context introduced by a verb of saying or inferred from the larger discourse. Since the two mechanisms of projection and perspective shift are independent, they can be given a uniform analysis.


This paper presents a model of collaboration, based on a Participatory Action Research (PAR) approach, for the documentation and preservation of small languages. Thus, it addresses the intersection of two of the conference topics: community-based initiatives and collaborative teams. This model of collaboration was developed together with the Mayangna community of Nicaragua, with the logistic support of the local university, URACCAN, and its Linguistics Institute IPILC. The collaborative research group is currently formed by five local indigenous linguists and three external linguists (two of them graduate students). This paper is the result of the experiences, the thinking and the evaluation of the process undergone by this mixed group over the last 10 years. The emphasis of the group's work has been on the process itself: in shaping and refining it to be in accordance with the principles and goals of PAR. The Basic Principles on which this model is based lie on a re-balancing of the power structure between external and internal researchers and consist of: (i) the recognition of the existence of knowledge systems of equal value among external and internal linguists, (ii) an egalitarian relationship between external and internal researchers and (iii) the (self-)empowerment of the speaking community as a result of the process. For the purpose of this work, internal linguists are those who are also members of the speaking community and, in the best case scenario, also speakers of the language, while external linguists are those who are not members of the community. Assuming these principles, the General Goals that were established by the group are: (i) to create and train local technical indigenous linguistic teams, (ii) to create materials relevant for the community and (iii) to implement a participatory dynamic in the day-to-day work interaction of the members of the team. In order to achieve these goals, a set of Implementation Mechanisms is established, including three basic components: (i) a mechanism for joint decision making, to establish goals relevant to all participants; (ii) a mechanism for a continuous training program (to ensure mutual transfer of knowledge) and, most important, (iii) a mechanism of self-evaluation. Though this approach is a continuous work in progress, some intermediate milestones have been reached: a local linguistic team was formed and is operating, and basic documentation is currently underway (including linguistic materials --dictionaries, grammar, university textbooks, all of them written in the indigenous language-- and culturally relevant materials).


The evaluation of airport logistics competitiveness can identify the airports' advantages and disadvantages, and take certain measures to solve problems. In this paper, the airport logistics competitiveness evaluation index system has been built. The application of AHP method evaluates the logistics competitiveness of Hangzhou Xiaoshan International Airport (HIA) and the other four airport of Asia Pacific in comprehensive. The advantages and disadvantages of HIA in logistics have been obtained, which provide a scientific basis to improve its logistics competitiveness. The conclusion of the study is of some practical significance.


The question of impact looms over media policy scholarship. Despite engaging similar issues, media policy makers and communication scholars often diverge in defining the scope of the problems they address, with the former group largely guided by economic and legal analysis and influenced by partisan ideologies and political obligations. In the introductory essay for this Special Section, we highlight the value of communication scholars' contributions to policy debates, particularly given their broader analytical frame and critical focus. Against this backdrop, we situate the Consortium on Media Policy Studies (COMPASS) program, which is designed to immerse students of communication policy in the policy-making processes to inform their research. As the contributions to this Special Section illustrate, this nexus of communication scholarship and policy-making practice yields important insights and interventions, shedding light on the most pressing policy issues we face today.


Human mesenchymal stromal cells (MSCs) from different parts of the body (i.e. bone marrow, BM) have distinct cellular and molecular features including global gene expression profiles. Quantitative polymerase chain reaction is a reliable method used in the quantification of gene expression. Correct assessment of target gene expression mostly depends on the reference gene (RG) of choice. Herein, expression levels of RGs (n = 19) in adipo-/osteogenic-differentiated and control (uninduced) BM-MSCs from donors were measured using the RealTime ready Human Reference Gene Panel. Characterization of BM-MSCs was assessed using in vitro differentiation by histochemical staining and immunophenotyping of cells by flow cytometric analysis. BM-MSCs successfully differentiated into adipogenic and osteogenic lineages. When three groups were analyzed together, the NormFinder and GeNorm software programs identified PBGD as the most stable RG. GeNorm also reported G6PDH as the other stable gene. Due to their low expression, PBGD and G6PDH were not suitable RG candidates. RPLP0 had slightly lower stability but very high expression, rendering it as the best RG. When either adipogenic- or osteogenic-induced MSCs were analyzed with control BM-MSCs, the most stable RGs with high expression levels were revealed to be GAPDH and RPLP0. Even though ACTB had the highest expression, its stability was low.


Learning the similarity between structured data, especially the graphs, is one of the essential problems. Besides the approach like graph kernels, Gromov-Wasserstein (GW) distance recently draws a big attention due to its flexibility to capture both topological and feature characteristics, as well as handling the permutation invariance. However, structured data are widely distributed for different data mining and machine learning applications. With privacy concerns, accessing the decentralized data is limited to either individual clients or different silos.

To tackle these issues, we propose a privacy-preserving framework to analyze the GW discrepancy of node embedding learned locally from graph neural networks in a federated flavor, and then explicitly place local differential privacy (LDP) based on Multi-bit Encoder to protect sensitive information. Our experiments show that, with strong privacy protection guaranteed by ε-LDP algorithm, the proposed framework not only preserves privacy in graph learning, but also presents a noised structural metric under GW distance, resulting in comparable and even better performance in classification and clustering tasks. Moreover, we reason the rationale behind the LDP-based GW distance analytically and empirically.


Thales is planning to deliver systems with a Performance Based Logistic contract. Thales is responsible for the whole maintenance process against a fixed fee. The key performance indicator is the mission availability per ship over a certain time period. The mission availability is defined as the system uptime during the mission divided by the mission time (mission uptime + mission downtime). The downtime is measured by the supply availability. Within a performance based logistic contract, Thales will receive financial penalties when the mission availability drops below the agreed mission availability target. Thales receives a financial bonus when the system performed as agreed. It is of great importance for Thales to determine what the effects are of a performance based contract. Thales performed several studies to estimate the effects and costs of a performance based logistic contract. This research focuses on the transition from the key performance indicator 'supply availability' to the mission availability.
The objective of this research is to find an optimal spare parts allocation procedure for the antenna of the Smart-L ELR case. An optimal spare parts procedure involves minimizing the cost with as constraint a minimum mission availability target. Simultaneously it should take into account the mission's length, annual operational hours, repair lead-time, of the multi-indenture antenna. In addition Thales prefers an spare parts allocation procedure which is "robust". The solution of the optimized procedure are as less sensitive as possible for variations of the Mean Time Between Failure. In that case the solution may have slightly higher cost. With this objective the main research question is formulated:
What is the optimal spare parts allocation procedure of the antenna of the Smart-L ELR to ensure that the minimum mission availability constraint is satisfied, the cost are minimized, considering mission profiles, annual operational hours, and repair lead-time?
In this research there are four allocation procedures constructed, whereby the transfer point from Inventri to Simlox is different per procedure. The second procedure uses two types of ships, namely a mission ship and a short-mission ship. A mission ship goes on mission for several months and the short-mission ships will perform multiple short missions per year. The second procedure calculates the supply availability of the mission ships and the short-mission ships separately by Inventri. The mission ship allocation is combined with the ship spare parts of the short-mission ship allocations. Subsequently, Simlox is used to allocate the spare parts following a single-site METRIC allocation process, whereby the ships together are considered as single-site. Procedure 3 calculates the spare parts allocation to a supply availability level of 99.99% with Inventri. Afterwards checks the allocation list when the short-mission ship is allocated too. The spare parts allocation list, until the short-mission ship is allocated, is implemented in Simlox. Subsequently, Simlox is used to allocate the spare parts following a single-site METRIC allocation process, whereby the ships together are considered as single-site.
The case study consists of a 3-echelon, multi-indenture supply network with three ships, one shore stock location and one original equipment manufacturer (Thales).
From this case study, we can conclude:
The third procedure generates higher mission availability solutions which are less sensitive to MTBF variations, but costs slightly more
An experiment is conducted whereby it seems that the mission availability in procedure 3 is less sensitive to MTBF variations due to higher average mission availability solutions. The slightly more expensive procedure copes better to MTBF variations. Thales prefers a procedure which copes better to
MTBF variations, regardless it has slightly higher costs. The third procedure can cope for this case at least to 12.5% lower Smart-L antenna MTBF values, but costs maximal 11% more.
Procedure 2 generates overall the most cost-effective solutions
Procedure 2 generates overall the most cost-effective solutions. Compared to procedure 3 this is a more labor-intensive procedure (more iterations), but generates cheaper solutions.
The probability of backorders reduction is made plausible linearly proportional to the mission availability addition.
It is made plausible that the delta probability of backorders (PBO) is linearly proportional to the delta mission availability. This is made plausible for a 3-echelon structure whereby in all the stock locations the delta EBO is made plausible to be linearly proportional to the delta mission availability. This results in that the choices of the VARI-METRIC model can be used to allocate the spare parts.
The reduction of the repair lead-time can reduce the initial spare parts cost in this case with 39.76%, but it can only be realized by stocking component spare parts.
The largest total initial spare parts cost is achievable by reducing the repair lead-time. The reduction of the repair lead-time is only allowable when Thales stocks components as spare parts. The component spare parts cost is much lower than the Line Replaceable Unit (LRU) spare parts. The maximal initial spare parts cost reduction is for a steady state model in this Smart-L case 39.76%.
The reduction of the shipment cycle time reduces the initial spare parts costs, in this case 28.13%.
The one month shipment cycle time and two months shipment cycle time is studied and how it influences the initial spare parts costs. The total initial spare parts cost is higher for the shipment time of two months than the total initial spare parts cost of one month. The initial spare parts costs reduction is in this Smart-L case 28.13%.
The following recommendation can be presented based on this case study:
Use the third procedure to allocate the spare parts for requested minimum mission availability target, because it generates in general higher mission availability solutions which are less sensitive to MTBF variations
This procedure, which generates a solution with slightly higher costs, can cope better with the MTBF variations due to higher average mission availability solutions. Therefore the recommendation is to use the third procedure for allocating the spare parts to stock locations.
Reduce the repair lead-time, because it reduces the initial spare parts costs
In the systems of Thales there are a lot of printed circuit boards. These printed circuit boards are designed to be an LRU. In a PBL contract environment the inventory costs are at the expense of Thales. The recommendation is that costs can be saved by reducing the repair lead-time in a PBL contract environment. Reducing the repair lead-time can only be realized by stocking components as spare parts.
Reduce the shipment time between customer's site and the ships from two months to one month
The total initial spare parts cost is higher for the shipment time of two months then the total initial spare parts cost of one month. Therefore, the recommendation is to agree in terms of the PBL contract a one month shipment time. The initial spare parts costs reduction is in this Smart-L case 28.13%.


Both CD4+ and CD8+ T cells contribute to immunity to tuberculosis, and both can produce the essential effector cytokine IFN-γ. However, the precise role and relative contribution of each cell type to in vivo IFN-γ production are incompletely understood. To identify and quantitate the cells that produce IFN-γ at the site of Mycobacterium tuberculosis infection in mice, we used direct intracellular cytokine staining ex vivo without restimulation. We found that CD4+ and CD8+ cells were predominantly responsible for production of this cytokine in vivo, and we observed a remarkable linear correlation between the fraction of CD4+ cells and the fraction of CD8+ cells producing IFN-γ in the lungs. In the absence of CD4+ cells, a reduced fraction of CD8+ cells was actively producing IFN-γ in vivo, suggesting that CD4+ effector cells are continually required for optimal IFN-γ production by CD8+ effector cells. Accordingly, when infected mice were treated i.v. with an MHC-II–restricted M. tuberculosis epitope peptide to stimulate CD4+ cells in vivo, we observed rapid activation of both CD4+ and CD8+ cells in the lungs. Indirect activation of CD8+ cells was dependent on the presence of CD4+ cells but independent of IFN-γ responsiveness of the CD8+ cells. These data provide evidence that CD4+ cell deficiency impairs IFN-γ production by CD8+ effector cells and that ongoing cross-talk between distinct effector T cell types in the lungs may contribute to a protective immune response against M. tuberculosis. Conversely, defects in these interactions may contribute to susceptibility to tuberculosis and other infections.


In this paper we explore the potential of cross-fertilization between research on welfare state reforms and on efforts to green the state in response to ecological challenges. In order to gain a deeper understanding of the conditions for an ecological state to emerge we relate welfare state studies to green political theory, that provide different conceptions of the ecological state and ways to green the state, and to comparativist environmental politics that trace patterns of policy change and institutionalization for greening the state in practice. Recently some scholars have made analogies between the evolution of the ecological state and the genesis of once the welfare state. However, while providing insights on such similarities and on the kind of challenges environmental change poses for the welfare state, our concern is rather what challenges contemporary welfare state transformations pose for the efforts to green the state. How are we to understand calls for the revitalization of the state in light of key contradictions in welfare state developments such as the fiscal crisis of welfare states, liberalization of welfare policies and increasing inequalities? In this sense, the marketization of environmental policy and individualization of ecological responsibilities could be understood in analogy with the retrenchment and recommodification of welfare policy. Such welfare state developments has critical implications for the efforts to strengthen state competences and capacities for governing societies towards ecologically sustainable and socially just ends, e.g. in terms of legitimizing and organizing both ecological and social aspirations. (Less)


As electricity markets are liberalized, consumers become exposed to more volatile electricity prices and may decide to modify the profile of their demand to reduce their electricity costs. This paper analyzes the effect that the market structure can have on the elasticity of the demand for electricity. It then describes how the consumers' behavior can be modeled using a matrix of self- and cross-elasticities. It is shown how these elasticities can be taken into consideration when scheduling generation and setting the price of electricity in a pool based electricity market. These concepts are illustrated using a 26-generator system.


We do not say that a man who takes no interest in politics minds his own business. We say he has no business here at all. Pericles In reviewing the literary accomplishments of some of my distinguished predecessors I find that presidential addresses before this association give a historical perspective of neurology. On occasion the confines of specialization have been departed. Then not only is the current state of affairs in neurology and other health fields scrutinized, but also social orientations, that bear so heavily on the ills of our clientele. In this the third quarter of the twentieth century, the profession is being subjected to all sorts and conditions of pressure. I suppose that among these bombardments, stimulating or irritating, depending upon one's point of view, none engenders more heat than those defined as political. Politicians, ever given to regulating others, would have us conduct our affairs according to


This article explains how a charged body can retain its integrity despite electrostatic repulsion within itself. The study requires derivation of the field equations governing the velocity of any arbitrary element within the system. These relations are obtained from two Lagrangian principles based on obvious and least disruptive modifications of known concepts in classical mechanics. The two Lagrangians lead to a relativistic energy-momentum equation describing the motion and Maxwell's equations quantifying the electromagnetic fields, respectively. The energy-momentum relation shows that rigid body motions creating stationary fields in a rotating frame is a viable solution for the velocity inside the continuum. It also yields a combined potential which remains constant throughout the rotating particle. This constancy coupled with Maxwell's equations and boundary conditions for proper interfacial continuity provides the charge distribution and geometric shape required for continued coherence of the domain. The paper presents specific simulations for slender annuli steadily rotating about the axis of symmetry where the charge density and the axial width are plotted as radial functions. Curiously, when the analysis is extended to systems with different axes of rotation and symmetry, the proportionalities between energy and frequency as well as momentum and wave-number can be established. Such results are very similar to Planck's and de Broglie's laws, even though derived from classical principles. Thus, the presented theory might have deeper implications like, for example, in mathematical computation of fine structure constant.


Normal and Eck fistula dogs react in a similar manner to the intravenous injection of hemoglobin obtained from laked red cells of the same animal. Hemoglobin appears in the urine after a few minutes and bile pigments in one to one and one half hours. In this simple type of hematogenous jaundice the reaction is in no way influenced by shutting out the portal blood from the liver and cutting down its blood supply to about 25 per cent. of normal. In a second type of hematogenous jaundice produced by chloroform anesthesia, which produces central liver necrosis, there is no essential difference between the normal and Eck fistula dog. The Eck fistula dog, as a rule, is more resistant to this poison, but, given a definite liver necrosis, the jaundice developing will reach its maximum on the second day as in the normal animal. This jaundice must be explained in part by capillary biliary obstruction, but in part by a hemolysin formed in the injured liver cells (Joannovics and Pick). Simple obstruction of the common duct when combined with an Eck fistula gives rise to a definite low grade icterus with bile pigment constantly present in the urine. Under these conditions after doubly ligating and cutting the common duct with separation of the cut ends, the lumen of the duct may be established and bile may enter the intestine by means of a fistulous tract between the cut ends of the bile duct. The formation of bile and bile pigments is much less in an Eck fistula dog than in a normal animal and consequently the icterus is much less intense. This is probably due to a lessened activity of the liver cells because of decreased blood supply. This observation does not harmonize with the current view that bile pigments are formed solely from hemoglobin, as there is no evidence of more hemolysis in a normal than in an Eck fistula dog. This suggests that the bile pigment may be formed in part, at least, from other substances than hemoglobin, and, further, that bile pigment formation normally may depend in part upon the functional activity of the liver cell rather than upon the amount of hemoglobin supplied to it.


The acetabular labrum plays a vital role in normal biomechanics of the hip joint. Both nociceptive and proprioceptive fibers are present in the labrum and their presence determines the rationale behind surgical labral treatments. In patients with femoroacetabular impingement (FAI) syndrome, a variety of labral injuries are observed. These may be the source of significant motion- and position-related hip and/or groin pain. However, there is a high prevalence of asymptomatic labral tear in the general and athletic population. Non-surgical treatment for symptomatic individuals includes education, activity modification, physical therapy, non-opioid oral medications, and injections. In the event of non-surgical treatment failure in non-arthritic and non-dysplastic individuals, surgical treatment includes labral repair and correction of cam, pincer, and subspine morphologies, and capsular management. Labral reconstruction is usually a revision procedure. However, in select primary cases (ossified labrum, global overcoverage pincer, irreparable tear), a reconstruction (or debridement) may be performed.


Background Direct measures of HIV incidence are needed to assess the population-level impact of prevention programs but are scarcely available in the subnational epidemic hotspots of sub-Saharan Africa. We created a sentinel HIV incidence cohort within a community-based program that provided home-based HIV testing to all residents of Namibia's Zambezi region, where approximately 24% of the adult population was estimated to be living with HIV. Objective The aim of this study was to estimate HIV incidence, detect correlates of HIV acquisition, and assess the feasibility of the sentinel, community-based approach to HIV incidence surveillance in a subnational epidemic hotspot. Methods Following the program's initial home-based testing (December 2014-July 2015), we purposefully selected 10 clusters of 60 to 70 households each and invited residents who were HIV negative and aged ≥15 years to participate in the cohort. Consenting participants completed behavioral interviews and a second HIV test approximately 1 year later (March-September 2016). We used Poisson models to calculate HIV incidence rates between baseline and follow-up and multivariable Cox proportional hazard models to assess the correlates of seroconversion. Results Among 1742 HIV-negative participants, 1624 (93.23%) completed follow-up. We observed 26 seroconversions in 1954 person-years (PY) of follow-up, equating to an overall incidence rate of 1.33 per 100 PY (95% CI 0.91-1.95). Among women, the incidence was 1.55 per 100 PY (95% CI 1.12-2.17) and significantly higher among those aged 15 to 24 years and residing in rural areas (adjusted hazard ratio [aHR] 4.26, 95% CI 1.39-13.13; P=.01), residing in the Ngweze suburb of Katima Mulilo city (aHR 2.34, 95% CI 1.25-4.40; P=.01), who had no prior HIV testing in the year before cohort enrollment (aHR 3.38, 95% CI 1.04-10.95; P=.05), and who had engaged in transactional sex (aHR 17.64, 95% CI 2.88-108.14; P=.02). Among men, HIV incidence was 1.05 per 100 PY (95% CI 0.54-2.31) and significantly higher among those aged 40 to 44 years (aHR 13.04, 95% CI 5.98-28.41; P<.001) and had sought HIV testing outside the study between baseline and follow-up (aHR 8.28, 95% CI 1.39-49.38; P=.02). No seroconversions occurred among persons with HIV-positive partners on antiretroviral treatment. Conclusions Nearly three decades into Namibia's generalized HIV epidemic, these are the first estimates of HIV incidence for its highest prevalence region. By creating a sentinel incidence cohort from the infrastructure of an existing community-based testing program, we were able to characterize current transmission patterns, corroborate known risk factors for HIV acquisition, and provide insight into the efficacy of prevention interventions in a subnational epidemic hotspot. This study demonstrates an efficient and scalable framework for longitudinal HIV incidence surveillance that can be implemented in diverse sentinel sites and populations.


In this paper, we describe theoretical studies, using gas-phase quantum chemical calculations, on carbocationic rearrangement pathways leading to the sesquiterpenes sativene, cyclosativene, alpha-ylangene, and beta-ylangene. For all four sesquiterpene natural products, viable pathways are presented, and these are compared both to mechanistic proposals found in the literature, and in certain cases to alternative stereochemical and rearrangement possibilities, thus providing a basis for comparison to experimental results. We find that these four sesquiterpenes likely arise from a common bicyclic intermediate and, furthermore, that the computed pathways are mostly in agreement with previous mechanistic proposals, although the few differences that we have uncovered are significant. Additionally, the potential energy profiles of the pathways are found to be very flat, supporting the notion that following the initial ionization of farnesyl diphosphate, minimal enzymatic intervention may be required for the generation of such sesquiterpenes.


With a recent decision, the European Commission has cleared, subject to a number of commitments given by the parties, the proposed acquisition by Generali, the Italian company leader in the insurance sector, of INA, one its largest competitors, by means of a public offer. According to the commitments attached to the decision Generali will divest its controlling stakes in three subsidiaries active in the life insurance sector, and its minority shareholding in the competitor Fondiaria, while INA will divest its controlling stakes both in the bank Banco di Napoli and in the insurance company BNL Vita. Moreover, Generali will eliminate or reduce the interlocking directorships concerning the Board of directors and Executive Committee of INA and those concerning its own Board and Executive Committee. The commitments concerning the reduction of interlocking directorates will prevent such personal relationships from affecting the competitive behaviour of the market players. Furthermore, as regards Fondiaria, the commitment that Generali will dispose of its stake in that company will remove a link which again could have led to the co-ordination of the commercial behaviour of the two companies. The European decision and the committments attached to are examined in the light of the particular ownership structure of the Italian insurance and financial system, characterized by a thick web of reciprocal and circular holdings and the extensive recourse to interlocking directorates between competing companies. It is suggested that this structure may lead to undesirable distortions of competition, exacerbated by some specific characteristics of the financial markets and prudential regulation. Morever, the enforcement of prudential regulation by the Italian surveillance authorities, even if partly justified from a stability point of view, seems to strengthen the present ownership structure, by disfavoring hostile takeovers, and by rendering more difficult the entry into the markets of foreign companies through mergers. In that situation, the imposition of remedies in the appraisal process of mergers by antitrust authorities is an important tool but it may not suffice to restore conditions of effective competition in the markets. The paper suggests that in order to overcome the restrictions of competition led by the "circular" ownership structure prevailing in the Italian financial system, alternative tools should be used, such as the rules against anticompetitive agreements, and considers the possibility to introduce a regulation dealing specifically with interlocking directorates.


Objective: This study aimed to compare the bactericidal effect of Nd: YAG laser and sodium hypochlorite solution. Background: It is very important to obtain the best sterilization and antibacterial effect during treatment of the infected root canals. Materials and methods: Bacterial samples were taken from infected root canals immediately after the tooth extraction. The samples were divided into 3 groups, each group contained 30 individuals. In the first group, sodium hypochlorite was used alone as a bactericidal agent. In the second group, Nd: YAG laser was used as a bactericidal agent. In the third group, both of them were used. Bacterial swabs were taken from these samples before and after treatment by each bactericidal agent, these swabs were streaked on blood agar and incubated, and the number of the colony forming units was recorded. The diameter of the non-growth zone was measured after exposure to each bactericidal agent. Results: The results showed an excellent bactericidal effect for the sodium hypochlorite group. The number of colony forming units was reduced to about 89% from the original number before the treatment. While the Nd: YAG laser exhibited a weak bactericidal effect with about 25% of the bacterial cells eradicated. The best antibacterial activity obtained was when both sodium hypochlorite and Nd: YAG laser were used together, with a percentage of reduction of about 96%. Conclusion: The sodium hypochlorite has a very good bactericidal action if compared to Nd: YAG laser. The Nd: YAG laser was merely effective as a bactericidal agent. The best bactericidal effect was observed when both sodium hypochlorite and Nd: YAG laser were used together. Nd: YAG could be used as a co-adjunctive agent to agitate the sodium hypochlorite solution and to increase its activity.


In this prospective study, we evaluated contamination of surgical fields in open heart operations by salvaged blood culture used in autologous transfusions device (Cell Saver 5, Heamonetics Corp., Braintree, MA, USA). And also, we prospectively investigated an efficacy of pre- and intra-operative prophylactic antibiotics administrations (cefazolin). Thirty patients undergone open heart surgeries with median sternotomy enrolled in this study. The patients were divided into two groups, group A (n = 15); without prophylactic antibiotics administration, group B (n = 15); with pre- and intra-operative prophylactic antibiotics administrations. Blood samples were drawn through the right atrium after the discontinuation of CPB and from salvaged blood bags. Bacterial growth was detected in 80.0% of salvaged blood samples in group A, 86.7% in group B (p = 0.62). Whereas no bacterial growth detection in blood samples though the right atrium. Quantitative estimates of contaminations showed 1.06 +/- 1.41, 0.90 +/- 1.24 cfu/ml, respectively (p = 0.22). Although bacterial growth rate were not statistically significant difference between groups, detective rate of Staphylococci was remarkably decreased (p = 0.005) in group B. Pre- and intra-operative prophylactic antibiotics administrations were effective for Staphylococci, but not whole microorganisms. In conclusion, salvaged blood used in autologous transfusions was highly contaminated and it suggests that surgical fields were not clear. Prophylactic antibiotics administrations were effective especially for Staphylococci.


This study was designed to determine the maximum replacing levels of Fish Meal (FM) by a Plant Protein Mixture (PPM) in eight diets for Nile tilapia. The PPM consisted of cottonseed, sunflower, canola, seasme and linseed meals. FM in the basal diet was replaced by PPM in the diets at replacing levels of 15, 30, 45, 60, 75, 90 and 100%. A total number of 480 Nile tilapia were randomly distributed into eight treatments, each in three replicates. After 12 weeks of feeding, replacement of 15, 30 or 45% of FM by PPM did not significantly affected Feed Intake (FI), Feed Conversion Ratio (FCR), Protein Efficiency Ratio (PER) and the Apparent Digestibilities Coefficient (ADC) of Dry Matter (DM), Crude Protein (CP) and Ehter Extract (EE), while the highest replacing levels (60, 75, 90 or 100%) significantly (P<0.05) reduced these parametesr. Growth parameters were relatively parallel to those of FI, FCR and PER whereas, replacement up to 45% exhibited Body Weight (BW), Body Length (BL), Weight Gain (WG) and Specific Growth Rate (SGR) not differing significantly (P<0.001) from the fish fed control diet. Compared to control, increasing PPM in the diets significantly reduced hemoglobin, hematocrite and the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The incorporation of PPM in diets did not significantly affect whole-body Dry Matter (DM) and Crude Protein (CP). From economic view, replacement of FM by PPM up to 45% in tilapia diets reduced feed costs/kg diet and feed costs/kg weight gain by 11.40 and 6.74%, respectively.


A higher-order potential flow method is adapted for the aerodynamic performance prediction of small rotors used in multirotor unmanned aerial vehicles. The method uses elements of distributed vorticity which results in numerical robustness with both a prescribed and relaxed wake representation. The radial loading and wake shapes of a rotor in hover were compared to experiment to show strong agreement for three disk loadings. The advancing flight performance prediction of a single rotor was compared to a single rotor was compared to a blade element momentum theory based approach and to experiment. Comparison showed good thrust and power agreement with experiment across a range of advance ratios and angles of attack. Prediction in descending flights showed improvements in comparison to the blade element momentum theory approach. The model was extended to a quadrotorm configuration showing the differences associated to vehicle orientation and rotor rotational direction.


Suppression of chaotic instability arising in a Nd:YVO(4) microchip laser subject to frequency-shifted optical feedback is accomplished by injection of one of the periodic orbits into the bifurcation region of another chaotic system driven by pump modulation. Various periodic patterns, which do not exist in the original chaotic attractor, can be extracted from the chaotic oscillation by use of this nonfeedback chaos-control technique.


Background: Different instrumentation systems and techniques are used in the instrumentation of the root canal system which can result in debris formation that may be extruded beyond the apical foramen and cause post-operative pain. Aim of the study: Aim of the current study was to compare the amount of apically extruded debris and irrigants during instrumentation using 2 reciprocating single file systems (WaveOne Gold, Reciproc blue) and 2 continuous rotation file systems (ProTaper Gold, 2Shape) and comparing them to the control group (ProTaper Universal). Materials and Methods: Total 50 palatal roots of freshly extracted human maxillary first molars were collected for this study. Teeth were decoronated to a unified length of 15 mm, and then pushed through a pre-perforated rubber cap of pre-weighed glass vial then the root-cap complex was fitted on a glass vial and rubber dam ligated with dental floss was used to cover the glass vial for preventing the coronally extruded debris and irrigants from contaminating the external surface, gauge 25 needle was inserted parallel to the root surface through the rubber dam and cup. Samples were then randomly divided into 5 groups. Results: Data obtained were statistically analyzed using One Way ANOVA and LSD tests. The result showed that all groups resulted in apical extrusion of debris and irrigants, as it showed that the 2Shape Group B, Wave One Gold Group C and Reciproc blue Group D are statistically comparable, while ProTaper Gold Group A and ProTaper Universal Groups E showed statistically significant difference (p<0.05). Conclusions: All of the systems resulted in apical extrusion. There was no influence of kinematic movements on apical extrusion. The 2shape file system produced the least amount of apical extrusion while the ProTaper Universal showed the greatest amount.


What should you do when you see a fellow student behaving inappropriately? After a group of students wrote to the BMJ about their experience during an elective (doi:10.1136/bmj.a2874), we sought the opinions of an ethicist (doi:10.1136/bmj.a2882), a dean (doi:10.1136/bmj.a2884), a GMC representative, and a lecturer from an African university (doi:10.1136/bmj.a2875)


This study investigates contractor selection by Malaysian housing developers. In order to maintain competitive advantage, businesses such as housing developers need to strive to give their customers better value for money. Selecting the right contractor enhances project delivery outcomes and could help this cause. With this in mind, this study is concerned with the contractor (supplier) evaluation and selection by housing developers in procuring contractor services (Watt et al., 2010a) and the effects of relational norms -1) trust norms (Dwyer et al., 1987; Morgan and Hunt, 1994; Doney and Cannon, 1997) and 2) cooperative norms (Zhong et al., 2014; Cai and Yang, 2008; Eriksson, 2007b) and 3) prequalification (Aje, 2012; Hatush and Skitmore, 1997; Jennings and Holt, 1998) on contractor selection in industrial exchange relationship.
Three research questions were considered:
Research question 1 how do the relationships between developers and contractors affect the selection procedure?
Research question 2 how do the contractor's tender price, financial standing and expertise affect the selection procedure?
Research question 3 do housing developers in Malaysia carry out contractor prequalification as part of their contractor selection procedure?
With support from literature, seven hypotheses are advanced to deal with these issues;
H1: Norms are the second order construct with two sub-dimensions trust norms (H1a) and cooperative norms (H1b)
H2: Norms have a positive impact on contractor selection
H3: Price has a positive impact on contractor selection
H4: Past experience has a positive impact on expertise
H5: Finance has a positive impact on expertise
H6: Contractor expertise has a positive impact on prequalification
H7: Prequalification has a positive impact on contractor selection
Data was collected from the Malaysia Real Estate and Housing Development Association (REHDA). A postal survey of 545 housing development companies' entries in the REHDA registry 2009 / 2010 produced 155 completed questionnaires comprising responses from 64 small size firms; 38 medium size firms and 53 large size firms. The overall response rate was 28.4%. Biases were examined for but none were found.
The empirical investigation involved the use of Partial Least Square - Structural Equation Modelling (PLS-SEM); the advanced quantitative data analysis techniques. All results were cross validated by the expert group discussion method.
In term of contributions to theory, the aggregate model shows that price and relationship have small effects on contractor selection whereas prequalification has medium effect on contractor selection. Selection criteria such as contractors' qualification on financial standing, past experience and company expertise have significant effect on selection. Therefore, the higher the contractor qualification in those criteria, the more likely they are to be selected for the job.
In terms of contribution to construction management practice, this study offers an understanding of how housing developers in Malaysia select their main contractors. According to the findings of this research, developers especially the larger firms rely less on relationship criterion but prefer to use prequalification in their contractor selection. This study demonstrate that the contractor selection is based on multi-criteria - beyond those traditionally used such as time, quality and cost - also known as "iron triangle". Using multi criteria prequalification methods helps developers to source for contractors with the necessary capabilities and expertise to match the complexity of projects. This study also highlights the role of developer and contractor relationships as the non–financial criteria (such as cooperative norms and trust norms in contractor selection) especially among small size developers firms.


Barrier deposits preserved on continental shelf seabeds provide a record of the paleocoastal environment from the last glacial maximum through the Holocene. The formation of these offshore deposits is often attributed to intermittent periods of rapidly rising sea levels, especially glacial meltwater pulses, which are expected to lead to partial or complete drowning—overstepping—of migrating barrier islands. However, recent cross-shore modeling and field evidence suggests that even for constant sea-level rise and shelf slope, the internal dynamics of migrating barriers could plausibly drive periodic retreat accompanied by autogenic partial overstepping and deposition of barrier sediment. We hypothesize that the interaction of periodic retreat with changes in external (allogenic) forcing from sea-level rise may create novel retreat responses and corresponding relict barrier deposits. Specifically, we posit that autogenic deposits can be amplified by an increased rate of sea-level rise, while in other cases internal dynamics can disrupt or mask the production of allogenic deposits. Here, we model barriers through a range of autogenic-allogenic interactions, exploring how barriers with different inherent autogenic periods respond to discrete, centennial-scale sea-level-rise pulses of variable magnitude and timing within the autogenic transgressive barrier cycle. Our results demonstrate a diversity of depositional signals, where production of relict sands is amplified or suppressed depending on both the barrier's internal dynamic state and the pulse magnitude. We also show that millennial-scale autogenic periodicity renders barriers vulnerable to complete drowning for relatively low pulse rates of rise (< 15 mm/yr).


This paper is presenting a betterment steganographic method for covert channel communication. Two distinct methods are combined to achieve possibly high data hiding capability with high visual quality. The proposed method shifts the last n nonzero AC coefficients from S JPEG block, and changes the magnitude values of the first n nonzero AC coefficients from T JPEG blocks. S and T blocks are determined by the number of nonzero JPEG coefficients in the block. Zero run-length modification method improves the robustness against statistical attack based on magnitude histogram. Magnitude modification method improves the visual quality. This combination complements each other.


CONTEXT
Physicians depend on the medical literature to keep current with clinical information. Little is known about residents' ability to understand statistical methods or how to appropriately interpret research outcomes.

OBJECTIVE
To evaluate residents' understanding of biostatistics and interpretation of research results.

DESIGN, SETTING, AND PARTICIPANTS
Multiprogram cross-sectional survey of internal medicine residents.

MAIN OUTCOME MEASURE
Percentage of questions correct on a biostatistics/study design multiple-choice knowledge test.

RESULTS
The survey was completed by 277 of 367 residents (75.5%) in 11 residency programs. The overall mean percentage correct on statistical knowledge and interpretation of results was 41.4% (95% confidence interval [CI], 39.7%-43.3%) vs 71.5% (95% CI, 57.5%-85.5%) for fellows and general medicine faculty with research training (P < .001). Higher scores in residents were associated with additional advanced degrees (50.0% [95% CI, 44.5%-55.5%] vs 40.1% [95% CI, 38.3%-42.0%]; P < .001); prior biostatistics training (45.2% [95% CI, 42.7%-47.8%] vs 37.9% [95% CI, 35.4%-40.3%]; P = .001); enrollment in a university-based training program (43.0% [95% CI, 41.0%-45.1%] vs 36.3% [95% CI, 32.6%-40.0%]; P = .002); and male sex (44.0% [95% CI, 41.4%-46.7%] vs 38.8% [95% CI, 36.4%-41.1%]; P = .004). On individual knowledge questions, 81.6% correctly interpreted a relative risk. Residents were less likely to know how to interpret an adjusted odds ratio from a multivariate regression analysis (37.4%) or the results of a Kaplan-Meier analysis (10.5%). Seventy-five percent indicated they did not understand all of the statistics they encountered in journal articles, but 95% felt it was important to understand these concepts to be an intelligent reader of the literature.

CONCLUSIONS
Most residents in this study lacked the knowledge in biostatistics needed to interpret many of the results in published clinical research. Residency programs should include more effective biostatistics training in their curricula to successfully prepare residents for this important lifelong learning skill.


The problems of staffing an ICU in a District General Hospital at junior level are discussed. The needs of the Unit, the junior staff and the Anaesthetic Department and possible ways of reconciling these are outlined. A system of providing cover using pairs of junior anaesthetists is described in detail. This has been successfully in operation for 18 months and its merits are discussed.


This paper relates to the analysis of characteristics of trips and users who drive their car to the stations of the high capacity passenger transport system, in which they embark and continue the trip to their workplace. The authors study this type of trip related to the accessibility of downtown and with the quality of car parking facilities next to the stations and at the workplace. The transport data within the Metropolitan Region of Sao Paulo presents information about these trips, known as Park and Ride, on the subway lines. Parking at stations, trip pattern characteristics and users' socioeconomic status were studied. The user behavior was analyzed in order to model choice between going directly by car to the workplace or going by car to the station and taking the subway to the workplace. A discrete choice model was proposed based on the random utility theory. The variables considered are the difference in total travel times, the difference in parking prices and the quality of parking next to the station. A binomial logit model was considered and a stated preference survey was conceived. A case study was conducted and users of a car parking lot next to the subway at Tiete Station were interviewed. The results of the interviews were used to calibrate and compare the discrete choice models tested. It was verified that the difference in total travel times between the alternatives is more important than the difference in parking prices in transport mode choice decision making. It was also verified that quality is significant to users, and it is seen as higher when parking is inside the metro station building. This is probably due to time savings and both comfort and safety.


Bacterial abundance, biomass, volume and morphological diversity were studied in sediments collected in the eastern Adriatic Sea (Kastela Bay) in order to investigate their relationship with changes in environmental parameters. To asses the changes in the investigated parameters on a temporal scale and between sediment layers, the sediment samples were collected monthly in 2002 with a piston corer from the sediment surface to a depth of 10 cm. The concentrations of organic matter (OM), chloroplastic pigment equivalents (CPE), chlorophyll a (chl a ) and phaeopigments (PHAEO) were used as indicators of substrate concentrations in sediments. Sediment depth was a significant factor influencing the distribution of bacterial abundance, biomass and volume. Granulometric properties of the sediment had no effect on the distribution of bacteria. Bacterial abundance, biomass and volume were strongly related to the indicators of substrate concentrations on both scales. The accumulation of labile OM in deeper layers also had a profound effect on the size and structure of bacteria. High amounts of OM and the low proportion of labile organic fraction (CPE; chl a and PHAEO) indicate that this environment acts as a sink for accumulation of detrital material.


The disparity between public sensibilities and empirical data has become so extreme that certain topics can no longer be investigated without bringing down cries of "racism". Nevertheless, blacks commit violent crimes at four to eight times the white rate. Hispanics commit violent crimes at about three times the white rate, and Asians at one half to three quarters the white rate. Blacks are as much more criminally violent than whites, as men are more violent than women. Therefore, just as police stop and question men more often than women, they should stop blacks more often than whites. Of the approximately 1,700,000 interracial crimes of violence involving blacks and whites, 90 percent are committed by blacks against whites. Blacks are 50 times more likely than whites to commit individual acts of interracial violence. They are up to 250 times more likely than whites to engage in multiple-offender or group interracial violence. There is more black-on-white than black-on-black violent crime. Fifty-six percent of violent crimes committed by blacks have white victims. Only two to three percent of violent crimes committed by whites have black victims. Violent crime and interracial violence are important, agonizing concerns in this country, and we cannot begin to formulate solutions until we understand the problems.


ABSTRACT Wooden crates are a recurring subject in the visual archive of settler colonialism in Canada's Arctic, appearing on the shores of eastern Baffin Island throughout the first half of the twentieth century. Reading some of the hundreds of photographs that appear in the holdings of Library and Archives Canada in Ottawa, this essay charts the symbolic and political work that crates performed in the settler colonial imaginary. It draws on David L. Eng's call to examine the 'colonial object relations' that have split Indigenous subjects into 'good and bad objects' in the liberal imaginary to propose that wooden crates are symptomatic of settler colonialism's unconscious drive to make and unmake Inuit subjects into citizens in response to the demands of national and transnational political events. Tracing the intersection of crates, photography and ballot boxes in the archive, the essay examines the settler colonial state's attempts at imposing and consolidating power, but also points to the practices of continuity and resistance enacted by Inuit subjects.


The study finds strong correlations between natural products business performance and the impeding factors. The impediments include access to finance and markets, lack of herbal market information especially relating to external markets. Additionally, there is lack of processing capacity, while at the same time most if not all the natural products business operators lack technical training relating to product handling. However, there is big potential for success, the top ten traded natural products, may be exploited initially, both domestically and for export market, given range of perceived use. The constraints identified require concerted efforts from all stakeholders to recognize the importance of this sub-sector in providing opportunities to successful development.


Most vaccines, including those against influenza, were developed by focusing solely on humoral response for protection. However, vaccination activates different adaptive compartments that might play a role in protection. We took advantage of the pandemic 2009 A(H1N1) influenza vaccination to conduct a longitudinal integrative multiparametric analysis of seven immune parameters in vaccinated subjects. A global analysis underlined the predominance of induction of humoral and CD4 T cell responses, whereas pandemic 2009 A(H1N1)–specific CD8 responses did not improve after vaccination. A principal component analysis and hierarchical clustering of individuals showed a differential upregulation of influenza vaccine–specific immunity including hemagglutination inhibition titers, IgA+ and IgG+ Ab-secreting cells, effector CD4 or CD8 T cell frequencies at day 21 among individuals, suggesting a fine-tuning of the immune parameters after vaccination. This is related to individual factors including the magnitude and quality of influenza-specific immune responses before vaccination. We propose a graphical delineation of immune determinants that would be essential for a better understanding of vaccine-induced immunity in vaccination strategies.


Formation ∞ight is the primary movement technique for teams of helicopters. However, the potential for accidents is greatly increased when helicopter teams are required to ∞y in tight formations and under harsh conditions. The starting point for safe autonomous ∞ight formations is to design a distributed control law attenuating external disturbances coming into a formation, so that each vehicle can safely maintain su‐cient space between it and all other vehicles. In order to avoid the conservative nature inherent in distributed MPC algorithms, we begin by designing a stable MPC for individual vehicles, and then introducing carefully designed inter-agent coupling terms in each performance index. The proposed algorithm works in a decentralized manner, and is applied to the problem of helicopter formations comprised of heterogenous vehicles. The disturbance attenuation property of the proposed MPC controller is validated throughout a series of computer simulations.


Abstract The beet armyworm, Spodoptera exigua Hübner (Lepidoptera: Noctuidae) is a serious agricultural pest worldwide. However, population sources of S. exigua in outbreak regions are still vague due to the lack of understanding the distribution of overwintering regions, especially in China. In the present study, the potential overwintering regions of S. exigua in China are projected using the method of Compare Location in the CLIMEX model in order to understand the population sources in outbreak regions and establish an accurate forecasting system. The results showed the southern and northern overwintering boundaries near the Tropic of Cancer (about 23.5 °N) and the Yangtze River valley (about 30 °N), respectively. Meanwhile, the projection was supported by the data of fieldwork in 14 countries/cities during winter from 2008–2010. In conclusion, results of this study indicated that the overwintering regions of S. exigua were accurately projected by the CLIMEX model.


With the increasing complexity of systems found in practical applications, the problem of controller design is often approached in a hierarchical fashion, with discrete abstractions and design methods used to satisfy high level task specifications, and continuous abstractions and design techniques used to satisfy low level control objectives. Although such a separation allows the application of mature theoretical and computational tools from the realms of computer science and control theory, the task of ensuring desired closed-loop behaviors, which results from the composition between discrete and continuous designs, often requires costly and time consuming verification and validation. This problem becomes especially acute in safety-critical applications, in which design specifications are often subject to rigorous industry standards and government regulations. Hybrid systems, which feature state trajectories evolving on a combination of discrete and continuous state spaces, have been proposed as a possible approach to reconcile the analysis and design techniques from the discrete and continuous domains under a rigorous theoretical framework. However, designing controllers for general classes of hybrid systems is a highly nontrivial task, as such a design problem inherits both the difficulty of nonlinear control, as well as the range of theoretical and computational issues introduced by the consideration of discrete switching.This dissertation describes several efforts aimed towards the development of theoretical analysis tools and computational synthesis techniques to facilitate the systematic design of feedback control policies satisfying safety and target attainability specifications with respect to subclasses of hybrid system models. The main types of problems we consider are safety/invariance problems, which involve keeping the closed-loop state trajectory within a safe set in the hybrid state space, and reach-avoid problems, which involve driving the state trajectory into a target set subject to a safety constraint. These problems are addressed within the context of continuous time switched nonlinear systems and discrete time stochastic hybrid systems, as motivated by application scenarios arising in autonomous vehicle control and air traffic management. First, we provide several design techniques and synthesis algorithms for deterministic reachability problems formulated in the setting of switched nonlinear systems, with controlled switches between discrete modes, and bounded continuous disturbances. For scenarios in which the mode transitions proceed in a known sequence, a method is discussed for designing controllers to satisfy sequential reachability specifications, consisting of a temporally ordered sequence of invariance and reach-avoid objectives. In particular, we use continuous time reachable sets to inform choices of feedback control policies within each discrete mode to satisfy both individual reachability objectives and compatibility conditions between successive modes. This technique is illustrated through an example of maneuver sequence design for automated aerial refueling of unmanned aerial vehicles. For scenarios in which the modes of a switched system can be freely selected, we describe an approach for the automated synthesis of feedback control policies achieving safety and reach-avoid objectives, under a sampled data setting. This synthesis technique proceeds by a structured reachability computation which retains information about the choice of switching controls at each discrete time instant, resulting in a set-valued policy represented in terms of a finite collection of reachable sets. Experimental results from the implementation of such control policies on a quadrotor platform to track a moving ground target show strong robustness properties in the presence of significant disturbances.Second, we provide theoretical and computational results on stochastic game and partial information formulations of probabilistic reachability problems. In the setting of a discrete time stochastic hybrid game model, zero-sum dynamic game formulations of probabilistic safety and reach-avoid problems are considered. Under an asymmetric information pattern favoring the adversary, we prove dynamic programming results for the computation of finite horizon max-min safety and reach-avoid probabilities and synthesis of deterministic max-min control policies. The implications of alternative information patterns and infinite horizon formulations are also discussed. In particular, it is shown that under a symmetric information pattern, equilibrium solutions are in general found within the class of randomized policies. The utility of this approach is illustrated through an example of pairwise aircraft conflict resolution, with a probabilistic model of wind effects. In the setting of a partially observable discrete time stochastic hybrid system, we provide a characterization of the optimal solution to partial information probabilistic safety and reach-avoid problems, which have nonstandard multiplicative and sum-multiplicative cost structures. In particular, these problems are shown to be equivalent to terminal cost and additive cost problems, by augmenting the hybrid state space with a binary random variable capturing the safety of past state evolution. Using this result, we derive a sufficient statistic in terms of a set of Bayesian filtering equations, along with an abstract dynamic programming algorithm for computing the optimal safety and reach-avoid probabilities. The practical implementation of the estimation and control algorithms, however, will depend on the existence of finite dimensional representations or approximations of the hybrid probability distribution.


Numerous studies have evaluated the effects of lockdowns during the COVID-19 pandemic, but most of them have concerned large cities and regions. This study aimed to evaluate the dynamics of air pollutants during and after the implementation of a short lockdown in the medium-sized city of Pelotas, Brazil, using hourly measurements of pollutants. The evaluation period included in this study was between August 9th and 12th, 2020. A machine learning model was used to investigate the expected behavior against what was observed during the study period. All pollutants presented a gradual reduction until a dynamic plateau established 48 hours after the start of the lockdown: NO2 (↓4%), O3 (↓34%), SO2 (↓24%), CO (↓48%), PM10 (↓82%) and PM2.5 (↓82%). At the end of the restriction measures, the PM10 and PM2.5 levels continued to decline beyond expectations. Our findings show that these measures can positively affect the air quality in medium-sized cities.


type="main"> This paper advocates abandoning null hypothesis statistical tests (NHST) in favour of reporting confidence intervals. The case against NHST, which has been made repeatedly in multiple disciplines and is growing in awareness and acceptance, is introduced and discussed. Accounting as an empirical research discipline appears to be the last of the research communities to face up to the inherent problems of significance test use and abuse. The paper encourages adoption of a meta-analysis approach which allows for the inclusion of replication studies in the assessment of evidence. This approach requires abandoning the typical NHST process and its reliance on p-values. However, given that NHST has deep roots and wide 'social acceptance' in the empirical testing community, modifications to NHST are suggested so as to partly counter the weakness of this statistical testing method.


A quick and simple test method for measuring the B-H curve and power loss in generator stators, both as loose laminations and finished core packs, has been developed. This provides a greater level of understanding about the characteristics of stator cores at various stages of the manufacturing process in order to prevent finished generators from being out of specification. The capabilities of the measurement rig have been explored both theoretically and experimentally. Experiments have been carried out on-site on industrially manufactured synchronous generators and permeability and power loss in a batch sample of stators have been measured. Considerable degradation in the steel's magnetic properties has been found. Mean permeability at 1 T decreased by 23% after compression and welding. For specific power loss, the welding process caused an increase of 5% in the mean value and an increase of 36% in the standard deviation. The results allow conclusions to be drawn regarding manufacturing effects, variability and generator performance.


Background The association between objectively assessed sedentary time and metabolic risk factors in childhood have rarely been studied. Therefore, we examined the independent relationship between objectively assessed and self-rated sedentary time and indicators of metabolic health in Dutch and Hungarian 10–12 year olds. Methodology/Principal Findings We performed a cross-sectional survey in primary schools. Participants were Dutch and Hungarian girls (n = 73, aged 12.2±0.6 years, 18% overweight/obese) and boys (n = 69, aged 12.2±0.7 years, 38% overweight/obese). Sedentary time and physical activity were assessed by the Actigraph accelerometer. TV and PC time were assessed by self-report. Adiposity indicators included body weight, height, and waist circumference (WC). Fasting plasma glucose, C-peptide, total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, and triglycerides were determined in capillary blood and summed into a metabolic risk score. Linear regression analyses were adjusted for physical activity, number of sedentary bouts and WC. Children spent on average 7.6 hours of their daily waking time in sedentary behavior and self-reported 116±64 min/day watching TV and 85±57 min/day using the computer. Comparing the 1st and 4th quartile of objectively assessed sedentary time, C-Peptide levels, WC and BMI were significantly higher in the most sedentary quartile, while the difference in metabolic risk score was borderline significant (p = 0.09). Comparing the 1st and 4th quartile of TV time, BMI was significantly higher in the most sedentary quartile, while the difference in WC score was borderline significant (p = 0.06). In the adjusted linear regression analysis we found no significant association of sedentary time with metabolic risk. Conclusions/Significance Although BMI and WC were higher in the most sedentary versus the least sedentary children; we found no further evidence that more sedentary children were at increased metabolic risk.


A multiplicative cascade can be thought of as a randomization of a measure on the boundary of a tree, constructed from an iid collection of random variables attached to the tree vertices. Given an initial measure with certain regularity properties, we construct a continuous time, measure-valued process whose value at each time is a cascade of the initial one. We do this by replacing the random variables on the vertices with independent increment processes satisfying certain moment assumptions. Our process has a Markov property: at any given time it is a cascade of the process at any earlier time by random variables that are independent of the past. It has the further advantage of being a martingale and, under certain extra conditions, it is also continuous. For Gaussian independent increments processes we develop the infinite-dimensional stochastic calculus that describes the evolution of the measure process, and use it to compute the optimal Hölder exponent in the Wasserstein distance on measures. We also discuss applications of this process to models of tree polymers and one-dimensional random geometry.


Objective. To describe the epidemiological impact of prenatal diagnosis and selective abortion on the frequency of neural tube defects (NTD) in the period 1980-1992 in the Northern Netherlands in comparison with data from other European regions. Design. Descriptive. Setting. 17 'European registration of congenital anomalies' (EUROCAT) registrations, localized in 10 European countries. Method. Data were collected actively and retrospectively from multiple sources fed by voluntary registration of congenital anomalies in live births, stillbirths and pregnancies terminated because of congenital anomalies. Results. In Europe the total birth prevalence of NTD in the period 1980-1992 ranged from 5.3 per 10,000 in Switzerland to 29.0 per 10,000 in Glasgow, a difference of a factor 5.5. In live births the difference was ninefold: ranging from 2,0 per 10,000 in Paris to 18.8 per 10,000 in Dublin. The Netherlands had a conspicuously high prevalence among live births, higher than in other regions in continental Europe. For spina bifida the live birth prevalence both in other continental regions and in Glasgow was also lower than in the Netherlands. In Glasgow serum alpha-foetoprotein screening apparently led to frequent early prenatal diagnosis of NTD and to frequent termination of pregnancy. In Paris the use of ultrasound screening appears to lead to frequent later prenatal diagnosis, as well as frequent termination of pregnancy. Conclusion. In the Netherlands the impact of prenatal diagnosis and selective abortion is limited, so that primary prevention (periconceptional use of folic acid) is more important than in some other European countries.


The p K a of a polyelectrolyte has been determined experimentally by potentiometric titration and computed using Molecular Dynamics (MD) constant pH (CpH) methodology, which allows the p K a of each titratable site along the polymer backbone to be determined separately, a procedure which is not possible by current experimental techniques. By using experimental results within the CpHMD method, the simulations show that the protonation states of neighbouring residues are anti-correlated so that the charges are well-separated. As found with previous simulation studies on model polyelectrolytes, the end groups are predicted to be the most acidic. CpHMD is shown to result in distinct polymer conformations, brought about by the range of protonation states changes along the polymer; this can now be used in the design of pH-responsive polymers for, amongst other applications, additive formulation and drug delivery devices.