Abstract This article examines predictors of depressive symptoms and caregiving burden in a sample of Cuban American and Puerto Rican caregivers of an adult child with mental retardation. Using a stress process model of caregiving, the focus of this analysis was on family role strains that result from the caregiving process, which were hypothesized to be particularly strong predictors of maternal well-being in Latino families. Findings indicate that Cuban American mothers of adults with mental retardation had higher socioeconomic status than Puerto Rican mothers, yet there was a substantial amount of within-group heterogeneity in family socio-demographic characteristics, linked closely with immigration patterns for the Cuban American mothers. However, taking into account socio-demographic diversity and ethnicity, findings demonstrate that mothers whose family had more problems had higher levels of burden and depressive symptoms, supporting the hypothesized importance of family functioning to Latina mothers with a non-normative parenting challenge.


Twenty-one patients with tumor stage mycosis fungoides (MF) with or without lymph node (LN) involvement, were treated with total skin electron beam irradiation (TSEB) followed by six monthly cycles of systemic chemotherapy (CT) of either mechlorethamine (HN2) or cyclophosphamide (CTX) with vincristine (VCR), procarbazine, and prednisone (PRD) (COPP or MOPP). All patients had complete clearing of the skin after TSEB. However, while receiving chemotherapy, two patients developed visceral involvement and eight patients relapsed with limited cutaneous plaques (LCP). The median duration of remission was 12 months from the completion of TSEB, and all patients relapsed with cutaneous plaques within 25 months. Complete remission was again achieved using additional electron irradiation and maintenance therapy in all but one patient. Multiple cutaneous recurrences occurred in all patients. Median survival from the initiation of TSEB is 6 years. Five patients are living beyond 8 years (four off treatment without disease for 1 to 7 years). LN involvement did not influence initial response or survival. Combined modality therapy for tumor stage MF using TSEB followed by systemic CT and subsequent maintenance therapy may lead eventually to prolonged disease-free survival (DFS) in selected patients.


This study examines the impact of food label use on diet quality of Americans. Using an endogenous switching regression model, results indicate that label use improves diet quality by as much 14 points on a 100 point Healthy Eating Index scale. The analysis also was conducted for each type of information contained on the labels: list of ingredients, nutrient content health claims, nutritional panel, serving size, and health benefit statements. Use of health benefit statements on food labels provides the highest level of improvement in diet quality.


Throughout the world there has been a desire to test mineral wool for the shredding of mineral fibers. There is a general concern, that sound absorption materials, consisting of fibers made of rock or glass, are damaging even in small amounts. Until now a standard method for the testing of acoustical absorbers has not been found. This paper shows a test chamber and describes a method for the objective measurement of shredded fibers. This method is simple and fast to carry out and shows a level of accuracy, which seems better than earlier attempts.


Click to zoom the map Imaging Homelessness in a City of Care was a participatory mapping project undertaken with 30 single homeless people in Newcastle-upon-Tyne (UK) in 2014. The project's objectives were threefold: to pilot an innovative mapping-based methodology; to offer single homeless individuals an opportunity to comment on local service provision and delivery; and to inform and challenge public perceptions of homelessness. In what follows, we outline the context for the project and the reasons for adopting a mapping approach. We then discuss the research process and the various insights generated. Finally, we reflect on the effectiveness of the methodology used.


Objective: We aim to determine the impact of steroid use in COVID-19 pneumonia in-hospital mortality. Design: We performed a single-centre retrospective cohort study. Setting: A University hospital in Madrid, Spain, during March 2020. Participants: Patients admitted with SARS-CoV-2 pneumonia. Exposures: Patients treated with steroids were compared to patients not treated with steroids. A propensity-score for steroid treatment was developed. Different steroid regimens were also compared, and adjusted with a second propensity score. Main Outcomes and Measures: To determine the role of steroids in in-hospital mortality, univariable and multivariable analyses were performed, and adjusted including the propensity score as a covariate. Survival times were compared using a log-rank test. Results: During the study period, 463 out of 848 hospitalized patients with COVID19 pneumonia fulfilled inclusion criteria. Among them, 396 (46.7%) consecutive patients were treated with steroids and 67 patients were assigned to the control cohort. Global mortality was 15.1%. Median time to steroid treatment from symptom onset was 10 days (IQR 8 to13). In-hospital mortality was lower in patients treated with steroids than in controls (13.9% [55/396] versus 23.9% [16/67], OR 0.51 [0.27 to 0.96], p= 0.044). Steroid treatment reduced mortality by 41.8% relative to no steroid treatment (RRR 0,42 [0.048 to 0.65). Initial treatment with 1 mg/kg/day of methylprednisolone (or equivalent) versus steroid pulses was not associated with in-hospital mortality (13.5% [42/310] versus 15.1% [13/86], OR 0.880 [0.449-1.726], p=0.710). Conclusions: Our results show that survival of patients with SARS-CoV2 pneumonia is higher in patients treated with glucocorticoids than in those not treated. In-hospital mortality was not different between initial regimens of 1 mg/kg/day of methylprednisolone or equivalent and glucocorticoid pulses. These results support the use of glucocorticoids in SARS-CoV2 infection.


We show that existing methods for training preposition error correction systems, whether using well-edited text or error-annotated corpora, do not generalize across very different test sets. We present a new, large errorannotated corpus and use it to train systems that generalize across three different test sets, each from a different domain and with different error characteristics. This new corpus is automatically extracted from Wikipedia revisions and contains over one million instances of preposition corrections.


Environmental, social, and governance (ESG) standards do not permit complicity in modern slavery, human trafficking, or child labor (Principles for Responsible Investment [PRI] 2021, 4). And yet, the breadth and depth of oppressive labor practices in US and global corporate supply chains is, in a word, staggering. Across industry and geographic boundaries, throughout corporate America and the world, modern slavery, human trafficking, and child labor support a myriad of goods and services produced, supplied, and consumed daily. The coffee you drank this morning; the car in your driveway; the shirt, pants, dress, or shoes you're wearing; the phone in your hand and computer on your desk; the salad you might have had yesterday and the shrimp you may be served tonight; the hotel room prepared for your recent night's sleep and chocolate on your bedside; the mask you've been wearing because of COVID-19—all may have been grown, harvested, mined, sewn, or assembled, in part, by adults and children, some as young as four or five, compelled to work unwillingly under threat of bodily harm, torture, or even death.

Modern slavery, human trafficking, and child labor, which we label for this paper "oppressive labor", is a global societal problem demanding a strong public reaction from responsible investors. Investing in companies harvesting oppressive labor is neither ethically nor morally responsible, contravenes fundamental notions of social justice contained in modern ESG standards, and may result in disappointing financial performance in those companies found to be so engaged. Investors wishing to follow ESG best practices should disinvest from companies whose supply chains are linked to oppressive labor practices. We construct oppression-free portfolios with acceptable tracking errors to four popular indexes.


The aim of this paper is to report the data concerning the contamination of the exhausted air from the hot cells dedicated to the large-scale synthesis of positron emission tomography (PET) radiopharmaceuticals. Two cyclotrons are currently operating in Ospedale San Raffaele for the routine production of 11C and 18F. They are linked with four radiochemistry laboratories by means of shielded radioisotope delivery lines. The above labs are dedicated both to the large scale preparation and to the research and development of PET radiopharmaceuticals. The department hosts four CT-PET scanners, which operate with a mean patient workload of 40 per day. Radiosyntheses are performed using automated modules located in 10 hot cells. The air outlets are monitored online by a 2-inch NaI(Tl) counter in a Marinelli geometry counting volume. Contamination values up to 105 Bq L−1 have been measured at the hot cell exit point during the synthesis. The corresponding concentrations at the point of release in atmosphere are largely above the threshold of 1.29 Bq L−1, defined by national regulations as the limit for free environmental release. A shielded gas storage system controlled by a dedicated, customized software program has thus been installed to prevent the potentially hazardous release of gaseous radioactive contaminants. The system has allowed us to maintain the effective dose to neighboring population groups below the limit of 10 &mgr;Sv y−1.


Recent exhibition attempts to recuperate and revise Conceptual Art — 'Open Systems' (2005),
'Invisible: Art About the Unseen' (2012) — have brought to the fore wider discursive
concerns regarding coding, interfaces and artistic intentionality. Taking its lead from Rosalind
Krauss' seminal work on the post-medium condition, this paper argues that the continued
privileging of interface/display-user inherent within artistic discourse belies a more nuanced
reading of the critical relationship between artist and code. Furthermore, this paper explores
new practices in Computer Art and its related theorisation by Tanaka-Ishii and Dominic
Lopes, with a view to re-conceptualising the relationship between artistic intentionality,
coding, interface and user input. Based on this re-conceptualisation we identify the 'postdisplay
condition of contemporary computer art', a condition that neither privileges userdisplay
communication, nor the space between code and user, but rather envelopes meaning
production between all elements of an artwork.


In agriculture sector where farmers and agribusinesses have to make innumerable decisions every day and intricate complexities involves the various factors influencing them. An essential issue for agricultural planning intention is the accurate yield estimation for the numerous crops involved in the planning. Data mining techniques are necessary approach for accomplishing practical and effective solutions for this problem. Agriculture has been an obvious target for big data. Environmental conditions, variability in soil, input levels, combinations and commodity prices have made it all the more relevant for farmers to use information and get help to make critical farming decisions. This paper focuses on the analysis of the agriculture data and finding optimal parameters to maximize the crop production using Machine learning techniques like random forest regressor and Linear Regression. Mining the large amount of existing crop, soil and climatic data, and analysing new, non-experimental data optimizes the production and makes agriculture more resilient to climatic change.


Abstract After 35 years, exploration in and around Britain has reached a mature stage. Pure oil and gas exploration has with certain exceptions given way to the search for small fields close to infrastructure and maximizing recovery from existing fields. To examine the lessons of 35 years of exploration before many of the major players leave the stage is opportune. Lessons learned can be applied elsewhere. An examination of the history suggests that lessons can be grouped under four headings: organization, technical skills, personal qualities and tactics. Successful companies optimize all of these. Unsuccessful companies, on the other hand, often fail because of a particular flaw in one of them. It is concluded that successful exploration companies would field a team captained by a technically competent open-minded manager closely linked to skilled geoscientists, all of whom would have a deep understanding (through relatively long service) of the area being explored. Both managers and geoscientists would be able to take sensible risks and would not confuse the primary concern of the technical merits of a prospect with the secondary concern of the economics of success. Finally, luck appears to play an important part but there is no doubt that successful companies work hard for their luck. Other lessons centre on the quirkiness of individual behaviour. This is something that no amount of study can eliminate.


A novel design for a rapid clean-up method was developed for the analysis of pesticide residues in fruit and vegetables followed by LC-ESI-MS/MS. The acetonitrile-based sample extraction technique was used to obtain the extracts, and further clean-up was carried out by applying the streamlined procedure on a multiplug filtration clean-up column coupled with a syringe. The sorbent used for clean-up in this research is multiwalled carbon nanotubes, which was mixed with anhydrous magnesium sulfate to remove water from the extracts. This method was validated on 40 representative pesticides and apple, cabbage, and potato sample matrices spiked at two concentration levels of 10 and 100 μg/kg. It exhibited recoveries between 71 and 117% for most pesticides with RSDs < 15%. Matrix-matched calibrations were performed with the coefficients of determination >0.995 for most studied pesticides between concentration levels of 10-500 μg/L. The LOQs for 40 pesticides ranged from 2 to 50 μg/kg. The developed method was successfully applied to the determination of pesticide residues in market fruit and vegetable samples.


Data science is a new field that integrates aspects of computer science, statistics and information management. As a new field, ethical issues a data scientist may encounter have received little attention to date, and ethics training within a data science curriculum has received even less attention. To address this gap, this article explores the different codes of conduct and ethics frameworks related to data science. We compare this analysis with the results of a systematic literature review focusing on ethics in data science. Our analysis identified twelve key ethics areas that should be included within a data science ethics curriculum. Our research notes that none of the existing codes or frameworks covers all of the identified themes. Data science educators and program coordinators can use our results as a way to identify key ethical concepts that can be introduced within a data science program.


This dissertation deals with three topics in descriptive set theory. First, the order topology is a natural topology on ordinals. In Chapter 2, a complete classification of order topologies on ordinals up to Borel isomorphism is given, answering a question of Benedikt Lowe. Second, a map between separable metrizable spaces X and Y preserves complete metrizability if Y is completely metrizable whenever X is; the map is resolvable if the image of every open (closed) set in X is resolvable in Y. In Chapter 3, it is proven that resolvable maps preserve complete metrizability, generalizing results of Sierpinski, Vainštein, and Ostrovsky. Third, an equivalence relation on a Polish space has the Laczkovich-Komjath property if the following holds: for every sequence of analytic sets such that the limit superior along any infinite set of indices meets uncountably many equivalence classes, there is an infinite subsequence such that the intersection of these sets contains a perfect set of pairwise inequivalent elements. In Chapter 4, it is shown that every coanalytic equivalence relation has the Laczkovich-Komjath property, extending a theorem of Balcerzak and Gląb.


The enteric microbiota is characterised by a balance and composition that is unique to the host. It is important to understand the mechanisms through which the host can maintain the composition of the gut microbiota. MicroRNAs (miRNA) are implicated in intercellular communication and have been isolated from bodily fluids including stool. Recent findings suggest that miRNA produced by the host's intestinal epithelial cells (IECs) participate in shaping the microbiota. To investigate whether miRNA expression was influenced by the gut microbiota we measured the expression of miRNAs expressed by intestinal epithelial cells in faeces. Specifically, we measured miRNA expression in faeces from germ-free (GF) and conventional mice and similarly in a rat model of antibiotic-mediated depletion of the gut microbiota control rats. In adult male GF and conventional mice and adult Sprague Dawley (SD) rats were treated with a combination of antibiotics for 8 weeks; total RNA was extracted from faecal pellets taken at week 0, 2, 4, 6 week 8 and the expression of let-7b-3p, miR-141-3p, miR-200a-3p and miR-1224-5p (miRNAs known to be expressed in IECs) were measured relative to U6 at each time point using qRT-PCR. In GF animals the expression of let-7b, miR-141 and miR-200a in faeces was lower compared to conventional mice. Following antibiotic-mediated depletion of gut microbiota, rats showed two divergent profiles of miRNA expression. Following two weeks of antibiotic treatment, the expression of let-7b and miR-1224 dropped significantly and remained low for the remainder of the study. The expression of miR-200a and miR-141 was significantly higher at week 2 than before antibiotic treatment commenced. Subsequently, the expression of miR-200a and miR-141 decreased at week 4 and continued to decrease at week 6. This data demonstrates that miRNAs can be used as an independent, non-invasive marker of microbial fluctuations along with gut pathology in the intestine.


ABSTRACT Managers in many public domains have to meet major challenges today, which is why it is essential to focus on their working conditions in order to develop a sustainable situation. In the present study, the aim was to explore different types of managerial situations and how they discriminate in health, motivation, and performance outcomes. Using the job demands-resources model as a framework, four demands and three resources were included in a cluster analysis in order to answer the research question. In total, 548 managers in Sweden participated, including heads of department, middle managers, firstline managers, team leaders, and functional managers. The most important finding was that the eight clusters of managerial situations that were found discriminated in a distinct way against each other regarding health, motivation, and performance. The results can be used as guidance for organizational intervention as both very satisfactory and very unsatisfactory situations are identified.


Inter-organizational cost management is a strategic cost management approach to managing costs that span organizational boundaries in supply chains. Drawing on the resourcebased view of the firm, we develop a model to predict which inter-related resources might enable companies to manage inter-organizational costs. We test this model using a survey of managerial accountants whose organizations are part of a supply chain. Using structural equation modeling, we conclude that the resources of internal electronic integration, external electronic integration, internal cost management, and absorptive capacity play significant direct and indirect roles in the development of an inter-organizational cost management (IOCM) resource. We find that these resources are inter-related and together are useful in enabling companies to ultimately benefit from managing inter-organizational costs. We find in particular the importance of relational resources associated with absorptive capacity in the development of an IOCM resource. Our research contributes to theory and practice by explaining how specific resources can be combined in allowing companies to better manage inter-organizational costs. Data were analyzed using SEM with the aid SmartPLS software version 3.0


The key challenge of spectrum sensing is the Detection of weak signals or primary user in noise with a very small probability of miss detection, which requires better understanding of very low SNR regimes. Cognitive radio allows unlicensed users to access licensed frequency bands through dynamic spectrum access so as to reduce spectrum scarcity. The spectrum sensing problem has gained new aspects with cognitive radio and opportunistic spectrum access concepts. It is one of the most challenging issues in cognitive radio systems; the paper explains sensing concept and its various Techniques. First cognitive radio standard called the Wireless Regional Area Network (WRAN). In additional to conventional PHY and MAC layer functionalities, new features have been included in IEEE 802.22 standards. These features are Spectrum Sensing and Spectrum Management. KeywordsCognitive radio, IEEE 802.22, Cyclo Stationary Detection, Spectrum Sensing


Objective: To investigate acute anterior knee pain caused by overuse in terms of pain location, aggravating activities, findings on clinical examination and ultrasound/MRI examination. To determine if acute anterior knee pain caused by overuse should be classified as a subgroup of patellofemoral pain syndrome (PFPS). Methods: In a observational study design 30 army recruits with anterior knee pain (mean duration of pain 4 weeks) were examined using the PFPS pain severity scale (PSS), knee pain diagrams, standardised clinical examination, ultrasound and MRI examinations. Results: On PSS typical knee loading activities were the most painful, while sitting with knee bend for prolonged time caused surprisingly little pain. Pain was most commonly perceived in the peripatellar area (25 patients (83%)). The most common site of pain on clinical examination was the peripatellar area (25 patients (83%)), but other synovial covered structures including the fat pad of Hoffa (12 patients (40%)), the medial plica and the joint line (12 patients (40%)) were also involved. Only eight patients (27%) experienced pain on the patellofemoral compression test. Only discrete changes was detected on MRI/ultrasound. Conclusions: Acute anterior knee pain should be regarded as a subgroup of PFPS as both symptoms and clinical examination suggests this. The clinical examination with disseminated pain in all synovial covered structures is consistent with ideas of the importance of synovium in the genesis of pain.


Background Hepatocellular cancer is the commonest liver cancer which contributes to a high incidence of morbidity and mortality in both developed and developing countries. Despite the anticipated high burden of the disease in the country, there is paucity of data on the associated risk factors and its pattern on imaging. The aim of this study was to assess Computed Tomography patterns and the risk factors of hepatocellular carcinoma. Methods A cross-sectional, prospective study on patients with a diagnosis of HCC on Computed Tomography examination, at Tikur Anbessa Specialized Hospital from July, 2016 to July, 2017. All patients who had characteristic Computed Tomography features and those who were diagnosed by Fine needle aspiration cytology (FNAC)/biopsy and had Computed Tomography examination were included in the study. Risk factors identified were reviewed from patients' medical records. Result A total of 70(n=70) patients were included in the study. The mean age was 50 ± 16 years. Fifty-seven (81.4%) of the participants were males, and 13(18.6%) were females. Forty-five (64.3%) of them came from urban areas and 25(35.7%) of them were from rural areas. The lesions were focal in 52(74.3%) and infiltrative in 18(25.7%) of the cases. Vascular invasion and distant metastases were seen in 49(70%) and 17(24.3%) respectively. Twenty-nine (41%) had negative hepatitis markers, and 13(19%) were not investigated for hepatitis infection. Conclusion The majority of the patients presented with advanced disease such as vascular invasion and metastases. The major risk factors such as hepatitis infection were negative in significant number of patients. The risk factors in our setting should be studied further. Moreover, high-risk group selection and screening is essential to diagnose HCC early.


Building portable parallel programs on distributed memory multiprocessors and workstation networks is a complex task that is greatly facilitated by powerful infrastructure. In this dissertation, we develop important components of that infrastructure, focusing on irregular applications such as unstructured mesh computations, search problems, and discrete event simulation. We use a library-based approach to building such applications. The library provides a uniform programming interface on multiple platforms and has highly tuned implementations developed by the library programmer. Therefore, applications built on the library can be portable both in functionality and in performance.
We describe the major components of our parallel data structure library called Multipol, including two of the more irregular data structures and one application. The two data structures are a task stealer for dynamic load balancing and an event graph for discrete event simulation. The application is a timing-level circuit simulator for combinational circuits. We analyze the workloads of several applications built by the Multipol group and quantitatively characterize their irregularities.
The Multipol library is built on a runtime layer consisting of threads as well as communication mechanisms. The thread layer supports a basic computational abstraction called fibers, which are code sequences that appear to execute atomically. The fiber abstraction enables a portable multithreading execution environment for latency hiding. The thread layer also allows the programmer to supply customized schedulers to enforce application-specific scheduling policies. The communication layer provides portable primitives for expressing irregular communication. It uses a technique called message aggregation to trade the excess parallelism in the application for better communication bandwidth.
We provide a new performance profiling toolkit called Mprof to help tune the performance of irregular parallel programs. Mprof identifies two major sources of performance inefficiency: overhead and insufficient parallelism. It uses statistical modeling to extract reusable cost models from benchmark executions. The cost models are combined with high-level statistics collected from an actual execution to provide low-overhead profiling information. Mprof also provides a performance interface for the library programmer to customize the profiling information and thereby preserve the library abstraction. Using information from Mprof, we optimize the performance of several irregular applications and demonstrate the performance portability of the Multipol library and runtime layer.


The meaning of counterfactual conditionals is standardly described using the similarity approach (Stalnaker, 1968; Lewis, 1973). This approach has recently been challenged by Ciardelli et al. (2018). They argue that the similarity approach is in principle unable to account for the meaning of counterfactuals with an antecedent consisting of a conjunction embedded under a negation (¬(p^q)). Ciardelli et al. (2018) dismiss the approach on these grounds and offer an alternative. The main goal of the present paper is to defend the similarity approach against this attack. I will argue that the problem that underlies the observations in Ciardelli et al. 2018 is more general and not solved by the solution they offer. I will furthermore argue, against Ciardelli et al. (2018), that the cause of the problem is not the similarity approach, but the interaction of negation with the meaning of counterfactual conditionals. The paper will conclude with a first outline of a solution for the problem, which still uses the similarity approach, but combines it with an alternative semantics for negation.


Dakota County in southeastern Minnesota provides unique exhibits for the study of Pleistocene drifts derived from north and northwest of the Lake Superior region.

No known Nebraskan till was found, but the Kansan is exposed in road cuts in the central and western parts of the county. The surficial geology consists of tills of Illinoian, Early Wisconsin (Iowan), and Late Wisconsin (Cary of both Keewatin and Patrician origins and Mankato) ages and extensive areas of outwash.

The stratigraphic relationships of the once much-disputed Iowan to the Illinoian and the Illinoian to the Kansan are revealed in road cuts in the west.

Post-Iowan tills are restricted to the north and west. The terms "Keewatin" and "Patrician" are retained to indicate the sources of the Cary drifts.


The poems in Circles Where the Head Should Be are full of objects and oddities, bits of news, epic catalogues, and a cast of characters hoping to make sense of it all. Underneath the often whimsical surface, however, lies a search for those connections we long for but so often miss, and a wish for art to bridge the gaps. "Circles Where the Head Should Be has its own distinctive voice, a lively intelligence, insatiable curiosity, and a decided command of form. These qualities play off one another in ways that instruct and delight. An irresistible book."—J. D. McClatchy, author of Mercury Dressing: Poems, judge


Anisotropic triangular graphene monolayers grown on a Ru(0001) surface represent unique two-dimensional templates for creating ordered, large-scale assembly of functional molecules. Using scanning tunneling microscopy and spectroscopy, we demonstrate the selective adsorption and the formation of ordered molecular arrays of iron phthalocyanine and pentacene molecules of different structural symmetries on the graphene/Ru(0001) templates. With in-depth investigations of the molecular adsorption and assembly processes, we reveal the existence of site-specific, lateral electric dipoles (or lateral electric fields) in the epitaxial graphene monolayers and the capability of the dipoles in directing and driving the molecular adsorption and assembly. We show that the lateral dipoles originate from the inhomogeneous distribution of charge due to the epitaxial constraint of graphene on a Ru(0001) surface. The adsorption mechanism is rather general and applicable to similar molecular systems on graphene monolayers formed on other transition metal surfaces.


Thin magnetic film switching was investigated for fields near those needed for pure rotation. Experimentally the films were switched using <0.4 ns rise time field pulses. The resulting flux changes were detected in the easy and hard direction with a response time of 0.6 ns. Measurements were made for pulses both longer and shorter than the magnetization switching times. By analyzing the voltage waveforms and flux changes, it was concluded that instabilities and rapid rearrangements of the magnetization can occur within a few nanoseconds, causing anomalous results during switching. Equations of existing quantitative switching models-pure rotation, spin-wave, and stripe domain-were solved with a digital computer. To better compare theory and experiment, the solutions were modified to account for the sense system's finite rise time. It was found that none of the existing models adequately described the switching processes for low amplitude magnetic fields. However, qualitatively, the stripe domain model best fit the experimental data.


We examined the effects of an inhaled glucocorticosteroid, budesonide, on antigen-induced early and late bronchial responses and the development 24 h after challenge of increased airway responsiveness to carbachol in allergic sheep. Six allergic sheep were used for this study and, on occasions separated by at least three weeks, they were treated: with placebo (treatment 1); 16 h and 20 min prior to antigen challenge with budesonide (treatment 2); 16 h and 20 min prior to and 8 h after antigen challenge with budesonide (treatment 3); or 16 h and 1 h prior to and 8 h after antigen challenge with budesonide (treatment 4). Airway responsiveness to carbachol was determined prior to and 24 h after antigen challenge by measuring specific lung resistance (sRL) after administering increasing doses of carbachol aerosol (0.5, 1 and 2.5% w/v) and determining the concentration of carbachol needed to increase sRL 150% over baseline (PC150). Placebo treatment did not affect the early or late increases in sRL after airway challenge with Ascaris suum antigen; 24 h after challenge, airway responsiveness to carbachol increased (p less than 0.05); at this time, PC150 was (mean +/- SEM) 0.88 +/- 0.15% as compared to 1.56 +/- 0.26% before challenge. Both treatments 2 and 3 blunted the early response to antigen and blocked the late response, but treatment 2 did not modify the antigen-induced increase in airway responsiveness, whereas treatment 3 did. Treatment 4 blocked both antigen-induced responses and was effective in blunting the increased airway responsiveness. These results suggest that antigen-induced increases in airway responsiveness: occur 24 h after a challenge in allergic sheep with early and late responses; can be blunted by budesonide; and are not dependent on the late response.


Writing this has been a troubling experience. Returning to a text 30 years on in this way combines intellectual, political and personal reflections in an unsettling way. These range from a powerful attachment to processes of collective or collaborative intellectual work that Policing the Crisis (PTC; Hall et al., 1978) embodied and enhanced to a rather depressed sense of how many things the book got right about the trajectory of the British social formation in the mid 1970s (other futures might have been preferable). And above all, there is a sense of what the book stands for in the emergence of cultural studies as an institutionalized academic field. As a way of trying to digest these different responses, I have tried to address three sorts of questions: why PTC mattered, where it belongs and why it continues to have echoes in the present.


In this paper, we propose a generalization of the level set segmentation approach by supplying a novel method for adaptive estimation of active contour parameters. The presented segmentation method is fully automatic once the lesion has been detected. First, the location of the level set contour relative to the lesion is estimated using a convolutional neural network (CNN). The CNN has two convolutional layers for feature extraction, which lead into dense layers for classification. Second, the output CNN probabilities are then used to adaptively calculate the parameters of the active contour functional during the segmentation process. Finally, the adaptive window size surrounding each contour point is re-estimated by an iterative process that considers lesion size and spatial texture. We demonstrate the capabilities of our method on a dataset of 164 MRI and 112 CT images of liver lesions that includes low contrast and heterogeneous lesions as well as noisy images. To illustrate the strength of our method, we evaluated it against state of the art CNN-based and active contour techniques. For all cases, our method, as assessed by Dice similarity coefficients, performed significantly better than currently available methods. An average Dice improvement of 0.27 was found across the entire dataset over all comparisons. We also analyzed two challenging subsets of lesions and obtained a significant Dice improvement of 0.24 with our method (p <0.001, Wilcoxon).


Cancer risk is increased substantially in adult kidney transplant recipients, but the long‐term risk of cancer in childhood recipients is unclear. Using the Australian and New Zealand Dialysis and Transplant Registry, the authors compared overall and site‐specific incidences of cancer after transplantation in childhood recipients with population‐based data by using standardized incidence ratios (SIRs). Among 1734 childhood recipients (median age 14 years, 57% male, 85% white), 289 (16.7%) developed cancer (196 nonmelanoma skin cancers, 143 nonskin cancers) over a median follow‐up of 13.4 years. The 25‐year cumulative incidences of any cancer were 27% (95% confidence intervals 24–30%), 20% (17–23%) for nonmelanoma skin cancer, and 14% (12–17%) for nonskin cancer (including melanoma). The SIR for nonskin cancer was 8.23 (95% CI 6.92–9.73), with the highest risk for posttransplant lymphoproliferative disease (SIR 45.80, 95% CI 32.71–62.44) and cervical cancer (29.4, 95% CI 17.5–46.5). Increasing age at transplantation (adjusted hazard ratio [aHR] per year 1.10, 95% CI 1.06–1.14), white race (aHR 3.36, 95% CI 1.61–6.79), and having a functioning transplant (aHR 2.27, 95% CI 1.47–3.71) were risk factors for cancer. Cancer risk, particularly for virus‐related cancers, is increased substantially after kidney transplantation during childhood.


South Korea is well known for its distinctive, sometimes excessive, enthusiasm for education. This education fever is derived from South Koreans' concern with the pursuit of education as a way of achieving socioeconomic status and power, and thus, competitions to score well on tests have been valorized in South Korea. Now that English has become the language of power and opportunity in South Korea, this paper aims to examine how education fever has promoted de facto English language policy over top-down English language policy. By referring to Cooper's (1989) and Kaplan and Baldauf 's (1997) frameworks, this paper interprets private education in South Korea as de facto policy, which exercises greater influence on how language policy is developed in practice than a top-down statement can. This article is available in Working Papers in Educational Linguistics (WPEL): http://repository.upenn.edu/wpel/vol30/iss1/5 Private Education as De Facto Language Policy in South Korea


In the literature of learner characteristics in applied linguistics, learning attitudes, strategies and motivation have received most attention. These learner individual difference variables have usually been seen as background learner variables that modify and personalize the overall trajectory of the language acquisition processes (Dörnyei, 2009). Embedded within a mainly psycholinguistic perspective on L2 acquisition, previous research on these background learner variables tended to examine one variable independently of other variables, and of the learning contexts in which L2 learners are situated (Ellis, 2004). For example, early studies on good language learners focused largely on learning strategies. Consequently much less attention has been given to the interplay between various individual difference factors as well as interaction between learner individual and contextual factors. This case study set out to investigate how the contextualized learner learning attitudes, strategies, and motivation might differentiate successful and less successful ESL learners. Data were collected through interviews, diaries, and follow-up email correspondence with both successful and less successful second-year university ESL students. Analysis of the data suggests that learners' psychological relation to the English language learning process depends in large measure upon the social, institutional, and interpersonal contexts "in which individuals find themselves, the purposes for their being there, and their personal biographies" (Duff & Uchida, 1997, p. 452). Learners' investment in English language learning and different levels of success as ESL learners could thus be the outcome of dynamic interactions of different learner factors situated in the particular learning contexts. Implications of the results for how institutions and teachers may empower ESL students in their investment in learning the target language are discussed.


Abstract. The energy of a laser beam irradiating a surface is primarily absorbed by electrons within the solid. In actual transparent materials, absorption is low. High-intensity lasers may, however, be absorbed by initially bounded electrons through nonlinear processes. The increase of free-electron density leads eventually to dielectric breakdown, and the material becomes highly absorbing. We present theoretical studies on the dynamics of electrons in dielectrics under irradiation with a visible high-intensity laser pulse. We consider microscopic processes determining absorption, redistribution of the energy among electrons, and transfer of energy to the crystal lattice. We review different aspects of electronic excitation, studied with time-resolved models as the Boltzmann kinetic approach and the time and spatial resolved multiple rate equation. Furthermore, we investigate criteria for damage thresholds. Two concepts are compared, namely a critical free-electron density and the melting threshold of the lattice. We show that in dielectrics both criteria are fulfilled simultaneously. Optical parameters depend on the density of free electrons in the conduction band of the solid, so the free-electron density directly leads to an increased energy absorption causing material modification. We present results on the spatial dependence of dielectric breakdown.


Kinetic data of 1-pentanol dehydration on γ-alumina catalyst modified by potassium hydroxide were obtained using a continuous reactor with an internal recirculation. The conversion of 1-pentanol on this catalyst in the temperature range 300 - 390 °C and space velocity 1 - 8 kg (h kg)-1 (molar fraction of water in the feed was in the range 0 - 0.56) was 50 - 98% and the selectivity with respect to 1-pentene was 50 - 84%. The following six reactions have been taken into account to describe the catalytic dehydration of 1-pantanol: direct formation of 1-pentene from 1-pentanol, formation of bis(1-pentyl) ether from 1-pentanol, disproportionation of the ether to 1-pentanol and 1-pentene, formation of 1-pentene from the ether, isomerization of 1-pentene to 2-pentene and hydrolysis of the ether to 1-pentanol. Treatment of experimental data by Langmuir-Hinshelwood models showed that the model involving adsorption of 1-pentanol accompanied by dissociation is the most suitable one.


The traditional approach of landscape architecture has always focused on the aesthetic and visual aspects of landscapes while giving less attention to other aspects. This view has limited the benefits that can be derived from designed landscapes, despite the wide-ranging potential they carry for humans; socially, environmentally and economically. As a result, many researchers and practitioners are currently challenging this view to develop a more holistic and multidimensional approach. The present research therefore aims at proposing a new perspective for public designed landscapes based on fundamental human needs. The study methodology was comprised of critical content analysis for three main domains: sustainable development, human needs in specific relation to public landscapes, and significant approaches to fundamental human needs. Reconciliation among these domains was achieved based on a modified version of Max-Neef's matrix of fundamental human needs. Human needs in public landscapes were merged into the matrix to reach a comprehensive yet specific perspective. The study concluded with a conceptual framework that can provide a wider perspective to human needs in designed landscapes. It proposes a new tool for the analysis of the benefits of public landscapes and their value for humans, which can be further used in various applications.


This datasheet on Leucaena diversifolia covers Identity, Overview, Distribution, Dispersal, Diagnosis, Biology & Ecology, Environmental Requirements, Natural Enemies, Impacts, Uses, Prevention/Control, Management, Genetics and Breeding, Economics, Further Information.


Over the century-long period from just before the American Revolution until the end of the Civil War the United States underwent a profound transformation, beginning with its political break from Britain and expanding rapidly to embrace political and economic liberalism and elements of equality and social justice. Importantly, this transformation was aided by fundamental changes to the received English common law of property. Several property-law changes enhanced economic freedom and facilitated industrialization. Other legal changes diminished the power of landowners to dominate the poor socially and economically. Yet further reforms stabilized land tenure and expanded easy public access to natural resources, on private as well as public lands. Along the way, American courts embraced a more instrumental conception of law and carved out greater space for legislatures to regulate uses of property. Many of these changes involved substantial shifts of wealth, yet none was accompanied by significant compensation. In its transformation, South Africa is differently situated from the US of two centuries ago. Nonetheless, the American record may prove instructive, both in its particulars and as an example of how a developing nation, committed to private property and the rule of law, can nonetheless reform the legal elements of ownership without diminishing the institution's stability and widespread benefits.


Lenin's State and Revolution was one of the most famous texts of the twentieth century. Written in 1917 before the October revolution and published shortly after, it looked forward to a new polity, one that should be fully democratic, with a 'dictatorship of the proletariat' creating 'democracy for the people'. His discussion assumed that a Marxist party's thinking should predominate. He did not consider differences between artisan Paris in 1871, and industrial St. Petersburg and Moscow in 1917; between the older (commune) and newer forms of mass participatory organisation. He did not consider the pressing issues of what role factory committees might play, how they might relate to unions, Soviets and other structures, and how these various organisations could work together. Lenin often took his cue from the German model of social democracy before the war. Notably, in State and Revolution he still refers to the German post office – under socialist guidance – as a model, without noting the post office's hierarchal status-proud culture, with officials recruited from the army; ex-soldiers inured to military discipline. It is telling that he refers to beamte (state officials delivering letters) proud of their status, rather than organised workers. Lenin called for the destruction of autocratic and parliamentary state forms. But he also admired orderly hierarchies. So State and Revolution contains diverse and somewhat contradictory elements. The October revolution brought such diverse elements to the fore; moreover, as it developed the substance and weight of various elements – old and new – changed, and so too did the interrelation between them. These dynamics were both complex and somewhat unprecedented: there was no single road map for the transition towards socialism, rather several sketchy 'maps' with diverse and somewhat inconsistent signposts.


Now that ever more sophisticated devices for quantum computing are being developed, we require ever more sophisticated benchmarks. This includes a need to determine how well these devices support the techniques required for quantum error correction. In this paper we introduce the topological_codes module of Qiskit-Ignis, which is designed to provide the tools necessary to perform such tests. Specifically, we use the RepetitionCode and GraphDecoder classes to run tests based on the repetition code and process the results. As an example, data from a 43 qubit code running on IBM's Rochester device is presented.


Fermi-Löwdin orbitals (FLOs) are a special set of localized orbitals, which have become commonly used in combination with the Perdew-Zunger self-interaction correction (SIC) in the FLO-SIC method. The FLOs are obtained for a set of occupied orbitals by specifying a classical position for each electron. These positions are known as Fermi-orbital descriptors (FODs), and they have a clear relation to chemical bonding. In this study, we show how FLOs and FODs can be used to initialize, interpret, and justify SIC solutions in a common chemical picture, both within FLO-SIC and in traditional variational SIC, and to locate distinct local minima in either of these approaches. We demonstrate that FLOs based on Lewis theory lead to symmetry breaking for benzene-the electron density is found to break symmetry already at the symmetric molecular structure-while ones from Linnett's double-quartet theory reproduce symmetric electron densities and molecular geometries. Introducing a benchmark set of 16 planar cyclic molecules, we show that using Lewis theory as the starting point can lead to artifactual dipole moments of up to 1 D, while Linnett SIC dipole moments are in better agreement with experimental values. We suggest using the dipole moment as a diagnostic of symmetry breaking in SIC and monitoring it in all SIC calculations. We show that Linnett structures can often be seen as superpositions of Lewis structures and propose Linnett structures as a simple way to describe aromatic systems in SIC with reduced symmetry breaking. The role of hovering FODs is also briefly discussed.


Problem statement: Mobile Ta'ziyeh is regarded as one of the kinds of traditional Iranian theatre in which the scenes are performed not in a permanent place, but on a certain path. The present study aims to investigate how the discourse of Ta'ziyeh is formed in connection with the displacement of spatial boundaries and how this displacement emerges as a process that turns Ta'ziyeh into a performance with transformative function. In the current article, the interaction between the discourse of Ziaber Mobile Ta'ziyeh (case study) and the discourse of the city is studied. Also, the effects of performing Ta'ziyeh on the urban areas of Ziaber are investigated semiotically. Research objectives: The main purpose of this article is to identify the semiotic aspects of mobility in the Ta'ziyeh and its function in the transformation of urban places and spaces. Research method: The present article has been conducted through a qualitative method based on the Paris school semiotics. The research approach is derived from post-Gremassian tradition and is the result of the transition from structuralist and classical semiotics to semiotics based on "body", "perception" and "presence" with a phenomenological background. Conclusion: The course of Ta'ziyeh Ziaber is formed by joining the three main locations of this city (cemetery, the main street, and house of Ayatollah Ziaberi). By examining the mobile nature of this Ta'ziyeh, it becomes clear how the mentioned places became narrative and move away from their previous functions and roles so that this cause transforms of places, spaces and also the transcendence of the city during the performance of Ta'ziyeh.


Retroviruses encapsidate their genome as a dimer of homologous RNA molecules noncovalently linked close to their 5' ends. The dimerization initiation site (DIS) of human immunodeficiency virus type 1 (HIV-1) RNA is a hairpin structure that contains in the loop a 6-nt self-complementary sequence flanked by two 5' and one 3' purines. The self-complementary sequence, as well as the flanking purines, are crucial for dimerization of HIV-1 RNA, which is mediated by formation of a "kissing-loop" complex between the DIS of each monomer. Here, we used chemical modification interference, lead-induced cleavage, and three-dimensional modeling to compare dimerization of subtype A and B HIV-1 RNAs. The DIS loop sequences of these RNAs are AGGUGCACA and AAGCGCGCA, respectively. In both RNAs, ethylation of most but not all phosphate groups in the loop and methylation of the N7 position of the G residues in the self-complementary sequence inhibited dimerization. These results demonstrate that small perturbations of the loop structure are detrimental to dimerization. Conversely, methylation of the N1 position of the first and last As in the loop were neutral or enhanced dimerization, a result consistent with these residues forming a noncanonical sheared base pair. Phosphorothioate interference, lead-induced cleavage, and Brownian-dynamics simulation revealed an unexpected difference in the dimerization mechanism of these RNAs. Unlike subtype B, subtype A requires binding of a divalent cation in the loop to promote RNA dimerization. This difference should be taken into consideration in the design of antidimerization molecules aimed at inhibiting HIV-1 replication.


On the basis of their own experience and literature concerning liquidation of the disaster consequences the authors analyse limitations in the disaster health care system. The article shows the trends towards the improvement of medical aid during catastrophes of peaceful period, taking into account various aspects of military doctrine and, especially, the casualty care staging system. It is stressed that the disaster health care procedures will depend on the structure of sanitary losses, characteristic features of the scene of an accident and the dynamics of medical environment. Language: ru


Recent endeavours have enabled the integration of trained machine learning models like Random Forests in resource-constrained programmable switches for line rate inference. In this work, we first show how packet-level information can be used to classify individual packets in production-level hardware with very low latency. We then demonstrate how the newly proposed Flowrest framework improves classification performance relative to the packet-level approach by exploiting flow-level statistics to instead classify traffic flows entirely within the switch without considerably increasing latency. We conduct experiments using measurement data in a real-world testbed with an Intel Tofino switch and shed light on how Flowrest achieves an F1-score of 99% in a service classification use case, outperforming its packet-level counterpart by 8%.


Focusing on youth camp development in Germany and the United States during the interwar period, this article argues not only that such camps played a crucial role in the ways in which national societies dealt with their youth, but also that their history forces us to rethink relations between place-making, nationhood, and modern governing. First, the article addresses the historiography of youth movements in relation to current debates about spatiality, nationalism, and governmentality. The main part of the article examines organized camps, in particular by the German Bünde, the Hitlerjugend (Hitler Youth), and the American Boy Scouts, focusing on their transition from relatively spontaneous activities of particular social movements, to objects of professional design, national-scale planning and intricate management in the interwar period. This development demonstrates how in the seemingly trivial activity of camping, nationalism is interwoven with the project of conducting youth through contact with nature. Despite divergent contexts and political ideologies, youth camp development in this period constituted a set of practices in which the natural environment was deployed to improve the nation's youth, and to eventually reproduce them as governable subjects.


The main objective of this paper is to perform a theoretical analysis of the main issues related to the concept of flow, starting from the stage of knowing in the company's treasury and continuing treasury structures and components classified and recognized in the accounts. We begin this research with a conceptual analysis of enterprise treasury domain definitions, interpretations, approaches, nuances, linguistic indices are sometimes useful, but can be misleading since scientists borrow words from the pool of words. There is the danger of getting contaminated by common understandings and meanings related to everyday, common sense. Analyzing the view of some reputable researchers, and academic elite Romanian definitions over time, we see that the treasury was distinctly defined. All these contradictions are based on our approach to the problem of how to combine the creative rational thinking. It is often said that a problem well put is half solved. Lucian Blaga "a problem not only never made ... objective data can be called only objective data to which we refer, in that they are outside the problem started, and in that matter absorbs as a receptacle theirs. All of these objective data we call the problem area. "(Black, 1974).


Although it has been suggested that about 2.5% of the population as a whole should
be regarded as having a mild-to-moderate learning disability, only about 0.25% of
the population is registered as having a learning disability. This paper considers
why this disparity exists. It is suggested that although 2.5% of the population may be
a good estimate for people with IQs less than 70, a better estimate of the proportion
of the population who reach a dual criteria of having both a low IQ and social/skill
defects is about 1%. It is pointed out that even if true prevalence rate of learning
disability is nearer to 1% rather than 2.5%, services still only know of a small
proportion of people who could be considered to have a learning disability, and
there are probably a large number of people with unidentified learning disabilities. It
is also noted that the term 'learning disability' can be very confusing as it is not clear
if it refers to people who have IQs below 70, people with both intellectual and
adaptive disabilities or people who have been given a learning disability label. The
implications of this for services and research are discussed.


Background Restless legs syndrome (RLS) is a sensorimotor neurological disorder characterized by an irresistible urge to move the legs. It has been reported that RLS patients show cognitive deficits, presumably due to hyperactivity causing loss of attention, or malfunctions in the frontal region resulting from sleep deprivation. However, the mechanism underlying cognitive deficits in RLS patients is mostly unknown. As an effort to clarifying this, we investigated the differences in neural activity and phase synchrony between healthy controls and RLS patients during cognitive task performances. Methodology/Principal Findings Seventeen female drug-naive RLS patients were enrolled in the study, and an age-matched group of thirteen healthy female volunteers served as controls. Multichannel event-related potentials (ERPs) were recorded from RLS patients and normal controls while performing a visual oddball task. In addition to conventional analyses of ERP waveforms and spectra, interregional gamma-band phase synchrony (GBPS) was investigated to observe the differences in interregional neural synchronies between normal and RLS patient groups. Strong GBPS was observed primarily between anterior and posterior regions along the midline for both groups. Along with significant reduction and delay of P300 ERP and induced gamma-band activity (GBA), the GBPS was considerably decreased in RLS patients compared to normal subjects, especially at frontal region. Conclusions Overall, our results support that cognitive dysfunction in RLS patients is associated with reduced interregional neural synchrony as well as alterations in local neural activity.


The aim of the study was to translate and evaluate the psychometric evidence of the Spanish version of the COVID-19 impact scale in the general population of Peru, to measure psychological stress responses produced by the COVID-19 pandemic, including emotional responses and difficulty in performing activities of daily living. Participants were 601 Peruvians, who responded to an online survey consisting of questions designed to collect sociodemographic data, the CIS and the fear of COVID-19 scale. The forward and backward translation method was used to translate the English version into Spanish. A confirmatory factor analysis (CFA), graded response model was used to estimate the discrimination (a) and difficulty (b) parameters of the items. Multi-group CFA was used to assess measurement invariance. Regarding validity based on the validity in relation to other variables, an explanatory model was proposed using the SEM path method. The unidimensional structure of the 10-item CIS was not confirmed. Therefore, it was suggested that a six-item model of the CIS (CIS-6) provides a better fit and reliable score. The multigroup CFA showed that the CIS-6 does not exhibit measurement invariance between males and females. In addition, the CIS-6 items present adequate discrimination and difficulty indices. A higher presence of the latent trait (in this case, perception of the impact of COVID-19) is required to answer the higher response categories. The findings would help to assess those individuals more prone to the impact of the COVID-19 pandemic and to have evidence for the development of interventions aimed at decreasing the impact.


The complexity of the jugular foramen can be appreciated once its deep location, variability in shape and size, and neurovascular contents are recognized. Safe surgical access to this foramen is hindered by surrounding structures. Structures that traverse the jugular foramen are the sigmoid sinus, inferior petrosal sinus, jugular bulb, glossopharyngeal nerve, vagus nerve, accessory nerve, Jacobson's nerve, Arnold's nerve, meningeal branches of the ascending pharyngeal and occipital arteries, and the cochlear aqueduct. The classic description of the jugular foramen divides this structure into two discrete compartments, the pars nervosa and the pars venosa. However, microanatomical studies have demonstrated that this compartmentalization of the jugular foramen is an oversimplification and has no surgical significance. Instead, it is more useful to describe the petrosal, sigmoid, and intrajugular portions of the jugular foramen. The petrosal portion contains the inferior petrosal sinus. The sigmoid portion receives the sigmoid sinus. The intrajugular portion contains cranial nerves IX, X, and XI. All of the surgical approaches to this region require thorough knowledge of the temporal bone, which forms the lateral, posterior, and superior boundaries of the jugular foramen.


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Prehabilitation is the process of enhancing preoperative functional capacity to improve tolerance for the upcoming stressor; it was associated with improved postoperative outcomes in a handful of studies, but never evaluated in transplantation. Kidney transplant (KT) candidates may be uniquely suited for prehabilitation because they experience a profound loss of functional capacity while waiting years on dialysis. To better understand the feasibility and effectiveness of prehabilitation in KT, we conducted a pilot study of center‐based prehabilitation for candidates; this intervention consisted of weekly physical therapy sessions at an outpatient center with at‐home exercises. We enrolled 24 participants; 18 participated in prehabilitation (75% of enrolled; 17% of eligible). 61% were male, 72% were African American, and mean age = 52 (SD = 12.9); 71% of participants had lower‐extremity impairment, and 31% were frail. By 2 months of prehabilitation, participants improved their physical activity by 64% (P = 0.004) based on accelerometry. Participants reported high satisfaction. Among 5 prehabilitation participants who received KT during the study, length of stay was shorter than for age‐, sex‐, and race‐matched control (5 vs 10 days; RR = 0.69; 95% CI:0.50‐0.94; P = 0.02). These pilot study findings suggest that prehabilitation is feasible in pretransplant patients and may potentially be a strategy to improve post‐KT outcomes.


Supernatants from endotoxin-stimulated human leukemic cells and human recombinant interferon-beta 2 similarly enhance synthesis of alpha 1-antichymotrypsin and haptoglobin but suppress synthesis of albumin in cultured Hep G2 cells. Human recombinant tumor necrosis factor only slightly affects production of alpha 1-antichymotrypsin and albumin in a similar manner as leukocyte cytokines. In distinction, recombinant human interferon-gamma profoundly inhibits synthesis of alpha 1-antichymotrypsin, and especially of haptoglobin, but stimulates production of alpha 2-macroglobulin thus modulating the acute phase response of these cells.


It is well known that vibration of contact interfaces is the main cause of contact degradation by the so called fretting corrosion phenomenon. In fact the process of generating particles by mechanical wear produces an increase of contact voltage, frequently manifested by a high contact resistance in low power and signal connectors. In high power connectors, this degradation is expected to be accentuated by thermal effects generated by increasing the contact voltage up to melting and arcing voltages. The main objective of this work is to examine conjointly the electrical behavior and amount of wear of a connector terminal under vibration and higher current stress. In order to reproduce harsh vibration conditions, spring with lamella shape from an automotive connector, made from a copper alloy and coated with 2 mum of tin, are submitted to a high number of oscillations (103 to 106) where the pin is firmly attached to a fixed support. High frequency oscillations (100 Hz) with an amplitude of 50 mum is used. The contact is inserted into a resistive circuit supplied by 20 V and 3 A. The contact voltage is measured with a fast sampling oscilloscope and the voltage histogram is built up in real time. The losses of mass in the erosion track are evaluated by micro weighing. The main results show that at the low level of wear observed during the earlier stage of fretting, the contact voltage corresponds to pure constriction voltage < 20 mV. However, after this initiation period as the wear is increased, the contact voltage is increased and reaches a few hundred millivolts (melting and fritting voltage). Finally in last stage of degradation, an arcing voltage due to bounce phenomena is detected. These short arcs, observed for the first time in fretting under power, could accentuate the wear and the degradation process by erosion and mass transfer.


Despite its success in the software industry, Software-as-a-Service (SaaS) still struggles with fulfilling customer expectations regarding service quality. To contain customer churn rates to low levels, SaaS providers have to address their service quality weak spots and find out which factors are crucial for continued SaaS usage. Drawing on previous service quality literature, we develop a Zone-of-Tolerance (ZOT)-based SaaS-QUAL scale and validate it in a model of IS continuance based on two empirical surveys of SaaS using firms. By doing this, we examine the importance of SaaS service quality factors for shaping customer satisfaction and SaaS continuance intentions. Furthermore, we provide insights into what service factors effectively meet or miss SaaS customer expectations. As a practical contribution, we develop and apply a SaaS-QUAL scale that can be used as a diagnostic tool by SaaS providers and users alike. For researchers, we enrich existing research models on IS continuance by integrating a more fine-grained conceptualization of service quality confirmation that provides stronger explanatory power than in previous models.


Nowadays, security is becoming a real need for society and a real challenge for those everyday activities such as access control, cash terminals, public transport, Internet... where user authentication is required prior to giving access to confidential information, relevant places or restricted resources. The implementation of a reliable personal recognition system not based on vulnerable topics such as physical keys or passwords is required. Biometrics-based authentication techniques (e.g. face, iris, fingerprint recognition...) in conjunction with smart cards technologies bring a challenging solution to this need. This paper describes the hardware-software co-design of a fingerprint match on card system responsible for matching two fingerprint minutiae sets in a reliable and secure way. The proposed system architecture is composed by a general-purpose 8-bit microcontroller and a 40-kgates FPGA, all embedded in a system on chip device. A good solution is detailed from a performance versus cost point-of-view


A vast economics literature embraces taxation of the carbon content of fossil fuels as the superior policy approach for reducing greenhouse gas emissions and pursuing other major energy policy goals. However, national government experience around the world suggests that carbon taxes face exceedingly difficult political hurdles. Federal experience in the United States and Canada confirms this pattern. This paper reviews sub-federal policy development among American states and Canadian provinces, a great many of whom have been active in climate policy development. With one notable exception, it concludes that explicit carbon taxation appears to remain a political non-starter. At the same time, states and provinces have been placing indirect carbon prices on fossil fuel use through a wide range of policies over the past fifteen years. These tend to strategically alter labeling, finding different ways to characterize new or expanded policies by avoiding the terms of "tax" and "carbon" in imposing costs. The paper offers a framework for considering such a diverse set of strategies and examines common design features, including direct linkage between cost imposition and fund usage to build political support.


This thesis focuses on fatigue analysis and testing of large, multi MW wind turbine blades. The blades are one of the most expensive components of a wind turbine, and their mass has cost implications for the hub, nacelle, tower and foundations of the turbine so it is important that they are not unnecessarily strong. Fatigue is often an important design driver, but fatigue of composites is poorly understood and so large safety factors are often applied to the loads. This has implications for the weight of the blade.
Full scale fatigue testing of blades is required by the design standards, and provides manufacturers with confidence that the blade will be able to survive its service life. This testing is usually performed by resonating the blade in the flapwise and edgewise directions separately, but in service these two loads occur at the same time. A fatigue testing method developed at Narec (the National Renewable Energy Centre) in the UK in which the flapwise and edgewise directions are excited simultaneously has been evaluated by comparing the Palmgren-Miner damage sum around the blade cross section after testing with the damage distribution caused by the service life.
A method to obtain the resonant test configuration that will result in the optimum mode shapes for the flapwise and edgewise directions was then developed, and simulation software was designed to allow the blade test to be simulated so that realistic comparisons between the damage distributions after different test types could be obtained.
During the course of this work the shortcomings with conventional fatigue analysis methods became apparent, and a novel method of fatigue analysis based on multi-continuum theory and the kinetic theory of fracture was developed. This method was benchmarked using physical test data from the OPTIDAT database and was applied to the analysis of a complete blade. A full scale fatigue test method based on this new analysis approach is also discussed.


By the Early Holocene (10,000 to 8,000 B.P.), small wandering bands of Archaic hunter-gatherers began to annually follow the same hunting trails, basing their temporary camps on seasonal conditions and the presence of food. The Pleistocene glaciers had receded by this time, making food more plentiful in some areas and living conditions less hazardous. Although these Archaic peoples have long been known from their primary activities as hunters and gatherers of wild food resources, recent evidence has been found that indicates they also began rudimentary cultivation sometime during the Middle Holocene.Richard Jefferies - an Archaic specialist - comprehensively addresses the approximately 7,000 years of the prehistory of eastern North America, termed the Archaic Period by archaeologists. Jefferies centers his research on a 380-mile section of the Lower Ohio River Valley, an area rife with both temporary and long-term Archaic sites. He covers the duration of the Holocene and provides a compendium of knowledge of the era, including innovative research strategies and results. Presenting these data from a cultural-ecological perspective emphasizing the relationships between hunter-gatherers and the environments in which they lived, Jefferies integrates current research strategies with emerging theories that are beginning to look at culture history in creative ways.


ABSTRACT Stochastic upwelling of seawater in the Baltic Sea from the deep, anoxic bottoms may bring low-pH water rich in CO2 close to the surface. Such events may become more frequent with climate change and ongoing ocean acidification (OA). Photoautotrophs, such as macroalgae, which are important foundation species, have been proposed to benefit from increased carbon availability due to reduced energetic cost in carbon acquisition. However, the exact effects of CO2 fertilization may depend on the ambient light environment, as photosynthesis rates depend on available irradiance. In this experimental study, interacting effects of CO2 addition and irradiance on the habitat-forming macroalga Fucus vesiculosus were investigated during two seasons – winter and summer – in the northern Baltic Sea. Growth rates remained unaffected by CO2 or irradiance during both seasons, suggesting that direct effects of elevated CO2 on mature F. vesiculosus are small. Increases in CO2 affected algal elemental ratios by increasing carbon and decreasing nitrogen content, with resulting changes in the C:N ratio, but only in winter. In summer, chlorophyll a content increased under low irradiance. Increases in CO2 caused a decline in light-harvesting efficiency (decrease in Fv/Fm and α) under high irradiance in summer, and conversely increased α under low irradiance. High irradiance caused increases in the maximum relative electron transport rate (rETRmax) in summer, but not in winter. Differences between winter and summer indicate that F. vesiculosus responses to CO2 and irradiance are season-specific. Increases in carbon content during winter could indicate slightly positive effects of CO2 addition in the long run if the extra carbon gained may be capitalized in growth. The results of this study suggest that increases in CO2, either through upwelling or OA, may have positive effects on F. vesiculosus, but these effects are probably small.


To the Editor.— The published list of some 400 Canadian food additives 1 contains many chemical compounds known to dermatology. For example, preservatives such as parabens, which are present in some of our topically used therapeutic creams may also be added to foods. Methyl and propyl paraben may be added in the amount of 1,000 ppm to tomato pulp, puree, paste, and catsup, to pickles and relishes, fruit juices, jam, marmalade, fruit jelly, mincemeat, packaged fish, meat, and poultry. Sorbic acid, sorbates, ethylenediamine, sodium benzoate, and benzoic acid (1,000 ppm) are also permitted as preservatives for foods as well as for therapeutic creams. Potassium and ammonium persulphate and benzoyl peroxide, which are known to be sensitizers for the skin, may be used for flour. Waxes and gums which include some known skin sensitizers, namely, guaiac, guar, karaya, acacia, tragacanth, benzoin, spermaceti, carnauba, and beeswax figure in the list, the last


Objectives: Intra-articular (IA) anesthetic injection is commonly performed as a diagnostic test in the setting of femoroacetabular impingement (FAI). Currently, there is a paucity of data correlating post-injection pain relief and outcomes after hip arthroscopy for FAI. The purpose of this study is to determine whether the amount of pain relief after IA injection predicts clinical and functional outcomes following hip arthroscopy. We hypothesize that increased pain relief (>50%) will correlate with better outcomes after surgery. Methods: The records of patients undergoing hip arthroscopy for FAI at our institution between April 2007 and April 2012 were reviewed. We identified patients who underwent IA injection and subsequent hip arthroscopy. Inclusion criteria were: ultrasound or fluoroscopic guided intra-articular anesthetic injection performed at our institution, prospectively documented pre- and post-injection Numerical Rating Scale (NRS) pain scores, no prior ipsilateral hip surgery, and minimum 1 year follow-up. Pre-operative radiographs were reviewed and degree of osteoarthritis was determined using the Tonnis classification system. Outcomes were assessed with Modified Harris Hip Score (MHHS) and Hip Outcome Score (HOS). Univariate and multivariate models were performed to assess whether percent pain relief correlated with outcome scores. Results: 99 hips in 96 patients met our inclusion criteria and included 71 females (74%) and 25 males (26%) with a mean age of 37.5 ± 14.0 years. 26 patients had Tonnis grade 0, 55 had grade 1, and 18 had grade 2 (0 grade 3). Mean pain relief after IA injection was 73.6 ± 36.1 (range 0-100) percent. 26 patients (26%) had ≤50% pain relief while 73 (74%) had >50% pain relief. Outcome scores were obtained at a mean 14.9 months. Mean MHHS, HOS-ADL, and HOS-Sport scores were 79.2 ± 17.3, 82.6 ± 17.3, and 67.4 ± 28.2, respectively. There was no statistical correlation between percent pain relief and MHHS, HOS-ADL, or HOS-Sport scores. There was no significant difference in outcome scores between those with ≤50% and >50% pain relief. While patients that received >50% pain relief by IA injection were more likely to achieve positive results (MHHS >70) with a likelihood ratio of 1.23 (95% CI 0.92-1.53), this was not significant. Multivariate regression analysis demonstrated no significant predictors of outcome, including age, gender, Tonnis grade, percent relief with IA injection, number of months postoperatively, or type of surgery. Conclusion: In patients undergoing hip arthroscopy for FAI, our data indicates that the amount of pain relief from IA injection is a poor predictor of short term outcome, even when adjusting for chondral degeneration. While anesthetic injections can be an important diagnostic tool in select patients, correlation of the clinical history, physical examination, and imaging findings are fundamental. In addition, outcome following hip arthroscopy remains multifactorial.


There is a class of signal processing algorithms that achieves gain by exploiting the amplitude fluctuations in the spectrum analyzed acoustic power. One of those processors is presented. The causes of fluctuations that influence the performance of such processors are discussed, and processed results from a fluctuation-based processor are presented. Gains relative to the average power processor in signal-to-noise ratio (SNR) of as much as 10 dB, and gains in spatial and spectral resolution, minimum detectable levels, and other measures of processor performance have been achieved. For the most part, the additional gains from exploiting fluctuations are independent of the frequency resolution and the array aperture (or number of elements if the noise is "white") and depend on the number of averages and percent of overlap of consecutive time-to frequency fast Fourier transforms (FFT).


Based on indications that hand dominance is characterized by asymmetrical interlimb coupling strength (with the dominant hand exerting stronger influences on the nondominant hand than vice versa), intentional switches between rhythmic bimanual coordination patterns were predicted to be mediated primarily by phase adaptations in the movements of the nondominant hand. This hypothesis was supported for both right-handed and left-handed participants who performed voluntary switches from in-phase to antiphase coordination and vice versa, at four different frequencies. In accordance with previous indications that handedness is expressed less consistently in left-handers, the asymmetry between the hands was less pronounced in left-handed than in right-handed participants. The asymmetry was smaller for switches from in-phase to antiphase coordination (i.e., in the direction opposite to spontaneous transitions) than for switches in the reverse direction, suggesting that (the expression of) the handedness-related asymmetry in coupling strength was weakened by intentional processes associated with these switches.


In this article we illustrate important characteristics of the diffraction of cold atoms from periodic light potentials generated from coupling a light wave to dielectric nanostructures. We apply a recently developed theoretical approach to investigate the behavior of Cs atoms dropped onto a periodically modulated optical dipole potential where the period of the modulation is controlled by the periodicity of the dielectric array. These nanostructures take the form of one-dimensional line gratings or two-dimensional point gratings. We discuss several important parameters critical to the successful realisation of laboratory experiments and future atom-optical instrumentation using this new kind of atomic diffraction medium.


Abstract Analysis of a six parent diallel cross involving high and low nitrogen fixing peanut (Arachis hypogaea L.) genotypes revealed the predominant nature of non-additive genetic variance for nitrogenase activity and other traits. Germplasm line, NC Ac 2821 had the highest general combining ability for nitrogenase activity, total nitrogen, leaf area, and top weight, and therefore, it should be a good parent for use in breeding programs. Nitrogenase activity was significantly and positively correlated with nodule number, nodule mass, total nitrogen, top weight, and root weight. This evidence suggests the possibility of breeding for increased nitrogen fixation and thus yield in peanut.


AbstractThis paper reviews the literature on the diffusion and popularity of vague management ideas. Is it the vagueness in itself that makes them so popular, or are there other explanations? Five possible explanations for the attraction of ambiguous management ideas are suggested: (i) concretising; (ii) symbolic legitimisation; (iii) seduction; (iv) unknown use; and (v) challenge. Some of the explanations are explicitly suggested in the literature, whereas others are explanations offered by the present author on the basis of a review of the literature. The five explanations are categorised according to the level of consciousness of the use of vague ideas among the users, and according to whether the ideas are implemented in actual practice or used only in talk. The present paper also discusses what management researchers could do to help those who use vague management ideas.


This study investigates the neural pathways, mediators, and cyclooxygenase isoenzymes involved in the gastroprotection conferred by peptone in rats. Intragastric perfusion with 8% peptone protected against gross and histological damage induced by subsequent perfusion with 50% ethanol. The gastroprotective effect of peptone was near maximally inhibited by gastrin immunoneutralization, inactivation of capsaicin-sensitive afferent neurons, calcitonin gene-related peptide (CGRP) immunoneutralization, blockade of gastrin receptors, CGRP, bombesin/gastrin-releasing peptide (GRP), or somatostatin receptors, and by the nitric oxide (NO) synthase inhibitor NG-nitro-L-arginine methyl ester and was partially (46%) counteracted by atropine. Indomethacin and the selective cyclooxygenase-2 inhibitors NS-398 and L-745,337 dose dependently (50% inhibitory dose, 4.2, 0.8, and 1.5 mg/kg, respectively) attenuated the peptone-induced protection. Dexamethasone was ineffective. These results indicate that protective effects of peptone involve endogenous gastrin and possibly somatostatin and are mediated by capsaicin-sensitive afferent, cholinergic, and bombesin/GRP neurons. CGRP, NO, and prostaglandins participate as essential mediators. The study provides evidence that prostaglandins derived from a constitutive cyclooxygenase-2 contribute to mucosal defense in the presence of ulcerogens and thus participate in homeostatic functions of the stomach.


Congenital malformations are developmental disorders that arise before birth during the embryonic (2nd 8th week of development) or fetal period (9th 38th week of development) (from the Latin congenitus = "born with"). The cause may be genetic or contingent on external influences. The rate of incidence for children born alive is approximately 3%. Toxic agents that may cause embryonic damage and malformations are called teratogens, and the study of the cause and characteristics of inherent malformations is called teratology (Gr. teras = monstrosity, marvel). Infections such as rubella, medications like thalidomide, drugs such as alcohol and tobacco, or radiation are all teratogens.


Pre-training Reinforcement Learning (RL) agents in a task-agnostic manner has shown promising results. However, previous works still struggle to learn and discover meaningful skills in high-dimensional state-spaces. We approach the problem by leveraging unsupervised skill discovery and self-supervised learning of state representations. In our work, we learn a compact latent representation by making use of variational or contrastive techniques. We demonstrate that both allow learning a set of basic navigation skills by maximizing an information theoretic objective. We assess our method in Minecraft 3D maps with different complexities. Our results show that representations and conditioned policies learned from pixels are enough for toy examples, but do not scale to realistic and complex maps. We also explore alternative rewards and input observations to overcome these limitations. The code is publicly available at https://github.com/juanjo3ns/mineRL.


Our previous observation on immune modulation induced by a given factor VIII (F VIII) concentrate preparation was extended by showing that the immune-modulating capacity is a more general feature of F VIII products and is independent of product purity. Interaction of human monocytes with therapeutic concentrations of various F VIII concentrates (0.2 to 2 IU F VIII/mL, six different F VIII concentrates from four manufacturers) led to a significant reduction in the expression of IgG Fc receptors in the membrane of these cells (F VIII concentrate-induced downmodulation of the receptor). This Fc receptor downmodulation was achieved by a short (1-hour) incubation of human monocytes with F VIII concentrates 16 hours prior to the Fc receptor assay and did not correlate with the respective product's IgG content. Although the IgG concentrations of the different products varied greatly (from 1.0 to 177.3 mg/1,000 IU F VIII), all products behaved comparably with respect to Fc receptor downmodulation (F VIII-treated monocytes: 34% +/- 7% to 44% +/- 4% rosette-forming cells; controls in the absence of F VIII: 83% +/- 5%). Furthermore, we also were able to demonstrate that heat treatment of F VIII, now used by virtually every manufacturer to eliminate contaminating viruses, had no effect on the respective products' Fc receptor-modulating capacity. The immune-modulating component was characterized as being a high-molecular-range compound containing IgG, IgM, F VIII, and blood group substances (most likely a combination of immune complexes and immunoglobulin aggregates). This compound is present in comparable amounts in both high-purity and intermediate-purity products and apparently copurifies with F VIII during the manufacturing process.


1. Elastins purified by various methods from the ligamentum nuchae and the lungs of cattle of various ages were analysed for amino acid compositions and lysine-derived cross-links. 2. In fully mature elastins from adults the main cross-links were desmosine, isodesmosine and lysinonorleucine and the so-called aldol-condensation product. Trace amounts of merodesmosine were also found. 3. During the normal maturation of elastins the amounts of desmosine, isodesmosine and lysinonorleucine increased, whereas the aldol-condensation product and intact lysine residues decreased and merodesmosine remained the same. 4. Elastins from young animals contained significant amounts of dehydromerodesmosine whereas elastins from adults contained virtually nil. Evidence is presented which suggests that the biosynthetic pathway of desmosine and isodesmosine proceeds via the aldol-condensation product and dehydromerodesmosine.


The purpose of this paper is to propose a general precision allocation method to improve
machining performance of CNC machine tools based on certain design requirements. A
comprehensive error model of machine tools is established by using the differential motion
relation of coordinate frames. Based on the comprehensive error model, a reliability model
is established by updating the primary reliability with an advanced importance sampling
method, which is used to predict the machining accuracy reliability of machine tools. Besides, to identify and optimize geometric error parameters which have a great influence on machining accuracy reliability of machine tools, the sensitivity analysis of machining accuracy is carried out by improved first-order second-moment method. Taking a large CNC gantry guide rail grinder as an example, the optimization results show that the method is effective and can realize reliability optimization of machining accuracy.


Objective To evaluate the effect of initial low energy permissive underfeeding ("trophic feeding") versus full energy enteral feeding ("full feeding") on physical function and secondary outcomes in patients with acute lung injury. Design Prospective longitudinal follow-up evaluation of the NHLBI ARDS Clinical Trials Network's EDEN trial Setting 41hospitals in the United States. Participants 525 patients with acute lung injury. Interventions Randomised assignment to trophic or full feeding for up to six days; thereafter, all patients still receiving mechanical ventilation received full feeding. Measurements Blinded assessment of the age and sex adjusted physical function domain of the SF-36 instrument at 12 months after acute lung injury. Secondary outcome measures included survival; physical, psychological, and cognitive functioning; quality of life; and employment status at six and 12 months. Results After acute lung injury, patients had substantial physical, psychological, and cognitive impairments, reduced quality of life, and impaired return to work. Initial trophic versus full feeding did not affect mean SF-36 physical function at 12 months (55 (SD 33) v 55 (31), P=0.54), survival to 12 months (65% v 63%, P=0.63), or nearly all of the secondary outcomes. Conclusion In survivors of acute lung injury, there was no difference in physical function, survival, or multiple secondary outcomes at 6 and 12 month follow-up after initial trophic or full enteral feeding. Trial Registration NCT No 00719446


Present-day experiments have started to couple traditional simulations of ultracold atom experiments with quantum light-fields in cavities. This has provided a wealth of op- portunities to enlarge the number of interaction potentials: cavity mediated long-range interactions compete with kinetic energies, longitudinal fields, short-ranged collisional or magnetic spin-spin interactions. The intracavity many-body lattice models often have to be maintained far from equilibrium through the presence of external driving lasers that help to boost and engineer the various interaction potentials. The steady influx of energy is compensated by a steady stream of energy out of the atom-cavity system for example by photon losses or atomic spontaneous emission. Several experiments have demonstrated that such environments can give rise to new competing quantum phases.
But this long-standing ambition to push for models with tailorable interaction potentials can bring with it also considerable challenges in their theoretical description, since sponta- neous symmetry breaking transitions in many body lattice systems coupled to dynamical light-fields with single-photon character occur in the presence of drive and dissipation for the photonic force carriers. This clearly calls for model systems where the above men- tioned interplay of interactions, drive, dissipation and cooperative many-body behaviour can be theoretically studied to provide simple, experimentally verifiable predictions.
The Dicke model is, through its simplicity (an exactly solved ferromagnet with infinite range atom-atom interactions mediated by a single cavity mode), an exceptionally well- suited candidate. As the generic model for atom-light interactions, it has been experimen- tally realized in a variety of modern quantum optical systems, highlighting its relevance for present-day research. The Dicke model is also highly versatile itself. It has been extended into the dissipative realm, was promoted to account for multiple optical light modes and was used to describe multiple, coupled single-mode cavity structures. It was adapted to treat spin-selective coupling to a cavity to describe superradiance phase tran- sitions in multi-level atomic systems. Moreover, it was realised in electronic circuits where the dipole coupling of real atoms to single mode fields is replaced by a capacitive cou- pling of artificial atoms to a resonator mode. This illustrates that the Dicke model and its extended variants are 'future-proof' and continue to be of relevance for fundamental light-matter interactions and for driven-dissipative phase transitions.
In this thesis, we investigate magnetic phase transitions in driven-dissipative atomic en- sembles interacting with quantum light. We present three research projects on variants of cooperative radiation of an ensemble of laser driven two-level atoms in a single mode optical cavity, as described by the Dicke model.
Throughout the chapters 2,3 and 4 that contain the main body of research of this thesis, we investigate phase transitions between non-equilibrium stationary states in engineered quantum-optical systems each of which extends the conventional Dicke model physics. As a starting point, we map the quantum equations of motion onto a set of semiclassical nonlinear stochastic equations and analyse their stationary states and instabilities with master equations for atomic spin and photon mean-field amplitudes. These are used to obtain experimentally relevant parameters such as critical atom-light couplings for phase transitions, phase diagrams and properties of stationary non-equilibrium states in addition to cavity output spectra that identify the imprint of magnetic correlations in the light-field.
In chapter 2, we help resolve a discrepancy between earlier experimental investigations of the critical atom-light coupling strength for the superradiance transition in the Dicke model: higher external pumping strengths than theoretically predicted were needed to observe a coherent, superradiant state of the light field in an optical cavity. By including incoherent spontaneous emission of atomic excitations, we extend the dissipative Dicke model to a two loss channel variant containing both photon leakage and atomic decay that reproduces the experimentally observed critical atom-light coupling.
Recent experiments have started to interface quantum many body lattice models with coherent cavity fields, thereby allowing to realize new quantum phases through competing atom-cavity and atom-atom interactions. In chapter 3, we consider a simplified model for such a set-up where a single quantized mode of the light-field interacts with an ensemble of Rydberg-dressed atoms inside a high finesse optical cavity. This model provides a base case for further studies of quantum magnets in optical cavities. At the heart of this model is a competition of short- (dipolar atom-atom) and long-range (atom-light) interactions at the Hamiltonian level in the presence of both spontaneous emission and photon leak- age through the cavity mirrors. We show that different magnetic phases can coexist with coherent atomic radiation and provide clear experimental signatures to identify the mag- netic structure and intra-cavity dynamics. We suggest an experimental level-scheme for a quantum optical implementation of our model.
In chapter 4 we consider a generic, collective decay for many-body excitations in the paradigmatic Dicke model. This extension drastically enriches the dynamics as it induces a bicritical point and a bistable regime dominated by true non-equilibrium fluctuations that induce a dissipative first-order phase transition that can only be resolved by including finite fluctuation corrections with the help of stochastic Langevin equations. We investigate the hysteretic response to time-dependent ramps of the atom-light coupling. Discontinuous first-order phase transitions where metastable states coexist in a hysteresis domain have been investigated in recent dissipative quantum-optical experiments. We review noise- activation far from thermal equilibrium in chapter 5.