bluuebunny/crossref_metadata_2025_split huggingface dataset:
Capsule Structural Heterogeneity and Antigenic Variation in
Cryptococcus neoformans
Authors: McFadden Diane C. , Fries Bettina C. , Wang Fang , Casadevall Arturo 
Published: June 2007

ABSTRACT

Cryptococcus neoformans
is a human pathogenic fungus with a capsule composed primarily of glucuronoxylomannan (GXM) that is important for virulence. Current views of GXM structure postulate a polymer composed of repeating mannose trisaccharide motifs bearing a single β(1,2) glucuronic acid with variable xylose and
O
-acetyl substitutions to form six triads. GXM from different strains is notoriously variable in triad composition, but it is not known if the polymer consists of one or more motif-repeating units. We investigated the polymeric organization of GXM by using mass spectrometry to determine if its compositional motif arrangement was similar to that of bacterial capsular polysaccharides, namely, a polymer of a single repeating unit. The results were consistent with, and confirmatory for, the current view that the basic unit of GXM is a repeating mannose trisaccharide motif, but we also found evidence for the copolymerization of different GXM repeating units in one polysaccharide molecule. Analysis of GXM from isogenic phenotypic switch variants suggested structural differences caused by glucuronic acid positional effects, which implied flexibility in the synthetic pathway. Our results suggest that cryptococcal capsule synthesis is fundamentally different from that observed in prokaryotes and employs a unique eukaryotic approach, which theoretically could synthesize an infinite number of structural combinations. The biological significance of this capsule construction scheme is that it is likely to confer a powerful avoidance strategy for interactions with the immune system and phagocytic environmental predators. Consistent with this premise, the antigenic variation of a capsular epitope recognized by a nonprotective antibody was observed under different growth conditions.
DNA Diversification in Two
Sinorhizobium
Species
Authors: Guo Xianwu , Flores Margarita , Morales Lucía , García Delfino , Bustos Patricia , González Víctor , Palacios Rafael , Dávila Guillermo 
Published: June 2007

ABSTRACT

The comparative analysis of genomic characteristics and single-nucleotide polymorphism patterns from large fragments borne on different replicons of
Sinorhizobium
spp. genomes clearly demonstrate that DNA recombination among closely related bacteria is a major event in the diversification of this genome, especially in pSymA, resulting in mosaic structure.
Non-malignant disease mortality in meat workers: a model for studying the role of zoonotic transmissible agents in non-malignant chronic diseases in humans
Authors: Johnson E S , Zhou Y , Sall M , El Faramawi M , Shah N , Christopher A , Lewis N 
Published: June 2007

Background:Current research efforts have mainly concentrated on evaluating the role of substances present in animal food in the aetiology of chronic diseases in humans, with relatively little attention given to evaluating the role of transmissible agents that are also present. Meat workers are exposed to a variety of transmissible agents present in food animals and their products. This study investigates mortality from non-malignant diseases in workers with these exposures.Methods:A cohort mortality study was conducted between 1949 and 1989, of 8520 meat workers in a union in Baltimore, Maryland, who worked in manufacturing plants where animals were killed or processed, and who had high exposures to transmissible agents. Mortality in meat workers was compared with that in a control group of 6081 workers in the same union, and also with the US general population. Risk was estimated by proportional mortality and standardised mortality ratios (SMRs) and relative SMR.Results:A clear excess of mortality from septicaemia, subarachnoid haemorrhage, chronic nephritis, acute and subacute endocarditis, functional diseases of the heart, and decreased risk of mortality from pre-cerebral, cerebral artery stenosis were observed in meat workers when compared to the control group or to the US general population.Conclusions:The authors hypothesise that zoonotic transmissible agents present in food animals and their products may be responsible for the occurrence of some cases of circulatory, neurological and other diseases in meat workers, and possibly in the general population exposed to these agents.
Notch inhibition in Kaposi's sarcoma tumor cells leads to mitotic catastrophe through nuclear factor-κB signaling
Authors: Curry Christine L. , Reed Laura L. , Broude Eugenia , Golde Todd E. , Miele Lucio , Foreman Kimberly E. 
Published: June 2007

Abstract
Kaposi's sarcoma (KS) is the most common neoplasm in untreated AIDS patients and accounts for significant morbidity and mortality worldwide. We have recently reported that Notch signaling (which plays an important role in cell proliferation, apoptosis, and oncogenesis) is constitutively activated in KS tumor cells. Blockade of this activity using γ-secretase inhibitors resulted in apoptosis of SLK cells, a KS tumor cell line; however, this apoptosis was preceded by a prolonged G2-M cell cycle arrest. This result led us to hypothesize that the cells were undergoing mitotic catastrophe, an abnormal mitosis that leads to eventual cell death. Here, we show that Notch inhibition in KS tumor cells using γ-secretase inhibitors or Notch-1 small interfering RNA resulted in G2-M cell cycle arrest and mitotic catastrophe characterized by the presence of micronucleated cells and an increased mitotic index. Interestingly, Notch inhibition led to a sustained increase in nuclear cyclin B1, a novel observation suggesting that Notch signaling can modulate expression of this critical cell cycle protein. Further analysis showed the induction of cyclin B1 was due, at least in part, to increased nuclear factor-κB (NF-κB) activity, which was also required for the G2-M growth arrest after Notch inhibition. Taken together, these studies suggest that Notch inhibition can initiate aberrant mitosis by inducing NF-κB activity that inappropriately increases cyclin B1 resulting in cell death via mitotic catastrophe. [Mol Cancer Ther 2007;6(7):1983–92]
Islamic Insurance: National Features and Legal Regulation
Authors: Bekkin Renat 
Published: June 2007

AbstractThe present paper studies Islamic insurance (takaful) as opposed to conventional one. The first part of the paper covers, among other things, such issues as nature and historic roots of Islamic insurance, early forms of Islamic insurance and narrates the disputes among Muslim scholars concerning the compatibility of insurance with Islamic Shariah. The second part deals with history and emergence of Islamic insurance in the modern financial market, as well as the practice of Islamic insurance in different countries. The third part discusses the feasibility of Islamic insurance in Russia in the current legal framework. The paper contains comprehensive glossary of related terms.
Administrative Contracts and Arbitration, in Light of the Kuwaiti Law of Judicial Arbitration No. 11 of 1995
Authors: Alhamidah Khalifah 
Published: June 2007

AbstractThe state's administration, nowadays, undertakes many tasks due to the movement towards a modern state. This fact results in wide public services that it came to fulfill. Therefore, different legal methods are used in the sake of providing individuals with these services. Aiming at giving private sectors a role in such services, the state's administration relies on contractual relationships with those sectors. Indeed, through this legal method, the public services are provided, and the administration is helped in fulfilling its commitments.Seeking to organise disputes arising from the contractual relationships, the Kuwaiti legislature promulgated the law No. 11 of 1995 establishing the Department of Judicial Arbitration. In Article (2), the law gave the private sectors that entered into a contract in which the stat's administration is a party to resort to judicial arbitration in order to solve their disputes. The Article, also, emphasised that whenever the said sectors chose this method, the administration was obliged to accept the arbitration.This study came to highlight the elements of the said law, discuss the suitability of administrative contracts to be subject to the arbitration and examine the Kuwait courts' trend in relation to this matter.
"And Amicable Settlement Is Best": Sulh and Dispute Resolution in Islamic Law
Authors: Othman Aida 
Published: June 2007

AbstractThe attention accorded to the institution of qadā' 'judgeship' and the adjudicative functions of the qādi has obscured another important method for resolving disputes in Islamic law, namely sulh 'amicable settlement'. While many studies on dispute resolution in Muslim societies have portrayed sulh mainly as a manifestation of customary practice within informal settings, a study of the legal sources reveals that it is not extra-judicial but is rather an integral aspect of an Islamic justice system.Citing authoritative traditions on the potentially disruptive effects of adjudication, jurists instructed disputants and qādis alike to first consider conciliation to solve conflicts. A qādi might opt for sulh in lieu of proceeding to trial, either steering disputants towards settlement on their own, with the assistance of mediators, or mediate the case himself. At the same time, jurists were also concerned with ascertaining the parameters within which sulh should operate, especially when they might offend the rules against ribā (usury) and gharar (uncertainty, deception, or unreasonable risk). The legal debates on sulh during the formative period of Islamic law show how jurists struggled to balance competing ethical and religious ideals: those of conciliation and compromise with those of truth and justice. In some situations, the individual's right to his full legal entitlements should be upheld, and sulh should not be given precedence over the formal, truth-seeking procedures of adjudication.
Semence, vertu formatrice et intellect agent chez Nicolò Leoniceno entre la tradition arabo-latine et la renaissance des commentateurs grecs
Authors: Hirai Hiro 
Published: June 2007

AbstractThe treatise On Formative Power (Venice, 1506) of Ferrara's emblematic medical humanist, Nicolò Leoniceno (1428-1524), is the one of the first embryological monographs of the Renaissance. It shows, at the same time, the continuity of medieval Arabo-Latin tradition and the new elements brought by Renaissance medical humanism, namely through the use of the ancient Greek commentators of Aristotle like Simplicius. Thus this treatise stands at the crossroad of these two currents. The present study analyses the range of Leoniceno's philosophical discussion, determines its exact sources and brings to light premises for the early modern development of the concept of formative force, which will end up in the theory of "plastic nature" at the heart of the Scientific Revolution.
Flow Variability in a North American Downtown Street Canyon
Authors: Klein Petra , Clark James V. 
Published: July 2007

Abstract
Previous field and laboratory studies have indicated that flow and turbulence inside urban areas and, in particular, in street canyons, is very complex and is associated with wakes and vortices developing near buildings. However, a number of open questions still exist, primarily with regard to which parameters determine the structure of street-canyon flow. The paper presents results from high-resolution wind measurements in a downtown urban street canyon in Oklahoma City, Oklahoma, that were conducted during the Joint Urban 2003 tracer experiment. Data collected with sonic anemometers on two towers installed on opposite sites of the street canyon, each with five different measurement levels, have been analyzed, and the variation of in-canyon flow and turbulence parameters with wind direction and atmospheric stability is discussed. It was found that the street-canyon flow is strongly channeled and its direction is determined by the along-canyon component of the above-roof-level winds. As a consequence, the direction of the street-level winds changes abruptly, and small variations of the upwind direction can significantly alter the in-canyon flow properties. Contrary to results from studies with idealized street canyons, the along-canyon flow components remained significant even for conditions with winds approaching the street at almost perpendicular angles. For such wind directions, a tendency toward development of street-canyon vortices with pronounced vertical motions have been found. However, the complex building geometries at the chosen measurement site enhance the complexity of the flow patterns, and situations with a classic street-canyon vortex rotating in the street could not be identified. In addition, the comprehensive dataset from the Joint Urban 2003 field campaign allowed detailed study of the influence of boundary layer stability on flow in the urban canopy layer. It has become clear that very different conclusions can be drawn with regard to these effects depending on the choice of reference values used in the analysis of the street-canyon data. Using winds from higher elevations in the atmospheric boundary layer (250 m) as reference data, one would conclude that atmospheric stability strongly influences in-canyon flow and, in particular, turbulence. However, only minor stability effects are still seen after normalization with wind speed values at average roof-level height (80 m). This choice allows one to conclude that the in-canyon flow is primarily driven by the boundary layer wind field at average roof level.
Manual and Semiautomated Wind Direction Editing for Use in the Generation of Synthetic Aperture Radar Wind Speed Imagery
Authors: Young George S. , Sikora Todd D. , Winstead Nathaniel S. 
Published: July 2007

Abstract
Previous studies have demonstrated that satellite synthetic aperture radar (SAR) can be used as an accurate scatterometer, yielding wind speed fields with subkilometer resolution. This wind speed generation is only possible, however, if a corresponding accurate wind direction field is available. The potential sources of this wind direction information include satellite scatterometers, numerical weather prediction models, and SAR itself through analysis of the spatial patterns caused by boundary layer wind structures. Each of these wind direction sources has shortcomings that can lead to wind speed errors in the SAR-derived field. Manual and semiautomated methods are presented for identifying and correcting numerical weather prediction model wind direction errors. The utility of this approach is demonstrated for a set of cases in which the first-guess wind direction data did not adequately portray the features seen in the SAR imagery. These situations include poorly resolved mesoscale phenomena and misplaced synoptic-scale fronts and cyclones.
Elliptical discontinuities in spherical shells
Authors: Leckie F A , Payne D J , Penny R K 
Published: June 2007

In Part 1 shallow-shell equations expressed in elliptic co-ordinates have been solved in terms of Mathieu functions. Boundary conditions for the rigid insert and for the unreinforced hole are discussed in some detail. Results for an unreinforced opening are compared with experiment and satisfactory agreement is obtained. In Part 2 a parametric study has been made of the factors affecting the stresses at rigid inclusions and at unreinforced holes of elliptical shape in spherical shells. This work makes possible a simple method of representing the results in terms of the stress-concentration factors in flat plates, and a single geometrical variable. The results are verified by experiment. On the basis of this study predictions of the stresses at the intersection of non-radial nozzles in pressure vessels have been made. The theoretical results are compared with experimental evidence already available and reasonable agreement is found.
Fracture criteria for cast iron under biaxial stresses
Authors: Mair W M 
Published: June 2007

Thin-walled cast-iron tubes were stressed to fracture with various combinations of axial tension or compression, and internal or external pressure. The stress components at fracture were estimated, and the fracture locus was compared with theoretical predictions. None of the criteria examined predicts both fracture stress and fracture plane correctly, but Fisher's theory adequately represents the fracture-stress magnitudes for biaxial tension, tension-compression, and biaxial compression. The experimental scatter is such that more elaborate theories are not justified.
Approximate estimation of strain-hardening creep deformation
Authors: Marriott D L 
Published: June 2007

It is demonstrated that creep deformations of a structure based on strain-hardening behaviour are bounded by time-hardening and total-strain solutions. The bounds are not exact, but it is shown that any error is small compared with the difference between the exact solution and the approximate solution when the superposition method (1)∗ is used. As this difference is itself small compared with overall deflections (2) (3), the error due to assuming the strain-hardening solution to be bounded is negligible. It is also shown that strain hardening is asymptotic to the total-strain solution as time increases. A relatively rapid method is suggested for the approximate calculation of deflections, based on an approximate method devised previously (3) for total-strain theory. Numerical examples verify that total-strain theory is a better approximation to strain hardening than is time hardening, especially for large times.
Some theoretical considerations relating to strain concentration in elastic-plastic bending of beams
Authors: Radomski M , White D J 
Published: June 2007

Theoretical derivations are presented for the relations between maximum deflection and the corresponding maximum strain for some simple beams subject to elastic-plastic bending. Both elastic-perfectly plastic and arbitrary stress-strain relations are considered. Where possible, explicit analytical solutions are given, but where this is not possible numerical solutions are obtained by means of computer programmes. The calculations show that in elastic-perfectly plastic material short plastic zones may develop and cause large strains in the beam even though the deflection corresponding to first yield is not greatly exceeded. On the other hand, strain hardening elongates the plastic zones, so producing a more favourable strain distribution along the length of the beam than would exist without it. The more pronounced the strain-hardening characteristic, i.e. the greater the rate of increase of stress with strain, the less concentrated will be the strains. The mode of loading is important in that the higher the rate of change of bending moment, in the region of ihe maximum bending moment, the more concentrated will be the local strains.
A survey of the pathology of marmosets (Callithrix jacchus) under experiment
Authors: Tucker Mary J. 
Published: June 2007

A survey of the pathology of 567 laboratory-bred cotton-eared marmosets ( Callithrix jacchus) is presented. There were few significant pathological changes in animals used in studies up to 6 months in duration, suggesting that the marmoset can be a useful non-human primate species for routine toxicology. The most common pathological changes encountered were chronic colitis, chronic thyroiditis and interstitial mononuclear infiltration in the kidney. No internal parasites were encountered, nor were any viral or bacterial diseases identified. Fungal disease was confined to a few cases of oesophageal mycoses. In a long term study a variety of pathological changes have been observed, including a 'wasting' syndrome, not related to skeletal muscle myopathy, with atrophy of the gastrointestinal tract, salivary glands and gonads, haemosiderosis and fatty change in the liver and osteoporosis. It is suggested that these changes may be related to protein deficiency and that the nutritional requirements of the marmoset require further investigation.
Product Development and Pricing Strategy for Information Goods Under Heterogeneous Outside Opportunities
Authors: Chen Ying-Ju , Seshadri Sridhar 
Published: June 2007

This paper considers a two-stage development problem for information goods with costless quality degradation. In our model, a seller of information goods faces customers that are heterogeneous with regard to both the marginal willingness to pay for quality and the outside opportunity. In the development stage, the seller determines the quality limit of the product. In the second stage, the seller’s problem is to design the price schedule corresponding to different quality levels, taking into account production and distribution costs. We show that versioning is optimal for the seller when customers have multiple outside options or, more generally, convex reservation utilities. In addition, we show that in the optimal solution the seller discards both low-end and high-end customers. Among those that are served, the seller offers a continuum of (inferior) versions to customers with relatively low willingness to pay, and extracts full information rent from each of them. A common version with the quality limit is offered to the rest. We further prove that the seller should offer a single version when reservation utilities are either concave or linear. Through numerical experiments, we study the sensitivity of our results to changes in the cost structure and customer utilities.
Research Note—Comparing IT Workers’ Compensation Across Country Contexts: Demographic, Human Capital, and Institutional Factors
Authors: Levina Natalia , Xin Mingdi 
Published: June 2007

As the IT workforce becomes global, it is increasingly important to understand the factors affecting IT workers’ compensation in labor markets distributed across the globe. Ang et al. (2002) published the first in-depth analysis of compensation for IT professionals juxtaposing human capital endowment (education and experience) and institutional determinants (firm’s size, industry, and sector) of compensation in the Singaporean economy. In this paper, we explore the influence of particular national economies on IT workers’ compensation. We draw on research into the roots of wage differentials in labor economics and build on the Ang et al. research to present a multilevel analysis of IT workers’ compensation in the United States, analyzing the U.S. Bureau of Labor Statistics’ Current Population Survey (CPS) data for 1997, 2001, and 2003. We find that, while institutional differences in Singapore mattered only in conjunction with individual factors, in the U.S. institutional differences had a direct effect on IT workers’ wages. As tightness of IT labor supply decreased in the United States in the early 2000s, the influence of a firm’s size on wages became more pronounced. Also, female IT workers and workers without a college degree fared worse than their male and college-educated counterparts as the IT job market slowed down. We suggest that factors such as presence of job search friction, diversity in the educational system, geographical differences in cost of living, labor mobility, and shortages in IT labor supply vis-à-vis demand help explain the differences among countries. We conclude by outlining the implications of these findings for IT workers, firms, and policy makers.