cssi/SciSciGPT-SciSciNet huggingface dataset:
ADAM10 and Notch1 on murine dendritic cells control the development of type 2 immunity and IgE production.

Background Allergy and allergic asthma are significant health burdens in developed countries and are increasing in prevalence. Dendritic cells (DCs) initiate immune responses to common aeroallergens, and ADAM10 has been demonstrated to be important for the development of adaptive responses. This study's objective was to understand the role of ADAM10 on DCs in the development of allergic and anaphylactic responses. Methods In this study, we used mouse models of allergic airway inflammation (house dust mice and Alternaria alternata) and OVA-induced models of active anaphylaxis to determine the DC-specific function of ADAM10 and Notch signaling. To examine TH1 and TH17 immunity infection with Anaplasma phagocytophilum and Citrobacter rodentium respectively, were used. Results Mice, which have ADAM10 deleted from DCs, have dramatic reductions in IgE production and do not develop significant TH2 immune responses. Further, ADAM10DC−/− mice are resistant to IgE-mediated anaphylaxis. This response is selective for TH2 immunity as TH1 and TH17 immunity is largely unaffected. Notch1, a known ADAM10 substrate, when knocked out of DCs (Notch1DC−/−) demonstrated a similar reduction in anaphylaxis and IgE. Without ADAM10 and Notch1 signaling, DCs were unable to make cytokines that stimulate TH2 cells and cytokines. Anaphylaxis and allergic lung inflammation were restored in ADAM10DC−/− with the overexpression of the Notch1-intracellular domain, confirming the role of Notch signaling. Conclusions Targeting ADAM10 and Notch1 on DCs represent a novel strategy for modulating TH2 immune responses and IgE production.
Bacteria Associated with Larvae and Adults of the Asian Longhorned Beetle (Coleoptera: Cerambycidae)

Abstract Bacteria representing several genera were isolated from integument and alimentary tracts of live Asian longhorned beetle, Anaplophora glabripennis (Motschulsky), larvae and adults. Insects examined were from infested tree branches collected from sites in New York and Illinois. Staphylococcus sciuri (Kloos) was the most common isolate associated with adults, from 13 of 19 examined, whereas members of the Enterobacteriaceae dominated the isolations from larvae. Leclercia adecarboxylata (Leclerc), a putative pathogen of Colorado potato beetle, Leptinotarsa decemlineata (Say), was found in 12 of 37 larvae examined. Several opportunistic human pathogens, including S. xylosus (Schleifer and Kloos), S. intermedius (Hajek), S. hominis (Kloos and Schleifer), Pantoea agglomerans (Ewing and Fife), Serratia proteamaculans (Paine and Stansfield) and Klebsiella oxytoca (Flugge) also were isolated from both larvae and adults. One isolate, found in 1 adult and several larvae, was identified as Tsukamurella incho...
Low Speed, Indraft Wind Tunnels

Since the beginning of time mankind has marvelled and envied the flight of birds. The. literature and artwork of many early civilizations depicted mankind’s keen interest and desire to fly. The ancient Greek tale of Icarus and Daedalus is typical of the folklore dealing with men flying like birds. Through the centuries the invention of kites and hot air balloons kept the interest in flight alive. It would take until the 15th century A.D. before serious scientific study of flight began to develop. One of the first men to study scientifically the flight of birds was Leonardo da Vinci. He drew over 500 sketches and wrote down hundreds of ideas on the concept of manned flight. Much of his work dealt with ornithopters, man powered machines utilizing flapping wings. Many men tried to use da Vinci’s ideas, however, ornithopters proved to be impractical.
Optical and Radio Optical Techniques for Tracking Nocturnal Animals

Abstract Optical and radio optical transmitters permit localization and tracking of nocturnal animals with reliability and precision that cannot otherwise be achieved. Radio tracking seldom offers resolution of better than a wavelength, and use of shorter wavelengths increases problems of absorption and reflection. Visual tracking with night vision scopes is often impossible due to animals' cryptic coloration. This paper describes high efficiency LED flasher circuitry which permits visual localization of subjects in open terrain to 300 m with a night vision scope. Addition of an RF section permits homing to visual range by radio from greater distances or in visually cluttered habitats. Schematics for radio optical transmitters in several frequency bands, some capable of transmitting one or two channels of data, are presented.
Regulators of cell division: endogenous mitotic inhibitors of mammalian cells.

Publisher Summary This chapter deals with the antimitotic substances found in a variety of tissues and sera of humans and animals, as well as with inhibitors produced by cultured cells. It appears that cultured cells release substances which in turn inhibit cell division when the appropriate concentration in the medium is reached. Thus specific and nonspecific inhibitors of cultured cell growth have been reported. Some normal cells appear to produce an inhibitor of the proliferation of oncogenic virus-containing cells which are unable to synthesize a similar antimitotic substance. The growth of normal fibroblasts may be controlled by contact inhibition, protein factors present in the serum added to the medium, and attachment to rigid surfaces (anchorage-depending growth). Extracts from mice and chick embryos have been found to suppress cell growth in vivo andin vitro, respectively. The administration of mouse embryonic and placental extracts inhibited the growth of 70% of spontaneous and transplanted tumors. Since the treatment was mainly effective on carcinomas and not on sarcomas, the extract appeared to have some tissue specificity. Low-molecular weight inhibitors of normal cells have also been obtained from chick embryos. Specific and nonspecific mitotic inhibitors have been partially purified from mammalian and amphibian kidneys. The existence of a chalone, probably protein in nature, has been reported in amphibian kidneys. It may control growth and differentiation from the early stages of the pronephros, as well as kidney cell renewal in adult life. Numerous growth inhibitors isolated from the liver were active against various tumor cells both in vitro and in vivo.
Context and Competence in Work with Children and Youth

With the awareness that all interactions in child and youth care work occur in unique contexts, the authors explore how child and youth care workers use their understanding of context in their work with children and youth. A frame for learning how to recognize, change, and create context and suggestions for setting standards and evaluating workers' performance are also provided.
A Bayesian approach for correcting Tn5 transposition bias in ATAC-seq footprinting

ATAC-seq exploits the observation that the pattern of transposition of a hyperactive Tn5 transposase in native chromatin mirrors genome-wide chromatin accessibility. It has been suggested that transposition observed around transcription factor binding motifs can be used to assess their occupancy in the form of footprints. However, we show that the vast majority of footprints observed at transcription factor motifs in ATAC-seq data spuriously arise from the intrinsic sequence-dependent transposition site bias of Tn5 and are also observed in naked DNA. We demonstrate that the Tn5 transposition bias can be corrected using existing tools for sequence bias correction and a novel estimate of global occupancy in order to produce more reliable estimates of footprints.
Estuarine Dissolved Oxygen History Inferred from Sedimentary Trace Metal and Organic Matter Preservation

Environmental history recorded in estuarine sediment describes water quality regimes through the use of geochemical and biological proxies. We collected sediment cores from two locations in the Coos Estuary, Oregon, at South Slough and Haynes Inlet, spanning from ~ 1680 AD to the present. To reconstruct the historical water column oxygen in the estuary, we measured geochemical proxies including organic matter, magnetic susceptibility, and elemental composition, and we constructed sediment chronologies using the Pb210 profile and radiocarbon dates. Correlation of geochemical proxies and a detailed 15-year record of dissolved oxygen observations supports the inference of dissolved oxygen (DO) history from these sediment cores: a novel finding for small, seasonal Pacific Northwest estuaries. Geochemical evidence suggests that over the last 300 years, annually or semi-annually averaged dissolved oxygen stress has been increasing at South Slough, while remaining stable or even decreasing at Haynes inlet. This history was explained by changing climatic and land-use effects on erosion and organic matter as well as the role of shipping channel maintenance in providing a dissolved oxygen reservoir at Haynes Inlet relative to the more isolated South Slough.
Environmental and landscape influences on the spatial and temporal distribution of a cattle herd in a South Texas rangeland

The multiple spatial and temporal parameters affecting cattle herd distribution and activity dynamics can significantly affect resource utilization but are not fully understood. The aim of this study was to determine whether current animal tracking technology and spatio-temporal analysis tools can be used to integrate multi-scale information on herd distribution patterns as a function of seasonal forage production, periods of the day, animal activity, and landscape features. Positional and activity information of 11 free-ranging cows within a 31-member herd was obtained at 5-min intervals by using GPS collars for 1 year within a 457-ha ranch in the semi-arid rangelands of South Texas. Forage biomass was calculated with satellite imagery. Spatial analysis of cattle distribution and landscape features was conducted with GIS. Herd spread was greatest during the growing season. Throughout the year, during midday, the herd showed smaller spread and greater use of shade patches than any other time of day. Cattle also aggregated under trees in winter, particularly during the night. There was no statistically significant overall pattern of seasonal changes in the use of water and supplemental feeding areas, but a trend toward highest use during the winter. However, significantly different diurnal patterns in the use of supplemental feed and water were observed within each season. This study found a strong influence of shade patches relative to the influence of water and supplemental feeding areas on the diurnal and seasonal movement patterns of cattle in shrub-dominated rangeland. Although this study used only 11 tracked cows in a 31-member herd, the results indicated that techniques such as seasonal and diurnal GPS tracking, GIS, and remote sensing data enable evaluation of multiple spatial and temporal dynamics of cattle distribution and activity patterns. The smaller spread during the dry winter season associated with the observed aggregation of individuals in water and supplemental feeding areas, may aid in determining the most critical times for providing supplemental resources and guide the allocation of those resources to areas not frequently used by cattle, thus stimulating the animals to visit unused sites during the non-growing season.
Assessment of mass spectrometry-based pain management testing in clinical laboratories across North America

Abstract Background Urine drug testing (UDT) is a useful tool in monitoring compliance to prescribed medication and can also help identify behaviors of drug misuse, abuse, and diversion. Mass spectrometry (MS)-based screening is recommended as the first-line of UDT for pain management patients; however, this testing comes with an inherent lack of standardization in methodologies and various analytical challenges. The objective of this study was to assess the current state of UDT for pain management in a cross-section of clinical laboratories in North America. Materials and methods A total of 10 blinded urine samples were sent to 6 laboratories across the United States and Canada. Urine samples containing drugs and/or metabolites of interest were included to represent different clinical scenarios commonly seen in pain management settings. Assessment was based on the ability of the laboratories to correctly identify drugs and provide a meaningful interpretation of the findings (when offered by the performing laboratory). Results Across the laboratories involved in the study, 85% of tests correctly identified and appropriately reported the drugs present in the urine samples. Similarly, 84% of samples were considered to have an accurate interpretation included in the UDT report. Out of the total number of drugs included in the samples, 11% were not offered on every test menu. Conclusions This study revealed the lack of standardization in pain management UDT performed in a limited cross-section of clinical laboratories across North America.
COVID-1619: A Brief History of Racism

Racism is the use of Black people to achieve the goals of white people without regard to the personhood, humanity, and agency of Blacks. This essay explores this definition of racism by tracing the influence of the twin institutions of law and religion in creating and maintaining the slave system in early colonial America. The essay then demonstrates the pernicious and persistent nature of racism by mapping this definition onto the current COVID-19 pandemic and its disproportionate impact on Black Americans.
Multi-scale simulation of thrombus formation at LVAD inlet cannula connection: Importance of Virchow's triad

As pump thrombosis is reduced in current-generation ventricular assist devices (VAD), adverse events such as bleeding or stroke remain at unacceptable rates. Thrombosis around the VAD inlet cannula (IC) has been highlighted as a possible source of stroke events. Recent computational fluid dynamics (CFD) studies have attempted to characterize the thrombosis risk of different IC-ventricle configurations. However, purely CFD simulations relate thrombosis risk to ad-hoc criteria based on flow characteristics, with little consideration of biochemical factors. This study investigates the genesis of IC thrombosis including two elements of the Virchow's triad: Endothelial injury and Hypercoagulability. To this end a multi-scale thrombosis simulation that includes platelet activity and coagulation reactions was performed. Our results show significant thrombin formation in stagnation regions (|u|< 0.002 m/s) close to the IC wall. In addition, high shear-mediated platelet activation was observed over the leading-edge tip of the cannula which mirrors the thrombus deposition pattern observed clinically. The current study reveals the importance of biochemical factors to the genesis of thrombosis at the ventricular-cannula junction which can inform clinical decisions in terms of anticoagulation/antiplatelet therapy and guide engineers to develop more robust designs.
Structure and regulation of phospholipase Cβ and ε at the membrane.

Phospholipase C (PLC) β and e enzymes hydrolyze phosphatidylinositol (PI) lipids in response to direct interactions with heterotrimeric G protein subunits and small GTPases, which are activated downstream of G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs). PI hydrolysis generates second messengers that increase the intracellular Ca2+ concentration and activate protein kinase C (PKC), thereby regulating numerous physiological processes. PLCβ and PLCe share a highly conserved core required for lipase activity, but use different strategies and structural elements to autoinhibit basal activity, bind membranes, and engage G protein activators. In this review, we discuss recent structural insights into these enzymes and the implications for how they engage membranes alone or in complex with their G protein regulators.
Exploring Key Issues in Early Childhood and Technology: Edited by Chip Donohue, Routledge, New York, NY, 2019, 170 pp., $36.95, ISBN 9781138313804

When he began to compile and edit the collection, Exploring Key Issues in Early Childhood and Technology, it is difficult to imagine that Dr. Chip Donohue could have known how prescient and importa...
Inertial sensing of step kinematics in ambulatory patients with ALS and related motor neuron diseases

Amyotrophic lateral sclerosis (ALS) is a progressive disorder which impairs gait and elevates the risk for falls. Current methods of assessing gait in these patients are infrequent and subjective. ...
Structural Representation and the Ontology of Models

This chapter introduces a structural account of representation through partial structures and examines its ontological commitments. It is pointed out that structural approaches to scientific representation emphasize the crucial role played by structures in representing salient features of the world. It is common to present and, in some cases, even to reify such structures as abstract entities, in particular as set-theoretic constructs. Against this view, it is argued that no such reification is called for and that several strategies can be articulated to avoid commitment to set-theoretic structures in the defense of structural representation. In the end, one can favor the latter without being platonist about the former.
On the Application of Principal Component Analysis to Classification Problems

Principal Component Analysis (PCA) is a commonly used technique that uses the correlation structure of the original variables to reduce the dimensionality of the data. This reduction is achieved by considering only the first few principal components for a subsequent analysis. The usual inclusion criterion is defined by the proportion of the total variance of the principal components exceeding a predetermined threshold. We show that in certain classification problems, even extremely high inclusion threshold can negatively impact the classification accuracy. The omission of small variance principal components can severely diminish the performance of the models. We noticed this phenomenon in classification analyses using high dimension ECG data where the most common classification methods lost between 1 and 6% of accuracy even when using 99% inclusion threshold. However, this issue can even occur in low dimension data with simple correlation structure as our numerical example shows. We conclude that the exclusion of any principal components should be carefully investigated.
Racial Discrimination and Hazardous Drinking among Black Drinkers: The Role of Social Anxiety in the Minority Stress Model

Objective: Black Americans who consume alcohol experience worse alcohol-related outcomes. Thus, identifying psycho-sociocultural factors that play a role in hazardous drinking among Black individuals is vital to informing prevention and treatment efforts to reduce these disparities. Racial discrimination is related to hazardous drinking among Black adults, suggesting that some may drink (and continue to drink despite drinking-related problems) to alleviate negative affect (e.g., depression, anxiety) associated with discrimination. Yet, despite the social nature of both racial discrimination and drinking, no known research has examined the role of social anxiety in the relations among racial discrimination experiences and hazardous drinking. Method: Participants were 164 Black current drinking undergraduates. Results: Racial discrimination was significantly, positively correlated with hazardous drinking, depression, and social anxiety. Discrimination was indirectly related to hazardous drinking via social anxiety, but not depression. Further, discrimination was indirectly related to hazardous drinking via social anxiety alone and via the sequential effects of social anxiety and drinking to cope, but not via coping motives alone. It was also related to hazardous drinking via the sequential effects of depression and drinking to cope but not depression alone. Alternative model testing indicated that social anxiety was not related to hazardous drinking via discrimination, strengthening confidence in directionality of proposed relations. Conclusions: Negative affect (social anxiety, depression) appears to be related to hazardous drinking among those who experience more discrimination due in part to drinking to cope. Social anxiety plays an important role in the relation between discrimination and hazardous drinking among Black adults.
STREAMFLOW CHARACTERISTICS FROM CHANNEL SIZE

Flood-peak-frequency characteristics and mean flows of ungaged streams can be estimated from field measurements of channel width using relation based on data at gaged sites. Such relations have been developed by many investigators and are shown to be in good agreement. The technique, an engineering application of research in channel morphology, is most useful in regions where traditional methods may produce unreliable results. The need for better estimates of flow characteristics in the semiard regions of western United States led the United States Geological Survey to develop and publish estimating relations, and to establish guidelines (so far as possible) for measuring channel width. The paper describes practices and results by the USGS and others, evaluates the reliability of the technique, and suggests possible improvements. /Author/
United States and European Union Approaches to Internet Jurisdiction and Their Impact on E-Commerce

Technological innovation on the internet has brought the globalization trend to businesses and spawned an industry of "ecommerce" that has forever changed the way companies provide goods and services. Company web sites are accessible to virtually any internet user in the world. It is the unique global character of the internet to develop, however, that has prevented a uniform approach to jurisdiction over cases involving consumer transactions via the web. "Jurisdiction is the power and authority of a court to hear and determine a judicial proceeding." 1 The lack of a uniform legal framework for jurisdiction regarding internet transactions between different countries means companies face the possibility of being subject to any foreign legal judgments in which their web sites can be accessed. The unpredictability of jurisdiction makes it difficult for companies with web sites to limit their legal liability and inhibits the growth of e-commerce. This Comment will focus on the different approaches taken by the United States and European Union ("EU") towards determining jurisdiction and how this lack of uniformity limits the growth of the e-commerce industry because of the various strategies businesses must employ to limit their legal liability. Section 2 of this Comment gives an overview of the internet and how its infrastructure simultaneously encourages and hinders the development of e-commerce. Section 3 analyzes the U.S. and EU approaches for determining jurisdiction in internet cases.
Knowledge Acquisition Via Bottom-up Learning

Publisher Summary Different from existing models of skill learning that use a top-down approach—that is, from declarative knowledge to procedural knowledge or from explicit knowledge to implicit knowledge—this chapter proposes a bottom-up approach toward skill learning, which goes from procedural to declarative knowledge. The approach is demonstrated in the chapter using the CLARION (connectionist learning with adaptive rule induction online) model. The model based on the two-level dual-representation framework proposed that learns both types of knowledge in a bottom-up fashion by integrating connectionist, reinforcement, and symbolic learning methods to perform online learning and by using a combination of localist and distributed representation. It taps into the synergy of the two types of processes. Analyses of the literature on implicit versus explicit learning as well as other types of skill acquisition, including those in developmental psychology, are carried out to highlight the cognitive plausibility of our approach and its fit with human data. This chapter reviews human experiments that involve bottom-up skill learning while also describing bottom-up skill learning, as captured in a (simplified) computational model of the bottom-up approach, based on many related empirical and theoretical considerations. The chapter analyzes the approach (and especially the model) in terms of its ability to support important phenomena in bottom-up skill learning. The chapter highlights the commonalities and differences between the present approach and existing models of skill learning.
Retreat from Doma: The Public Policy of Same-Sex Marriage and a Theory of Congressional Power under the Full Faith and Credit Clause, The

Though it is inevitable that the issue of same-sex marriage will come before the Supreme Court, there are several different forms in which that question could arrive. While there could be a direct challenge from individuals in a state that does not permit same-sex marriage, it is equally likely that the challenge would concern interstate recognition of a same-sex marriage that is valid where performed. This latter type of case would invoke the constitutionality of the Defense of Marriage Act (DOMA), which states that no state is required to give full faith and credit to a same-sex relationship "treated as a marriage" under the law of another state. To answer this question, the Court may look directly at the constitutionality of prohibitions on same-sex marriage, because the failure to grant full faith and credit would not be legitimate if it rests on a public policy that is unconstitutional. This Article focuses on a second issue, on which there has been far less scholarly attention, the scope of Congress' authority to enact DOMA under the Full Faith and Credit Clause. The scope of the "public policy exception" regarding recognition of marriages validly performed in sister states is quite unsettled in Full Faith and Credit jurisprudence. With this backdrop, the question is whether Congress can interpret the Clause in a way that potentially diverges from the view of the Supreme Court. This article explores the boundaries of Congressional power, and whether it may enact legislation that either diminishes or enlarges the constitutional mandates of the Clause, as interpreted by the Supreme Court.
Remarks on canonical quantization

Differential geometric concepts in canonical quantization are discussed. Souriau'sespace fibre quantifiant is shown under certain conditions to be realized in contact structure. Illustrative examples of contact structures are examined.
Studies on the mechanism of oxidative phosphorylation. ADP promotion of GDP phosphorylation.

Abstract The process of ATP or GTP synthesis by bovine heart submitochondrial particles involves the binding of ADP or GDP to 3 exchangeable sites I, II, and III, and only upon substrate occupation of site III does rapid ATP or GTP synthesis take place. The dissociation constants determined for ADP were KADPI less than or equal to 10(-8) M, KADPII approximately 10(-7) M, and KADPIII (equivalent to apparent KADPm), approximately 3 x 10(-6) M in the low Km mode and KADPIII approximately 150 x 10(-6) M in the high Km mode. For GDP, these constants were KGDPI approximately 10(-6)-10(-5) M, KGDPII approximately 10(-4) M, and KGDPIII approximately 10(-3) M when NADH was the respiratory substrate (Matsuno-Yagi, A., and Hatefi, Y. (1990) J. Biol. Chem. 265, 82-88). Because of its low affinity for the above binding sites, GDP at micromolar concentrations does not lead to GTP synthesis. However, as shown in this paper, micromolar [GDP] undergoes phosphorylation in the presence of micromolar concentrations of ADP. Under these conditions, both ATP and GTP are synthesized. GDP inhibits ATP synthesis with KGDPi congruent to 7 microM, while ADP promotes GTP synthesis in a reaction that requires inorganic phosphate (apparent KPim = 2-3 mM) and is inhibited by uncouplers and inhibitors of the ATP synthase complex. The ADP-promoted GTP synthesis exhibited an "apparent" KGDPm = 4 microM and an "apparent" Vmax = 11 nmol of GTP (min.mg of protein)-1. These results were interpreted to mean that (a) micromolar [ADP] occupies sites I and II, allowing site III to bind and phosphorylate GDP, and (b) the KGDPm and Vmax calculated under these conditions represent values for the low Km-low Vmax mode of GTP synthesis, which in the absence of ADP is not detectable because of the positive cooperativity phase of GTP synthesis with the high KGDPII approximately 10(-4) M.
Sensitivity of the North American monsoon to antecedent Rocky Mountain snowpack

[1] While the inverse relationship between antecedent snowpack in the Himalayas and Tibetan Plateau and subsequent monsoon rainfall in South and East Asia has been extensively studied and established, the potential for such a relationship between Rocky Mountain snowpack and the North American monsoon remains uncertain. The present study represents the first modeling assessment of this vital predictability issue, going beyond simple observational correlations, which fail to identify causality or a mechanism, by applying a regional climate model to demonstrate that a deep Rocky Mountain snowpack tends to hinder the poleward advance of the subtropical ridge and associated monsoon rainfall into the Southwest United States. A deep, extensive snowpack increases the surface albedo and provides an abundant surge of soil moisture, both of which reduce tropospheric temperatures in spring and early summer, weakening the land-ocean thermal gradient and related monsoon system. This snow-monsoon relationship, which may serve as a vital prediction tool of summer rainfall in the semi-arid Southwest United States, has direct implications for regional water supply, streamflow, and biodiversity.
Conservation of an Intact vif Gene of Human Immunodeficiency Virus Type 1 during Maternal-Fetal Transmission

The human immunodeficiency virus type 1 (HIV-1) vif gene is conserved among most lentiviruses, suggesting that vif is important for natural infection. To determine whether an intact vif gene is positively selected during mother-to-infant transmission, we analyzed vif sequences from five infected mother-infant pairs following perinatal transmission. The coding potential of the vif open reading frame directly derived from uncultured peripheral blood mononuclear cell DNA was maintained in most of the 78,912 bp sequenced. We found that 123 of the 137 clones analyzed showed an 89.8% frequency of intact vif open reading frames. There was a low degree of heterogeneity of vif genes within mothers, within infants, and between epidemiologically linked mother-infant pairs. The distances between vif sequences were greater in epidemiologically unlinked individuals than in epidemiologically linked mother-infant pairs. Furthermore, the epidemiologically linked mother-infant pair vif sequences displayed similar patterns that were not seen in vif sequences from epidemiologically unlinked individuals. The functional domains, including the two cysteines at positions 114 and 133, a serine phosphorylation site at position 144, and the C-terminal basic amino acids essential for vif protein function, were highly conserved in most of the sequences. Phylogenetic analyses of 137 mother-infant pair vif sequences and 187 other available vif sequences from HIV-1 databases revealed distinct clusters for vif sequences from each mother-infant pair and for other vif sequences. Taken together, these findings suggest that vif plays an important role in HIV-1 infection and replication in mothers and their perinatally infected infants.
Effect of high-aspect-ratio microstructures on cell growth and attachment

Smooth muscle cells were cultured on a variety of high-aspect-ratio PMMA, PDMS, and SU-8 microstructures. Three basic microstructures were used in these experiments: columns, holes, and curved surfaces (microlenses). Typical PMMA features were over 500 /spl mu/m in height, while the SU-8 and PDMS structures averaged 150 /spl mu/m in height. The smooth muscle cells showed a clear preference for smooth surfaces as compared to the areas containing microstructures, though smooth muscle cells showed the ability to grow on all structures and to attach on the steep sidewalls associated with the microstructures. Smooth muscle cell alignment was not directly improved by the structures, though evidence indicates that smaller structures may be able to do so. Gap dimensions between columns were also shown to be critical with regard to cell spreading and movement.
Spin alignment in the production of charm and/or bottom vector mesons via heavy quark fragmentation.

We calculate the process-independent fragmentation functions for a b\ifmmode\bar\else\textasciimacron\fi{} antiquark to fragment into longitudinally and transversely polarized ${\mathit{B}}_{\mathit{c}}^{\mathrm{*}}$ ${(}^{3}$${\mathit{S}}_{1}$) mesons to leading order in the QCD strong coupling constant. In the special case of equal quark mass, we recover previous results for the fragmentation of c\ensuremath{\rightarrow}\ensuremath{\psi} and b\ensuremath{\rightarrow}\ensuremath{\Upsilon}. Various spin asymmetry parameters are defined as measures of the relative population of the longitudinally and transversely polarized vector meson states. In the heavy quark mass limit ${\mathit{m}}_{\mathit{b}}$\ensuremath{\rightarrow}\ensuremath{\infty}, our polarized fragmentation functions obey heavy quark spin symmetry, we therefore apply them as a model to describe the fragmentation of charm and bottom quarks into heavy-light mesons like ${\mathit{D}}^{\mathrm{*}}$ and ${\mathit{B}}^{\mathrm{*}}$. The spin asymmetry parameter, \ensuremath{\alpha}(z), is consistent with the existing CLEO data for ${\mathit{D}}^{\mathrm{*}}$. The scaling behavior of 〈z〉 is studied in detail. We find excellent agreement between the predictions of 〈z〉 from our fragmentation functions and the experimental data for ${\mathit{D}}^{\mathrm{*}}$ and ${\mathit{B}}^{\mathrm{*}}$ from the CERN LEP, CLEO, and ARGUS detectors. Finally, we also point out that the spin asymmetry depends significantly on the transverse momentum ${\mathit{p}}_{\mathrm{\ensuremath{\perp}}}$ of the vector mesons relative to the fragmentation axis.
Call Variation in the Bufo microscaphus Complex: Implications for Species Boundaries and the Evolution of Mate Recognition

Since the Modern Synthesis, many species concepts have considered characters mediating mate recognition essential to both the identification and definition of species. To explore divergence in mate recognition systems, calls were recorded and toads measured from all three species of the monophyletic Bufo microscaphus species complex including five populations of Bufo californicus, three populations of B. microscaphus, and one population of B. mexicanus. Call duration, dominant frequency, and pulse rate were significantly related to temperature, but not snout-vent length. When adjusted for temperature, calls of B. californicus had a significantly longer call duration, higher dominant frequency, and slower pulse rate than B. mexicanus and B. microscaphus, which did not differ from one another. However, the magnitude of variation among populations of B. californicus was similar to that between species. Discriminant analysis using call variables provided some separation of B. californicus and B. mexicanus from B. microscaphus, and cross-validation analysis correctly classified approximately 75% of B. californicus and B. mexicanus. Given only slight divergence in mate recognition systems between B. californicus and the other two taxa, the biological significance of this difference remains ambiguous. Comparisons among B. americanus group members indicate that hybridizing taxa may or may not exhibit divergence in advertisement calls. Maintenance of independently evolving lineages may be driven by other evolutionary mechanisms. These results support the notion that species recognition is best viewed as an effect of mate recognition.
An explosion of new endeavours: global humanitarian responses to industrialized warfare in the First World War era

This special issue explores the newly emerging history of humanitarianism and humanitarian aid during the First World War era. Broadly defined, humanitarianism invokes helping others, promoting the general welfare of mankind, and rescuing endangered people. Incorporating humanitarianism into the history of the war deepens our understanding of the political, diplomatic, social, and cultural contours of the conflict. It offers novel ways for thinking about such topics as the experience of civilians, the role of non-state organizations and individual actors in the war effort, and the nature of relations between neutrals, allies, and warring nations. It illuminates, moreover, the formation of ideas, structures, and practices of interventionism, and the ways in which humanitarian responses to war catalysed the formation of new forms of international interaction and awakened the world to the possibilities of aid amid disaster and in its wake. The dynamism of this new front of First World War history is revealed...
Regulation of the human long chain acyl-CoA dehydrogenase gene by nuclear hormone receptor transcription factors.

Abstract Mitochondrial fatty acid oxidation provides most of the energy required for myocardial function after birth. Long chain acyl-CoA dehydrogenase (LCAD) catalyzes the first step in the β -oxidation spiral. Our objective was to define regulatory elements of the human LCAD gene required for high levels of expression in mature heart and to locate elements suppressing gene expression in the fetus. We characterized the human LCAD gene structure and used in vitro transfection into cardiomyocytes and hepatoma cells of LCAD genomic fragments fused to a reporter gene to examine the effects of putative regulatory elements on transcription. Binding of transcription factors to nuclear hormone receptor consensus DNA binding domains was studied by gel shift experiments. The 200 bp of the human LCAD gene immediately upstream of the transcription initiation site are sufficient to act as a minimal promoter for the gene and provide some tissue-specific positive regulatory elements. The region from −1800 bp to −250 bp contains elements which markedly suppress transcription, including nuclear hormone receptor response elements. The dominant interaction is with the repressor factor, chicken ovalbumin upstream promoter transcription factor. We conclude that the developmental and tissue-specific regulation of the human LCAD gene is mediated, in part, by these nuclear hormone receptor transcription factors.
Comment on "Parasite selection for immunogenetic optimality".

Resistance to pathogens has been measured directly in several organisms by examining single-copy major histocompatibility complex (MHC) genes ([ 1 ][1], [ 2 ][2]). However, some MHC genes are found in multiple, tightly linked copies, as expected from gene duplication. Wegner et al . ([ 3 ][3])
Lumenal Vesicle Formation in the Endocytic Pathway

The ESCRT (endosomal sorting complex required for transport) machinery comprises a set of protein complexes that are responsible for sorting and trafficking into multivesicular bodies within the endocytic pathway as well as the topologically related processes of viral budding and cytokinesis. Recent studies suggest that ESCRT-III and the AAA+ ATPase VPS4 play a central role in driving lumenal vesicle formation and release. This talk will discuss recent studies that explore the role and regulation of these components in creating lumenal vesicles, and will discuss the significance and implications of this pathway for neuronal cell biology.
Evidence for superconductivity above 40 K in the La-Ba-Cu-O compound system.

An apparent superconducting transition with an onset temperature above 40 K has been detected under pressure in the La-Ba-Cu-O compound system synthesized directly from a solid-state reaction of La2O3, CuO, and BaCO3 followed by a decomposition of the mixture in a reduced atmosphere. The experiment is described and the results of effects of magnetic field and pressure are discussed.
Mechanisms of α-thrombin and β-thrombin-E formation: Use of ecarin for isolation of meizothrombin 1

Abstract Purified Ecarin from Echis carinatus venom converted purified bovine prethrombin 1 to meizothrombin 1. This involved only the breaking of an Arg-Ile bond. Meizothrombin 1 was purified. It was free of α-thrombin and was a single component by polyacrylamide gel electrophoresis. It had 14.5 times more esterase activity than proteolytic activity on fibrinogen. Like α-thrombin it degraded purified prothrombin to prethrombin 1. Meizothrombin 1 itself converted to α-thrombin plus prothrombin fragment 2 by autolysis, and also with purified Factor Xa. In the latter case, Factor V plus phospholipids or sodium taurocholate plus calcium ions accelerated the reaction. The amount of Factor Xa required in the presence of accessories was far less than needed for prothrombin as the substrate. The α-thrombin which formed converted to β-thrombin-E by autolysis. Purified meizothrombin 1 was dried from the frozen state without loss of activity, and the activity was stable at −20°C in 50% glycerol solution containing 0.05M phosphate buffer pH 6.5 and benzamidine 0.001M. A likely sequence for thrombin formation by Factor Xa begins with the production of meizothrombin possessing strong esterase and weak coagulant activity. Next, meizothrombin is converted to α-thrombin plus prothrombin fragment 1.2.
Diagnostic Blood Loss in the Patient Undergoing Head and Neck Surgery

Objective: To examine retrospectively the amount of blood lost solely for diagnostic purposes in a defined group of patients. Design: Retrospective medical chart review of a case series. Setting: Operating theater and surgical intensive care unit in a major tertiary care center. Patients: Thirty-nine consecutive patients with head and neck cancer undergoing major surgical procedures and requiring overnight intensive care unit monitoring. Main Outcome Measures: Patient medical records were analyzed for procedure, starting hematocrit reading, intraoperative estimated blood loss and intravenous fluids, operative time, history of blood product transfusion, blood lost for each phlebotomy encounter, and the immediate cost therefrom. Results: The mean diagnostic blood loss was 181 mL, which was 36% of estimated blood loss. In the group of 23 nontransfused patients, the average drop in hematocrit was 9.7%. This change in hematocrit correlated most strongly with operating time (P Conclusions: Diagnostic blood loss contributes significantly to the overall blood loss in the patient undergoing head and neck surgery. (Arch Otolaryngol Head Neck Surg 1994;120:707-710)
Crystal structure of a concentrative nucleoside transporter from Vibrio cholerae at 2.4 Å

Nucleosides are required for DNA and RNA synthesis, and the nucleoside adenosine has a function in a variety of signalling processes. Transport of nucleosides across cell membranes provides the major source of nucleosides in many cell types and is also responsible for the termination of adenosine signalling. As a result of their hydrophilic nature, nucleosides require a specialized class of integral membrane proteins, known as nucleoside transporters (NTs), for specific transport across cell membranes. In addition to nucleosides, NTs are important determinants for the transport of nucleoside-derived drugs across cell membranes. A wide range of nucleoside-derived drugs, including anticancer drugs (such as Ara-C and gemcitabine) and antiviral drugs (such as zidovudine and ribavirin), have been shown to depend, at least in part, on NTs for transport across cell membranes. Concentrative nucleoside transporters, members of the solute carrier transporter superfamily SLC28, use an ion gradient in the active transport of both nucleosides and nucleoside-derived drugs against their chemical gradients. The structural basis for selective ion-coupled nucleoside transport by concentrative nucleoside transporters is unknown. Here we present the crystal structure of a concentrative nucleoside transporter from Vibrio cholerae in complex with uridine at 2.4 A. Our functional data show that, like its human orthologues, the transporter uses a sodium-ion gradient for nucleoside transport. The structure reveals the overall architecture of this class of transporter, unravels the molecular determinants for nucleoside and sodium binding, and provides a framework for understanding the mechanism of nucleoside and nucleoside drug transport across cell membranes.
Experimental aortocoronary artery bypass grafting using a CO2 laser on the dog: Acute experiment

This study was designed to evaluate the feasibility of using laser tissue welding in aortocoronary bypass operation. Simulated aortocoronary bypass operations were performed on 10 dog hearts supported by extracorporeal circulation. Distal anastomoses between internal mammary artery and coronary artery were achieved using the laser technique, which includes four stay sutures of 7-0 polypropylene and tissue welding between the stays by the laser at a power level of 65 mW. Short-term luminal patency was 100% without stenosis by angiography. Microscopy and histology showed that CO2 laser caused medial change resulting in fusion with preservation of normal intimal morphology. The aortocoronary bypass operation using a CO2 laser is technically feasible, and this technique may open up a new method for patients with small peripheral coronary artery obstruction and for pediatric patients with certain conditions (eg, Kawasaki disease).
Max-Life Power Schedule for connectivity and biconnectivity in wireless ad hoc networks

Given the initial energy supplies and the maximal transmission power of the individual nodes in a wireless ad hoc network, a power schedule of duration t for a specified topological property P is a scheduling of the transmission powers of the individual nodes over the period [0, t] such that (1) the total amount of energy consumed by each node during the period [O, t] does not exceed its initial energy supply, (2) the transmission power of each node at any moment in the period [O, t] does not exceed its maximal transmission power, and (3) the produced network topology at any moment in the period [0, t] satisfies the property P. The problem Max-Life Power Schedule for P seeks a power schedule of the maximal duration for P. Let g be the golden ratio (1 + √5)/2, and e be an arbitrarily positive constant less than one. In this paper, we present a 9g/(1 - e)2-approximation algorithm for Max-Life Power Schedule for Connectivity, a 36g/(1 - e)2- approximation algorithm for Max-Life Power Schedule for 2-Node-Connectivity, and a 36g/(1 - e)2-approximation algorithm for Max-Life Power Schedule for 2-Edge-Connectivity.
Nonlinear oscillator behavior in the Jaynes-Cummings model

The driven Jaynes-Cummings model shows collapses and revivals of the mean photon number on a time scale much longer than the revival time for the two-state inversion. The behavior is essentially that of a nonlinear quantum oscillator with Hamiltonian {ital H}={radical}({cflx {ital A}}{sup {degree}}+{alpha})({cflx {ital A}}+{alpha}). {copyright} {ital 1996 The American Physical Society.}
P‐4: A Reconfigurable Stereomicroscopic Imaging System for Digital Pathology

A reconfigurable stereomicroscope system consisting of exchangeable light source, condenser, objectives, cameras, and 3D display was designed to allow the user to adjust the convergence angle, magnification and color rendering arbitrarily. To evaluate the depth resolution of the proposed 3D system, miniature 3D models were used as test patterns in psychophysical experiments.