cssi/SciSciGPT-SciSciNet huggingface dataset:
The HIV Databases: History, Design and Function

The HIV Sequence Database has been in existence now for 15 years, and its companion HIV Immunology Database for 6 years. The sequence database serves the HIV research community by bringing together the data accrued through the global sequencing effort into an accessible format, so that new studies can readily build on previous work. The database has also provided a center for HIV researchers to develop a useful nomenclature system, which has enabled more consistent and effective communication. The immunology database is integrated with the sequence database so that T-cell and B-cell antigenic regions can be studied from perspective sequence variability, the relative location of epitopes in proteins mapped, and studies cross-compared. Summaries of what is known about an epitope or antibody and literature links are available. Basic sequence analysis and immunological computational tools, designed specifically to aid HIV researchers but often with more general applications, have been developed at the database and are widely used. This kind of integrated database system can be useful for highly variable pathogens where extensive immunological characterization is underway. Rapid advances in sequencing and immunological method technologies will make combined database/computational facilitates an increasingly important aspect of pathogen-host studies.
NHL Team Production

In the past few years, the National Hockey League (NHL) has struggled financially. Teams within the NHL and the league itself have been struggling to make money, and last year the NHL season did not take place because of a labor dispute and resulting lockout between the players and owners. Therefore, this makes the NHL a very appropriate target for study. As previous research on various professional sports and the NHL have shown that winning teams are going to draw more fans, determining what makes NHL teams win games is a worthy endeavor. This study does just this. By using Ordinary Least Squares regression and a data set compiled on numerous individual and team statistics for the 1999-2000 through the 2003-2004 seasons, this study determines the various factors that contribute to Team Point production and Goals Allowed in the NHL. Of special note is the finding that Major Penalties, most commonly assessed for fighting, do in fact help NHL teams win games. Hopefully by seeing what aspects of the game lead to NHL team success, the league can determine how to draw more fans in order to make more revenue.
Nonlinear heart model predicts range of heart rates for 2:1 swinging in pericardial effusion

We analyze two mathematical models of Rigney and Goldberger (14) of heart swinging in large pericardial effusions. Both models represent the torques due to the outflow of blood from the heart. The first assumes that the duration of systole does not vary with heart rate (in beats/min), whereas the second assumes that it varies linearly with heart rate. We examine the motion of the heart for heart rates between 50 and 200 and for a range of initial positions and velocities. Both models predict that the heart swings once every other beat (2:1 swinging, giving rise to electrical alternans) in a discrete range of heart rates and swings once per beat otherwise; both models explain the appearance and disappearance of 2:1 swinging mathematically. The first model predicts a rate range from 105 to 116 for the occurrence of 2:1 swinging. The second model predicts the same qualitative behavior but with 2:1 swinging occurring at heart rates between 88 and 119, which agrees well with published clinical data showing 2:1 swinging at heart rates between 90 and 144. We describe an analysis program for ordinary differential equations that analyzed the models quickly and automatically.
A Bayesian hierarchical model for multiple imputation of urban spatio-temporal groundwater levels

Abstract Groundwater levels in urban areas are irregularly sampled and not well understood. Using a separable space–time Bayesian Hierarchical Model, we obtain multiple imputations of the missing values to analyze spatial and temporal groundwater level fluctuations in Los Angeles, CA.
Children’s executive function development and school socio-economic and racial/ethnic composition

Abstract The links between children’s literacy and mathematics development and school socio-economic and racial/ethnic composition are well documented. This work, however, has generally ignored the potential effects of school demographic characteristics on children’s executive function skills. Using data from ECLS-K: 2011 and piece-wise linear growth-curve models within a three-level hierarchical framework, we explore the associations between children’s executive function development and the socio-economic and racial/ethnic compositions of their schools in kindergarten through second grade. We find somewhat mixed results, with some evidence of school socio-economic compositional effects, particularly for initially lower-skilled children in kindergarten, but stronger indications that school racial/ethnic enrollments influence executive function development across age and skill levels.
Continuous Wave Laser Induced Damage Threshold of Ge28Sb12Se60 at 1.07 microns

The continuous wave laser-induced damage threshold of chalcogenide glass, Ge28Sb12Se60, is measured for a 5s exposure of 1.07 µm light focused to a spot size with 1/e diameter of 830 µm, following the ISO standards.
Detection of rare disease-related genetic variants using the birthday model

Abstract Motivation Exome sequencing is a powerful technique for the identification of disease-causing genes. A number of Mendelian inherited disease genes have been identified through this method. However, it remains a challenge to leverage exome sequencing for the study of complex disorders, such as schizophrenia and bipolar disorder, due to the genetic and phenotypic heterogeneity of these disorders. Although not feasible for many studies, sequencing large sample sizes (>10,000) may improve statistical power to associate more variants, while the aggregation of distinct rare variants associated with a given disease can make the identification of causal genes statistically challenging. Therefore, new methods for rare variant association are imperative to identify causative genes of complex disorders. Results Here we propose a method to predict causative rare variants using a popular probabilistic problem: The Birthday Model, which estimates the probability that multiple individuals in a group share the same birthday. We consider the probability and coincidence of samples sharing a variant akin to the chance of individuals sharing the same birthday. We investigated the parameter effects of our model, providing guidelines for its use and interpretation of the results. Using published data on autism spectrum disorder, hypertriglyceridemia in addition to a current case-control study on bipolar disorder, we evaluated this probabilistic method to identify potential causative variants. Several genes in the top results of the case-control study were associated with autism spectrum and bipolar disorder. Given that the core probability based on the birthday model is very sensitive to low recurrence, the method successfully tests the association of rare variants, which generally do not provide enough signal in commonly used statistical tests. Importantly, the simplicity of the model allows quick interpretation of genomic data, enabling users to select gene candidates for further biological validation of specific mutations and downstream functional or other studies. Availability https://github.com/yberstein/Birthday-Alqorithmhttp://labshare.cshl.edu/shares/mccombielab/www-data/Birthday-Algorithm/Birthday-Alqorithm.html Contact yberstei@cshl.edu (or yaelberstein@gmail.com) Supplementary information Supplementary data are available online.
Maldistribution of pulmonary blood flow in patients after the Fontan operation is associated with worse exercise capacity

Maldistribution of pulmonary artery blood flow (MPBF) is a potential complication in patients who have undergone single ventricle palliation culminating in the Fontan procedure. Cardiovascular magnetic resonance (CMR) is the best modality that can evaluate MPBF in this population. The purpose of this study is to identify the prevalence and associations of MPBF and to determine the impact of MPBF on exercise capacity after the Fontan operation. This retrospective single-center study included all patients after Fontan operation who had maximal cardiopulmonary exercise test (CPET) and CMR with flow measurements of the branch pulmonary arteries. MPBF was defined as > 20% difference in branch pulmonary artery flow. Exercise capacity was measured as percent of predicted oxygen consumption at peak exercise (% predicted VO2). Linear and logistic regression models were used to determine univariate and multivariable predictors of exercise capacity and correlates of MPBF, respectively. A total of 147 patients who had CMR between 1999 and 2017 were included (median age at CMR 21.8 years [interquartile range (IQR) 16.5–30.6]) and the median time between CMR and CPET was 2.8 months [IQR 0–13.8]. Fifty-three patients (36%) had MPBF (95% CI 29–45%). The mean % predicted VO2 was 63 ± 16%. Patients with MPBF had lower mean % predicted VO2 compared to patients without MPBF (60 ± 14% versus 65 ± 16%, p = 0.04). On multivariable analysis, a lower % predicted VO2 was independently associated with longer time since Fontan, higher ventricular mass-to-volume ratio, and MPBF. On multivariable analysis, only compression of the branch pulmonary arteries by the ascending aorta or aortic root was associated with MPBF (OR 6.5, 95% CI 5.6–7.4, p < 0.001). In patients after the Fontan operation, MPBF is common and is independently associated with lower exercise capacity. MPBF was most likely to be caused by pulmonary artery compression by the aortic root or the ascending aorta. This study identifies MPBF as an important risk factor and as a potential target for therapeutic interventions in this fragile patient population.
Abstract 164: Synthetic High-Density Lipoprotein Cholesterol Scavengers for the Treatment of Niemann-Pick C Disease

Background: Niemann-Pick C disease (NPC) is genetic disorder caused by an accumulation of unesterified cholesterol in late endosomes and lysosomes due to defects in NPC genes. The levels of ABCA1 g...
TIM-1 serves as a receptor for Ebola virus in vivo, enhancing viremia and pathogenesis.

Background T cell immunoglobulin mucin domain-1 (TIM-1) is a phosphatidylserine (PS) receptor, mediating filovirus entry into cells through interactions with PS on virions. TIM-1 expression has been implicated in Ebola virus (EBOV) pathogenesis; however, it remains unclear whether this is due to TIM-1 serving as a filovirus receptor in vivo or, as others have suggested, TIM-1 induces a cytokine storm elicited by T cell/virion interactions. Here, we use a BSL2 model virus that expresses EBOV glycoprotein to demonstrate the importance of TIM-1 as a virus receptor late during in vivo infection. Methodology/Principal findings Infectious, GFP-expressing recombinant vesicular stomatitis virus encoding either full length EBOV glycoprotein (EBOV GP/rVSV) or mucin domain deleted EBOV glycoprotein (EBOV GPΔO/rVSV) was used to assess the role of TIM-1 during in vivo infection. GFP-expressing rVSV encoding its native glycoprotein G (G/rVSV) served as a control. TIM-1-sufficient or TIM-1-deficient BALB/c interferon α/β receptor-/- mice were challenged with these viruses. While G/rVSV caused profound morbidity and mortality in both mouse strains, TIM-1-deficient mice had significantly better survival than TIM-1-expressing mice following EBOV GP/rVSV or EBOV GPΔO/rVSV challenge. EBOV GP/rVSV or EBOV GPΔO/rVSV in spleen of infected animals was high and unaffected by expression of TIM-1. However, infectious virus in serum, liver, kidney and adrenal gland was reduced late in infection in the TIM-1-deficient mice, suggesting that virus entry via this receptor contributes to virus load. Consistent with higher virus loads, proinflammatory chemokines trended higher in organs from infected TIM-1-sufficient mice compared to the TIM-1-deficient mice, but proinflammatory cytokines were more modestly affected. To assess the role of T cells in EBOV GP/rVSV pathogenesis, T cells were depleted in TIM-1-sufficient and -deficient mice and the mice were challenged with virus. Depletion of T cells did not alter the pathogenic consequences of virus infection. Conclusions Our studies provide evidence that at late times during EBOV GP/rVSV infection, TIM-1 increased virus load and associated mortality, consistent with an important role of this receptor in virus entry. This work suggests that inhibitors which block TIM-1/virus interaction may serve as effective antivirals, reducing virus load at late times during EBOV infection.
Income Inequality in the Great Recession did not Harm Subjective Health in Europe, 2003–2012

A rich tradition of research has addressed income inequality and health, but the issue has achieved a fresh currency with the reversals of economic fortunes wrought by the Great Recession. This paper analyses the degree to which changing inequality induced by the Great Recession impacted Europeans’ subjective health (self-rated health and satisfaction with health). To address this question, we analyse the multilevel European Quality of Life Survey conducted mainly in 2003, 2008, and 2012 which provides representative samples from 24 European countries at all three time points, as well as national-level data on inequality (Gini coefficient) and appropriate national-level and individual-level controls. We find that, net of GDP, inequality has no statistically significant impact before, during or after the Great Recession. Turning to determinants, our variance-components multi-level models controlling for known individual-level predictors show that inequality remains insignificant at all time points, while individual family income is strongly related to subjective health GDP per capita has little effect except indirectly through income. We also assessed impacts specifically for vulnerable, at-risk groups. Including GDP per capita, Gini coefficient, and individual level controls, our model explains about one quarter of the variance in health status (R-squared >.23). All in all, our results support a rational choice, materialist hypothesis: that absolute prosperity of the individual matters to subjective health, but income inequality does not, in Europe in this period. This supports a policy emphasis on increasing levels of pay, and on poverty relief, rather than on reducing inequality.
A linearly-acting variable-reluctance generator for thermoacoustic engines

Abstract A crucial element in a thermoacoustic power converter for reliable small-scale power generation applications is an efficient acoustic-to-electric energy converter. In this work, an acoustic-to-electric transducer for application with a back-to-back standing wave thermoacoustic engine, based on a linearly-acting variable-reluctance generator is proposed, built and experimentally tested. Static and dynamic experiments are performed on one side of the generator on a shaker table at 60 Hz with 5 mm peak-to-peak displacement for performance characterization. A theoretical and empirical model of the variable-reluctance generator are presented and validated with experimental data. A frequency scaling based on the empirical model indicates that a maximum power output of 84 W at 78% generator efficiency is feasible at the thermoacoustic engine’s operating frequency of 250 Hz, not considering power electronic losses. This suggests that the linearly-acting variable-reluctance generator can efficiently convert high frequency small amplitude acoustic oscillations to useful electricity and thus enables its integration into a thermoacoustic power converter.
Smoking Effects in Foot and Ankle Surgery: An Evidence-Based Review:

Background:The purpose of this article was to review the basic science pertaining to the harmful effects of cigarette smoke, summarize recent clinical outcome studies, and examine the benefits of s...
Emplaced care and atmospheric politics in unbreathable worlds

This paper contributes to emerging theories of unbreathable space by showing how breathers with asthma engage environments and atmospheres as the substrate of their everyday lives. Drawing on in-de...
Blackamerican Muslim Scholars and Leaders in New York City

Recent work has drawn attention to the state-led and media-driven discourse of "good" and "bad" Muslims. It is a flexible discourse, with benchmarks and shifting appraisals, that aims to mold American Muslims into "good" secular Muslims. Drawing on old Orientalist representations, this American Islamophobic framework strives to produce "good" Blackamerican Muslims through rendering them as invisible, voiceless, or under the control of allies of the U.S. secular power. The three ethnographic vignettes—a masjid fundraiser, two chaplains, and a political collective—demonstrate that Blackamerican Muslims scholars and leaders are not only disrupting this discursive project, but also undermining negative portrayals of Muslims and Islam more broadly. In addition, through their practice and discourse, these Blackamerican Muslim figures are formulating an emergent American Muslim religious identity.
Quantum Metrology Techniques for Axion Dark Matter Detection

Quantum metrology techniques can be used to dramatically improve the signal-to-noise ratio in experimental searches for dark matter axion waves. We first briefly review the cavity haloscope technique including quantum-limited measurements in the Glauber coherent state basis. Quantum non-demolition measurements in the Fock basis are then shown to offer much reduced background rates. Finally, we show that by preparing the cavity photon mode in a Fock state, the axion signal can be enhanced by stimulated emission.
Changes in the proportion of patients presenting with early stage colon cancer over time among Medicaid expansion and nonexpansion states.

251Background: In 2010, the Affordable Care Act required insurance plans to cover preventative screening, and the Medicaid expansion provision enabled participating states to increase Medicaid cove...
Assessing mental health stigma: Nurse practitioners' attitudes regarding managing patients with mental health disorders.

Background A contributing factor in the provision of suboptimal mental health care is the presence of stigmatizing attitudes among health care providers. Although numerous studies have investigated stigmatizing attitudes among physicians, nurses in psychiatric settings, and various populations of students, mental health stigma among nurse practitioners (NPs) has not yet been addressed. Purpose The purpose of this study was to assess NPs' attitudes and beliefs regarding working with individuals with a mental health disorder. Methods A cross-sectional descriptive design was used. Nurse practitioners attending a national practice conference completed a survey for demographic and practice information and a standardized measure for assessing stigmatizing attitudes regarding three mental health conditions: (a) anxiety/depression, (b) attention deficit hyperactivity disorder, and (c) substance use disorders (SUDs). Results A total of 141 NPs participated in this study. The most favorable attitudes were reported for working with individuals with anxiety/depression, and the least favorable attitudes were reported for working with those with an SUD. Implications for practice Stigmatizing attitudes are present among practicing NPs. Effective bias-reducing interventions are indicated to improve the patient-centered care NPs provide to individuals with mental health disorders.
Fixing Transit: The Case for Privatization

America's experiment with government ownership of urban transit systems has proven to be a disaster. Since Congress began giving states and cities incentives to take over private transit systems in 1964, worker productivity - the number of transit riders carried per worker - has declined by more than 50 percent; the amount of energy required to carry one bus rider one mile has increased by more than 75 percent; the inflation- adjusted cost per transit trip has nearly tripled, even as fares per trip slightly declined; and, despite hundreds of billions of dollars of subsidies, the number of transit trips per urban resident declined from more than 60 trips per year in 1964 to 45 in 2008. Largely because of government ownership, the transit industry today is beset by a series of interminable crises. Recent declines in the tax revenues used to support transit have forced major cuts in transit services in the vast majority of urban areas. Transit infrastructure - especially rail infrastructure - is steadily deteriorating, and the money transit agencies spend on maintenance is not even enough to keep it in its current state of poor repair. And transit agencies have agreed to employee pension and health care plans that impose billions of dollars of unfunded liabilities on taxpayers. Transit advocates propose to solve these problems with even more subsidies. A better solution is to privatize transit. Private transit providers will provide efficient transit services that go where people want to go. In order for privatization to take place, Congress and the states must stop giving transit agencies incentives to waste money on high-cost transit technologies.
Diving after SARS-CoV-2 (COVID-19) infection: Fitness to dive assessment and medical guidance

Scuba diving is a critical activity for commercial industry, military activities, research, and public safety, as well as a passion for many recreational divers. Physicians are expected to provide return-to-diving recommendations after SARS-CoV-2 (COVID-19) infection based upon the best available evidence, often drawn from experience with other, similar diseases. Scuba diving presents unique physiologic challenges to the body secondary to immersion, increased pressure and increased work of breathing. The long-term sequelae of COVID-19 are still unknown, but if they are proven to be similar to other coronaviruses (such as Middle East respiratory syndrome or SARS-CoV-1) they may result in long-term pulmonary and cardiac sequelae that impact divers' ability to safely return to scuba diving. This review considers available literature and the pathophysiology of COVID-19 as it relates to diving fitness, including current recommendations for similar illnesses, and proposes guidelines for evaluation of divers after COVID-19. The guidelines are based upon best available evidence about COVID-19, as well as past experience with determination of diving fitness. It is likely that all divers who have contracted COVID-19 will require a medical evaluation prior to return to diving with emphasis upon pulmonary and cardiac function as well as exercise capacity.
Opportunity areas for expanding Kirtland's warbler nesting habitat in Wisconsin and Upper Peninsula of Michigan

The Kirtland's warbler (Setophaga kirtlandii) is a long-distance Neotropical migratory bird with narrow suitable nesting habitat conditions consisting of dense, young (3–20 year) jack pine (Pinus banksiana) forests growing on nutrient-poor and well-drained soils primarily within northern Lower Michigan. The Kirtland's warbler was officially delisted after more than 50 years of conservation and management activities following initial listing in 1966 under the U.S. Endangered Species Preservation Act (Byelich et al. 1976). However, Kirtland's warbler is considered a conservation-reliant species, meaning their sustained presence on the landscape requires continued management intervention. Expanding their nesting habitat is a key element in continuing conservation actions outlined by the Kirtland's Warbler Conservation Team. To this end, known characteristics of jack pine ecosystems suitable for nesting Kirtland's warblers were used to identify opportunities for expanding their nesting habitat across Wisconsin and Michigan's Upper Peninsula.Visit the Research Data Archive to view the Geodatabase containing opportunity areas for expanding Kirtland's warbler nesting habitat in Wisconsin and Upper Peninsula of Michigan (.2 KB)
Estrategias de aprendizaje utilizadas por alumnos del segundo ciclo de secundaria de dos centros educativos de la regional 10 de Santo Domingo

The present quantitative research study studies the use of learning strategies in 80 middle-level students from 2 educational centers of the Regional 10 of Santo Domingo in the public and private sectors in the Dominican Republic. The general objective of this study is to analyze and contrast gender, grade and sector differences in the use of learning strategies. To assess the learning strategies used with greater and lesser frequency, the ACRA strategy scale was used (Roman and Gallego, 2008). The results showed that the learning strategies used the most, were the strategies for supporting information processing, that is, metacognitive, social and affective strategies. In contrast, the strategies used with less frequency were the information coding strategies, which involve a deep and complex processing where the previous information is integrated with the new one. On the other hand, the results indicated that there are significant differences in the use of learning strategies between the public and private sectors. In contrast, there were no significant differences in gender or grade.
Mitigation of Adversarial Policy Imitation via Constrained Randomization of Policy (CRoP).

Deep reinforcement learning (DRL) policies are vulnerable to unauthorized replication attacks, where an adversary exploits imitation learning to reproduce target policies from observed behavior. In this paper, we propose Constrained Randomization of Policy (CRoP) as a mitigation technique against such attacks. CRoP induces the execution of sub-optimal actions at random under performance loss constraints. We present a parametric analysis of CRoP, address the optimality of CRoP, and establish theoretical bounds on the adversarial budget and the expectation of loss. Furthermore, we report the experimental evaluation of CRoP in Atari environments under adversarial imitation, which demonstrate the efficacy and feasibility of our proposed method against policy replication attacks.
Integrating A Structured Research Proposal into An Undergraduate Glycobiology Class

A process for generating and writing an individual research proposal with or without access to advanced experimental techniques is described herein. This process was first included in a glycoconjugate biochemistry course to increase student interaction with more areas of the field, but the process was designed to be applicable elsewhere as well. In this series of assignments, students discover their interests in novel research areas, craft hypotheses, design experiments, and learn to anticipate experimental outcomes before participating in peer evaluation.
Scholarship Reconsidered: A Functional Core for Graduate Curricula

Higher education is involved in self-examination relative to its effectiveness in contemporary society. Criticisms from stakeholders—citizens, legislators, governing boards, students and alumni—feed the dialogue about the relevance of the role and mission of higher education in an era of accountability and decreasing resources. As Lynton and Elman (1987) indicated, new priorities must be established because “the nature and importance of knowledge in modern society are changing both quantitatively and qualitatively” (p. 1). Knowledge must be synthesized to be useful. This is as true for the student in the classroom as it is for state and federal legislators, the commissioners in communities, or citizens. While relationships to students and professional societies may have been priority audiences for faculty, the issues present in contemporary society make it essential that faculty in higher education facilitate the use of science and the knowledge base for decision-making in all aspects of society. Priorities for faculty must include responsibility for synthesis of the knowledge base as a means of creating better policy and improving programs. Several factors in higher education that have precluded effective use of the knowledge base in solving societal problems are described below. This is particularly true for problems in human services.
The future of simulation software: a panel discussion chair

Panelists present their position on the question, "Where do you see simulation software headed?" The panelists are given five areas as suggestions for their response: Internet applications; enterprise resource planning applications; embedded simulation; optimization; and object oriented simulation.
On the Detection and Tracking of a Class of Narrowband Sources

Some aspects of detecting and tracking narrowband acoustic sources that produce single or multiple sinusoids in the presence of broadband clutter are discussed. Experimental results using field data are included.
The Intuition Behind Sutton's Theory of Endogenous Sunk Costs

To explain why many manufacturing industries have remained highly concentrated, John Sutton has developed a new theory of endogenous sunk costs which predicts that industries with significant endogenous sunk costs will have a lower bound on concentration even as industry demand increases. Endogenous sunk costs are fixed costs that firms can choose to invest in, which affect the price-cost margin of a firm. Any optional fixed investments in quality, advertising, and cost-reducing plant, that allow the firm to raise its price or lower its variable costs, qualify as endogenous sunk costs. This paper cuts through the mathematical complexity of the model and examines the intuition behind the theory, to provide a better understanding of how and when the theory of endogenous sunk costs can be applied, and its limitations. How the incentive for firms to invest in endogenous sunk costs increases as the market expands, and how this can limit the number of firms that can profitably remain in the market, is discussed. The paper examines the key conditions required for this effect, and shows how the same basic results can be obtained even if some of Sutton's assumptions are relaxed. It also examines the reasons for the model's unusual result that in some circumstances, a market expansion can actually induce a reduction in the number of firms, contrary to the usual expectation in industrial organization theory. A proof is provided of the proposition that concentration is bounded below for the Cournot model. The paper then discusses how endogenous sunk costs are likely to have a significant impact on industrial development in ways that Sutton did not discuss, for example when firms have a choice of variable cost-reducing investments.
The ethical issue of international bribery: A study of attitudes among U.S. business professionals

Restrictions upon international bribery by U.S. business firms, as incorporated in the Foreign Corrupt Practices Act, have been controversial since this legislation was passed in 1977. Despite many attempts to repeal or change the law, it remains as originally enacted.
Enhancement of the steel quenching process by an electric field

An electric field is known to be able to increase considerably the heat flux during the boiling process by suppressing the occurrence of film boiling. This field enhancement technique can be applied to the steel quenching process to accelerate the cooling rate and thus increase the effective hardenability of the steel. This report describes a quench experiment performed with an electric field. The effective hardenability (depth of high hardness) of the samples quenched with the field was measured to be significantly higher than those quenched without the field. Examination of the microstructures showed that the application of the electric field increased the depth to which martensite formed in the sample.
Quantitative image quality evaluation of spiral MRI techniques under noisy conditions

Spiral sampling of k-space is a popular technique in fast MRI. Many methods are available for spiral acquisition and reconstruction. We used a Perceptual Difference Model (PDM) to evaluate these selections and to examine the effects of noise. PDM is a human observer model that calculates the visual difference between a “test image” and a “gold standard image.” PDM has been shown to correlate well with human observers in a variety of MR experiments including added noise, increased blurring, keyhole imaging, and spiral imaging. We simulated MR images from six different interleave patterns, seven different sampling levels, three different density compensation methods, and four different reconstruction options under zero noise and three noise levels. By comparing results with and without noise, we can separate noise effects from reconstruction errors. Comparing many different conditions, Voronoi (VOR) plus conventional regridding was good for high SNR data. In low SNR conditions, area density function (ADF) was better. One can also quantitatively compare different acquisition parameters; smaller numbers of interleaves and high number of samples were very desirable when noise was applied, because high frequency sampling was ensured. We conclude that PDM scoring provides an objective, useful tool for the assessment of spiral MR image quality and can greatly aid the design of MR acquisition and signal processing strategies.
Antimicrobial activity of stratum corneum lipids from normal and essential fatty acid-deficient mice.

Among the cutaneous effects of an essential fatty acid deficient (EFAD) diet are hyperdesquamation, increased trans-epidermal water loss (TEWL), and altered lipid profiles, characteristics also common to inflammatory dermatoses. Because fatty acids are antimicrobial, we examined the indigenous skin flora of normal and EFAD hairless mice, and compared the antimicrobial efficacy of lipids extracted from their stratum corneum. EFAD mice supported 100-fold more bacteria than normal mice, and were the only group from which staphylococcus aureus were routinely isolated. Despite this greater carriage, in vitro experiments demonstrated that EFAD lipids are more lethal than normal lipids against Streptococcus pyogenes, S. aureus, S. epidermidis, Micrococcus sp., and a coryneform. Skin fungi were equally susceptible to both extracts. After thin layer chromatography, the most active fractions were found to be glycophingolipids and phsopholipids. EFAD extracts had 35% more free fatty acids and 75% more glycophingolipids; normal extracts had more triglycerides and phospholipids. S. aureus strain 502A survived equally well on EFAD as on normal mice, normal lipids applied on EFAD mice had no additional effect, but EFAD lipids on normal mice brought about a 35% reduction of the inoculated bacteria. If the mice were pretreated with alcohol, carriage of strain 502A was reduced by 71%. If instead the mice were previously washed with acetone to increase TEWL, a 97% reduction of the staphylococcus occurred. The application of normal flora to such acetone-washed mice decreased the efficacy to 76%. EFAD and normal lipids on human subjects were equally ineffective in eliminating strain 502A. Results suggest that in vivo the normal flora regulates the killing of pathogenic microorganisms by potent EFAD skin lipids.
Energy-feedback tradeoff in the best-M OFDMA systems

Feedback is required to design energy efficient schemes in order to adapt the transmitter processing to the channel characteristics and to boost the system performance, but the feedback load is an important parameter with a large impact on the system performance. Its signalling load represents a main challenge for multi-carrier and multiuser systems, where its optimization is required. Orthogonal Frequency Division Multiple Access (OFDMA) is a multi-carrier technique currently under consideration in several commercial standards, where the feedback over each one of its subcarriers induces a non-acceptable signalling load in the system. A tradeoff is obtained between the two conflicting objectives, where this paper studies the feedback effect and how it induces additional energy consumption in the system. Closed form expressions are obtained for the amount of wasted energy where the effect of all the involved parameters is shown.
Historical review of and current progress in coal-resource estimation in the United States.

Nine estimates of the coal resources of the United States have been published in the past 71 years. Although many details of these estimates differ markedly, the 1913, 1922, and 1974 estimates are surprisingly similar. Some differences are due to increased geologic data, others reflect changes in terminology, definitions, criteria, guidelines, and methodologies used for estimating coal resources and reserves during the last 100 years. Because of the increased data and changes, many of the early estimates are not particularly useful in modern resource assessments. Preliminary definitions that are being prepared in 1980 by the U.S. Geological Survey are compared with those published in 1976 and currently in use. Anticipated results of the new definitions are to lessen existing confusion about estimation procedures, to make such procedures easier and more precise, and to promote use of a commonly accepted terminology accompanied by standardized definitions, criteria, guidelines, and methodologies for estimating coal resources.
τ Self-Association: Stabilization with a Chemical Cross-Linker and Modulation by Phosphorylation and Oxidation State

tau is a major component of paired helical filaments found in the neurofibrillary tangles of Alzheimer's diseased brain. However, the mechanism or mechanisms responsible for the association of tau to form these aggregates remains unknown. In this study, the role of intermolecular disulfide bonds in the formation of higher order oligomers of bovine tau and the human recombinant tau isoform T3 was examined using the chemical cross-linking agent disuccinimidylsuberate (DSS). In addition, the role of phosphorylation and oxidation state on the in vitro self-association of tau was studied using this experimental model. Stabilization of tau-tau interactions with DSS indicated that intermolecular disulfide bonds probably play a predominant role in dimer formation, but the formation of higher order oligomers of tau cannot be attributed to these bonds alone. tau-tau interactions were significantly decreased either by blocking Cys residues or by exposing the tau to a reducing (nitrogen and dithiothreitol), instead of an oxidizing, environment. tau self-association was also significantly decreased by prior phosphorylation with calcium/calmodulin-dependent protein kinase II. Phosphorylation by cyclic AMP-dependent protein kinase or dephosphorylation by alkaline phosphatase did not alter tau self-assembly. These data suggest a role for several factors that may modulate tau self-association in vivo.
A visible spectrophotometric assay for submicrogram quantities of DNA, including PCR-amplified DNA

Abstract The use of the cationic thiazine dye toluidine blue for solution measurements of DNA in the submicrogram range was studied with particular regard to the measurement of the small quantities of DNA synthesized in a typical polymerase chain reaction (PCR). Tolouidine blue shows a decrease in absorption at its wavelength of maximal absorption, 628 nm, on binding DNA in low concentrations. Using toluidine blue at 2 × 10−5 M, there was a linear response to increasing DNA concentrations up to 2000 ng of DNA in a 500 μl assay. The lower limit of detection was 24 ng of DNA. The assay was found to be sufficiently sensitive to measure the DNA produced in a PCR, and to distinguish PCRs that amplified a product from those in which amplification did not occur. The effects of selected metal ions and nonmetals on the assay were assessed. Of the compounds tested only sodium dodecyl sulfate was found to be incompatible with the assay. Compared to other colorimetric DNA assays, the toluidine blue assay is 10- to 100-fold more sensitive, approaching the sensitivity achieved by fluorometric DNA assays. The color change on binding DNA is immediate, and takes place at room temperature, thus allowing for rapid measurements to be made. The toluidine blue assay extends the useful range of visible spectrophotometric DNA assays well into the submicrogram range and is suitable for detection and measurement of the microgram quantities of DNA produced in a typical PCR.
THE EFFECT OF INTRASPECIFIC SAMPLE SIZE ON TYPE I AND TYPE II ERROR RATES IN COMPARATIVE STUDIES

Comparative studies have increased greatly in number in recent years due to advances in statistical and phylogenetic methodologies. For these studies, a trade-off often exists between the number of species that can be included in any given study and the number of individuals examined per species. Here, we describe a simple simulation study examining the effect of intraspecific sample size on statistical error in comparative studies. We find that ignoring measurement error has no effect on type I error of nonphylogenetic analyses, but can lead to increased type I error under some circumstances when using independent contrasts. We suggest using ANOVA to evaluate the relative amounts of within- and between-species variation when considering a phylogenetic comparative study. If within-species variance is particularly large and intraspecific sample sizes small, then either larger sample sizes or comparative methods that account for measurement error are necessary.
Sidium-dependent ion cotransport in steady-state Ehrlich ascites tumor cells

The Ehrlich tumor cell possesses and anion-cation cotransport system which operates as a bidirectional exchanger during the physiological steady state. This cotransport system, like that associated with the volume regulatory mechanism (i.e. coupled net uptake of Cl−+Na+ and/or K+) is Cl−-selective and furosemide-sensitive, suggesting the same mechanism operating in two different modes. Since Na+ has an important function in the volume regulatory response, its role in steady-state cotransport was investigated. In the absence of Na+, ouabain-insensitive K+ and DIDS-insensitive Cl− transport (KCl cotransport) are low and equivalent to that found in 150mm Na+ medium containing furosemide. Increasing the [Na+] results in parallel increases in K+ and Cl− transport. The maximum rate of each (18 to 20 meq/(kg dry wt)·min) is reached at about 20mm Na+ and is maintained up to 55mm. Thus, over the range 1 to 55mm Na+ the stoichiometry of KCl cotransport is 1∶1. In contrast to K+ and Cl−, furosemide-sensitive Na+ transport is undetectable until the [Na+] exceeds 50mm. From 50 to 150mm Na+, it progressively rises to 7 meq/(kg dry wt)·min, while K+ and Cl− transport decrease to 9 and 16 meq/(kg dry wt)·min, respectively. Thus, at 150mm Na+ the stoichiometric relationship between Cl−, Na+ and K+ is 2∶1∶1. These results are consistent with the proposal that the Cl−-dependent cation cotransport system when operating during the steady state mediates the exchange of KCl for KCl or NaCl for NaCl; the relative proportion of each determined by the extracellular [Na+].
Gap formation and defect states in tetrahedral amorphous carbon

We present a model of tetrahedral amorphous carbon ~with density 3.0 g cm) obtained from selfconsistent plane-wave ~Car-Parrinello! methods. This model is closely related to one we presented earlier @Phys. Rev. B 49, 16 415 ~1994!#, except for an even greater tendency toward sp p pair and chain formation. We also discuss, in general terms, appropriate means for comparing models generated with different methods and emphasize the need for a proper relaxation of ionic coordinates. @S0163-1829~96!03032-9#
Magnetic susceptibility of zinc alloys: Axial ratio dependence

Abstract The applicability of the axial ratio as a scaling parameter for both the temperature and composition dependence of Δχ 0 = χ ‖− χ ⊥ in the low magnetic field limit is demonstrated for dilute alloys of Cd and of Hg in Zn.
Using a cruise report to generate XML metadata

Since 2005 metadata generation at the Center for Coastal and Ocean Mapping/Joint Hydrographic Center has slowly evolved from a painful and tedious process of copying and pasting, to generate hundreds of files, to using an automated system that generates 90% of the needed metadata from the data collected on cruises. However there remained one piece missing to the automated system- the wordy part of the metadata that deals with information such as the attribute accuracy report, abstract and the process description. This information cannot be mined from the raw survey data. This paper illustrates how to generate a template from a Microsoft Word based cruise report that can be used in conjunction with another template (generated from the raw data collected on a cruise) to create XML metadata ready for submission to the NOAA/National Geophysical Data Center.
Full exploitation of process variation space for continuous delivery of optimal delay test quality

The increasing magnitude of process variations individualizes effectively each chip, necessitating distinct quantities of test resources for each in order to optimize overall delay test quality without exceeding set test budgets. This paper proposes an analytical framework that delivers the optimal test time assignment per chip in order to minimize the delay defect escape rate. Adjustment of the chip-specific test time in the continuous process variation space is attained through an adaptive test flow that utilizes process data measurements from the device under test. The results evince that a substantial improvement in the delay test quality can be obtained at no increase whatsoever to test time consumed by conventional test flows.
Role of intracoronary thrombus in acute complications during percutaneous transluminal coronary angioplasty

Coronary angiograms from 2,372 consecutive patients who underwent percutaneous transluminal coronary angioplasty (PTCA) were retrospectively reviewed for the presence of intracoronary thrombus (ICT) before dilatation. Patients with evolving acute myocardial infarction and those receiving thrombolytic therapy were excluded from analysis. Coronary artery thrombus was present in 126 patients (6%) (group 1). When compared to 2,246 patients (group 2) without ICT, group 1 had a higher incidence of unstable angina, 74% vs. 66% (less than 0.06), previous myocardial infarction, 59% vs. 37% (P less than .0001), and history of a recent myocardial infarction, 28% vs. 9% (P less than .0001). Patients with predilatation intracoronary thrombus had a higher risk for acute occlusion, 6% vs. 2% (P less than .002); however, the incidence of emergency coronary bypass surgery and myocardial infarction was similar in both groups. Therefore, the presence of predilatation intracoronary thrombus heralds an increased risk of acute occlusion, but not myocardial infarction or emergency coronary artery bypass surgery.
Airborne ultraviolet studies of Venus

Airborne ultraviolet studies of Venus were carried out during the NASA-ESO Space Shuttle simulation program. The primary wavelength region monitored was between 2950 and 3350 A in the third order. Measurements of solar radiation reflected from Venus were obtained on five flights at elevation angles of 15-30 deg. Direct solar and lunar spectra were obtained for the same elevation angles during two of the flights. Typical solar and Venutian spectra are presented.