cssi/SciSciGPT-SciSciNet huggingface dataset:
Modeled prenatal exposure to per- and polyfluoroalkyl substances in association with child autism spectrum disorder: A case-control study.

Background/objective Per- and polyfluoroalkyl substances (PFAS) display neurobehavioral toxicity in laboratory animal studies. We examined associations of modeled prenatal maternal exposure to PFAS with child diagnosis of autism spectrum disorder (ASD). Methods Participants were 453 mother-child pairs from CHARGE (CHildhood Autism Risk from Genetics and Environment), a population-based case-control study. Children underwent psychometric testing and were clinically confirmed for ASD (n = 239) or typical development (TD, n = 214). At the end of the clinic visit, maternal blood specimens were collected. We quantified nine PFAS in maternal serum samples collected when their child was 2-5 years old. As surrogate in utero exposure, we used a model built from external prospective data in pregnancy and 24 months post-partum and then reconstructed maternal PFAS serum concentrations during pregnancy in this case-control sample. We used logistic regression to evaluate associations of modeled prenatal maternal PFAS concentrations with child ASD. Results Modeled prenatal maternal perfluorohexane sulfonate (PFHxS) and perfluorooctane sulfonate (PFOS) were borderline associated with increased odds of child diagnosis of ASD (per nanogram per milliliter increase: odds ratio [OR] = 1.46; 95% confidence interval [CI]: 0.98, 2.18 for PFHxS, OR = 1.03; 95% CI: 0.99, 1.08 for PFOS). When compared to the lowest quartile (reference category), the highest quartile of modeled prenatal maternal PFHxS was associated with increased odds of child diagnosis of ASD (OR = 1.95; 95% CI: 1.02, 3.72). Conclusions In analyses where modeled prenatal maternal PFAS serum concentrations served as in utero exposure, we observed that prenatal PFHxS and PFOS exposure, but not other PFAS, were borderline associated with increased odds of child diagnosis of ASD. Further studies in which PFAS concentrations are prospectively measured in mothers and children at a range of developmental stages are needed to confirm these findings.
140 A pilot implementation study of saferteens-pc: a violence intervention for adolescent primary care patients

Statement of Purpose Youth violence is a leading cause of morbidity and mortality. Adolescent primary care visits provide an opportunity for violence screening and delivery of interventions, which are not typically offered in this setting. Thus, we examined implementation of an evidenced-based behavioral intervention (SafeERteens) in primary care. Methods/Approach Adolescents (ages 14–18) reporting past year aggression on a screening survey were eligible. A quasi-experimental deign was used, enrolling a comparison sample (e.g., resource brochure) and an intervention sample, which consisted of clinic staff delivering a 30-minute Motivational Interviewing-based brief intervention, followed by automatic text message boosters over 8 weeks. Follow-up surveys were complete at 3-months. Results Overall, about half (50.0%; 56.6%) of youth screened positive, with 110 enrolled (n=49 comparison; n= 61 intervention). Intervention delivery characteristics varied by clinic, including completion (75.9%; 62.5%), modality (100% telehealth; 60% telehealth/40% in-person), and enrollment in text messages (81.8%; 55.0%). In analyses comparing relative changes over time (using an intent-to-treat approach), the intervention group showed significantly greater reductions in severe peer aggression (p Conclusions Findings support the feasibility and preliminary effectiveness of delivering violence interventions in primary care, with key lessons learned informing future translation of behavioral interventions into routine care in primary care. Significance/Contribution to Injury and Violence Prevention Primary care is a useful setting to identify adolescents involved with violence, and deliver interventions, which could reduce injury and improve health outcomes.
Protective Adaptive Immunity Against Severe Acute Respiratory Syndrome Coronaviruses 2 (SARS-CoV-2) and Implications for Vaccines

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging human coronavirus responsible for coronavirus disease 2019 (COVID-19), a predominantly respiratory disease that has become a global pandemic. Millions of people worldwide are suffering from COVID-19, and hundreds of thousands of those infected have died. Nevertheless, many more people who have been infected with SARS-CoV-2 are asymptomatic or suffer a mild disease characterized by dry cough and mild fever. This new pandemic poses a threat to public health on a global scale, and an intervention to prevent continued spread of SARS-CoV-2 virus is of the utmost importance. To assess preventive and therapeutic strategies, it is imperative to understand the pathogenesis and immune response against SARS-CoV-2. In this review, we concentrate on the protective adaptive immune response elicited by this novel coronavirus as well as requirements for a successful vaccine inducing optimal protection.
Discovery of Syndiotactic Polystyrene: Its Synthesis and Impact

This Editorial discusses two seminal Macromolecules publications by Ishihara et al. concerning the synthesis of syndiotactic polystyrene. In a 1986 communication (Macromolecules 1986, 19, 2464), th...
Molecular Remodeling in Populus PdKOR RNAi Roots Profiled Using LC-MS/MS Proteomics

Plant endo-β-1,4-glucanases belonging to the Glycoside Hydrolase Family 9 have functional roles in cell wall biosynthesis and remodeling via endohydrolysis of (1→4)-β-d-glucosidic linkages. Modification of cell wall chemistry via RNA interference (RNAi)-mediated downregulation of Populus deltoides KORRIGAN (PdKOR), an endo-β-1,4-glucanase familygene was shown to have functional consequences on the composition of secondary metabolome and the ability of modified roots to interact with beneficial microbes. The molecular remodeling that underlies the observed differences at metabolic, physiological, and morphological levels in roots is not well understood. Here a liquid chromatography (LC)-tandem mass spectrometry (MS/MS)-based proteome profiling approach is used to survey the molecular remodeling in root tissues of PdKOR and control plants. A total of 14316 peptides are identified and these mapped to 7139 P. deltoides proteins. Based on 90% sequence identity, the measured protein accessions represent 1187 functional protein groups. Analysis of Gene Ontology (GO) categories and specific individual proteins show differential expression of proteins relevant to plant-microbe interactions, cell wall chemistry, and metabolism. The new proteome dataset serves as a useful resource for deriving new hypotheses and empirical testing pertaining to functional roles of proteins and pathways in differential priming of plant roots to interactions with microbes.
Decision support model for cybersecurity risk planning: A two-stage stochastic programming framework featuring firms, government, and attacker

Abstract We study the decision-making problem in cybersecurity risk planning concerning resource allocation strategies by government and firms. Aiming to minimize the social costs incurred due to cyberattacks, we consider not only the monetary investment costs but also the deprivation costs due to detection and containment delays. We also consider the effect of positive externalities of the overall cybersecurity investment on an individual firm’s resource allocation attitude. The optimal decision guides the firms on the countermeasure portfolio mix (detection vs. prevention vs. containment) and government intelligence investments while accounting for actions of a strategic attacker and firm budgetary limitations. We accomplish this via a two-stage stochastic programming model. In the first stage, firms decide on prevention and detection investments aided by government intelligence investments that improve detection effectiveness. In the second stage, once the attacker’s actions are realized, firms decide on containment investments after evaluating the cyberattacks. We demonstrate the applicability of our model via a case study. We find that externality can reduce the government’s intelligence investment and that the firm’s detection investment receives priority over containment. We also note that while prevention effectiveness has a decreasing impact on intelligence, it is beneficial to spend more on intelligence given its increasing returns to the reduction of social costs related to cybersecurity.
Real-Time Bayesian Nonparametric Prediction of Solvency Risk

Insurance regulation often dictates that insurers monitor their solvency risk in real time and take appropriate actions whenever the risk exceeds their tolerance level. Bayesian methods are appealing for prediction problems thanks to their ability to naturally incorporate both sample variability and parameter uncertainty into a predictive distribution. However, handling data arriving in real time requires a flexible nonparametric model, and the Monte Carlo methods necessary to evaluate the predictive distribution in such cases are not recursive and can be too expensive to rerun each time new data arrives. In this paper, we apply a recently-developed alternative perspective on Bayesian prediction based on copulas. This approach facilitates recursive Bayesian prediction without computing a posterior, allowing insurers to perform real time updating of risk measures to assess solvency risk, and providing them with a tool for carrying out dynamic risk management strategies in today's "big data"' era.
The Bacterial Perspective on Circadian Clocks

Prokaryotes were long thought to be incapable of expressing circadian (daily) rhythms. Research on nitrogen-fixing cyanobacteria in the 1980s squashed that dogma and showed that these bacteria could fulfill the criteria for circadian rhythmicity. Development of a luminescence reporter strain of Synechococcus elongatus PCC 7942 established a model system that ultimately led to the best characterized circadian clockwork at a molecular level. The conclusion of this chapter lists references to the seminal discoveries that have come from the study of cyanobacterial circadian clocks.
Retrospective Analysis of Retinal Imaging in COVID-19 Positive Patients at a Tertiary Eye Care Center

Purpose : Since the start of the COVID-19 pandemic, numerous authors have published data demonstrating retinal changes found in patients with COVID-19. These include differences in retinal vascular anatomy, hyper-reflective changes on optical coherence tomography (OCT), and signs of microvascular disease such as cotton wool spots and retinal hemorrhages. However, other authors have debated the validity of these findings and the effects of COVID-19 on the retina remain uncertain. Herein, we aim to retrospectively assess for retinal changes in patients infected by COIVD-19 who were seen at a tertiary eye care center. Methods : A retrospective review of patients who presented to Massachusetts Eye and Ear (Boston, MA, USA) between March 1st and October 31st, 2020 with a history of a positive COVID-19 polymerase chain reaction test was performed. Patients were included if they presented within 90 days of their first positive COVID-19 test and underwent color fundus photography and/or OCT of the macula. Results : A total of 119 eyes from 61 patients with mean age of 63 years and mean presentation of 60.4 days after first positive COVID-19 test (range 4 to 90 days) were included. Among 83 eyes which underwent OCT of the macula, inner retinal hyperreflective changes were seen in 16.9% (n=14), outer retinal hyper-reflective changes in 18.1% (n=15), intra-retinal fluid in 28.9% (n=24), and sub-retinal fluid in 14.5% (n=12). Among 48 eyes which underwent color fundus photography, retinal hemorrhage was seen in 27.1% (n=13), optic disc edema in 2.1% (n=1), and cotton wool spots in none of the eyes. Among 109 eyes which underwent a documented exam of the posterior segment, retinal hemorrhage was seen in 23.9% (n=26), optic disc edema in 2.75% (n=3), and cotton wool spots in 3.7% (n=4). Sub-analysis of 70 eyes from 41 patients with no alternative retinal pathology (diabetic retinopathy, retinal vein occlusion, etc.) to potentially cause the above findings revealed that none of the eyes demonstrated any of the above exam findings on OCT macula (n=35), fundus photography (n=28), or documented exam (n=66). Conclusions : While a number of patients seen after COVID-19 infection demonstrated retinal findings, all could be explained by pre-existing retinal conditions. In a sub-group of eyes without pre-existing retinal disease, we did not identify any retinal findings that could be attributed to COVID-19.
Humoral and T-cell responses to SARS-CoV-2 vaccination in multiple sclerosis patients treated with ocrelizumab

Abstract Background The COVID-19 epidemic raises important questions about the efficacy of vaccines for people treated with ocrelizumab, an anti-CD20 therapy. Ocrelizumab has been shown to reduce the humoral response to SARS-CoV-2 infection and vaccination, but the T-cell response to vaccination has not been fully characterized. We sought to provide data regarding B and T-cell mediated responses to SARS-CoV-2 vaccination in ocrelizumab-treated patients, and to determine what variables correlate with vaccine immunogenicity. We hypothesized that patients without a humoral response to SARS-CoV-2 vaccination would still have intact T-cell responses. Methods We conducted a prospective, observational, single center cohort study of patients with MS treated with either ocrelizumab or natalizumab as a comparator between March 2, 2021, and July 1, 2021. Eligible patients were age 18 to 55 and had no known prior infection with, or vaccination against, SARS-CoV-2. Patients with prior use of immunosuppressive or chemotherapeutic agents, or treatment with any anti-CD20 therapy other than ocrelizumab within 12 months of enrollment, were excluded. The Roche Elecsys anti-SARS-CoV-2 S immunoassay was performed prior to and 3–4 weeks post vaccination to evaluate the antibody response to SARS-CoV-2 spike IgG. The Adaptive Biotechnologies T-Detect COVID Test was performed to evaluate the adaptive T-cell immune response to SARS-CoV-2 in OCR-treated patients with no detectable antibodies. Data were analyzed using descriptive statistics, Fisher's exact test, and Wilcoxon rank sum. Results Forty-eight patients were enrolled in the study, 69% treated with ocrelizumab and 31% treated with natalizumab. Eighteen percent of ocrelizumab and 100% of natalizumab patients had a positive antibody response. In ocrelizumab-treated patients, there was no correlation between age, sex, BMI, total number of infusions, immunoglobulin G, CD19, or absolute lymphocyte count and antibody response. There was a trend suggesting that a longer interval between the last infusion and vaccination increased the likelihood of producing antibodies (P = 0.062). All ocrelizumab patients with negative antibody responses had positive T-cell responses. Conclusions Treatment with ocrelizumab substantially impaired the humoral response to SAR-CoV-2 vaccination but did not impair T-cell responses. Further research is needed to determine if the T-cell response to SARS-CoV-2 vaccination is sufficient to prevent infection or reduce severity of COVID in patients who did not produce antibodies.
Self-Organization and Complexity in Evolutionary Theory, or, in this Life the Bread Always Falls Jammy Side Down

Let it be borne in mind in what an endless number of strange peculiarities our domestic productions, and, in a lesser degree, those under nature, vary; and how strong the hereditary tendency is. Under domestication, it may be truly said that the whole organization becomes in some degree plastic. Let it be borne in mind how infinitely complex and close-fitting are the mutual relations of all organic beings to each other and to their physical conditions of life. Can it, then, be thought improbable, seeing that variations useful to man have undoubtedly occurred, that other variations useful in some way to each being in the great and complex battle of life, should sometimes occur in the course of thousands of generations? If such do occur, can we doubt (remembering that many more individuals are born than can possibly survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind? On the other hand we may feel sure that any variation in the least degree injurious would be rigidly destroyed. This preservation of favourable variations and the rejection of injurious variations, I call Natural Selection. (Charles Darwin, Origin of Species, 80–81)
Capsule Commentary on Haas et al., Provider Attitudes and Screening Practices Following Changes in Breast and Cervical Cancer Screening Guidelines.

T he most recent U.S. Preventive Services Task Force (USPSTF) recommendations call for a reduction in the frequency of and eligible age ranges for breast cancer (2009) and cervical cancer screening (2012). These changes have stirred controversy over care rationing and resulted in additional complexity for primary care providers. In this issue of JGIM, Haas et al. present a timely assessment of provider self-reported attitudes and practice changes toward breast and cervical cancer screening following the latest USPSTF recommendations.While cancer screening is critical to public health, overuse of screening is costly to the healthcare system and consumes scarce resources. Haas et al. found that providers prescribed more screening than that endorsed in USPSTF guidelines, especially for breast cancer, and cited patient concerns as the primary barrier to concordance with the recommendations. Provider disagreement with the recommendations and health system measurement of provider screening practices that use conflicting measurement criteria were also common barriers. Cancer screening in excess of the latest guideline recommendations comes as no surprise, given thatMedicare coverage for cancer screening has become more generous during the same time period, leading to elimination of cost-sharing requirements. The study sample was not nationally representative, and preliminary reports suggest that nationwide mammography rates may have decreased in response to the 2009 USPSTF revision. However, findings for breast screening were consistent with prior surveys of cancer screening practices among primary care providers. Haas et al. expanded their sample beyond physicians to include nurse practitioners, certified nurse midwives, and physician assistants, and theirs is the first study to observe self-reported cervical cancer screening practices in light of the 2012 changes in cervical screening recommendations. Provider self-reports alone may be insufficient for evaluating the discussion that occurs between providers and their patients around cancer screening. Screening decisions are complex and are influenced by patientlevel factors and patient–provider communication, and these complex interactions should be considered in the design of future studies. For example, many women may be accustomed to cancer screening at regular intervals, and screening cessation in concordance with guidelines may be viewed as a major decision.
The Eighth Amendment and Prisoners' Rights: A Summary of Post-Campbell and Jackson Jurisprudence

This brief paper was written for the William B. Bryant Inn of Court's February 2010 meeting. The Inn's theme for the 2009-2010 term was a review of some of the wide array of landmark cases that Judge Bryant either litigated as an attorney or presided over as a judge.Chief Judge Bryant’s 1975 and 1976 decisions in Campbell v. McGruder and Inmates of DC Jail v. Jackson were the first in a series of cases that addressed DC prisoners’ complaints alleging Eighth Amendment violations of the protection against cruel and unusual punishment. This paper summarizes the developments in this area of law in the District of Columbia since those decisions.
Are You Trying Too Hard

Everyone makes mistakes. It’s part of what makes us human. Because humans understand their actions are sometimes flawed, it was perhaps inevitable that the field of psychology developed a rich body of academic literature to describe why it is that human beings often make poor decisions. Although insights from academia can be highly theoretical, our everyday life experiences corroborate many of these findings at a basic level: “I know I shouldn’t eat the McDonalds BigMac, but it tastes so good.” Because we recognize our frequent irrational urges, we often seek the judgment of experts, to avoid becoming our own worst enemy. We assume that experts, with years of experience in their particular fields, are better equipped and incentivized to make unbiased decisions. But is this assumption valid? A surprisingly robust, but neglected branch of academic literature, has studied the assumption that experts make unbiased decisions for over 60 years. The evidence tells a decidedly one-sided story: systematic decision-making, through the use of simple quantitative models with limited inputs, outperforms discretionary decisions made by experts. This essay summarizes research related to the “models versus experts” debate and highlights its application in the context of investment decision-making. Based on the evidence, investors should de-emphasize their reliance on discretionary experts, and should instead approach investment decisions with systematic models. To quote Paul Meehl, an eminent scholar in the field, “There is no controversy in social science that shows such a large body of qualitatively diverse studies coming out so uniformly in the same direction as this one [models outperform experts].”
Imagining, Becoming, and Being a Teacher: How professional history mediates teacher educator identity

This is a self-study wherein we, two teacher educators who are both former public school elementary-grade teachers, sought increased understanding of our professional identities as teachers. We asked, “How is the professional identity of teacher educators mediated by their prior experience as teachers?” We independently created retrospective narratives of our teaching histories, recording key events in our development as teachers and teacher educators. We read and reread these narratives, identified categories and perspectives that cut across them, coded the data, and formulated a descriptive picture of our experiences. We also shared our analysis with a critical friend at several stages of the analysis. The process revealed stories of imagining ourselves as teachers, becoming teachers, and being teachers. Our study shows that fundamental aspects of our teacher identities have remained constant as our careers have evolved. Regardless of the setting, the age of our students, or the expanded expectations to...
Characterization of free radical generation by xanthine oxidase. Evidence for hydroxyl radical generation.

Xanthine oxidase has been hypothesized to be an important source of biological free radical generation. The enzyme generates the superoxide radical, •O2− and has been widely applied as a •O2− generating system; however, the enzyme may also generate other forms of reduced oxygen. We have applied electron paramagnetic resonance (EPR) spectroscopy using the spin trap 5,5′-dimethyl-1-pyrroline-N-oxide (DMPO) to characterize the different radical species generated by xanthine oxidase along with the mechanisms of their generation. Upon reaction of xanthine with xanthine oxidase equilibrated with air, both DMPO-OOH and DMPO-OH radicals are observed. In the presence of ethanol or dimethyl sulfoxide, α-hydroxyethyl or methyl radicals are generated, respectively, indicating that significant DMPO-OH generation occurred directly from OH rather than simply from the breakdown of DMPO-OOH. Superoxide dismutase totally scavenged the DMPO-OOH signal but not the DMPO-OH signal suggesting that •O2− was not required for •OH generation. Catalase markedly decreased the DMPO-OH signal, while superoxide dismutase + catalase totally scavenged all radical generation. Thus, xanthine oxidase generates •OH via the reduction of O2 to H2O2, which in turn is reduced to •OH. In anaerobic preparations, the enzyme reduces H2O2 to •OH as evidenced by the appearance of a pure DMPO-OH signal. The presence of the flavin in the enzyme is required for both •O2− and •OH generation confirming that the flavin is the site of O2 reduction. The ratio of •O2− and •OH generation was affected by the relative concentrations of dissolved O2 and H2O2. Thus, xanthine oxidase can generate the highly reactive •OH radical as well as the less reactive •O2− radical. The direct production of •OH by xanthine oxidase in cells and tissues containing this enzyme could explain the presence of oxidative cellular damage which is not prevented by superoxide dismutase.
Value of Children, Child Labor, and Fertility Preferences in Urban Nigeria

This paper examines the value of children as perceived by parents and explores the link between child labor and fertility preferences in urban Nigeria. We provide a unique perspective to utilize the Caldwell’s Wealth Flow Theory by considering the connection between current economic benefit of children and parent’s fertility intentions. This is a departure from previous studies that tend to relate future benefit of children at parent’s old age to current or future fertility behavior. Findings indicate that sons are valued for their future patriarchal status and their kinship role in continuing the family name. Daughters are more likely than sons to be relied upon for financial support at old age, and are cherished for their potential roles as future mothers. The results also suggest that labor contribution of children has become a central part of the fertility equation in urban areas. Indeed, a significant proportion of parents had children because of expected labor contribution of those children. Parents wanted more children because of the financial support of current children. Others would expect additional children yet to be born to contribute to the household income. Findings have implications for regulating child labor and fertility in Nigeria.
Prostate carcinoma with testicular or penile metastases: Clinical, pathologic, and immunohistochemical features

BACKGROUND Despite the proximity, prostate carcinoma seldom metastasizes to the penis or testis. METHODS In the current study, the authors retrospectively examined the clinical history of 12 patients with prostate carcinoma and testicular or penile metastases. Pathologic review and immunohistochemical staining were performed on tumors from eight of these patients. RESULTS Patients with prostate carcinoma and testicular or penile metastasis responded to androgen ablative therapy (median duration, 33 months). They were predisposed to developing persistent or recurrent urinary symptoms and visceral metastases. Six of 9 evaluable patients had elevated serum carcinoembryonic antigen levels (> 6 ng/mL), whereas 2 of 10 patients had low or undetectable serum prostate specific antigen levels (< 4 ng/mL). In seven of the eight patients for whom specimens were available, the tumors were found to contain histologic features that were compatible with a diagnosis of ductal or endometrioid adenocarcinoma of the prostate. CONCLUSIONS Patients with prostate carcinoma and testicular or penile metastases have unique clinical and pathologic characteristics. Many of these patients' tumors are compatible with a subtype of prostate carcinoma known as ductal adenocarcinoma. Further studies need to be performed to elucidate the biologic basis of the various histologic subtypes of prostate carcinoma. Cancer 2002;94:2610–7. © 2002 American Cancer Society. DOI 10.1002/cncr.10546
Performance of NLMS

This chapter contains sections titled: Separation Principle Simulation Results Appendix: Relating NLMS to LMS
Charge transfer and energy transfer analysis of battery charge equalization

Cell charge imbalance is a very common issue in the battery system, which can cause efficiency and even safety problems. To solve this issue, many types of battery charge equalizers have been designed. In this extended abstract, we will focus on the analysis of charge transfer and energy transfer in the battery charge equalization process. These analysis results can help evaluate equalization performance and design efficient equalization system.
Anatomy: Head, Thorax, Abdomen, and Genitalia

Publisher Summary This chapter focuses on the anatomical structures of the three major tagmata of the insect body: head, thorax, and abdomen, and on the external genitalia. It also provides a hypothetical ground plan for major structures, followed by themes in anatomical variation based on adaptation observed in the Insecta . Description of the relative placement of anatomical features is critical element in the study of anatomical structure because relative position is one of the three basic tenets of homology, including size, shape, and embryology. Upon casual observation, the size of any given insect's head appears to be in proportion to the size of its body. The head in anatomical nomenclature provides some of the best examples of evolutionary trends in anatomy. The thorax represents the second tagma of the insect body. Functional role of the thorax has always been locomotion, since the primary modifications of the thorax have been for locomotion. The abdomen is more conspicuously segmented than either the head or the thorax. The abdomen is the least specialized of the body tagma, but there are notable exceptions such as the scale insects. The examination of the reproductive anatomy of different insect orders helps to develop an appreciation for the evolutionary trends in the formation of the external genitalia. Morphology is concerned with the form and function of anatomical structure; because anatomy is an expression of organic evolution, morphology seeks to investigate possible explanations for organic diversification observed in nature.
Role of topography in facilitating coexistence of trees and grasses within savannas

[1] The factors and processes that may explain the observed coexistence of trees and grasses in savannas are not well understood. Here we propose a new hypothesis that addresses this issue. We hypothesize that “variations in elevation at relatively short horizontal scales of ∼1 km force similar variations in soil moisture and thus create significantly different hydrologic niches within any large area. Under water-limited conditions the relatively wet valleys favor trees, while the relatively dry hills favor grasses. This coexistence of trees and grasses is only possible for a window of climatic conditions that are characteristic of savannas.” To test this hypothesis, numerical simulations are performed for the region of West Africa using a model that simulates vegetation dynamics, the Integrated Biosphere Simulator (IBIS), and a distributed hydrologic model, Systeme Hydrologique Europeen (SHE). IBIS is modified to include the groundwater table (GWT) as a lower boundary. The spatial distribution of GWT is simulated by SHE. At 9°N the model simulates trees even when the GWT is assumed to be infinitely deep; at 13°N the model simulates grasses even when the capillary fringe of the GWT reaches the surface. However, for the transitional climate, at 11°N, trees are simulated when the GWT is at ∼2.5 m from the surface, but grasses are simulated when the GWT is deeper than 2.5 m. These results suggest that the variability of soil moisture forced by topography can be a determinant factor of vegetation distribution within savannas. Furthermore, they confirm that this role of topography can be significant only in a certain climatic window characteristic of savannas.
Lyman α radiative transfer in a multiphase medium

Hydrogen Lyman a (Lya) is our primary emission-line window into high-redshift galaxies. Despite an extensive literature, Lya radiative transfer in the most realistic case of a dusty, multiphase medium has received surprisingly little detailed theoretical attention. We investigate Lya resonant scattering through an ensemble of dusty, moving, optically thick gas clumps. We treat each clump as a scattering particle and use Monte Carlo simulations of surface scattering to quantify continuum and Lya surface scattering angles, absorption probabilities, and frequency redistribution, as a function of the gas dust content. This atomistic approach speeds up the simulations by many orders of magnitude, making possible calculations which are otherwise intractable. Our fitting formulae can be readily adapted for fast radiative transfer in numerical simulations. With these surface scattering results, we develop an analytic framework for estimating escape fractions and line widths as a function of gas geometry, motion, and dust content. Our simple analytic model shows good agreement with full Monte Carlo simulations. We show that the key geometric parameter is the average number of surface scatters for escape in the absence of absorption, N 0 , and we provide fitting formulae for several geometries of astrophysical interest. We consider the following two interesting applications. (i) Equivalent widths (EWs). Lya can preferentially escape from a dusty multiphase interstellar medium if most of the dust lies in cold neutral clouds, which Lya photons cannot penetrate. This might explain the anomalously high EWs sometimes seen in high-redshift/submillimetre sources. (ii) Multiphase galactic outflows. We show the characteristic profile is asymmetric with a broad red tail, and relate the profile features to the outflow speed and gas geometry. Many future applications are envisaged.
Professionalism and Archivists in the United States

Since the formation of the Conference of Archivists in 1909, archivists in the United States have been concerned with their own professional status and standards. Although archivists have made tremendous strides in the development of professionalism, especially over the past decade, recent self-assessments reveal that their profession still has serious deficiencies. This essay, using sociological models and examples of other professions, attempts to analyze some of the reasons for these problems and suggests an agenda of issues for archivists' consideration. The article discusses society's image of the archivist and its understanding of the archival mission, archivists' need to develop a stronger national voice, problems with archival education, the purpose of individual certification and institutional accreditation, and the need for archivists to acquire a broader notion of their own potential. While an improved professionalism is not the only solution to the problems archivists face, it is certainly a m...
Asymptotic formulation of a differentially rotating star with small dissipation

A system of nonlinear differential equations is formulated for a differentially rotating star with a small radiative dissipation. Certain dimensionless parameters are introduced, such as e1 to indicate the degree of small, but not necessarily infinitesimal, departure from the steady, axisymmetric stage, and e2 to indicate the localization of perturbations etc. As examples of application, the Goldreich-Schubert and the Solberg-Hoiland instabilities are discussed.
Visual crowd surveillance is like hydrodynamics

Video Surveillance and Monitoring is very active area of research in Computer Vision. However, most of the current approaches assume that the observed scene is not crowded, and that reliable tracks of objects are available over longer durations. Therefore, these approaches are not extendable to more challenging surveillance videos of crowded environments like markets, subways, religious festivals, parades, concerts, football matches etc, where tracking of individual objects is very hard, if not impossible. We have proposed a framework, which views the flow of a high density crowd like the flow of a liquid, prompting the use of ideas and techniques often found in the study of hydrodynamics. Therefore, we treat interactions of people in the scene like moving particles in a liquid on three different length scales (macroscopic, mesoscopic, and microscopic); each scale corresponding to one of the three problems: tracking individuals, detection of abnormal behaviors, and segmentation of crowd motion.
The effect of orientation on the morphology and kinetics of solvent crazing in polystyrene

Unoriented, uniaxially oriented, and biaxially oriented polystyrene films were crazed by immersing samples in liquid n-hexane at 45°C. The craze morphology and crazing kinetics were studied as a function of the preorientation and thermal histories of the polymer films. The shape of the micropores was related to the degree of orientation of the film. Ellipsoidal microvoids were formed on the surfaces of uniaxially oriented films containing a residual glassy core. Unoriented samples displayed spherical microvoids 0.1 to 3 μ in diameter. The major-to-minor axis ratio of the micropores increased monotonically from 1/1 to 10/1 as the sample orientation was increased from 0% to 200%. The kinetics of the crazing process similarly increased with uniaxial orientation. Surfaces of unannealed films which crazed mainly during the sorption of liquid n-hexane displayed numerous micropores when examined by the SEM. Conversely, films which were extensively annealed crazed mainly during desorption regardless of subsequent orientation. These extensively annealed films exhibited surfaces with many fine cracks and few, if any, micropores.
The Eclipsing Binary RU Eridani

RU Eri is a near-contact eclipsing binary (V ≈ 9.24 magV) with a 0.632-day orbital period. The Wilson-Devinney program is used to simultaneously solve new UBVUBV light curves obtained between 1973 and 1981 at the Fernbank Science Center Observatory, together with existing single-lined radial velocity measurements. Light and velocity solution parameters, orbital elements, and absolute dimensions are presented. We find the more massive component to fill its Roche lobe completely, while the less massive star nearly fills its limiting lobe (98% by radius), making RU Eri a near-contact or broken-contact system. Thermal contact between the two stars is also broken, as indicated by the large temperature difference between the two components (≈1800 K). We present masses and radii for the two stars for a range of adopted masses for the primary component. The absolute dimensions imply a distance greater than 190 pc. New ephemerides are computed from published eclipse timings, including 13 new minima determined from our observations.
Regional variation in rat aortic endothelial surface morphology: Relationship to regional aortic permeability☆

Abstract The regional variation of rat aortic lumenal surface topography has been examined by employing techniques of scanning electron microscopy. This study was undertaken in an attempt to gain additional insight into the current controversy regarding endothelial folds and cross bridges and their possible role with respect to regulation of vessel transmural permeability. Within the ascending aorta, aortic arch, and upper third of the thoracic aorta distinct, prominent endothelial folds connected by interlinking cross bridges were easily identifiable. The middle third of the thoracic aorta contained less prominent endothelial folds; photomicrographs from these regions consistently failed to reveal the presence of any interfold cross bridges. In the lower third of the thoracic aorta, endothelial folds were notably lacking. These differences in regional aortic surface topography have been discussed in light of known regional differences in aortic wall permeability and with respect to regional differences in apearance of endothelial silver-staining lines.
Reciprocal Behaviour Associated with Altered Homeostasis and Photosensitivity of Drosophila Clock Mutants

The circadian oscillators of genetically short-period and long-period Drosophila exhibit reciprocal behaviour in four distinct ways: (1) with respect to the dependence of period on temperature, (2) in the change of period during constant darkness after ten days of constant light, (3) in the change of period during the second ten days of darkness as compared with the period during the first ten days, and (4) in the period change resulting from exposure to low-intensity constant light. The homeostatic control of the dependence of period length on temperature is impaired in the mutants as compared with wild-type flies. The normal Drosophila pacemaker may comprise two mutually coupled oscillators, whereas the mutants may represent a reduction in activity of one or the other constituent oscillator.
A Semi-Lagrangian Spectral Algorithm for Pollutant Transport and Diffusion Studies

Abstract A semi-Lagrangian model was developed based on the atmospheric transport-diffusion equation, employing the semi-Lagrangian technique incorporated with the spectral method. The numerical algorithms of the semi-Lagrangian technique and the spectral method for solving the transport-diffusion equation, subjected to boundary conditions, are described. The model simulated the transport and diffusion of pollutants from an elevated point source. The accuracy of the algorithms was revealed by numerical tests compared with analytical solutions in cases of simple profiles of the mean wind and the eddy diffusivity. To demonstrate the feasibility of the algorithms for studying air pollution in the atmospheric boundary layer, the model, using realistic profiles of the mean wind and the eddy diffusivity, simulated the distributions of pollutant concentrations under various atmospheric stabilities. As will be shown, the algorithms are capable of producing excellent results, making them attractive and promising f...
Enhancing online timeline visualizations with events and images

The use of timeline to visualize time-series data is one of the most intuitive and commonly used methods, and is used for widely-used applications such as stock market data visualization, and tracking of poll data of election candidates over time. While useful, these timeline visualizations are lacking in contextual information of events which are related or cause changes in the data. We have developed a system that enhances timeline visualization with display of relevant news events and their corresponding images, so that users can not only see the changes in the data, but also understand the reasons behind the changes. We have also conducted a user study to test the effectiveness of our ideas.
The Art of Change: The Impact of Place and the Future of Academic Art Library Collections.

Academic institutions have long supported stand-alone branch libraries devoted to fine arts, architecture, and other allied fields. As subject specific collecting on campuses has been decentralized by collaborative collection development, consortial borrowing, and the quick availability of materials in both digital and print formats, the need for the physical space of the art library for research has diminished. The authors, both of whom are in administrative positions at ARL art libraries, explore how collections are directly tied to use of space in architecturally significant spaces and conclude by offering suggestions how space can help heighten collections access and emulate greater value on their campuses.
TULA-family proteins: an odd couple

Two members of the TULA family (TULA/STS-2/UBASH3A and TULA-2/STS-1/UBASH3B) recently emerged as novel regulators of several cellular functions. The degree of structural similarity between the TULA-family proteins is typical for proteins that belong to the same family. Furthermore, the experiments with knockout mice lacking these proteins may be interpreted as suggesting that functions of TULA-family proteins in T lymphocytes overlap. At the same time, TULA and TULA-2 exhibit clear functional dissimilarities, starting with the finding that a conserved phosphatase domain present in both proteins exhibits remarkable differences in enzymatic activity; TULA-2 is an active phosphatase capable of dephosphorylating multiple tyrosine-phosphorylated proteins, whereas the phosphatase activity of TULA is extremely low. In contrast, TULA, but not TULA-2, facilitates growth factor withdrawal-induced apoptosis in T cells. In spite of their apparent importance, the functional role of TULA-family proteins is not well understood. In particular, the role of functional dissimilarities between them remains unclear.
What Beauty Promises:Reflections on Alexander Nehamas, Only a Promise of Happiness: The Place of Beauty in a World of Art

Alexander Nehamas calls beauty a 'promise of happiness' and claims that it is an object of love. While this approach appealingly places beauty at the center of both artistic passion and everyday life, it also renders it riskily personal. This discussion raises two main questions to Nehamas. The first question regards the role of happiness in the concept of beauty, for many beautiful artworks seem to acknowledge the inevitability of sorrow rather than its opposite. The second question concerns how beauty may be both personal and grounded in factors sufficiently outside the self to safeguard it against the instability of individual preferences. To explore the latter issue, Nehamas's ideas are compared to those of another Platonist, Iris Murdoch.
Developmental pattern of expression of BMP receptors and Smads and activation of Smad1 and Smad5 by BMP9 in mouse basal forebrain

Basal forebrain cholinergic neurons play critical roles in the organization of brain cortical structures and in processes such as learning and memory. We have previously shown that bone morphogenetic protein (BMP) 9, a member of the transforming growth factor (TGF) beta superfamily of cytokines, is a differentiating factor for cholinergic central nervous system neurons. However, whereas the basic signal transduction pathways for most known members of the TGF-beta superfamily have been well characterized in brain and other organs, nothing is known about the signal transduction pathway of BMP9 in the brain. Here, we describe the pattern of expression of BMP receptors, including Bmpr-Ia, Bmpr-Ib, Bmpr-II, Actr-I. Actr-Ib, Actr-II and Actr-IIb, Alk-1, and Smad proteins (Smads 1-5 and Smad8) in the septal region of the basal forebrain during mouse development. Using cultured basal forebrain cells derived from embryonic day (E) 14 mice, we show that BMP9 causes phosphorylation of Smad1 and Smad5, formation of a complex of Smad4 with Samd1 and/or Smad5, and translocation of these proteins into the nucleus. These data show that BMP9 activates the canonical BMP signaling pathway and suggest that this could be one of the mechanisms responsible for the induction of the cholinergic phenotype by BMP9 in the basal forebrain.
Measurement of glucose and 2-deoxy-2-[18F]fluoro-D-glucose transport and phosphorylation rates in myocardium using dual-tracer kinetic experiments

Abstract To examine the use of 2-deoxy-2-[ 18 F]fluoro-D-glucose (2-FDG) as a glucose analog for measuring glucose utilization rate in myocardium, dual-tracer kinetic experiments with 2-FDG and 2-[ 3 H]glucose were performed in the perfused, isolated rabbit interventricular septum to measure simultaneously the transport and phosphorylation rates of glucose and 2-FDG. Results of the present study indicated that, in the septum, (i) the transport rate constants of 2-FDG and glucose were similar in magnitude, (ii) the phosphorylation rate constant for 2-FDG was about 60% of that of glucose, (iii) hypoxia caused an increase in phosphorylation rates of glucose and 2-FDG without affecting transport.
Adolescent Cocaine Use: Epidemiology, Risk Factors, and Prevention

Epidemiological studies of adolescent cocaine use are critically reviewed, risk factors for use are identified, and implications for prevention are discussed. Cocaine use among adolescents is incre...
Vibrational relaxation rates in the direct simulation Monte Carlo method

Exact relationship is developed that connects the vibrational relaxation number, ZvDSMC, used in the direct simulation Monte Carlo method and that employed in continuum simulations. An approximate expression for ZvDSMC is also derived that is cost-effective and applicable when translational temperature is larger than vibrational temperature.