cssi/SciSciGPT-SciSciNet huggingface dataset:
Hierarchical density-based cluster analysis framework for atom probe tomography data.

Abstract Atom probe tomography (APT) has enabled the direct visualization of solute clusters. However one of the main analysis methods used by the APT community, i.e. the maximum separation method, often suffers from subjective parametric selection and limited applicability. To address the need for more robust and versatile analysis tools, a framework based on hierarchical density-based cluster analysis is implemented. Cluster analysis begins with the HDBSCAN algorithm to conservatively segment the datasets into regions containing clusters and a matrix or noise region. The stability of each cluster and the probability that an atom belongs to a cluster are quantified. Each clustered region is further analyzed by the DeBaCl algorithm to separate and refine clusters present in the sub-volumes. Finally, the k-nearest neighbor algorithm may be used to re-assign matrix atoms to clusters, based on their probability values. Four mandatory parameters are required for this cluster analysis approach. However, the selection of an appropriate value for only one of these parameters, i.e. a rough estimate of the minimum cluster size, is essential. The improved performance of the method was evaluated by analyzing four synthetic APT datasets and comparing the outcome with the commonly-used maximum separation method. Codes and data are made available through GitHub.
A statistical analysis of the elastic distortion and dislocation density fields in deformed crystals

Abstract The statistical properties of the elastic distortion fields of dislocations in deforming crystals are investigated using the method of discrete dislocation dynamics to simulate dislocation structures and dislocation density evolution under tensile loading. Probability distribution functions (PDF) and pair correlation functions (PCF) of the simulated internal elastic strains and lattice rotations are generated for tensile strain levels up to 0.85%. The PDFs of simulated lattice rotation are compared with sub-micrometer resolution three-dimensional X-ray microscopy measurements of rotation magnitudes and deformation length scales in 1.0% and 2.3% compression strained Cu single crystals to explore the linkage between experiment and the theoretical analysis. The statistical properties of the deformation simulations are analyzed through determinations of the Nye and Kroner dislocation density tensors. The significance of the magnitudes and the length scales of the elastic strain and the rotation parts of dislocation density tensors are demonstrated, and their relevance to understanding the fundamental aspects of deformation is discussed.
Three-Dimensional Structure of Transfer RNA

Publisher Summary This chapter describes that one of the most interesting aspects of transfer RNA (tRNA) is its common “substrate” for many enzymes involved in protein synthesis, a process in which tRNA plays a key role in transmitting the genetic information from nucleic acids to proteins. Almost nothing is known about the mode of interaction by which tRNA is specifically recognized by more than a dozen different proteins in the protein-synthesizing system. Transfer RNA also interacts with messenger RNA and possibly with ribosomal RNA. To understand these highly specific protein-nucleic acid and nucleic acid-nucleic acid interactions, it is imperative to know the three-dimensional (3-D) structure of tRNA. It is likely that there are some conformational changes occurring during the recognition process by the various enzymes and nucleic acids. The starting point of the studies of these specific interactions with tRNA is a well-defined 3-D structure of tRNA. The chapter describes that significant progress has ‘been made in the determination of the 3-D structure of tRNA. The chapter focuses primarily on the structural features of tRNA, their correlation with the various experimental results, and functional implications.
Home environments of mothers with mental retardation

A prospective study of 38 mothers with IQs less than 75 and 27 mothers with IQs over 85 who were also low income was conducted. This study was designed to distinguish between children's developmental risk associated with maternal disability and risk related primarily to poverty. Findings from administration of the HOME inventory showed that mothers with intellectual limitations had significantly lower scores, indicating greater developmental risk for their children due to environmental deprivation. Most of the variance between groups was found on the interaction subscale. This suggests that strategies focused on interaction will be beneficial in assisting mothers with intellectual limitations in raising their children.
Simpson’s type inequalities for η-convex functions via k-Riemann–Liouville fractional integrals

We introduce some Simpson's type integral inequalities via k-Riemann–Liouville fractional integrals for functions whose derivatives are η-convex. These results generalize some results in the literature.
Race, Ethnicity, Socioeconomic Status, and Chronic Lung Disease in the U.S.

Background: Higher socioeconomic status (SES) indicators such as educational attainment and income reduce the risk of chronic lung diseases (CLDs) such as Chronic Obstructive Pulmonary Disease (COPD), emphysema, chronic bronchitis, and asthma. Marginalization-related Diminished Returns (MDRs) refer to smaller health benefits of high SES for marginalized populations such as racial and ethnic minorities compared to the socially privileged groups such as non-Hispanic Whites. It is still unknown, however, if MDRs also apply to the effects of education and income on CLDs. Purpose: Using a nationally representative sample, the current study explored racial and ethnic variation in the associations between educational attainment and income and CLDs among American adults. Methods: In this study, we analyzed data (n = 25,659) from a nationally representative survey of American adults in 2013 and 2014. Wave one of the Population Assessment of Tobacco and Health (PATH)-Adult study was used. The independent variables were educational attainment (less than high school = 1, high school graduate = 2, and college graduate = 3) and income (living out of poverty = 1, living in poverty = 0). The dependent variable was any CLDs (i.e., COPD, emphysema, chronic bronchitis, and asthma). Age, gender, employment, and region were the covariates. Race and ethnicity were the moderators. Logistic regressions were fitted to analyze the data. Results: Individuals with higher educational attainment and those with higher income (who lived out of poverty) had lower odds of CLDs. Race and ethnicity showed statistically significant interactions with educational attainment and income, suggesting that the protective effects of high education and income on reducing odds of CLDs were smaller for Blacks and Hispanics than for non-Hispanic Whites. Conclusions: Education and income better reduce the risk of CLDs among Whites than Hispanics and Blacks. That means we should expect disproportionately higher than expected risk of CLDs in Hispanics and Blacks with high SES. Future research should test if high levels of environmental risk factors contribute to the high risk of CLDs in high income and highly educated Black and Hispanic Americans. Policy makers should not reduce health inequalities to SES gaps because disparities sustain across SES levels, with high SES Blacks and Hispanics remaining at risk of health problems.
Finding a Sense of Community in Youth Soccer: A Composite Vignette of the Refugee Experience

This study examines the experience of a sense of community (SOC) for youth refugees in a community soccer club. Eleven male participants on a team for youth refugees participated in the study. Data collection was guided by a photo elicitation activity followed by semi-structured interviews. Both thematic analysis and creative nonfiction were employed to develop findings and present a composite vignette that strives to provide findings that are accessible, provocative, and give privilege to the voice of the participants. Most notably, findings provide support for two prominent theories of SOC within this context, and highlight the importance of emotional safety, shared history, leaders as role models, gratitude, and fun. The use of the vignette to present findings provides results in a format that is both accessible to practitioners and maintains the voice of the youth participants. The National Recreation and Park Association recently identified services for immigrants and refugees as key focus areas (NRPA, 2018). Findings from this study led to practical implications that address this focus area. Broadly, sport programs may provide a valuable venue for the development of protective factors such as a SOC for youth refugees. Further, teams that are specifically for refugees help facilitate the emotional safety and shared history necessary for the development of a SOC. Findings also suggest that refugees face numerous additional barriers that may require additional financial and practical support, including transportation or assistance with finding part-time employment. As such, managers may wish to consider building programs that follow a sport plus model that assists participants in other areas of life. Finally, findings point to ancillary social spaces that provide emotional safety as key parts of the experience. This also suggests the need to develop programs that leverage the common interests of sport into other social areas that provide additional benefits. Subscribe to JPRA
Good Relationships With Parents During Childhood as Buffers of the Association Between Childhood Disadvantage and Adult Susceptibility to the Common Cold.

OBJECTIVE Children reared by parents of low socioeconomic status (SES) go on to have elevated rates of physical health problems and premature mortality. However, many children reared in low-SES families remain healthy throughout the life-span. Here, secondary analyses of archival data tested the hypothesis that a positive relationship with parents during childhood acts as a buffer of the increased risk of adult susceptibility to infectious illness associated with low childhood SES. METHODS One hundred seventy-six healthy adults reported their childhood SES and the quality of their relationships with their parents during childhood. Relationship quality was defined as parental care, love and support, lack of conflict with parents, and family cohesiveness. Afterward, participants were exposed to a respiratory virus and monitored in quarantine for 5 days for the development of a "common cold" as indicated by infection and objective markers of illness. RESULTS The increased risk of developing a cold associated with being reared in a low SES household was attenuated by a positive relationship with parents during childhood (b(SE) = 0.08 (0.03), p = .010). This buffering of disease risk held up across the four components of relationship quality (p values < .05). The association was independent of adult SES, demographics, prechallenge immunity to the virus, current levels of neuroticism and stress, parental divorce during childhood, and number of siblings (p values < .05). CONCLUSIONS Individuals with positive relationships with their parents during childhood are buffered from the increased risk of adult susceptibility to an infectious disease associated with low childhood SES.
Capitalism and nationalism in the longue durée: Hegemony, crisis, and state-seeking nationalist mobilization, 1492–2013:

This article analyzes the historical dynamics of state-seeking nationalism from 1492 to 2013. By synthesizing Gramsci’s insights of hegemony with world-systems perspective and historical institutio...
Nonthermally dominated electron acceleration during magnetic reconnection in a low-β plasma

By means of fully kinetic simulations, we investigate electron acceleration during magnetic reconnection in a nonrelativistic proton–electron plasma with conditions similar to solar corona and flares. We demonstrate that reconnection leads to a nonthermally dominated electron acceleration with a power-law energy distribution in the nonrelativistic low-β regime but not in the high-β regime, where β is the ratio of the plasma thermal pressure and the magnetic pressure. The accelerated electrons contain most of the dissipated magnetic energy in the low-β regime. A guiding-center current description is used to reveal the role of electron drift motions during the bulk nonthermal energization. We find that the main acceleration mechanism is a Fermi-type acceleration accomplished by the particle curvature drift motion along the electric field induced by the reconnection outflows. Although the acceleration mechanism is similar for different plasma β, low-β reconnection drives fast acceleration on Alfvenic timescales and develops power laws out of thermal distribution. Thus, the nonthermally dominated acceleration resulting from magnetic reconnection in low-β plasma may have strong implications for the highly efficient electron acceleration in solar flares and other astrophysical systems.
Backhauling Many Devices: Relay Schemes for Massive Random Access Networks

The number of devices connected to Internet of Things (IoT) and massive machine-type communication (mMTC) networks is expected to increase exponentially in the next generation of wireless communication systems, resulting in a new type of “massive” random access network. However, most of the work in this emerging field considers the single-hop setting with direct communication between the users and a fully-equipped base station. In contrast, this work explores the massive random access problem in a two-hop relay setting where users access the network through a femto- or pico-cell relay which itself only has a limited amount of bandwidth/power. We present two low-complexity relaying schemes designed to minimize power consumption and discuss their tradeoffs using numerical simulations.
Vitamin D Level Stability in Dystrophinopathy Patients on Vitamin D Supplementation.

BACKGROUND Expert guidelines recommend annual monitoring of 25-hydroxyvitamin D (25-OHD) and maintaining 25-OHD ≥30 ng/ml in patients with dystrophinopathies. OBJECTIVE We hypothesized that 25-OHD remains stable and requires less frequent monitoring in patients taking stable maintenance doses of vitamin D. METHODS We performed a retrospective cohort study, using the electronic health record to identify 26 patients with dystrophinopathies with a baseline 25-OHD ≥30 ng/mL and at least one additional 25-OHD measurement. These patients had received a stable dose of vitamin D for ≥3 months prior to their baseline 25-OHD measurement and throughout follow-up. The main outcome measured was the mean duration time the subjects spent with a 25-OHD ≥30 ng/mL. RESULTS Only 19% of patients dropped their 25-OHD to < 30 ng/ml, with a mean time to drop of 33 months and a median nadir 25-OHD of 28 ng/mL. CONCLUSIONS These results suggest that measurement of 25-OHD every 2-2.5 years may be sufficient in patients with a baseline 25-OHD ≥30 ng/mL and who are on a stable maintenance dose of vitamin D. Other patients may require more frequent assessments.
Promoting Permanency and Human Rights

An increasing number of children are being cared for exclusively by grandparents or extended family. The majority of these caregivers are raising children outside of the foster care system without a formal legal status. In fact, kinship diversion, placing children whose parents cannot or will not care for them with family or friends outside of the foster care system, is encouraged by state and federal law. Informal kinship caregivers face many obstacles to providing care for children and they are more likely to be unemployed, receive government benefits, and be less educated, as compared with parents raising their own children. In addition, the majority of these caregivers live in poverty, and few receive adequate subsidies or other support for the children in their care. When an informal kinship caregiver living in poverty wishes to move for permanency, through adoption or permanent guardianship proceedings, the out-of-pocket expenses are an obstacle — the costs of a private adoption or permanent guardianship proceeding top $3,000, not including attorney’s fees. While adoptions and permanent guardianships are at least partially subsidized when the children are in foster care, the subsidies for these legal proceedings for informal kinship caregivers living in poverty are inadequate in many states. In those states, informal kinship caregivers living in poverty who wish to move for permanency for the children in their care are barred from doing so for lack of funds. Using a human rights lens to analyze the applicable law, regulations, and practices of all fifty states and the federal government, this article argues for the subsidization of private adoptions and permanent guardianships for kinship caregivers living in poverty.
Stay just a little bit longer

The short lifetime of light-induced superconductivity prevents the measurement of its transport properties. Encouraging this state to stay a little longer in K3C60 allows the observation of vanishing electrical resistance.
A Modeling and Machine Learning Pipeline to Rationally Design Treatments to Restore Neuroendocrine Disorders in Heterogeneous Individuals.

Heterogeneity among individual patients presents a fundamental challenge to effective treatment, since a treatment protocol working for a portion of the population often fails in others. We hypothesize that a computational pipeline integrating mathematical modelling and machine learning could be used to address this fundamental challenge and facilitate the optimization of individualized treatment protocols. We tested our hypothesis with the neuroendocrine systems controlled by the hypothalamic-pituitary-adrenal (HPA) axis. With a synergistic combination of mathematical modelling and machine learning (ML), this integrated computational pipeline could indeed efficiently reveal optimal treatment targets that significantly contribute to the effective treatment of heterogeneous individuals. What is more, the integrated pipeline also suggested quantitative information on how these key targets should be perturbed. Based on such ML revealed hints, mathematical modelling could be used to rationally design novel protocols and test their performances. We believe that this integrated computational pipeline, properly applied in combination with other computational, experimental and clinical research tools, can be used to design novel and improved treatment against a broad range of complex diseases.
Fitness Tracker Information and Privacy Management: Empirical Study

Background: Fitness trackers allow users to collect, manage, track, and monitor fitness-related activities, such as distance walked, calorie intake, sleep quality, and heart rate. Fitness trackers have become increasingly popular in the past decade. One in five Americans use a device or an app to track their fitness-related activities. These devices generate massive and important data that could help physicians make better assessments of their patients’ health if shared with health providers. This ultimately could lead to better health outcomes and perhaps even lower costs for patients. However, sharing personal fitness information with health care providers has drawbacks, mainly related to the risk of privacy loss and information misuse. Objective: This study investigates the influence of granting users granular privacy control on their willingness to share fitness information. Methods: The study used 270 valid responses collected from Mtrurkers through Amazon Mechanical Turk (MTurk). Participants were randomly assigned to one of two groups. The conceptual model was tested using structural equation modeling (SEM). The dependent variable was the intention to share fitness information. The independent variables were perceived risk, perceived benefits, and trust in the system. Results: SEM explained about 60% of the variance in the dependent variable. Three of the four hypotheses were supported. Perceived risk and trust in the system had a significant relationship with the dependent variable, while trust in the system was not significant. Conclusions: The findings show that people are willing to share their fitness information if they have granular privacy control. This study has practical and theoretical implications. It integrates communication privacy management (CPM) theory with the privacy calculus model.
“Package Deal”: The Curious Relationship Between Fiduciary Duties and the Implied Covenant of Good Faith and Fair Dealing in Delaware Limited Liability Companies

Since 1977, the popularity of the limited liability company (“LLC”) has grown tremendously, overtaking the corporation and the partnership as the preferred business structure in many jurisdictions. Amidst this growth in popularity, a legal debate has sparked concerning the existence, nature, and extent of the fiduciary and contractual duties owed in the LLC context. Drafters of LLC agreements can adjust fiduciary “norms” through limitation or, in certain jurisdictions like Delaware, through complete elimination of fiduciary duties. However, the implied contractual covenant of good faith and fair dealing (the “Implied Covenant” or the “Covenant”) remains and cannot be waived by the parties. This delicate balance between waivable duties and an unwaivable covenant begs two key questions: What, if any, is the relationship between fiduciary duties and the Implied Covenant, and where is the boundary between the two? Further, how is the scope of the Implied Covenant affected when an LLC agreement eliminates fiduciary duties? The answers to these questions are critical in separating permissible acts under an LLC agreement from acts giving rise to causes of action for breach of contract. The relationship between fiduciary duties and the Implied Covenant is marked by an inherent tension that the Delaware courts have yet to properly resolve. Rather, these courts have structured an extremely narrow view of the Covenant, and have sometimes conflated the Covenant with fiduciary duties, thereby reducing the effectiveness of the Covenant as an independent means of enforcing behavioral norms arising from contractual relationships. Consequently, parties to LLC agreements have been left to question whether the Implied Covenant has any significance independent of fiduciary duties. This Article attempts to shed light on this dilemma, but cautions that, in this unique context, protection under the Covenant appears to be illusory when fiduciary duties are no longer in play. * Associate (Corporate), Baker Botts L.L.P.; J.D., magna cum laude, University of Houston Law Center (2012); B.S., Economics and Political Science, summa cum laude, University of Houston (2009). Many thanks to Professor Douglas Moll for his invaluable insight and comments. Thanks also to the editors of the University of Miami Business Law Review for their efforts in preparing this Article for publication.
Pathways of Electron Transfer in Desulfovibrio

Sulfate reducing, bacteria of the genus Desulfovibrio conduct anaerobic respiration, conserving energy through oxidative phosphorylation in anaerobic sulfate reduction (1,2). The reduction of sulfate is mediated by an electron transport system composed of dehydrogenases, electron carriers, and a series of reductases (3,5). Some of the enzymes and electron carries involved are found exclusively in the membrane fraction although a great many are soluble.
Gene Therapy Enters Adolescence

The Development of Human Gene Therapy. Theodore Friedmann, Ed. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY, 1999. 743 pp. $134. ISBN 0-87969-528-5. The contributors, leaders in the field, provide a compendium of review articles that highlights significant recent advances and illuminates the remaining obstacles to the use of gene therapies in clinical practice.
A continuous Gaussian approximation to a nonparametric regression in two dimensions

Estimating the mean in a nonparametric regression on a two-dimensional regular grid of design points is asymptotically equivalent to estimating the drift of a continuous Gaussian process on the unit square. In particular, we provide a construction of a Brownian sheet process with a drift that is almost the mean function in the nonparametric regression. This can be used to apply estimation or testing procedures from the continuous process to the regression experiment as in Le Cam's theory of equivalent experiments. Our result is motivated by first looking at the amount of information lost in binning the data in a density estimation problem.
Is There Such a Thing as a Language

‘There is no such thing as a language,’ Donald Davidson tells us (‘A Nice Derangement of Epitaphs,’ in Ernest LePore, ed., Truth and Interpretation [Oxford: Basil Blackwell 1986] 433-46, 446). Though this is a startling claim in its own right, it seems especially puzzling coming from a leading theorizer about language. Over the years, Davidson’s important essays have sparked the hope that there is a route to a positive, nonskeptical theory of meaning for natural languages. This hope would seem to be dashed if there are no natural languages. Unless Davidson’s radical claim is a departure from his developed views, the Davidsonian program appears to have undermined itself. In a recent book, Donald Davidson’s Philosophy of Language: An Introduction (which Davidson has enthusiastically endorsed), Bjorn Ramberg promises to establish that Davidson's startling claim is not an aberration. Rather, it 'emerges as a natural development of his theory of meaning' (2). He reads the claim that there is no such thing as a language as the claim that the concept of a language has no useful theoretical role. Like the concepts of meaning and reference, it is a 'ghost of reification' which Davidson attempts to 'exorcise' from our philosophical thinking about linguistic communication. All three concepts can be seen as mere ladders to be kicked away once the edifice of a Davidsonian theory of linguistic communication is properly erected on the sole foundation of the concept of truth. The result, he assures us, ‘is not a theory which undercuts itself, but a comprehensive, coherent account of the phenomenon of linguistic communication’ (3).
On subsumption removal and on-the-fly CNF simplification

CNF Boolean formulas generated from resolution or solution enumeration often have much redundancy. Efficient algorithms are needed to simplify and compact such CNF formulas. In this paper, we present a novel algorithm to maintain a subsumption-free CNF clause database by efficiently detecting and removing subsumption as the clauses are being added. We then present an algorithm that compact CNF formula further by applying resolutions to make it Decremental Resolution Free. Our experimental evaluations show that these algorithms are efficient and effective in practice.
Your Brain on Facebook: Neuropsychological Associations with Social Versus other Media

We measured individuals’ mental associations between four types of media (books, television, social/Facebook, and general informational web pages) and relevant concepts (Addictive, Story, Interesting, Frivolous, Personal, and Useful) using three different measurements: a Likert scale questionnaire, a speeded Yes/No judgment task, and electrical brain activity. The three measures were designed to capture associations at different levels of mental processing, from very automatic (electrical brain activity) to conscious and reasoned (questionnaire). At more conscious levels of cognitive processing, Facebook was seen as interesting, addictive, and highly personal. Results for the electrical brain activity measure show that Facebook tells less of a story and, surprisingly, is less personal than other forms of media. We discuss differences in results across the three measures and how our findings can inform the design of future social media systems.
The Phagocytosis-Associated Respiratory Burst in Human Monocytes Is Associated with Increased Uptake of Glutathione

During the phagocytic respiratory burst, oxygen is converted to potent cytotoxic oxidants. Monocytes and macrophages are potentially long-lived, and we have hypothesized that protective mechanisms against oxidant stress are varied and fully expressed in these cells. We report here that the respiratory burst in monocytes is accompanied by an increase in the uptake of [ 35 S]glutathione ([ 35 S]GSH) after 20–30 min to levels up to 10-fold greater than those at baseline. By 30 min, 49% of the cell-associated radioactivity was in the cytosol, 41% was in membrane, and 10% was associated with the nuclear fraction. GSH uptake was inhibited by catalase, which removes hydrogen peroxide (H 2 O 2 ), and micromolar H 2 O 2 stimulated GSH uptake effectively in monocytes and also lymphocytes. Oxidation of GSH to glutathione disulfide with H 2 O 2 and glutathione peroxidase prevented uptake. Acivicin, which inhibits GSH breakdown by γ-glutamyl transpeptidase (GGT), had no effect on the enhanced uptake seen during the respiratory burst. Uptake of cysteine or cystine, possible products of GGT activity, stayed the same or decreased during the respiratory burst. These results suggest that a GGT-independent mechanism is responsible for the enhanced GSH uptake seen during the respiratory burst. We describe here a sodium-independent, methionine-inhibitable transport system with a K m (8.5 μM) for GSH approximating the plasma GSH concentration. These results suggest that monocytes have a specific GSH transporter that is triggered by the release of H 2 O 2 during the respiratory burst and that induces the uptake of GSH into the cell. Such a mechanism has the potential to protect the phagocyte against oxidant damage.
Cytokine-mediated regulation of ovarian function. Tumor necrosis factor alpha inhibits gonadotropin-supported ovarian androgen biosynthesis.

Resident ovarian macrophages have been implicated in the regulation of ovarian function, presumably through local paracrine secretion of regulatory molecules (i.e. cytokines). One such macrophage product, tumor necrosis factor (TNF) alpha, has been shown to attenuate the gonadotropin-dependent differentiation of the somatic ovarian (estrogen-producing) granulosa cell. This study examines the possibility that TNF alpha may also regulate the adjacent androgen-producing theca interstitial cell. The basal accumulation of androsterone (the major androgenic steroid), synthesized by whole ovarian dispersates from immature rats, remained unchanged following treatment with TNF alpha (30 ng/ml) alone. In contrast, concurrent treatment with increasing concentrations of TNF alpha (0.03-30 ng/ml), yielded dose-dependent inhibition of the human chorionic gonadotropin (1 ng/ml)-stimulated accumulation of androsterone. This reversible and immunoneutralizable effect of TNF alpha was characterized by a minimal effective dose of 0.1 ng/ml, a median inhibitory dose of 0.9 ng/ml, a maximal inhibitory effect of 90%, and a minimal time requirement of less than or equal to 48 h. Comparable results were obtained when using highly purified theca interstitial cells, thereby indicating that TNF alpha is capable of exerting a direct inhibitory effect at the level of the ovarian androgen-producing cell. TNF alpha action was not accounted for by alterations in the plated viable cell mass. Instead, treatment with TNF alpha resulted in significant inhibition of the human chorionic gonadotropin-supported accumulation of cAMP, the putative second messenger of gonadotropin hormonal action. TNF alpha action at sites distal to cAMP generation was associated with profound inhibition of the conversion of the [3H]pregnanolone (3 alpha-hydroxy,5 alpha-pregnane-20-one) and [3H]17 alpha-hydroxypregnanolone (3 alpha, 17 alpha-dihydroxy,5 alpha-pregnane-20-one) substrates to androsterone, suggesting stimulation of 20 alpha-hydroxysteroid dehydrogenase activity, inhibition of 17 alpha-hydroxylase/17:20 lyase activity, or both. Taken together, these findings indicate that TNF alpha, acting at relatively low concentrations, is capable of inhibiting gonadotropin-supported ovarian androgen biosynthesis by selectively modulating the activity of relevant key steroidogenic enzymes. As such, these observations suggest that the theca interstitial cell is a site of TNF alpha reception and action and that TNF alpha, possibly of resident ovarian macrophage origin, may partake in the regulation of ovarian androgen production, an effect due in part to inhibition of the activity of the key steroidogenic enzymes 17 alpha-hydroxylase/17:20 lyase.
Hemodynamic observations in evacuation of molar pregnancy

Abstract The high incidence of pulmonary complications following evacuation of molar gestation at 16 weeks' size or greater (27%) prompted us to institute hemodynamic monitoring in seven of these patients in an effort to determine etiologies and possible modes of therapy for this potentially life-threatening complication. Our data indicate that following suction curettage with general anesthesia there appears to be impairment of ventricular performance of a transient nature as manifested by increases in central venous pressure, mean pulmonary artery pressure, and pulmonary capillary wedge pressure, despite a slight elevation in cardiac index and a decrease in systemic vascular resistance. The possible role of general anesthesia in the development of these changes, as well as the role of the colloid osmotic pressure to wedge gradient in the development of pulmonary complications, is discussed.
Does Light Direct Life Toward Cosmic Awareness

The evolution of life on our planet is briefly reviewed emphasizing the roles played by light and language. Life and language are regarded as a single interlocking system which light has stimulated to serve as an organ of cosmic awareness. Light first rewarded life with energy. Light then stimulated life to grow upward from the surface of our planet. Life is now integrating into itself detailed knowledge of the cosmos by decoding the vast store of information contained in celestial light.
Uptake of the carborane derivative of cholesteryl ester by glioma cancer cells is mediated through LDL receptors.

Purpose. This study was to elucidate the mechanism of cellular uptake of cholesteryl 1,12-dicarba-closo-dodecaboranel-carboxylate (BCH), a new anti-cancer carborane derivative of cholesteryl ester, by glioma cancer cells. Methods. BCH (solubilized with liposomal formulation) was incubated with SF-763 and SF-767 glioma cell lines in the presence of different amounts of monoclonal anti-LDL receptor antibody for cellular uptake studies. Various amounts of lipoprotein deficient serum (LPDS) were also used during the uptake. The effect of calcium ion and low temperature on BCH uptake were investigated. In addition, the transfer of BCH from liposomes to low-density lipoprotein (LDL) particles was determined through gradient ultracentrifugation. Results. BCH uptake by these glioma cells was significantly inhibited by the monoclonal antibody. The uptake by both cell lines was reversely correlated with the amount of LPDS. The presence of calcium ion promoted the BCH uptake, whereas the low temperature decreased the BCH uptake. After 16 h incubation, about 46% of BCH was transferred from liposomes to LDL particles. Conclusions. These results strongly suggested that the cellular uptake of BCH (in liposomal formulation) by SF-763 and SF-767 glioma cell lines is mediated through LDL receptors.
Quantitative analysis of gene expression in living adult neural stem cells by gene trapping

The potential of neural stem cells (NSCs) for the treatment of neurodegenerative diseases makes the identification and characterization of genes involved in neural stem cell responses therapeutically important. Although technologies exist for measuring gene expression in cells, they often provide only a representative expression profile specific to a stimulus and time. We developed a complementary technology based on a retroviral-vector gene-trap approach that uses beta-lactamase-induced disruption of fluorescence resonance energy transfer in the fluorophore CCF-2/AM. A library of 'tagged' adult rat NSCs was generated by transduction with gene-trap virus produced from a single-integrant packaging cell line that allowed us to quantitatively analyze dynamic gene expression changes in real time in living NSCs. Using this library we identified previously unknown genes regulated by oxidative stress, indomethacin and factors that induce differentiation, and show that one of the trapped genes, Sox6, is sufficient to induce astrocytic differentiation when overexpressed.
New insights into nNOS regulation of vascular homeostasis.

Every cell in the human body is dependent upon the delivery of adequate concentrations of O2 to maintain normal cellular functions, which are principally powered by ATP derived from mitochondrial oxidative phosphorylation. The anatomical matching of O2 delivery to demand is determined by the production of secreted factors that stimulate blood vessel growth, most notably VEGF (1). Every step of its biogenesis, from transcription of VEGF gene sequences in the nucleus and protection of the resulting mRNA against degradation to the ribosomal translation and folding of VEGF protein in the endoplasmic reticulum and transport via the Golgi system to the plasma membrane for secretion, is O2 regulated, as is the expression of its cognate receptor on vascular endothelial cells (1–3). Anatomical responses to changes in O2 demand occur on a scale of days, whereas other physiological responses resulting in alterations in O2 delivery occur on a scale of seconds. Systemic responses are mediated by chemoreceptor cells in the carotid body that depolarize in response to reduced arterial O2 tension, leading to reflex changes in ventilation, heart rate, and vascular tone (4). The vasculature within tissues also responds to acute regional hypoxia by dilation of arterioles that control the flow of blood into each capillary bed, as in the case of increased O2 consumption in skeletal muscle during exercise (5). In contrast, when systemic hypoxia occurs as a result of vascular hypotension (shock), the adrenergic nervous system directs redistribution of blood flow to maintain the perfusion of the heart and brain at the expense of other organs such as the gastrointestinal tract. However, under conditions of chronic hypoxia, the contractile response of arteries to hypoxia is blunted in an attempt to maintain tissue viability.
The meal pattern of genetically obese (ob/ob) mice *

The purpose of this investigation was to determine the meal pattern that characterizes the increased food intake of the ob/ob mouse. The major result was that obese mice ate larger and less frequent meals than lean mice during the dark phase of the light-dark cycle. There was a sex difference in that obese females ate the largest meals. To investigate the possibility that the different meal patterns observed in obese and lean mice was an artifact of the temporal criterion used to define a minimal intermeal interval, the meal patterns of obese and lean male mice were analyzed using two temporal criteria, 1 min and 5 min, and a behavioral criterion, the behavioral sequence of satiety. This analysis demonstrated that obese mice ate larger meals than lean mice whenever the criterion for an intermeal interval included the behavioral sequence of satiety. The mechanisms responsible for the increased meal size in obese mice are not known, but we suggest that preabsorptive satiety mechanisms may be less potent in obese mice.
Phytochrome Photoconversion in Vivo Comparison between Measured and Predicted Rates

The measured rates of phytochrome photoconversion in vivo, in etiolated cabbage (Brassica oleracea L.) seedlings and cucumber (Cucumis sativus L.) cotyledons, under blue, red, and far red irradiation, are significantly different from those predicted on the basis of the spectral photon flux distributions of the light sources and optical parameters of purified phytochrome. The geometrical relationships between the light source and the irradiated sample affect the rate of phytochrome photoconversion, which is significantly faster in cabbage seedling laying flat on white, wet filter paper than in seedlings in a vertical position. Light reflected from the white filter paper on the bottom of the dish contributes significantly to phytochrome photoconversion. Substituting the white filter paper with a less reflective black one results in a significant decrease of the rate of phytochrome photoconversion in cucumber cotyledons.
A further note on the Kirkwood equation in atomic diamagnetism

Abstract We point out that the Thomas-Fermi model of the atom and its generalizations exactly satisfy the Kirkwood relation between-the atomic polarizability and diamagnetic susceptibility.
Contribution of S4 Charges to Gating Mechanism in Hv Channels

Voltage-gated proton (HV) channels have been shown to play an essential role in immune system function. They are homologous to the voltage-sensing domain (VSD) of voltage-gated potassium (Kv) channels. In contrast to the tetramer structure of Kv channels, we found that Hv channels are dimers with just two S4 segments. Recently, we showed that the total effective gating charges are 5.9±0.4e0 in the dimer and 2.7±0.1e0 in the monomer and that S4 movement (containing 3 arginines) precedes channel opening. However, which specific arginine from S4 segment contributes to the effective gating charge is still unknown. To answer this question, we replaced each arginine residue with asparagines separately in Ciona intestinalis Hv channels. Patch-clamp recordings in Xenopus oocytes showed a dramatic decrease of total gating charges when measured by the limiting slope method: 1.9, 2.9 and 2.2 e0 for R255, R258 and R261, respectively. In addition, our cysteine accessibility measurements are consistent with an outward movement of these three S4 charges during channel opening. According to our findings, we conclude that the S4 segment moves and functions as the voltage sensor and all S4 charges contribute to voltage gating in Hv channels.
Nonpoint source nitrogen loads to delaware lakes and streams

Abstract Sixty-two watersheds and thirty lakes were sampled for one year. Nitrogen loads were estimated for each lake and watershed. The nitrogen loading rates varied from 8·0 to 38·5 kg/ha. A greater percentage of nitrogen was transported in baseflow than stormflow. Soil type and percentage of cropland had an influence on the nitrogen loading rate. Excessively well drained soils and higher nitrogen loading rates than poorly drained soils. Watersheds with a large percentage of the drainage area in cropland had the highest nitrogen loading rates. Broiler production did not have a large impact on the nitrogen loading rate.
Kainate elicits elevated nuclear calcium signals in retinal neurons via calcium-induced calcium release

Intracellular Ca2+ was imaged in cultured neonatal rat retinal neurons using the Ca(2+)-sensitive dye fluo-3 and confocal scanning laser microscopy. Depolarization via elevation of bath K+ concentration resulted in large cytoplasmic and nuclear Ca2+ signals; responses in the nucleus exceeded those of the cytoplasm. Glutamate or kainate application elicited the same intracellular pattern of elevated Ca2+ signals. Kainate stimulation was blocked by the non-NMDA receptor antagonist, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), and greatly reduced by removing Ca2+ from the bath and adding ethylene glycol-bis (beta-amino-ethyl ether) N,N,N',N'-tetraacetic acid (EGTA). Kainate was equally effective in eliciting Ca2+ signals when bath Na+ was replaced with equimolar concentrations of choline, or in the presence of the NMDA receptor antagonist, 2-amino-5-phosphonovaleric acid (APV). Caffeine treatment significantly reduced the kainate-induced intracellular Ca2+ response. These results suggest that Ca2+ can enter through the kainate receptor of retinal neurons and amplify the Ca2+ signals in the cytoplasm and nucleus by releasing Ca2+ from intracellular stores.
Deoxygenated phosphorothioate inositol phosphate analogs: Synthesis, phosphatase stability, and binding affinity

Abstract Inositol phosphates, such as 1 d -myo-Inositol 1,4,5-trisphosphate [Ins(1,4,5)P3], are cellular second messengers with potential roles in cancer prevention and therapy. It typically is difficult to attribute specific pharmacological activity to a single inositol phosphate because they are rapidly metabolized by phosphatases and kinases. In this study, we have designed stable analogs of myo-inositol 4,5-bisphosphate [Ins(4,5)P2] and Ins(1,4,5)P3 that retain the cyclohexane scaffold, but lack hydroxyl groups that might be phosphorylated and have phosphate groups replaced with phosphatase-resistant phosphorothioates. An Ins(1,4,5)P3 analog, 1 d -2,3-dideoxy-myo-inositol 1,4,5-trisphosphorothioate, was synthesized from (-)-quebrachitol, and an Ins(4,5)P2 analog, 1 d -1,2,3-trideoxy-myo-inositol 4,5-bisphosphorothioate, was prepared from cyclohexenol. The Ins(1,4,5)P3 analog was recognized by Ins(1,4,5)P3 receptor with a binding constant (Kd) of 810 nM, compared with 54 nM for the native ligand Ins(1,4,5)P3, and was resistant to dephosphorylation by alkaline phosphatase under conditions in which Ins(1,4,5)P3 is extensively hydrolyzed. Analogs developed in this study are potential chemical probes for understanding mechanisms of inositol phosphate actions that may be elucidated by eliciting specific and prolonged activation of the Ins(1,4,5)P3 receptor.
Disruption of the proto-oncogene int-2 in mouse embryo-derived stem cells: a general strategy for targeting mutations to non-selectable genes

Gene targeting—homologous recombination of DNA sequences residing in the chromosome with newly introduced DNA sequences—in mouse embryo-derived stem cells promises to provide a means to generate mice of any desired genotype. We describe a positive and negative selection procedure that enriches 2,000-fold for those cells that contain a targeted mutation. The procedure was applied to the isolation of hprt− and int-2− mutants, but it should be applicable to any gene
Multicultural Education in a Post-Race Political Age: Our Movement at Risk?

The 2008 elections ushered in a new era in U.S. politics with implications for race relations and social justice activity. Drawing parallels between the contemporary African American community and splintering undercurrents in the National Association for Multicultural Education (NAME), the author urges cross-generational coalescence around an organizational agenda accentuating critical multicultural education for this new era.
A retrospective review of the primus first MTP joint double-stemmed silicone implant.

Implant arthroplasty has been a surgical alternative for correction of hallux rigidus for many decades. A study is presented reviewing the authors’ experience using the (Tornier/Futura) Primus double-stemmed silicone implant. A total of 144 patients representing 201 implants were identified and invited to participate in the study. The postoperative period ranged from 32 to 108 months, with an average of 66.4 months. Chart review was performed on all cases. This review revealed that there were 2 implants that had been removed, each for reasons other than implant breakdown. Several indications in addition to hallux rigidus were found, including hallux valgus with arthritis, geriatric bunion, rheumatoid arthritis, and iatrogenic and traumatic arthritis. The outcomes are presented for all patients, with additional breakdown by their indication for surgery. In all, 54 patients involving 70 implants responded and were clinically evaluated. This study included a Visual Analogue Scale, Foot and Ankle (VAS FA) pat...