cssi/SciSciGPT-SciSciNet huggingface dataset:
Multicompartment Tubular Micromotors Toward Enhanced Localized Active Delivery

A tubular micromotor with spatially resolved compartments is presented toward efficient site-specific cargo delivery, with a back-end zinc (Zn) propellant engine segment and an upfront cargo-loaded gelatin segment further protected by a pH-responsive cap. The multicompartment micromotors display strong gastric-powered propulsion with tunable lifetime depending on the Zn segment length. Such propulsion significantly enhances the motor distribution and retention in the gastric tissues, by pushing and impinging the front-end cargo segment onto the stomach wall. Once the micromotor penetrates the gastric mucosa (pH ≥ 6.0), its pH-responsive cap dissolves, promoting the autonomous localized cargo release. The fabrication process, physicochemical properties, and propulsion behavior are systematically tested and discussed. Using a mouse model, the multicompartment motors, loaded with a model cargo, demonstrate a homogeneous cargo distribution along with approximately four-fold enhanced retention in the gastric lining compared to monocompartment motors, while showing no apparent toxicity. Therapeutic payloads can also be loaded into the pH-responsive cap, in addition to the gelatin-based compartment, leading to concurrent delivery and sequential release of dual cargos toward combinatorial therapy. Overall, this multicompartment micromotor system provides unique features and advantages that will further advance the development of synthetic micromotors for active transport and localized delivery of biomedical cargos.
Anti-inflammatory drugs

In the ideal sequence of events in developing a drug, one would first select a particular disease and then proceed to learn sufficient relevant facts about it (the first difficulty); then, one would know how to predict which particular chemical structure would have the required therapeutic effects without toxicity (the second difficulty); one would then synthesize the drug (perhaps difficult but probably possible); then, one would have valid and reliable testing models of the disease in animals (not presently known for any skin disease); after proof of efficacy and safety, finally the drug would be tested in the clinic (possible). Such a sequence has never been accomplished. The etiology of inflammatory diseases, particularly, is known to a limited extent only, and the dermal manifestations of them are understood still less. The pharmacologist therefore has many good opportunities here for rewarding work.
Reserving coronavirus disease 2019 vaccines for global access: cross sectional analysis.

Abstract Objective To analyze the premarket purchase commitments for coronavirus disease 2019 (covid-19) vaccines from leading manufacturers to recipient countries. Design Cross sectional analysis. Data sources World Health Organization’s draft landscape of covid-19 candidate vaccines, along with company disclosures to the US Securities and Exchange Commission, company and foundation press releases, government press releases, and media reports. Eligibility criteria and data analysis Premarket purchase commitments for covid-19 vaccines, publicly announced by 15 November 2020. Main outcome measures Premarket purchase commitments for covid-19 vaccine candidates and price per course, vaccine platform, and stage of research and development, as well as procurement agent and recipient country. Results As of 15 November 2020, several countries have made premarket purchase commitments totaling 7.48 billion doses, or 3.76 billion courses, of covid-19 vaccines from 13 vaccine manufacturers. Just over half (51%) of these doses will go to high income countries, which represent 14% of the world’s population. The US has reserved 800 million doses but accounts for a fifth of all covid-19 cases globally (11.02 million cases), whereas Japan, Australia, and Canada have collectively reserved more than one billion doses but do not account for even 1% of current global covid-19 cases globally (0.45 million cases). If these vaccine candidates were all successfully scaled, the total projected manufacturing capacity would be 5.96 billion courses by the end of 2021. Up to 40% (or 2.34 billion) of vaccine courses from these manufacturers might potentially remain for low and middle income countries–less if high income countries exercise scale-up options and more if high income countries share what they have procured. Prices for these vaccines vary by more than 10-fold, from $6.00 (£4.50; €4.90) per course to as high as $74 per course. With broad country participation apart from the US and Russia, the COVAX Facility—the vaccines pillar of the World Health Organization’s Access to COVID-19 Tools (ACT) Accelerator—has secured at least 500 million doses, or 250 million courses, and financing for half of the targeted two billion doses by the end of 2021 in efforts to support globally coordinated access to covid-19 vaccines. Conclusions This study provides an overview of how high income countries have secured future supplies of covid-19 vaccines but that access for the rest of the world is uncertain. Governments and manufacturers might provide much needed assurances for equitable allocation of covid-19 vaccines through greater transparency and accountability over these arrangements.
Use of Antiretroviral Therapy for a US Medicaid Enrolled Pediatric Cohort with HIV.

Appropriate antiretroviral therapy use in children with Human Immunodeficiency Virus (HIV) is essential for optimizing clinical outcomes and preventing HIV transmission. To describe and determine correlates of HIV antiretroviral therapy (ART) persistence and implementation for children and adolescents in the United States. We studied Medicaid enrollees (ages 2–19 years) with HIV in 14 states in 2011 and 2012. We defined non-persistence as a discontinuation of an ART regimen for at least 90 days, and calculated implementation as the proportion of days on ART while persistent. We used Cox proportional regression and logistic regression to determine characteristics associated with ART non-persistence and poor (< 90%) implementation, respectively. Among those with ≥ 1 year of observation (n = 8679), 55.7% never received ART. For ART recipients (n = 3849), 34.9% discontinued ART. Correlates of ART non-persistence included older age (e.g., 15–19 vs. 2–5 years [adjusted hazard ratio (aHR) 2.9, 95% CI 2.1–4.0]; females vs. males (aHR 1.2; 1.1–1.3); mental health conditions (aHR 1.3; 1.1–1.5), drug/alcohol abuse (aHR 1.2; 1.0–1.5) and HIV-related conditions (aHR 1.2; 1.0–1.4). Those with an outpatient visit were less likely to discontinue an ART (aHR 0.32; 0.28–0.36). During persistent episodes, 42.3% had poor ART implementation. Correlates of poor implementation included females vs. males (aOR 1.2; 95% CI 1.0–1.3), Black vs. White race (aOR 1.3; 95% CI 1.1–1.7) and Hispanic/Latino vs. White (aOR 1.3; 1.0–1.8). Among Medicaid youth with HIV, there were low rates of ART exposure, and ART discontinuation was common. Correlates of persistence and implementation differed, suggesting a need for varying clinical interventions to improve connection to care and ensuring ongoing engagement with ART use.
Population Pharmacokinetic Analysis of Dexmedetomidine in Children using Real-World-Data Obtained from Electronic Health Records and Remnant Clinic Samples

Dexmedetomidine is commonly used as part of intraoperative anesthetic management and for sedation and pain control after surgery in children. Dexmedetomidine infusion dose is typically given on a fixed weight basis with titration to achieve sedation goals while avoiding potential toxicities. Pharmacokinetic (PK) studies are useful for accurate prediction of the individual dose required to achieve sedation and analgesia goals without toxicity, but lack of PK data is a challenge in precision dosing for pediatric populations. In this study, population PK models were developed using a nonlinear mixed-effects modeling approach and used to explore the relationship between PK profile and clinical, demographic, and genotype covariates. A simulation study was used to demonstrate the impact of important covariates on concentration using a fixed weight dosing scheme. Our final study population included data from 354 patients age 0 to 22 years (median age 16 months). In the final two-compartment model with fixed allometric weight scaling we found significant effects of both age and UGT2B10 genotype. The population PK parameter estimates (95% confidence interval) for a standard 70 kg weight were clearance 22.3 (18.3 - 27.3) L/hr, central compartment volume of distribution 133 (112 - 157) L, intercompartmental clearance 24.1 (19.4 - 29.9) L/hr, peripheral compartment volume of distribution 5230 (3310 - 8260) L. Our study provides support for the feasibility of using real-world data obtained from EHRs and remnant samples to perform population PK analysis for groups of patients where traditional PK studies are challenging to perform. Inclusion of UGT2B10 genotype in the model significantly improved the model fit, but the effects were not large enough to impact clinical dosing.
The Language of the Xūz and the Fate of Elamite

This article discusses the language of the Xūz mentioned in Arabic sources, endorsing the view that it is the latest attestation of the Elamite language. Drawing on models from historical sociolinguistics, it also studies the problem of mutual acculturation between speakers of Elamite and Persian in antiquity.
Pondering the mechanism of receptor tyrosine kinase activation: The case for ligand-specific dimer microstate ensembles

Abstract Receptor tyrosine kinases (RTKs) are single-pass membrane proteins that regulate cell growth, differentiation, motility, and metabolism. Here, we review recent advancements in RTK structure determination and in the understanding of RTK activation. We argue that further progress in the field will necessitate new ways of thinking, and we introduce the concept that RTK dimers explore ensembles of microstates, each characterized by different kinase domain dimer conformations, but the same extracellular domain dimer structure. Many microstates are phosphorylation-competent and ensure the phosphorylation of one specific tyrosine. The prevalence of each microstate correlates with its stability. A switch in ligand will lead to a switch in the extracellular domain configuration and to a subsequent switch in the ensemble of microstates. This model can explain how different ligands produce specific phosphorylation patterns, how receptor overexpression leads to enhanced signaling even in the absence of activating ligands, and why RTK kinase domain structures have remained unresolved in cryogenic electron microscopy studies.
Moral injury in civilians: associations with trauma exposure, PTSD, and suicide behavior.

Background Moral injury (MI) describes emotional, spiritual, and social suffering that can arise following psychological trauma. Prior research in military pop ulations indicates the relevance of MI to adverse psychological outcomes, such as post-traumatic stress disorder (PTSD) and suicidal behaviours, and shows evidence for MI as a unique construct. Minimal studies of MI have been implemented in civilians, usually restricted to small samples with a specific set of traumatic experiences, despite the conceptual relevance of MI to non-military trauma reactions more broadly (e.g. feelings of betrayal towards a perpetrator of sexual abuse). Objective To address this problem, we assessed MI in trauma-exposed civilians to examine ways in which this construct was related to and distinct from trauma and traumatic stress-related problems, including PTSD and depression. Method We adapted an existing MI scale, Moral Injury Events Scale (MIES) and administered this measure to 81 men and women along with measures of trauma exposure, PTSD and depression, and also asked participants about past suicide attempts. Results We observed that both greater exposure and distress related to potentially morally injurious events were associated with higher trauma exposure, particularly childhood maltreatment, as well as post-traumatic and depressive psychopathology. However, even after accounting for current PTSD and depression symptoms, MI exposure (F = 6.05, p = .017) was significantly higher among participants who had previously attempted suicide. Conclusions These pilot data reveal the ways in which MI is associated with trauma exposure, PTSD and depression and highlight the salience of MI in civilians. Similarly, these data demonstrate the unique relevance of MI to suicide behaviours, independent of post-traumatic psychopathology, indicating that this construct may be an understudied contributor to suicide risk in civilians.
Ventricular-Arterial Interaction: Cardiac Effects of Mean versus Pulsatile Arterial Load

The influence of the two principal components of vascular loading, mean resistance and pulsatile load, on the contractile and energetic performance of the left ventricle are discussed. The data suggest that while large changes in mean resistance leading to varying ejection fraction can influence both cardiac systolic mechanics and energetic efficiency, substantial changes in pulsatile loading do not. They provide an explanation for why pulsatile loading does not necessarily result in a coronary supply/demand imbalance. By not significantly altering chamber systolic performance of elastance (i.e. stiffness), the pulsatile load results in parallel increases in coronary systolic pressure and flow, allowing adequate perfusion despite the reduced mean diastolic perfusion pressure. Future studies are required to better determine how cardiac disease alters the interplay between vascular load and cardiac performance.
A high performance low power implementation scheme for FSM

Finite state machine (FSM) takes an important part in digital logic system. FSMs partition is one of the effective methods in regards to low power technique. Most of time only one of sub-FSMs need to be clocked, consequently power is saved. In this paper, we propose a high performance algorithm based on state transitions probability and low complexity control logic to implement the partitioned FSMs. The cost from one sub-FSM to other sub-FSMs could be minimum, and the transitions probability in one sub-FSM should be maximum. Based on the low complexity of control logic, we further give an optimized hardware architecture for the partitioned FSM model. Our proposed scheme has been implemented by using tsmc 45 nm technology library. Experimental results show that an average power reduction of 59% has been obtained for a set of standard FSM benchmark circuits.
Psychological preparation for endoscopy: Physiological and behavioral changes in patients with differing coping styles for stress

Explicit repetitive, psychological preparation helps to lessen anxiety and discomfort for most patients undergoing their first endoscopic examination. This is particularly true for patients indentified as "sensitizers". For patients, identified as "repressors", limited explicit preparation was not helpful and, in terms of increased heart rates and required medication, may have had a deleterious effect.
Rewards for Rights Ratification? Testing for Tangible and Intangible Benefits of Human Rights Treaty Ratification

Among the explanations for state ratification of human rights treaties, few are more common and widely accepted than the conjecture that states are rewarded for ratification by other states. These rewards are expected to come in the form of tangible benefits - foreign aid, trade, and investment - and intangible benefits such as praise, acceptance, and legitimacy. Surprisingly, these explanations for ratification have never been tested empirically. We summarize and clarify the theoretical underpinnings of - reward-for-ratification‖ theories and test these propositions empirically by looking for increased international financial flows and public praise and recognition following ratification of four prominent human rights treaties. We find almost no evidence that states can expect increased tangible or intangible rewards after ratification. Given the lack of empirical support, explanations rooted in domestic politics seem a more appealing alternative for understanding human rights treaty ratification.
Effect of stigmatizing conditions on the use of personal space.

Two studies examine the use of personal space by persons in interactions involving stigmatized individuals. In the first, responses on a figure-placement task and on an attitude questionnaire are compared. In the second, interactions involving a person believed to have epilepsy are examined in regard to both initial interaction distance and eye contact. The expectation that the ascription of epilepsy to a stranger will result in less proximate interaction than in the case in which epilepsy is not ascribed to the stranger is supported. Degree of eye contact, however, was found not to differ for stigmatized and non-stigmatized interactions.
Spider diffraction: a comparison of curved and straight legs

It has been known for some time that, if curved legs rather than the usual straight ones are used in the spider that supports the secondary optics in certain telescopes, the visible diffraction effect is reduced. Fraunhofer theory is used to calculate the diffraction effects due to the curved leg spider. Calculated and photographic diffraction patterns are compared for straight and curved leg spiders.
Carbohydrate composition and electrophoretic properties of tomato polygalacturonase isoenzymes

Two polygalacturonase isoenzymes, PG I and PG II, were extracted from Murrieta tomato and purified by gel exclusion and ion-exchange chromatography. The kinetic constants and activation energies of the purified isoenzymes have been determined. Polygalacturonase I has two polypeptide chains (Mr = 47 500 and 41 400) whereas polygalacturonase II is a single polypeptide (Mr = 47 500) as shown by electrophoresis in polyacrylamide gels in the presence of sodium dodecyl sulphate. Both isoenzymes are glycoproteins. Through gas liquid chromatography, polygalacturonase II was shown to contain 4.6% neutral hexoses and 1.5% amino sugars. There are eight D-mannose, two L-fucose, two D-xylose and three N-acetylglucosamine residues per mole of PG II. The carbohydrate portion of PG II was shown to be attached to the protein part through an N-acetylglucosaminylasparaginyl bond.
Deviation of the Cosmic Background Radiation from a black‐body spectrum due to axion‐electromagnetic coupling

The low energy coupling of the electromagnetic field to the axion leads to two distinct dispersion relations for the electromagneticaxion oscillations. The one frequency being the normal electromagnetic (E. M.) oscillation while the other represents a coupled oscillation. When a non-zero chemical potential is associated with the axion-electromagnetic oscillation and the spectrum of the two oscillations are super-imposed, a formula emerges that suggests how the Cosmic Background Radiation (C.B.R.) might differ from that of a black body if axions do in fact couple to the background radiation.
QCD Phenomenology and Heavy Ion Physics

We describe application of saturation/Color Glass Condensate physics to heavy ion collisions, concentrating on several important observables. We show how simple saturationinspired assumptions about particle production in heavy ion collisions allow one to accurately describe total charged particle multiplicity as a function of the collision's centrality, of the center of mass energy, and of the particle rapidity. We will then describe how predictions of saturation physics can be tested by studying energy/rapidity dependence of particle spectra in p(d)A collisions. We concentrate on the nuclear modification factor RpA for gluon production. We show that at moderately high energy/rapidity the nuclear modification factor RpA exhibits Cronin enhancement. As the energy/rapidity increases, RpA decreases. At sufficiently high energy/rapidity RpA becomes less than 1 for all values of pTindicating the onset of suppression of gluon production due to quantum evolution effects. These predictions were confirmed by RHIC data.
PcG and trxG in plants – friends or foes

The highly-conserved Polycomb group (PcG) and trithorax group (trxG) proteins play major roles in regulating gene expression and maintaining developmental states in many organisms. However, neither the recruitment of Polycomb repressive complexes (PRC) nor the mechanisms of PcG and trxG-mediated gene silencing and activation are well understood. Recent progress in Arabidopsis research challenges the dominant model of PRC2-dependent recruitment of PRC1 to target genes. Moreover, evidence indicates that diverse forms of PRC1, with shared components, are a common theme in plants and mammals. Although trxG is known to antagonize PcG, emerging data reveal that trxG can also repress gene expression, acting cooperatively with PcG. We discuss these recent findings and highlight the employment of diverse epigenetic mechanisms during development in plants and animals.
Effects of Collision and Vibrational Energy on the Reaction of CH3CHO+(ν) with C2D4†

The reaction of acetaldehyde cations with ethene has been studied as a function of collision energy and acetaldehyde vibrational state. REMPI through different vibrational levels of the B electronic state is used to produce CH3CHO+ with controlled excitation in different vibrational modes. Reactions are studied in a guided ion beam instrument, including measurements of product ion recoil velocity distributions. In addition, we calculated the structures and energetics of 13 different complexes that potentially could serve as intermediates to reaction. Three reactions are observed. Hydrogen atom transfer (HT) dominates at low collision energies and is suppressed by collision energy and, to a lesser extent, vibration. The HT reaction is clearly direct at high collision energies but appears to be mediated by a reactant-like precursor complex at low energies. The most energetically favorable product channel corresponds to elimination of CH3 from an intermediate complex. Nonetheless, this channel accounts for ...
Transposable elements and fitness in Drosophila melanogaster.

Transposable elements constitute a significant fraction of the Drosophila melanogaster genome. The five families of moderately repeated transposable elements identified to date occupy dispersed and variable genomic locations, but have relatively constant copy numbers per individual. What effect to these elements have on the fitness of the individuals harboring them? Experimental evidence relating to this question is reviewed. The relevant data fall into two broad categories. The first involves the determination of the distribution of transposable elements in natural populations, by restriction mapping or in situ hybridization, and the comparison of the observed distribution with different theoretical expectations. The second approach is to study directly the effects of new transposable element-induced mutations on fitness. The P family of transposable elements is a particularly efficient mutagen, and the results of experiments in which initially P-free chromosomes are contaminated with P elements are disc...
The determination of concentration of bile acid in peripheral, portal and hepatic blood of cebus monkeys

Abstract A procedure for the determination of concentrations of bile salts in the peripheral, portal, and hepatic blood of Cebus monkeys is described. The methods were based on dilution calculations derived from the specific activities of labeled compounds in bile after the administration of C 14 -carboxyl-labeled bile salts. The Cebus monkeys appeared to have largely taurocholic and taurochenodeoxycholic acids in bile and in blood. Deoxycholic acid, which was formed in significant quantities in the intestine from cholic acid, was apparently reabsorbed to a minimum extent, since labeled taurodeoxycholate was not found in the bile after cholate administration and the monkey liver does not alter administered deoxycholate.
The effect of some sympathicomimetic amines and enzyme blocking agents on asthma in the guinea pig induced by antigen or histamine aerosols

Abstract 1.1. The inhibition of the epinephrine-destroying enzyme, monoamine oxidase, by iproniazid, thus making more exogenous or endogenous epinephrine available, does not influence the asthma in the guinea pig produced by a histamine aerosol. This confirms our previously reported findings. 2.2. The inhibition of a histamine-destroying enzyme, diamine oxidase (histaminase), by isoniazid, thus making more exogenous or endogenous histamine available, does not increase the asthma produced in guinea pigs by a histamine aerosol. 3.3. The antituberculous drug pyruvic acid isonicotinoyl hydrazone, which has little inhibiting action on either monoamine oxidase or diamine oxidase, increased the tolerance of the animals to the histamine aerosol. The mechanism is unexplained. 4.4. Amines related to epinephrine (phenylethylamine, amylamine, and Tyramine) had no influence on asthma produced by aerosols of histamine or antigen. 5.5. The pretreatment of the animals with iproniazid, which inhibits the action of monamine oxidase, destroying these amines more completely than it does epinephrine, failed to affect the influence of the asthma-inducing aerosols. 6.6. The protection against asthma produced by intraperitoneal injection of ephedrine was not enhanced by pretreatment with iproniazid. 7.7. Since Benadryl is also a moderate inhibitor of monoamine oxidase, its action in preventing histamine-induced asthma might be explained on that basis. The addition, however, of iproniazid in Benadryl-treated animals failed to potentiate the action of the latter. This supports the belief that the antiallergic action of Benadryl does not depend on monoamine oxidase. 8.8. The experiments herein described together with those previously reported by us lead to the conclusion that the action of monoamine oxidase cannot be the only mechanism in the prevention of anaphylaxis in the guinea pig. 9.9. Evidence is presented which indicates that the role of endogenous diamine oxidase (histaminase) in the regulation of histamine shock in the guinea pig is negligible.
Morphologic findings in explanted mitroflow pericardial bioprosthetic valves

Abstract Intrinsic structural deterioration (primary tissue degeneration) is the leading cause of failure of both Ionescu-Shiley and Hancock pericardial heart valves, as well as porcine aortic valve bioprostheses. 1–4 Although cuspal calcification is clearly the principal contributory pathologic process to failure of porcine valves, the relative roles of calcium, noncalcific tearing and other degenerative processes in pericardial valve failure are less well-established. 4 Early to intermediate clinical results with the Mitroflow ® (Mitroflow International, Inc., Richmond, British Columbia, Canada) pericardial heart valve have been favorable. 5,6 The present study sought to identify the morphologic changes and mechanisms of failure after long-term clinical function of this prosthesis.
Serial determination of plasma ethanol concentrations in mice

Abstract A technique permitting the serial determination of plasma ethonol concentration (PEC) in mice is described. Samples of blood, 5 μl in volume, are drawn from the infraorbital plexus. It was demonstrated that this source reflects the rapid dynamics of absorption and clearance after an intraperitoneal injection of ethanol. Samples taken from the tail showed a greatly delayed response and required 30 min to equilibrate with samples taken from the infraorbital plexus. The concentrations of ethanol were determined by gas chromatography. A precolumn removed the nonvolatile constituents thus permitting the injection of plasma directly into the instrument. The ratio of ethanol concentrations in red blood cells to plasma was found to be 0.62. This permitted the estimation of concentration of ethanol in whole blood: (1−0.38 H) × PEC; where H=the hematocrit.
Monogamy and high relatedness do not preferentially favor the evolution of cooperation

Phylogenetic analyses strongly associate nonsocial ancestors of cooperatively-breeding or eusocial species with monogamy. Because monogamy creates high-relatedness family groups, kin selection has been concluded to drive the evolution of cooperative breeding (i.e., the monogamy hypothesis). Although kin selection is criticized as inappropriate for modeling and predicting the evolution of cooperation, there are no examples where specific inclusive fitness-based predictions are intrinsically wrong. The monogamy hypothesis may be the first case of such a flawed calculation. A simulation model mutated helping alleles into non-cooperative populations where females mated either once or multiply. Although multiple mating produces sibling broods of lower relatedness, it also increases the likelihood that one offspring will adopt a helper role. Examining this tradeoff showed that under a wide range of conditions polygamy, rather than monogamy, allowed helping to spread more rapidly through populations. Further simulations with mating strategies as heritable traits confirmed that multiple-mating is selectively advantageous. Although cooperation evolves similarly regardless of whether dependent young are close or more distant kin, it does not evolve if they are unrelated. The solitary ancestral species to cooperative breeders may have been predominantly monogamous, but it cannot be concluded that monogamy is a predisposing state for the evolution of helping behavior. Monogamy may simply be coincidental to other more important life history characteristics such as nest defense or sequential provisioning of offspring. The differing predictive outcome from a gene-based model also supports arguments that inclusive fitness formulations poorly model some evolutionary questions. Nevertheless, cooperation only evolves when benefits are provided for kin: helping alleles did not increase in frequency in the absence of potential gains in indirect fitness. The key question, therefore, is not whether kin selection occurs, but how best to elucidate the differing evolutionary advantages of genetic relatedness versus genetic diversity.
Enhanced T cell responses due to diacylglycerol kinase ζ deficiency

Much is known about how T cell receptor (TCR) engagement leads to T cell activation; however, the mechanisms terminating TCR signaling remain less clear. Diacylglycerol, generated after TCR ligation, is essential in T cells. Its function must be controlled tightly to maintain normal T cell homeostasis. Previous studies have shown that diacylglycerol kinase ζ (DGKζ), which converts diacylglycerol to phosphatidic acid, can inhibit TCR signaling. Here we show that DGKζ-deficient T cells are hyperresponsive to TCR stimulation both ex vivo and in vivo. Furthermore, DGKζ-deficient mice mounted a more robust immune response to lymphocytic choriomeningitis virus infection than did wild-type mice. These results demonstrate the importance of DGKζ as a physiological negative regulator of TCR signaling and T cell activation.
Seasonal differences of vertical-transport efficiency in the tropical tropopause layer: On the interplay between tropical deep convection, large-scale vertical ascent, and horizontal circulations

[1] Winter-summer differences in the transport of air from the boundary layer to the lower stratosphere at low latitudes are investigated with ensembles of back trajectory calculations that track parcels from the 380 K isentropic surface to their convective detrainment in the tropical tropopause layer (TTL) during the winter of 2006–2007 and summer of 2007. Horizontal displacements for the trajectories are calculated from reanalysis data; potential temperature displacements are calculated from radiative heating rates derived from observed cloud, water vapor, ozone, and temperature variations; and the locations' convective detrainments are determined by satellite observations of convective clouds. Weaker upwelling in the TTL during boreal summer compared with that of winter both slows the ascent through the TTL and raises the height threshold that convective detrainment must surpass in order for ascent to occur, restricting the injection of new air into the stratosphere during summer. In addition, anticyclonic circulations associated with convective activity contribute to vertical transport in the TTL by guiding detrained air parcels through regions with the strongest upwelling. These features combine to make monsoon-related convection over the Indian subcontinent the dominant source of new air during summer. In contrast, winter sources are spread over the southern continents and the western Pacific Ocean. These seasonal differences imply that air entering the tropical stratosphere during summer is older but might nevertheless be more polluted than air entering during winter. While poor data sampling in the TTL makes it difficult to validate our results, they are bolstered by favorable comparisons with previous studies of the TTL, by sensitivity tests that reveal important dynamical influences on surface-to-stratospheric transport, and by the robustness of dynamical interactions that systematically associate deep convection with anticyclonic circulations and strong radiative heating in the TTL. Sensitivity experiments suggest that the aforementioned seasonal differences are sensitive to strong “large-scale” (on global space scales and seasonal time scales) perturbations. In particular, uncertainties in the vertical motion fields constrain our ability to draw definitive conclusions. However, trajectory statistics are not sensitive to small-scale perturbations, with the encouraging implication that our results are primarily associated with those features of the circulation that are the most likely to be robust.
Transformations in Density Estimation

Abstract For the density estimation problem the global window width kernel density estimator does not perform well when the underlying density has features that require different amounts of smoothing at different locations. In this article we propose to transform the data with the intention that a global window width is more appropriate for the density of the transformed data. The density estimate of the original data is the “back-transform” by change of variables of the global window width estimate of the transformed data's density. We explore choosing the transformation from suitable parametric families. Data-based selection rules for the choice of transformations and the window width are discussed. Application to real and simulated data demonstrates the usefulness of our proposals.
Stressed vegetation identification by SAR time series as an indicator of slope instability in Mississippi River levee segments

Surface vegetation reflects various characteristics of the soil on which it grows. Vegetation type and growth rate differences were observed between recently cracked surfaces and stable soil on earthen levees along the lower Mississippi River. We attempted to directly characterize the levee surface beneath the vegetation cover using X-band synthetic aperture radar from TerraSAR-X. Due to its short wavelength, however, most of the backscatter is from the vegetation rather than the soil. Hence a time-series of the SAR imagery was made over the time when vegetation growth and biomass were at their lowest and the multi-temporal radar backscatter pattern was used to identify healthy and stressed vegetation growing over stable and unstable (subject to slump slides) levee segments. Field data showed that vegetation was most vigorous over healthy or repaired levee surfaces and poorest over areas with surface cracks. Three time series of the HH and VV and HH-VV images were made for 6 dates over a 7 month period. Correlation with field data and analysis revealed that imagery from October through February was most effective in identifying the target vegetation differences. In this time span the differences in vigor of the vegetation were greatest between healthy levee surfaces and those with cracks on them (which could lead to potential levee failures). The 3 time series were classified independently using field derived training polygons and the stressed vegetation class was extracted from it. More than 90% of the known slump slides were identified by the classification but a significant number of `false positives' resulted.
Factors controlling decarburization in HVOF sprayed nano-WC/Co hardcoatings

Abstract The mechanism of decarburization in HVOF sprayed nano-WC/Co coatings has been investigated. The controlling factor is heterogeneous melting and localized superheating of the high surface area feed powder during spraying. This has the effect of causing extensive dissolution of the WC nanoparticles in the liquid Co, accompanied by rapid reaction of the dissolved C with oxygen in the flame environment. Upon cooling down from the peak temperature in the flame, the Co-rich liquid, now deficient in C, forms W 2 C and/or W phases, depending on the loss of carbon by gasification. Thus, it is concluded that HVOF sprayed high surface area nano-WC/Co powder is more susceptible to decarburization than conventional WC/Co powder, which is in agreement with observation.
Class Attendance in Undergraduate Courses

ABSTRACT Many college instructors complain about class attendance, but few data have been gathered on when and why students miss class. In this study, I examined class attendance in 17 sections of undergraduate psychology classes and found that class attendance decreased from the beginning to the end of the semester and that attendance displayed moderate correlations with course grades. I also found that students missed classes most frequently because of the time needed to complete other course work, because the classes were boring, because of illness, and because classes interfered with their social life. Finally, I have attempted to explain attendance behavior in terms of self-regulatory theory.
The ‘natural’ vegetation of the Mexican Bajío: Archival documentation of a 16th-century Savanna environment

Neo-ecologists make assumptions about a ‘natural’ or potential vegetation when they argue whether a particular landscape is in secondary and degraded condition. Similarly, paleoecologists attempt to infer a three-dimensional biotic mosaic from a core taken in a low-lying wetland. Yet with millennia of human disturbance, climatic fluctuation, biotic response to long-term climatic trends or catastrophic ‘events’, and co-evolution between Holocene vegetation and human land-use, ‘natural ecosystems’ have not been in equilibrium. While past vegetation changes can be traced, efforts to reconstruct potential vegetation are probably unrealistic. This paper assembles 16th century landscape descriptions of the Bajio of Central Mexico from archival repositories, to characterise the landscape at the time of Spanish intrusion. Attention is focused on five major landscape elements: (1) Riparian woodlands of mesquite, bald cypress and willow, with reed stands; (2) Level, vertisolic plains, with a low-tree savanna (mesquite-acacia-grass); (3) Steeper piedmont plains with stony substrates, probably favoring xeric, thorn-bush associations; (4) Rough uplands with a mix of mesquite-acacia woodland, scrub oak, and thorn bush; and (5) Mountains dominated by live and deciduous oak woodlands. The biotic mosaic of the 16th century appears similar to that of the modern spontaneous vegetation in physiognomic terms, despite changes in structure. Areas of older indigenous settlement were affected by local vegetation disturbance, with partial deforestation near lakes Cuitzeo and Yuriria. While Spanish-Criollo intrusion (1540–1640) brought new, potentially destructive landuse methods, there is no evidence of additional landscape degradation in the Bajio until well into the 18th century. Dramatic changes in hydrology and riparian vegetation are quite recent. Archival documentation provides a complementary methodology to re-examine the interplay of edaphic variation, climate and cumulative land-use in understanding contemporary vegetation, and it can assist in converting proxy data into a three-dimensional landscape.
Genome evolution and functional divergence in Yersinia.

The steadily increasing number of prokaryotic genomes has accelerated the study of genome evolution; in particular, the availability of sets of genomes from closely related bacteria has made exploration of questions surrounding the evolution of pathogenesis tractable. Here we present the results of a detailed comparison of the genomes of Yersinia pseudotuberculosis IP32593 and three strains of Yersinia pestis (CO92, KIM10, and 91001). There appear to be between 241 and 275 multigene families in these organisms. There are 2,568 genes that are identical in the three Y. pestis strains, but differ from the Y. pseudotuberculosis strain. The changes found in some of these families, such as the kinases, proteases, and transporters, are illustrative of how the evolutionary jump from the free-living enteropathogen Y. pseudotuberculosis to the obligate host-borne blood pathogen Y. pestis was achieved. We discuss the composition of some of the most important families and discuss the observed divergence between Y. pseudotuberculosis and Y. pestis homologs. J. Exp. Zool. (Mol. Dev. Evol.) 306B, 2006. © 2006 Wiley-Liss, Inc.
Adaptive Calibration Of Radio Interferometer Data

Radio interferometer observations are, essentially, samples of V, the Fourier transform of the radio brightness, I, on a patch of sky. The dominant errors usually are ascribable to individual elements of the array. Most damaging, often, are phase errors due to atmospheric refraction, but amplitude errors also may be serious. The sampling distribution improves as an observing run progresses since, as the earth rotates, any pair of elements samples V at different spatial frequencies lying along a curve. Adaptive calibration can be achieved as follows: Assumptions on the analytic properties of I lead to a measure of the consistency of the observations, from a given instant, with the total set of data; given an appropriate error model, an overdetermined system of equations in the unknown errors results; correcting the data accordingly, an improved estimate of I is derived; and the procedure may be repeated. This encompasses schemes proposed by Readhead and Wilkinson, and by Cotton, for compensation of phase errors in very-long-baseline interferometry (VLBI); similar methods are proposed by Muller and Buffington for optical telescopes. Results in analysis of Very Large Array (VLA) data are extremely encouraging. The computational expense is a few times that of standard methods.
Lhx2 links the intrinsic and extrinsic factors that control optic cup formation

A crucial step in eye organogenesis is the transition of the optic vesicle into the optic cup. Several transcription factors and extracellular signals mediate this transition, but whether a single factor links them into a common genetic network is unclear. Here, we provide evidence that the LIM homeobox gene Lhx2, which is expressed in the optic neuroepithelium, fulfils such a role. In Lhx2-/- mouse embryos, eye field specification and optic vesicle morphogenesis occur, but development arrests prior to optic cup formation in both the optic neuroepithelium and lens ectoderm. This is accompanied by failure to maintain or initiate the expression patterns of optic-vesicle-patterning and lens-inducing determinants. Of the signaling pathways examined, only BMP signaling is noticeably altered and Bmp4 and Bmp7 mRNAs are undetectable. Lhx2-/- optic vesicles and lens ectoderm upregulate Pax2, Fgf15 and Sox2 in response to BMP treatments, and Lhx2 genetic mosaics reveal that transcription factors, including Vsx2 and Mitf, require Lhx2 cell-autonomously for their expression. Our data indicate that Lhx2 is required for optic vesicle patterning and lens formation in part by regulating BMP signaling in an autocrine manner in the optic neuroepithelium and in a paracrine manner in the lens ectoderm. We propose a model in which Lhx2 is a central link in a genetic network that coordinates the multiple pathways leading to optic cup formation.
Magnetic chiral ionic liquids derived from amino acids

Novel room temperature magnetic chiral ionic liquids derived from amino acids were synthesized and their magnetic properties as well as chiral discrimination abilities were investigated.
The complex domestication history of the common bean

A new study reports the genome of common bean (Phaseolus vulgaris) and genome-wide resequencing data from both wild and domesticated accessions. These data confirm that common bean was domesticated at least twice, in Mesoamerica and South America, and also provide a framework to identify genes that contributed to the phenotypic changes associated with domestication.
Serum magnesium and type-2 diabetes in African Americans and Hispanics: a New York cohort.

Objectives: The aim of this study was to examine the relationship of serum Mg with stage of diabetes measured by fasting serum glucose in a cohort of 485 African American and Hispanic adults.Methods: The cross sectional Rosetta study was designed to assess body composition in a multi-racial cohort of healthy adults living in New York City. The data utilized for the current analyses were collected during the years 1990 to 2000. Serum Mg and glucose were measured after a 10–12 hour fast. Dual-energy x-ray absorptiometry was used to measure fat mass (FM) and fat free mass (FFM).Results: The mean age of the cohort was 53 ± 16 years. Hispanics had significantly lower (p < 0.05) mean serum Mg levels (0.82 ± 0.07 mmol/L vs. 0.85 ± 0.07 mmol/L) and FFM (48.8 ± 10.9 kg vs. 50.9 ± 10.3 kg) compared to African Americans. In both race/ethnic groups, individuals classified as having diabetes had significantly (p < 0.001) lower serum concentrations of Mg (0.80 ± 0.07 mmol/L) compared to the normal group (0.84 ± 0.07 mm...
On the second-order spin-orbit interaction for proton-nucleus scattering☆

Abstract An approximate evaluation of the KMT second-order multiple scattering terms which give rise to an additional spin-orbit interaction has been made. It is found that this contribution is sufficiently large to call into doubt the conclusion that the KMT theory is not able to explain the experimental polarization observed for protons in the 500 MeV range incident on nuclei.
Self-reported ethnicity, genetic structure and the impact of population stratification in a multiethnic study

It is well-known that population substructure may lead to confounding in case-control association studies. Here, we examined genetic structure in a large racially and ethnically diverse sample consisting of five ethnic groups of the Multiethnic Cohort study (African Americans, Japanese Americans, Latinos, European Americans and Native Hawaiians) using 2,509 SNPs distributed across the genome. Principal component analysis on 6,213 study participants, 18 Native Americans and 11 HapMap III populations revealed four important principal components (PCs): the first two separated Asians, Europeans and Africans, and the third and fourth corresponded to Native American and Native Hawaiian (Polynesian) ancestry, respectively. Individual ethnic composition derived from self-reported parental information matched well to genetic ancestry for Japanese and European Americans. STRUCTURE-estimated individual ancestral proportions for African Americans and Latinos are consistent with previous reports. We quantified the East Asian (mean 27%), European (mean 27%) and Polynesian (mean 46%) ancestral proportions for the first time, to our knowledge, for Native Hawaiians. Simulations based on realistic settings of case-control studies nested in the Multiethnic Cohort found that the effect of population stratification was modest and readily corrected by adjusting for race/ethnicity or by adjusting for top PCs derived from all SNPs or from ancestry informative markers; the power of these approaches was similar when averaged across causal variants simulated based on allele frequencies of the 2,509 genotyped markers. The bias may be large in case-only analysis of gene by gene interactions but it can be corrected by top PCs derived from all SNPs.