cssi/SciSciGPT-SciSciNet huggingface dataset:
Precision Medicine-Right Treatment, Right Patient, Right Time, Wrong Approach?

In his 2015 State of the Union address, American President Barack Obama announced the Precision Medicine Initiative as a “bold new research effort to revolutionize how we improve health and treat disease.” This was perhaps the first time the general population was exposed to the greater concept of precision medicine and capped years of escalating hype amongst the scientific community. Nearly 2 years later, as the luster of precision medicine has faded, the scientific research community has recoiled from overly optimistic expectations. Thus began the onerous introspective search for systematic flaws that have limited the realization of the full potential of all that precision medicine promises to offer. In a recent policy forum piece published in Science , Hey and Kesselheim argue that the current system is invalid and the process by which scientific discoveries are …
Angiographic management of the left hepatic artery disruption following motor vehicle accident.

Abstract Trauma is a leading cause of death in younger individuals. Blunt abdominal trauma has the potential to mask severe injuries—there can be serious organ or vascular injury underneath intact skin. Increasingly, there is a trend toward nonoperative management of blunt abdominal trauma. We report the case of a left hepatic artery transection managed in the interventional radiology suite.
Genome-Wide Sensitivity Analysis of the Microsymbiont Sinorhizobium meliloti to Symbiotically Important, Defensin-Like Host Peptides.

The model legume species Medicago truncatula expresses more than 700 nodule-specific cysteine-rich (NCR) signaling peptides that mediate the differentiation of Sinorhizobium meliloti bacteria into nitrogen-fixing bacteroids. NCR peptides are essential for a successful symbiosis in legume plants of the inverted-repeat-lacking clade (IRLC) and show similarity to mammalian defensins. In addition to signaling functions, many NCR peptides exhibit antimicrobial activity in vitro and in vivo Bacterial resistance to these antimicrobial activities is likely to be important for symbiosis. However, the mechanisms used by S. meliloti to resist antimicrobial activity of plant peptides are poorly understood. To address this, we applied a global genetic approach using transposon mutagenesis followed by high-throughput sequencing (Tn-seq) to identify S. meliloti genes and pathways that increase or decrease bacterial competitiveness during exposure to the well-studied cationic NCR247 peptide and also to the unrelated model antimicrobial peptide polymyxin B. We identified 78 genes and several diverse pathways whose interruption alters S. meliloti resistance to NCR247. These genes encode the following: (i) cell envelope polysaccharide biosynthesis and modification proteins, (ii) inner and outer membrane proteins, (iii) peptidoglycan (PG) effector proteins, and (iv) non-membrane-associated factors such as transcriptional regulators and ribosome-associated factors. We describe a previously uncharacterized yet highly conserved peptidase, which protects S. meliloti from NCR247 and increases competitiveness during symbiosis. Additionally, we highlight a considerable number of uncharacterized genes that provide the basis for future studies to investigate the molecular basis of symbiotic development as well as chronic pathogenic interactions.IMPORTANCE Soil rhizobial bacteria enter into an ecologically and economically important symbiotic interaction with legumes, in which they differentiate into physiologically distinct bacteroids that provide essential ammonia to the plant in return for carbon sources. Plant signal peptides are essential and specific to achieve these physiological changes. These peptides show similarity to mammalian defensin peptides which are part of the first line of defense to control invading bacterial populations. A number of these legume peptides are indeed known to possess antimicrobial activity, and so far, only the bacterial BacA protein is known to protect rhizobial bacteria against their antimicrobial action. This study identified numerous additional bacterial factors that mediate protection and belong to diverse biological pathways. Our results significantly contribute to our understanding of the molecular roles of bacterial factors during legume symbioses and, second, provide insights into the mechanisms that pathogenic bacteria may use to resist the antimicrobial effects of defensins during infections.
Copper-Catalyzed Alkene Aminoazidation as a Rapid Entry to 1,2-Diamines and Installation of an Azide Reporter onto Azahetereocycles

A copper-catalyzed aminoazidation of unactivated alkenes is achieved for the synthesis of versatile unsymmetrical 1,2-diamine derivatives. This transformation offers an effective approach to installing an amide and an azide from two diffenent amino precursors onto both terminal and internal alkenes, with remarkable regio- and stereoselectivity. Mechanistic studies show that this diamination reaction proceeds via a nucleophilic amino cyclization followed by an intermolecular C–N bond formation using electrophilic azidoiodinane. This pathway differs from previous azidoiodinane-initiated alkene functionalization, suggesting new reactivity of azidoiodinane. Furthermore, this aminoazidation reaction provides an efficient strategy to introduce azide, one of the most useful chemical reporters, onto a broad range of bioactive azaheterocycles, offering new opportunities in bioorthogonal chemistry and biological studies. Rapid syntheses of 5-HT2C agonist, (−)-enduracididine and azido-cholesterol derivatives demonst...
Time‐Dependent Cryospheric Longwave Surface Emissivity Feedback in the Community Earth System Model

Author(s): Kuo, C; Feldman, DR; Huang, X; Flanner, M; Yang, P; Chen, X | Abstract: Frozen and unfrozen surfaces exhibit different longwave surface emissivities with different spectral characteristics, and outgoing longwave radiation and cooling rates are reduced for unfrozen scenes relative to frozen ones. Here physically realistic modeling of spectrally resolved surface emissivity throughout the coupled model components of the Community Earth System Model (CESM) is advanced, and implications for model high-latitude biases and feedbacks are evaluated. It is shown that despite a surface emissivity feedback amplitude that is, at most, a few percent of the surface albedo feedback amplitude, the inclusion of realistic, harmonized longwave, spectrally resolved emissivity information in CESM1.2.2 reduces wintertime Arctic surface temperature biases from −7.2 ± 0.9 K to −1.1 ± 1.2 K, relative to observations. The bias reduction is most pronounced in the Arctic Ocean, a region for which Coupled Model Intercomparison Project version 5 (CMIP5) models exhibit the largest mean wintertime cold bias, suggesting that persistent polar temperature biases can be lessened by including this physically based process across model components. The ice emissivity feedback of CESM1.2.2 is evaluated under a warming scenario with a kernel-based approach, and it is found that emissivity radiative kernels exhibit water vapor and cloud cover dependence, thereby varying spatially and decreasing in magnitude over the course of the scenario from secular changes in atmospheric thermodynamics and cloud patterns. Accounting for the temporally varying radiative responses can yield diagnosed feedbacks that differ in sign from those obtained from conventional climatological feedback analysis methods.
Comparison between Two Radiological Methods for Assessment of Tooth Root Resorption: An In Vitro Study.

Purpose. This study aims to verify the validity of the radiographic image and the most effective radiological techniques for the diagnosis of root resorption to prevent, cure, and reduce it and to verify if radiological images can be helpful in medical and legal situations. Methods. 19 dental elements without root resorption extracted from several patients were examined: endooral and panoramic radiographs were performed, with traditional and digital methods. Then the root of each tooth was dipped into 3-4 mm of 10% nitric acid for 24 hours to simulate the resorption of the root and later submitted again to radiological examinations and measurements using the same criteria and methods. Results. For teeth with root resorption the real measurements and the values obtained with endooral techniques and digital sensors are almost the same, while image values obtained by panoramic radiographs are more distorted than the real ones. Conclusions. Panoramic radiographs are not useful for the diagnosis of root resorption. The endooral examination is, in medical and legal fields, the most valid and objective instrument to detect root resorption. Although the literature suggests that CBCT is a reliable tool in detecting root resorption defects, the increased radiation dosage and expense and the limited availability of CBCT in most clinical settings accentuate the outcome of this study.
The Nature and Origin of Tribochemistry

Tribochemistry can be defined as the chemical reactions that occur between the lubricant/environment and the surfaces under boundary lubrication conditions. The precise nature of the chemical reactions is not well understood. What causes the reactions to take place is also a subject of speculation. Surface analysis of the surface and the reaction products yields insufficient information for a full understanding of the nature and origin of the chemical reactions. The reaction mixture is complex and the quantity is very small. Classical analytical techniques provide elemental concentration but the organic portion of the reaction products eludes definition. Recent observation of surface emissions of electrons, charged particles, from rubbing surfaces invites speculation that this emission provides the source of energy causing tribochemical reactions to take place. This study reviews our current knowledge of tribochemistry and examines the issue of the source of tribochemistry in boundary lubrication. Experiments were designed to examine the issue of whether mechanical disruption of surface bonds can lead to the formation of reaction products. The second issue is whether these reaction products correspond to those observed under normal rubbing conditions. Thermally induced reaction products were also examined for comparison. Surfaces covered with a monolayer of stearic acid molecules were scratched by a glass lens covered with a layer of diamond particles. Unidirectional scratches were made at 20-30 nm depth. The reaction products were monitored by a grazing angle FTIR capable of detecting the spectrum of a monolayer. The spectrum was then compared with the spectrum from a thermally heated case and a rubbed case. Results suggest that such scratching indeed produces similar reaction products.
Future Orientations: Intergenerational Politics and Democratic Freedom

This paper examines the place of intergenerational politics in modern and contemporary political thought. I argue that even as more and more attention has been given to intergenerational dynamics of late, both theory and practice have been unable to deal with the fact that future generations have no clear way of participating in the democratic use of power. This paper begins with a review of the place of intergenerational concerns in the modern and contemporary political theory, focusing on three general approaches to the topic: generational sovereignty, generational representation, and generational distribution. Although the generational sovereignty approach taps into a powerful impulse, our aspiration to democratic freedom cannot override the fact that we live in a temporal continuum, inheriting and bequeathing particular historical contexts that demand attention. However, the impossibility of knowing future individuals also creates specific problems for any attempt to represent future concerns. At the same time, this does not remove the obligation on democrats to attend to future generations in some way. Meanwhile, philosophers tell us we should care about intergenerational justice and have attempted to work out the precise fair distribution of resources across time. But then why haven’t we done more to protect future generations? Working with Patchen Markell’s critique of the politics of recognition, I argue that we should instead focus on a set of self-directed practices that better acknowledge temporal intersubjective vulnerability and cultivate a particular orientation toward ourselves and the future.
Characteristics of clinical laboratory technician students and effects on program outcome.

Objective To characterize student attrition in CLT education programs and relate program outcome (graduate, voluntary withdrawal, or academic dismissal) to student characteristics in three clusters of variables: academic, background and demographic characteristics, and environmental factors. Design Longitudinal, prospective study using a written survey and follow-up data collection. Setting Not applicable. Participants 1527 students from 61 CLT academic-based educational programs located across the U.S. Interventions Not applicable. Main outcome measures Participants completed a forced-choice written survey eliciting demographic and background information and measuring variables related to their involvement with the academic program and environmental factors external to the college. Program outcome groups: graduates, voluntary withdrawals, and academic dismissals were compared on each variable. Results Graduates of CLT programs differ significantly from both academic dismissals and voluntary withdrawals on variables from all three variable clusters. Conclusion Student characteristics exhibited early in CLT programs may help identify those students who are at risk of academic failure or voluntary withdrawal. Knowledge of factors associated with lack of CLT program persistence may help educators design successful intervention programs to enhance retention.
Policy Analysis Applications of Forecasting and Simulation Models

Regional forecasting and policy analysis models are used to forecast the economic effects of a wide range of policy initiatives. The usefulness and accuracy of the predictions by these models depends as much on the inputs to the models and the interpretation of the results as it does on the models themselves. In this chapter, we present a sample of studies that have been done with models that use the structure set forth in chapter 7, as implemented by REMI.
PREOPERATIVE RISK FACTOR-BASED CARDIAC CATHETERIZATION IS ASSOCIATED WITH LOW CARDIAC MORBIDITY AND MORTALITY IN LIVER TRANSPLANT PATIENTS

Mortality post-transplantation historically was largely attributed to coronary artery disease (CAD). Current guidelines recommend screening with non-invasive modalities in patients with risk factors. An analysis of 1221 patients at Indiana University (IU) found a reduction in the incidence of
Effect of contact surface, plasticized and crosslinked zein films are cast on, on the distribution of dispersive and polar surface energy using the Van Oss method of deconvolution

Abstract This study characterized, the surface properties of plasticized and crosslinked zein films. We showed that the distribution of the surface energy into dispersive and polar components of the amphiphilic zein protein was strongly affected by the surface zein is cast on when zein was cast on polystyrene, polydimethylsiloxane (PDMS) and polytetrafluoroethylene (PTFE, Teflon™). Plasticized zein films had higher fractions of dispersive Lifshitz-Van der Waals (γ LW ) components than the Lewis acid base (γ AB ) polar components overall when the surface energy was analyzed and deconvoluted using the Van Oss method. When cast on PDMS the polar component increased, water contact angles were the lowest and the total surface free energy increased as a result. Oleic acid and glutaraldehyde concentration, were also varied during fabrication of the films in addition to contact surfaces. Film composition did not have an equally significant effect on the surface energy of films but as expected affected mechanical properties.
The role of nanoparticle size and ligand coverage in size focusing of colloidal metal nanoparticles

Controlling the size distribution of nanoparticles is important for many applications and typically involves the use of ligands during synthesis. In this study, we show that the mechanism of size focusing involves a dependence of the growth rate on the size of the nanoparticles and the ligand coverage on the surface of the nanoparticles. To demonstrate these effects, we used in situ small angle X-ray scattering (SAXS) and population balance kinetic modeling (PBM) to investigate the evolution of size distribution during the synthesis of colloidal Pd metal nanoparticles. Despite temporal overlap of nucleation and growth, our in situ SAXS show size focusing of the distribution under different synthetic conditions (different concentrations of metal and ligand as well as solvent type). To understand the mechanism of size focusing using PBM, we systematically studied how the evolution of the nanoparticle size distribution is affected by nucleation rate, and dependence of the growth rate constant on ligand surface coverage, and size of the nanoparticles. We show that continuous nucleation contributes to size defocusing. However, continuous nucleation results in different reaction times for the nanoparticle population leading to time and size-dependent ligand surface coverage. Using density functional theory (DFT) calculations and Bronsted–Evans–Polanyi relations, we show that as the population grows, larger nanoparticles grow more slowly than smaller ones due to lower intrinsic activity and higher ligand coverage on the surface. Therefore, despite continuous nucleation, the faster growth of smaller nanoparticles in the population leads to size focusing. The size focusing behaviour (due to faster growth of smaller nanoparticles) was found to be model independent and similar results were demonstrated under different nucleation and growth pathways (e.g. growth via ion reduction on the surface and/or monomer addition). Our results provide a microscopic connection between kinetics and thermodynamics of nanoparticle growth and metal–ligand binding, and their effect on the size distribution of colloidal nanoparticles.
H3.3 Nucleosome Assembly Mutants Display a Late-Onset Maternal Effect.

Maternally inherited RNA and proteins control much of embryonic development. The effect of such maternal information beyond embryonic development is largely unclear. Here, we report that maternal contribution of histone H3.3 assembly complexes can prevent the expression of late-onset anatomical, physiologic, and behavioral abnormalities of C. elegans. We show that mutants lacking hira-1, an evolutionarily conserved H3.3-deposition factor, have severe pleiotropic defects that manifest predominantly at adulthood. These late-onset defects can be maternally rescued, and maternally derived HIRA-1 protein can be detected in hira-1(−/−) progeny. Mitochondrial stress likely contributes to the late-onset defects, given that hira-1 mutants display mitochondrial stress, and the induction of mitochondrial stress results in at least some of the hira-1 late-onset abnormalities. A screen for mutants that mimic the hira-1 mutant phenotype identified PQN-80—a HIRA complex component, known as UBN1 in humans—and XNP-1—a second H3.3 chaperone, known as ATRX in humans. pqn-80 and xnp-1 abnormalities are also maternally rescued. Furthermore, mutants lacking histone H3.3 have a late-onset defect similar to a defect of hira-1, pqn-80, and xnp-1 mutants. These data demonstrate that H3.3 assembly complexes provide non-DNA-based heritable information that can markedly influence adult phenotype. We speculate that similar maternal effects might explain the missing heritability of late-onset human diseases, such as Alzheimer’s disease, Parkinson’s disease, and type 2 diabetes.
A Control Method for Smooth Transition from Motoring to Generating Modes in Switched Reluctance Machines

This study presents a smooth transition algorithm to prevent the over currents in the phase windings of a switched reluctance machine (SRM) during transitions between motoring and generating modes. The proposed algorithm modifies the excitation angles of the SRM control during transitions by predicting the peak current of the phases for any operating conditions. Being applicable for a wide range of speed, the algorithm is discussed more for high speed operations due to the electromagnetic and mechanical dynamics of the SRMs. A Finite Element Analysis (FEA) of an 18/12 type SRM is utilized to develop its electromagnetic, circuit and mechanical models for the dynamic simulations. The performance of the proposed control algorithm is verified for various scenarios through the dynamic simulations.
Nueva edición crítica de El lugar sin límites de José Donoso en Colección Biblioteca Chilena: notas en torno a un proyecto de edición

He tenido el honor y el placer de editar, para Coleccion Biblioteca Chilena de Ediciones Universidad Alberto Hurtado, esta novela de Jose Donoso (1924-1996) que, a mas de cincuenta anos de su primera edicion en Mexico (1966), constituye tanto una de las principales novelas del escritor chileno como un hito dentro la literatura latinoamericana. Agradezco al comite editorial de (an)ecdotica, especialmente a Ana Laura Zavala Diaz, que me invitara a participar del dialogo centrado en la labor ecdotica de textos con el que la revista contribuye, llenando desde su primer numero un vacio indiscutible en nuestro campo al proveer esta instancia de reflexion y colaboracion en torno al quehacer de rescate y fijacion de textos iberoamericanos. Inicio esta nota resaltando el nexo de la novela con Mexico, para luego comentar brevemente los contenidos y detenerme en algunos detalles surgidos a partir del trabajo ecdotico, asi como en el lugar que le dimos a los materiales de archivo del escritor en este volumen.
Psychosocial Determinants of Burn-Related Suicide: Evidence From the National Violent Death Reporting System.

Suicide is a unique phenomenon in humans. In 2017, over 47,000 Americans died by suicide, prompting a public health crisis. Suicide by burning, while one of the rarest forms of suicide, could be mitigated in part by early recognition and treatment of the underlying psycho social factors. To date, investigators have attempted to tease out the risk factors associated with this phenomenon through the examination of burn center chart reviews and repository data, but these studies were limited by small sample sizes. In order to fill this gap in the literature, the authors analyzed fourteen years of data (2003-2016) from the National Violent Death Reporting System. Suicides by burning (n =722) were compared to a reference group containing all other suicide types (n =166,949). Sociodemographic variables and psychosocial factors (e.g., mental health, substance use, and alcohol use) were included in the model. Due to the imbalance between the target and reference groups, rare event data analysis was utilized to reduce potential small sample estimation bias. Results indicated that females (OR=1.6, 95% CI: .50-2.83, p & .001), Caucasians (OR=1.7, 95% CI: 1.1-2.7, p & .001), victims with schizophrenia (OR = 5.4, 95% CI: 3.7-7.8, p & .001), and victims with eating disorders (OR= 5.6, 95% CI: 1.9-8.6, p & .001) are significantly more likely to commit suicide by burning. These results contribute new knowledge to what is currently known about suicidal burn-related behaviors and supports interventions that focus on mitigating this insidious public health problem.
Dynamic Consensus Networks: Dynamic Graph Definitions and Controllability Analysis Using the Behavioral Approach

The focus of this paper is to study a generalization of consensus problems whereby the weights of network edges are no longer modeled as static gains, but instead are represented as dynamic systems coupling the nodes, which might also be more general than an integrator, leading to the notion of dynamic consensus networks. We transform each concept of static graph theory into dynamic terms, out of which a generalized dynamic graph theory naturally emerges. We present a framework for dynamic graphs and dynamic consensus networks. This framework introduces the idea of dynamic degree, adjacency, incident, and Laplacian matrices in a way that naturally extends these concepts from the static case. We consider controllability for dynamic consensus networks. The ideas developed for dynamic graph theory, in conjunction with the behavioral approach, lead to the development of a controllability analysis methodology for dynamic consensus networks. The controllability conditions obtained using the behavioral approach cannot be applied for the general dynamic networks, such as identical LTI nodes with dynamic edges or even in the more general case with heterogeneous nodes. This is because of scalability in such dynamic networks. Thus, we develop controllability conditions based on node and interconnection (edge) parameters that guarantee controllability of the overall dynamic network.
Mass Spectrometry-Based Profiling of Plant Sphingolipids from Typical and Aberrant Metabolism

Mass spectrometry has increasingly been used as a tool to complement studies of sphingolipid metabolism and biological functions in plants and other eukaryotes. Mass spectrometry is now essential for comprehensive sphingolipid analytical profiling because of the huge diversity of sphingolipid classes and molecular species in eukaryotes, particularly in plants. This structural diversity arises from large differences in polar head group glycosylation as well as carbon-chain lengths of fatty acids and desaturation and hydroxylation patterns of fatty acids and long-chain bases that together comprise the ceramide hydrophobic backbone of glycosphingolipids. The standard methods for liquid chromatography-mass spectrometry (LC-MS)-based analyses of Arabidopsis thaliana leaf sphingolipids profile >200 molecular species of four sphingolipid classes and free long-chain bases and their phosphorylated forms. While these methods have proven valuable for A. thaliana based sphingolipid research, we have recently adapted them for use with ultraperformance liquid chromatography separations of molecular species and to profile aberrant sphingolipid forms in pollen, transgenic lines, and mutants. This chapter provides updates to standard methods for LC-MS profiling of A. thaliana sphingolipids to expand the utility of mass spectrometry for plant sphingolipid research.
Delays in presentation and mortality among Black patients with mechanical thrombectomy after large-vessel stroke at a US hospital.

OBJECTIVE The incidence and severity of stroke are disproportionately greater among Black patients. In this study, the authors sought to examine clinical outcomes among Black versus White patients after mechanical thrombectomy for stroke at a single US institution. METHODS All patients who underwent mechanical thrombectomy at a single center from January 1, 2014, through March 31, 2020, were retrospectively analyzed. Patients were grouped based on race, and demographic characteristics, preexisting conditions, clinical presentation, treatment, and stroke outcomes were compared. The association of race with mortality was analyzed in multivariable logistic regression analysis adjusted for potential confounders. RESULTS In total, 401 patients (233 males) with a reported race of Black (n = 28) or White (n = 373) underwent mechanical thrombectomy during the study period. Tobacco use was more prevalent among Black patients (43% vs 24%, p = 0.04), but there were no significant differences between the groups with respect to insurance, coronary artery disease, diabetes, illicit drug use, hypertension, or hyperlipidemia. The mean time from stroke onset to hospital presentation was significantly greater among Black patients (604.6 vs 333.4 minutes) (p = 0.007). There were no differences in fluoroscopy time, procedural success (Thrombolysis in Cerebral Infarction grade 2b or 3), hospital length of stay, or prevalence of hemicraniectomy. In multivariable analysis, Black race was strongly associated with higher mortality (32.1% vs 14.5%, p = 0.01). The disparity in mortality rates resolved after adjusting for the average time from stroke onset to presentation (p = 0.14). CONCLUSIONS Black race was associated with an increased risk of death after mechanical thrombectomy for stroke. The increased risk may be associated with access-related factors, including delayed presentation to stroke centers.
'Harvesting a participatory movement': Initial participatory action research with the Jewish Farmer Network

The Jewish Farmer Network (JFN) is a North American grassroots organization that mobilizes Jewish agricultural wisdom to build a more just and regenerative food system for all. This paper pre­sents methodological findings and reflections from the initial stages of a participatory action research (PAR) collaboration led by the authors and JFN organizers centered on Cultivating Culture, JFN’s inaugural conference in February 2020. For this early iterative phase, we used a PAR approach to guide event ethnography to both facilitate and understand collective movement building and action. This work included pre-conference collabo­rative research design, a participatory reflection and action workshop with roughly 90 participants, eval­uative surveys, short ethnographic interviews, and ongoing post-conference analysis with researchers and movement organizers. While this data was first analyzed and organized for JFN’s use, we present findings to demonstrate the effectiveness of fore­grounding event ethnography within a PAR re­search design at an early stage of movement for­mation, especially how elements of event ethnogra­phy can address some of the limitations of using PAR with a nascent network of farmers. Our work revealed themes in the movement of Jewish farm­ing: the politics of identity in movement building, the tensions around (de)politicization, and the production of Jewish agroecological knowledge. We reflect on the utility of using PAR to frame scholar-activism and propose future inquires for Jewish agrarianism.
Grounding Landscape Urbanism and New Urbanism

Landscape Urbanism developed in response to the dispersed, organic and edgeless nature of contemporary urbanism. Twenty-first century cities appeared to more closely resemble emergent ecological pr...
Role of CD4 and CD8 in T Cell Activation and Differentiation

Publisher Summary This chapter summarizes the role of CD4 and CD8 in both T cell activation and differentiation. CD4 and CD8 are cell surface glycoproteins expressed on T lymphocytes that have specificity for class II or class I major histocompatibility complex (MHC) proteins, respectively. These proteins play major roles in both the activation of mature peripheral T cells and the thymic differentiation process that leads to the mature T cell repertoire and the expression of CD4 and CD8 on mutually exclusive T cell subsets. The crystal structures of immunoglobulin-like domains of CD4 and CD8 are determined, binding sites for CD8 on class I MHC proteins and CD4 on class II MHC proteins are mapped, and both proteins are shown to be associated via their cytoplasmic tails with the relatively T cell specific, src -family tyrosine kinase p56 lck . The first indication that CD4 and CD8 may play a more active role in T cell receptor (TCR)-mediated cell signaling came from studies demonstrating that anti-CD4 and anti-CD8 monoclonal antibodies inhibited mitogen-induced activation in the absence of relevant MHC ligands.
Progression of alachlor-induced olfactory mucosal tumours.

Alachlor is an herbicide used primarily in the production of corn (maize), peanuts, and soybeans and is associated with cancer of the nasal cavity, thyroid, and stomach in rats. Previous work from our laboratory demonstrated that the nasal cavity tumours originate from the olfactory mucosa, and that neoplasms were present following 6 months of exposure (126 mg/kg/day in the diet). The studies presented herein were conducted to determine more precisely the earliest time point at which alachlor-induced tumours were present, and to describe the histological changes that occur en route to tumour formation. We determined that dramatic histological changes, including respiratory metaplasia of the olfactory mucosa, were present following 3 months of exposure, and the earliest alachlor-induced olfactory mucosal tumours were detected following 5 months of treatment. Because alachlor is positive in short-term mutagenicity assays with olfactory mucosal activation, and because of the relatively short time-to-tumour formation observed with alachlor, we also conducted a ‘stop’ study in which rats were treated with alachlor for 1 month and then held without further treatment for an additional 5 months. This study demonstrated that abbreviated alachlor exposure did not result in subsequent tumour formation within the 6-month observation period.
An introduction to Monte Carlo simulations in criminal psychology: applications in evaluating biased estimators for recidivism

Purpose – Studies in criminal psychology are inevitably undertaken in a context of uncertainty. One class of methods addressing such uncertainties is Monte Carlo (MC) simulation. The purpose of this paper is to provide an introduction to MC simulation for representing uncertainty and focusses on likely uses in studies of criminology and psychology. In addition to describing the method and providing a step-by-step guide to implementing a MC simulation, this paper provides examples using the Fragile Families and Child Wellbeing Survey data. Results show MC simulations can be a useful technique to test biased estimators and to evaluate the effect of bias on power for statistical tests. Design/methodology/approach – After describing MC simulation methods in detail, this paper provides a step-by-step guide to conducting a simulation. Then, a series of examples are provided. First, the authors present a brief example of how to generate data using MC simulation and the implications of alternative probability dis...
Regulators of Ca2+ Signaling in Mast Cells: Potential Targets for Treatment of Mast Cell-Related Diseases?

A calcium signal is essential for degranulation, generation of eicosanoids and optimal production of cytokines in mast cells in response to antigen and other stimulants. The signal is initiated by phospholipase C-mediated production of inositol1,4,5-trisphosphate resulting in release of stored Ca2+ from the endoplasmic reticulum (ER) and Golgi. Depletion of these stores activates influx of extracellular Ca2+, usually referred to as store-operated calcium entry (SOCE), through the interaction of the Ca2+-sensor, stromal interacting molecule-1 (STIM1 ), in ER with Orai1(CRACM1) and transient receptor potential canonical (TRPC) channel proteins in the plasma membrane (PM). This interaction is enabled by microtubular-directed reorganization of ER to form ER/PM contact points or “punctae” in which STIM1 and channel proteins colocalize. The ensuing influx of Ca2+ replenishes Ca2+ stores and sustains elevated levels of cytosolic Ca2+ ions-the obligatory signal for mast-cell activation. In addition, the signal can acquire spatial and dynamic characteristics (e.g., calcium puffs, waves, oscillations) that encode signals for specific functional outputs. This is achieved by coordinated regulation of Ca2+ fluxes through ATP-dependent Ca2+-pumps and ion exchangers in mitochondria, ER and PM. As discussed in this chapter, studies in mast cells revealed much about the mechanisms described above but little about allergic and autoimmune diseases although studies in other types of cells have exposed genetic defects that lead to aberrant calcium signaling in immune diseases. Pharmacologic agents that inhibit or activate the regulatory components of calcium signaling in mast cells are also discussed along with the prospects for development of novel SOCE inhibitors that may prove beneficial in the treatment inflammatory mast-cell related diseases.
Laser myoplasty for hypertrophic cardiomyopathy. In vitro experience in human postmortem hearts and in vivo experience in a canine model (transarterial) and human patient (intraoperative).

Abstract The feasibility of performing a myotomy/myectomy for hypertrophic cardiomyopathy (HC) by means of laser phototherapy was evaluated experimentally in vitro and in vivo, and the procedure then applied to a patient intraoperatively. In vitro experience revealed that the beam of an argon laser, delivered directly or via an optical fiber, could both cut and vaporize myocardium, producing a myotomy/ myectomy morphologically similar to that produced by the conventional blade technique. In vivo experiments, in which the beam of an argon laser was delivered via an optical fiber to the ventricular septum of a canine heart, confirmed that a laser myoplasty could be achieved in 4 of 5 dogs by a transarterial approach. Finally, laser myoplasty was performed intraoperatively in a patient with HC, using a 200-μ fiber interfaced with an argon laser. Measured laser power was 1.5 W; cumulative exposure was less than 4 minutes; the myoplasty was 4 × 1 × 0.5 cm. These investigations establish the feasibility of using laser therapy to create a myoplasty trough that is similar in appearance to that typically achieved by the conventional blade technique. Illumination of the intraventricular operative field and precise modeling of the myoplasty trough constitute the principal advantages of laser myoplasty for HC.
Teaching 7000 Students Per Year

The undergraduate program at the University of Texas has grown into the largest astronomy teaching program in the world, with some 7000 students per year (almost 20,000 credit hours). The department has 22.5 Ph.D.-level teaching faculty, about 45 graduate students, and about 40 pre-professional undergraduate majors. But most of the enrollment is in courses that satisfy the science requirements of students in liberal arts and non-technical majors. In 1985–86, 96.4 per cent of our undergraduate credit hours taught were in such classes. It is instructive to examine the historical reasons for our growth and its educational consequences, and to draw some conclusions from both for other programs.
Cellular signaling by peptides of the endothelin gene family.

Endothelins (ET) are a family of regulatory peptides synthesized by selected endothelial and epithelial cells that act in a paracrine fashion on nearby smooth muscle or connective tissue cells. We review the pathways of transmembrane signaling triggered by binding of endothelin peptides to receptors on the plasma membrane. Although our understanding of many components is unclear, endothelin peptides appear to evoke a phosphoinositide-linked signaling system that bears a striking resemblance to signaling pathways activated by other regulatory peptides. Expression of endothelin receptors and specific pathways stimulated by activated receptors are controlled in a cell- and tissue-specific manner, which perhaps explains the diverse biological actions of endothelin in different tissues. Complex negative feedback pathways regulate endothelin-induced signaling at the receptor and second messenger levels. Moreover, by regulating the activity of sequence-specific DNA binding proteins, short-term signals by ET can ...
Sequence constraints and concept identification.

Summary.-128 Ss performed on two concept learning problems within which the sequence of relevant cues was essentially random. For one problem a constant proportion (k) of irrelevant cues changed whenever the relevant cue remained the same on adjacent trials (S-transition) whereas the values of the irrelevant stimulus dimensions varied at random whenever different relevant cues appeared on adjacent trials (D-transition). Within the second problem, k irrelevant stimulus dimensions changed ac D-transitions, while the values of the irrelevant dimensions varied at random at S-transitions. For independent groups, k ranged from .00 to 1.00. Trial of last error proved ro be an increasing linear function of proportion of irrelevant dimensions changed at D-trsnsitions whereas the proportion changed at S-transitions made no d~fference. These results are difficult to ~nderstand in terms of an all-or-none model of concept identification in which it is assumed that cues are sampled at random. Detambel and Stolurow (1956, p. 40) have proposed that to maximize rate of concept identification: "(a) When the same relevant cue is presented on adjacent trials, as many as possible of the irrelevant stimulus components should have different values on the two trials, (b) When two different relevant cues are presented on adjacent trials, as many as possible of the irrelevant stimulus components should be kept constant.'' Detambel and Stolurow conducted a study in which a sequence composed according to the two rules was contrasted with a sequence ccmposed according to the inverse of these rules. The result was a striking superiority for the sequence constructed according to the rules on both the training series and a test series in which the training stimuli were presented randomly. The Detambel and Stolurow study showed only that a training series constructed according to two rules was better than a control series. There was no way of telling whether the superiority of the training series was due to changing the irrelevant stimulus components when the relevant cue remained the same, to holding constant the irrelevant components when the relevant cue changed, or to both of these conditions. Anderson and Guthrie (1966) found that both conditions have an effect. This experiment contrasted a short alternating series in which one relevant cue appeared on odd trials while another relevant cue appeared on even numbered trials, with a short constant training series in which the same relevant cue appeared in the stimulus configura
The changing etiology of chronic diarrhea in HIV-infected patients with CD4 cell counts less than 200 cells/mm3.

The changing etiology of chronic diarrhea in HIV-infected patients with CD4 cell counts less than 200 cells/mm 3
Form-birefringent slow light optical limiter

We discuss multilayer devices based on subwavelength form-birefringence to slow light, that enhance electric field strengths and induce index changes that modify the bandgap. Design considerations, fabrication processes and initial results are discussed.
Sexual Responsiveness in Women with Spinal Cord Injuries: Differential Effects of Anxiety-Eliciting Stimulation

Sexual dysfunction is a common problem in women after spinal cord injuries (SCIs). Recently, the use of anxiety-provoking stimulation has been explored as a means of improving sexual responses in able-bodied sexually functional and dysfunctional women. In this laboratory-based study, we assessed the sexual and autonomic responses of women with SCIs with varying degrees of preservation of sympathetic innervation to their genitals to respond to anxiety-provoking audiovisual (AV) stimulation. Subjects were 45 women with SCIs and 11 able-bodied women. For purposes of analysis, SCI subjects were grouped on the basis of the degree of preservation of sensation in the T11-L2 dermatomes. Results revealed that women with low sensory scores in these dermatomes achieved higher vaginal pulse amplitude (VPA) responses to audiovisual erotic stimulation after anxiety preexposure than after neutral preexposure; however, women with SCIs and the greatest degree of preservation of sensory function in the T11-L2 dermatomes, as well as able-bodied controls, did not. Moreover, these same 2 groups of subjects had a decrease in VPA responses during baseline periods in which an anxiety-provoking video sequence was shown, but not during the neutral sequence. It is concluded that these findings are due to the proximity of sensory and autonomic neurologic elements in the spinal cord. Moreover, they demonstrate the differential effects of sympathetic stimulation on genital sexual arousal.
Non-circular cross-section stellarators

The magnetic surfaces and rotational transform of a stellarator with low poloidal-field wave number and elliptical minor cross-section have been computed numerically by utilizing a predictor-corrector code. The surfaces exhibit stagnation points the positions of which are related to the aspect ratio of the ellipse and the l-number of the configuration. The rotational transform is less than in an equivalent stellarator with circular cross-section for the same toroidal and helical currents in the magnet coils.
Convergence and Performance Issues for Autocorrelation Based Adaptive Channel Shortening

We derive bounds on the signal to interference ratio performance of several blind channel shortening designs based on autocorrelation minimization. We focus in particular on the performance of these designs in oversampled communications systems with multiple receive antennas. The utility of the bounds is demonstrated by proving inherent performance problems with certain classes of designs that previous low dimensional plots of the cost functions were not able to predict. We conclude the paper by providing a convergence result for adaptive versions of these blind designs which can be coupled with the performance results to determine performance of the adaptive designs.
Modulation of dopamine uptake in rat nucleus accumbens: effect of specific dopamine receptor antagonists and sigma ligands

The ability of dopamine (DA) antagonists and sigma receptor ligands to alter [(3)H]-DA uptake was examined using synaptosomes prepared from the nucleus accumbens of female rats. Pre-incubation with compounds having a high affinity for sigma (rimcazole, haloperidol, and spiperone) receptors produced dose dependent inhibition of (3)H-DA uptake. Sulpiride, a pure DA D(2) antagonist had no effect. In contrast, DA uptake was potentiated in response to (+)-3-(3-hydroxyphenyl)-N-(1-propyl)piperidine, a mixed sigma receptor antagonist and DA D(2) receptor agonist. Similarly, SKF-10,047, a selective sigma receptor agonist, and progesterone, a putative endogenous ligand for the sigma receptor, produced significant increases in (3)[H]-DA uptake. These data suggest a potential role for sigma and DA ligands in the regulation of DA uptake in the nucleus accumbens.
Magneto-optical study of the I4 bound exciton in ZnTe☆

Abstract The I4 bound exciton at 2.315 eV in ZnTe is resolved into a quartet at fields from 40 – 148 kG. The field dependence of this quartet is qualitatively different from that of other exciton complexes in ZnTe. I4 is assigned as due to ionized, substitutional Li acceptors at Zn sites.
An exploratory stepwise discriminant function analysis of malingered and nondistorted responses to the Neuropsychological Symptom Inventory.

Clinicians are often asked to evaluate a patient's potential for malingering during a neuropsychological examination. This problem is particularly crucial when financial gain may hinge on the results of the assessment. Response distortion may occur even when a head injury has been verified by radiological means (e.g., MRI). Research in the identification of malingering has yet to produce results that are effective in the clinical setting. The present study addressed several shortcomings of past research with the use of a self-report symptom inventory. The responses of 242 subjects told to distort symptomology were compared to 128 nonmalingerers. A discriminant function analysis of these data produced a 90% hit rate overall with 2.3% false positives. The results were discussed in terms of clinical utility.
The effect of stimulus-response complexity on the reaction time of schizophrenics

To determine if the slower performance of schizophrenics is due to slower data processing, the reaction times (RT) of schizophrenic and non-schizophrenic psychiatric Ss (controls) were compared on a simple and two-choice jump RT task. Schizophrenics were slower than controls on both tasks; the slope of the schizophrenics was flatter than the controls. The latter finding indicated that the slower performance of the schizophrenics was not due to processing data more slowly than controls.