cssi/SciSciGPT-SciSciNet huggingface dataset:
Distinct Neural Properties in the Low-Frequency Region of the Chicken Cochlear Nucleus Magnocellularis

Topography in the avian cochlear nucleus magnocellularis (NM) is represented as gradually increasing characteristic frequency (CF) along the caudolateral-to-rostromedial axis. In this study, we characterized the organization and cell biophysics of the caudolateral NM (NMc) in chickens (Gallus gallus). Examination of cellular and dendritic architecture first revealed that NMc contains small neurons and extensive dendritic processes, in contrast to adendritic, large neurons located more rostromedially. Individual dye-filling study further demonstrated that NMc is divided into two subregions, with NMc2 neurons having larger and more complex dendritic fields than NMc1. Axonal tract tracing studies confirmed that NMc1 and NMc2 neurons receive afferent inputs from the auditory nerve and the superior olivary nucleus, similar to the adendritic NM. However, the auditory axons synapse with NMc neurons via small bouton-like terminals, unlike the large end bulb synapses on adendritic NM neurons. Immunocytochemistry demonstrated that most NMc2 neurons express cholecystokinin but not calretinin, distinct from NMc1 and adendritic NM neurons that are cholecystokinin negative and mostly calretinin positive. Finally, whole-cell current clamp recordings revealed that NMc neurons require significantly lower threshold current for action potential generation than adendritic NM neurons. Moreover, in contrast to adendritic NM neurons that generate a single-onset action potential, NMc neurons generate multiple action potentials to suprathreshold sustained depolarization. Taken together, our data indicate that NMc contains multiple neuron types that are structurally, connectively, molecularly, and physiologically different from traditionally defined NM neurons, emphasizing specialized neural properties for processing low-frequency sounds.
The Effects of Beetroot Juice on VO2max and Blood Pressure During Submaximal Exercise

Beetroot juice (BR) has been shown to reduce blood pressure (BP) at rest and improve several performance parameters during exercise. However, the effect of BR on BP during submaximal exercise has not been investigated and its effects on VO2max are inconclusive. The purpose of this study was to investigate the effects of BR on VO2max and BP during submaximal exercise. 20 healthy, recreationally trained volunteers (age 21.8±2.35 years, weight 75.10±10.62 kg, height 177.4±6.39 cm) participated in this study, which had a double-blind placebo controlled randomized crossover design. Participants supplemented with either 237 ml servings of placebo or 70 ml BR servings (nitrate concentration of 6.4 mmol/day) for 7 days. Participants completed a ramp treadmill protocol to determine VO2max. BP was taken at 70% max heart rate calculated using the Karvonen method. There was no significant change in VO2max after BR supplementation (51.07±6.12 ml/kg/min) versus placebo (50.46±6.06 ml/kg/min), t(19)=1.41, p=0.17. There was no significant change in either systolic BP after BR supplementation (180.65±23.37 mm Hg) versus placebo (177.65±22.07 mm Hg), t(19)=0.49, p=0.63, or in diastolic BP after BR (92.90±18.89 mm Hg) versus placebo (90.75±17.73 mm Hg), t(19)=0.51, p=0.62. BR did not affect VO2max, nor did it affect BP during submaximal exercise.
P133 Uncertainty is the new reality: The risk in using the virtual crossmatch as a gatekeeper to transplantation

Aim To evaluate fluctuations in HLA antibodies for kidney waitlist candidates to determine optimal screening frequency and reduce inaccuracies in virtual crossmatches assessments (VXM). Methods HLA antibodies were identified and assessed using phenotype panels (Lifecodes, Immucor) and single antigen panels (Labscreen, One Lambda). All sera were treated with hypotonic dialysis or Melon Column™ prior to testing to remove prozone interference. Results The new kidney allocation system has increased the use of VXMs to assess donor compatibility prior to acceptance of imported organs. During the month of November 2016, 111 VXMs were performed for kidney waitlist candidates; of those patients 28 (25%) had a change in their HLA antibody status over the course of their sample history. Six patients (5.4%) had an antibody increase that potentially impacted the VXM, i.e the change occurred within the three month window around the virtual assessment. Five patients had samples older than 30 days at time of VXM and upon receipt of a new sample a significant HLA antibody increase had occurred. For one patient, despite having a sample within 30 days of the VXM, there was an on going antibody increase and although the VXM was reported as flow cytometric crossmatch negative, the new reality was antibody at CDC crossmatch positive levels. Conclusions VXMs have increased most dramatically in our highly sensitized patients (>80% CPRA), accounting for 50% of the virtual crossmatches performed in our November cohort. This population was found to have a high incidence (25%) of HLA specific antibody fluctuations while on the waitlist. A 3 month screening interval was sufficient in producing accurate VXM assessments for nearly 95% of our cohort; however, accuracy was compromised for the remaining patients due to unanticipated changes between test samples. Better communication of inflammatory events that may trigger sensitization changes or preoperative testing is needed to ensure VXM accuracy, patient safety, and successful transplant outcomes. Download high-res image (208KB) Download full-size image
High-order discretization of a gyrokinetic Vlasov model in edge plasma geometry

Abstract We describe a new spatial discretization of a continuum gyrokinetic Vlasov model in axisymmetric tokamak edge plasma geometries. The geometries are represented using a multiblock decomposition in which logically distinct blocks are smoothly mapped from rectangular computational domains and are aligned with magnetic flux surfaces to accommodate strong anisotropy induced by the magnetic field. We employ a fourth-order, finite-volume discretization in mapped coordinates to mitigate the computational expense associated with discretization on 4D phase space grids. Applied to a conservative formulation of the gyrokinetic system, a finite-volume approach expresses local conservation discretely in a natural manner involving the calculation of normal fluxes at cell faces. In the approach presented here, the normal fluxes are computed in terms of face-averaged velocity normals in such a way that (i) the divergence-free property of the gyrokinetic velocity is preserved discretely to machine precision, (ii) the configuration space normal velocities are independent of mapping metrics, and (iii) the configuration space normal velocities are computed from exact pointwise evaluation of magnetic field data except for one term. The algorithms described in this paper form the foundation of a continuum gyrokinetic edge code named COGENT, which is used here to perform a convergence study verifying the accuracy of the spatial discretization.
Multivariate Calibration and Experimental Validation of a 3D Finite Element Thermal Model for Laser Powder Bed Fusion Metal Additive Manufacturing

Metal additive manufacturing (AM) typically suffers from high degrees of variability in the properties/performance of the fabricated parts, particularly due to the lack of understanding and control over the physical mechanisms that govern microstructure formation during fabrication. This paper directly addresses an important problem in metal AM: the determination of the thermal history of the deposited material. Any attempts to link process to microstructure in AM would need to consider the thermal history of the material. In situ monitoring only provides partial information and simulations may be necessary to have a comprehensive understanding of the thermo-physical conditions to which the deposited material is subjected. We address this in the present work through linking thermal models to experiments via a computationally efficient surrogate modeling approach based on multivariate Gaussian processes (MVGPs). The MVGPs are then used to calibrate the free parameters of the multi-physics models against experiments, sidestepping the use of prohibitively expensive Monte Carlo-based calibration. This framework thus makes it possible to efficiently evaluate the impact of varying process parameter inputs on the characteristics of the melt pool during AM. We demonstrate the framework on the calibration of a thermal model for laser powder bed fusion AM of Ti-6Al-4V against experiments carried out over a wide window in the process parameter space. While this work deals with problems related to AM, its applicability is wider as the proposed framework could potentially be used in many other ICME-based problems where it is essential to link expensive computational materials science models to available experimental data.
Postoptimal analysis of a linear program under simultaneous changes in matrix coefficients

This paper examines the sensitivity of a linear program to simultaneous changes in matrix coefficients. Consider a linear program whose coefficient matrix depends linearly on a scalar parameter θ. Previous research has attempted to express the optimal objective value z(θ) of the problem, as well as solutions to the primal and dual, as ratios of polynomial functions of θ over a range of θ. Herein, we study properties of z(θ) and the associated optimal basic feasible solution in a neighborhood about a fixed value \(\bar \theta\)of θ. We obtain readily computable formulas for the Taylor series’ (and hence all derivatives) of z(θ) and of the primal and dual optimal basic solutions about the point \(\bar \theta\). Furthermore, even under degeneracy, we show how to determine whether or not \(\bar \theta\)is one of finitely many possible values of θ for which derivatives of z(θ) may not exist, by examining the lexicographic order of a certain matrix. This test also reveals whether or not the formulas given represent left-sided and/or right-sided derivatives of z(θ) at \(\bar \theta\).
The Known and the Unknown in L2 Metalinguistic Performance

Lewis Thomas (1981, p. 49) has observed that “the greatest of all the accomplishments of twentieth-century science has been the discovery of human ignorance.” Thomas’s wisdom is not out of place in the final chapter of a book concerned with the contingencies, vagaries, individual differences, and uncertainties that characterize a diverse set of phenomena called metalinguistic performance, and that complicate the relationship of metalinguistic performance to theories of interlinguistic competence. It is important to understand that we do not have all the answers. Smugness is unwarranted.
Multi-level metacognition for adaptive behavior

Abstract Behavior adaptation is an integral aspect for autonomous agents to survive in a world where change is normal. Animals change their foraging routines and socializing habits based on predator risks in their environment. Humans adapt their behavior based on current interests, social norms, stress level, health conditions, upcoming deadlines and various other factors. Artificial agents need to effectively adapt to changes in their environment such that they can quickly adjust their behavior to maintain performance in the changed environment. In this paper, we present a multi-level metacognitive model that allows agents to adapt their behavior in various ways based on the resources available for metacognitive processing. As the agent operates at higher levels of this model, the agent is better equipped to adapt to a wider range of changes. The model has been tested on 2 different applications: (i) a reinforcement learner-based agent trying to navigate and collect rewards in a seasonal grid-world environment and (ii) a convolutional neural network-based agent trying to classify the signals in a radio frequency spectrum world and separate them into known modulations and unknown modulations.
The impact of music on vehicular performance: A meta-analysis

Abstract Various studies offer insightful perspectives on the potential impact of music-listening on driving performance. These studies, however, present conflicting views on the effect of music as either hindering or enhancing driving performance and advance inconclusive claims regarding how and to what extent specific music parameters affect vehicular performance. In this study, therefore, we conducted a systematic review and meta-analysis of relevant studies. First, we identified experimental studies that measured the effects of music-listening on driving performance through database searches using multiple variants including “car”, “driv*”, “perf*”, and “music*”; of the 118 publications reviewed, 12 met the inclusion criteria for the current meta-analysis. Second, we coded independent variables—i.e., tempo, volume, instrumentation, familiarity, musical style, the music’s source, and whether music was selected by the researchers or the drivers—and dependent variables—i.e., vehicular longitudinal and lateral control, driver reaction time, traffic signal violations, collisions, and driving scores. Third, we ran mixed-effects and random-effects models to identify both general tendencies and more particular trends related to the effect of music-listening on driving performance—driving performance is here understood as the combination of vehicle manipulation and road navigation. Consistent with anecdotal evidence, the results of this meta-analysis show that music-listening has a statistically significant detrimental effect on driving performance, specifically for collisions and longitudinal control. In contrast with anecdotal evidence, however, the results of this meta-analysis show a detrimental effect associated with music-listening at soft volumes and no significant difference in driving performance associated with tempo. The study’s findings contributed to the development of a process model, and the concluding discussion offers suggestions for future empirical investigations related to music and driving.
Focal liver lesions following Fontan palliation of single ventricle physiology: A radiology-pathology case series

Purpose Patients who have undergone Fontan palliation of single ventricle physiology congenital heart disease are prone to developing focal liver lesions. In our experience, the variety of lesions occurring in this population is greater than that described in the literature. The purpose of this study was to describe the breadth of biopsy-proven liver lesions in patients post-Fontan palliation of single ventricle physiology cared for at our institution. Methods We retrospectively identified patients who had previously undergone the Fontan operation and had a focal liver lesion biopsied between January 2000 and June 2018. Medical records were reviewed for lesion pathology, background liver findings, pertinent laboratory data, and demographic data. CT and MRI images were reviewed to describe imaging findings of the reported lesions. Results Twelve patients met inclusion criteria; 58% (7/12) of which were female. Fifteen lesions were biopsied including four macroregenerative/benign hepatocellular hyperplastic nodules, two hepatocellular adenomas, two hepatocellular carcinomas, two intrahepatic cholangiocarcinoma (in the same patient), one venous malformation, and one focus of vascularized scar tissue. Two additional lesions in patients postcardiac transplant were posttransplant lymphoproliferative disorder. Conclusion Patients who have undergone Fontan palliation of single ventricle physiology are prone to develop a variety of liver lesions, both benign and malignant.
We Are One After All

The sustainability necessary to make the world a better place rests on five Ps – People, Peace, Prosperity, Partnership and Planet. Sustainable community systems are organic spaces where there is peace born of justice. Sustainability as peace is seen as the result of partnership, a partnership that is for betterment – in other words, for prosperity. Without people, peace, partnership, prosperity, the planet will not be taken care of. Can there be sustained peace, dialogue within different religious communities, religion acting as an instrument in maintaining communities that live in and with peace?
A Semi-Empirical Study of the Structural Effects of Ionic Defect Formation in a Model α-Helical System

Recently, there has been a great deal, of interest evidenced in the highly mobile structural defects which occur in hydrogen bonded solids [1, 2]. The type of defect, i. e. Bjerrum or ionic, which occurs in any system depends on which of the Bernal-Fowler rules [3] for the system has been violated. Various properties of mobile defects in hydrogen bonded solids have now been studied, and understanding of their structure and properties is growing rapidly [cf. e. g. 4].
Porcine cancer models: potential tools to enhance cancer drug trials.

Introduction: The amount of time and money invested into cancer drug research, development, and clinical trials has continually increased over the past few decades. Despite record high cancer drug ...
Teaching Medical Epistemology within an Evidence-Based Medicine Curriculum.

Issue: Epistemology, the branch of philosophy that deals with the nature, value, and use of knowledge, receives little or no formal attention in medical education. Yet the understanding of medical ...
Spotting Silent Buffer Overflows in Execution Trace through Graph Neural Network Assisted Data Flow Analysis.

A software vulnerability could be exploited without any visible symptoms. When no source code is available, although such silent program executions could cause very serious damage, the general problem of analyzing silent yet harmful executions is still an open problem. In this work, we propose a graph neural network (GNN) assisted data flow analysis method for spotting silent buffer overflows in execution traces. The new method combines a novel graph structure (denoted DFG+) beyond data-flow graphs, a tool to extract {\tt DFG+} from execution traces, and a modified Relational Graph Convolutional Network as the GNN model to be trained. The evaluation results show that a well-trained model can be used to analyze vulnerabilities in execution traces (of previously-unseen programs) without support of any source code. Our model achieves 94.39\% accuracy on the test data and successfully locates 29 out of 30 real-world silent buffer overflow vulnerabilities. Leveraging deep learning, the proposed method is, to our best knowledge, the first general-purpose analysis method for silent buffer overflows. It is also the first method to spot silent buffer overflows in global variables, stack variables, or heap variables without crossing the boundary of allocated chunks.
Use of hair products in relation to ovarian cancer risk

We evaluated whether hair products, which may contain carcinogens and endocrine disruptors that can be absorbed into the bloodstream, are related to ovarian cancer incidence in a prospective cohort. After excluding women with a history of ovarian cancer or bilateral oophorectomy, 40 559 Sister Study participants ages 35-74 at enrollment (2003-2009) were included. Participants completed questionnaires on hair product use, including hair dyes, straighteners/relaxers and permanents/body waves, in the past 12 months. Cox regression was used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between hair products and incident ovarian cancer. We assessed associations stratified by tumor type (serous, non-serous). Over a mean follow-up of 10 years, 241 women were diagnosed with ovarian cancer. Ever use of any of the examined hair products during the past year was not associated with ovarian cancer risk. However, frequent use (>4 times/year) of straighteners/relaxers or pressing products in the past year was associated with an increased risk of ovarian cancer (HR = 2.19, 95% CI: 1.12-4.27). Ever use of permanent hair dye was positively associated with non-serous (HR = 1.94, 95% CI 1.12-3.37), but inversely associated with serous (HR = 0.65, 95% CI: 0.43-0.99) tumors (p-for-heterogeneity = 0.002). Our novel findings suggest that frequent use of hair straighteners/relaxers or pressing products, which are primarily used by African American/Black women, and possibly permanent hair dye, may be associated with the occurrence of ovarian cancers.
Fatigue Testing of Wearable Sensing Technologies: Issues and Opportunities.

Standards for the fatigue testing of wearable sensing technologies are lacking. The majority of published fatigue tests for wearable sensors are performed on proof-of-concept stretch sensors fabricated from a variety of materials. Due to their flexibility and stretchability, polymers are often used in the fabrication of wearable sensors. Other materials, including textiles, carbon nanotubes, graphene, and conductive metals or inks, may be used in conjunction with polymers to fabricate wearable sensors. Depending on the combination of the materials used, the fatigue behaviors of wearable sensors can vary. Additionally, fatigue testing methodologies for the sensors also vary, with most tests focusing only on the low-cycle fatigue (LCF) regime, and few sensors are cycled until failure or runout are achieved. Fatigue life predictions of wearable sensors are also lacking. These issues make direct comparisons of wearable sensors difficult. To facilitate direct comparisons of wearable sensors and to move proof-of-concept sensors from “bench to bedside”, fatigue testing standards should be established. Further, both high-cycle fatigue (HCF) and failure data are needed to determine the appropriateness in the use, modification, development, and validation of fatigue life prediction models and to further the understanding of how cracks initiate and propagate in wearable sensing technologies.
Small Cell Lung Cancer: Biology Advances

Small-cell lung cancer (SCLC) represents about 13% of all lung cancers and is hallmarked by early metastatic behavior and poor prognosis. Recently immune checkpoint inhibitors have been approved for use in combination with etoposide plus a platinum agent as initial therapy for patients extensive stage SCLC; with the triplet regimen, the median overall survival is approximately 12 months. Over the past 4 years, several agents, including immune checkpoint inhibitors, have also received FDA-approval for SCLC in the relapsed setting, based primarily on objective response rates or duration of response, but not improvement in survival. Analyses of SCLC models have identified molecular subtypes based on the relative expression of key transcriptional regulators. These analyses are leading to a better understanding of SCLC biology and may help identify distinct therapeutic vulnerabilities among subsets of this disease. Ideally, these investigations will lead to more personalized therapeutic approaches and better outcomes for patients diagnosed with this aggressive cancer.
Gene Expression in Lung Epithelial Cells Following Interaction with Pneumocystis carinii and its Specific Life Forms Yields Insights into Host Gene Responses to Infection

Pneumocystis spp. interacts with epithelial cells in the alveolar spaces of the lung. It is thought that the binding of Pneumocystis to host cell epithelium is needed for life cycle completion and proliferation. The effect of this interaction on lung epithelial cells have previously shown that the trophic form of this organism greatly inhibits p34cdc2 activity, a serine/threonine kinase required for transition from G2 to M phase in the cell cycle. To gain further insight into the host response during Pneumocystis pneumonia (PCP), we used microarray technology to profile epithelial cell (A549) gene expression patterns following Pneumocystis carinii interaction. Furthermore, we isolated separate populations of cyst and trophic forms of P. carinii, which were then applied to the lung epithelial cells. Differential expression of genes involved in various cellular functions dependent on the specific P. carinii life form in contact with the A549 cell were identified. The reliability of our data was further confirmed by Northern blot analysis on a number of selected up or down regulated transcripts. The transcriptional response to P. carinii was dominated by cytokines, apoptotic, and anti-apoptotic related genes. These results reveal several previously unknown effects of P. carinii on the lung epithelial cell and provide insight into the complex interactions of host and pathogen.
Peripartum cardiomyopathy: predictors of recovery and current state of implantable cardioverter-defibrillator use.

Objectives The purpose of this study was to identify the predictors of left ventricular (LV) recovery in patients with peripartum cardiomyopathy (PPCM) and to record rates of implantable cardioverter-defibrillator (ICD) use. Background PPCM is a rare, life-threatening disease. The use of ICDs has not been clearly understood in this patient group. Identification of the predictors of persistent LV dysfunction can help select patients at risk for sudden cardiac death. Methods A retrospective study was conducted at 2 academic centers between January 1, 1999, and December 31, 2012. Clinical and demographic variables and delivery records of patients with a diagnosis of PPCM (International Classification of Diseases, 9th Revision code 674.5) were reviewed. Improvement in LV function was noted from echocardiography reports. Results The total sample comprised 100 patients, of whom 55% were African Americans, 39% were Caucasians, and 6% were Hispanic, with a mean age of 30 ± 6 years. Mean left ventricular ejection fraction (LVEF) at diagnosis was 28 ± 9%. Forty-two percent of patients showed improvement in LVEF over a mean duration of 33 ± 21 months. Postpartum diagnosis (hazard ratio: 3.0; p = 0.01) and Caucasian/Hispanic race (hazard ratio: 2.2; p = 0.01) were predictors of improvement in LVEF. Only 7 of the 58 patients (12%) who did not have improvement in their LVEF had an ICD implanted. There were 11 deaths, with a trend toward higher mortality in those who did not display improved LV function (15% vs. 5%; p = 0.1). Conclusions More than one-third of women with PPCM improve LV function with delayed recovery noted in the majority of these patients. Caucasians and those diagnosed in the postpartum period appear to be the most likely to recover. The rate of ICD implantation for primary prevention of sudden cardiac death in this patient group is low.
On universal observability

The authors address the following two questions. What are the algebraic irreducible systems whose external behavior can be described by means of differential algebraic equations only (in which case the external behavior is closed)? Does some specific observability property (called universal observability) imply that external behavior is closed? No complete answers are given. Some partial results are provided. >
Effects of hydrogen sulfide on neurobehavioral function.

Background: Nineteen hydrogen sulfide (H 2 S)-exposed patients were compared with 202 unexposed subjects. This 1997-to-2001 case-referent series was compared with 16 previous (1991-1996) case-referent patients. Methods: New patients were bystanders of H 2 S exposure and none had been unconscious. In contrast, 13 members of the prior group were exposed at work and 7 had been unconscious. The three groups were compared on the basis of 8 physiologic and 12 psychological measurements. Observed measurements were compared with predicted ones after adjusting for age, sex, educational attainment (years), and other significant factors (observed/predicted × 100). Results: The new group performed poorly compared with unexposed controls and were similar to the first group on balance, reaction time, color discrimination, visual performance, hearing, Culture Fair, digit symbol, vocabulary, verbal recall, peg placement, trail making A and B, and information. Conclusion: H 2 S impairments associated with H 2 S were similar in 19 workers (44% had been unconscious) and in 16 bystanders who had not been unconscious.
Amino Acid Side-Chain Contributions to Free Energy of Transfer of Tripeptides from Water to Octanol

The location of amino acids in soluble or membrane proteins is related to the hydrophobicity of the side chains. Amino acid hydrophobicity values are based upon the thermodynamics of transfer from an aqueous to a nonaqueous environment. However, for certain hydrophilic residues uncertainty exists on the appropriate hydrophobicity values. We have measured the octanol-water partition coefficients (Po/w) of tripeptides of the sequence N-14C-acetyl-Ala-X-Ala-NH-tButyl (AcAlaXAlaNHtButyl), where the central residue X was either Gly, Ala, Phe, Trp, Pro, His, Asp, or Glu. The Po/w for the tripeptides agreed reasonably well with values calculated by the fragment method of D. J. Abraham and A. J. Leo (Proteins Struct. Func. Gen. 2, 130-152, 1987). The log Po/w of the uncharged form was 1.6, 2.7, and 2.5 greater than the log Po/w of the ionized form for the His, Asp, and Glu peptide, respectively. The new data on the pH dependence of the ionizable side chains, His, Asp, and Glu, should result in better prediction of the partition coefficient of peptides as a function of pH. The thermodynamic parameters were determined from the temperature dependence of partitioning. In the temperature range studied (2 to 65 degrees C) the transfer of tripeptides from water to octanol was entropy governed except for the ionized peptides. A heat capacity term was necessary to account for the transfer of tripeptides containing non polar residues. The heat capacity change for transfer from water into octanol was -45, -73, -81, and -88 cal/mol K for Ala, Phe, Trp, and Pro peptides, respectively. Peptides containing Gly, His (pH 7.2), and the uncharged forms of Asp, Glu, and His did not show a significant change in heat capacity. The side-chain contribution of the central residue X (delta Gx) to the free energy of transfer was obtained from the difference between the free energy of transfer of the peptide containing the central residue X and the Gly peptide; delta Gx = delta G(AcAlaXAlaNHtButyl) - delta G(AcAlaGlyAlaNHtButyl). The relative order of hydrophobicity of the side chains correlated well with previous studies. However, a significant difference was found for the absolute hydrophobicity between the present study and experimental data on N-acetyl amino acid amide derivatives (J. Fauchere and V. Pliska, Eur. J. Med. Chem. 18(4), 369-375, 1983).(ABSTRACT TRUNCATED AT 400 WORDS)
Pandemic influenza: certain uncertainties

SUMMARY For at least five centuries, major epidemics and pandemics of influenza have occurred unexpectedly and at irregular intervals. Despite the modern notion that pandemic influenza is a distinct phenomenon obeying such constant (if incompletely understood) rules such as dramatic genetic change, cyclicity, “wave” patterning, virus replacement, and predictable epidemic behavior, much evidence suggests the opposite. Although there is much that we know about pandemic influenza, there appears to be much more that we do not know. Pandemics arise as a result of various genetic mechanisms, have no predictable patterns of mortality among different age groups, and vary greatly in how and when they arise and recur. Some are followed by new pandemics, whereas others fade gradually or abruptly into long-term endemicity. Human influenza pandemics have been caused by viruses that evolved singly or in co-circulation with other pandemic virus descendants and often have involved significant transmission between, or establishment of, viral reservoirs within other animal hosts. In recent decades, pandemic influenza has continued to produce numerous unanticipated events that expose fundamental gaps in scientific knowledge. Influenza pandemics appear to be not a single phenomenon but a heterogeneous collection of viral evolutionary events whose similarities are overshadowed by important differences, the determinants of which remain poorly understood. These uncertainties make it difficult to predict influenza pandemics and, therefore, to adequately plan to prevent them. Published 2011. This article is a US Government work and is in the public domain in the USA.
MULTIPLE CONFIGURATION CURVED BRIDGE MODEL STUDIES

In this study, the components of a multiple configuration small-scale horizontally curved bridge were constructed. Using these components, eight different horizontally curved bridge configurations were assembled, analyzed, and tested. In general, the results from analysis and test were sufficiently close to verify the three-dimensional method of analysis and computer program developed at Syracuse University, and the feasibility of using a small-scale multiple configuration model as a research tool to investigate internal forces and displacements in highway bridges. It was also determined that a horizontally curved bridge cannot be effectively analyzed by approximating the curved geometry with chords. If this assumption is made, the analysis will yield internal forces very close to the correct values but will underestimate the deflections of the bridge. Therefore, the stiffness relationship for horizontally curved members subjected to moment, shear, and torsion were derived and incorporated into the three-dimensional analysis and computer program.
An Extremal Property of Turan Graphs

Let ${\cal F}_{n,t_r(n)}$ denote the family of all graphs on $n$ vertices and $t_r(n)$ edges, where $t_r(n)$ is the number of edges in the Turan's graph $T_r(n)$ – the complete $r$-partite graph on $n$ vertices with partition sizes as equal as possible. For a graph $G$ and a positive integer $\lambda$, let $P_G(\lambda)$ denote the number of proper vertex colorings of $G$ with at most $\lambda$ colors, and let $f(n,t_r(n),\lambda) = \max\{P_G(\lambda):G \in {\cal F}_{n,t_r(n)}\}$. We prove that for all $n\ge r\ge 2$, $f(n,t_r(n),r+1) = P_{T_r(n)}(r+1)$ and that $T_r(n)$ is the only extremal graph.
The roles of self‐efficacy and pretest counseling in type 2 herpes simplex virus screening in asymptomatic adults

Purpose: To evaluate the role of counseling for patients undergoing screening for type 2 herpes simplex virus (HSV-2). Using pre- and post-screening questionnaires, we evaluated correlations between demographic factors, measures of self-efficacy and follow-through with the screening test, and willingness to take antiviral medication and share results with sexual partners. Data sources: Subjects (N= 115) were recruited as part of usual care at a private, urban family practice. A total of 111 subjects completed pre-screening questionnaires, and 38 completed post-screening questionnaires. Conclusions: The overwhelming majority of participants were (a) willing to undergo screening; (b) take suppressive antiviral medication if necessary; (c) share their results with sexual partners; and (d) consider safer sexual practices as a consequence of screening. Older patients were less willing to consider daily antiviral medication. Men who have sex with men (MSM) had lower perceived susceptibility to HSV-2 but were more likely to undergo and report screening. Implications for practice: Future research should include predictive models for determining the most appropriate patients to screen for HSV-2 and best practices for those who test positive. Shared decision making between patients and advanced practice nurses regarding the risks and benefits of screening for HSV-2 should be a component visits that include sexually transmitted disease screening. Particular attention should be paid to those at higher risk for contracting the virus, including patients with HIV and MSM.
Generating Enthusiasm among Peer Educators

(1993). Generating Enthusiasm among Peer Educators. Journal of American College Health: Vol. 41, Peer Health Education on Campus, pp. 295-295.
Sharpening Bounds on Principal Effects with Covariates

Estimation of treatment effects in randomized studies is often hampered by possible selection bias induced by conditioning on or adjusting for a variable measured post-randomization. One approach to obviate such selection bias is to consider inference about treatment effects within principal strata, i.e., principal effects. A challenge with this approach is that without strong assumptions principal effects are not identifiable from the observable data. In settings where such assumptions are dubious, identifiable large sample bounds may be the preferred target of inference. In practice these bounds may be wide and not particularly informative. In this work we consider whether bounds on principal effects can be improved by adjusting for a categorical baseline covariate. Adjusted bounds are considered which are shown to never be wider than the unadjusted bounds. Necessary and sufficient conditions are given for which the adjusted bounds will be sharper (i.e., narrower) than the unadjusted bounds. The methods are illustrated using data from a recent, large study of interventions to prevent mother-to-child transmission of HIV through breastfeeding. Using a baseline covariate indicating low birth weight, the estimated adjusted bounds for the principal effect of interest are 63% narrower than the estimated unadjusted bounds.
Increased Production of Tumor Necrosis Factor-α by Glial Cells Exposed to Simulated Ischemia or Elevated Hydrostatic Pressure Induces Apoptosis in Cocultured Retinal Ganglion Cells

Although glial cells in the optic nerve head undergo a reactivation process in glaucoma, the role of glial cells during glaucomatous neurodegeneration of retinal ganglion cells is unknown. Using a coculture system in which retinal ganglion cells and glial cells are grown on different layers but share the same culture medium, we studied the influences of glial cells on survival of retinal ganglion cells after exposure to different stress conditions typified by simulated ischemia and elevated hydrostatic pressure. After the exposure to these stressors, we observed that glial cells secreted tumor necrosis factor-α (TNF-α) as well as other noxious agents such as nitric oxide into the coculture media and facilitated the apoptotic death of retinal ganglion cells as assessed by morphology, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling, and caspase activity. The glial origin of these noxious effects was confirmed by passive transfer experiments. Furthermore, retinal ganglion cell apoptosis was attenuated ∼66% by a neutralizing antibody against TNF-α and 50% by a selective inhibitor of inducible nitric oxide synthase (1400W). Because elevated intraocular pressure and ischemia are two prominent stress factors identified in the eyes of patients with glaucoma, these findings reveal a novel glia-initiated pathogenic mechanism for retinal ganglion cell death in glaucoma. In addition, these findings suggest that the inhibition of TNF-α that is released by reactivated glial cells may provide a novel therapeutic target for neuroprotection in the treatment of glaucomatous optic neuropathy.
Efficiency of an AMTEC Recirculating Test Cell, Experiments and Projections

The alkali metal thermal to electric converter (AMTEC) is an electrochemical device for the direct conversion of heat to electrical energy with efficiencies potentially near Carnot. The future usefulness of AMTEC for space power conversion depends on the efficiency of the devices. Systems studies have projected from 15 to 35 percent thermal to electric conversion efficiencies, and one experiment has demonstrated 19 percent efficiency for a short period of time. Recent experiments in a recirculating test cell (RTC) have demonstrated sustained conversion efficiencies as high as 10.2 percent early in cell life and 9.7 percent after maturity. Extensive thermal and electrochemical analysis of the cell during several experiments demonstrated that the efficiency could be improved in two ways. First, the electrode performance could be improved. The electrode for these tests operated at about one third the power density of state of the art electrodes. The low power density was caused by a combination of high series resistance and high mass flow resistance. Reducing these resistances could improve the efficiency to greater than 10 percent. Second, the cell thermal performance could be improved. Efficiencies greater than 14 percent could be realized through reducing the radiative thermal loss. Further improvements to the efficiency range predicted by systems studies can be accomplished through the development and use of an advanced condenser with improved reflectivity, close to that of a smooth sodium film, and the series connecting of individual cells to further reduce thermal losses.
Spontaneous Oscillation by Hair Bundles of the Bullfrog's Sacculus

One prominent manifestation of mechanical activity in hair cells is spontaneous otoacoustic emission, the unprovoked emanation of sound by an internal ear. Because active hair bundle motility probably constitutes the active process of nonmammalian hair cells, we investigated the ability of hair bundles in the bullfrog's sacculus to produce oscillations that might underlie spontaneous otoacoustic emissions. When maintained in the normal ionic milieu of the ear, many bundles oscillated spontaneously through distances as great as 80 nm at frequencies of 5–50 Hz. Whole-cell recording disclosed that the positive phase of movement was associated with the opening of transduction channels. Gentamicin, which blocks transduction channels, reversibly arrested oscillation; drugs that affect the cAMP phosphorylation pathway and might influence the activity of myosin altered the rate of oscillation. Increasing the Ca 2+ concentration rendered oscillations faster and smaller until they were suppressed; lowering the Ca 2+ concentration moderately with chelators had the opposite effect. When a bundle was offset with a stimulus fiber, oscillations were transiently suppressed but gradually resumed. Loading a bundle by partial displacement clamping, which simulated the presence of the accessory structures to which a bundle is ordinarily attached, increased the frequency and diminished the magnitude of oscillation. These observations accord with a model in which oscillations arise from the interplay of the hair bundle's negative stiffness with the activity of adaptation motors and with Ca 2+-dependent relaxation of gating springs.
Black Women in the Emerging Services Economy.

In the current debate about low-wage work and poverty, little attention has been paid to causes of basic structural change in the economy with the shift from a manufacturing to a services economy. Black women, a key segment of the low-wage work force, have gained and lost in this change. As the lowest paid, lowest status work force in the economy, black women benefited by a move out of domestic services employment where they had been restricted for more than a century. But static wages, high rates of part-time work, and a continuing overconcentration in new but marginal services job systems have created a crisis for personal income and black family support. The growing “feminization of poverty” is the product of growth of a subculture of low-wage work. Only through serious attention to the use of collective bargaining and equal opportunity regulation on behalf of this work force are these trends likely to be reversed in the 1990s.
Orbits homoclinic to resonances: the Hamiltonian case

Abstract In this paper we develop methods to show the existence of orbits homoclinic or heteroclinic to periodic orbits, hyperbolic fixed points or combinations of hyperbolic fixed points and/or periodic orbits in a class of two-degree-of-freedom, integrable Hamiltonian systems subject to arbitrary Hamiltonian perturbations. Our methods differ from previous methods in that the invariant sets (periodic orbits, fixed points) are created, and become hyperbolic, as a result of the interaction of the perturbation with a resonance in the unperturbed system. This results in a very degenerate situation that requires a combination of geometric singular perturbation theory, higher-dimensional Melnikov-type methods, and transversality theory. We establish a simple energy-phase criterion which gives a fairly complete picture of the complex dynamics associated with orbits homoclinic to the resonance. We apply our methods to a two-mode truncation of the driven nonlinear Schrodinger equation first studied by Bishop et al. In this example we show that as the energy is increased at resonance, orbits homoclinic to hyperbolic periodic orbits are created in pairs in a global bifurcation that is best described as a saddle-node bifurcation of homoclinic orbits.
Immunologic characteristics of intrarenal T cells: trafficking of expanded CD8+ T cell β-chain clonotypes in progressive lupus nephritis.

Objective To better define the immunologic character of the T cell infiltrate in lupus nephritis. Methods We performed double immunohistochemical staining and clonotypic T cell receptor (TCR) β-chain sequencing in multiple anatomic regions isolated by laser-capture microdissection from renal biopsy samples. Results Systemic lupus erythematosus (SLE) kidneys have a variably patterned and often extensive infiltrate of predominantly clonally expanded T cells of CD4 and CD8 lineages. CD4+ T cells were prominent in nearly two-thirds of SLE biopsy samples and were distributed as broad periglomerular aggregates or intermixed with CD8+ T cells forming periglomerular caps. Sequencing of the TCR from periglomerular regions showed a predominance of clonally expanded T cells. The CD8+ T cells, which were present in all biopsy samples, often adhered to Bowman's capsule and infiltrated the tubular epithelium. They exhibited features that suggest participation in an adaptive immune response: differentiation into CD28null memory-effector phenotype, trafficking of the same expanded clonotype to different regions of the kidney and to the peripheral blood, and clonal persistence for years in repeat biopsy samples. CD8+ T cell tubulitis was especially associated with progressive changes. Conclusion The immunologic characteristics of the infiltrating CD4+ and CD8+ T cells in the lupus kidney indicate that they have the potential to mediate injury, which may be relevant to development of progressive renal failure. Whereas the oligoclonality of the CD4+ T cell infiltrate is consistent with the paradigm of SLE as a class II major histocompatibility complex–associated autoimmune disease, the finding of CD8+ T cell clonality and trafficking implies participation in a distinct systemic adaptive immune response.
Design and synthesis of 6-oxo-1,6-dihydropyridines as CDK5 inhibitors.

Abstract Cyclin-dependent kinase 5 (CDK5) is a serine-threonine protein kinase that plays a significant role in neuronal development. In association with p25, CDK5 abnormally phosphorylates a number of cellular targets involved in neurodegenerative disorders. Using active site homology and previous structure–activity relationships, a new series of potent CDK5 inhibitors was designed. This report describes the optimization of 6-oxo-1,6-dihydropyridines as CDK5 inhibitors.