cssi/SciSciGPT-SciSciNet huggingface dataset:
Association Between Nonoptimal Blood Pressure and Cochlear Function.

Objectives The association between hearing loss and risk factors for cardiovascular disease, including high blood pressure (BP), has been evaluated in numerous studies. However, data from population- and laboratory-based studies remain inconclusive. Furthermore, most prior work has focused on the effects of BP level on behavioral hearing sensitivity. In this study, we investigated cochlear integrity using distortion product otoacoustic emissions (DPOAEs) in persons with subtle elevation in BP levels (nonoptimal BP) hypothesizing that nonoptimal BP would be associated with poorer cochlear function. Design Sixty individuals [55% male, mean age = 31.82 (SD = 11.17) years] took part in the study. The authors measured pure-tone audiometric thresholds from 0.25 to 16 kHz and computed four pure-tone averages (PTAs) for the following frequency combinations (in kHz): PTA0.25, 0.5, 0.75, PTA1, 1.5, 2, 3, PTA4, 6, 8, and PTA10, 12.5, 16. DPOAEs at the frequency 2f1-f2 were recorded for L1/L2 = 65/55 dB SPL using an f2/f1 ratio of 1.22. BP was measured, and subjects were categorized as having either optimal BP (systolic/diastolic 2 kHz and ≤10 kHz), and high (f2 > 10 kHz) frequency bins] and BP level. Linear mixed-effects models were constructed to account for the effects of BP status, stimulus frequency, age and sex on thresholds, and DPOAE amplitudes. Results Significant positive correlations between diastolic BP and all four PTAs and systolic BP and PTA0.25, 0.5, 0.75 and PTA4, 6, 8 were observed. There was not a significant effect of BP status on hearing thresholds from 0.5 to 16 kHz after adjustment for age, sex, and frequency. Correlations between diastolic and systolic BP and DPOAE levels were statistically significant at the high frequencies and for the relationship between diastolic BP and DPOAE level at the mid frequencies. Averaged across frequency, the nonoptimal BP group had DPOAE levels 1.50 dB lower (poorer) than the optimal BP group and differences were statistically significant (p = 0.03). Conclusions Initial findings suggest significant correlations between diastolic BP and behavioral thresholds and diastolic BP and mid-frequency DPOAE levels. However, adjusted models indicate other factors are more important drivers of impaired auditory function. Contrary to our hypothesis, we found that subtle BP elevation was not associated with poorer hearing sensitivity or cochlear dysfunction. We consider explanations for the null results. Greater elevation in BP (i.e., hypertension itself) may be associated with more pronounced effects on cochlear function, warranting further investigation. This study suggests that OAEs may be a viable tool to characterize the relationship between cardiometabolic risk factors (and in particular, stage 2 hypertension) and hearing health.
Selective transport of fluorescent proteins into the phage nucleus

Upon infection of Pseudomonas cells, jumbo phages 201{Phi}2-1, {Phi}PA3, and {Phi}KZ assemble a phage nucleus. Viral DNA is enclosed within the phage-encoded proteinaceous shell along with proteins associated with DNA replication, recombination and transcription. Ribosomes and proteins involved in metabolic processes are excluded from the nucleus. RNA synthesis occurs inside the phage nucleus and messenger RNA is presumably transported into the cytoplasm to be translated. Newly synthesized proteins either remain in the cytoplasm or specifically translocate into the nucleus. The molecular mechanisms governing selective protein sorting and nuclear import in these phage infection systems are currently unclear. To gain insight into this process, we studied the localization of five reporter fluorescent proteins (GFP+, sfGFP, GFPmut1, mCherry, CFP). During infection with {Phi}PA3 or 201{Phi}2-1, all five fluorescent proteins were excluded from the nucleus as expected; however, we have discovered an anomaly with the {Phi}KZ nuclear transport system. The fluorescent protein GFPmut1, expressed by itself, was transported into the {Phi}KZ phage nucleus. We identified the amino acid residues on the surface of GFPmut1 required for nuclear targeting. Fusing GFPmut1 to any protein, including proteins that normally reside in the cytoplasm, resulted in transport of the fusion into the nucleus. Although the mechanism of transport is still unknown, we demonstrate that GFPmut1 is a useful tool that can be used for fluorescent labelling and targeting of proteins into the {Phi}KZ phage nucleus.
On the Validity of Machine Learning-based Next Generation Science Assessments: A Validity Inferential Network

This study provides a solid validity inferential network to guide the development, interpretation, and use of machine learning-based next-generation science assessments (NGSAs). Given that machine learning (ML) has been broadly implemented in the automatic scoring of constructed responses, essays, simulations, educational games, and interdisciplinary assessments to advance the evidence collection and inference of student science learning, we contend that additional validity issues arise for science assessments due to the involvement of ML. These emerging validity issues may not be addressed by prior validity frameworks developed for either non-science or non-ML assessments. We thus examine the changes brought in by ML to science assessments and identify seven critical validity issues of ML-based NGSAs: potential risk of misrepresenting the construct of interest, potential confounders due to that more variables may involve, nonalignment between interpretation and use of scores and designed learning goals, nonalignment between interpretation and use of scores and actual learning quality, nonalignment between machine scores and rubrics, limited generalizable ability of machine algorithmic models, and limited extrapolating ability of machine algorithmic models. Based on the seven validity issues identified, we propose a validity inferential network to address the cognitive, instructional, and inferential validity of ML-based NGSAs. To demonstrate the utility of this network, we present an exemplar of ML-based next-generation science assessments that was developed using a seven-step ML framework. We articulate how we used the validity inferential network to ensure accountable assessment design, as well as valid interpretation and use of machine scores.
Improving the Care of Patients With Serious Illness: What Are the Palliative Care Education Needs of Internal Medicine Residents?

Background:Hospitalized patients with serious illness have significant symptom burden and face complex medical decisions that often require goals of care discussions. Given the shortage of specialt...
15 Years of Research on US Employment and the Minimum Wage

Statistical analysis of the minimum wage and employment has been very active for the last quarter century, including more than 37 studies of US data since the December 2000 AER exchange involving Card, Krueger, Neumark and Wascher. In this meta‐analysis of the 37 that report results suitable for this technique, the most important finding is a considerable shift toward the origin in the ‘consensus range’: from the interval [−0.3, −0.1] to [−0.13, −0.07]. The minimum wage has negative employment effects, but these have become notably smaller and are largely localized to teenagers.
Decolonizing ethnography: undocumented immigrants and new directions in social science: by Carolina Alonso Bejarano, Lucia López Juárez, Mirian A. Mijangos García, and Daniel M. Goldstein, Durham, NC, Duke University Press, 2019, xiii+183pp., $24.95 (paperback), ISBN 1478003626

How can anthropology be an instrument for progressive social change? Ethnographers have long grappled with this question, battling our colonial legacies and grasping for more embedded, activist wor...
Aneurysmal Subarachnoid Hemorrhage: Review of the Pathophysiology and Management Strategies

Aneurysmal subarachnoid hemorrhage remains a devastating disease process despite medical advances made over the past 3 decades. Much of the focus was on prevention and treatment of vasospasm to reduce delayed cerebral ischemia and improve outcome. In recent years, there has been a shift of focus onto early brain injury as the precursor to delayed cerebral ischemia. This review will focus on the most recent data surrounding the pathophysiology of aneurysmal subarachnoid hemorrhage and current management strategies. There is a paucity of successful trials in the management of subarachnoid hemorrhage likely related to the targeting of vasospasm. Pathophysiological changes occurring at the time of aneurysmal rupture lead to early brain injury including cerebral edema, inflammation, and spreading depolarization. These events result in microvascular collapse, vasospasm, and ultimately delayed cerebral ischemia. Management of aneurysmal subarachnoid hemorrhage has remained the same over the past few decades. No recent trials have resulted in new treatments. However, our understanding of the pathophysiology is rapidly expanding and will advise future therapeutic targets.
Structure-activity relationships for 5F-MDMB-PICA and its 5F-pentylindole analogs to induce cannabinoid-like effects in mice.

Synthetic cannabinoid receptor agonists (SCRAs) are an evolving class of new psychoactive substances found on recreational drug markets worldwide. The indole-containing compound, 5F-MDMB-PICA, is a popular SCRA associated with serious medical consequences, including overdose and hospitalizations. In vitro studies reveal that 5F-MDMB-PICA is a potent agonist at cannabinoid type 1 receptors (CB1), but little information exists regarding in vivo pharmacology of the drug. To this end, we examined the in vitro and in vivo cannabinoid-like effects produced by 5F-MDMB-PICA and related 5F-pentylindole analogs with differing composition of the head group moiety (i.e., 5F-NNEI, 5F-SDB-006, 5F-CUMYL-PICA, 5F-MMB-PICA). In mouse brain membranes, 5F-MDMB-PICA and its analogs inhibited binding to [3H]rimonabant-labeled CB1 and displayed agonist actions in [35S]GTPγS functional assays. 5F-MDMB-PICA exhibited the highest CB1 affinity (Ki = 1.24 nM) and functional potency (EC50 = 1.46 nM), but head group composition markedly influenced activity in both assays. For example, the 3,3-dimethylbutanoate (5F-MDMB-PICA) and cumyl (5F-CUMYL-PICA) head groups engendered high CB1 affinity and potency, whereas a benzyl (5F-SDB-006) head group did not. In C57BL/6J mice, all 5F-pentylindole SCRAs produced dose- and time-dependent hypothermia, catalepsy, and analgesia that were reversed by rimonabant, indicating CB1 involvement. In vitro Ki and EC50 values were positively correlated with in vivo ED50 potency estimates. Our findings demonstrate that 5F-MDMB-PICA is a potent SCRA, and subtle alterations to head group composition can have profound influence on pharmacological effects at CB1. Importantly, measures of CB1 binding and efficacy in mouse brain tissue seem to accurately predict in vivo drug potency in this species.
Algebra in ancient and modern times

Some history of early mathematics: Eucild-Archimedes-Diophantus Pythagoras and the Pythagorean triplets Aryabhata-Brahmagupta-Bhaskara Irrational numbers: construction and approximation Arabic mathematics Beginnings of algebra in Europe The cubic and biquadratic equations Solution of the cubic and biquadratic equations: Solution of the cubic equation Solution of the biquadratic equation Some themes from modern algebra: Numbers, algebra, and the real world Complex numbers Fundamental theorem of algebra Equations of degree greater than four General number systems and the axiomatic treatment of algebra References Chronology Index.
The CRAY S-MP architecture: seamless vector and parallel processing in a SPARC environment

The CRAY S-MP architecture, which provides a single system image for scalar, vector, and highly parallel processing modules, is described. System configuration can vary according to resource requirements to address high-performance computing as well as mass storage and visualization applications. A common programming environment, common tools and libraries, and fast network access allow the system to take a large step toward integrated network supercomputing. >
Hyperspectral and multispectral imaging in the food and beverage industries.

Abstract: This chapter presents hyperspectral and multispectral imaging technologies in the food and agricultural area. It puts emphasis on the introduction and demonstration of spectral imaging techniques for practical uses. The main topics include spectral image acquisition methods, essential components for building spectral imaging systems (e.g., light sources, wavelength dispersive devices and area detectors), methods for calibrating spectral imaging systems (e.g., spectral and spatial calibrations) and techniques for analyzing spectral images (e.g., data preprocessing, dimension reduction and band selection). The spectral imaging applications for evaluating food and beverage products are also presented.
Computational modeling and simulation of heart ventricular mechanics from tagged MRI

Heart ventricular mechanics has been investigated intensively in the last four decades. The passive material properties, the ventricular geometry and muscular architecture, and the myocardial activation are among the most important determinants of cardiac mechanics. The heart muscle is anisotropic, inhomogeneous, and highly nonlinear. The heart ventricular geometry is irregular and object dependent. The muscular architecture includes the organization of the fiber and the connective tissues. Studies of the myocardial activation have been carried out at both cell and tissue levels. Previous work from our research group has successfully estimated the in-vivo motion and deformation of both the left and the right ventricles. In this paper, we present an iterative model to estimate the in-vivo myocardium material properties, the active forces generated along fiber orientation, and strain and stress distribution in both ventricles. Compared to the strain energy function approach, our model is more intuitively understandable. Using the model, we have simulated the mechanical events of a few different heart diseases. Noticeable strain and stress differences are found between normal and diseased hearts.
Enantiomeric Purity Studied Using NMR

Methods for estimating the proportions of enantiomers (enantiomeric excess) in a sample and determining the absolute stereochemistry of compounds using NMR spectroscopy are described. These comprise the use of chiral derivatizing agents, solvating agents, metal complexes and liquid crystals. Examples of each approach are given.
Evaluation of Lifetime Performance of Hi-Nicalon™ Fiber-Reinforced Melt-Infiltrated SiC Ceramic Composites

Evaluation of lifetime performance of Hi-Nicalon fiber-reinforced SiC ceramic composites was carried out in four-point bending over a temperature range of 700° to 1300°C in air. The effects of number of harness and type of coating on the lifetime response were also evaluated in the present study. The composites consisted of ∼40 vol. % Hi-Nicalon fiber (8 or 5 harness satin weave) with a 0.5 μm BN (or C) fiber coating and a melt-infiltration SiC ceramic matrix. Lifetime results indicated that the Hi-Nicalon/MI SiC composites exhibited a stress-dependent lifetime at stress levels above an apparent fatigue limit, similar to the trend observed in CG-Nicalon fiber-reinforced CVI SiC matrix composites. The observed stress-dependent lifetime behavior was independent upon the number of harness and type of coating employed. However, results indicated that the lifetime performance of Hi-Nicalon/MI SiC composites could be greatly enhanced via the use of a higher number of harness satin weave and/or BN fiber coating. For SiC composites with BN fiber coating at temperatures 1150°C the lifetime performance of SiC composites was limited by the onset of creep of Hi-Nicalon fibers. The lifetime governing processes in an oxidizing environment were generally attributed to the progressive oxidation of fiber coatings and subsequent formation of glassy phase(s), which formed a strong bond between fiber and matrix, resulting in embrittlement of the composite with time.
Whole-mount electron microscopy of chromatin and membranes in bull and human sperm heads.

The fine structure of bull and human sperm nuclei and membranes was studied by treating unsectioned spermatozoa with alkaline thioglycolate and drying by the Anderson critical point method. The nucleus of bull and human sperm, in an unpacked state, is composed of a network of chromatin fibers. Single fibers range from 140 to 240 A in diameter and exhibit possible cross fibers or branches. Lengths of measured fibers could be traced for at least 12μ. Three components of an outer membrane system were distinguished in bull sperm after thioglycolate treatment. The human sperm membranes were found to be more labile to thioglycolate treatment.
Protein Kinase Cθ Modulates Nuclear Receptor-Corepressor Interaction during T Cell Activation

Transcriptional repression by nuclear receptor corepressors plays a critical role in T cell development. However, the role of these corepressors in T cell activation is poorly understood. We report that T cell activation silenced transcription driven by nuclear receptors retinoic acid receptor, retinoid X receptor, and thyroid hormone receptor and induced silencing mediator of retinoic acid and thyroid hormone receptors (SMRT)-receptor interaction. Whereas the expression of a dominant active mutant of protein kinase C theta(PKC theta) induced strong SMRT-receptor interaction in the absence of T cell activation, a dominant negative mutant of PKC theta decreased the interaction. Loss of PKC theta expression by induction of "RNA interference" resulted in the attenuation of basal and activation-induced SMRT-receptor interaction. We suggest that T cell activation silences nuclear receptor-dependent transactivation in part through PKC theta-dependent enhancement of SMRT-receptor interaction.
Oxygen transport properties of liquid crystalline poly(pentamethylene 4,4′-bibenzoate)

Abstract This study examined the solid state structure and oxygen transport properties of smectic poly(pentamethylene 4,4′-bibenzoate) (PP5BB). The polymer was quenched from the isotropic melt to the smectic liquid crystalline (LC) glass and subsequently isothermally crystallized above the glass transition temperature. Crystallized PP5BB was characterized by thermal analysis and X-ray diffraction. Gas transport properties were characterized at 23 °C and 1 atm pressure. Examination of the smectic LC glass by atomic force microscopy (AFM) revealed a hierarchical structure in which mesogens organized into smectic layers, stacks of layers formed wavy lamellae, and assembles of lamellae defined domains. The effect of crystallization on the oxygen transport properties supported a simple two-phase model of impermeable crystallites dispersed in a permeable smectic glass. Due to the low-crystallite aspect ratio, crystallization only slightly increased the tortuosity of the diffusion pathway. This result provided the structural basis for describing oxygen permeability in terms of the Nielsen model for low-aspect ratio particles. The hierarchical LC structure of PP5BB closely resembled that reported for poly(diethylene glycol 4,4′-bibenzoate) (PDEGBB), which has the same chemical structure as PP5BB except that the center methylene of the spacer is replaced with an ether oxygen. However, oxygen permeability of PP5BB was about three times higher than that of PDEGBB. Non-LC aromatic polyesters with pentamethylene diol spacers also had oxygen permeability about three times higher than the corresponding polyester with diethylene glycol spacers due primarily to higher diffusivity. The effect was traced to differences in the sub-ambient mechanical relaxation behavior.
A speculative approach to parallelization in particle swarm optimization

Particle swarm optimization (PSO) has previously been parallelized primarily by distributing the computation corresponding to particles across multiple processors. In these approaches, the only benefit of additional processors is an increased swarm size. However, in many cases this is not efficient when scaled to very large swarm sizes (on very large clusters). Current methods cannot answer well the question: “How can 1000 processors be fully utilized when 50 or 100 particles is the most efficient swarm size?” In this paper we attempt to answer that question with a speculative approach to the parallelization of PSO that we refer to as SEPSO.
Heat treatment of cold extruded polycarbonate: Some implications for design engineers

Abstract Polycarbonate was subjected to various combinations of mechanical - thermal histories to investigate such effects on subsequent tensile mechanical properties. This was accomplished by “cold extruding” the material initially; nominal “reductions in area” of 18, 40 and 64% were used. Cold extruded bars were then heat treated at three temperature levels, all being less than T g (150°C) of polycarbonate. As compared with the material that was only cold extruded, it was found that in general, heat treating tends to raise the yield stress while lowering the tensile strength, elastic modulus and stress at fracture. The results suggest that a desired combination of properties may be obtainable by the use of a cold work - heat treating sequence.
Mediating cultural borders during science field trips

In this paper, I analyze teacher and student roles in the teaching and learning of science at an informal learning center, The Outdoor Classroom. As a white middle class informal learning science teacher, I examine my struggles to teach science to students across boundaries of race, class, gender, and experience with the outdoors during field trips. Through the field trip I did not have the time or face-to-face experience to make sense of the students’ culture, see their culture in terms of capital, and align my enactment to benefit their learning. Likewise, the students did not have the time or face-to-face experience with me in order to adapt their cultural capital and build the essential stocks of symbolic and social capital. This research demonstrates how the classroom teacher draws upon previous transactions and emotions to successfully engage her students in practices that promote the participation and learning of science. Through creating culturally adaptive ways of transacting, teachers can provide opportunities for their students to generate positive emotional energy and group solidarity in the learning of science at an informal science center.
Applications Of Scanning Continuous Wave (CW) And Pulsed Lasers In Silicon Technology

Both pulsed and scanning cw lasers operating at wavelengths in the range 0.5-1.06 μm can be used as a method to rapidly heat the surface and underlying bulk of a semiconductor material to a precisely controlled temperature up to melting. As a result, lasers can be utilized to anneal ion-implanted layers, reduce fixed interface charge of deposited oxide films, grow surface oxides, react metal/silicon layers to form silicides and improve and control the electrical properties of deposited silicon films.© (1980) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Social financial reporting in India: A case

Abstract Social accounting in company annual reports within the framework of a socialistic pattern of industrial development is discussed. A public sector company (Steel Authority of India Limited) is examined with regard to the type, form, and content of social financial disclosures. Students are asked several questions about social accounting in India and in general. This case can be used in an Accounting Theory, Issues, or International course at the undergraduate or graduate level.
Automatic crest line extraction from anatomical surfaces

Crest lines are shape features with high significance on anatomical surfaces. They implicitly follow the gyri and the fundi of sulci on the cerebral cortex. In this work, an automatic crest line extraction algorithm is presented and show two useful applications, rigid registration and surface simplification.
901-73 Geographic Variation in the Utilization of Pacemaker Technology

The goal of this study was to identify differences in perc a pita rates of single and dual-chamber pacemaker implantation and rates of implantation for a given conduction disorder at the county level in the State of California. Significant geographic variation has been documented in the use of coronary angiography and coronary artery bypass surgery. We used a large database, the California Discharge Database, during the years 1984-1992 to identify the diagnostic codes of patients at risk (complete heart block, Mobitz II block, sinoatrial dysfunction, and other heart block) for a single or dual-chambered pacemaker in the twelve most populous counties. Rates were calculated by identifying patients from a given county who received a pacemaker and dividing by the county population in age groups ‘65-80’ and ‘over 80’, while controlling for a given diagnostic code. These aged groups captured 79% of all implants (N = 2827 in 1984). Implantation rates per diagnosis were also calculated for a given county. There was variability in implantation rates among large counties in California with greater than 100 pacemaker implants in 1984 and 1985. The overall (ventricular + atrioventricular) rate, by county, was significantly different in the population groups ‘65-80’ (p l 0.005) and ‘over 80’ (p l 0.0005). If atrial pacemakers were included in the analysis, the differences in rates persisted; ‘65-80’ (p l 0.005) and ‘over 80’ (p l 0.002). For dual chamber implants only there also was significant variability in both the 65-80 and g80 aged groups (p l 0.00011 among counties. There also was significant variability in the ratio of dual to single-chamber pacemakers by county in both age groups (p l 0.0005). Conclusion Initial data using a comprehensive database has identified geographic variability in county rates of pacemaker implantation independent of diagnosis. This geographic variation in utilization may represent physician uncertainty in the use of pacemaker technology.
catena-Poly[2,2′,2′′-nitrilo­tris­(ethan­aminium) [tri-μ-oxido-tris­[dioxido­vanadate(V)]] monohydrate]

The title compound, {(C6H21N4)[V3O9]·H2O}n, crystallizes as a salt with [trenH3]3+ cations [tren is tris­(2-amino­eth­yl)amine], and one-dimensional anionic {[VVO3]−}n (metavanadate) chains along the c-axis direction. Three crystallographically distinct VV sites and one occluded water mol­ecule are present for every [trenH3]3+ cation in the unit cell. The {[VVO3]−}n chains are composed of vertex-sharing [VO4] tetra­hedra and have a repeat unit of six tetra­hedra. Each tetra­hedron in the chain contains two terminal and two μ2-bridging oxide ligands. The [trenH3]3+ cations, {[VVO3]−}n anions and occluded water mol­ecules participate in an extensive three-dimensonal hydrogen-bonding network. The three terminal ammonium sites of the [trenH3]3+ cations each form strong N—H⋯O hydrogen bonds to terminal oxide ligands on the {[VVO3]−}n chain. Each occluded water mol­ecule also donates two O—H⋯O hydrogen bonds to the terminal oxide ligands.
A note on psychophysical measures

The nature of liminal measurement is discussed, and the standard deviation is proposed asa suitable alternative measure to the limen.
Recent developments in the application of the Generalized Acoustic Analogy to jet noise prediction

The Generalized Acoustic Analogy provides a logical framework for the prediction of aerodynamically generated sound. This paper reviews some recent developments in the use of this analogy for the prediction of noise from high speed air jets. Other approaches to jet noise prediction are not discussed. Recent advances in accounting for non-parallel mean flow and temperature effects are described. The results suggest that the former effect is more important than previously believed. They also suggest that previously neglected coupling between momentum flux and enthalpy flux fluctuations can be an important source of noise in high Mach number heated jets. Some recent improvements in acoustic source modeling are also summarized.
Effects of subchronic administration of soman on acquisition of avoidance-escape behavior by laboratory rats.

Abstract Holtzman male Sprague-Dawley rats were given four injections of saline or soman at 31 μu/kg or 46 μ/kg. The injections were given every 3 days during a 2-week period. Tail vein blood samples, drawn 24 hr before the first injection and 24 hr after the last injection, were analyzed for acetylcholinesterase (AChE) inhibition. For the low and high soman groups, whole blood AChE was inhibited 20 and 24%, respectively, while plasma AChE was inhibited 17 and 25%, respectively. Parallel saline injections produced a small inhibition of whole blood AChE and an increase in activity (negative inhibition) of plasma AChE. During the second week of soman administration rats began training on a discriminated shock avoidance task. The seven animals administered 46 μg/kg soman did not learn the lever-pressing avoidance response during a period of 120 days. Five of eight saline rats and four of seven 31 μg/kg soman rats learned the avoidance response. There was no significant difference between learners relative to rat of learning of the avoidance task. All of the rats learned to escape the shocks. These data indicate that subchronic soman inhibits learning of new behaviors by laboratory rats.
Transforming growth factors and related peptides in gastrointestinal neoplasia

Transforming growth factor alpha and beta 1 (TGF alpha and TGF beta 1) are representative members of two distinct and expanding families of polypeptide growth factors. TGF alpha is an epithelial cell mitogen, whereas TGF beta 1 inhibits epithelial cell growth; the role of these factors in contributing to the transformed phenotype is uncertain. Steady state mRNA expression for these growth factors and their receptors in a panel of human colon cancers and adjacent normal mucosa is presented. Based in part on results from transgenic mice in which TGF alpha is selectively overproduced in the mammary gland, a possible role for TGF alpha as a tumor promoter in the process of transformation is discussed.
The plumbing of minimal area surfaces

Abstract We study the metric of minimal area on a punctured Riemann surface under the condition that all nontrivial homotopy closed curves be longer than or equal to 2π. By constructing deformations of admissible metrics we establish necessary conditions on minimal area metrics and a partial converse to Beurling's criterion for extremal metrics. We explicitly construct new minimal area metrics that do not arise from quadratic differentials. Under the physically motivated assumption of existence of the minimal area metrics, we show there exist neighborhoods of the punctures isometric to a flat semi-infinite cylinder of circumference 2π, allowing the definition of canonical complex coordinates around the punctures. The plumbing of surfaces with minimal area metrics is shown to induce a metric of minimal area on the resulting surface. This implies that minimal area string diagrams define a consistent quantum closed string field theory.
Optimal input sets for steering quantized systems

Limited capacity of communication channels has strongly pushed the analysis of control systems subject to a quantized input set. Quantized control system of type x + = x + u, where the u takes values in a set of 2m + 1 integer numbers, symmetric with respect to 0 arise in some fundamental situations, e.g., flat, nilpotent, and linear systems with quantized feedback. In this paper we consider this special type of systems and analyze the reachable set after K steps. We find explicit expressions, for each K and for each m, of m input values such that the reachable set after K steps is as large as possible.
Gamma Rays from Interaction of 14-Mev Neutrons with Various Materials

Experiments have been performed to observe the pulse-height distribution produced in a single crystal spectrometer by gamma radiation arising from bombardment of various materials with 14-Mev neutrons. Various gamma-ray lines have been identified and estimates made of the total cross section for gamma-ray production.
The role of multidrug efflux pumps in the antibiotic resistance of Pseudomonas aeruginosa and other gram-negative bacteria. Insights from the Society of Infectious Diseases Pharmacists.

Gram-negative bacteria remain clinically important pathogens in both hospital and community settings. Recent research indicates that efflux pumps play a prominent role in the multidrug resistance of Pseudomonas aeruginosa and many other gram-negative bacteria. Four multidrug efflux pump systems have been well characterized in P. aeruginosa: MexA-MexB-OprM, MexC-MexD-OprJ, MexE-MexF-OprN, and MexX-MexY-OprM. These efflux pumps have different substrate specificities, and their production and activity can be increased by many factors commonly present in infections (e.g., high inocula of bacteria, low pH, and stationary-phase growth). Moreover, fluoroquinolone antibiotics can commonly select mutants that constitutively overproduce Mex-Opr efflux pump systems. Based on most recent studies, the prevalence of efflux pump overproduction in clinical strains of P. aeruginosa may range from 14–75%. The best treatment for infections caused by bacteria that overproduce efflux pumps is unknown, but pharmacodynamic optimization of antibiotics and the use of antibiotic combinations that are substrates for different pump systems may represent reasonable strategies until more data are available.
Evaluation of selected ultralight manual wheelchairs using ANSI/RESNA standards.

Abstract Objectives: To provide data for clinicians and wheelchair users to compare the durability, strength, stability, and cost effectiveness of four different ultralight wheelchair models, and to compare the results of this study with those published for lightweight wheelchairs. Design: Standards testing and cost-effectiveness analysis of four wheelchair models from different manufacturers (12 wheelchairs total). Results: There were significant differences ( p ≤ .05) in the fatigue life and value (equivalent cycles per dollar) among the ultralight wheelchairs tested. There was also a significant difference ( p ≤ .05) in rearward stability tilt angle for the least and most stable configurations. There were no differences in forward and lateral stability. The ultralight wheelchairs (1,009,108 cycles) had significantly ( p ≤ .05) higher fatigue lives than previously reported for lightweight wheelchairs (187,370 cycles). The lightweight wheelchairs had a mean value of 210 cycles per dollar compared to 673 cycles per dollar for the ultralight wheelchairs. The difference in value for the lightweight and ultralight wheelchairs was statistically significant ( p ≤ .05). Conclusion: There were differences in the fatigue life and value among the four models of ultralight manual wheelchairs tested. This indicates that ultralight manual wheelchairs are not all of equal quality. The fatigue life and value of the ultralight manual wheelchairs were significantly higher than those previously reported for lightweight manual wheelchairs. This indicates that ultralight wheelchairs may be of higher quality than lightweight manual wheelchairs. Clinicians and consumers should seriously consider selecting an ultralight manual wheelchair to meet their wheelchair mobility needs.
Tumoral calcinosis, diaphysitis, and hyperphosphatemia

Three children with hyperphosphatemic tumoral calcinosis, including 2 siblings, presented with recurrent pain and swelling of the legs. Laboratory tests, radiographs, and biopsy showed reactive new bone formation of unknown etiology in the diaphyses. The authors hypothesize a relationship between tumoral calcinosis, hyperostosis, and hyperphosphatemia and consider possible mechanisms.
Re-evaluation of spectrophotometric standard reference materials for additional geometries and wavelengths

ABSTRACT Two types of mirrors and a glass are used as Standard Reference Materials to calibrate the specular reflectance scales ofoptical systems. While calibrations of these materials are routinely performed using the 6°/6° geometry, there has been anincreased interest in the optical radiation measurement community for additional bidirectional geometries such as 300/300and 45°/45°. This paper reports the results of specular reflectance measurements of first surface aluminum and gold mirrorsand polished black glass at wavelengths from 250 am to 2250 nm. Supplemental measurements of wavelength standards areincluded to provide a comprehensive overview ofthe standards available for calibrating spectrophotometers.Keywords: aluminum mirror, black glass, gold mirror, specular reflectance, standard reference materials, wavelengthstandards 1. INTRODUCTION The needs of optical engineers and optical component manufacturers provided the initial motivation for the development ofspecular reflectance standards. The additional requirements of gonioapparent building materials, automotive paints andcoatings, graphical arts, and the semiconductor industry have provided the impetus for further studies of specular reflectanceusing a bidirectional geometry. Specular reflectance Standard Reference Material's (SRM's) currently availiable from theNational Institute of Standards and Technology (NIST) are first and second surface aluminum mirrors, first surface goldmirrors, and a polished black glass. Specular reflectors are prepared by using several methods such as evaporating metalonto glass substrates, electroplating, polishing or diamond turning metal. Each method seeks to produce a robust coatedsurface that will meet long-term stability, durability, and uniformity assessments. Although none of coatings thus far hasproven to be robust, the solution may be found in new techniques such as diamond turning metals and electron or sputteringdeposition of metals. Survey measurements were performed on two different types of materials to determine their suitability
Erythroid-specific transcription of the chicken histone H5 gene is directed by a 3′ enhancer

The expression of a variety of vertebrate genes is transcriptionally regulated through tissue-specific cellular enhancer elements1. An erythroid-specific enhancer sequence has recently been identified 3′ to (downstream of) the chicken adult β-globin gene2,3. Here we report the identification of a second erythroid-specific enhancer sequence, which is 3′ to the chicken histone H5 gene. The similarity of these two enhancer elements, with respect both to function and location relative to the target gene, implies some functional conservation in their evolution and in the mechanism by which they affect erythroid gene transcription.
Numerical simulation of load-induced bone structural remodelling using stress-limit criterion.

A simple and efficient numerical method for predicting the remodelling of adaptive materials and structures under applied loading was presented and implemented within a finite element framework. The model uses the trajectorial architecture theory of optimisation to predict the remodelling of material microstructure and structural organisation under mechanical loading. We used the proposed model to calculate the density distribution of proximal femur in the frontal plane. The loading considered was the hip joint contact forces and muscular forces at the attachment sites of the muscles to the bone. These forces were estimated from a separate finite element calculation using a heterogeneous three-dimensional model of the proximal femur. The density distributions obtained by this procedure has a qualitative similarity with in vivo observations. Solutions displayed the characteristic high-density channels that are evident in the Dual X-ray Absorptiometry scan. There is also evidence of the intramedullary canal...
Habitual physical activity and serum lipids: males, age 16-64 in a total community.

Abstract More than 1000 males were classified into one of three groups (active, moderately active or sedentary) on the basis of their occupation and leisure time activity. This was done in age specific groups to eliminate the influence of age in the analyses. Blood samples were drawn from these subjects in a non-fasting state. Total cholesterol and triglycerides concentration were determined. Serum cholesterol and, to a lesser extent, serum triglycerides were lower in the active subjects. Diet did not account for the differences. The question was then raised whether the activity-serum relationships would persist if corrected for body fatness of the subjects. The sum of four skinfolds was available as a measure of body fatness. The sum of skinfolds was significantly related to inactivity and the concentration of cholesterol and triglycerides. When corrected for body fatness, there appeared to be little relationship between physical activity and serum lipids.
The envelope following response: scalp potentials elicited in the Mongolian gerbil using sinusoidally AM acoustic signals.

Abstract Scalp potentials which follow the low frequency envelope of a sinusoidally amplitude modulated stimulus waveform were evoked and recorded in anesthetized gerbils. This envelope following response (EFR) is presumably due to the synchronized discharge of populations of neurons in the auditory pathway. The magnitude of the EFR increased and the latency decreased in a near monotonic fashion with increased stimulus intensity and modulation depth. The modulation rate transfer function (MRTF) was determined for modulation frequencies between 10 and 920 Hz imposed on carrier frequencies ranging from 1 to 7 kHz. The MRTF was low pass in character having a corner frequency of 100–120 Hz. Measurements of the group delay, determined from the phase of the response relative to the stimulus phase, indicate that the response is generated in at least three distinct regions within the auditory pathway.
AK Herculis — An atypical W UMa-type system

AK Herculis is a contact binary of spectral class F with a number of obvious peculiarities such as a displacement of secondary eclipse from phase 0 . P 500, unequal heights of the maxima, and a possibly sinusoidal (≃60 yr) period variation. The light curve is variable and shows erratic short-term behavior, although the latter effects are not unusual for a short period contact binary. Here we present new photoelectric light curves in theB andV passbands and derive several new times of minima. The new observations are compared graphically with seven earlier light curves. We analyzed the new observations and those by Bookmyer (1972) by the method of differential corrections. We find that the temperature difference between components is too large (≃1000 K) for AK Her to be considered a normal W UMa-system, but too small to allow a detached configuration obeying the mass-luminosity law. The solutions of both series of observations clearly indicate a contact configuration. Other unusual findings include a bolometric albedo greater than 2, and rather low values for the limb-darkening coefficients. We offer some possible reasons for these peculiarities. The mass ratio seems well determined from the photometry and is about 0.26, which is much lower than assumed in most earlier papers. The brightness and color of the known visual companion, ADS 10408B, were found by the differential corrections program. They agree, within observational error, with values found directly at the 200-in. telescope by Eggen, despite the fact that the B component contributes only a few percent of the light of the multiple system. The suggestion by Schmidt and Herczeg (1959) that a fourth body is responsible for the sinusoidal period variation seems stronger now than when first proposed. To encourage a search for this hypothetical component, we have tabulated expected values for its angular separation and relative mass with respect to the eclipsing pair, as well as the amplitude of the expected variable proper motion of the eclipsing pair. Discovery as a visual component seems impossible with present means, but the variable proper motion should be detectable. Thus we suggest that ADS 10408A (AK Her) be observed astrometrically. If a search for the predicted variable proper motion proves negative, mass transfer would remain the only plausible mechanism to explain the period change. We advance a different reason than did Schmidt and Herczeg to explain the phase lag of secondary eclipse.
Development and Validation of an Instrument to Measure Maturity of IT Business Strategic Alignment Mechanisms

Achieving IT-business alignment has been a long-standing, critical, information management issue. A theoretical framework of the maturity levels of management practices and strategic IT choices that facilitate alignment was empirically tested and validated. Confirmatory factor analysis CFA validated 6 factors and identified 22 indices to measure strategic alignment maturity. A mixed model repeated measure analysis of variance ANOVA obtained significant results for both the main effect and interaction effect of differences for the 6 maturity factors across the 11 business units. Regression analysis found a positive association between overall strategic alignment maturity and respondents' self-rated maturity. These exploratory findings show promise for the assessment instrument to be used as a diagnostic tool for organizations to improve their IT-business alignment maturity levels.
Marx's reproduction schemes and the environment

Abstract Ecological economists have argued that Marx's reproduction schemes are self-contained circular flows that downgrade the importance of natural conditions. The present paper evaluates this criticism in light of both Marx's methodology and his response to Quesnay's tableau economique. It is shown that Marx follows Quesnay in clearly distinguishing monetary circular flows from material throughput, and that his schemes encapsulate the dependence of capitalist production on natural conditions as developed elsewhere in Capital. At the same time, the purpose of Marx's schemes is not to theorize environmental crises, but to set out the basic exchanges necessary for capitalist reproduction as a material and social class process. Marx's analyses of capitalist environmental crises are developed at other points in Capital.
The golden section and an algebraic model of ethical cognition

Abstract In experimental investigations related to Kelly's theory of constructs (1955. The psychology of personal constructs. New York: Norton) a special constant was discovered. It was found that subjects on the average choose a positive over a negative pole with the probability 0.62. (Adams-Webber and Benjafield 1973. Canadian Journal of Behavioral Science 5, 234–241). The same constant was also found in other experiments related to the choice of elements marked “good” and “bad.” Benjafield and Adams-Webber (1976. British Journal of Psychology 67, 11–15) hypothesized that the precise value of this constant coincides with “golden section” ≈0.6180. In this paper it is shown that if we suppose that the subjects actualize mechanisms of choice described by the algebraic model of ethical cognition (which was constructed without any relation to the constant 0.62), then the existence of this constant is mathematically explained. Under very broad assumptions its value is 0.625, and under more constrained conditions it is equal to the golden section ratio precisely.