cssi/SciSciGPT-SciSciNet huggingface dataset:
Bond cooperativity and ring formation in hydrogen fluoride thermodynamic properties: A two-density formalism framework

In this work, we develop a thermodynamic perturbation theory using a two-density formalism framework to model the bond cooperativity effect for associating hard sphere and Lennard-Jones fluids. The theory predictions are compared with Monte Carlo simulation results and they are in excellent agreement. We incorporate bond angle dependent ring formation into the theory to calculate hydrogen fluoride thermodynamic properties. The liquid density and vapor pressure obtained by the theory are in good agreement with the experimental data. Comparing the thermo-physical properties of hydrogen fluoride calculated by this theory with previous studies reveals the importance of bond angle dependent ring formation and cooperative hydrogen bonding to capture its anomalous behavior especially in the vapor phase. The cooperativity ratio obtained in our model is close to the values reported by previous quantum studies.In this work, we develop a thermodynamic perturbation theory using a two-density formalism framework to model the bond cooperativity effect for associating hard sphere and Lennard-Jones fluids. The theory predictions are compared with Monte Carlo simulation results and they are in excellent agreement. We incorporate bond angle dependent ring formation into the theory to calculate hydrogen fluoride thermodynamic properties. The liquid density and vapor pressure obtained by the theory are in good agreement with the experimental data. Comparing the thermo-physical properties of hydrogen fluoride calculated by this theory with previous studies reveals the importance of bond angle dependent ring formation and cooperative hydrogen bonding to capture its anomalous behavior especially in the vapor phase. The cooperativity ratio obtained in our model is close to the values reported by previous quantum studies.
Bias-Based Bullying and School Adjustment among Sexual and Gender Minority Adolescents: The Role of Gay-Straight Alliances.

Adolescents identifying as sexual and/or gender minorities face many challenges at school due to stigma-based peer harassment. This study examined the extent to which sexual and gender minority adolescents experience bias-based bullying across a range of stigmatized identities and attributes, as well as the potential of gay-straight alliances (GSAs, also referred to as gender-sexuality alliances) to reduce simultaneously multiple forms of bias-based bullying, and in turn support school adjustment. Using a United States sample of diverse sexual and gender minority adolescents (N = 17,112; Mage = 15.57, SDage = 1.27), multiple mediation analyses indicated lower levels of multiple forms of bias-based bullying (based on body weight, gender, religion, disability, gender typicality, sexuality) at schools with versus without GSAs, and in turn higher perceived school safety, as well as higher grades and reduced school suspension (due to less weight- and sexuality-based bullying). The findings shed light on the broad-reaching stigma-reduction potential of GSAs.
Hidden Impacts of OER: Effects of OER on Instructor Ratings and Course Selection

One solution to the increasing cost of textbooks is open educational resources (OER). While previous studies have evaluated the effects of OER on student performance and perceptions of the material quality, few studies have evaluated other possible effects of OER. The goal of these studies was to examine whether the use of OER changes students’ perceptions of instructors whether students are more likely to select hypothetical courses using OER than courses using commercial materials. Results indicated that instructors assigned to use OER were rated more positively than those assigned a commercial textbook and students were more likely to select courses that had no course costs. These findings should motivate instructors and universities to adopt and advertise their OER use.
P88 SNAP4CT.org: An Online Nutrition Education Platform for CT SNAP Recipients

Objectives To provide SNAP with: mobile-friendly education to assist with obtaining and preparing healthy, budget-friendly foods; information on free health events; and access to RDs to answer their nutrition questions. Use of Theory or Research Low-income residents use cell phones for internet access. The SNAP4CT.org mobile-friendly, web-based platform for participants to access nutrition resources. Best-practices for e-marketing support Search Engine Optimization (SEO), marketing, and paid ads/boosts as strategies for reaching target populations. We utilize these strategies to reach SNAP eligibles in CT municipalities with the most SNAP participants. Target Audience SNAP4CT.org targets SNAP eligible 18- to 59-year-olds. Program Description SNAP4CT.org is a mobile-friendly resource including a website and associated social media providing CT SNAP eligibles with information on accessing and preparing healthy, budget-friendly foods. This platform serves as a point of collaboration for CT SNAP-Ed contractors, and as a vehicle to share resources with community partners who serve SNAP eligibles. We use SEO and promote content on social media using paid ads and boosting to reach and engage persons eligible for SNAP-Ed. Evaluation Methods Process evaluation uses Google Analytics, social media metrics, and administrative data to examine usage and growth over time. We track pageviews, form submissions, newsletter opens, video views, direct likes, and follows. In addition, we conducted surveys in FY 2018 and FY 2019 to ensure that SNAP4CT.org reaches our target population. Results Process evaluation data shows substantial growth in utilization. In 2019, visitors from 161 of CT's 169 cities/towns engaged with the platform, accounting for 683,276 online interactions. Surveys validate the approach taken to reach our audience - see: https://www.snap4ct.org/toolkit.html Conclusions Process evaluation data shows a nearly 20-fold increase in usage of SNAP4CT.org from 2015 to 2019. Survey results suggest that the use of the website and social media is a relevant strategy to reach our target population. Funding Supplemental Nutrition Assistance Program - Education.
Emap2sec+: Detecting Protein and DNA/RNA Structures in Cryo-EM Maps of Intermediate Resolution Using Deep Learning

Abstract An increasing number of density maps of macromolecular structures, including proteins and protein and DNA/RNA complexes, have been determined by cryo-electron microscopy (cryo-EM). Although lately maps at a near-atomic resolution are routinely reported, there are still substantial fractions of maps determined at intermediate or low resolutions, where extracting structure information is not trivial. Here, we report a new computational method, Emap2sec+, which identifies DNA or RNA as well as the secondary structures of proteins in cryo-EM maps of 5 to 10 A resolution. Emap2sec+ employs the deep Residual convolutional neural network. Emap2sec+ assigns structural labels with associated probabilities at each voxel in a cryo-EM map, which will help structure modeling in an EM map. Emap2sec+ showed stable and high assignment accuracy for nucleotides in low resolution maps and improved performance for protein secondary structure assignments than its earlier version when tested on simulated and experimental maps.
Transforming educator identities and roles in family engagement through critical participatory action research

Transformative approaches are essential for teachers, researchers, and teacher educators to rethink their identities and roles and to position themselves as both collaborators with and learners fro...
Linguistic markers predict onset of Alzheimer's disease.

Abstract Background The aim of this study is to use classification methods to predict future onset of Alzheimer's disease in cognitively normal subjects through automated linguistic analysis. Methods To study linguistic performance as an early biomarker of AD, we performed predictive modeling of future diagnosis of AD from a cognitively normal baseline of Framingham Heart Study participants. The linguistic variables were derived from written responses to the cookie-theft picture-description task. We compared the predictive performance of linguistic variables with clinical and neuropsychological variables. The study included 703 samples from 270 participants out of which a dataset consisting of a single sample from 80 participants was held out for testing. Half of the participants in the test set developed AD symptoms before 85 years old, while the other half did not. All samples in the test set were collected during the cognitively normal period (before MCI). The mean time to diagnosis of mild AD was 7.59 years. Findings Significant predictive power was obtained, with AUC of 0.74 and accuracy of 0.70 when using linguistic variables. The linguistic variables most relevant for predicting onset of AD have been identified in the literature as associated with cognitive decline in dementia. Interpretation The results suggest that language performance in naturalistic probes expose subtle early signs of progression to AD in advance of clinical diagnosis of impairment. Funding Pfizer, Inc. provided funding to obtain data from the Framingham Heart Study Consortium, and to support the involvement of IBM Research in the initial phase of the study. The data used in this study was supported by Framingham Heart Study's National Heart, Lung, and Blood Institute contract (N01-HC-25195), and by grants from the National Institute on Aging grants (R01-AG016495, R01-AG008122) and the National Institute of Neurological Disorders and Stroke (R01-NS017950).
Predictors of Contraceptive Self-Efficacy and Condom Use Among Young Black Women Who Have Sex With Women and Men

Black women who have sex with women and men (BWSWM) are at risk for unplanned pregnancies, human immunodeficiency virus (HIV), and other sexually transmitted infections (STIs). However, there is a ...
Motion parallax thresholds for unambiguous depth perception.

Abstract The perception of unambiguous depth from motion parallax arises from the neural integration of retinal image motion and extra-retinal eye movement signals. It is only recently that these parameters have been articulated in the form of the motion/pursuit ratio. In the current study, we explored the lower limits of the parameter space in which observers could accurately perform near/far relative depth-sign discriminations for a translating random-dot stimulus. Stationary observers pursued a translating random dot stimulus containing relative image motion. Their task was to indicate the location of the peak in an approximate square-wave stimulus. We measured thresholds for depth from motion parallax, quantified as motion/pursuit ratios, as well as lower motion thresholds and pursuit accuracy. Depth thresholds were relatively stable at pursuit velocities 5–20 deg/s, and increased at lower and higher velocities. The pattern of results indicates that minimum motion/pursuit ratios are limited by motion and pursuit signals, both independently and in combination with each other. At low and high pursuit velocities, depth thresholds were limited by inaccurate pursuit signals. At moderate pursuit velocities, depth thresholds were limited by motion signals.
Postural differences between asymptomatic men and women and craniofacial pain patients

A forward head position and rounded shoulders have been implicated in the development or perpetuation of craniomandibular disorders. Since women seek treatment for these problems more frequently than men, postural differences may account for the increased incidence of symptoms in women. The purposes of this study were (1) to compare the sagittal head and shoulder posture of asymptomatic men and women and (2) to compare the posture of asymptomatic and symptomatic women to determine differences in sagittal plane posture. Subjects were 20 asymptomatic men and women volunteers and nine consecutive women patients presenting for evaluation and treatment of craniomandibular pain. The subjects were compared using a valid, reliable, computer-assisted slide digitizing system called the Postural Analysis Digitizing System (PADS). Asymptomatic men and women did not differ in the postural characteristics associated with craniomandibular disorders. Sagittal posture does not appear to be a gender-related factor in these disorders. Symptomatic women, however, do display these postural characteristics to a greater extent than asymptomatic women. Evaluation and treatment of postural dysfunction should be included in the management of these patients.
Free Quality PDA Software for Physicians

As PDAs are becoming practical tools for health care professionals, medical librarians are frequently asked to give recommendations of PDA software. Based on recommendations from medical librarians, physicians, and medical students, an annotated list of free PDA software has been compiled to meet the needs of medical librarians. The list includes software for Palm OS and Pocket PC and is divided into sections based on the software's function.
Aggressive and violent behaviors in the school environment among a nationally representative sample of adolescent youth.

BACKGROUND: The purpose of this study was to describe the prevalence of aggressive and violent behaviors in the context of the school environment in a nationally representative sample of adolescent youth and to illustrate these patterns during 2001-2011. METHODS: We analyzed data from 84,734 participants via the Youth Risk Behavior Surveillance System (YRBSS). Frequencies were visualized using heatmaps. One-way analyses of variance and corresponding post hoc tests helped to identify if differences in prevalence fluctuated significantly across all years. RESULTS: Rates of youth feeling unsafe in their school environment, bringing weapons to school, and engaging in physical fighting on school property continue to persist. FINDINGS illustrated that Hispanic youth and youth classified as "other" have emerged as particularly high-risk demographic subgroups over the past decade. Peer victimization and sexual victimization continue to affect girls disproportionately. CONCLUSIONS: Though some variation within demographic subgroups exists, rates of aggressive and violent behaviors in the context of the school environment continue to persist. Implications for the coordinated prevention of aggressive and violent behaviors among adolescent youth are discussed and recommendations for school-based prevention efforts are identified. Language: en
Tax Policy and Business Investment

Abstract In this survey, we review research on tax policy and business investment with four objectives. First, we use a simple prototypical dynamic neoclassical investment model to derive and explain effects of taxation on business investment in the long run and short run. Second, we describe and evaluate empirical tests of neoclassical channels, and we conclude that recent empirical evidence is consistent with neoclassical intuition. Third, we explore qualifications to basic theoretical models and their empirical tests raised by recent research on irreversibility and capital-market imperfections. Finally, we evaluate arguments for and against using tax policy to influence the level or timing of investment. While there is a consensus about the nature and magnitude of tax policy on investment demand considerable uncertainty remains regarding the structure of adjustment costs and the short-run dynamic effects of tax reforms. Consistent with our analysis of equilibrium investment outcomes, ascertaining the effects of tax policy on equilibrium investment requires additional research to examine responsiveness of interest rates, output, and the stock market to tax policy changes.
Thin-Layer Chromatography

Thin-layer chromatography , Thin-layer chromatography , کتابخانه مرکزی دانشگاه علوم پزشکی تهران
A Geopolitical Analysis of the Configuration of Israel's Security Barrier with Palestine

This paper applies traditional methods of geopolitical analysis to the characteristics and consequences of the Israeli security barrier currently being constructed along Israel's border with the Palestinian West Bank. Special attention will focus on the semantics of the barrier, the history of the barrier's construction, and the political, economic and humanitarian effects the barrier has on the viability of a prospective Palestinian state.
Finite-difference solution of Poisson's equation in rectangles of arbitrary proportions

The recently devised sixth order method for solving difference analogues of Poisson's equation affords much economy of computing effort if squares can be used for the grid elements. However, some developments result in rectangles with one side an irrational multiple of the other, for which the grid elements cannot be squares. A method is presented for handling this situation.
Acquisition of conditioned suppression and responsivity to thermal stimulation in spontaneously hypertensive, renal hypertensive and normotensive rats

Abstract The acquisition of conditioned suppression of instrumental responding and responsivity to thermal stimulation were assessed in spontaneously hypertensive rats of the Okamoto-Aoki strain (SHRs), renal hypertensive rats of the Wistar-Kyoto strain (WKYs), and normotensive WKY rats. Spontaneously hypertensive rats showed significantly faster acquisition of conditioned suppression than age-matched WKY normotensive rats. This acquisition difference between SHRs and normotensive WKYs was maintained even following chronic preexposure to shock alone; a treatment that retarded normal acquisition of conditioned suppression. In contrast, renal hypertensive WKYs acquired conditioned suppression at the same rate as age-matched normotensive WKYs. Spontaneously hypertensive rats and renal hypertensive WKYs both showed significantly longer latencies than normotensive WKYs to respond to thermal stimulation using a hot-plate assay. These outcomes suggest that the relationship between blood pressure and the acquisition of conditioned suppression in SHRs is either pleiotrophic or a consequence of random fixation, and that acquisition of conditioned suppression may serve as a valuable marker variable of hypertension in the SHR. The dissociation between acquisition of conditioned suppression and responsivity to thermal stimulation suggests that different mechanisms may mediate nociceptive responses to shock and thermal stimulation in these models of hypertension.
Nonclassical respiratory activity of tissue slices.

Abstract The relationship between respiration rate and ambient oxygen tension has been measured for fresh liver, kidney, heart, and brain slices. Statistical procedures are developed for discriminating between the kinetics predicted by the classical diffusion model and those of the Michaelis-Menten equation suggested in earlier papers. In all tissue slices the Michaelis-Menten equation tended to fit better than the classical model. The differences in fit were most pronounced in liver slices and smallest for kidney and brain slices. The classical model is clearly unsatisfactory for liver and heart tissue. Several explanations are discussed including the hypothesis that a significant part of the oxygen transport is by carrier. The possible nature of such a carrier is considered.
Novel radiation hardened latch design considering process, voltage and temperature variations for nanoscale CMOS technology

Abstract As CMOS technology is scaled down, the supply voltage and gate capacitance are reduced, which results in the reduction of charge storing capacity at each node and increase of the susceptibility to external noise in radiation environments. The traditional error tolerant circuit design methods provide very limited protection against the environment noise for storage cells such as latches and memories. In this paper, a novel hardened latch design is proposed and compared with the previous hardened latch designs using 32 nm technology node. Extensive simulation results using HSPICE are reported to show that the proposed hardened latch design achieves 15× improvement of critical charge (Qcrit) with comparable cost in terms of speed and power compared to the most up to date hardened latch design. Moreover, PVT variations have great impact on the reliability of hardened circuit. The proposed latch circuit is also evaluated with the presence of PVT variations and demonstrates higher robustness than other considered robust latch under severe PVT variation condition.
The impact of atmospheric aerosols on trace metal chemistry in open ocean surface seawater, 1. Aluminum

Abstract Significant quantities of aerosol aluminum are transported from continental regions through the atmosphere to the oceans. Enrichments in the concentration of dissolved aluminum in open ocean surface seawater suggest that dissolution of aerosol aluminum is an important source of dissolved aluminum to these waters. Atmospheric aerosols collected at Enewetak Atoll were exposed to seawater and artificial rain water to determine directly the importance of atmospheric deposition as a source of marine dissolved aluminum. The results of these experiments indicate that ∼ 8–10% of the aluminum in atmospheric aerosols of crustal origin over the North Pacific is soluble in seawater. Approximately 5–6% dissolves very rapidly ( Nearly the same amount of aerosol aluminum dissolved in artificial rain water (pH= 5.5) in 6 hr as dissolved in seawater (pH= 8) in 60 hr. The lower pH appears to not only increase the dissolution rate but may also increase the quantity of aerosol aluminum that dissolves. Dissolved organic matter in seawater appears to have relatively little effect on aerosol aluminum dissolution. Considering measured total aerosol aluminum fluxes, aluminum dissolution of 5–10% would constitute the major source for dissolved aluminum in surface waters of the open North Pacific. The calculated residence time of dissolved aluminum in the upper 100 m of the tropical North Pacific ranges from 2 to 6 years.
Light-scattering fingerprinting for characterization of smooth-muscle cell proliferation

Accelerated proliferation of smooth muscle cells (SMC) is known to play an integral role in atherosclerotic lesion formation. Thus, there has been significant interest in defining both positive and negative regulators of SMC growth. We have applied a novel optical technique referred to as four-dimensional light scattering fingerprinting (4D-ELF) that enables non-invasive assessment of living cells. 4D-ELF can serve for highly sensitive detection of slight alterations in cellular and subcellular microstructure. Using 4D-ELF, we characterized the proliferation of SMC grown on two different substrates: laminin and fibronectin. Fibronectin-grown SMC have been previously shown to be more proliferative. Our results indicate that light scattering can be used to monitor the changes in the intracellular structure caused by the cell-substrate interaction and differentiate between more and less proliferative SMCs. Thus, light scattering fingerprinting may potentially provide a quick, inexpensive, and accurate means to noninvasively characterize the proliferation of living cells as well as cell-biomaterial interaction.
Relative efficacy of various strategies for visual feedback in standing balance activities

Seventy-nine young, healthy adults were led through static balance and weight-shifting activities in order to study the effects of visual feedback on balance. Based on their performance, the relative effects of various feedback properties were analyzed: (1) arrangement [direct center of pressure (CoP) vs. lateral weight distribution feedback], (2) numbers (presence vs. absence of numeric feedback), and (3) dimensionality (1D vs. 2D CoP information). In the static balance activity, subjects were instructed to maintain equal weight across both feet; in the dynamic weight-shifting activity, subjects were instructed to shift their weight to each displayed target location. For static balance, lateral symmetry and sway were measured by classical parameters using CoP, center of gravity (CoG), and the difference between the two (CoP–CoG). Weight-shifting balance performance was measured using the time required to shift between target CoP positions. Results indicated that feedback arrangement had a significant effect on static sway and dynamic weight shifting, with direct CoP feedback resulting in better balance performance than lateral weight distribution. Also, numbers had a significant effect on static sway, reducing lateral sway compared to feedback without numbers. Finally, 2D CoP feedback resulted in faster performance than 1D CoP feedback in dynamic weight shifting. These results show that altering different properties of visual feedback can have significant effects on resulting balance performance; therefore, proper selection of visual feedback strategy needs to take these effects into consideration.
Effect of Stress-Induced Degradation in LDMOS $\hbox{1}/f$ Noise Characteristics

Low-frequency noise in double reduced-surface-field lateral-double-diffused-MOS devices has been measured, and the effect of dc stressing is analyzed. The noise components contributing from the extended drain regions under the gate and field oxides were differentiated from the channel noise by a series of experimental and analytical techniques. The effect of voltage stressing on each noise component was investigated. Trapped-charge carrier fluctuations due to Si/SiO2 interface traps in the overlap region in the extended drain as well as in the channel were found to be the dominant source of noise. The bulk resistance fluctuations in the extended drain region under the field oxide were found to be insignificant. High-voltage stressing caused an increase in the interface traps, thus increasing both the extended drain overlap resistance and the noise.
Recovery from mu-opioid receptor desensitization after chronic treatment with morphine and methadone

Chronic treatment with morphine results in a decrease in μ-opioid receptor sensitivity, an increase in acute desensitization, and a reduction in the recovery from acute desensitization in locus ceruleus neurons. With acute administration, morphine is unlike many other opioid agonists in that it does not mediate robust acute desensitization or induce receptor trafficking. This study compares μ-opioid receptor desensitization and trafficking in brain slices taken from rats treated for 6-7 d with a range of doses of morphine (60, 30, and 15 mg · kg(-1) · d(-1)) and methadone (60, 30, and 5 mg · kg(-1) · d(-1)) applied by subcutaneous implantation of osmotic minipumps. Mice were treated with 45 mg · kg(-1) · d(-1). In morphine-treated animals, recovery from acute [Met](5)enkephalin-induced desensitization and receptor recycling was diminished. In contrast, recovery and recycling were unchanged in slices from methadone-treated animals. Remarkably the reduced recovery from desensitization and receptor recycling found in slices from morphine-treated animals were not observed in animals lacking β-arrestin-2. Furthermore, pharmacological inhibition of G-protein receptor kinase 2 (GRK2), although not affecting the ability of [Met](5)enkephalin to induce desensitization, acutely reversed the delay in recovery from desensitization produced by chronic morphine treatment. These results characterize a previously unidentified function of the GRK/arrestin system in mediating opioid regulation in response to chronic morphine administration. They also suggest that the GRK/arrestin system, rather than serving as a primary mediator of acute desensitization, controls recovery from desensitization by regulating receptor reinsertion to the plasma membrane after chronic treatment with morphine. The sustained GRK/arrestin-dependent desensitization is another way in which morphine and methadone are distinguished.
Are there interactive protocols for CO-NP languages?

Etude du probleme consistant a determiner quels types de langage peuvent traiter des protocoles interactifs
Social security, public education and the growth–inequality relationship

Abstract We study how the relationship between economic growth and inequality depends upon the levels of funding of two of the largest government programs, public education and social security. We do this in the context of an overlapping generations economy with heterogeneous agents where the government collects a tax on labor income to finance these programs. We show that in our model an increase in government spending on social security reduces income inequality and can have a non-monotonic effect on growth. When the initial level of social security funding is low, as is the case in most poor economies, then its increase will enhance growth. When its funding level is high as is typical for developed countries, we show that its further increase can slow down growth while reducing income inequality. These results obtain regardless of whether the increase in social security funding is financed by a tax increase or by cutting the public education budget. We also find that the effects of increasing the level of public education expenditures or the overall size of the government budget (holding the budget composition fixed) are characterized by similar non-monotonic growth–inequality relationships.
Carcinogen Exposure and Epigenetic Silencing in Bladder Cancer

Tobacco smoking, certain occupational exposures, and exposure to inorganic arsenic in drinking water have been associated with the occurrence of bladder cancer. However, in these tumors the exposure-associated pattern of somatic alterations in genes in the causal pathway for disease has been poorly characterized. Animal and in vitro studies have suggested that arsenic, tobacco carcinogens, and other exposures may act through epigenetic mechanisms. We, therefore, examined, in a population-based study of human bladder cancer (n = 351), the relationship between epigenetic silencing of the tumor-suppressor genes, p16(INK4A), RASSF1A, PRSS3, and the four SFRP genes and exposure to both tobacco and arsenic in bladder cancer. Promotor methylation silencing of each of these genes occurred in approximately 30-50% of bladder cancers. Epigenetic silencing of RASSF1A and PRSS3 and any of the SFRP genes were each significantly associated with advanced tumor stage (P < 0.001, P < 0.04, and P < 0.005, respectively). Arsenic exposure, measured as toenail arsenic, was associated with RASSF1A (P < 0.02) and PRSS3 (P < 0.1) but not p16(INK4A) or SFRP promotor methylation, in models adjusted for stage and other risk factors. Cigarette smoking was associated with a greater than twofold increased risk of promotor methylation of the p16(INK4A) gene, with greater risk seen in patients with exposures more recent to disease diagnosis, and smoking was also significantly associated with any SFRP gene methylation (P < 0.01). These results from human bladder tumors, add to the body of animal and in vitro evidence that suggests bladder carcinogens play a crucial role in the induction of important epigenetic alterations.
Coherence Theory And Caustic Corrections

Recent studies in underwater acoustics have shown how coherence theory may be used to determine the correct intensity distribution in the neighborhood of caustics. These studies may be of interest to the optics community and we review here the method developed. We begin with the basic equation governing the coherence function in the parabolic approximation. The radiation propagates in a medium with a variable mean index of refraction. A lowest order approximation to the basic equation yields the geometric optics solution. To next order we use a two-scale expansion to include the correction term to the geometric optics calculation. This gives the correct intensity distribution in the neighborhood of caustics and it is shown that in the limit of a point source the results reduce to those obtained previously. The results of a numerical example are given. Finally it is pointed out that if there is volume scattering, resulting from a stochastic variation in the index of refraction field, the method may be extended to determine the intensity corrections near a caustic due to this effect.© (1982) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
937 INTERACTION OF PYRUVATE/LACTATE AND NAD/NADH RATIOS IN THE REGULATION OF RED CELL (RBC) GLYCOLYSIS

In vivo, the final products of RBC glycolysis, pyruvate (PA) and lactate (LA), diffuse into the plasma, and a steady level of glycolytic intermediates is maintained within the cell. In vitro, when RBCs are incubated with glucose (GL) in a closed system, an increase in fructose-1, 6-diphosphate (FDP) and triose phosphates (TP) rapidly takes place, rising twenty-fold in 3 hours. This makes in vitro studies of glycolytic intermediates impossible. We have incubated RBCs in an open system that allows physiologic diffusion of the PA and LA produced. In this system, in the presence of GL alone, the accumulation of FDP and TP is markedly reduced, with a six-fold increase over normal. On addition of PA only, the accumulation of FDP and TP is suppressed, and steady state concentrations are observed. On addition of LA only, however, the accumulation of FDP and TP is again twenty-fold as in the closed system. On addition of both PA and LA, at the physiological ratio of 1/19, regardless of concentration, the accumulation of FDP and TP is suppressed, with levels similar to those observed with PA only. If LA is increased and the PA/LA ratio is significantly reduced, then accumulation of FDP and TP occurs. When LA increases in the RBCs, an accumulation of NADH takes place at the LDH step, and thus glycolysis is slowed at the level of the 3-phosphoglyceraldehyde dehydrogenase (3-PGAD) step, through NADH inhibition. An excess of pyruvate lowers the NADH concentration at the LDH step, in turn releasing the inhibition of 3-PGAD. These data suggest that the orderly flow of glycolysis in RBCs depends on the diffusion of the PA and LA produced, to maintain a constant intracellular PA/LA ratio, necessary to regulate the intracellular NAD/NADH ratio. An open system of incubation approximates closely physiologic conditions and its use allows control of glycolysis in vitro, with this technique it is possible to study in vitro glycolytic intermediate levels, in normal and abnormal conditions.
Intraocular lens implants and risk of endophthalmitis.

Editor,—We would like to comment on the paper by Bainbridge et al .1 The aim of their study was to investigate the possible association between the use of three piece foldable silicone polypropylene intraocular lenses and increased risk of endophthalmitis, and indeed the investigators have …
Effects of two Danish flyashes on alkali contents of pore solutions of cement-flyash pastes

Abstract The influence of two Danish flyashes on alkali contents and other characteristics of cement paste pore solutions was investigated by preparing pastes with 30 percent replacement of cement with flyash, hydrating for up to six months, and expressing and analyzing the resulting pore solutions. Reference cement pastes (without flyash) were found to retain about 80 percent of the total potassium and about 60 percent of the total sodium of the cement in solution indefinitely, leading to solution concentrations of about 0.6M in combined alkalies. The alkali contents of the flyashes used were substantial (2.4 and 3.3 percent Na2O equivalent), and some of this is “available” as measured by standard tests. Despite this, neither flyash was found to contribute to the alkali content of the pore solutions. One was essentially inert to alkalies, the other extracted a small proportion of alkalies from the pore solutions.
Ligninolytic system of Phanerochaete chrysosporium: Inhibition by o-Phthalate

The degradation rate of [synthetic-14C]-lignin to 14CO2 by Phanerochaete chrysosporium in cultures buffered with 0.01 M 2,2-dimethylsuccinate (DMS) was twice that in 0.01 M o-phthalate-buffered cultures. This difference could be totally accounted for by o-phthalate inhibition of the activity of the ligninolytic system. 14CO2 production from ring-, sidechain-, and methoxyl-labeled lignins was inhibited, the degree of inhibition being dependent on o-phthalate concentration. Oxidations of 14C-glucose, 14C-acetovanillone, and 14C-apocynol were not inhibited; thus o-phthalate is not a general inhibitor, and might inhibit activities involved in attack of the lignin polymer. DMS is a suitable buffer for the ligninolytic system. Degradation rates of ring-labeled lignin to 14CO2 of 10–15% in 24 h were obtained consistently over the pH range 3.6–4.5, with an optimum near pH 4.0.
A Penrose polynomial for embedded graphs

We extend the Penrose polynomial, originally defined only for plane graphs, to graphs embedded in arbitrary surfaces. Considering this Penrose polynomial of embedded graphs leads to new identities and relations for the Penrose polynomial which cannot be realized within the class of plane graphs. In particular, by exploiting connections with the transition polynomial and the ribbon group action, we find a deletion-contraction-type relation for the Penrose polynomial. We relate the Penrose polynomial of an orientable chequerboard colourable graph to the circuit partition polynomial of its medial graph and use this to find new combinatorial interpretations of the Penrose polynomial. We also show that the Penrose polynomial of a plane graph G can be expressed as a sum of chromatic polynomials of twisted duals of G. This allows us to obtain a new reformulation of the Four Colour Theorem.
Six language extensions to enhance the portability of mathematical software written in PL/I: background and justification

As part of its revision of ANS PL/I, American National Standards Committee X3J1 is considering extensions like those described here to aid in the development of high-quality portable mathematical software.The new features include environmental enquiry functions, generalization of "restricted expressions" (compile-time expressions), liberalization of the contexts of restricted expressions, a named-literal declaration type, explicit, precision specification for constants, and a pragmatic statement for expressing conditions that an implementation must satisfy for acceptable compilation. Used together, these features will give numerical analysts access to properties of an implementation's floating-point arithmetic in exactly the ways required to ease the burden of tailoring a program's precision specifications to new environments. In many cases it will be possible to write PL/I programs that are completely self-adapting to their host environment.Effective definition of the environmental enquiry functions will require the incorporation of an explicitly parameterized model of floating-point arithmetic; the environmental enquiry functions and the results of arithmetic operations will then be consistently defined in terms of the same parameters. If an appropriate model (to be described in a future paper) is adopted by the Committee and properly integrated into the Standard, a significant advantage will be offered to numerical analysts: they will be able to state and prove theorems about their programs' error bounds by appealing directly to the Standard.In addition to describing the proposed extensions, this paper presents a careful justification and a detailed example of their intended use.None of these features has yet been adopted by X3J1. The Committee is interested in the reactions of the mathematical software community to these ideas and requests that comments be sent to the author.
Accessory glands and their ducts in the reproductive system of the male toadfish, Opsanus tau

The accessory genital glands ofOpsanus tau are large fan-shaped organs lying in the posterior region of the abdominal cavity. Four distinct parts on each side can be recognized grossly and microscopically by virtue of morphology, color, secretion granules, and vascularity. All four parts have separate collecting ducts which drain into the paired spermatic ducts as they course posteriorly to exit into the cloaca via a grooved genital papilla. Seasonal changes in the gross and microscopic anatomy of the accessory glands are described.
Experimental Study of Frost Formation on a Flat Surface Under Nature Convection

A series of experiments were conducted to investigate the frost formation and characteristics on a flat surface under natural convections. The process of frost formation and structures is visibly observed and measured by using of a microscope. The temperature distribution of the air around the frost layer is measured by using of the holographic interferometry technique. The influences of the main parameters are analyzed. Especially, the microscopic analysis of frost growth on the surface characteristics on the microscopic characteristics of a frost layer during the early growth period when sub-cooled droplets are formed and changed to the ice. The thickness and mass of frost layer are measured while frost formation is visualized simultaneously. The results show that the frost surface temperatures are much lower than the freezing temperature and close to the cold surface temperature at the early growth period. After the early growth period, the frost surface temperature is dominated by the convective heat transfer between the frost surface and surrounding air.Copyright © 2003 by ASME
A Nuclear Detector Gain Stabilizing Technique with Only One Stable Gain Position

A nuclear radiation detector gain stabilizing scheme has been developed which offers the unique advantage of having only one stable operating gain position by utilizing a gated radioactive source and broad digital windows. This scheme can be used on space missions or other remote locations where turn-on adjustments would be difficult or impossible, as well as on large detector arrays where such adjustments would be very time consuming. The technqiue has been incorporated into the Gamma Ray Spectrometer on NASA's Solar Maximum Mission, where an overall pulse height resolution of ~ 7% at 0.662 MeV, with a seven-detector array of 7.6 cm × 7.6 cm NaI scintillators, is realized. This work was supported by NASA under Grant NGL 30-002-021 and contract NAS 5-23761.
Quality of Reduced-Fat Frankfurter Modified by Konjac–Starch Mixed Gels

Konjac–potato starch mixed gels were incorporated into reduced-fat (18%) frankfurters and compared with reduced-fat (18% fat, C18) and high-fat (28% fat, C28) controls for textural, sensory properties, and storage stability. At the same konjac concentration, increasing starch level resulted in lower G′ (storage modulus) and G″ (loss modulus) of the konjac–potato starch mixtures leading to more elastic-mixed gels. No differences in textural hardness among gel-added treatments were noticed. C28 had the lowest sensory firmness and highest juiciness scores. C18 and gel-added treatments had similar juiciness and firmness scores, and all treatments did not differ in overall acceptability.
Visualizing generalized 3x+1 function dynamics

Abstract The function that results in 3x+1 for odd integers x and half of x for even x has led to intriguing questions. The 3x+1 conjecture states that iteration of that function on positive integers eventually results in the value 1. We investigate many generalizations of that function to the complex domain and visualize the resulting dynamics using escape time, stopping time, and basin of attraction images. We will see beautiful, rich dynamics consistent with the conjecture. We see that some generalizations have relatively simple real dynamics, which may make them useful for analysis and we see a complex generalization where sequences of stable egg shaped regions appear in coefficient stopping time images that suggest remarkable patterns for such stopping time.
Neuroblastoma Cells Transiently Transfected to Simultaneously Express the Co-Stimulatory Molecules CD54, CD80, CD86, and CD137L Generate Antitumor Immunity in Mice

The goal of this study was to show that nonviral gene transfection technology can be used to genetically modify neuroblastoma cells with immune stimulatory molecules, and that the modified cells can generate an antitumor immune response. The authors found that an electroporation-based gene transfection method, nucleofection, could be used to modify mouse AGN2a (an aggressive variant of Neuro-2a) neuroblastoma cells to simultaneously express as many as four different immune stimulatory molecules encoded by separate plasmid vectors. Within 18 hours after nucleofection, greater than 60% of the cells typically expressed the transfected gene products, and the percentages of cells expressing the products often exceeded 96%. High levels of plasmid in cell nuclei immediately after nucleofection documented instantaneous availability of gene vectors to the transcriptional machinery. AGN2a cells nucleofected to express the co-stimulatory molecules CD80 and CD86 expressed higher levels of these molecules than cells that had been permanently transfected with these same plasmid vectors, and the nucleofected cells were as effective as the permanently transfected cells at inducing an antitumor response in vivo in a tumor prevention model. AGN2a cells nucleofected with four separate plasmid vectors encoding CD54, CD80, CD86, and CD137L induced a T-cell immune response in vitro and served as a potent tumor vaccine in the tumor prevention model. These data show that transient transfection using a nonviral based method, nucleofection, can be used to rapidly generate novel cell-based tumor vaccines.
ESTABLISHING OPTIMAL MAINTENANCE PRACTICES IN A TRADITIONAL MANUFACTURING ENVIRONMENT

All machinery and equipment in a manufacturing environment are subject to routine preventive inspection and maintenance procedures that disable the item for a short time. The purpose of these periodic procedures is to perform necessary routine maintenance to ensure that more catastrophic, long-term breakdowns are avoided. These routine procedures are typically performed based on a predetermined schedule that has been derived by hindsight and anecdotal evidence. This paper presents a methodology for maintenance decision-making. It provides the framework and decision-support system for determining the proper maintenance paradigm to be used on any machine, from a reactive system that repairs equipment only when they break, to a preventive maintenance system based on a static schedule, to an intelligent predictive system.
Review of Well Logging in the Basin and Range Known Geothermal Resource Area

A discussion is presented of applications and interpretations of well logs to Basin and Range Province geothermal exploration and development. Problems experienced in use of conventional oilfield tools and techniques are reviewed, and methods to circumvent these problems are illustrated. Particular examples focus on log responses and matrix effects in complex lithologies. 36 refs.