cssi/SciSciGPT-SciSciNet huggingface dataset:
Electrical responses of frog spinal ganglion cells in sodium-free media.

SINCE Lorente de No1 found that a group of small axons (“Et fibres”) in the frog are able to conduct prolonged action potentials when the external sodium is replaced by certain quaternary ammonium ions, special attention has been directed to the effects of these compounds on other excitable tissues. Fatt and Katz2 observed that the electrical responses of crustacean muscle fibres are maintained and even intensified when choline, tetramethylammonium, tetraethylammonium or tetrabutylammonium ions are substituted for the sodium in the external medium. No other excitable tissue, however, has been reported to show active responses after complete replacement of sodium by these ions. Choline, in particular, has repeatedly been used as an ‘inert’ osmotic substitute in experiments on sodium depletion in the extracellular spaces. At low concentrations, for example, 10–20 per cent replacement of sodium, tetraefchylammonium lengthens the falling phase of the action potential of crustacean nerve3 and of frog twitch muscle4. The intracellular injection of tetraethylammonium into the giant axon of the squid prolongs the duration of the action potential5. In frog nerve fibres, the enhancement of the negative after-potential produced by addition of tetraethylammonium to the Ringer's solution is more prominent in the terminal endings than in the nodes6, suggesting that quaternary ammonium ions might act in different degrees on the various parts of the neurone.
Hypervelocity impact of bumper-protected fuel tanks.

Fracture of bumper protected fuel tanks subjected to hypervelocity meteoroid impact, applying method of characteristics to stress wave propagation in tank walls
Genetic complexity and serum reactivity of HVR1 quasispecies of hepatitis C virus in patients with cirrhosis

Abstract OBJECTIVE: The RNA genome of hepatitis C virus varies considerably, especially within the hypervariable region 1 (HVR1), a domain located on the 5′ end of the E2/NS1 envelope region. Our previous study has suggested there were greater numbers of quasispecies in the liver than in matched serum, independent of the viral load. However, the significance of this finding has not been examined extensively at genetic and serological levels. METHODS: By large scale cloning and sequencing, we studied the genetic complexity of HVR1 quasispecies in two selected patients with cirrhosis. The serum reactivity of peptides representing different HVR1 quasispecies isolated from these cases was also estimated by standard ELISA format. RESULTS: We found the same major (dominant and/or subdominant) viral quasispecies variants in serum and in the cirrhotic liver. Genetic analysis suggested that the evolutionary pressure on HVR1 was higher than on its flanking region in quasispecies derived from the liver, whereas this trend is attenuated in quasispecies from serum. The immunoreactivity to peptides representing different HVR1 quasispecies variants showed considerable cross-reactivity with heterologous sera, whereas the reactivity was strongest against the dominant HVR1 peptide over time in homologous sera. CONCLUSIONS: These findings indicate that the formation and selection of HVR1 quasispecies may not be driven solely by humoral immune pressure, at least in these two cases.
Magnetic resonance evaluation of the knee in children and adolescents with achondroplasia

Achondroplasia is the most common form of skeletal dysplasia. Although the radiographic features are well described, MRI features of the knee in achondroplasia have not been reported. To describe common MRI characteristics of the knee joint in symptomatic children and adolescents with achondroplasia. We retrospectively evaluated 10 knee MRI examinations in 8 children and young adults (age range 11–20 years, mean 16.3 years) with achondroplasia. We measured modified Insall-Salvati index, knee flexion angle, anterior cruciate ligament (ACL)–Blumensaat line angle, ACL–tibial angle, posterior cruciate ligament (PCL) angle, intercondylar notch width index, and intercondylar notch depth index. We compared our findings with an age- and gender-matched control group of 20 children (age range 15–18 years; mean 16 years) with normal knee MRIs. All 10 knees in the achondroplasia group had discoid lateral meniscus; 8 meniscal tears were identified. Patella baja was present in half of the study cases. Greater knee flexion and increased ACL–Blumensaat line and PCL angles were seen in all achondroplasia knees. ACL–tibial angle was similar in the study and in the control group. Children with achondroplasia had deeper A-shape femoral notches that extended more anteriorly than those seen in the control group. MRI findings were confirmed in all seven knees with arthroscopic correlation. Discoid lateral meniscus, often with tear, is a consistent feature in knee MRIs of symptomatic children and adolescents with achondroplasia. Other findings include patella baja, knee flexion, deep A-shape intercondylar notch, increased ACL–Blumensaat line angle and taut PCL.
Echocardiography in Coronary Artery Disease

CHOCARDIOGRAPHY was introduced as a viable technique for evaluating anatomic heart disease in the late 1960s. Its earliest application involved detection of pericardial effusion and was soon followed by evaluation of valvular heart disease, most notably mitral stenosis. Its application in patients with coronary disease lagged substantially because of limitations of the earlier M-mode technique, which provided only a limited interrogation of the left ventricle, without the spatial orientation required for accurate diagnosis of wall motion abnormalities. With the introduction of clinical two-dimensional echocardiography in the late 1970s the ability to visualize all regions of the left ventricle, and to detect abnormal wall motion associated with myocardial ischemia or infarction was augmented tremendously. Subsequently, the technique began to see use in patients with known or suspected coronary disease. Initially, its use for this purpose was not widespread because of limitations of the narrow angle of the early scanners and sub-optimal image quality. With the development of newer generation imaging equipment, two-dimensional echocardiography now offers an unparalleled view of left ventricular anatomy and provides a simultaneous assessment of endocardial wall motion and myocardial thickening. Its tremendous versatility, relatively low cost, portability, and high degree of accuracy, make it an ideal tool in experienced hands for evaluating patients with known or suspected coronary disease. This includes patients with acute myocardial infarction, stable nonexertional chest pain syndromes, and chronic complications of myocardial ischemia. In this article the echocardiographic findings on which the diagnosis of coronary disease is made and many of the specific application in patients with coronary artery disease will be reviewed. Some of the newer, more specialized applications such as exercise echocardiography, direct coronary visualization, tissue characterization, and assessment of myocardial perfusion will also be discussed.
Evaluating Sources of Ego-Threatening Feedback: Self-Esteem and Narcissism Effects

Abstract High self-esteem individuals in previous studies have tended to deny the credibility of negative evaluators. The present research examined possible explanations for this finding and compared the effects of self-esteem and narcissism on evaluations of negative feedback sources. Following bogus negative feedback, self-esteem predicted negative evaluations of a nonperson feedback source and positive affect, as expected from consistency theory; narcissism predicted negative evaluations of a person feedback source and hostile affect, as expected from threat-derogation and narcissism theory. Results indicate the importance of distinguishing between healthy and defensive self-esteem in understanding responses to negative feedback.
Glycoprofiling of the Human Salivary Proteome

Glycosylation is important for a number of biological processes and is perhaps the most abundant and complicated of the known post-translational modifications found on proteins. This work combines two-dimensional polyacrylamide gel electrophoresis (2-DE) and lectin blotting to map the salivary glycome, and mass spectrometry to identity the proteins that are associated with the glycome map. A panel of 15 lectins that recognize six sugar-specific categories was used to visualize the type and extent of glycosylation in saliva from two healthy male individuals. Lectin blots were compared to 2-D gels stained either with Sypro Ruby (protein stain) or Pro-Q Emerald 488 (glycoprotein stain). Each lectin shows a distinct pattern, even those belonging to the same sugar-specific category. In addition, the glycosylation profiles generated from the lectin blots show that most of the salivary proteins are glycosylated and that the pattern is more widespread than is demonstrated by the glycoprotein stained gel. Finally, the co-reactivity between two lectins was measured to determine the glycan structures that are most and least often associated with one another along with the population variation of the lectin reactivity for 66 individuals.
C-Path: A Watson-Like Visit to the Pathology Lab

Computer-based quantification of tumor morphology has arguably solved the problem of standardized tumor grading (Beck et al., this issue).
Strengthening Intelligence Education with Information-Processing and Knowledge- Organization Competencies

This paper studies the weaknesses of intelligence-education curriculum in the United States from a Library and Information Science perspective. Intelligence information processing is a separate step in the traditional intelligence cycle; however, information-processing competencies are often included in the intelligence collection and analysis competencies in the Intelligence Community. A study of the websites of the intelligence-education programs in the major 27 intelligence-education institutions in the United States reveals that information processing is often implicitly included in an intelligence analysis or collection course; and only three universities offer such courses that include information-processing components. Only one university has been found to offer courses that implicitly include components of the knowledgeorganization competency. This paper recommends strengthening intelligence-education curriculum with information-processing and knowledge-organization competencies. This article is available in Journal of Strategic Security: http://scholarcommons.usf.edu/jss/vol6/iss3/2
Dysplastic nodules in cirrhotic liver: Arterial phase enhancement at CT and MR imaging - A case report

In a 65-year-old woman with cirrhosis, biphasic helical computed tomography (CT) and multiphase gadolinium-enhanced magnetic resonance (MR) imaging depicted 11 hepatic nodules that enhanced homogeneously during the hepatic arterial phase. At pathologic examination, all lesions were dysplastic nodules with unpaired hepatic arteries within. Hepatic arterial phase enhancement of cirrhotic nodules at CT and MR imaging is not diagnostic of hepatocellular carcinoma but may occur in dysplastic nodules. Results of a single biopsy yielding hepatocellular carcinoma may not be applicable to other nodules that enhance similarly.
Visualization Tools for Prescriptive Analysis of a Complex Adaptive System Model of Pilot Retention

This paper discusses a prototype agent-based simulation for examining United States Air Force pilot retention issues. The United States Air Force expends significant time and resources training pil...
Striosomal organization of cholinergic and dopaminergic uptake sites and cholinergic M1 receptors in the adult human striatum: a quantitative receptor autoradiographic study

The distribution of cholinergic pre- and postsynaptic markers and dopaminergic presynaptic markers was analyzed in the adult human striatum, using quantitative receptor autoradiography. The distribution of the different binding sites indicates that cholinergic and dopaminergic uptake sites display a striosomal organization, with a higher binding site density in the striatal matrix. M1 muscarinic cholinergic receptor distribution parallels the distribution of cholinergic presynaptic markers. Our data show that cholinergic and dopaminergic terminals, and M1 receptors are enriched in the matrix of the adult human striatum.
The surface electronic structure of oxygen on Pt(001)(1 × 1)

Abstract The surface embedded Green function (SEGF) method has been used to perform self-consistent calculations of the surface electronic structure of p(1 × 1) oxygen on Pt(001). The calculated O/Pt(001) work function is increased by 1.19 eV over the 5.92 eV previously obtained for clean Pt(001)(1 × 1). Both are in very good agreement with the experimental values of 1.0 ± 0.1 and 5.9 ± 0.1 eV, respectively. Our calculated difference-DOS curve is in good agreement with UPS difference spectra. Calculated surface state / surface resonance bands are compared with those obtained for Pt(001)(1 × 1) and for an isolated oxygen monolayer. Total and difference charge density plots are used to illustrate details of O-Pt bonding. Analysis of the surface charge density shows a reduction of surface stress upon oxygen chemisorption, indicating oxygen stabilization of the (1 × 1) phase.
Management of Energy Technology for Sustainability: How to Fund Energy Technology Research and Development

Operations management methods have been applied profitably to a wide range of technology portfolio management problems, but have been slow to be adopted by governments and policy makers. We develop a framework that allows us to apply such techniques to a large and important public policy problem: energy technology R&D portfolio management under climate change. We apply a multi-model approach, implementing probabilistic data derived from expert elicitations into a novel stochastic programming version of a dynamic integrated assessment model. We note that while the unifying framework we present can be applied to a range of models and data sets, the specific results depend on the data and assumptions used and therefore may not be generalizable. Nevertheless, the results are suggestive, and we find that the optimal technology portfolio for the set of projects considered is fairly robust to different specifications of climate uncertainty, to different policy environments, and to assumptions about the opportunity cost of investing. We also conclude that policy makers would do better to over-invest in R&D rather than under-invest. Finally, we show that R&D can play different roles in different types of policy environments, sometimes leading primarily to cost reduction, other times leading to better environmental outcomes.
Tumor blood volume: a prognostic biomarker for anaplastic astrocytomas?

Anaplastic astrocytoma is a WHO grade III glioma characterized by diffusely infiltrative astrocytic tumors with cytological atypia, anaplasia and mitoses [1]. Although histopathologic assessment remains the reference standard for tumor grading, sampling error, interand intrapathologist variability, and heterogeneity of gliomas may result in inadequate evaluation [2,3]. In particular, grade III gliomas tend to be heterogeneous and may contain regions of different degrees of malignant degeneration within the same tumor [4]. Therefore, imaging studies can provide additional characterization. While conventional MRI techniques can delineate the extent of the brain tumors, perfusion MRI can serve as an imaging biomarker. There are three main types of perfusion MRI techniques, including dynamic susceptibility contrast-enhanced magnetic resonance (MR) perfusion, dynamic contrast-enhanced MR perfusion and arterial spin-labeling MR perfusion [5]. Dynamic susceptibility contrast-enhanced MR perfusion consists of a bolus-tracking technique in which a bolus of gadolinium-based contrast agent through the brain is monitored by a series of T2or T2*-weighted MRI sequences. Dynamic contrast-enhanced perfusion MRI or permeability MRI is based on the acquisition of serial T1-weighted images before, during and after administration of contrast. Arterial spin-labeling MR perfusion uses magnetically labeled blood as an endogenous tracer and can be performed using continuous, pseudocontinuous or pulsed radiofrequency techniques. Dynamic susceptibility contrastenhanced MR perfusion in gliomas has been extensively studied and is used routinely in clinical practice. Using dynamic susceptibility contrast-enhanced MR perfusion, we recently investigated the perfusion characteristics of grade III tumors. Interestingly, there was no significant correlation (p = 0.12) between pretreatment tumor blood volume and progression-free survival for grade III tumors as a whole. However, further analysis revealed a significant correlation (p = 0.01) between pretreatment tumor blood volume and progression-free survival for the anaplastic astrocystoma subgroup. On the other hand, there was no significant correlation between pretreatment tumor blood volume and progression-free survival for oligo dendroglial tumors [6]. Furthermore,
Fixed-interval v as-needed analgesics in cancer outpatients

Abstract Many health professionals advocate medicating cancer patients in pain with fixed-interval analgesic schedules, but there is little research to support this approach. A pilot study in cancer outpatients was conducted to test the hypothesis that patients randomized to fixed-interval schedules of oral narcotic analgesics would report lower pain intensity than patients randomized to as-needed schedules. Twelve patients were randomized to fixed-interval and eight to as-needed schedules. They were followed for five consecutive days, recording amount and time they took analgesics, and rating pain intensity three times daily on a 10 cm visual analogue scale. A one-way repeated measures analysis of variance revealed no differences between the two groups of patients. Possible explanations for the findings include small sample size, unreliable measures of pain intensity, inadequate analgesic doses or intervals, or individual characteristics of the pain experience. Further research must address methodologic and measurement problems involved in the study of pain and its management to clarify the issue of analgesic scheduling in cancer outpatients.
Feminism found: An examination of gender consciousness in community psychology

Articles about women's issues published in the American Journal of Community Psychology and Journal of Community Psychology, from their inception in 1973 through 2000 were examined for feminist content. Feminism was defined as including consciousness of gender issues, gender-stratified power imbalances, and contextual analyses of gender. We identified 89 articles with feminist content. All 89 feminist articles were examined to identify themes of gender consciousness and intersecting identities. Within the theme of gender consciousness, we identified articles that addressed power asymmetries, the link between individuals and environments, contextual analyses, and a focus on competencies. Within the theme of intersecting identities, we identified articles that addressed race, class, sexual orientation, and disabilities. We discuss the trend toward more feminist research and explore ways create a feminist subdiscipline within the field of community psychology. Finally, we discuss recommendations for future feminist scholarship in the field. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 189–209, 2003.
Combining forecasts given different types of objectives

Abstract In this paper, two fundamentally different types of objectives - accuracy and direction of change - are incorporated into a multiple objective framework for combining forecasts. Most previous attempts at combining forecasts have focused on a single objective, usually some measure of forecast accuracy. While accuracy measures in terms of deviations between forecasted and actual values are more common, being able to predict correctly the direction of change, either increasing or decreasing in a variable of interest from one period to the next can be an important consideration also. Direction of change measures can be utilized to provide important additional information for decision making. Models including both types of objectives are developed, and solution strategies are discussed and illustrated. These enhanced models provide additional flexibility for decision makers without significantly increasing overall computational requirements.
Processing of highly elastomeric toughened cyanate esters through a modified resin transfer molding technique

Model cyanate ester resins containing different quantities of epoxy functional butadiene-acrylonitrile rubber (ETBN) to improve the fracture performance were developed as matrices for composites. With the elastomeric modification, the resin systems exhibited rheological characteristics inappropriate for laminate fabrication by conventional resin transfer molding (RTM). To fabricate the carbon fiber based laminates in one liquid molding operation successfully, a process named bleed resin transfer molding (BRTM) was established. The BRTM process combines features of RTM and resin film infusion processes (RFI) and was therefore appropriate for processing high viscosity matrix resins. A novel catalyst was selected for the cyanate ester resin that provided enough latency for the impregnation steps in the BRTM process. Through the use of thermal analytical tools, a high degree of phase separation and conversion was obtained. The conversion and the glass transition temperature were found not to decrease with increasing elastomer content, which is in contradiction to most toughening modifications. Mode I and Mode II interlaminar fracture toughness were found to increase significantly with increasing elastomer content. In Mode I, an increase of up to 140% was observed. Collectively, this work showed that through the use of the BRTM technique, matrices with toughness improvements usually only achieved by prepreg systems can be processed in an RTM-like manner.
The role of neutron activation analysis in the certification of NBS Standard Reference Materials

Neutron activation analysis (NAA) is used extensively at the National Bureau of Standards as one of the analytical techniques in the certification of Standard Reference Materials (SRMs). Characteristics of NAA which make it valuable in this role are: accuracy; multielemental capability; ability to assess homogeneity; high sensitivity for many elements, and essentially blank-free nature. Examples of recent SRM analyses illustrating these characteristics are described.
Accommodating latecomers in shared window systems

The X Teleconferencing and Viewing (XTV) X-based shared window system, which accommodates conference latecomers by monitoring the communication channel between a conference application and the initial user's display manager and recording the X resources created by a shared application, is described. XTV creates copies of the resources on a latecomer's X server when he or she joins the conference. The recording scheme used in XTV keeps minimal-length logs. >
Graphene: a versatile nanoplatform for biomedical applications

Graphene, with its excellent physical, chemical, and mechanical properties, holds tremendous potential for a wide variety of biomedical applications. As research on graphene-based nanomaterials is still at a nascent stage due to the short time span since its initial report in 2004, a focused review on this topic is timely and necessary. In this feature review, we first summarize the results from toxicity studies of graphene and its derivatives. Although literature reports have mixed findings, we emphasize that the key question is not how toxic graphene itself is, but how to modify and functionalize it and its derivatives so that they do not exhibit acute/chronic toxicity, can be cleared from the body over time, and thereby can be best used for biomedical applications. We then discuss in detail the exploration of graphene-based nanomaterials for tissue engineering, molecular imaging, and drug/gene delivery applications. The future of graphene-based nanomaterials in biomedicine looks brighter than ever, and it is expected that they will find a wide range of biomedical applications with future research effort and interdisciplinary collaboration.
Ionizing radiation and a wood-based biorefinery

Abstract Woody biomass is widely available around the world. Cellulose is the major structural component of woody biomass and is the most abundant polymer synthesized by nature, with hemicellulose and lignin being second and third. Despite this great abundance, woody biomass has seen limited application outside of the paper and lumber industries. Its use as a feedstock for fuels and chemicals has been limited because of its highly crystalline structure, inaccessible morphology, and limited solubility (recalcitrance). Any economic use of woody biomass for the production of fuels and chemicals requires a “pretreatment” process to enhance the accessibility of the biomass to enzymes and/or chemical reagents. Electron beams (EB), X-rays, and gamma rays produce ions in a material which can then initiate chemical reactions and cleavage of chemical bonds. Such ionizing radiation predominantly scissions and degrades or depolymerizes both cellulose and hemicelluloses, less is known about its effects on lignin. This paper discusses how ionizing radiation can be used to make a wood-based biorefinery more environmentally friendly and profitable for its operators.
Broadband orbital angular momentum manipulation using liquid crystal thin films

We introduce two high efficiency thin-film optical elements, operating over a wide spectral range, to generate and control the Orbital Angular Momentum (OAM) of various light sources: a broadband q-plate and a broadband Forked Polarization Grating (FPG). The broadband OAM manipulation is achieved by thin liquid crystal polymer layers that are aligned to provide the required spatially varying anisotropy. These elements operate using geometric phase principles to generate raised and lowered OAM modes whose efficiencies are sensitive to the polarization state of the incident light. We discuss the design principles involved and experimentally demonstrate broadband q-plates and FPGs that are highly efficient (> 90%) in the visible wavelength range. These thin film elements enable easy integration into various optical systems requiring broadband OAM manipulation such as optical trapping and high capacity information.
An exact solution for one-dimensional acoustic fields in ducts with an axial temperature gradient

Abstract In this paper an approach is presented for obtaining exact analytical solutions for sound propagation in ducts with an axial mean temperature gradient. The one-dimensional wave equation for ducts with an axial mean temperature gradient is derived. The analysis neglects the effects of mean flow, and therefore the solutions obtained are valid only for mean Mach numbers that are less than 0.1. The derived wave equation is then transformed to the mean temperature space. It is shown that by use of suitable transformations, the derived wave equation can be reduced to analytically solvable equations (e.g., Bessel’s differential equation). The applicability of the developed technique is demonstrated by obtaining a solution for ducts with a linear temperature profile. This solution is then applied to investigate the dependence of sound propagation in a quarter wave tube upon the mean temperature profile. Furthermore, the developed analytical solution is used to extend the classical impedance tube technique to the determination of admittances of high temperature systems (e.g., flames). The results obtained using the developed analytical solution are in excellent agreement with experimental as well as numerical results. Analytical solutions were also obtained for a duct with an exponential temperature profile and also for a temperature profile that corresponds to a constant convective heat transfer coefficient at the wall.
Asymptotic uniqueness of the sliding state for charge-density waves.

Analytic results are presented for the dynamic behavior of sliding charge-density waves (CDW's) and related extended nonlinear systems with randomness. It is shown that, in the limit of long times, a sliding configuration approaches a unique solution. In CDW models, the velocity of this asymptotic solution is periodic in time. These results explain previous numerical observations, simplify further analysis and simulation, and have direct experimental implications.
Exploring reversible reactions between CO2 and amines

Abstract The ‘old’ chemistry between CO 2 and primary alkylamines has been revisited. Amines 1 and 2 , with appended aromatic fluorophores, reversibly reacted with CO 2 in polar aprotic solvent (e.g. DMSO, DMF) with the formation of carbamic acids 3 and 4 . As a result, strong fluorescence occurred, thus directly reporting on the CO 2 entrapment. Carbamic acids were studied by 1 H and 13 C NMR spectroscopy in DMSO- d 6 . The carbamate bond, despite being covalent, is reversible and can be broken upon heating or simply flashing solutions with inert gases. Synthesis and evaluation of a CO 2 -sensing amino acid-α-naphthylglycine 7 is also reported for potential CO 2 monitoring under biorelevant conditions in aqueous solutions.
A Semi-Markovian Population Model with Application to Hospital Planning

A semi-Markovian population model can be used to describe patient movements in a health-care delivery system. The recovery progress of a patient at any time is defined by one of a finite number of "states." The movement of a patient among the states is governed by a discrete-time semi-Markov process which is called a " path." The inputs to the system are various patient "groups." Each group is characterized by a distinct input distribution with known mean and variance. Assuming that the input distributions are relatively stable in the long run, estimates of the means and variances of steady-state census mix are derived. On a short-term basis, the model will accommodate daily fluctuations in input distributions and use an information vector, which summarizes the state of the system at the time of prediction, to improve the estimation. An illustrative example using field data is presented.
Strain-induced crystallization of poly(ethylene terephthalate)

The fabrication of poly(ethylene terephthalate), PET, into fibers, films, and containers usually involves molecular orientation caused by molecular strain, which may lead to stress- or strain-induced crystallization (SIC). The SIC of PET was studied by the methods of birefringence, density, thermal analysis, light scattering, and wide-angle X-ray. The development of crystallinity is discussed in relation to the rate of crystallization, the residual degree of orientation, and stress relaxation. The experimental procedure involves stretching samples at temperatures above the glass transition temperature, Tg, to a given extension ratio and at a specific strain rate of an Instron machine. At the end of stretching, the sample is annealed in the stretched state and at the stretching temperature for various periods of time, after which the sample is quickly quenched to room temperature for subsequent measurements. During stretching, the stress strain and the stress relaxation curves are recorded. The results indicate that the SIC of annealed, stretched PET can proceed in three different paths depending on the residual degree of orientation. At a low degree of residual orientation, as indicated by the birefringence value, annealing of stretched PET leads only to molecular relaxation, resulting in a decrease of birefringence. At intermediate orientation levels, annealing causes an initial decrease in birefringence followed by a gradual increase and finally a leveling off of birefringence after a fairly long period of time. At higher orientation levels, annealing causes a rapid increase in birefringence before leveling off. The interpretation of the above results is made using the measurements of light scattering, differential scanning calorimetry, and wide-angle X-ray. The rate of the SIC of PET is also discussed in terms of specific data analysis.
Theory of the modified two stream instability in an MPD thruster

It is shown that for plasma parameters characteristic of those found in MPD thrusters, the modified two-stream instability may exist in the plasma. The critical parameter for triggering this instability is the ratio for the cross field current to the ion saturation current. Once triggered, this instability greatly increases the plasma resistivity to the flow of the current and heats both ions and electrons. The anomalous momentum exchange frequency and heating rates are calculated for characteristic MPD thruster parameters. 17 refs.
Temporal dynamics of semicircular canal and otolith function following acute unilateral vestibular deafferentation in humans

Dynamic changes of deficits in canal and otolith vestibulo-ocular reflexes (VORs) to high acceleration, eccentric yaw rotations were investigated in five subjects aged 25–65 years before and at frequent intervals 3–451 days following unilateral vestibular deafferentation (UVD) due to labyrinthectomy or vestibular neurectomy. Eye and head movements were recorded using magnetic search coils during transients of directionally random, whole-body rotation in darkness at peak acceleration 2,800°/s2. Canal VORs were characterized during rotation about a mid-otolith axis, viewing a target 500 cm distant until rotation onset in darkness. Otolith VOR responses were characterized by the increase in VOR gain during identical rotation about an axis 13 cm posterior to the otoliths, initially viewing a target 15 cm distant. Pre-UVD canal gain was directionally symmetrical, averaging 0.87 ± 0.02 (±SEM). Contralesional canal gain declined from pre-UVD by an average of 22% in the first 3–5 days post-UVD, before recovering to an asymptote of close 90% of pre-UVD level at 1–3 months. This recovery corresponded to resolution of spontaneous nystagmus. Ipsilesional gain declined to 59%, and showed no consistent recovery afterwards. Pre-UVD otolith gain was directionally symmetrical, averaging 0.56 ± 0.02. Immediately after UVD, the contralesional otolith gain declined to 0.30 ± 0.02, and did not recover. Ipsilesional otolith gain declined profoundly to 0.08 ± 0.03 (P < 0.01), and never recovered. In contrast to the modest and directionally symmetrical effect of UVD on the human otolith VOR during pure translational acceleration, otolith gain during eccentric yaw rotation exhibited a profound and lasting deficit that might be diagnostically useful in lateralizing otolith pathology. Most recovery of the human canal gain to high acceleration transients following UVD is for contralesional head rotation, occurring within 3 months as spontaneous nystagmus resolves.
Neural systems for compensation and persistence: young adult outcome of childhood reading disability.

Abstract Background This study examined whether and how two groups of young adults who were poor readers as children (a relatively compensated group and a group with persistent reading difficulties) differed from nonimpaired readers and if there were any factors distinguishing the compensated from persistently poor readers that might account for their different outcomes. Methods Using functional magnetic resonance imaging, we studied three groups of young adults, ages 18.5–22.5 years, as they read pseudowords and real words: 1) persistently poor readers (PPR; n = 24); 2) accuracy improved (compensated) readers (AIR; n = 19); and 3) nonimpaired readers (NI, n = 27). Results Compensated readers, who are accurate but not fluent, demonstrate a relative underactivation in posterior neural systems for reading located in left parietotemporal and occipitotemporal regions. Persistently poor readers, who are both not fluent and less accurate, activate posterior reading systems but engage them differently from nonimpaired readers, appearing to rely more on memory-based rather than analytic word identification strategies. Conclusions These findings of divergent neural outcomes as young adults are both new and unexpected and suggest a neural basis for reading outcomes of compensation and persistence in adults with childhood dyslexia.
Spatial variation in diurnal surface temperatures and the distribution and abundance of an alpine grasshopper

We studied the influence of spatial differences in diurnal surface temperatures due to topography on an alpine grasshopper (Aeropedellus clavatus). Temperature measurements on east-and west-facing alpine dry meadow slopes on Niwot Ridge in Colorado demonstrated a significant difference in diurnal surface temperatures between the two slopes throughout the growing season. A. clavatus body temperature was found to be highly correlated with nearby shaded surface temperature, and individual grasshoppers enclosed on the two slopes had significantly higher relative growth rates on the warmer east slope. Temperature effects were manifest at the population level as well. A. clavatus was significantly more abundant on the east-facing than on the west-facing slope, despite similar vegetation in both areas. This study contributes to our understanding of the myriad of factors governing insect distribution and abundance by attempting to integrate the physiological and ecological, abiotic and biotic, influences on both individuals and populations.
Lipid Raft-Mediated Regulation of G-Protein Coupled Receptor Signaling by Ligands which Influence Receptor Dimerization: A Computational Study

G-protein coupled receptors (GPCRs) are the largest family of cell surface receptors; they activate heterotrimeric G-proteins in response to ligand stimulation. Although many GPCRs have been shown to form homo- and/or heterodimers on the cell membrane, the purpose of this dimerization is not known. Recent research has shown that receptor dimerization may have a role in organization of receptors on the cell surface. In addition, microdomains on the cell membrane termed lipid rafts have been shown to play a role in GPCR localization. Using a combination of stochastic (Monte Carlo) and deterministic modeling, we propose a novel mechanism for lipid raft partitioning of GPCRs based on reversible dimerization of receptors and then demonstrate that such localization can affect GPCR signaling. Modeling results are consistent with a variety of experimental data indicating that lipid rafts have a role in amplification or attenuation of G-protein signaling. Thus our work suggests a new mechanism by which dimerization-inducing or inhibiting characteristics of ligands can influence GPCR signaling by controlling receptor organization on the cell membrane.
Continuous venovenous hemofiltration and hemodialysis after orthotopic heart transplantation

Orthotopic heart transplantation (OHT) is an accepted treatment for heart failure refractory to medical management. International registry data reported a 1-year survival after OHT of 79%. The risk factors associated with requiring continuous venovenous hemofiltration or hemodialysis and mortality in patients requiring continuous venovenous hemofiltration (CVVH)/hemodialysis (HD) have not been studied, since improvements have been made in OHT. We tested the hypothesis that requiring CVVH/HD in the immediate posttransplantation period increases mortality after OHT. We studied pretransplantation factors to predict those patients who would need CVVH/HD. Patients undergoing OHT from 1995 to 1996 were studied. Fifty-two patients underwent OHT. Eight patients (15%) needed CVVH/HD. Initial immunosuppression included cyclosporine, azathioprine, and solumedrol. Patients were changed to antilymphocyte therapy if they had oliguric acute renal failure, T or B cell incompatibility, or biopsy-proven rejection. Overall, survival at 1 year was 84.6%. Survival in patients not needing CVVH/HD was 91%, and survival in patients needing CVVH/HD was 36.5%. For each year of age over 55 years, patients had a relative risk of requiring CVVH/HD of 7.
Differences in diet and feeding ecology of similar‐sized spotted (Lepisosteus oculatus) and shortnose (Lepisosteus platostomus) gars during flooding of a south‐eastern US river

Connection events between rivers and their adjacent floodplains can alter availability of resources. Riverine fishes opportunistically exploit seasonally available resources during periods of high water. Gars are known to utilize floodplain habitats throughout different life stages for spawning and feeding. Food habits of gars have been the focus of many studies; however, less is known regarding the partitioning of food resources between syntopic species overlapping in body size. Further, little information exists on food resources of shortnose gar, Lepisosteus platostomus. We report results of diet analysis of spotted, Lepisosteus oculatus, and shortnose gar from the Fourche LaFave River in central Arkansas. Stomachs were examined from 74 adult spotted gar (46–81 cm TL) and 91 adult shortnose gar (49–76 cm TL) collected between May and July 2007 during flooding. Forty-seven (64%) spotted and 54 (59%) shortnose gar contained identifiable prey items. Spotted and shortnose gars had low diet overlap (33.0%), indicating these two species partition food resources. Considering percent composition by weight (%Cw), spotted and shortnose gar appear to partition available food resources during summer flooding. Percent composition by weight of fishes and crustaceans was significantly greater in the diet of spotted gar than shortnose gar (Table 2). Shortnose gar had significantly greater %Cw of amphibians and terrestrial invertebrates compared to spotted gar. It is likely that the seasonal and consistent annual availability of terrestrial subsidies to the system holds a unique importance for the shortnose gar population.
Labour‐management partnerships: Interpretive strategies in workplace change

(1998). Labour‐management partnerships: Interpretive strategies in workplace change. Science as Culture: Vol. 7, Strategizing counter-expertise, pp. 243-263.
A clinical study of the apple diet in the treatment of diarrhea in infants

Summary In the past summer ninety cases of diarrhea, fifty in the hospital and forty in the dispensary, were studied, and an attempt was made to compare the results of apple therapy with other methods in the treatment of diarrhea. 1. Apple diet was of no value in the treatment of dysentery. 2. In both mild and severe types of diarrhea in infants the results obtained with apple therapy were no better than those obtained in any other type of treatment. 3. Any beneficial results obtained from the use of apple diet were due to the period of starvation and the rest induced in the gastrointestinal tract by the bland nonirritating qualities of the apples. 4. The care of diarrheas depends on rest for the gastrointestinal tract, parenteral fluids, supportive measures, and maintenance of the mineral balance.
Vehicle routing algorithms to intercept escaping targets

We study a dynamic vehicle routing problem for moving targets. Our setup is as follows: (i) targets appear uniformly distributed on a unit disk via a temporal Poisson process and move radially outward with a constant speed v, (ii) a single vehicle with speed greater than that of the targets aims to intercepts them before they escape the disk. With the goal of maximizing the fraction of captured targets in the steady state, we propose three policies: Capturable Nearest Neighbor (CNN), Sector Wise (SW) and Stay Near Boundary (SNB) policy. We derive lower bounds on the fraction of targets captured by the CNN, SW and SNB policies. The CNN policy is shown to be optimal for arrival rate λ below a critical value. For arrival rates above another critical value, the fraction of targets captured by the SW policy is more than that of the CNN policy. Finally, the SNB policy is within a constant factor of optimal in the limiting regime of ν → 0 + and λ → +∞. We present numerical simulations to illustrate our results.
Multi-period bargaining: asymmetric information and risk aversion

Abstract A two period bargaining model with asymmetric information is considered. An uninformed seller charges a uniform price to two buyers. A risk averse seller offers a larger price cut in period two when one buyer remains in the market than when two buyers remain. The price in period one is sensitive to the number of buyers and the seller’s degree of risk aversion. The initial price charged to a single buyer may be higher or lower than the price charged to two buyers, depending on the degree of seller risk aversion.
Translocation of cortactin to the cell periphery is mediated by the small GTPase Rac1

Small GTPases of the Rho family regulate signaling pathways that control actin cytoskeletal structures. In Swiss 3T3 cells, RhoA activation leads to stress fiber and focal adhesion formation, Rac1 to lamellipoda and membrane ruffles, and Cdc42 to microspikes and filopodia. Several downstream molecules mediating these effects have been recently identified. In this report we provide evidence that the intracellular localization of the actin binding protein cortactin, a Src kinase substrate, is regulated by the activation of Rac1. Cortactin redistributes from the cytoplasm into membrane ruffles as a result of growth factor-induced Rac1 activation, and this translocation is blocked by expression of dominant negative Rac1N17. Expression of constitutively active Rac1L61 evoked the translocation of cortactin from cytoplasmic pools into peripheral membrane ruffles. Expression of mutant forms of the serine/threonine kinase PAK1, a downstream effector of Rac1 and Cdc42 recently demonstrated to trigger cortical actin polymerization and membrane ruffling, also led to the translocation of cortactin to the cell cortex, although this was effectively blocked by coexpression of Rac1N17. Collectively these data provide evidence for cortactin as a putative target of Rac1-induced signal transduction events involved in membrane ruffling and lamellipodia formation.
Persistent Aortic Arch Hypoplasia After Coarctation Treatment Is Associated With Late Systemic Hypertension.

Background Mild transverse aortic arch (TAA) hypoplasia is common after coarctation treatment, but is considered benign in the absence of an arm‐leg systolic blood pressure (SBP) difference. Hypertension (HTN) is a common long‐term morbidity after successful coarctation treatment. We examined whether mild TAA hypoplasia after coarctation treatment is associated with late systemic HTN. Methods and Results We retrospectively reviewed 92 patients (median age, 19.9 years; range, 4.9 to 57.8; 60% male) 14.1±10.3 years after successful coarctation treatment (surgery in 63, stent in 16, and balloon dilation in 13), excluding those with resting right arm‐leg blood pressure gradient >20 mm Hg, atypical coarctation, and major associated heart defects. Minimum body‐surface area (BSA)‐adjusted TAA cross‐sectional area (CSA) was calculated from cardiac magnetic resonance (CMR) images. On follow‐up, 38 of 92 (41%) patients had systemic HTN using standard criteria. Systemic HTN was independently associated with smaller TAA CSA/BSA ( P =0.006; odds ratio [OR], 6.41 per 0.5 cm2/m2 decrease), higher age at CMR ( P =0.03; OR, 1.57 per 5‐year increase), and in a subset (n=61), higher arm‐leg SBP difference during exercise ( P =0.05; OR, 1.03 per 1‐mm‐Hg increase). Lower ratio of TAA diameter/descending aorta diameter was associated with a larger increase in right arm SBP during peak exercise ( P =0.006; r 2=0.11). Conclusions Persistent mild aortic arch hypoplasia, even in the absence of an arm‐leg SBP difference at rest, is associated with late systemic HTN. Further studies should be undertaken to determine whether more‐aggressive arch reconstruction at initial repair can reduce the incidence of systemic HTN.