cssi/SciSciGPT-SciSciNet huggingface dataset:
An Antagonistic Flexural Unit Cell for Design of Shape Morphing Structures

An antagonistic flexural unit cell (AFC) concept for the design and fabrication of novel 2-D and 3-D lightweight shape morphing structures is introduced. A fully reversible flexural shape changing cell utilizing opposing one-way shape memory alloy (SMA) actuators is shown to require no spring-like bias elements. The SMA actuating elements are arranged such that the actuation (contraction) of one of them stretches the other one in the cell, preparing it to be actuated later to reverse a flexural displacement. This antagonistic operation allows fully reversed cyclic operation. The focus of this paper is an assessment of performance at the single cell level. The cell logically provides four possible configurations in different stages of its cycle. Two of them are of particular interest because they provide two different fixed shapes for the cell that can be maintained without the continuous supply of external energy. The final deformations of the cell and equilibrium stresses in the SMA elements depend on the amount of stored shape memory strain in each element, external forces and cell geometry. A model is developed, which allows a full characterization of the AFC. The model is used to study NiTi SMA-based AFCs and the results are therefore directly applicable to the design of shape morphing structures using such unit cells.Copyright © 2004 by ASME
Humans Rapidly Learn Grammatical Structure in a New Musical Scale

Knowledge of musical rules and structures has been reliably demonstrated in humans of different ages, cultures, and levels of music training, and has been linked to our musical preferences. However, how humans acquire knowledge of and develop preferences for music remains unknown. The present study shows that humans rapidly develop knowledge and preferences when given limited exposure to a new musical system. Using a non-traditional, unfamiliar musical scale (Bohlen-Pierce scale), we created finite-state musical grammars from which we composed sets of melodies. After 25–30 min of passive exposure to the melodies, participants showed extensive learning as characterized by recognition, generalization, and sensitivity to the event frequencies in their given grammar, as well as increased preference for repeated melodies in the new musical system. Results provide evidence that a domain-general statistical learning mechanism may account for much of the human appreciation for music.
The occurrence and development of Plasmodium mexicanum in the western fence lizard Sceloporus occidentalis.

SYNOPSIS. From various localities in California, 81 (21%) of 381 Sceloporus occidentalis were found infected with Plasmodium mexicanum. Variations in asexual reproduction and host response during the acute period of development are discussed. Appearance of initial infections in early March and the subsequent increase in natural incidence of the parasite, the absence of infections in hatchlings, and the persistence of numerous gametocytes in hibernating lizards suggest a period of spring transmission.
A designed four helix bundle protein with native-like structure.

A 108 amino acid protein was designed and constructed from a reduced alphabet of seven amino acids. The 2.9 A resolution X-ray crystal structure confirms that the protein is a four helix bundle, as it was designed to be. Hydrogen/deuterium exchange experiments reveal buried amide protons with protection factors in excess of 1 × 106 in the range characteristic of well protected protons in functional folded proteins (103–108) rather than protons in rapid exchange (0–102). The protein is monomeric at 1 mM, the concentration at which the exchange experiments were undertaken, indicating that the exchange factors are due to a unique stable tertiary structure fold, and not due to any higher order quaternary structure. Thermodynamic analysis provides an estimate of the free energy of folding of −9.3 kcal mole−1 at 25 °C, consistent with the free energy of folding derived from the protection factors of the most protected protons, indicating that global unfolding is required for exchange of the most protected protons.
Global sea-level changes and the thermal structure of the earth

Abstract There is good evidence that the major changes of sea level over the past 500 m.y. have been caused by changes in the volume of the oceanic ridge system. Increases in ridge volume result from both increases in the length of the ridge system and increases in spreading rates. Using the thermal boundary layer theory for the thermal structure and subsidence of oceanic ridges, the ridge volume is related to the ridge heat flow. In this paper, the observations on paleo-sea level are used to infer variations in the ridge heat flow over the last 500 m.y. The ridge contribution to the total surface heat flow has varied between about 25% and 50% or more of the total. Since periods of rapid plate accretion must correspond to periods of rapid plate consumption, and orogenic phenomena are mainly associated with plate consumption, it is likely that high sea levels will prove to be the best indicators of the episodicity of orogeny.
Diffuse scattering and image contrast of tweed in superconducting oxides: simulation and interpretation

Abstract Monte Carlo simulations were performed with a lattice gas model to represent the interactions between oxygen atoms in the YBa2(Cu1-xMx)3O7+δ (M = Fe, Co or Al, 0.03
Discontinuity-Preserving Surface Reconstruction Using Stochastic Differential Equations

We address the problem of reconstructing a surface from irregularly spaced sparse and noisy range data while concurrently identifying and preserving the significant discontinuities in depth. It is well known that, starting from either the probabilistic Markov random field model or the mechanical membrane or thin plate model for the surface, the solution of the reconstruction problem can be eventually reduced to the global minimization of a certain “energy” function. Requiring the preservation of depth discontinuities makes the energy function nonconvex and replete with multiple local minima. We present a new method for obtaining discontinuity-preserving reconstruction based on the numerical solution of an appropriate Ito vector stochastic differential equation (SDE). The reconstructed surface is found by following the sample path of the (stochastic) diffusion process that solves the SDE in question. Our central contribution is the demonstration of the efficacy of the stochastic differential equation technique for solving a vision problem. Through comparisions of the results of our method to those of the two well-known existingglobalminimization based reconstruction techniques, we show a significant improvement in the final reconstructions obtained.
Relation of Body Mass Index to On-Treatment (Clopidogrel + Aspirin) Platelet Reactivity

Previous research has suggested that obesity is associated with increased high on-treatment platelet reactivity. We therefore tested platelet reactivity in 251 patients with VerifyNow P2Y12, vasodilator-stimulated phosphoprotein phosphorylation, and light transmission aggregometry with adenosine diphosphate 5 and 20 μM 6 to 24 hours after percutaneous coronary intervention. High on-treatment platelet reactivity was defined as a maximum platelet aggregation ≥46% for light transmission aggregometry with adenosine diphosphate 5 μM or ≥60% for 20 μM, platelet reactivity index ≥50% for vasodilator-stimulated phosphoprotein phosphorylation, and P2Y12 reaction units ≥235 for VerifyNow. The relation between body mass index (BMI) and platelet reactivity values was examined with Spearman coefficients; BMI and high on-treatment platelet reactivity were assessed with Student's t test. Multivariable logistic regression for high on-treatment platelet reactivity was also performed. Average BMI was 30.3 ± 5.9 kg/m² and 44% of patients had a BMI ≥30 kg/m². Overall there was very poor correlation between BMI and on-treatment platelet reactivity, with Spearman coefficients ranging from 0.08 to 0.10. BMI was also not associated with the various definitions of high on-treatment platelet reactivity. Multivariable logistic regressions showed no association between BMI and high on-treatment platelet reactivity. In conclusion, and contrary to previous reports, we found no association whatsoever between BMI and on-treatment platelet reactivity as quantified by a variety of platelet function tests.
Molecular dynamics simulation study of nonlinear optical response of fluids

Abstract We present a molecular theory and molecular dynamics simulation of the transient nonlinear optical response measured in impulsive stimulated light scattering (ISS) and optical Kerr effect (OKE) experiments. The dipole-induced-dipole model is used to calculate the interaction-induced polarizability and ISS and OKE dynamic response functions of liquid CS 2 and compressed supercritical CO 2 . We find that rotational relaxation dominates the long-time response and that “collision-induced” polarizability dynamics influences strongly the subpicosecond response of both fluids. These “collision-induced” effects are emphasized in the ISS signal, where they account for most of the peak intensity in the case of the highly polarizable CS 2 .
Limits of superradiance as a process for achieving short pulses of high energy

This paper augments previous theoretical descriptions of superradiance in an extended optically thick medium by giving expressions which limit the length and density of a high-gain system which can superradiate as a whole, or equivalently, the shortness of its output radiation pulses. Limits arising from experimental conditions such as finite inversion time, finite decay and dephasing times, finite transit time (cooperation length), feedback, diffraction, and Fresnel number not approximately one, are discussed. Modifications to the simple analytical expressions for the output radiation of the superradiant system due to each of these effects are described in detail. Detailed computer results are also given.
Depth determination of chromophores in human skin by pulsed photothermal radiometry

We report on the application of pulsed photothermal radiometry (PPTR) to determine the depth of in-vitro and in-vivo subsurface chromophores in biological materials. Measurements provided by PPTR in combination with a nonnegative constrained conjugate-gradient algorithm are used to determine the initial temperature distribution in a biological material immediately following pulsed laser irradiation. Within the experimental error, chromophore depths (50-450 µm) in 55 in-vitro collagen phantoms determined by PPTR and optical low-coherence reflectometry are equivalent. The depths of port-wine-stain blood vessels determined by PPTR correlate very well with their locations found by computer-assisted microscopic observation of histologic sections. The mean blood-vessel depth deduced from PPTR and histologic observation is statistically indistinguishable (p > 0.94).
Simulation of Five Load-Shedding Schedules

Results of a simulation study of five different load- shedding schedules using a comprehensive long-term dynamic simulator are presented. Insight is provided into the effectiveness of underfrequency load shedding, and the important factors to consider in establishing a load-shedding schedule are discussed.
A Mitochondrial Oscillator Dependent on Reactive Oxygen Species

We describe a unique mitochondrial oscillator that depends on oxidative phosphorylation, reactive oxygen species (ROS), and mitochondrial inner membrane ion channels. Cell-wide synchronized oscillations in mitochondrial membrane potential (Delta Psi(m)), NADH, and ROS production have been recently described in isolated cardiomyocytes, and we have hypothesized that the balance between superoxide anion efflux through inner membrane anion channels and the intracellular ROS scavenging capacity play a key role in the oscillatory mechanism. Here, we formally test the hypothesis using a computational model of mitochondrial energetics and Ca(2+) handling including mitochondrial ROS production, cytoplasmic ROS scavenging, and ROS activation of inner membrane anion flux. The mathematical model reproduces the period and phase of the observed oscillations in Delta Psi(m), NADH, and ROS. Moreover, we experimentally verify model predictions that the period of the oscillator can be modulated by altering the concentration of ROS scavengers or the rate of oxidative phosphorylation, and that the redox state of the glutathione pool oscillates. In addition to its role in cellular dysfunction during metabolic stress, the period of the oscillator can be shown to span a wide range, from milliseconds to hours, suggesting that it may also be a mechanism for physiological timekeeping and/or redox signaling.
Women in Hong Kong . Edited by Veronica Pearson and Benjamin K. P. Leung. New York: Oxford University Press, 1995. xvii, 301 pp. $27.00 (cloth).

Despite the post-war economic boom that brought Hong Kong into the first rank of wealthy societies, gender discrimination is still widespread in the territory. The ten essays collected here discuss various aspects of gender relations and gender inequality in the territory, addressing such diverse issues as education, industrialization, the sex industry, and relations within the family.
Eliciting patients' preferences for cigarette and alcohol cessation: an application of conjoint analysis.

The strength and stability of preferences for quitting cigarettes versus alcohol in a population of dual users undergoing treatment was examined using conjoint analysis. Patients at a Veteran's Administration substance abuse treatment center ranked nine vignettes from most to least preferred at baseline and 4 weeks later. The vignettes, using a full factorial design, described health states associated with three levels of substance use. We regressed vignette rankings on the levels of smoking and drinking. A larger regression coefficient indicated a stronger preference for quitting. At baseline and follow-up, the group placed more preference on quitting alcohol than cigarettes (coefficients of 2.23 and 2.35 for alcohol cessation and .51 and .73 for smoking cessation). Some subjects preferred smoking to quitting at baseline (23.9%) and follow-up (23.5%). Over time, 29.4% and 35.3% increased their preference for tobacco and alcohol cessation, while 41.2% and 17.6% decreased their preference for cigarette and alcohol cessation. Preferences for stopping alcohol were stronger than for stopping cigarettes, and many preferences changed after a treatment program.
Characterization of plant phenotypes associated with loss-of-function of AtCNGC1, a plant cyclic nucleotide gated cation channel

Of the 57 cation channel genes in the Arabidopsis genome, over a third encode cyclic nucleotide gated cation channels (CNGCs). CNGCs are ion channels regulated by cytosolic signaling molecules (cyclic nucleotides, calmodulin, and Ca(2+)), and which conduct Ca(2+) as well as K(+) and in some cases Na(+). Little is currently known about the role CNGCs may play in plant growth and development. Here, we examined the hypothesis that an Arabidopsis thaliana genotype containing a null mutation in one of the CGNC genes (AtCNGC1) would display cation uptake-related growth phenotype differences from wild type (WT) plants. We determined that AtCNGC1 protein is primarily expressed in the roots of Arabidopsis seedlings. Seedlings lacking this protein had slightly (6-22%) lower shoot Ca(2+) than WT plants. Primary roots of Atcngc1 mutant seedlings grew faster than roots of WT plants, and had larger angles of gravicurvature and less nitric oxide generation upon gravistimulation. We conclude that channels formed (at least in part) by AtCNGC1 contribute (along with other channels) to Ca(2+) uptake into plants, and that Ca(2+) uptake into roots through AtCNGC1 affects some aspects of growth in the primary root of Arabidopsis seedlings.
Heterotopic oral gastrointestinal cystReport of 2 cases and review of the literature

Abstract Oral heterotopic gastrointestinal cyst is a rare entity occurring in infants and children and showing a predilection for males. The cyst usually appears as an asymptomatic swelling in the floor of the mouth. Difficulty in feeding, swallowing, respiration, and speech have been reported in approximately 30% of those affected. The tongue—in particular, its anterior aspect—is involved in up to 60% of reported cases. The clinical, radiographic, and histopathologic features of cases of heterotopic gastrointestinal cyst involving the anterior tongue in a 2-year-old girl and the anterior floor of the mouth in a 2-month-old boy are presented, and theories of pathogenesis are discussed. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;88: 80-6)
A design for one millimeter pitch multiware proportional chambers operating at high rates

Abstract The design of two 1 mm pitch multiwire proportional chambers is described. Each chamber has an active area of 220 mm × 600 mm. Details are provided about the mechanical design of the chambers, design of the high voltage system, and design of the dc coupled amplifiers. The choice of amplifier input impedence and threshold is discussed. A measurement of the chamber gas deadtime is presented, and several gas mixtures are evaluated.
A further application of composite-stimulus control in additive summation

Six rats were trained to leverpress on a three-component multiple schedule containing variable-interval (VI) 28-sec, VI 66-sec, and extinction components. Under this arrangement all subjects came to respond during the VI periods, while responding essentially ceased in the extinction associated stimulus. Tone and light (T + L) were both present during the VI 28-sec contingency and both were absent (tone off and light out, T + L) during the VI 66-sec contingency. For half the rats extinction was programmed in light (L + T), for the other half extinction was programmed in tone (T + L). A composite-stimulus analysis of the training conditions reveals that, for the L + T extinction rats, the composite composed entirely of stimulus elements associated with responding was T + L (tone), while for the T + L extinction rats this stimulus was L + T (light). In testing all subjects emitted the most responses to that composite stimulus composed entirely of elements discriminative for responding, rather than to the VI associated composites that had an element in common with the extinction component. That it was tone or light to which the subjects showed additive summation supports predictions from Weiss’ (1969, 1972) composite-stimulus control model.
Carbon K-edge X-ray absorption fine structures of ethylene and acetylene adsorbed onto nickel(II) surface

Abstract The carbon K-edge X-ray absorption spectra of ethylene and acetylene adsorbed on a Ni(111) surface at 300 K exhibit C(1s) to π * and σ shape-resonance transitions. The polarization dependence of the π * and σ resonances and their energies are used to infer that the adsorbed species has an unsaturated carbon-carbon bond, regardless of whether the adsorbate was C 2 H 2 or C 2 H 4 , and that the molecular axis of the adsorped species is parallel to the surface.
Mapping dynamic branch displacements: a versatile method to quantify spatiotemporal neurite dynamics.

Abstract Quantification of the movement of axons and dendrites is essential to study circuit formation. Several methods have been developed to quantify the movement of neurites in simplified systems, however these quantification methods are specialized for a limited type of predicted movements in the particular assay systems. The movement of neurites in vivo includes many unexpected rearrangements. Establishment of a method that can detect and quantify a variety of patterning events will reveal novel phenomena in circuit formation and make it possible to conduct deeper investigation of the molecular and cellular bases of these events. Here we present a versatile method that represents a quantitative analysis of the integrated movement of neurites on a spatial map. We show that the method is useful to analyze several types of neurite behaviors, such as changes in the directionality of neurite movements, fasciculation of axons or changes in territories of dendritic fields.
Extraction of somatostatin by the pancreas.

Pancreatic somatostatin has been postulated to be a paracrine or local modulator of islet function. Other locally released modulators, such as the sympathetic neurotransmitter norepinephrine, are known to be extracted by local tissues. Therefore, we hypothesized that somatostatin, in addition to being released from islet D-cells, might also be partially extracted by pancreatic tissue. To test the concept that the pancreas is capable of extracting somatostatin, exogenous somatostatin-14 was infused into the femoral vein, and the increments of somatostatin- like immunoreactivity in arterial plasma were compared to those in pancreatic venous plasma. Extraction of somatostatin- 14 by the in situ dog pancreas averaged greater than 50%, whereas extraction of another pancreatic peptide, glucagon, was less than 17%. We conclude that the pancreas extracts significant quantities of exogenous somatostatin-14.
Self-Adjusting Fluency Therapy

The purpose of this paper is to describe a rationale and methodology for a self-adjusting approach to working with children, which we called “fluency sensitive”. These techniques may be applied as a component of a therapy program for preschoolers and school aged children who exhibit overt fluency interruptions and a minimal amount of avoidance behavior. The goal of this approach is to help children integrate fluency enhancing speech adjustments by repeatedly experiencing the effects of volitional increases and decreases in loudness and pausing. Case examples are presented to demonstrate how several fluency sensitive children responded to this approach. The paper concludes with a discussion of issues related to the nature of change in self-adjusting therapy. To begin, we describe the nature of fluency and fluency sensitivity.
Nonparametric Prediction of Event Times for Analysis of Failure-Time Data

In trials with failure-time outcomes, statistical information is determined by accumulated events. Interim and final analyses are performed after a prespecified number of events have been observed. It is of interest to predict when a prespecified number of events will be observed based on accumulating data. We propose a fully Bayesian nonparametric approach in modeling the survival probabilities. We compare the accuracy and precision of this approach to proposed parametric and semi-parametric methods. In summary, the proposed method offers greater flexibility and based on our studies has the ability to match or outperform existing methods.
LA INTERACTIVIDAD EN LA EDUCACION A DISTANCIA: EVALUACION DE COMUNIDADES DE APRENDIZAJE

Computer technology and the Internet allow for increased interactivity in distance education. On- line learning communities are being created. Students are engaging in discourse, and socially con- structed learning is taking place. Socially constructed learning cannot be packaged in neatly defined learning goals. It is hard to measure whether the discourse amongst the learners truly generates new skills, insights, and know- ledge and in what ways the features of the virtual site support the learning process. The paper explores the format of selected online distance learning spaces for teachers, presents possible evaluation criteria, and discusses the applicability of the criteria to the evaluation of such a variable distance education format.
The Importance of Nongenetic Influences on Romantic Love Styles: A Twin-Family Study

Research in several disciplines reveals large individual differences in orientations to romantic love, yet the origins of the differences have been unclear In this first behavior genetic study of romantic love, biometric model fitting reveals that in contrast to other personality and attitude domains, where genetic factors account for approximately 50% of the reliable variance and shared environment has little effect, individual differences in romantic love are due almost exclusively to environment Moreover, the common family environment plays a sizable role in determining love styles, a finding compatible with theories stressing the importance of family inter-actions in personality development
Localized excitatory synaptic interactions mediate the sustained depolarization of electrographic seizures in developing hippocampus

Repetitive synchronized neuronal discharging that lasts for seconds and even minutes in in vitro brain slice preparations are important new models in experimental epilepsy. In hippocampal slices from 1–2-week- old rats, individual CA3 pyramidal cells undergo a sustained depolarization during such electrographic seizures, induced by GABAA receptor antagonists. In experiments reported here these events were produced in small isolated segments of the CA3 subfield, measuring only 400–500 microns along the cell body layer. In such minisclices local application of either kynurenic acid or 6-cyano-7-nitroquinoxaline-2–3- dione (CNQX) to the proximal basilar dendrites abolished the synchronized discharges of electrographic seizures. Interictal spikes appeared unaffected by this treatment. Application of these excitatory amino acid receptor antagonists to distal basilar dendrites or apical dendrites was ineffective. In “larger” minislices, measuring 700–1000 microns along the cell body layer, application of kynurenic acid, CNQX, or TTX to the proximal basilar dendrites did not abolish electrographic seizures but instead selectively suppressed the intracellularly recorded sustained depolarization and the coincident slow negative field potential recorded in proximal basilar dendrites. Results of several experiments suggest that electrographic seizures recorded under these conditions were produced by a remote network of “generator cells.” Since the remote neurons were unaffected by local application of the drugs, it seemed likely that they continued to undergo a sustained depolarization. Simultaneous blockade of basilar dendritic synapses in the “generator” population abolished electrographic seizures throughout these larger minislices. These results suggest that the sustained depolarization plays a central role in seizure generation and that it does not have to be generated in every neuron, only in a critical number of “generator cells” for a seizure to occur. Taken together, results presented here suggest that the sustained depolarization of electrographic seizures is a separate physiological process from the more rapid repetitive depolarizations of the seizure discharges and is required if electrographic seizures are to occur. This slow depolarization appears to be synaptically mediated and generated exclusively in proximal basilar dendrites. Therefore, in addition to the excitatory synaptic potentials involved in paroxysmal depolarization shift generation, a second form of recurrent excitation may exist in immature hippocampus. Not only is this physiological process critical for the genesis of seizures, but it also appears to be highly partitioned within the hippocampal laminae.
The dissipation approximation and viscous potential flow

Dissipation approximations have been used to calculate the drag on bubbles and drops and the decay rate of free gravity waves on water. In these approximations, viscous effects are calculated by evaluating the viscous stresses on irrotational flows. The pressure is not involved in the dissipation integral, but it enters into the power of traction integral, which equals the dissipation. A viscous correction of the irrotational pressure is needed to resolve the discrepancy between the zero-shear-stress boundary condition at a free surface and the non-zero irrotational shear stress. Here we show that the power of the pressure correction is equal to the power of the irrotational shear stress. The viscous pressure correction on the interface can be expressed by a harmonic series. The principal mode of this series is matched to the velocity potential and its coefficient is explicitly determined. The other modes do not enter into the expression for the drag on bubbles and drops. They vanish in the case of free gravity waves.
A conceptual model of assessing teaching performance and intellectual development of teacher candidates: a pilot study in the US

A conceptual model was developed in an urban undergraduate education institution in the US to assess teaching performance and intellectual development levels of teacher candidates. Danielson's framework of teaching performance and Perry's pattern of intellectual and ethical development were used for developing a conceptual model. A pilot study was conducted to 282 urban teacher candidates based on the conceptual model to assess their teaching performance and the intellectual development levels. The results from Danielson's and Perry's rubrics showed that the higher students moved to in their teacher education program, the more proficient their teaching performance became and the higher intellectual and ethical development became. Within each of the teaching performance domains and of the intellectual patterns, individual competency patterns varied. This conceptual model may hold promise as a measure of assessing teacher candidates’ growth through their performance-based artifacts rather than through the t...
Feeding, energy processing rates and EGG production in painted lady butterflies

Volume and energy ingestion rates, meal sizes (intakes to satiation) and meal frequencies were measured for previously unfed adult painted lady butterflies ( Vanessa cardui L.) fed sucrose solutions or nectar from Lantana camera flowers in the laboratory. Volume and energy rates of crop emptying, assimilation efficiencies and mature egg production over 1 week were measured for V. cardui fed on sucrose solutions to assess mechanisms for and consequences of maximizing net meal energy. Viscosity reduced volume ingestion rates as sugar concentration increased, and 35–52.5 % (w/v) sucrose produced a maximum rate of energy gain from sucrose solutions. Ingestion rates were lower from Lantana flowers. Increasing Lantana nectar concentration from 33 to 70 % sucrose would produce about the same rate of energy gain for a meal. Virtually all ingested sugars were assimilated. Energy processing rates of 30 μl meals did not vary with sex, varied little with concentration and were 12–30 times the rate of energy use for maintenance. For females this may be due to the linear dependence of mature egg production on the amount of sugar ingested. Average meal timing compensated for variations in food concentration. Meals may be initiated before complete crop emptying, and this would increase the overall rates of energy processing, particularly for small meals. If Vanessa are not time-constrained while foraging, selecting concentrated nectars would decrease foraging frequency and increase the number of mature eggs produced after a meal.
Motivations for Adolescent Physical Activity

Background: Motivating adolescents to maintain levels of physical activity (PA) is important because regular PA in adolescence contributes to physical, psychological, and social well-being and PA during adolescence has been associated with activity levels in adulthood. Purpose: The overall aim of this study is to validate a measure of external reward, health values, and personal interest motivations for adolescent PA developed by Wold and Kannas and to examine the relationship between these motivations and level of PA. Methods: A nationally representative sample of 9011 adolescents completed the Health Behavior in School-aged Children survey instrument. Ten items were used to measure PA motivations. Multiple group confirmatory factor analysis and structural equation modeling were applied to test the 3-factor structure of the motivation scale and to examine the relationship between the 3 motivations and PA. Results: The Wold and Kannas’s motivation measure assessed external, social, and health motivations ...
Genetic Immunization of Wild-Type and Hepatitis C Virus Transgenic Mice Reveals a Hierarchy of Cellular Immune Response and Tolerance Induction against Hepatitis C Virus Structural Proteins

To study the effect of genetic immunization on transgenic expression of hepatitis C virus (HCV) proteins, we evaluated the immunological response of HCV transgenic mice to HCV expression plasmids. FVB/n transgenic mice expressing HCV structural proteins (core, E1, and E2) and wild-type (WT) FVB/n mice were immunized intramuscularly with plasmids expressing core (pHCVcore) or core/E1/E2 (pHCVSt). After immunization, HCV-specific humoral and cellular immune response was studied. Both WT and transgenic mice immunized with either HCV construct produced antibodies and exhibited T-cell proliferative responses against core or envelope. In WT mice immunized with pHCVSt, cytotoxic T-lymphocyte (CTL) activities were detected against E2 but not against core or E1, whereas strong CTL activities against core could be detected in WT mice immunized with pHCVcore. In pHCVSt-immunized, transgenic mice, CTL activities against the core or envelope were completely absent, but core-specific CTL activities could be detected in pHCVcore-immunized transgenic mice. A similar pattern of immune responses was also observed in other mouse strains, including a transgenic line expressing human HLA-A2.1 molecules (AAD mice). Despite the presence of a peripheral cellular immunity against HCV, no liver pathology or lymphocytic infiltrate was observed in these transgenic mice. Our study suggests a hierarchy of CTL response against the HCV structural proteins (E2 > core > E1) in vivo when the proteins are expressed as a polyprotein. The HCV transgenic mice can be induced by DNA immunization to generate anti-HCV antibodies and anticore CTLs. However, they are tolerant at the CTL level against the E2 protein despite DNA immunization.
The influence of a unilateral fixed ankle on metabolic and mechanical demands during walking in unimpaired young adults.

The plantarflexors provide a major source of propulsion during walking. When mechanical power generation from the plantarflexor muscles is limited, other joints may compensate to maintain a consistent walking velocity, but likely at increased metabolic cost. The purpose of this study was to determine how a unilateral reduction in ankle plantarflexor power influences the redistribution of mechanical power generation within and across limbs and the associated change in the metabolic cost of walking. Twelve unimpaired young adults walked with an ankle brace on the dominant limb at 1.2 m/s on a dual-belt instrumented treadmill. Lower extremity kinematics and kinetics as well as gas exchange data were collected in two conditions: (1) with the brace unlocked (FREE) and (2) with the brace locked (FIXED). The brace significantly reduced ankle plantarflexion excursion by 12.967 3.601 (po 0.001) and peak ankle mechanical power by 1.037 0.51 W/kg (po 0.001) in the FIXED versus FREE condition. Consequently, metabolic power (W/kg) of walking in the FIXED condition increased by 7.4% compared to the FREE condition (p ¼0.03). Increased bilateral hip mechanical power generation was observed in the FIXED condition (po0.001). These results suggest that walking with reduced ankle power increases metabolic demand due to the redistribution of mechanical power generation from highly efficient ankle muscle-tendons to less efficient hip muscle-tendons. A within and across limb redistribution of mechanical workload represents a potential mechanism for increased metabolic demand in pathological populations with plantarflexion deficits or those that walk with an ankle–foot orthosis that restricts range of motion. Published by Elsevier Ltd.
Enhancement of Two Motor Functions of the Lower Extremity in a Child With Spastic Quadriplegia

This single-subject experimental design examined the immediate effects of four neurodevelopmental treatment (NDT) activities on two dependent variables: dorsiflexor muscle activity during an equilibrium response and frequency of heel contact during movement to a standing position. The subject was a 2.5-year-old boy with spastic quadriplegia. During the seven days of Baseline 1 Phase, the nine days of Treatment Phase, and the seven days of Baseline 2 Phase, dorsiflexor muscle activity was examined using an EMG instrument with surface electrodes. Frequency of heel contact was recorded as the number of times in seven trials that the child came to a standing position with his heel contacting the floor. Conditions were identical across all three phases except that four NDT activities were introduced during the Treatment Phase and were withdrawn during the Baseline 2 Phase. The results demonstrated that these NDT activities increased dorsiflexor muscle activity during a posterior equilibrium reaction and increased the frequency of heel contact when the child came to a standing position. This study contributes to the growing body of literature in NDT.
A precision timing discriminator for high density detector systems

Most high-resolution time measurement techniques require discriminators that accurately mark the time arrival of events regardless of their intensity. Constant fraction discriminators or zero-crossing discriminators are generally used. Most are sensitive to the shape of event waveforms and may require cumbersome delay lines. The authors describe a zero crossing discriminator which accurately detects the maxima and minima of a measured waveform. Basically, it consists of a fast voltage comparator and a single integrating time constant, RC. A time walk of 100 ps in an amplitude range exceeding 100:1 has been achieved for waveforms from 1.5 ns to 15 ns full width at half maximum (FWHM). An arming level discriminator is added to eliminate triggering by noise. Easily implemented in either monolithic of hybrid technology, the circuit is suitable for large multichannel detector systems where size and power dissipation are crucial. Circuit diagrams and typical measured data are also presented. >
Does Income Inequality Lead to Consumption Inequality? Evidence and Theory

This paper first documents the evolution of the cross-sectional income and consumption distribution in the US in the past 25 years. Using data from the Consumer Expenditure Survey we find that a rising income inequality has not been accompanied by a corresponding rise in consumption inequality. Over the period from 1972 to 1998 the standard deviation of the log of after-tax labor income has increased by 20% while the standard deviation of log consumption has increased less than 2%. Furthermore income inequality has increased both between and within education groups while consumption inequality has increased between education groups but mildly declined within groups. We then argue that these empirical findings are consistent with the hypothesis that an increase in income volatility has been an important cause of the increase in income inequality, but at the same time has lead to an endogenous development of credit markets, allowing households to better smooth their consumption against idiosyncratic income fluctuations. We develop a consumption model in which the sharing of income risk is limited by imperfect enforcement of credit contracts and in which the development of financial markets depends on the volatility of the individual income process. This model is shown to be quantitatively consistent with the joint evolution of income and consumption inequality in US, while other commonly used consumption models are not.
Beat-to-beat determinants of the beat-to-beat temporal and spatial variability of repolarization.

Abstract Background The goal of this study was to compare the time series predictors of beat-to-beat variability in repolarization in healthy individuals. Methods Spatial QRS- and T-vector amplitudes, spatial QRS-T, RR′ and TT′ angles, RR′ and QT intervals, and QRS- and T-loop roundness were measured on 453 consecutive sinus beats in 168 healthy subjects (mean age 39.8 ± 15.6 years; 50% men; 93% white). Panel time-series regression models were adjusted by age, sex, and race. Appropriate time series of ECG metrics served as predictors and outcomes. Results Increase in T-loop roundness index by 0.1 was associated with 1.1° (95%CI 0.9–2.2; P = 0.048) increase in corresponding TT′ angle. One unit increase in a respiration index was associated with 4 ms (95%CI 0.6–7.0; P = 0.021) increase in QT interval. Conclusions Spatial TT′ angle and beat-to-beat variability in T-loop roundness represent intrinsic measures of repolarization variability. QT interval variability characterizes the effect of respiration and heart rate variability.
Implications and impact of prior authorization policy on vancomycin use at a tertiary pediatric teaching hospital.

BACKGROUND We evaluated the performance of two consecutive antimicrobial stewardship interventions on vancomycin use. METHODS Prospective audit with intervention and real time feedback to providers were implemented in April 2004. In February 2009, the institutional vancomycin policy was modified requiring preauthorization by the pediatric infectious diseases clinician on-call. Monthly vancomycin use was calculated as doses administered per 1000 patient-days. RESULTS After 5 years of prospective-audit vancomycin use declined from 378 doses administered/1000 patient-days to 208 doses administered/1000 patient-days (45%). Following the implementation of preauthorization, vancomycin use decreased by an additional 16% in the subsequent 4 years. When compared with the trend of vancomycin use with prospective-audit, the trend of vancomycin use after the implementation of the restriction policy increased by 3.9 doses per month (SE: 1.51, P=0.012) during the subsequent 51 months. CONCLUSIONS Implementation of preauthorization didn't significantly reduce the use of vancomycin beyond the accomplishments by prospective-audit and feedback by a team of an infectious disease pharmacist and physician.
Effect of Replacement Therapy on Dental Caries Experience of Radiothyroidectomized Rats.

SummaryThe activity of the thyroid gland appears to be directly related to the incidence of dental caries in the rat, for thyroxine injected significantly decreases the caries rate and radiothyroidectomy significantly increases it. The thyroid hormone appears to be primarily involved since the increased caries rate resulting from radiothyroidectomy is directly counteracted by the administration of thyroxine. Testosterone similarly appears to play a role in this mechanism, since the dental caries rate is also significantly reduced when it is injected into radiothyroidectomized animals even in the absence of thyroxine.
Liquid Chromatographic Determination of Gentamicin in Serum with Spectrophotometric Detection

A simple, accurate, and specific liquid chromatographic procedure is described for the determination of gentamicin in 50 muL of serum. Gentamicin and sisomicin (IS) were converted into their trinitrophenyl derivatives by reaction with a water soluble derivatizing agent at 70 degrees C for 30 minutes. The derivatives were extracted from the crude mixture with chloroform, which was separated, evaporated, and the residue reconstituted in acetonitrile. Gentamicin was separated into three major isomers (C1, C2, and C1a) on a reversed-phase octyl column by eluting with a mobile phase. The eluted compounds were detected at 340 nm and quantified from their peak heights or peak areas. Chromatography was complete in less than 11.0 minutes. The lower limit of detection for gentamicin was less than 0.5 mg/L, analytical recoveries varied from 96.6% to 99.3%, linearity extended to 15.0 mg/L, and day-to-day precision was between 2.2% to 2.9%.
Use of acellular dermal replacement in reconstruction of nonhealing lower extremity wounds

Dermal templates are well established in the treatment of burn wounds and acute nonburn wounds. However, the literature regarding their use for reconstruction of chronic, nonhealing wounds is limited. This study describes a series of patients with chronic wounds reconstructed with a commercially available bilayer, acellular dermal replacement (ADR) containing a collagen-glycosaminoglycan dermal template and a silicone outer layer. A retrospective review was performed of 10 patients treated for chronic wounds with ADR and negative pressure dressing followed by split-thickness skin graft between July 2006 and January 2009. Data collected included age, gender, comorbidities, medications, wound type or location, wound size, the number of applications of ADR, the amount of ADR applied (in square centimeter), the amount of time between ADR placement and grafting, complications, need for reoperation, and percentage of graft take after 5 and 14 days. The mean age of study subjects was 44 years. All patients in the study had comorbidities that interfere with wound healing and were treated for lower extremity wounds (four to legs, five to ankles, and one to foot). The wounds had a variety of causative factors including venostasis ulcers (6, 60%), trauma in diabetic patients (2, 20%), brown recluse bite (1, 10%), and a wound caused from purpura fulminans (1, 10%). The average wound size and amount of ADR applied was 162±182 cm². Each patient required only one application of ADR. The average time between ADR placement and skin grafting was 36.5 days. The mean percentage of graft take at 5 days was 89.55%, 14 days was 90%, and 21 days was 87.3%. Only two patients required regrafting, and one of these grafts was lost because of patient noncompliance. ADR can be used successfully in the treatment of chronic wounds. ADR provides direct wound coverage and can conform to a variety of anatomical sites. This study demonstrates that the use of ADR in treating chronic wounds results in high rates of skin graft take. Favorable results were obtained despite the majority of patients having comorbidities that would normally interfere with wound healing.
DeltaCon: Principled Massive-Graph Similarity Function with Attribution

How much has a network changed since yesterday? How different is the wiring of Bob’s brain (a left-handed male) and Alice’s brain (a right-handed female), and how is it different? Graph similarity with given node correspondence, i.e., the detection of changes in the connectivity of graphs, arises in numerous settings. In this work, we formally state the axioms and desired properties of the graph similarity functions, and evaluate when state-of-the-art methods fail to detect crucial connectivity changes in graphs. We propose DeltaCon, a principled, intuitive, and scalable algorithm that assesses the similarity between two graphs on the same nodes (e.g., employees of a company, customers of a mobile carrier). In conjunction, we propose DeltaCon-Attr, a related approach that enables attribution of change or dissimilarity to responsible nodes and edges. Experiments on various synthetic and real graphs showcase the advantages of our method over existing similarity measures. Finally, we employ DeltaCon and DeltaCon-Attr on real applications: (a) we classify people to groups of high and low creativity based on their brain connectivity graphs, (b) do temporal anomaly detection in the who-emails-whom Enron graph and find the top culprits for the changes in the temporal corporate email graph, and (c) recover pairs of test-retest large brain scans ( ∼17M edges, up to 90M edges) for 21 subjects.
Cholinergic regulation of mood and REM sleep: Potential model and marker of vulnerability to affective disorder

To test the hypothesis that depression and REM sleep share common cholinergic mechanisms the authors administered arecoline 25 min after completion of the first REM period to 14 patients with remitted bipolar affective disorder, 15 normal controls, and 5 subjects with a personal or family history of affective disorder. The second REM period occurred significantly sooner in the remitted patients than in the normal controls. The patients also had a significantly higher density of eye movements during the first REM period and a higher percentage of REM sleep. The authors believe that increased cholinergic sensitivity and REM density may be biological markers of increased vulnerability to bipolar affective illness.