cssi/SciSciGPT-SciSciNet huggingface dataset:
Pressure and flow in fluid films constrained between translating and vibrating flexible surfaces

Abstract In this paper, the dynamic pressure and flow developed in a two-dimensional, viscous fluid film constrained between flexible surfaces are analyzed. The problem formulation assumes that the response of the flexible surface is governed by linear equations of motion, and the fluid motion is governed by linearized momentum equations including the unsteady inertia. Three states of the model are developed to describe the coupled fluid-structural response problem. The fluid dynamic pressure is derived in the frequency domain as a function of the fluid impedances and the surface transverse vibrations. The perturbed, coupled problem is described by an integral equation (in state vector form) that governs the coupled responses of the flexible surfaces. The integral equation is solved by a discretization method. The analysis is applied to a rigid slider bearing with a flexible, translating plate surface under the excitation of a harmonic point load. The accuracy of the discretization method is evaluated, and numerical results for the dynamic pressure and the plate response are presented.
Desert springs‐both rare and endangered

1. Springs occur in all American deserts but their distribution is patchy and they are very difficult to locate. 2. Desert spring floras and faunas exhibit high diversity but many of the included species are undescribed or poorly known. 3. The conservation value of desert spring communities involves both their biodiversity and their research opportunities, both pure and applied. The communities offer real-life results that can help understand the effects of progressive habitat loss and degradation. Thus their study reflects strongly on problems concerning the development and management of natural parks and reserves. 4. Factors endangering desert spring systems include the misuse of the spring and/or its supporting aquifer, poor conservation practices and the introduction of exotic species.
Cross‐species Discrimination of Individual Odors by Hamsters (Muridae: Mesocricetus auratus, Phodopus campbelli)

Golden hamsters, Mesocricetus auratus, and Djungarian hamsters, Phodopus campbelli, Muridae, were tested for the ability to discriminate between individual odors from both their own species and the other species. Hamsters were tested using an habituation technique, in which differences in time spent investigating familiar and novel scents indicate discrimination of individual differences. Both species showed similar patterns of results when tested with flank gland scents from golden hamsters and ventral gland scents from Djungarian hamsters: The duration of investigation of samples from the same individual scent donor declined over trials, indicating recognition of this scent, but then increased when a scent from a novel individual was presented, indicating discrimination of individual differences. Thus, the capacity and tendency to respond differentially to signals from different individuals is not confined to a single species, suggesting the lack of species-specificity in the signals and perceptual mechanisms involved in individual recognition by scent. This capacity may be common in mammals, and if so suggests the possibility for considerable knowledge of heterospecific individuals.
A kinetic folding intermediate probed by native state hydrogen exchange.

Stopped-flow fluorescence studies on the N-terminal domain of rat CD2 (CD2.d1) have demonstrated that folding from the fully denatured state (U) proceeds via the transient accumulation of an apparent intermediate (I) in a so-called burst phase that precedes the rate-limiting transition leading to the native state (N). A previous pH-dependent equilibrium hydrogen exchange (HX) study identified a subset of amides in CD2.d1 which, under EX2 conditions, exchange from N with free energies greater than or equal to the free energy difference between the N and I states calculated from the stopped-flow data. Under EX1 conditions the rates of HX for these amides tend towards an asymptote that matches the global unfolding rate calculated from the stopped-flow data, suggesting that exchange for these amides requires traversing the N-to-I transition state barrier. Exchange for these amides presumably occurs from exchange-competent forms comprising the kinetic burst phase therefore. To explore this idea further, native state HX (NHX) data have been collected for CD2.d1 under EX2 conditions using denaturant concentrations which span either side of the denaturant concentration where, according to the stopped-flow data, the apparent U and I states are iso-energetic. The data fit to a two-component, sub-global (sg)/global (g) NHX mechanism, yielding ΔG and m value parameters (where the m value is a measure of hydrocarbon solvation). Regression analysis demonstrates that the (msg, ΔGsg) and (mg, ΔGg) values calculated for this subset of amides correspond with those describing the kinetic burst phase transition. This result confirms the ability of the NHX technique to explore the structural and energetic properties of kinetic folding intermediates.
Understanding the Impact of Proactive Personality on Job Performance: The Roles of Tenure and Self-Management

The current study investigated the moderating impact of job tenure and the mediating process of self-management on the relationship between proactive personality and performance. Using a sample of 95 sales executives, results indicated a significant interaction between proactive personality and job tenure. In addition, there was an indirect effect of self-management behavior on the relationship between proactive personality and performance. Such findings suggest that a proactive personality may be differentially related to performance dependent on job tenure and that self-managing behaviors may be a key linking mechanism between proactive personality and performance. Implications for both research and practice are discussed.
Elastic continua in high frequency excitation field

The response of elastic continua to high-frequency excitations is decomposed in two parts: 'slow' motion which practically remains unchanged during a vanishingly small period of time, and 'fast' motions whose mean value during this period is negligible but whose energy contribution is essential. After such a decomposition the 'slow' and 'fast' motions become non-linearly coupled by the corresponding governing equations. This coupling leads to an additional 'effective' potential energy which changes the 'mean' stiffness characteristics. The results can be used for dynamical stiffening of flexible structural elements, for a temporary increase of their stiffness in the course of occasional loads to prevent buckling or wrinkling.
Investigation of DNA‐Binding Properties of Organic Molecules Using Quantitative Structure‐Activity Relationship (QSAR) Models

Due to the great potential of DNA as a receptor, many classes of synthetic and naturally occurring molecules exert their anticancer activities through DNA-binding. In the field of antitumor DNA-binding agents, a number of acridine and anthracycline derivatives are in the market as chemotherapeutic agents. However, the clinical application of such classes of compounds has encountered problems such as multi-drug resistance and secondary and/or collateral effects. Thus, there has been increasing interest in discovering and developing small molecules that are capable of DNA-binding, which will be expected to be used either in place of or in conjunction with, the existing compounds. The interest in the application of the QSAR paradigm has steadily increased in recent decades and we hope it may be useful in the design and development of DNA-binding molecules as new anticancer agents. In the present review, an attempt has been made to understand the DNA-binding properties of different compound series and discussed using 27 QSAR models, which reveal a number of interesting points. The most important determinants for the activity in these models are Hammett electronic (sigma and sigma+), hydrophobic, molar refractivity, and Sterimol width parameters.
Surface science studies of model fuel cell electrocatalysts

The purpose of this review is to discuss progress in the understanding of electrocatalytic reactions through the study of model systems with surface spectroscopies. Pure metal single crystals and well-characterized bulk alloys have been used quite successfully as models for real (commercial) electrocatalysts. Given the sheer volume of all work in electrocatalysis that is on fuel cell reactions, we will focus on electrocatalysts for fuel cells. Since Pt is the model fuel cell electrocatalyst, we will focus entirely on studies of pure Pt and Pt bimetallic alloys. The electrode reactions discussed include hydrogen oxidation/evolution, oxygen reduction, and the electrooxidation of carbon monoxide, formic acid, and methanol. Surface spectroscopies emphasized are FTIR, STM/AFM and surface X-ray scattering (SXS). The discussion focuses on the relation between the energetics of adsorption of intermediates and the reaction pathway and kinetics, and how the energetics and kinetics relate to the extrinsic properties of the model system, e.g. surface structure and/or composition. Finally, we conclude by discussing the limitations that are reached by using pure metal single crystals and well-characterized bulk alloys as models for real catalysts, and suggest some directions for developing more realistic systems.
Interactive Slave Operations: Muslim-Christian Jewish Contracts in Thirteenth-Century Barcelona

Medieval Mediterranean Spain saw routine interaction between all three ethnoreligious populations, most of it random and undocumented. Slave purchases constituted one such tri-ethnic situation, as exemplified in the four charters transcribed and contextualized here, from the cathedral archives of Barcelona in 1252, 1275, 1286, and 1290. Each operation moved a slave from one public and private cultural ambience to another; each involved women; each was a local, short-term transaction; and each illustrates the generalities available in our slave data base. Family, social class, economic framework, and legal context can be clarified for each transaction in turn. As corsairs scoured the seas, especially for women slaves to service the century's new patrician life-style, a Muslim slave community populated perhaps 21 percent of Barcelona households, part of a mass population interchange between Islam and Christendom, facilitated by Jewish entrepreneurs whose Hebrew signatures are on each of these early and therefore rare slave parchments.
Movie-maps: An application of the optical videodisc to computer graphics

An interactive, dynamic map has been built using videodisc technology to engage the user in a simulated “drive” through an unfamiliar space. The driver, or map reader, is presented with either sparsely sampled sequences of images taken by single frame cameras that replicate actual imagery from a space, or with computer synthesized replicas of those images. The reader may control the speed, route, angle of view and mode of presentation of this information and may thus tour the area. In addition, he may access spatially stored ancillary data stored in the buildings or in locales in the environment. This basic map is being enhanced to provide topographic views, and to incorporate optical and electronic image processing to provide a more responsive, visually complete representation of an environment.
Three-Dimensional Echocardiography in Adult Patients: Comparison Between Transthoracic and Transesophageal Reconstructions

Abstract Background: Three-dimensional (3D) echocardiography is a relatively new technique typically implemented with transesophageal imaging with multiplane transducers. Objectives: The goals of this study were (1) to test the feasibility of 3D reconstruction with a new transthoracic multiplane transducer in adult subjects with excellent quality of 2-dimensional images and (2) to compare these reconstructions with those obtained in the same patients with the transesophageal approach. Methods: Transthoracic multiplane image acquisition was performed in 37 patients who were selected on the basis of the quality of their 2-dimensional images. In addition, transesophageal acquisition was also performed in 19 of 37 patients. Three-dimensional reconstruction of mitral and aortic valves was performed. Three-dimensional images were reviewed, and the visualization of various anatomic features was graded. Results: The reconstruction of 25 mitral valves and 16 aortic valves, normal and pathologic, was feasible and resulted in visualization of anatomic detail. Score indexes of all valvular characteristics studied were not significantly different when transthoracic and transesophageal reconstructions were compared. Conclusions: Transthoracic 3D echocardiography with a multiplane transducer in adult patients with good acoustic windows is feasible. This technique will allow easy noninvasive serial assessment of valvular pathophysiologic characteristics. (J Am Soc Echocardiogr 1999;12:1045-52.)
The complete nucleotide sequence of isolate BYMV-GDD of Bean yellow mosaic virus, and comparison to other potyviruses.

The complete nucleotide sequence of Bean yellow mosaic virus (BYMV) gladiolus isolate GDD was determined and compared to broad bean isolates BYMV-MB4 and BYMV-S. The BYMV-GDD genome (9528 nt) was more similar to BYMV-MB4 (9532 nt) than to BYMV-S (9547 nt), which has “atypical” symptom expression and host range. The greatest variability occurred in the 5′ untranslated region, P1 protein, and NIa-VPg protein, the N-terminal two thirds of HC-Pro, and the C-terminal one third of P3. Each of these regions has been correlated with symptom or host differences between isolates of other potyviruses, and may contribute to the “atypical” nature of BYMV-S.
Induction and suppression of cytochrome P450 1A by 3,3',4,4',5-pentachlorobiphenyl and its relationship to oxidative stress in the marine fish scup (Stenotomus chrysops).

The planar polychlorinated biphenyl (PCB) 3,3′,4,4′-tetrachlorobiphenyl (TCB) causes dose-dependent induction and post-transcriptional suppression of hepatic cytochrome P450 1A (CYP1A) in the marine teleost scup (Stenotomus chrysops). That suppression is linked to inhibition and oxidative inactivation of CYP1A by TCB. Other planar PCBs, including 3,3′,4,4′,5-pentachlorobiphenyl (PeCB), inactivate scup CYP1A in vitro leading us to hypothesize that PeCB also will suppress CYP1A in vivo. We examined induction and suppression of CYP1A by PeCB in scup, as related to oxidative stress. PeCB at a low dose (0.01 mg/kg) induced hepatic microsomal spectral P450 and CYP1A protein and catalytic activities (ethoxyresorufin o-deethylase (EROD) and methoxyresorufin o-demethylase (MROD)) over an 18 day period. A high dose (1 mg PeCB/kg) only minimally induced hepatic spectral P450 and CYP1A content, and EROD and MROD rates remained at control levels at all sampling times, while CYP1A mRNA expression was induced strongly (up to 35-fold) at both doses. High dose PeCB had minimal effects on content of P450A (a CYP3A protein), P450B (a CYP2B-like protein) and cytochrome b5 in scup liver, suggesting that the suppression was specific for CYP1A. High dose PeCB suppressed EROD but not CYP1A protein in the kidney but did not strongly suppress either CYP1A or EROD in the heart or gill. PeCB stimulated ROS production (oxidation of dihydroethidium) by liver microsomes from the low dose but not the high dose fish, and the rate of PeCB-stimulated ROS production was correlated with EROD activity (r2=0.641, P<0.0005). Oxidative stress, indicated by increased levels of catalase, glutathione peroxidase, glutathione reductase and superoxide dismutase activities, was stimulated in the liver by low dose but not high dose PeCB. The results support a hypothesis that many PHAH can inactivate teleost CYP1A in vivo, and that CYP1A is a source of ROS. However, there appears to be a complex balance between the effects of PeCB on the levels of active CYP1A, ROS release and oxidative stress.
Integral representation of the Coulomb Green function derived from the Sturmian expansion

We recast the Sturmian expansion of the one-particle Coulomb Green function as an integral which, through an appropriate choice of contour, is applicable anywhere on the Riemann energy surface (excluding the neighborhood of the negative real axis on the physical energy sheet, a region to which the series representation is ideally suited). As a numerical test we have used this integral representation, in conjunction with a two-particle convolution of one-particle Coulomb Green functions, to calculate the cross sections for both partial and complete breakup of the negative hydrogen ion by one-photon absorption.
Material Properties of Carbon-Infiltrated Carbon Nanotube-Templated Structures for Microfabrication of Compliant Mechanisms

Carbon nanotubes can be grown vertically from a substrate to form dense forests hundreds of microns tall. The space between the nanotubes can then be filled with carbon using chemical vapor deposition to create solid structures. These infiltrated structures can be detached from the substrate and operated as single-piece MEMS. To facilitate the design of compliant microdevices using this process, we explored the influence of two fabrication parameters—iron layer thickness and infiltration time—on the material’s mechanical properties, using the fracture strain to judge suitability for compliance. We prepared samples of a simple meso-scale cantilever beam pattern at various levels of these parameters, applied vertical loads to the tips of the beams, and recorded the forces and deflections at brittle failure. These data were then used in conjunction with a nonlinear FEA model of the beams to determine Young’s modulus and fracture stress for each experimental setting. From these data the fracture strains were obtained. The highest fracture strain observed was 2.48%, which is approximately 3.5 times that of polycrystalline silicon. This was obtained using an iron layer thickness of 10 nm and an infiltration time of 30 minutes. We used a test device—a compliant gripper mechanism for holding mammalian egg cells—to demonstrate the use of this material in compliant MEMS design.Copyright © 2011 by ASME
Implications for antimicrobial prescribing of strategies based on bacterial eradication

Antimicrobial prescribing in respiratory tract infection is generally empirical. Agents that do not eradicate the key bacterial respiratory pathogens (Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis) provide suboptimal therapy. A recent paper developed by a multidisciplinary, multinational group presented a consensus on the principles that should underpin appropriate antimicrobial prescribing. In summary, in order to ensure clinical success and minimize the threat of resistance, empirical therapy should avoid unnecessary and inappropriate use of antimicrobials, deliver the right agent at the right dose and duration, and rapidly eradicate the pathogen at the site of infection. Accurate diagnosis is essential to ensure that only bacterial infections are treated with antibacterial agents. The application of pharmacokinetic/pharmacodynamic (PK/PD) principles to both new and existing antimicrobials allows the prediction of bacteriologic efficacy. Applying these principles when prescribing therapy can help in reducing the potential for the selection and spread of resistance. Local resistance patterns and the bacteriologic/clinical impact of resistance should also be considered. The use of antimicrobials with optimal PK/PD characteristics may be more cost-effective than allowing the possibility of resistance-induced failure. Changing prescribing habits without taking all these factors into account may increase the incidence of unfavorable patient outcomes and the cost of treatment, with more referrals and hospitalizations. Changes in prescribing habits should be considered carefully, to avoid unintended negative consequences. It is the responsibility of physicians to ensure that each prescription is necessary and will maximize the potential for clinical cure, but there is also a collective responsibility to sustain the diversity of antimicrobial therapy via appropriate formularies, guidelines and licensing, reduced over-the-counter availability, and continued research and development through academia and industry. To maximize clinical cure and minimize the emergence and spread of resistance, antimicrobial prescribing should maximize bacterial eradication, and clinical drug evaluation needs to be brought into line with this need.
Track count estimator for DVD and CDROM

An estimator is shown to accurately count tracks during a seek in a DVD or CDROM storage device. The estimator states are position and velocity. Although the gains can be adapted via the recursive Kalman equations, the track count accuracy suffers little degradation if the gains are fixed. The position estimate's bandwidth can be matched to the seek system poles affording optimum filtering. Although the input is a nonlinear function of position, the estimator is constructed in such a way as to maintain linearity.
Air cell gas tensions of the chick embryo at sea level and altitude: the contribution of Aggazzotti, 1914.

Abstract This historical note draws attention to the forgotten but remakable study of A. Aggazzotti of Italy who in 1914 described for the first time the changes in O2 and CO2 tensions during the course of development of the chick embryo and repeated these observations at an altitude of 3000 m. When his gas tension data are recalculated and compared with those obtained by Wangensteen et al. at sea level and altitude, 60 years later, the agreement is good.
Multiple mitochondrial DNA deletions in sporadic inclusion body myositis : A study of 56 patients

Inclusion body myositis, a chronic inflammatory disorder, is the most common cause of myopathy in adults over the age of 50. Diagnosis is based on clinical features and distinctive morphological findings by both light and electron microscopy. The causes of inclusion body myositis are still unknown. Ultrastructural mitochondrial changes and ragged-red fibers are common in patients with sporadic inclusion body myositis, and multiple [correction of mutiple] mitochondrial DNA (mtDNA) deletions have been reported in 3 such patients, suggesting that mtDNA mutations may have a pathogenetic role. We studied 56 patients with sporadic inclusion body myositis, using a combination of clinical, morphological, biochemical, and molecular genetic analyses to determine the frequency and the distribution of mtDNA deletions. Using the polymerase chain reaction, we found multiple mtDNA deletions in 73% of patients, compared to 40% of normal age-matched control subjects and 47% of disease control subjects. The presence of deletions correlated with morphological evidence of ragged-red, cytochrome c oxidase-negative fibers, and with defects of complexes I and IV of the electron transport chain. Although aging may account for a proportion of mtDNA deletions in patients with sporadic inclusion body myositis and control subjects, mtDNA alterations may be accelerated in sporadic inclusion body myositis.
Perturbative treatment of Pauli antisymmetrization of quarks in a nucleon gas

Abstract A soluble model based on a Slater determinantal wave function is used to study the Neumann and Fredholm perturbative series for treating Pauli exchange effects for a finite number of fermions. The usefulness of Pade approximants and a linked-cluster (LC) diagrammatic expansion are shown. A Neumann LC diagrammatic expansion in powers of the quark exchange operator between nucleons is constructed for a nonrelativistic quark model of the nucleon Fermi gas. LC diagrams involving up to four nucleons are calculated for the wave function overlap, the kinetic energy, and the nucleon size. Four-nucleon contributions are shown to be necessary for k p a ⩾ 1.0, where k p is the Fermi momentum and a is the nucleon r.m.s. radius. For large nucleons, the calculated Pauli corrections in normal nuclear matter have signs opposite to those in S-wave nuclei.
Multiple immunizations with adenovirus and MVA vectors improve CD8+ T cell functionality and mucosal homing

Abstract Recombinant adenovirus vectors and MVA vectors were used in prime boost vaccine regimens to address the impact of repeated immunizations on transgene product-specific CD8+ T cell frequencies, phenotypes, function, and localization. We show that a regimen with three immunizations incorporating MVA, human adenovirus serotype 5 and chimpanzee-derived adenoviruses serotype 68 or 7 yields high transgene product-specific CD8+ T cell frequencies in spleen, blood, lymph nodes, and peritoneal lavage. Furthermore, upon triple immunization increased frequencies of transgene-specific T cells were measured at mucosal sites such as mesenteric lymph nodes, intestinal epithelium, and Peyer's patches. Multiple dose vaccine regimens that markedly increase functionally active transgene-specific T cells and target them to the appropriate ports of entry may be important in protection against pathogens such as HIV-1.
A GENERALIZED FRACTIONALLY INTEGRATED AUTOREGRESSIVE MOVING-AVERAGE PROCESS

. This paper considers the long memory Gegenbauer autoregressive movingaverage (GARMA) process that generalizes the fractionally integrated ARMA (ARFIMA) process to allow for hyperbolic and sinusoidal decay in autocorrelations. We propose the conditional sum of squares method for estimation (which is asymptotically equivalent to the maximum likelihood estimation) and develop the asymptotic theory. Many results are in sharp contrast to those of the ARFIMA model. Simulations are conducted to assess the performance of the proposed estimators in small sample applications. Two applications to the sunspot data and the US inflation rates based on the wholesale price index are provided.
Keratin 16–Null Mice Develop Palmoplantar Keratoderma, a Hallmark Feature of Pachyonychia Congenita and Related Disorders

Keratin 16 (KRT16 in human, Krt16 in mouse), a type I intermediate filament protein, is constitutively expressed in epithelial appendages and is induced in the epidermis upon wounding and other stressors. Mutations altering the coding sequence of KRT16 cause pachyonychia congenita (PC), a rare autosomal dominant disorder characterized by hypertrophic nail dystrophy, oral leukokeratosis, and palmoplantar keratoderma (PPK). PPK associated with PC is extremely painful and compromises patient mobility, making it the most debilitating PC symptom. In this study, we show that, although inherited in a recessive manner, the inactivation of Krt16 in mice consistently causes oral lesions as well as PPK-like hyperkeratotic calluses on Krt16−/− front and hind paws, which severely compromise the animals' ability to walk. Our findings call into question the view that PC-related PPK arises exclusively as a gain-of-function on account of dominantly acting mutated keratins, and highlight the key role of modifiers in the clinical heterogeneity of PC symptoms.
Using cooperative learning and classroom research with culturally diverse students

To better meet the needs of inexperienced adult learners from a diversity of cultures, this community college combined elements of cooperative learning with Classroom Research.
Re/Production of science process skills and a scientific ethos in an early childhood classroom

Many educators and researchers are convinced that age limits what students can learn and achieve in science. Elementary school curricula focus on isolated process skills under the faulty assumption that young students are not capable of combining the process skills and content knowledge necessary for reasoning scientifically. In the present study, I demonstrate that many process skills are produced in conversations between second grade students and between these students and their teachers, including: questioning, hypothesis formation, experimental design, identifying relevant evidence, critical analysis of hypotheses and predictions, hypothesis reconstruction, and variable identification. Through conversation analysis I show that most classroom community members adopted the role of skeptic at some time, but there was a strong tendency to defer to authoritative sources when resolving debates. This latter observation led to further investigation of when and how authoritative sources were consulted and used, and when and how a skeptical stance was taken. I show that, as students used science process skills and interacted with each other and teacher-mediators, community practices, values, and mores were shaped and an ethos of science began to emerge. It is my contention that this ethos often emerges unconsciously as part of the community’s dynamic set of rules and schema. Teachers who are attuned to the tension between open-mindedness and skepticism, and how they and their students cope with this dialectic, however, can actively shape the scientific ethos of their classroom community.
The NICMOS observational program: some personal examples

Abstract This paper reviews a few of the author's observational programs with the Near Infrared Camera and Multi-Object Spectrometer on the Hubble Space Telescope. These programs are taken as being partially representative of the very large body of observations carried out by NICMOS in both General Observer and Guaranteed Time Observer scientific programs.
Looking in on the Children: Using Developmental Psychology as a Tool for Hypothesis Testing and Model Building in Social Psychology

The aim of this article is to illustrate how developmental psychology may be used as a tool for hypothesis testing and model building in social psychology. To this end, 5 conceptual themes and I methodological theme linking developmental psychology to social psychology are outlined. Emphasis is put on the potential of each theme to provide insight into the processes underlying the phenomena studied by social psychologists. Examples of how the themes have been used in the past or might be used in the future to inform hypothesis testing and model building in specific areas are provided.
The effect of pregnancy and stress on the onset of placentophagia in Long-Evans rats.

Abstract Most virgin rats do not eat placenta when it is presented to them; virtually all parturient rats do. This study was designed to examine the role of the duration and termination of pregnancy on the induction of placentophagia. Time-bred rats determined by a pretest not to be attracted to placenta (nonplacentophages), were tested for placentophagia on one of a number of days of pregnancy. A comparable group was tested for placentophagia after surgical termination of pregnancy on Day 21. Groups of virgins were run controlling for the time interval between the pretest and the placentophagia test, and for a time interval that included a “stressful” event. The results were that (a) the incidence of placentophagia rose gradually from Day 7 to Day 15 of pregnancy, then remained stable, at about 0.4, until delivery; (b) pregnancy termination did not produce an effect on placentophagia greater than that of unterminated pregnancy; (c) a pretest-test interval containing a “stressful” event produced significantly more placentophagia than one that did not contain such an event; and (d) the maximum level of placentophagia observed during pregnancy was the same as that produced in virgins by a “stressful” event.
Determination of organomercury compounds in aqueous samples by capillary gas chromatography-atomic fluorescence spectrometry following solid-phase extraction

A new method based on capillary gas chromatography-atomic fluorescence spectrometry (GC/AFS) is described for the determination of methylmercury (MeHg) and ethylmercury (EtHg) in water samples. An improved sample preparation methodology was developed, which involves preconcentration of the alkylmercury species from water samples, drawn with a 12 channel peristaltic pump, onto sulfhydryl cotton fiber (SCF) adsorbent packed in a screening column, elution of MeHg and EtHg with a mixture of acidic potassium bromide and copper sulfate solution, and back-extraction using methylene chloride. Analysis was performed by capillary GC/AFS with a DB-1 column. Some important parameters, including sample pH, presence of anions and cations, concentration of dissolved organic carbon (DOC), eluent type, and eluent volume were evaluated. With AFS as a detector, the capillary gas Chromatographic technique provides high selectivity, high sensitivity, and a straightforward method for organomercury halide analysis. It eliminates possible spectral interferences to the detector from other sample components and from chemicals used in the sample preparation procedure. The detection limit was 0.01 ng l−1 in a 11 water sample for both MeHg and EtHg. The result for organomercury analysis in a number of natural water samples is shown to illustrate the applicability of this method to real environmental samples.
The widowhood effect: a comparison of Jews and Catholics.

Using mortality data derived from tombstones in two Midwestern cemeteries, we compared the “widowhood effect” (decreased survival following the death of a spouse) among Jews and Catholics. Jewish men and women were both more likely to die sooner after the death of their spouses compared to Catholic men and women. Life table survival analysis indicated that the median number of years of survival following widowhood for Catholic and Jewish men were 7.7 years and 5.0 years, respectively (p < .01). For Catholic and Jewish women, it was 11.0 and 9.5 years, respectively (p < .01) Interpretations were offered in terms of Bowlby's attachment theory.
GIAO studies of magnetic shielding in FHF- and HF

Abstract Proton and fluorine magnetic shielding tensors are calculated for FHF - and HF using coupled Hartree-Fock (CHF) theory with gauge-invariant atomic orbitals (GIAO). The theoretical value of the hydrogen bond shift in FHF - determined from slightly extended basis set studies is in good agreement with experimental results. Thus a recent suggestion that the GIAO CHF approach will suffer from the same deficiencies as the ordinary CHF method for the FHF - ion does not appear to be correct.
Ray and wave optics modeling of laboratory x-ray lasers

Much progress has been made recently in characterizing the emission from neon- like Yttrium exploding foil x-ray lasers. Concomitant with that effort, we have carried out detailed modeling to enhance our understanding of the experiments and improve their design. Our modeling includes target hydrodynamics, calculation of gain, and both ray and wave optics propagation. We will describe our modeling of Yt x-ray lasers, including first simulations using a two transverse dimensional gain calculation. Our calculations indicate that the time-integrated signal is very sensitive to the time history of the gain, because of the rapid sweep of the beam in angle measured with respect to the plane of the foil.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Properties of Ca2+-, Mg2+-activated adenosine triphosphatase from rat incisor pulp

Abstract A plasma membrane fraction was prepared from pulps of freshly extracted incisors of rats using differential centrifugation at 35,000 g . Adenosine triphosphatase (ATPase) activity was measured by the release of inorganic phosphate from ATP. Assays were conducted at 37 °C for 30 min with 20 mM tris-HCl buffer plus 70 mM NaCl. Properties of the enzyme were as follows: pH optimum between 7.9–8.1; Ca 2+ or Mg 2+ alone activated the enzyme, with maximal activity at a divalent cation concentration of 5 mM; the enzyme was preferentially activated by Ca 2+ at low concentrations ( mM ) and by Mg 2+ at high concentrations (0.5 to 5.0mM); activity increased progressively up to 50 °C, and complete inactivation occurred at 70 °C; ATP, GTP and UTP were hydrolyzed at similar rates, while ADP and AMP were much less effective substrates; ouabain, tetracycline and fluoride in the dosages used did not inhibit ATPase activity.
ON POINT MULTISERIAL CORRELATION1

We present a simple form for the estimator of the point multiserial correlation coefficient between a quantitative variate X and a qualitative variate 7. Given a bivariate sample grouped in the form of an r×c contingency table the estimator is based on finding the optimum Y-scores which maximize the correlation coefficient. The resulting estimator is equivalent to Das Gupta's (1960) for ungrouped X-values, with the advantage of simplicity in its calculation. Under the assumption of conditional normality, the significance of point multiserial correlation may be studied by an F-test.
cAMP-dependent insulin modulation of synaptic inhibition in neurons of the dorsal motor nucleus of the vagus is altered in diabetic mice

Pathologies in which insulin is dysregulated, including diabetes, can disrupt central vagal circuitry, leading to gastrointestinal and other autonomic dysfunction. Insulin affects whole body metabolism through central mechanisms and is transported into the brain stem dorsal motor nucleus of the vagus (DMV) and nucleus tractus solitarius (NTS), which mediate parasympathetic visceral regulation. The NTS receives viscerosensory vagal input and projects heavily to the DMV, which supplies parasympathetic vagal motor output. Normally, insulin inhibits synaptic excitation of DMV neurons, with no effect on synaptic inhibition. Modulation of synaptic inhibition in DMV, however, is often sensitive to cAMP-dependent mechanisms. We hypothesized that an effect of insulin on GABAergic synaptic transmission may be uncovered by elevating resting cAMP levels in GABAergic terminals. We used whole cell patch-clamp recordings in brain stem slices from control and diabetic mice to identify insulin effects on inhibitory neurotransmission in the DMV in the presence of forskolin to elevate cAMP levels. In the presence of forskolin, insulin decreased the frequency of inhibitory postsynaptic currents (IPSCs) and the paired-pulse ratio of evoked IPSCs in DMV neurons from control mice. This effect was blocked by brefeldin-A, a Golgi-disrupting agent, or indinavir, a GLUT4 blocker, indicating that protein trafficking and glucose transport were involved. In streptozotocin-treated, diabetic mice, insulin did not affect IPSCs in DMV neurons in the presence of forskolin. Results suggest an impairment of cAMP-induced insulin effects on GABA release in the DMV, which likely involves disrupted protein trafficking in diabetic mice. These findings provide insight into mechanisms underlying vagal dysregulation associated with diabetes.
Modeling nitrate-nitrogen removal process in first-flush reactor for stormwater treatment.

Stormwater runoff is one of the most common non-point sources of water pollution to rivers, lakes, estuaries, and coastal beaches. While most pollutants and nutrients, including nitrate-nitrogen, in stormwater are discharged into receiving waters during the first-flush period, no existing best management practices (BMPs) are specifically designed to capture and treat the first-flush portion of urban stormwater runoff. This paper presents a novel BMP device for highway and urban stormwater treatment with emphasis on numerical modeling of the new BMP, called first-flush reactor (FFR). A new model, called VART-DN model, for simulation of denitrification process in the designed first-flush reactor was developed using the variable residence time (VART) model. The VART-DN model is capable of simulating various processes and mechanisms responsible for denitrification in the FFR. Based on sensitivity analysis results of model parameters, the denitrification process is sensitive to the temperature correction factor (b), maximum nitrate-nitrogen decay rate (Kmax), actual varying residence time (Tv), the constant decay rate of denitrifiying bacteria (vdec), temperature (T), biomass inhibition constant (Kb), maximum growth rate of denitrifiying bacteria (vmax), denitrifying bacteria concentration (X), longitudinal dispersion coefficient (Ks), and half-saturation constant of dissolved carbon for biomass (KCar-X); a 10% increase in the model parameter values causes a change in model root mean square error (RMSE) of −28.02, −16.16, −12.35, 11.44, −9.68, 10.61, −16.30, −9.27, 6.58 and 3.89%, respectively. The VART-DN model was tested using the data from laboratory experiments conducted using highway stormwater and secondary wastewater. Model results for the denitrification process of highway stormwater showed a good agreement with observed data and the simulation error was less than 9.0%. The RMSE and the coefficient of determination for simulating denitrification process of wastewater were 0.5167 and 0.6912, respectively, demonstrating the efficacy of the VART-DN model.
A comparison of mixed-effects quantile stratification propensity adjustment strategies for longitudinal treatment effectiveness analyses of continuous outcomes

The propensity adjustment is used to reduce bias in treatment effectiveness estimates from observational data. We show here that a mixed-effects implementation of the propensity adjustment can reduce bias in longitudinal studies of non-equivalent comparison groups. The strategy examined here involves two stages. Initially, a mixed-effects ordinal logistic regression model of propensity for treatment intensity includes variables that differentiate subjects who receive various doses of time-varying treatments. Second, a mixed-effects linear regression model compares the effectiveness of those ordinal doses on a continuous outcome over time. Here, a simulation study compares bias reduction that is achieved by implementing this propensity adjustment through various forms of stratification. The simulations demonstrate that bias decreased monotonically as the number of quantiles used for stratification increased from two to five. This was particularly pronounced with stronger effects of the confounding variables. The quartile and quintile strategies typically removed in excess of 80-90 per cent of the bias detected in unadjusted models; whereas a median-split approach removed from 20 to 45 per cent of bias. The approach is illustrated in an evaluation of the effectiveness of somatic treatments for major depression in a longitudinal, observational study of affective disorders.
A probabilistic power-aware routing algorithm for wireless ad-hoc networks

We propose a probabilistic routing algorithm for wireless ad-hoc networks. The focus is on applications that can tolerate end-to-end delays and those for which the final destination for the packets is a small region. The nodes are assumed stationary and establish connections with a master node according to a priority scheme that relates to their distances from the master node. Simulation results illustrate the performance of the proposed algorithm.
Compositional Ordering in GalnP for Heterostructure Formation

Compositional ordering is observed in essentially all III/V semiconductor alloys. The mechanism leading to the specific ordered structures formed is only now beginning to be understood. It is intimately related to the atomic-scale physical processes occurring on the surface during epitaxial growth, specifically surface reconstruction and the attachment of atoms at steps. This paper will emphasize the use of surface analytic techniques to better understand the ordering processes during organometallic vapor phase epitaxial growth of GaInP. Surface photo absorption has been used to determine, for the first time, that the surface reconstruction is (2×4)-like during growth of GaInP with Cu-Pt ordering. By increasing the growth temperature and/or decreasing the V/III ratio the concentration of phosphorus dimers characteristic of the (2×4) structure is observed to decrease in tandem with a decrease in the degree of order measured in the epitaxial layers. This suggests that formation of the (2×4) reconstruction is necessary for formation of the Cu-Pt ordered structure. Atomic force microscopy was used to examine the step structure. For exactly (001)-oriented substrates, growth at low V/III ratios produces islands surrounded by single monolayer steps. Increasing the V/III ratio leads to the formation of bilayer steps approximately 6 A high. A similar change in the structure of steps is observed in the vicinal regions for substrates misoriented to produce [110] steps. This phenomenon is interpreted in terms of the stabilization, at high V/III ratios, of the (2×2) reconstruction on the (111)B regions of the bilayer steps. This may also have an effect on formation of the Cu-Pt ordered structure. By changing the substrate temperature or the input partial pressure of the phosphorus precursor, the degree of order and, hence, the bandgap energy of GaInP, can be modulated during growth. This has allowed the production of a variety of single and double heterostructures. The heterostructures produced by changing the temperature from 740 to 620°C and from 620 to 520°C are abrupt. The heterostructures formed by changing the phosphine flow rate are not. The ordered structure in the lower layer persists into the upper layer. This may be an indication of the importance of the step structure.
Quality-of-life considerations in elderly patients with bladder cancer

Urothelial cell carcinoma primarily affects the elderly and may be associated with high morbidity and mortality. With the aging of the US population, therapeutic options for bladder cancer need to take into account the unique challenges of elderly patients who often have multiple associated comorbid conditions. Quality of life is now a well-recognized and important outcome measure that should be considered when deciding between the various treatments for bladder cancer. This is especially critical in the elderly patient where lengthening survival may not be the foremost goal. Treatments for both superficial and invasive bladder cancer may have an impact on quality of life, but a lack of baseline assessments in studies limits the conclusions that can be drawn. Based on available literature, quality of life in elderly patients undergoing radical cystectomy is satisfactory, regardless of whether a continent or incontinent form of urinary diversion is performed. Future prospective studies utilizing baseline a...
Interruption of pacemaker signals by a diencephalic nucleus in the African electric fish, Gymnarchus niloticus

The African electric fish Gymnarchus niloticus rhythmically emits electric organ discharges (EODs) for communication and navigation. The EODs are generated by the electric organ in the tail in response to the command signals from the medullary pacemaker complex, which consists of a pacemaker nucleus (PN), two lateral relay nuclei (LRN) and a medial relay nucleus (MRN). The premotor structure and its modulatory influences on the pacemaker complex have been investigated in this paper. A bilateral prepacemaker nucleus (PPn) was found in the area of the dorsal posterior nucleus (DP) of the thalamus by retrograde labeling from the PN. No retrogradely labeled neurons outside the pacemaker complex were found after tracer injection into the LRN or MRN. Accordingly, anterogradely labeled terminal fibers from PPn neurons were found only in the PN. Iontophoresis of l-glutamate into the region of the PPn induced EOD interruptions. Despite the exclusive projection of the PPn neurons to the PN, extracellular and intracellular recordings showed that PN neurons continue their firing while MRN neurons ceased their firing during EOD interruption. This mode of EOD interruption differs from those found in any other weakly electric fishes in which EOD cessation mechanisms have been known.