cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of Pressure on Plastic Deformation of Polycrystalline Solids: Some Geological Applications

Experimental studies on the effects of pressure on plastic properties are reviewed with an emphasis on those on geological materials. High pressures may affect plastic properties through two different ways: (i) through the effects of pressure on plastic deformation of a material with a given crystal structure and (ii) through the effects of pressure-induced phase transformations on plastic deformation. It is emphasized that the manner in which pressure affects plastic properties of solids depends on the microscopic mechanisms of plastic deformation and therefore it is essential to identify the mechanisms of deformation involved in a particular experimental condition. Three mechanisms are considered: (i) the Peierls mechanism, (ii) dislocation creep (power-law creep) and (iii) diffusion creep (or superplasticity). Creep strength of materials changes with pressure through the change in shear modulus and in the activation enthalpy for the Peierls mechanism. Structural phase transformations can dramatically change the creep strength determined by the Peierls mechanism. Changes can be either positive (increase in strength in a high pressure phase) or negative (decrease in strength in a high pressure phase). Creep strength controlled by dislocation creep usually increases exponentially with pressure through the increase in the activation enthalpy with pressure. Phase transformations can change the creep strength either positively or negatively for this mechanism depending on the manner in which dislocation mobility changes with crystal structure. Creep strength corresponding to diffusion creep changes with pressure in a similar fashion as dislocation creep. p] High pressures in the deep interior of Earth and other terrestrial planets could lead to a significant increase in viscosity with depth, resulting in high temperatures due to the feedback between viscosity and temperature. Also phase transformations in constituent minerals that occur in certain depth ranges can cause dramatic changes in plastic properties. Both of them are likely to have important influence on the style of convection in the mantle of terrestrial planets and thus affect their geological history and tectonic activities.
The McMansionization of America? Income stratification and the standard of living in housing, 1960–2000

Abstract Consumption patterns and living standards are relatively neglected in stratification research even though they are important indicators of material well-being. Consumption inequality is related to income and wealth disparities through complex processes not yet well understood. This paper addresses this gap by analyzing a striking shift in the standard of living in housing in the US that occurred at the same time as a substantial increase in income inequality. Houses became significantly bigger in the 1980s and 1990s just as inequalities deepened, reversing an earlier trend towards smaller houses. Diverse theoretical traditions in the consumption and housing stratification literatures explain this shift differently, and in particular posit very different effects of rising income inequality. I derive several alternative expectations from these traditions: two predicting that the increasing size of houses was broadly shared across income levels, while another expects it represented increasing divergence in living standards, paralleling the trend in income inequality. I use US Census and American Housing Survey data and several different methods to adjudicate between these theories. The results provide some support for each of the alternative expectations, but the most significant finding is that big house ownership became more concentrated among the affluent. A focus on living standards thus uncovers a key source of rising disparities at the turn of the 21st century with important implications for wealth stratification too since houses are the major debt and asset held by most Americans.
Potential impact of trauma on the ability to prevent depression among low-income mothers.

Background Violent trauma is common in urban communities. We explored the hypothesis that past trauma could moderate the effect of a cognitive behavioral intervention designed to prevent depression among urban, low-income mothers.
Epidemiological-environmental study of diesel bus garage workers: Chronic effects of diesel exhaust on the respiratory system

Two hundred and eighty-three (283) male diesel bus garage workers from four garages in two cities were examined to determine if there was excess chronic respiratory morbidity related to diesel exposure. The dependent variables were respiratory symptoms, radiographic interpretation for pneumoconiosis, and pulmonary function (FVC, FEV1, and flow rates). Independent variables included race, age, smoking, drinking, height, and tenure (as surrogate measure of exposure). Exposure-effect relationships within the study population showed no detectable associations of symptoms with tenure. There was an apparent association of pulmonary function and tenure. Seven workers (2.5%) had category 1 pneumoconiosis (three rounded opacities, two irregular opacities, and one with both rounded and irregular). The study population was also compared to a nonexposed blue-collar population. After indirect adjustment for age, race, and smoking, the study population had elevated prevalences of cough, phlegm, and wheezing, but there was no association with tenure. Dyspnea showed a dose-response trend but no apparent increase in prevalence. Mean percent predicted pulmonary function of the study population was greater than 100%, i.e., elevated above the comparison population. These data show there is an apparent effect of diesel exhaust on pulmonary function but not chest radiographs. Respiratory symptoms are high compared to blue-collarmore » workers, but there is no relationship with tenure.« less
Further results on skew-prime matrices for linear systems over rings

Skew-prime matrices over noncommutative rings and over the ring of rationals (over a field) are considered. For the first case, a simple proof of a relationship between certain matrices which plays a key role in output regulation/tracking problems is given. For the second case, over rationals, an approach towards a characterization of the "fixed poles" of this equation is developed.
Intravascular metabolism of an artificial transporter of triacylglycerols. Alterations of serum lipoproteins resulting from total parenteral nutrition with Intralipid.

Abstract As a model for transport in the bloodstream of exogenous triacylglycerols, we have studied the intravascular metabolism of Intralipid, an artificial, cholesterol- and protein-free ‘chylomicron’. Two patients with Crohn's disease and one patient with intermittent abdominal pain received total parenteral nutrition including between 50 and 100 g of Intralipid per day. Samples of serum were analyzed chemically for lipids, assayed for lecithin:cholesterol acyltransferase (EC 2.3.1.43), and analyzed by isopycnic density-gradient ultracentrifugation and electron microscopy. After 3 weeks of infusion, single-bilayer vesicles, 300–600 A in diameter, were present in the serum of each patient. Comprising equimolar amounts of phospholipids and unesterified cholesterol, and approximately 5% by weight of protein, these vesicles accumulated to levels of approximately 100, 300 and 50 mg/dl for the three patients indicated above, causing hyperlipidemia in the first two cases. In conjunction, the levels of HDL and lecithin:cholesterol acyltransferase had decreased by 40% in each patient. Upon stopping the infusions, vesicles disappeared with monophasic kinetics with a half-life of 2 days, and were not converted to HDL or other lipoproteins; HDL and lecithin: cholesterol acyltransferase returned to normal levels after a lag period of at least 4 days. Two normal subjects were studied during and after a single 4-h infusion of 50 g of Intralipid. Triacylglycerols were cleared with a half-life of 1 h, but at least 40% of the phospholipids remained in the serum as vesicles. Although Intralipid contains no steroids, unesterified cholesterol progressively entered the serum after the vesicles appeared. During these short-term studies, the levels of HDL and lecithin:cholesterol acyltransferase did not change. The observations indicate that vesicles, derived from a variable fraction of the Intralipid phospholipids, extract unesterified cholesterol into plasma. Inert and slowly cleared, the resulting mixed vesicles accumulate in the blood. The levels of HDL and lecithin:cholesterol acyltransferase decrease only when the intestine is bypassed for long periods of time, probably because the lipoprotein and enzyme are synthesized more slowly than usual. Our results suggest that in chylomicrons other mechanisms prevent phospholipids from being released into the bloodstream as vesicles.
Imaging of ependymomas: MRI and CT

The imaging features of intracranial and spinal ependymoma are reviewed with an emphasis on conventional magnetic resonance imaging (MRI), perfusion MRI and proton magnetic resonance spectroscopy, and computed tomography. Imaging manifestations of leptomeningeal dissemination of disease are described. Finally, salient imaging features obtained in the postoperative period to evaluate completeness of surgical resection, and thereafter for long-term surveillance for disease recurrence, are reviewed.
First-principles computational study of defect clustering in solid solutions of ThO2 with trivalent oxides

The energetics of mixing and defect ordering in solid solutions of fluorite-structured ${\text{ThO}}_{2}$ with oxides of trivalent cations (Sc, In, Y, Nd, and La) are investigated by electronic density-functional theory (DFT). Through DFT calculations of structures enumerated by lattice-algebra techniques, we identify the lowest energy patterns for defect clustering for four separate dopant concentrations. The most stable structures are characterized by a repulsive interaction between nearest-neighbor vacancies on the oxygen sublattice. The enthalpies of formation with respect to constituent oxides are positive for all dopants considered, and show a tendency to decrease in magnitude as the size and electronegativity of the trivalent dopant decrease. Due to the small positive formation enthalpies and low oxygen-vacancy binding energy with La dopants, ${\text{La}}_{2}{\text{O}}_{3}{\text{-ThO}}_{2}$ solid solutions are predicted to have relatively high ionic conductivities relative to those for the other aliovalent dopants considered. Our results are compared with those for the more widely studied ${\text{ZrO}}_{2}$ and ${\text{CeO}}_{2}$ fluorite-structured solid solutions with trivalent cations.
Gut Feeling in AKI: The Long Arm of Short–Chain Fatty Acids

In 1907, Elie Metchnikoff hypothesized that “autointoxication” by “putrefactive” bacteria accelerated aging and caused disease. Emerging science from the Human Microbiome Project and the Metagenomics of Human Intestinal Tract projects has brought in a paradigm shift in our perception about
A MULTIDIMENSIONAL RADIATION MODEL FOR DIESEL ENGINE SIMULATION WITH COMPARISON TO EXPERIMENT

A radiation model based on the discrete ordinates method (DOM) was developed and integrated into the ERC version of KIVA-3V. The model was validated by comparison to an analytic solution and by comparison to previously published literature. In addition, the predicted radiative heat flux at a point on the head of a diesel engine was compared to experimentally measured values. The predicted radiative heat flux compared well with the experimental data both in phasing and peak intensity. Comparisons of the experimental radiative heat flux measurements to the predicted values using the mid-order (S4) DOM approximation with the radiation model showed good comparison to analytical solutions. For the other cases studied, a low-order (S2) DOM approximation was used since it required substantially fewer computer resources and was considered to be adequate. The low-order approximation results in a slight overprediction of the total heat loss between IVC and EVO (by about 1% compared to the mid-order approximation). ...
Constitutive in vitro binding of nuclear proteins to the 5'-fanking region of 6–16, a human gene inducible by α, β-interferons

Proteins in nuclear extracts of HeLa cells that constitutively bound in vitro to three regions upstream of the interferon-inducible gene 6–16 were separated partially by chromatography on DEAE-Sepharose. Region one, a CCAAT box in the non-coding strand at position −63 to −67, was protected from DNase digestion by the bound protein(s) and was required for transcription in vitro. Region two, a tandem duplication sequence at position −89 to −168 contains two copies of a sequence essential for strong induction of the 6–16 gene by interferon in vivo. Region three, a palindromic sequence at position −449 to −465, not necessary for induction of 6-16 by interferon, was also protected from DNase digestion by nuclear protein(s). Templates with or without regions of two and three were transcribed equally well in extracts from interferon-treated or untreated cells.
Differences in Bile Acid Excretion: Primary Hypercholesteremia Compared to Combined Hypercholesteremia and Hypertriglyceridemia

Total daily bile acid excretion was measured in 10 patients with primary hypercholesteremia and in nine patients with combined hypercholesteremia and hypertriglyceridemia by using 14C-labeled cholic acid and 3H-labeled chenodeoxycholic acid. The average bile acid excretion by the patients with primary hypercholesteremia was 282 mg/day; that by the patients with combined hypercholesteremia and hypertriglyceridemia, 1,094 mg/day. These findings suggest a fundamental difference in cholesterol metabolism in these two types of hyperlipidemia.
Varieties of joy-related pleasurable activities and feelings.

College students (N = 162) listed activities that they found pleasurable, and provided ratings of the degree to which those activities led them to feel each of 12 different joy-related pleasurable feelings. A factor analysis revealed three types of pleasurable feelings: cheerfulness, contentment, and enchantment. Participants also completed a personality inventory, the NEO-FFI, and a questionnaire developed for this study to measure pleasure elicited by three types of activities: social, intellectual, and basic needs (e.g., eating and sleeping). Different types of pleasure-eliciting activities were associated with different types of pleasurable experience, and the different types of pleasure-eliciting activities and pleasurable experiences were associated with different personality dimensions. For example, social activities were differentially associated with cheerfulness, and both social activities and cheerfulness were associated with extraversion; intellectual activities were differentially associated ...
In-Cylinder Injection of Oxygen-Enriched Air to Reduce Diesel Exhaust Emissions

The long time challenge for diesel engine manufacturers has been to reduce both particulate matter (PM) and NOx emissions simultaneously without sacrificing engine performance. One technique for reducing PM has been to inject air or oxygen-enriched air directly into the combustion chamber. Previous studies using the KIVA-3V computational fluid dynamics (CFD) model have shown benefits and the importance of the gas injection’s characteristics on the technique’s effectiveness in reducing emissions. Using a Caterpillar 3401E single cylinder engine, an experimental investigation has been conducted to demonstrate the effectiveness of an oxygen-enriched air injection system and fuel injection timing retard in reducing the NOx and the PM emissions in terms of both the particulate size and concentration. The gaseous emissions were measured using a Pierburg AMA 2000 gaseous emissions bench which included a chemiluminescent analyzer for NOx volumetric measurements, non-dispersive infrared (NDIR) analyzer for CO and CO2 measurements, and a parametric fuel cell for O2 measurements. PM emissions (i.e., soot particle concentration and size distribution) were measured using a TSI Model 3936 Scanning Mobility Particle Sizer (SMPS). The experimental observations regarding the effects of oxygen-enriched air injection on NOx and PM emissions were in accord with the previously reported results for late-cycle gas injection from a KIVA-3V model. The air injection technique additionally provided a low level of oxygen-enrichment during the compression cycle, with results similar to previous intake air oxygen-enrichment studies. A simultaneous reduction of NOx and particulates was demonstrated when the fuel injection timing characteristics were optimized in conjunction with the oxygen-enriched air injection. The experimental PM emissions were analyzed for number and size distributions and also found to be consistent with previously reported trends.Copyright © 2006 by ASME
CP violating rate asymmetries in B decays

We briefly discuss measurements of angles β and α of the unitarity triangle. We then review rate asymmetries usingSU(3) relationships in the standard model (SM). Some methods to measure angle y usingSU(3) are then discussed. We note that rate forb →sγ can be used to set limits on extra dimensions in which standard model particles propagate.
Diuretic use and the risk of breast cancer.

Some antihypertensive medications, particularly calcium channel blockers, have been associated with breast cancer risk, although the evidence is inconsistent. 1 Diuretics comprise the antihypertensive drug class with the longest record of use 2 and are one of the most commonly used drug classes in the United States, 3 yet have received less study than other antihypertensive classes. We have assessed the relation of diuretic use to the risk of invasive breast cancer using 30 years of data from our ongoing hospital-based case-control surveillance study.
Effects of anisotropic optical properties on photon migration in structured tissues

It is often adequate to model photon migration in human tissue in terms of isotropic diffusion or random walk models. A nearly universal assumption in earlier analyses is that anisotropic tissue optical properties are satisfactorily modelled by using a transport-corrected scattering coefficient which then allows one to use isotropic diffusion-like models. In the present paper we introduce a formalism, based on the continuous-time random walk, which explicitly allows the diffusion coefficients to differ along the three axes. The corrections necessitated by this form of anisotropy are analysed in the case of continuous-wave and time-resolved measurements and for both reflectance and transmission modes. An alternate model can be developed in terms of a continuous-time random walk in which the times between successive jumps differ along the three axes, but is not included here.
Local basis-dependent noise-induced Bell-nonlocality sudden death in tripartite systems

We demonstrate that multipartite Bell-inequality violations can be fully destroyed in finite time in three-qubit systems subject only to the mechanism of local external asymptotic dephasing noise. This broadens the study of local-noise-induced sudden death of nonlocal behavior, extending it beyond the realm of bipartite systems, to which it had previously been restricted.
Management of Atrial Fibrillation in the Emergency Department

Although atrial fibrillation remains the most common cardiac arrhythmia, the treatment and disposition remain varied. An accept-able standard of practice requires an evidence-based approach. This approach has revealed that half of the patients who present with acute atrial fibrillation will convert to sinus rhythm without intervention. In the hemodynamically stable subset, ascertaining the on-set of atrial fibrillation within 48 hours is critical because this period dictates when and if anticoagulation should be instituted and if and where electrical or chemical cardioversion needs be performed. The hemodynamically unstable patient, however, requires emergent cardioversion, irrespective of the chronicity of atrial fibrillation. An evidence-based approach may serve to optimize treatment and obviate the need for unnecessary hospital admissions.
Mass divergences of wide-angle scattering amplitudes

The mass divergences of wide-angle scattering amplitudes are examined in a class of field theories including those with elementary vector fields. Power-counting arguments are used to show that, apart from renormalization effects, the wide-angle gauge-singlet scattering amplitude has a well-defined zero-mass limit and hence satisfies the renormalization-group equations. The same techniques also reproduce the earlier results for Yukawa and ${\ensuremath{\varphi}}^{4}$ theories.
Adsorption in urine conversion

The need for a selective method for the removal of urea from urine is enhanced by the success of electrodialysis for removing electrolytes from urine. An investigation has been made of the capacities of an activated charcoal and an ion-exchange resin (Amberlite IR-120) for removal of urea from aqueous solution and from urine. In the charcoal column studies, determinations were made of the service time, the shape and thickness of the wavefront, and adsorbent capacity. The values of the adsorbent capacity of 6–14 and 50–200 mesh activated carbon are approximately 0.027 g. of urea/cm.3 gross volume of carbon. For column lengths of the order of the thickness of the wavefront, approximately 0.6 of the capacity is used before the effluent urea concentration reaches 5% of the influent concentration. On the average, one chloride ion is removed from urine for each 1.3 molecules of urea adsorbed. The capacity of the activated carbon in removing urea from aqueous solution is approximately 10% greater than that for removal of urea from urine. The capacities of Amberlite IR-120 ion-exchange resin are 0.023 and 0.090 g. of urea/cm.3 gross volume of resin for removal of urea from urine and from aqueous solution, respectively.
GABAA receptor activity and PKC control inhibitory synaptogenesis in CNS tissue slices

The molecular signals inducing the formation of inhibitory synapses early in development have remained enigmatic. Here we focus on the role of PKC and GABA(A)R receptor activation in the formation of GABAergic synapses in a natural cellular environment. Rapid synaptogenesis was observed in horizontal slices from the superior colliculus of embryonic (E19) rat, when GABA still acts as a depolarizing transmitter, excitatory synaptic activity is absent, and the number of already existing inhibitory synapses is very small. The vast majority of newly formed synapses expressed a GABAergic phenotype. Pharmacological block of GABA(A)R activation and Ca2+ influx through nifedipine-sensitive Ca2+ channels significantly enhanced the number of synaptic contacts, increased the immunoreactivity for GAD65, promoted synaptic accumulation of GABA(A)R clusters, and stimulated the generation of miniature IPSCs. The inhibitory synapse formation in situ was unconditionally prevented by PKC blockade and stimulated by PKC activation. Thus, a negative feedback relationship must exist between PKC and GABA(A)R activation. This new model of experimental synaptogenesis in brain slices promises to be a fruitful approach toward a better understanding of intracellular signaling cascades involved in the activity-regulated synapse formation, a problem of great clinical and theoretical relevance.
An investigation of path-goal leadership theory and its impact on intrachannel conflict and satisfaction

This path-analytic study examined the relationships among channel members’ perceptions of dimensions representing channel leader behavior, channel conflict and satisfaction. In doing so, the path-goal theory of leadership is tested in a franchise channel of distribution. The results indicate that both the consideration and the initiating structure dimensions of leader behavior significantly influence franchisees’ satisfaction with the franchise arrangement. As defined in the theory, these relationships were found to be mediated by the existing level of conflict being experienced by franchisees. Causal linkages are also found between intrachannel conflict and satisfaction. Specific recommendations are provided to franchisors and other channel leaders.
Coupling of optical and mechanical properties in crystalline polymers

The modules and birefringence of oriented polymers are known to couple through the structural and intrinsic properties of the polymer. Recent developments in both optical and mechanical theories have allowed this coupling to be expanded so that it includes predictions of modulus and refractive indices of uniaxially-oriented polymer films at various angles to the draw direction. The validity of these theories has been tested in this study by predicting the angular dependence of the optical and mechanical properties of seven uniaxiallyoriented films of isotactic polypropylene. The present study also provides intrinsic material properties associated with the crystalline and noncrystalline components of the polymer, and consequently allows the identification of the structural parameters that control the properties of ultra-high oriented isotactic polypropylene.
A Double-Edged Sword: Globalization and Biosecurity

A common argument since the terrorist attacks in New York and Washington, D.C., on September 11, 2001, is that while economic globalization brings enhanced efficiency, this comes at the cost of greater vulnerability to terrorism. Audrey Kurth Cronin maintains, "The current wave of international terrorism, characterized by unpredictable and unprecedented threats from nonstate actors, not only is a reaction to globalization but is facilitated by it."' "It would be naive to assume," says Cronin, "that what is good for international commerce and communication is not also good for international terrorists."2 Similarly, Kurt Campbell contends, "Much has been written about the forces of globalization-the relentless expansion of market forces and the constant search for greater economic efficiencies. . . . Many of the things that have left Western societies vulnerable to terrorist attacks are the very efficiencies that have come as a consequence of the relentless search for efficiency and the maximization of productivity, by person, companies, and countries."' Stanley Hoffman argues that Islamic terrorism is partly fueled by "a resistance to 'unjust' economic globalization. . . . Insofar as globalization enriches some and uproots many, those who are both poor and uprooted may seek revenge and self-esteem in terrorism."4
An electron-spin-resonance study of polyaniline and its derivatives: polymer interactions with moisture

Abstract The electronic behavior of polyaniline is sensitively dependent on moisture. For example, pumping under vacuum leads to an order of magnitude smaller conductivity, increased dielectric constant, and increased Curie susceptibility. An understanding of the mechanism of conductivity enhancement and changes in the other properties due to absorbed moisture thus requires better insight into the nature of the absorbed water. An electron spin resonance study has therefore been undertaken to find the various absorption/adsorption sites for water molecules. A number of experiments has been performed which lead us to propose a “variable-size metallic island” model. That is, protonated and highly ordered regions (metallic islands) are separated from unprotonated and amorphous regions by a less ordered region, whose width depends on the amount of moisture present in the sample. The water in the boundary region reduces its width by introducing order and thereby transforming partly localized polarons into bipolarons. The conductivity enhancement is argued to be due to increased size of the metallic islands in the presence of moisture.
Chronic Salmonella Infected Mouse Model

The bacterial infected mouse model is a powerful model system for studying areas such as infection, inflammation, immunology, signal transduction, and tumorigenesis. Many researchers have taken advantage of the colitis induced by Salmonella typhimurium for the studies on the early phase of inflammation and infection. However, only few reports are on the chronic infection in vivo. Mice with Salmonella persistent existence in the gastrointestinal tract allow us to explore the long-term host-bacterial interaction, signal transduction, and tumorigenesis. We have established a chronic bacterial infected mouse model with Salmonella typhimurium colonization in the mouse intestine over 6 months. To use this system, it is necessary for the researcher to learn how to prepare the bacterial culture and gavage the animals. We detail a methodology for prepare bacterial culture and gavage mice. We also show how to detect the Salmonella persistence in the gastrointestinal tract. Overall, this protocol will aid researchers using the bacterial infected mouse model to address fundamentally important biological and microbiological questions.
Biomechanical comparison of single-row arthroscopic rotator cuff repair technique versus transosseous repair technique

This study determined the effect of tear size on gap formation of single-row simple-suture arthroscopic rotator cuff repair (ARCR) vs transosseous Mason-Allen suture open RCR (ORCR) in 13 pairs of human cadaveric shoulders. A massive tear was created in 6 pairs and a large tear in 7. Repairs were cyclically tested in low-load and high-load conditions, with no significant difference in gap formation. Under low-load, gapping was greater in massive tears. Under high-load, there was a trend toward increased gap with ARCR for large tears. All repairs of massive tears failed in high-load. Gapping was greater posteriorly in massive tears for both techniques. Gap formation of a modeled RCR depends upon the tear size. ARCR of larger tears may have higher failure rates than ORCR, and the posterior aspect appears to be the site of maximum gapping. Specific attention should be directed toward maximizing initial fixation of larger rotator cuff tears, especially at the posterior aspect.
The health bar: a persuasive ambient display to improve the office worker's well being

Recent research studies have shown the serious health risks associated with prolonged sitting. Standing up and walking on a regular basis has been proved to improve an office worker's well-being. Small behavioral changes like the aforementioned are the basis of preventive medicine and even though they appear easy to follow, in practice are difficult to apply. Advances in technology miniaturization and smart sensors are paving the way for the development of devices that empower preventive medicine. These devices use the power of persuasion to help people change behavior and maintain well-being. They act as an ambient personal 'coach' that monitors and intervenes at the right time. In this paper we present the HealthBar, an ambient persuasive device that helps users break up their prolonged sitting habits.
A Protein Thermometer Controls Temperature-Dependent Transcription of Flagellar Motility Genes in Listeria monocytogenes

Facultative bacterial pathogens must adapt to multiple stimuli to persist in the environment or establish infection within a host. Temperature is often utilized as a signal to control expression of virulence genes necessary for infection or genes required for persistence in the environment. However, very little is known about the molecular mechanisms that allow bacteria to adapt and respond to temperature fluctuations. Listeria monocytogenes (Lm) is a food-borne, facultative intracellular pathogen that uses flagellar motility to survive in the extracellular environment and to enhance initial invasion of host cells during infection. Upon entering the host, Lm represses transcription of flagellar motility genes in response to mammalian physiological temperature (37°C) with a concomitant temperature-dependent up-regulation of virulence genes. We previously determined that down-regulation of flagellar motility is required for virulence and is governed by the reciprocal activities of the MogR transcriptional repressor and the bifunctional flagellar anti-repressor/glycosyltransferase, GmaR. In this study, we determined that GmaR is also a protein thermometer that controls temperature-dependent transcription of flagellar motility genes. Two-hybrid and gel mobility shift analyses indicated that the interaction between MogR and GmaR is temperature sensitive. Using circular dichroism and limited proteolysis, we determined that GmaR undergoes a temperature-dependent conformational change as temperature is elevated. Quantitative analysis of GmaR in Lm revealed that GmaR is degraded in the absence of MogR and at 37°C (when the MogR:GmaR complex is less stable). Since MogR represses transcription of all flagellar motility genes, including transcription of gmaR, changes in the stability of the MogR:GmaR anti-repression complex, due to conformational changes in GmaR, mediates repression or de-repression of flagellar motility genes in Lm. Thus, GmaR functions as a thermo-sensing anti-repressor that incorporates temperature signals into transcriptional control of flagellar motility. To our knowledge, this is the first example of a protein thermometer that functions as an anti-repressor to control a developmental process in bacteria.
Analytical formulation of mode-coupling instability in disc-pad coupled system

Abstract This paper describes the mode-coupling-type squeal mechanism in a disc brake system. The mode shapes of a disc and a brake pad (an annular sector plate) are obtained using the component eigenvalue analysis and the Rayleigh–Ritz method, respectively. The disc–pad coupled system subject to friction-couple is discretized by the truncated set of system component modes. Mode-coupling instability is determined in closed form resulting from a reduced-order friction-coupling model, which subsequently defines the modal stability index. The proposed index parameter determines the necessary condition for flutter instability without solving system complex eigenvalues. The numerical investigation shows that the disc–pad modal interaction has a strong squeal tendency when two pads are not identical.
Superconductivity with Soft Lattice Modes in LaBaCuO and YBaCuO

The canonical transformation employed in polaron theory at intermediate coupling is generalized to the electron phonon interaction of an entire band of electrons. Interelectron interactions result. The overall lattice-electron correlation is obtained with a variational calculation, balancing the extra elastic energy stored in the lattice against the negative energy arising from BCS pair correlation. The requisite phonon softening to attain any given value of Tc in metallic LaBaCuO and YBaCuO are estimated. The implicit fluctuations in the lattice normal coordinates are compared with results yielded by the EXAFS measurements of Oyanagi et al.
Switching and impulsive control of a reflected diffusion

This paper is concerned with the optimal control of a reflected diffusion. The process is controlled by switching the control mode and by impulsing the state of the process. With Bensoussan-Lions' result on stopping time problems, two quasi-variational inequalities are solved as the dynamic programming equations for a discounted cost and a long run average cost criterions.
A Liouville comparison principle for solutions of semilinear elliptic partial differential inequalities

This work is devoted to the study of a Liouville-type comparison principle for entire weak solutions of semilinear elliptic partial differential inequalities of the form $$ \mathcal{L}u+|u|^{q-1}u \leq\mathcal{L}v+|v|^{q-1}v, $$ where $q>0$ is a given real number and $\mathcal{L}$ is a linear (possibly non-uniformly) elliptic partial differential operator of second order in divergence form given by the relation $$ \mathcal{L}=\sum_{i,j=1}^n\frac{\partial}{\partial x_i}\bigg[a_{ij}(x)\frac{\partial}{\partial x_j}\bigg]. $$ We assume that $n\geq2$ , that the coefficients $a_{ij}(x)$ , $i,j=1,\dots,n$ , are measurable bounded functions on $\mathbb{R}^n$ such that $a_{ij}(x)=a_{ji}(x)$ and that the corresponding quadratic form is non-negative. The results obtained in this work were announced by the author in 2005.
Low-power multiple-bit upset tolerant memory optimization

In this paper, we propose a framework for analyzing Soft Error Rates (SER) including Multiple-Bit Upsets (MBU). Then, using this framework, we optimize the soft error tolerant voltage (V tol ) and interleaving distance (ID) of low-power, error-tolerant memories. Experimental results show that the total power can be reduced by an average of 30.5% with V tol optimization and an average of 40.9% by simultaneously considering V tol and ID together when compared to worst-case design practices.
Intracellular Copper Does Not Catalyze the Formation of Oxidative DNA Damage in Escherichia coli

Because copper catalyzes the conversion of H2O2 to hydroxyl radicals in vitro, it has been proposed that oxidative DNA damage may be an important component of copper toxicity. Elimination of the copper export genes, copA, cueO, and cusCFBA, rendered Escherichia coli sensitive to growth inhibition by copper and provided forcing circumstances in which this hypothesis could be tested. When the cells were grown in medium supplemented with copper, the intracellular copper content increased 20-fold. However, the copper-loaded mutants were actually less sensitive to killing by H2O2 than cells grown without copper supplementation. The kinetics of cell death showed that excessive intracellular copper eliminated iron-mediated oxidative killing without contributing a copper-mediated component. Measurements of mutagenesis and quantitative PCR analysis confirmed that copper decreased the rate at which H2O2 damaged DNA. Electron paramagnetic resonance (EPR) spin trapping showed that the copper-dependent H2O2 resistance was not caused by inhibition of the Fenton reaction, for copper-supplemented cells exhibited substantial hydroxyl radical formation. However, copper EPR spectroscopy suggested that the majority of H2O2-oxidizable copper is located in the periplasm; therefore, most of the copper-mediated hydroxyl radical formation occurs in this compartment and away from the DNA. Indeed, while E. coli responds to H2O2 stress by inducing iron sequestration proteins, H2O2-stressed cells do not induce proteins that control copper levels. These observations do not explain how copper suppresses iron-mediated damage. However, it is clear that copper does not catalyze significant oxidative DNA damage in vivo; therefore, copper toxicity must occur by a different mechanism.
Reliability Sampling Methodology Using Simulation and Re-Sampling

This paper develops and validates a reliability sampling methodology using simulation, and re-sampling; and which incorporates unit-to-unit variation in the determination of significant sample sizes for analytically intractable reliability cases. This sample size determination is very important because the reliability of the sampled vehicles should represent the reliability of the entire fleet. Smaller-than-required sample sizes may lead to an incorrect representation of the reliability of the fleet, which may mislead the Army to make poor decisions, such as deploying a fleet that may not be reliable. These type II errors can be minimized by incorporating a more realistic sampling methodology, as developed in this research. Prior to using this methodology, analytical formulas were used to compute reliability sample sizes with unit-to-unit variation assumed to be constant. This new methodology confirms the analytically derived solutions for fixed usage & true failure rate, as well as for fixed usage & varying vehicle true failure rate. Existing reliability data shows that unit-to-unit variation does exist. Vehicle variation in true failure rate is modeled with a Gamma prior distribution. Recent reliability data are used to validate the hypothesis that this is an adequate tool for reliability sampling when unit-to-unit variation exists. Results of this validation accept the hypothesis, validating that the methodology is an adequate tool. The Army is currently using this methodology for fleet assessment
Aerosol observations for climate studies

The Stratospheric Aerosol Measurement II and Stratospheric Aerosol and Gas Experiment satellite systems have provided to date more than five years and almost three years, respectively, of data on atmospheric aerosol profiles on a near-global scale. Studies with these unique data sets are developing a global aerosol climatology for the first time and have shown the existence and quantification of polar stratospheric clouds and tropical stratospheric cirrus. In addition, a tropospheric cirrus climatology is evolving. Since these two experiments were launched, a series of large volcanic eruptions have occurred which have greatly impacted the stratospheric aerosol loading. The aerosol layer produced by the eruption of El Chichon, for example, increased the 30 mb temperatures in the northern tropics by as much as 4 C for six months after the eruption. This paper describes in detail, from a climate perspective, the evolving aerosol and cloud climatologies as a function of space and time, and shows the stratospheric dynamics of volcanic injections and their enhancements on stratospheric optical depth and mass loading.
Tea Ceremony and Tatami Mat Making: Gender Differences in Access to Educational Programs in Japanese Prisons

Gender roles in the larger society are often reflected in prisons: Female inmates in most countries are confronted with prison conditions that are different from those of male prisoners. The goal of this study is to ascertain if the same holds true for Japan. We administered questionnaires to inmates in two prisons in Japan (N = 174) and conducted face-to-face interviews with officials in the same institutions concerning educational and vocational programs available to inmates. Our results indicate that fewer programs are found in prisons for females and that these programs reflect the traditional role of women in Japan.
Neural-tube defects in a prehistoric south-western Indian population

SummaryConcern with the frequency and patterning of the occurrence of midline neural-tube defects among contemporary human populations is widespread. These defects are, however, quite old and occur in unusually high numbers of prehistoric skeletons. A common explanation offered for such high incidence has been inbreeding among small, reproductively isolated populations. In a sample of 54 skeletons from the prehistoric south-western Indian site of Tijeras Pueblo in New Mexico, failure of neural-tube closure occurs in 10% of sacra recovered. While a more homogeneous genetic background and inbreeding may account for a portion of this elevated prevalence, the cause appears to lie with cultural-environmental factors. It is suggested that the aetiology of these conditions has become more complex in recent human history.
A Multiple-Spark Light Source and Camera for Schlieren and Silhouette Photography

A multiple-spark light source and camera utilizing the Cranz-Schardin optical method for schlieren and silhouette photography is described. Each light source is a spark in air, with an effective duration of 10-7 second and a peak of light of 24,000 candle power. The interval between successive sparks is independently adjustable from 10-5 to 10-7 second, permitting a variable picture rate to be used in a single sequence of photographs. The equipment contains ten spark light sources and camera lenses, permitting a ten picture sequence of high speed phenomena. Schlieren and silhouette photographs demonstrating the performance of the equipment are presented.
Development of a D genome specific marker resource for diploid and hexaploid wheat.

Mapping and map-based cloning of genes that control agriculturally and economically important traits remain great challenges for plants with complex highly repetitive genomes such as those within the grass tribe, Triticeae. Mapping limitations in the Triticeae are primarily due to low frequencies of polymorphic gene markers and poor genetic recombination in certain genetic regions. Although the abundance of repetitive sequence may pose common problems in genome analysis and sequence assembly of large and complex genomes, they provide repeat junction markers with random and unbiased distribution throughout chromosomes. Hence, development of a high-throughput mapping technology that combine both gene-based and repeat junction-based markers is needed to generate maps that have better coverage of the entire genome. In this study, the available genomics resource of the diploid Aegilop tauschii, the D genome donor of bread wheat, were used to develop genome specific markers that can be applied for mapping in modern hexaploid wheat. A NimbleGen array containing both gene-based and repeat junction probe sequences derived from Ae. tauschii was developed and used to map the Chinese Spring nullisomic-tetrasomic lines and deletion bin lines of the D genome chromosomes. Based on these mapping data, we have now anchored 5,171 repeat junction probes and 10,892 gene probes, corresponding to 5,070 gene markers, to the delineated deletion bins of the D genome. The order of the gene-based markers within the deletion bins of the Chinese Spring can be inferred based on their positions on the Ae. tauschii genetic map. Analysis of the probe sequences against the Chinese Spring chromosome sequence assembly database facilitated mapping of the NimbleGen probes to the sequence contigs and allowed assignment or ordering of these sequence contigs within the deletion bins. The accumulated length of anchored sequence contigs is about 155 Mb, representing ~ 3.2 % of the D genome. A specific database was developed to allow user to search or BLAST against the probe sequence information and to directly download PCR primers for mapping specific genetic loci. In bread wheat, aneuploid stocks have been extensively used to assign markers linked with genes/traits to chromosomes, chromosome arms, and their specific bins. Through this study, we added thousands of markers to the existing wheat chromosome bin map, representing a significant step forward in providing a resource to navigate the wheat genome. The database website ( http://probes.pw.usda.gov/ATRJM/ ) provides easy access and efficient utilization of the data. The resources developed herein can aid map-based cloning of traits of interest and the sequencing of the D genome of hexaploid wheat.
The clinical management of hemophilia and head trauma: a survey of current clinical practice among pediatric hematology/oncology physicians.

Background Determining the appropriate evaluation for a pediatric patient with hemophilia and head trauma is a diagnostic challenge with no neuroimaging guidelines and limited clinical evidence to direct care. Procedure A questionnaire, with two case scenarios, was emailed to members of the American Society of Pediatric Hematology/Oncology. The case scenarios involved asymptomatic toddlers with severe hemophilia who had either fallen from a height (case 1) or from standing (case 2). Respondents were asked to select from six management options. The case scenarios were then altered to include: a large palpable hematoma, prophylactic factor infusion 24 hr prior, the trauma occurred 48 hr prior, wearing a soft helmet, or emesis. Results The completed response rate was 23% (252/1,077). Computed tomography (CT) was selected by 68.9% (#1) and 56.4% (#2) of respondents. In both case scenarios the presence of a palpable bruise resulted in a statistically significant increase in CT usage to 83.7% and 82.8% (P < 0.001). The use of prophylaxis did not result in a statistically significant decrease in CT usage. Duration of factor replacement was variable ranging from 1 to 4 days. Conclusion Physician self reported management of pediatric patients with hemophilia and head trauma is diverse. The use of CT imaging for mild head trauma in patients without signs or symptoms of intracranial hemorrhage was very common. The use of prophylaxis did not reduce the use of head CT imaging. This variation in clinical practice demonstrates the lack of evidence regarding the management of head trauma in patients with hemophilia. Pediatr Blood Cancer 2009;53:406–410. © 2009 Wiley-Liss, Inc.