cssi/SciSciGPT-SciSciNet huggingface dataset:
A simple technique for avoiding convergence problems in finite element simulations of crack nucleation and growth on cohesive interfaces

Numerical simulations of crack initiation which use a cohesive zone law to model a weak interface in the solid are often limited by the occurrence of an elastic snap-back instability. At the point of instability, quasi-static finite element computations are unable to converge to an equilibrium solution, which usually terminates the calculation and makes it impossible to follow the post-instability behaviour. In this paper, we show that such numerical difficulties can easily be avoided by introducing a small viscosity in the constitutive equations for the cohesive interface. Simple boundary value problems are used to develop guidelines for selecting appropriate values of viscosity in numerical simulations involving crack nucleation and growth. As a representative application, we model crack nucleation at the interface between an elastic thin film and an elastic–plastic substrate, which is subjected to contact loading.
Phase diversity for three-dimensional imaging

Phase diversity (PD) is a powerful technique for estimating wavefront aberrations from two-dimensional images of extended scenes. PD can work with extended incoherent images and, in an adaptive optics system, does not need extra hardware in addition to the deformable mirror. For these reasons, PD should be well suited to aberration measurement in microscopy applications. But, in biological widefield microscopy, the objects being imaged are frequently three-dimensional, and the images contain out-of-focus light. In this paper, we introduce multiplane PD and show that PD can be extended to widefield imaging of three-dimensional objects. This should be particularly useful in the field of biological fluorescence microscopy where the objects are very light sensitive and the aberrations cannot easily be determined.
A new model for thin plates with rapidly varying thickness

Abstract We study the bending of a thin plate with rapidly varying thickness, for example one with rib-like stiffeners or perforated by small holes. We obtain a fourth-order equation for the midplanc displacement, using an asymptotic analysis based on three-dimensional linear elasticity. The coefficients of this equation represent the constitutive law relating bending moments to midplane curvature; they are explicitly determined by the plate geometry. Our analysis distinguishes between three different cases, in which the thickness varies on a length scale longer than, on the order of, or shorter than the mean thickness.
Disparities in access to health care among adults with physical disabilities: analysis of a representative national sample for a ten-year period.

Abstract Background People with physical disabilities are the largest underserved subpopulation in the U.S. However, disparities in access to health care and how these have changed over time have not been fully explored. Objective To examine national trends in disparities in access to health care and to identify the impact of physical disability and the personal factors that are associated with unmet health care needs, defined as self-reported ability to get medical care, dental care or prescription medications, among working age adults within the United States. Methods Logistic regression analysis of a nationally representative sample of adults ages 25–64 (n = 163,220) with and without physical disabilities, using pooled data from the 2002–2011 Medical Expenditure Panel Survey. Results Individuals with physical disabilities have 75% (p Conclusion Having physical disabilities increase the odds of unmet health care needs. This study has important policy and community program implications. The Affordable Care Act could significantly reduce unmet health care needs, especially among individuals with physical disabilities.
The Summer Institute Project (Cambio Social Cruzando Fronteras): Transnationalisms, Transdisciplinarities, and Transformations in Latino Studies

The coming together of Latin American Studies and Latino Studies is a growing trend on university campuses, partly reflecting an attempt to better understand social processes of globalization and migration. Yet, there are real tensions between the fields due to differences in origins, degree of interdiscliplinarity, and epistemology. One way to bridge the academic gaps may be through tethering such programs in the sort of community accountability called for by Juan Flores, Antonia Darder, Rudy Torres, and others. This article reviews one such attempt through a community–university partnership that for six years brought together activists from Latin American and US Latino communities. We discuss the impacts this projects had on both the activists and their academic partners.
Effect of hypothermia on the thalamocortical function in the rat model

Neuroprotective effects of hypothermia are well documented in many injuries of the central nervous system in animal models as well as clinical studies. However, the underlying mechanisms are not fully understood. An important yet unexplored background issue is the effect of hypothermic cooling on the regional functionality of the healthy CNS. In a pilot study with the rat model, we seek to characterize the effect of moderate bodily cooling on the thalamo-cortical (T-C) function. Multiunit activity (MUA) and local field potentials (LFPs) were recorded from the thalamus (VPL nucleus) and the somatosensory cortex (S1) for normothermic, mild hypothermic and mild hyperthermic conditions in healthy rats and the thalamo-cortical dynamics was characterized with Granger Causal Interaction (GCI). The GCI indicated that the thalamic driving of the cortical activity significantly increases in strength with bodily cooling and weakens with mild heating. These results could have important implications towards understanding of hypothermia.
Africa's Refugee Crisis: State Building in Historical Perspective

There is a refugee crisis in Africa. A resort to war as a substitute for politics has pushed massive numbers of Africans beyond state borders. This article examines the historical roots of internal...
Roles of the N- and C-Terminal Domains of Mammalian Mitochondrial Initiation Factor 3 in Protein Biosynthesis

Abstract Bacterial initiation factor 3 (IF3) is organized into N- and C-domains separated by a linker. Mitochondrial IF3 (IF3 mt ) has a similar domain organization, although both domains have extensions not found in the bacterial factors. Constructs of the N- and C-domains of IF3 mt with and without the connecting linker were prepared. The K d values for the binding of full-length IF3 mt and its C-domain with and without the linker to mitochondrial 28S subunits are 30, 60, and 95 nM, respectively, indicating that much of the ribosome binding interactions are mediated by the C-domain. However, the N-domain binds to 28S subunits with only a 10-fold lower affinity than full-length IF3 mt . This observation indicates that the N-domain of IF3 mt has significant contacts with the protein-rich small subunit of mammalian mitochondrial ribosomes. The linker also plays a role in modulating the interactions between the 28S subunit and the factor; it is not just a physical connector between the two domains. The presence of the two domains and the linker may optimize the overall affinity of IF3 mt for the ribosome. These results are in sharp contrast to observations with Escherichia coli IF3. Removal of the N-domain drastically reduces the activity of IF3 mt in the dissociation of mitochondrial 55S ribosomes, although the C-domain itself retains some activity. This residual activity depends significantly on the linker region. The N-domain alone has no effect on the dissociation of ribosomes. Full-length IF3 mt reduces the binding of fMet–tRNA to the 28S subunit in the absence of mRNA. Both the C-terminal extension and the linker are required for this effect. IF3 mt promotes the formation of a binary complex between IF2 mt and fMet–tRNA that may play an important role in mitochondrial protein synthesis. Both domains play a role promoting the formation of this complex.
EXTREME VALUES OF BIRTH AND DEATH PROCESSES AND QUEUES

We study the asymptotic behavior of maximum values of birth and death processes over large time intervals. In most cases, the distributions of these maxima, under standard linear normalizations, either do not converge or they converge to a degenerate distribution. However, by allowing the birth and death rates to vary in a certain manner as the time interval increases, we show that the maxima do indeed have three possible limit distributions. Two of these are classical extreme value distributions and the third one is a new distribution. This third distribution is the best one for practical applications. Our results are for transient as well as recurrent birth and death processes and related queues. For transient processes, the focus is on the maxima conditioned that they are finite.
High performance computer aided detection system for polyp detection in CT colonography with fluid and fecal tagging

CT colonography (CTC) is a feasible and minimally invasive method for the detection of colorectal polyps and cancer screening. Computer-aided detection (CAD) of polyps has improved consistency and sensitivity of virtual colonoscopy interpretation and reduced interpretation burden. A CAD system typically consists of four stages: (1) image preprocessing including colon segmentation; (2) initial detection generation; (3) feature selection; and (4) detection classification. In our experience, three existing problems limit the performance of our current CAD system. First, highdensity orally administered contrast agents in fecal-tagging CTC have scatter effects on neighboring tissues. The scattering manifests itself as an artificial elevation in the observed CT attenuation values of the neighboring tissues. This pseudo-enhancement phenomenon presents a problem for the application of computer-aided polyp detection, especially when polyps are submerged in the contrast agents. Second, general kernel approach for surface curvature computation in the second stage of our CAD system could yield erroneous results for thin structures such as small (6-9 mm) polyps and for touching structures such as polyps that lie on haustral folds. Those erroneous curvatures will reduce the sensitivity of polyp detection. The third problem is that more than 150 features are selected from each polyp candidate in the third stage of our CAD system. These high dimensional features make it difficult to learn a good decision boundary for detection classification and reduce the accuracy of predictions. Therefore, an improved CAD system for polyp detection in CTC data is proposed by introducing three new techniques. First, a scale-based scatter correction algorithm is applied to reduce pseudo-enhancement effects in the image pre-processing stage. Second, a cubic spline interpolation method is utilized to accurately estimate curvatures for initial detection generation. Third, a new dimensionality reduction classifier, diffusion map and local linear embedding (DMLLE), is developed for classification and false positives (FP) reduction. Performance of the improved CAD system is evaluated and compared with our existing CAD system (without applying those techniques) using CT scans of 1186 patients. These scans are divided into a training set and a test set. The sensitivity of the improved CAD system increased 18% on training data at a rate of 5 FPs per patient and 15% on test data at a rate of 5 FPs per patient. Our results indicated that the improved CAD system achieved significantly better performance on medium-sized colonic adenomas with higher sensitivity and lower FP rate in CTC.
The effect of substrate temperature and reactant gas pressure on the chemical vapor deposition of tungsten films

The growth kinetics, crystal morphology and mechanical behavior of chemically vapor deposited tungsten films are strongly affected by substrate temperature. Lower substrate temperatures results in vastly stronger and harder materials. For example, a temperature of 500°C resulted in material with a higher yield strength than did a temperature of 700 °C. The difference amounted to 3000 psi∗ at four test temperatures between 200 °C and 800 °C. Deposition pressure had little effect on film strength or appearance. Pressures of 300 and 500 torr were evaluated for deposits made at 500 °C. The main structural difference observed between films produced at the two substrate temperatures was that at 700 °C the columnar grains grew straight through the film but at 500 °C there was a “fanning out” or a distribution in growth directions through the film thickness. Scanning electron microscopy reveals that the individual tungsten crystals advance with four sided pyramids at the interface, similar in appearance to those found in the electrodeposition of copper single crystals. We find that these pyramids become steeper and more irregular with increasing substrate temperature. The pyramids have {111} surfaces, and propagate by the advance of ledges up the {111} facets. An activation energy of 16 kcal/mole was determined for film growth, indicative of control by surface diffusion, adsorption and desorption processes.
Studies of the toxicity of isonicotinic acid hydrazide (isoniazid) to ducklings

Abstract Studies were undertaken to more accurately establish the dose response of ducklings to isoniazid. Specific trials were included to determine variation associated with dose level, route of administration, and species. Microscopic evaluation of the tissue alterations induced by the drug in the various trials was carried out. Dietary administration of isoniazid to Pekin ducks was studied in trial I, and the LD 50 at 7 days was 0.13% with a 95% confidence interval of 0.118 – 0.142%. Rouen ducks appeared to be slightly less susceptible to the toxic effects of dietary administered INH. The dose effect line established in trial II was parallel to that determined for the Pekin duck, but 0.04% higher at the 50% mortality level. Isoniazid given by intraperitoneal injection to Pekin ducks (trial III) was acutely toxic at levels greater than 100 mg per kilogram of body weight. The LD 50 at 7 days established for intraperitoneal injection was 57 mg/kg with a 95% confidence interval dosage of 53.0–61.3 mg/kg. A comparison of parenteral toxicity of INH in Rouen ducks (trial IV) revealed no significant difference in dose effect response between the two breeds. Subacute toxicity study (trial V) established the following time periods for 50% mortality when INH was administered in the diet: 13 days with 0.10%; 18 days with 0.09%; 11 days with 0.08%, 21 days with 0.75%, and 29 days with 0.05% INH. Clinical signs of toxicosis were not observed during the first two months of treatment in groups of ducks receiving 0.001% or 0.005% INH. Twenty percent mortality occurred in the group fed 0.01% INH during first three months of treatment.
Fish, n-3 fatty acids, and cardiovascular haemodynamics.

Consistent evidence indicates that modest consumption of fish or fish oil supplementation lowers the incidence of cardiac death and possibly other cardiovascular events. Precise physiologic mechanisms accounting for such reduced clinical risk are not well understood. Animal-experimental studies, ran
A non-negative moment-preserving spatial discretization scheme for the linearized Boltzmann transport equation in 1-D and 2-D Cartesian geometries

We present a new nonlinear spatial finite-element method for the linearized Boltzmann transport equation with S n angular discretization in 1-D and 2-D Cartesian geometries. This method has two central characteristics. First, it is equivalent to the linear-discontinuous (LD) Galerkin method whenever that method yields a strictly non-negative solution. Second, it always satisfies both the zeroth and first spatial moment equations. Because it yields the LD solution when that solution is non-negative, one might interpret our method as a classical fix-up to the LD scheme. However, fix-up schemes for the LD equations derived in the past have given up solution of the first moment equations when the LD solution is negative in order to satisfy positivity in a simple manner. We present computational results comparing our method in 1-D to the strictly non-negative linear exponential-discontinuous method and to the LD method. We present computational results in 2-D comparing our method to a recently developed LD fix-up scheme and to the LD scheme. It is demonstrated that our method is a valuable alternative to existing methods.
Hydrothermal minerals and alteration rates at Surtsey volcano, Iceland

The volcanic island Surtsey, off the south coast of Iceland, was created by volcanic activity in 1963–1967. Core from a 181-m-deep hole extending 123 m below sea level shows the results of 12 yr of hydrothermal alteration of basaltic tephra. The primary cause of heating of the tephra and of development of the hydrothermal system was the intrusion of dikes below sea level. At present, the hottest part of the hole, at a maximum temperature of 150 °C, is cooling at ∼0.9 °C per year. Palagonitization of sideromelane glass, a dominant constituent of the tephra, is an important alteration process that is strongly temperature dependent, the rate doubling for every 12 °C increase. At 60 °C, 90% is palagonitized. Above 120 °C, olivine crystals are replaced on their edges by nontronite; the thickness of clay doubles for each 8 °C increase. Ten hydrothermal minerals have crystallized in the tephra at 25 to 150 °C; the dominant species are smectite (nontronite), analcite, phillipsite, and tobermorite. The primary clay species of palagonite is probably nontronite. Other minerals are halite, opal, calcite, chabazite, xonotlite, anhydrite, and gypsum. No major differences in mineral occurrence are noted above and below sea level, but phillipsite and tobermorite tend to grow larger below sea level, even at the same temperature. Analcite appears at lower temperature (55 °C) above sea level than below sea level (75 °C). Anhydrite is most abundant deep in the hole, where inflowing, cool sea water precipitated sulfate due to reduced sulfate solubility at higher temperatures.
Aircraft Instrument for Comprehensive Characterization of Aerosol Optical Properties, Part 2: Black and Brown Carbon Absorption and Absorption Enhancement Measured with Photo Acoustic Spectroscopy

This paper describes the design and performance of a photo-acoustic aerosol absorption spectrometer (PAS) built for operation on a research aircraft platform. The PAS instrument is capable of measuring dry absorption at 659 nm, 532 nm, and 404 nm, and absorption enhancement due to coatings at 532 nm and 404 nm. The measurement accuracy for all channels is < = 10% and in flight 1 Hz sensitivities lie within the range of 0.5–1.5 Mm−1. PAS measurements of calibrated absorbing aerosol samples are shown to be consistent with measurements made by a previous generation single channel photo-acoustic instrument. Aircraft data collected during a recent field campaign in California are used to demonstrate the capabilities of the PAS. In combination with an aircraft cavity ring down aerosol extinction spectrometer described in a companion paper, the new PAS instrument provides a sensitive airborne in-situ characterization of aerosol optics. Copyright 2012 American Association for Aerosol Research
Association of sex with perioperative mortality and morbidity after carotid endarterectomy for asymptomatic carotid stenosis

Abstract Objective: To examine whether perioperative morbidity and mortality after carotid endarterectomy depend on the sex and the presence of symptoms on presentation. Design: Retrospective review of quality assurance database prospectively collected. Setting: A university teaching hospital. Participants: One thousand two hundred eighty-seven patients who had 1,503 carotid endarterectomies from 1990 to 1999 from a quality assurance database. Interventions: None. Measurements and Main Results: The cases were divided into 4 groups by sex and symptoms on presentation: male-symptomatic (MS), male-asymptomatic (MA), female-symptomatic (FS), and female-asymptomatic (FA). The 4 groups were compared for preoperative demographic and comorbidity profiles, carotid plaque characteristics, and outcome. Outcome measures included in-hospital stroke, myocardial infarction (MI), congestive heart failure (CHF), and death. There were 496 cases in the MS group, 407 in the MA group, 315 in the FS group, and 285 in the FA group. Women were less likely to have a history of coronary artery disease, prior MI, or smoking, and their carotid plaques were less likely to be ulcerated or contain intraplaque hemorrhage. Even when controlling for the comorbidities and plaque characteristics, the incidence of each of the complications examined was low and not significantly different between the sexes in both the symptomatic and asymptomatic groups. The rate of stroke or death was 3.0% (MS) versus 1.9% (FS) (p = NS) and 1.2% (MA) versus 1.8% (FA) (p = NS). Conclusion: There is no significant sex difference in perioperative cardiac or cerebrovascular complications. Women with symptomatic or asymptomatic carotid stenosis can have acceptably low complication rates from carotid endarterectomy and may benefit from the surgery as much as men. Copyright 2003, Elsevier Science (USA). All rights reserved.
The Thickness of Tectonic Plates

A fundamental premise of plate tectonics on Earth is that rigid lithospheric plates, formed at mid-ocean ridges, float above a more deformable substratum, the asthenosphere ( 1 ). The precise nature of the asthenosphere is still debated. Mechanical models predict a well-defined, sharp lithosphere-asthenosphere boundary (LAB), but evidence for such a boundary from conventional seismic measurements is ambiguous. On pages [499][1] and [495][2] of this issue, Kawakatsu et al. ( 2 ) and Rychert and Shearer ( 3 ) present analyses of more sophisticated seismic studies that help refine the LAB and hence the thickness of the lithosphere and tectonic plates, although challenges still remain in picking out this boundary versus other structures within the lithosphere. [1]: /lookup/doi/10.1126/science.1169499 [2]: /lookup/doi/10.1126/science.1169754
Hepatitis C virus infection induces autocrine interferon signaling by human liver endothelial cells and release of exosomes, which inhibits viral replication

Background & Aims Liver sinusoidal endothelial cells (LSECs) make up a large proportion of the nonparenchymal cells in the liver. LSECs are involved in induction of immune tolerance, but little is known about their functions during hepatitis C virus (HCV) infection. Methods Primary human LSECs (HLSECs) and immortalized liver endothelial cells (TMNK-1) were exposed to various forms of HCV, including full-length transmitted/founder virus, sucrose-purified Japanese fulminant hepatitis-1 (JFH-1), a virus encoding a luciferase reporter, and the HCV-specific pathogen-associated molecular pattern molecules. Cells were analyzed by confocal immunofluorescence, immunohistochemical, and polymerase chain reaction assays. Results HLSECs internalized HCV, independent of cell–cell contacts; HCV RNA was translated but not replicated. Through pattern recognition receptors (Toll-like receptor 7 and retinoic acid–inducible gene 1), HCV RNA induced consistent and broad transcription of multiple interferons (IFNs); supernatants from primary HLSECs transfected with HCV-specific pathogen-associated molecular pattern molecules increased induction of IFNs and IFN-stimulated genes in HLSECs. Recombinant type I and type III IFNs strongly up-regulated HLSEC transcription of IFN λ3 (IFNL3) and viperin (RSAD2), which inhibit replication of HCV. Compared with CD8 + T cells, HLSECs suppressed HCV replication within Huh7.5.1 cells, also inducing IFN-stimulated genes in co-culture. Conditioned media from IFN-stimulated HLSECs induced expression of antiviral genes by uninfected primary human hepatocytes. Exosomes, derived from HLSECs after stimulation with either type I or type III IFNs, controlled HCV replication in a dose-dependent manner. Conclusions Cultured HLSECs produce factors that mediate immunity against HCV. HLSECs induce self-amplifying IFN-mediated responses and release of exosomes with antiviral activity.
Consumer perceptions of price, value and satisfaction in the hotel industry: an exploratory study.

The hotel industry faces the difficult task of managing the temporal demand for its product. Also, the supply of rooms has outpaced the demand over the last decade. Under this competitive environment, hotels have two basic means of achieving a sustainable competitive advantage within their product markets: (1) low price or (2) high quality. This study examines the relationships between price, value and satisfaction in regard to hotel services.
MR Imaging of the Prostate Gland

This article discusses MR imaging of the normal prostate and of disease conditions of the prostate including prostatitis, cystic lesions, amyloidosis, calculi, hematospermia, benign prostatic hyperplasia, and malignancy.
Reliability and Validity of NINCDS-ADRDA Criteria for Alzheimer's Disease: The National Institute of Mental Health Genetics Initiative

Objective: To assess interrater reliability and validity of NINCDS-ADRDA (National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association) criteria for Alzheimer's disease (AD). Design: A multisite reliability and validity study in which clinicians from each site diagnosed 60 case summaries yielding a preconsensus estimate of reliability and validity. A consensus conference was conducted for each disagreement, leading to a postconsensus estimate of validity. The criterion standard was a diagnosis of AD by autopsy. Setting: Three academic medical centers. Subjects: A convenience sample of 60 detailed case summaries, 40 with AD and 20 with other dementing disorders. Main Outcome Measures: The κ coefficient, sensitivity, and specificity. Results: The κ coefficient for preconsensus agreement on a diagnosis of probable or possible AD vs non-AD was 0.51; the sensitivity of a diagnosis of probable or possible AD for a pathological diagnosis of AD was 0.81, and the specificity was 0.73. The postconsensus sensitivity was 0.83, and the specificity was 0.84. Conclusions: The results support the reliability and validity of NINCDS-ADRDA criteria and show that the consensus process may improve diagnostic accuracy. The cases are reviewed with a focus on the sources of diagnostic disagreements and errors and possible changes that might improve the accuracy of the criteria.
Fast PGAS Implementation of Distributed Graph Algorithms

Due to the memory intensive workload and the erratic access pattern, irregular graph algorithms are notoriously hard to implement and optimize for high performance on distributed-memory systems. Although the PGAS paradigm proposed recently improves ease of programming, no high performance PGAS implementation of large-scale graph analysis is known. We present the first fast PGAS implementation of graph algorithms for the connected components and minimum spanning tree problems. By improving memory access locality, compared with the naive implementation, our implementation exhibits much better communication efficiency and cache performance on a cluster of SMPs. With additional algorithmic and PGASspecific optimizations, our implementation achieves significant speedups over both the best sequential implementation and the best single-node SMP implementation for large, sparse graphs with more than a billion edges.
Numerical and Experimental Research on a Podded Propulsor

This paper presents methodologies and some results of a numerical and experimental program to evaluate the effects of static azimuthing conditions on the propulsive characteristics of a puller podded propulsor in open water. In the experimental effort, the model propulsor was instrumented to measure thrust, torque and rotational speed of the propeller, and three orthogonal forces and moments, and azimuthing angle of the pod. The experimental results included the bare propeller (ahead only) and the combined propeller and pod over a range of advance coefficients at various static azimuthing angles in the range of −180° to 180°.A complementary numerical study is being carried out to predict the hydrodynamic forces of podded propulsor in static azimuthing conditions. A Reynolds-Averaged Navier Stokes solver is used to predict the propulsive performance of the bare propeller as well as the podded propulsor system. The thrust and torque for the bare propeller were compared to the corresponding measurements. The propeller thrust and torque as well as the loads on the pod in straight-ahead condition and at static azimuthing angles were then compared with the measurements. Preliminary analysis demonstrates that the RANS solver could predict the performance coefficients of the bare propeller as well as the podded propulsor in straight-ahead and static azimuthing angles in puller configurations.Copyright © 2014 by ASME
Health-Care Workers and HIV: Policy Choice in a Federal System

In 1991, the Centers for Disease Control (CDC) announced that a health-care worker (HCW) had apparently transmitted the virus that causes the Acquired Immune Deficiency Syndrome (AIDS) to patients whileproviding them routine medical treatment. This article examines the policy choices made based on this case. It begins by reviewing thefederal system for making these policies. The conflicting public and professional policy recommendations are then summarized. Next, aframeworkfor policy choice in a federal system is outlined and federal and state choices are described. The final section suggests some implications of these choices for American federalism.
Ultrastructure of the extensively developed nuchal organs of Laonice bahusiensis (Annelida: Canalipalpata: Spionidae)

The nuchal organs of annelid Laonice bahusiensis (Spionidae) from northern Europe have been studied using scanning and transmission electron microscopy. L. bahusiensis is the first spionid species in which extensively developed, continuous nuchal organs are described. The nuchal organs of this genus are the longest known among polychaete annelids. They consist of paired double bands extending from the prostomium on a mid-dorsal caruncle for about 24–30 setigers. Their microanatomy corresponds to the general structural plan of nuchal organs: there are ciliated supporting cells and bipolar sensory cells with sensory cilia traversing an olfactory chamber. The organs are overlaid by a secondary paving-stone-like cover and innervated by one pair of longitudinally elongated nuchal nerves. These findings clearly favor the hypothesis that the paired, extensively developed ciliated structures found in some Spionidae are homologous with the prostomial nuchal organs characteristic of polychaete annelids. J. Morphol. 2010. © 2009 Wiley-Liss, Inc.
Imaging of articular pathology: MRI, CT, arthrography

The purpose of this review article is to present the advantages and limitations of magnetic resonance imaging (MRI), computed tomography (CT) and arthrography for evaluating articular pathology. Techniques, patient selection, indications and contraindications for each modality are reviewed. MRI provides superior soft tissue contrast and image plane selection, making it the ideal technique for most articular abnormalities. However, obese patients and patients with certain electrical or metallic implants cannot be examined with MRI. CT provides superior detail for fine cortical bone and subtle calcifications, but lacks the soft tissue contrast provided by MRI. Arthrography is an invasive technique with minimal risk of allergy to contrast material or infection. This technique permits accurate measurement of capsular volume, allows for fluid aspiration for laboratory studies and permits injection of anesthetic and/or steroid compounds for purposes of treatment or confirming the site of the patient's pain. Magnetic resonance imaging, computed tomography and arthrography are useful techniques for evaluating articular pathology. Careful review of the clinical symptoms and patient's condition is necessary to select the most appropriate technique. Clin. Anat. 10:1–13, 1997 © 1997 Wiley-Liss, Inc.
Cost Management and Value Creation

The value of a company is a function of many variables. Costs are of special importance since managers can influence costs. Success at cost management has a phenomenal effect on value because of the relationships between costs, business risk, financial risk, and valuation. These relationships are non‐linear. Consequently, success in cost management yields amplified benefits in terms of value creation. In a counter sense, shortcomings in cost management result in an intensified eradication of value. Last, improved profits derived from cost management are “higher quality” increments to profits. Interestingly, the same non‐linear phenomenon holds: an increment to profits that results from costs management will have a greater addition to company value than an equal increment in profits that results from higher sales or higher sales price per unit. These reasons attest to the importance of attention to costs in value creation. Focuses on benefits of cost management in terms of: the reduction of business risk; ...
Level structure of Ge 67 and its implications for the general structure of nuclei in the 1 f − 2 p shell

From the results of prompt and $\ensuremath{\beta}$-delayed $\ensuremath{\gamma}$-ray singles and $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence measurements, twenty-four excited states and forty-six gamma transitions are identified in the level scheme of $^{67}\mathrm{Ge}$. Angular distributions and directional correlations of prompt $^{67}\mathrm{Ge}$ gamma rays have been measured to obtain the spins of the $^{67}\mathrm{Ge}$ ground state and excited states at 18.2, 122.7, 243.6, 711.3, and 1019.9 keV. Parities are assigned to the first five states on the basis of $\mathrm{fp}$ shell systematics and observed $^{67}\mathrm{Ge}$ gamma-ray branching ratios. The 752-keV excitation energy of the first ${\frac{9}{2}}^{+}$ level in $^{67}\mathrm{Ge}$ is determined from an excitation function for the $^{64}\mathrm{Zn}(\ensuremath{\alpha}, \mathrm{n}\ensuremath{\gamma})^{67}\mathrm{Ge}$ reaction. The angular distribution and correlation measurements also provide $\frac{E2}{M1}$ mixing ratios for the 104.4, 120.8, 122.7, 243.6, 589.0, and 897.5 keV $^{67}\mathrm{Ge}$ gamma rays. The level scheme of $^{67}\mathrm{Ge}$ and the corresponding schemes for $^{63,65}\mathrm{Ni}$, $^{65,67}\mathrm{Zn}$, and $^{69}\mathrm{Ge}$ are observed to have strong similarities at low excitation. Systematic trends in $E2$ transition rates are interpreted in the context of shell and collective features of the nuclei. It is found that models based on a single particle coupled to a vibrational or deformed core do not explain the observed systematics, and are an inaccurate representation of these nuclei. The systematics do agree with a many-nucleon shell model emphasizing the short-range pairing interaction and configuration mixing for the valence neutrons.NUCLEAR REACTIONS $^{64}\mathrm{Zn}(\ensuremath{\alpha}, \mathrm{n}\ensuremath{\gamma})$, $^{63}\mathrm{Cu}(^{6}\mathrm{Li}, 2\mathrm{n}\ensuremath{\gamma})$, $^{58}\mathrm{Ni}(^{14}\mathrm{N}, \ensuremath{\alpha}\mathrm{n})$; $^{67}\mathrm{Ge}$ level scheme, $E\ensuremath{\gamma}$, $\ensuremath{\gamma}(\ensuremath{\theta})$, $\ensuremath{\gamma}\ensuremath{\gamma}(\ensuremath{\theta})$, $\ensuremath{\delta}(\frac{E2}{M1})$, ${J}^{\ensuremath{\pi}}$. Directional correlations with an oriented source. Ge(Li) detectors, enriched targets. Nuclear systematics, nuclear deformation.
Race, Class, Gender and Community College Persistence Among African American Women

This inquiry is an exploration of the educational trajectories of African American women community college students. We compare the persistence of African American women to African American men and to all women college students using the 1996/2001 Beginning Postsecondary Students Longitudinal Survey and the 1993/2003 Baccalaureate and Beyond Longitudinal Survey. We find that the propensity of African American women to enroll notwithstanding, African American women attending community colleges are less likely to graduate than their African American male peers and than their female peers. However, we also find that African American women who start at community colleges and complete a Bachelor degree are similar to African American men and all women who pursue graduate degrees. This implies that greater attention to the trajectories of African American women through the community college is warranted as the majority of those entering postsecondary education do so at the community college. Assisting these wom...
CD4+ CD56+ hematodermic/plasmacytoid dendritic cell tumor with response to pralatrexate

The CD4 + CD56 + hematodermic/plasmacytoid dendritic cell tumor is a rare, highly aggressive, systemic neoplasm for which effective therapies have not yet been established. These tumors express CD4, CD56, CD123, and T-cell leukemia/lymphoma (TCL)-1 and are clinically characterized by cutaneous involvement with spread to bone marrow and blood, and poor prognosis with current chemotherapy regimens. We describe a Caucasian woman who presented with plasmacytoid dendritic cell tumor, but an absence of systemic symptoms. Clinically, multiple cutaneous lesions were brown to violaceous firm nodules on the face, arms, and trunk. The patient underwent two courses of cyclophosphamide, Adriamycin, vincristine, and prednisone chemotherapy but relapsed quickly. The investigational agent, pralatrexate (30 mg/m 2 ) was given weekly with vitamin B12 and folic acid and resulted in remarkable clinical response with regression of skin tumors. Our observation highlights pralatrexate as a promising therapeutic option for hematodermic/plasmacytoid dendritic cell lymphoma/leukemias.
Microscopic evaluation of the effects of some vital staining agents on growing bone in rabbits.

Various doses of alizarin red S, trypan blue, chlortetracycline and45Ca were injected into young male New Zealand white rabbits. The influence of these agents on bone growth was studied at the microscopic level by comparison with vital staining by lead acetate.
In Vitro Dermal Penetration of 4-Chloro-3-Methylphenol from Commercial Metal Working Fluid and Aqueous Vehicles

The biocide 4-chloro-3-methylphenol (CMP, CAS number 59-50-7) is a common additive to metal-working fluids (MWF) and building materials. National Institute for Occupational Safety and Health (NIOSH) researchers previously identified and quantified CMP in a commercial water-soluble MWF, TRIM VX, and demonstrated irritancy and sensitization potential of both TRIM VX and CMP alone after dermal exposure in a murine model. In the current study, the in vitro human epidermal permeability of CMP contained in a working dilution of TRIM VX (20% in water) was evaluated and, for comparison, permeability from an aqueous buffer was also assessed. CMP penetration was also measured from transient exposures to 20% TRIM VX. To address differences in penetration rates from 20% TRIM VX and from buffer, the role of thermodynamic activity of CMP in the 2 vehicles on dermal penetration was investigated. Static headspace gas chromatography was used to measure vapor pressures and infer fractional thermodynamic activities of CMP i...
A New Generator Differential Relay

“RELAYS have been available for years capable of providing selective high-speed protection if — and it is a big IF — the intelligence transmitted to the relay closely approximates the truth.” This statement, recently made by a protection engineer, is a true statement, the import of which is not always fully recognized.
Differential proteomic response to heat stress in thermal Agrostis scabra and heat-sensitive Agrostis stolonifera

Knowledge of heat-responsive proteins is critical for further understanding of the molecular mechanisms of heat tolerance. The objective of this study was to compare proteins differentially expressed in two C(3) grass species contrasting in heat tolerance, heat-tolerant thermal Agrostis scabra and heat-sensitive Agrostis stolonifera L., and to identify heat-responsive proteins for short- and long-term responses. Plants were exposed to 20/15 degrees C (day/night, control) or 40/35 degrees C (day/night, heat stress) in growth chambers. Leaves were harvested at 2 and 10 days after temperature treatment. Proteins were extracted and separated by fluorescence difference gel electrophoresis (DIGE). Thermal A. scabra had superior heat tolerance than A. stolonifera, as indicated by the maintenance of higher chlorophyll content and photochemical efficiency under heat stress. The two-dimensional difference electrophoresis detected 68 heat-responsive proteins in the two species. Thermal A. scabra had more protein spots either down- or up-regulated at 2 days of heat stress, but fewer protein spots were altered at 10 days of heat stress compared with A. stolonifera. Many protein spots exhibited transient down-regulation in thermal A. scabra (only at 2 days of heat treatment), whereas down-regulation of many proteins was also found at 10 days of heat treatment in A. stolonifera, which suggested that protein metabolism in thermal A. scabra might acclimate to heat stress more rapidly than those in A. stolonifera. The sequences of 56 differentially expressed protein spots were identified using mass spectrometry. The results suggest that the maintenance or less severe down-regulation of proteins during long-term (10 days) heat stress may contribute to the superior heat tolerance in thermal A. scabra, including those involved in photosynthesis [RuBisCo, RuBisCo activase, chloroplastic glyceraldehydes-3-phosphate dehydrogenase (GAPDH), chloroplastic aldolase, oxygen-evolving complex, photosystem I subunits], dark respiration (cytosolic GAPDH, cytoplasmic aldolase, malate dehydrogenase, hydroxypyruvate reductase, sedoheptulose-1,7-bisphosphatase), photorespiration [(hydroxypyruvate reductase, alanine aminotransferase (AlaAT), hydroxymethyltransferase (SHMT), glycine decarboxylase (GDC)], as well as heat and oxidative stress protection [heat shock cognate (HSC) 70 and FtsH-like protein].
Thermodynamics of RNA Folding in a Conserved Ribosomal RNA Domain

Abstract A small, 58 nt domain of the large subunit ribosomal RNA (Escherichia coli sequence 1051 to 1108) is a highly conserved junction of three helices whose secondary structure has been established by phylogenetic comparisons. To detect any contributions of additional tertiary interactions, the thermal denaturation of the rRNA domain was followed by either UV hyperchromicity or calorimetry in buffers containing a wide range of Mg2+ concentrations. Several smaller fragments corresponding to two different hairpin stem-loop structures within the domain were also synthesized and melted for comparison with the larger molecule. A model of the secondary structure unfolding was devised, based on measured enthalpies and melting temperatures of the component hairpins and tabulated parameters of base-pair stacking and loop closure. The model closely simulates the observed melting data when three additional factors are included: two parameters to account for coaxial stackings within a junction of helices, and a set of undefined "tertiary" interactions that unfolds before the secondary structure and is preferentially stabilized by Mg2+. A critical feature of this model is a conserved pair, U1082/A1086, that is within the junction loop and hypothesized to stack with an adjacent helix. The model correctly predicts the effects of disrupting this pair in a U1086 sequence variant. Although the set of "tertiary" interactions contributes a significant fraction of the RNA unfolding enthalpy (δH ≈25 kcal/mol, out of 180 kcal/mol total), its overall stability is marginal at 37°C.
Mass‐independent isotope effects and their use in understanding natural processes

In 1983, Thiemens and Heidenreich (Science 219, 1073) reported the discovery of a mass-independent isotope process in oxygen. Subsequently, mass-independent isotopic compositions were observed in meteorites, atmospheric O 2 , CO 2 , O 3 , H 2 O 2 , CO, N 2 O, and aerosol sulfate and nitrate. In addition, solid samples from the Namibian Desert, Antarctic dry valleys, Miocene volcanic ash, and Death Valley varnishes all possess mass-independent isotopic compositions that have permitted new scientific insights to be obtained. Sulfur mass-independent isotopic anomalies in Precambrian samples have provided a completely new mechanism to track atmospheric O 2 levels and the evolution of life from ∼3.9 to 2.2 × 10 9 years ago. Measurements of mass-independent isotopic compositions in Martian meteoritic sulfates and carbonates have also provided new information on Martian atmosphere-regolith interactions and history. In sum, the use of mass-independent isotopic compositions has advanced a wide range of geo- and cosmo-chemical frontiers. In addition, these newly discovered effects have provided a new means to probe the chemical physics of molecular transition state theory.
Tubulin folding cofactors as GTPase-activating proteins. GTP hydrolysis and the assembly of the alpha/beta-tubulin heterodimer.

In vivo, many proteins must interact with molecular chaperones to attain their native conformation. In the case of tubulin, newly synthesized α- and β-subunits are partially folded by cytosolic chaperonin, a double-toroidal ATPase with homologs in all kingdoms of life and in most cellular compartments. α- and β-tubulin folding intermediates are then brought together by tubulin-specific chaperone proteins (named cofactors A–E) in a cofactor-containing supercomplex with GTPase activity. Here we show that tubulin subunit exchange can only occur by passage through this supercomplex, thus defining it as a dimer-making machine. We also show that hydrolysis of GTP by β-tubulin in the supercomplex acts as a switch for the release of native tubulin heterodimer. In this folding reaction and in the related reaction of tubulin-folding cofactors with native tubulin, the cofactors behave as GTPase-activating proteins, stimulating the GTP-binding protein β-tubulin to hydrolyze its GTP.
Effect of Aza-Substituted Nucleotides on the Starve-Refeed Response of Rats

SummaryRat liver glucose 6-phosphate dehydrogenase (G6PD) and malic enzyme (ME) activities were increased by starvation-refeeding to levels above those found in rats fed ad libitum. The increases in enzyme activities above ad libitum-fed levels were prevented by 8-azaguanine and 6-aza-uridine, but not by 2-azauridine. Blood insulin levels were not affected at the time studied. Two aza analogs, 8-azaadenine and 5-azacytidine, proved to be too toxic in this type of studies. Since 8-azahypoxanthine, 8-azaxanthine and 5-azauracil were neither effective in preventing the enzyme overshoot, nor toxic to the animals, it was concluded that the toxicity to the animals of 8-azaadenine and 5-azacytidine is due to the compounds themselves rather than to their breakdown products.The author wishes to thank the following people: C. D. Berdanier, P. B. Moser, and S. K. Diachenko who collaborated with the author on experiment 1; O. E. Michaelis, IV and C. S. Nace for technical assistance; and R. F. Doherty and R. Sanchez (...