cssi/SciSciGPT-SciSciNet huggingface dataset:
Layer intermixing and related long-term instability in heavily carbon-doped AlGaAs superlattices

Superlattices (SLs) of Alo.3Gao.7As/GaAs grown by metalorganic chemical vapor deposition and heavily doped with carbon using CClp4 were annealed for 24 h at 825° C under a variety of ambient and surface encapsulation conditions. Photoluminescence atT = 1.7 K has been employed to determine approximate Al-Ga interdiffusion coefficients (D Ai-Ga) for different annealing conditions. For all encapsulants studiedD Al-Ga increases with increasing As4 pressure in the annealing ampoule. This result disagrees with trends reported for Mg-doped crystals, and with predictions of the charged point-defect (Fermilevel) model. The Si3N4 cap provides the most effecitve surface sealing against ambientstimulated layer interdiffusion (D Al-Ga ≈ 1.5-3.9 x 10-19 cm2/sec). The most extensive layer intermixing has occurred for an uncapped SL annealed under As-rich ambient (D Al-Ga ≈ 3.3 x 10-18 cm2/sec). These values are up to ~40 times greater than those previously reported for nominally undoped AIGaAs/GaAs SLs, implying that theC As doping slightly enhances layer intermixing, but significantly less than predicted by the Fermi-level effect. The discrepancies between the experimental data and the model are discussed. Pronounced changes in the optical properties of the annealed SLs with storage time at room temperature are also reported. These changes may indicate a degraded thermal stability of the annealed crystals due to high-temperature-induced lattice defects. A possibly related effect of the systematic failure to fabricate buried heterostructure quantum well lasers via impurity-induced layer disordering in similarly doped AIGaAs/GaAs crystals is discussed.
Community development corporations as neighborhood advocates: a study of the political activism of nonprofit developers

A number of arguments exist that suggest that community development corporations (CDCs) represent an apolitical, technocratic, and non-democratic arm of the neighborhood movement. This paper evaluates that,argument by examining national level studies, and using Minneapolis and St. Paul as case studies. The findings reveal that CDCs retain a high level of political activism primarily through the creation of new institutions, citywide coalition bodies, to carry out their political agenda. The findings also suggest that government influence over CDCs is greater in the area of program strategies than political activity.
Protein Kinase Cα-RhoA Cross-talk in CCL2-induced Alterations in Brain Endothelial Permeability

Monocyte chemoattractant protein-1 (MCP-1 or CCL2) regulates blood-brain barrier permeability by inducing morphological and biochemical alterations in the tight junction (TJ) complex between brain endothelial cells. The present study used cultured brain endothelial cells to examine the signaling networks involved in the redistribution of TJ proteins (occludin, ZO-1, ZO-2, claudin-5) by CCL2. The CCL2-induced alterations in the brain endothelial barrier were associated with de novo Ser/Thr phosphorylation of occludin, ZO-1, ZO-2, and claudin-5. The phosphorylated TJ proteins were redistributed/localized in Triton X-100-soluble as well as Triton X-100-insoluble cell fractions. Two protein kinase C (PKC) isoforms, PKCα and PKCζ, had a significant impact on this event. Inhibition of their activity using dominant negative mutants PKCα-DN and PKCζ-DN diminished CCL2 effects on brain endothelial permeability. Previous data indicate that Rho/Rho kinase signaling is involved in CCL2 regulation of brain endothelial permeability. The interactions between the PKC and Rho/Rho kinase pathways were therefore examined. Rho, PKCα, and PKCζ activities were knocked down using dominant negative mutants (T17Rho, PKCα-DN, and PKCζ-DN, respectively). PKCα and Rho, but not PKCζ and Rho, interacted at the level of Rho, with PKCα being a downstream target for Rho. Double transfection experiments using dominant negative mutants confirmed that this interaction is critical for CCL2-induced redistribution of TJ proteins. Collectively these data suggest for the first time that CCL2 induces brain endothelial hyperpermeability via Rho/PKCα signal pathway interactions.
Modification of β-adrenergic receptor binding in rat brain following thyroxine administration

Abstract The effect of repeated administration of thyroxine on β-adrenergic receptor binding was studied in several brain regions in the rat using [ 3 H]dihydroalprenolol as a ligand. Thyroxine treatment resulted in an increased density of β-adrenergic receptors in the cerebral cortex while a decreased binding was found in subcortical tissue representing the thalamus, striatum and parts of the limbic system. There was no change in binding in the cerebellum or in the brainstem. The results indicate that thyroxine may regulate β-adrenergic receptors in certain brain areas.
Endocrine regulation of the elasmobranch reproductive tract

Although the rich variety of reproductive tract adaptations in elasmobranchs has been well documented and involves many variants associated with oviparity and extensive evolution of viviparity in the group, little is known of the hormone dependence of reproductive tract development, differentiation, and function in the adult. In this paper, we present a brief review of some of our observations on the subject made over the past 15 years in the context of earlier observations. In total, despite the paucity of information, the observations suggest that hormonal mechanisms of reproductive tract regulation, considered until recently to be the priority of mammals, have been in place since the era of very early vertebrate evolution, 400 million years before present. These reinforce the view that the endocrine regulatory mechanisms of reproduction in elasmobranchs may serve as models for more highly evolved mammalian species including the human. Indeed, the enormous variety of reproductive tract adaptations in elasmobranchs foreshadows those subsequently evolved in mammals, and because of transitional stages provide needed insight into process which is not possible in the study of mammals alone. © 1993 Wiley-Liss, Inc.
Local behavior and global existence of positive solutions of auλ⩽−Δu⩽uλ

We study the behavior near the origin of C2 positive solutions u(x) of (∗)auλ⩽−Δu⩽uλ in a punctured neighborhood of the origin in Rn (n>2) where the constants λ and a satisfy nn−2<λ<n+2n−2 and 0<a<1. We also study the existence of C2 positive solutions of (∗) in Rn. In both cases we show that changing a from one value in the open interval (0,1) to another value in (0,1) can have a dramatic effect.
Structural features of cell-wall polysaccharides of the carrot Daucus carota

Abstract Cell-wall material was isolated from the alcohol-insoluble residue of carrot by treatment with Pronase, phenol—acetic acid—water, and aqueous 90% methyl sulphoxide. Some pectic material was solubilised, but the major component was a highly esterified, acidic arabinogalactan. The purified cell-wall material, which contained ∼1% of protein, was sequentially extracted with water at 80°, ammonium oxalate at 80°, and m and 4 m KOH at 20°, to leave a residue of α-cellulose, which contained some pectic material. From the hot-water-soluble fraction, a major pectic polymer was isolated by anion-exchange chromatography. Methylation analysis showed that it was a rhamnogalacturonan, probably having highly branched arabinan and slightly branched galactan side-chains linked to O-4 of rhamnopyranosyl residues. An unusual feature of this pectic polymer is that it contained a small but significant proportion of 1,4-linked xylopyranosyl residues. From the alkali-soluble fractions, a range of pectic polymers associated with various amounts of xylans and possibly xyloglucans was isolated. The main linkages present in these complexes were 1,4-linked galactopyranosyluronic acid, 1,4-linked galactopyranosyl, and 1,5-linked arabinofuranosyl residues, terminal arabinofuranosyl and galactopyranosyl groups, and, in some fractions, 1,4-linked xylopyranosyl residues. The possible association of some of these polymers with proteins and phenolics is discussed.
Life Course Patterns of Career-Prioritizing Decisions and Occupational Attainment in Dual-Earner Couples:

Couples' long-term pattern of favoring one spouse's career in major decisions is thought to affect occupational trajectories, but current research has looked only at short-term effects of single decisions. This article applies a new technique, the interpolated curves approach, to represent and compare life course patterns of major career-prioritizing decisions, using in-depth data from 51 couples. Five clusters of career hierarchy patterns are identified; the patterns predict income better than summary measures of career hierarchy, including average individual career gains to decisions and self-reported career priority. Findings are significant for wives, and are similar but weaker for husbands.
The Social Ecology of Cervical Cancer: The Challenges to Pap Smear Screening

Cervical cancer is a preventable disease. The risk factors for the development of cervical cancer include both biologic factors and social factors. In the United States, the leading risk factor for the development of cervical cancer is not having a Pap smear for five years prior to the diagnosis of cancer. In low and middle income countries, cervical cancer incidence and mortality are directly related to the lack of both screening programs and cancer treatment facilities. This paper examines the social ecology of cervical cancer. The literature is reviewed on social and cultural barriers to access to health care and its effect of cervical cancer rates and outcomes.
Clinical speech considerations in prosthodontics: perspectives of the prosthodontist and speech pathologist.

Abstract Speech is a dynamic process with which prosthodontists are involved. Should a denture patient manifest difficulty in speech, it is crucial to differentiate defects which are denture-related from those produced by other coexistent conditions. Seven dimensions basic to speech are discussed: (1) respiration, (2) phonation, (3) resonance, (4) speech articulation, (5) audition, (6) neurologic integration, and (7) emotional behavior. Clinical aspects of these factors as they relate to prosthodontics are described. For speech purposes, static, positional concepts of incisor relationships and denture contours should not be emphasized at the expense of dynamic considerations. Each patient's condition should be evaluated to assure that the denture can provide an optimal environment for the rapid, coordinated muscle movements requisite for acceptable speech.
Behavioral Treatment of Childhood Gender Disorders A Conceptual and Empirical Critique

Social learning techniques recently have been applied to the problem of childhood gender disorders. This diagnosis has been applied mostly to young boys who show pronounced degrees of "feminine" behavior and interests, who avoid activities stereotypically associated with their gender, and who express the desire to become girls. A conceptual and empirical critique is offered of this small but developing treatment literature. Conceptual difficulties attributable to the mixing of psychoanalytic and behavioral frames of references and to the use of gender role stereotypes as a reference point for defining abnormal behavior make the interpretation of the reported treatment successes problematic. Much of the confusion in this research area could be dispelled if systematic attention were paid to what the so-called "feminine" behavior means to the boy. This could be achiieved by means of a functional analysis of the relationships between the boy's cognitions and behaviors and the contexts in which they occur.
College Students as Helpful Bystanders Against Sexual Violence: Gender, Race, and Year in College Moderate the Impact of Perceived Peer Norms

Prior research documents that perceived peer norms are related to bystanders’ intentions and intervention behaviors in the context of sexual violence. Given the popularity of bystander intervention programming, it is important to know if variables like gender, race, or year in college impact intervention attitudes/behaviors or interact with perceived peer norms. Also relatively unexplored is the question of missed opportunities for intervention. For our final sample of 232 college students (66% female, 36% Black), screened by age, race, and missing data from an initial pool of 315 respondents, perceived peer norms supporting intervention positively predicted willingness to intervene against sexual violence (bystander intentions) but did not independently predict bystander behaviors or missed opportunities for intervention. Although women reported greater bystander intentions than did men, and Black participants reported more bystander behaviors than did White participants, gender, race, and year in colleg...
sNICh: efficient last hop networking in the data center

Virtualization has fundamentally changed the data center network. The last hop of the network is no longer handled by a physical network switch, but rather is typically performed in software inside the server to switch among virtual machines hosted by that server.In this paper, we present the concept of a sNICh, which is a combination of a network interface card and switching accelerator for modern virtualized servers. The sNICh architecture exploits the proximity of the switching accelerator to the server by carefully dividing the network switching tasks between them. This division enables the sNICh to address the resource intensiveness of exclusively software-based approaches and the scalability limits of exclusively hardware-based approaches. Essentially, the sNICh hardware performs basic flow-based switching and the sNICh software handles flow setup based on packet filtering rules. The sNICh also minimizes I/O bus bandwidth utilization by transferring, whenever possible, inter-virtual machine traffic within the main memory.We also present a preliminary evaluation of this architecture using software emulation. We compare the performance of the sNICh with two existing software solutions in Xen, the Linux bridge and Open vSwitch. Our results show that the sNICh outperforms both of these existing solutions and also exhibits better scalability.
Convergence and Stability of Iteratively Re-weighted Least Squares Algorithms

In this paper, we study the theoretical properties of iteratively re-weighted least squares (IRLS) algorithms and their utility in sparse signal recovery in the presence of noise. We demonstrate a one-to-one correspondence between the IRLS algorithms and a class of Expectation-Maximization (EM) algorithms for constrained maximum likelihood estimation under a Gaussian scale mixture (GSM) distribution. The EM formalism, as well as the connection to GSMs, allow us to establish that the IRLS algorithms minimize smooth versions of the lν `norms', for . We leverage EM theory to show that the limit points of the sequence of IRLS iterates are stationary points of the smooth lν “norm” minimization problem on the constraint set. We employ techniques from Compressive Sampling (CS) theory to show that the IRLS algorithm is stable, if the limit point of the iterates coincides with the global minimizer. We further characterize the convergence rate of the IRLS algorithm, which implies global linear convergence for ν = 1 and local super-linear convergence for . We demonstrate our results via simulation experiments. The simplicity of IRLS, along with the theoretical guarantees provided in this contribution, make a compelling case for its adoption as a standard tool for sparse signal recovery.
Protein adsorption and smooth muscle cell adhesion on biodegradable agmatine-modified poly(propylene fumarate-co-ethylene glycol) hydrogels.

We synthesized positively charged biodegradable hydrogels from poly(propylene fumarate-co-ethylene glycol) block copolymer and agmatine-modified poly(ethylene glycol)-tethered fumarate by radical crosslinking, and investigated the effect of the guanidino group of agmatine on vascular smooth muscle cell adhesion and protein adsorption to the hydrogels. In the presence of serum, the number of adherent smooth muscle cells per unit surface area increased dose-dependently from 15 to 75% of the initial seeding density at 20 h as the initial agmatine-modified monomer content increased from 0 to 200 mg/g. Cell spreading also depended on the initial monomer content. In the absence of serum, the number of adherent cells per unit surface area increased slightly from 10 to 17% of the initial seeding density as the initial monomer content increased from 0 to 200 mg/g. Cell adhesion increased significantly by adding exogenous vitronectin to serum-free medium, whereas exogenous fibronectin addition did not enhance cell adhesion. The enzyme-linked immunosorbent assay of fibronectin and vitronectin adsorbed onto the hydrogels revealed that the incorporation of positive charges into the hydrogels enhanced vitronectin, but not fibronectin, adsorption significantly. These results suggest that the guanidino group of agmatine enhanced cell adhesion by promoting the adsorption of serum components, and vitronectin may be one of the components.
A Simple Analytical Tool for Legged Robot Design

Although legged locomotion is better at tackling complicated terrains compared with wheeled locomotion, legged robots are rare, in part, because of the lack of simple design tools. The dynamics governing legged locomotion are generally nonlinear and hybrid (piecewise-continuous) and so require numerical simulation for analysis and are not easily applied to robot designs. During the past decade, a few approximated analytical solutions of Spring-Loaded Inverted Pendulum (SLIP), a canonical model in legged locomotion, have been developed. However, SLIP is energy conserving and cannot predict the dynamical stability of real-world legged locomotion. To develop new analytical tools for legged robot designs, we first analytically solved SLIP in a new way. Then based on SLIP solution, we developed an analytical solution of a hip-actuated Spring-Loaded Inverted Pendulum (hip-actuated-SLIP) model, which is more biologically relevant and stable than the canonical energy conserving SLIP model. The analytical approximations offered here for SLIP and the hip actuated-SLIP solutions compare well with the numerical simulations of each. The analytical solutions presented here are simpler in form than those resulting from existing analytical approximations. The analytical solutions of SLIP and the hip actuated-SLIP can be used as tools for robot design or for generating biological hypotheses.Copyright © 2012 by ASME
Carbon Support Effects on Bimetallic Pt−Ru Nanoparticles Formed from Molecular Precursors

We describe the preparation, structural characterization, and support interactions experienced by two different compositions of Pt−Ru nanoparticles supported on several carbons (carbon black, fullerene soot, and desulfurized carbon black). The bimetallic nanoparticles, obtained by reduction of the neutral molecular precursors PtRu5C(CO)16 and Pt2Ru4(CO)18 (the latter of which lacks a central “stabilizing” carbide core) at elevated temperatures in a hydrogen atmosphere, show a structural homology, exhibiting exceptionally narrow size and compositional distributions. A detailed structural picture of the nanoparticles has been deduced on the basis of in-situ extended X-ray absorption fine structure (EXAFS), scanning transmission electron microscopy (STEM), energy-dispersive X-ray analysis (EDX), and X-ray absorption near edge structure (XANES). These techniques reveal that the bimetallic nanoparticles have Pt/Ru compositions of 1:5 and 2:4, respectively, and average diameters lying between 1.0 and 1.5 nm. Th...
Central serotonergic receptors: Evidence for heterogeneity and characterization by ligand-binding

Evidence has accumulated which suggests that receptors for serotonin exist in multiple forms both in the central nervous system and the periphery. This has come from the use of a variety of techniques and a number of different tissues. In the central nervous system the ligand-binding technique has proven particularly useful for characterizing different types of serotonin receptors, and two major classes of central serotonin receptors have been proposed on the basis of studies using this procedure. The first group (5-HT1 receptors) is defined by the high-affinity binding of 3H-serotonin in the brain, and the second (5-HT2 receptors) is defined by the high-affinity binding of 3H-spiperone in the frontal cortex. The 5-HT1 sites have themselves been shown to be a heterogeneous group, and recent studies suggest that it is possible to synthesize tryptamine analogues which can discriminate between the different types of 5-HT1 receptors. Such studies suggest the possibility of designing new selective serotonin agonists and antagonists for the study of the effects of specific receptor subtypes on behavioral and physiological activities.
In vitro correlate of immunity in an animal model of inhalational anthrax

fA serological correlate of vaccine-induced immunity was identified in the rabbit model of inhalational anthrax. Animals were inoculated intramuscularly at 0 and 4 weeks with varying doses of Anthrax Vaccine Adsorbed (AVA) ranging from a human dose to a 1:256 dilution in phosphate-buffered saline (PBS). At 6 and 10 weeks, both the quantitative anti-protective antigen (PA) IgG ELISA and the toxin-neutralizing antibody (TNA) assays were used to measure antibody levels to PA. Rabbits were aerosol-challenged at 10 weeks with a lethal dose (84-133 LD,,) of Bacillus anthracis spores. All the rabbits that received the undiluted and 1:4 dilution of vaccine survived, whereas those receiving the higher dilutions of vaccine (1:16, 154 and 1:256) had deaths in their groups. ~esults showed that antibody levels to PA at both 6 and 10 weeks were significant (P < 0.0001) predictors of survival. Published by Elsevier Science Ltd. Keynlords: Anthrax; Baci//us anfltracis; Serological correlate
Measurement of Water Vapor Sorption by Single Biological Aerosols

Single particle levitation (SPL) is used to measure water vapor sorption and desorption from micrometer-sized particles comprised of Bacillus spores and yellow pine pollen. Water gain-loss is determined from increases-decreases in the weight-balancing levitation voltages. BET (Brunauer, Emmett, and Teller) surface area analysis of the spore water isotherms are performed and compared to values previously reported using bulk gravimetric methods. Two salient differences are found between the SPL and bulk data: (1) greater osmotic swelling is observed in the SPL data and (2) the SPL data exhibits open loop hysteresis while bulk data exhibits closed loop hysteresis. Yellow pine pollen exhibits a distinct water isotherm when compared to that of Bacillus spores.
Dopaminergic inhibition of striatal acetylcholine release after 6-hydroxydopamine

Field stimulation increased tritium efflux from rat striatal slices preincubated with [3H]choline, an index of acetylcholine release. When stimulated at low frequency (1 Hz for 2 min), nomifensine (10 microM) reduced acetylcholine release, while at high frequency (8 Hz for 1 min), sulpiride (1 microM) increased release. After 6-hydroxydopamine-induced damage to dopamine neurons, these effects were reduced but the extent of the depletion necessary to block the drug effects increased with the passage of time. Up-regulation of dopamine D-2 receptors seen at 2 months was not detected unless dopamine depletion was very large (90%). These findings indicate that dopamine, acting at the dopamine D-2 receptor, normally exerts an inhibitory influence over acetylcholine release in striatum, that after partial injury the dopaminergic influence over acetylcholine release can recover with time, and that the recovery involves processes other than changes in the number of D-2 receptors.
Simulating turbulence in complex geometries

We first review the state-of-the art in direct numerical simulation and present a new class of spectral methods on unstructured grids for handling complex-geometry domains. Subsequently, we concentrate on the classical problem of the turbulent wake behind a circular cylinder and compare the accuracy of spectral DNS versus other LES results available in the literature. We find that DNS provides consistent agreement with the experimental results, but that LES predictions are inconsistent and depend strongly on the interaction between numerical discretization and the subgrid model. We also demonstrate via a simple vorticity-based analysis of the turbulent near-wake that eddy-viscosity models are inappropriate for sudgrid modeling. In contrast, preliminary a priori tests suggest that scale-similarity models may be a good candidate. We close the paper by forecasting the use of dynamic DNS and comment on its role in simulating turbulence in complex geometries.
Characterizing pattern preserving clustering

This paper describes a new approach for clustering—pattern preserving clustering—which produces more easily interpretable and usable clusters. This approach is motivated by the following observation: while there are usually strong patterns in the data—patterns that may be key for the analysis and description of the data—these patterns are often split among different clusters by current clustering approaches. This is, perhaps, not surprising, since clustering algorithms have no built-in knowledge of these patterns and may often have goals that are in conflict with preserving patterns, e.g., minimize the distance of points to their nearest cluster centroids. In this paper, our focus is to characterize (1) the benefits of pattern preserving clustering and (2) the most effective way of performing pattern preserving clustering. To that end, we propose and evaluate two clustering algorithms, HIerarchical Clustering with pAttern Preservation (HICAP) and bisecting K-means Clustering with pAttern Preservation (K-CAP). Experimental results on document data show that HICAP can produce overlapping clusters that preserve useful patterns, but has relatively worse clustering performance than bisecting K-means with respect to the clustering evaluation criterion of entropy. By contrast, in terms of entropy, K-CAP can perform substantially better than the bisecting K-means algorithm when data sets contain clusters of widely different sizes—a common situation in the real-world. Most importantly, we also illustrate how patterns, if preserved, can aid cluster interpretation.
Layered thermal metamaterials for the directing and harvesting of conductive heat

The utility of a metamaterial, assembled from two layers of nominally isotropic materials, for thermal energy re-orientation and harvesting is examined. A study of the underlying phenomena related to heat flux manipulation, exploiting the anisotropy of the thermal conductivity tensor, is a focus. The notion of the assembled metamaterial as an effective thermal medium forms the basis for many of these investigations and will be probed. An overarching aim is to implement in such thermal metamaterials, functionalities well known from light optics, such as reflection and refraction, which in turn may yield insights on efficient thermal lensing. Consequently, the harness and dissipation of heat, which are for example, of much importance in energy conservation and improving electrical device performance, may be accomplished. The possibilities of energy harvesting, through exploiting anisotropic thermopower in the metamaterials is also examined. The review concludes with a brief survey of the outstanding issues and insights needed for further progress.
Stability analysis of flexibly connected thin-walled space frames

Abstract The elastic stability (bifurcation) response of space frames, including warping deformation and flexible (semi-rigid) connections, is considered. Calculation of the elastic stability load is based on a linear eigenvalue analysis. A parametric study of the effect of connection rigidity for a portal space frame of variable geometry subjected to gravity and various wind loads is presented to provide insight into the stability behavior of space frames.
Negation in Mandarin Chinese

This paper proposes an analysis of Mandarin Chinese negation in whichbu ‘not’ is an adverb in Spec,AuxP or Spec, VP which may occur only with unbounded aspectual situations and which must cliticize to the following element at S-structure. Evidence comes primarily from the facts that (1)bu does not normally occur with perfective aspect markers or with telic situations (such as achievements), and (2) whilebu occurs with preverbal adjuncts, it cannot cooccur with certain types of postverbal adjuncts: it is argued that postposing the latter from their base preverbal position leaves a trace which preventsbu from cliticizing, as it must. Evidence comes also from (3) the untenability of alternative analyses invoking scope or overt head movement. This analysis supports the views that morphological requirements of functional items may have important consequences for syntax and that the distribution of such items can be accounted for, in part, by ‘Affix Checking’, i.e., head movement at LF rather than in overt syntax.
MEMS deformable mirror actuators with enhanced reliability

MEMS deformable mirrors with thousands of actuators are under development for space-based operation, which require fault tolerant actuators that will not fail due to electrical overstress. We report on advances made in the development of MEMS deformable mirror actuators with enhanced reliability for space-based, high-contrast imaging instrumentation that eliminate irreversible actuator damage resulting from snap-through.
Synthesis of the covalent hydrate of the incorrectly assumed structure of aurintricarboxylic acid (ATA)

Abstract The triphenylcarbinol 6, which is the covalent hydrate of the generally accepted, but incorrect structure of aurintricarboxylic acid (ATA), has been synthesized and found to protect against the cytopathic effect of HIV-1 in CEM-V lymphocyte cell culture. The synthesis involved the first preparation of pure methylene disalicylic acid (5). The triphenylcarbinol 6 provides a novel lead, apart from (polymeric) ATA, for the development of potential anti-AIDS agents. The central carbinol oxygen of 6 did not exchange in the presence of excess oxygen-18 labelled water at room temperature even after seven days, indicating that there was no equilibration between 6 and 1 under these conditions.
How mobile is capital in developing countries

Abstract The paper develops a technique for measuring the degree of financial openness in financially-repressed economies and applies it to a large sample of developing countries. The results suggest that developing countries, in general, can be characterized as financially-open economies.
Image Placement Distortions in EPL Masks

Electron projection lithography (EPL) is a promising candidate for the next generation lithography choice. There are several advantages to EPL, such as a large depth of focus and a lower relative mask cost. Significant challenges also face this technology, including the limitation of the membrane format of the mask. One of the obstacles with the membrane format is image placement distortions, which can be very sensitive to the stress of the membrane as well as the pattern density. This paper studies how the stress of various types of films effects image placement distortions, as well as examines the effect of final mask cleans on image placement distortions.
The role of point-of-care β-hydroxybutyrate testing in the diagnosis of diabetic ketoacidosis: a review

The number of patients with diabetes and diabetes-related complications is increasing. Rapid and accurate diagnosis is key to efficiently providing the appropriate level of care for patients with diabetes. When faced with a hyperglycemic patient (ie, blood glucose level > 250 mg/dL), the prevailing attitude among health care providers is to "think worst first," and common clinical practice is to perform an evaluation for diabetic ketoacidosis (DKA). Traditionally, diagnosing DKA in accordance with the American Diabetes Association guidelines requires performing ≥ 2 (possibly 3) tests to obtain measurements for blood glucose, serum bicarbonate, serum pH, and serum anion gap levels, as well as measurements of either urine or serum ketone bodies. Recently, commercial point-of-care β-hydroxybutyrate measurement devices have become readily accessible and less expensive. These devices offer the potential to simplify clinicians' diagnostic approach to hyperglycemic patients. In this evidence-based literature review, we describe the use of point-of-care β-hydroxybutyrate testing for diagnosing DKA, and discuss its limitations in determining DKA severity.
Synthesis and radiobiological applications of [35S]L-homocysteine thiolactone.

Abstract [ 35 S]l-Homocysteine thiolactone ([ 35 S]l-HCTL) was synthesized and its biodistribution evaluated as a potential brain radioprotective agent and as a tissue hypoxia marker. Drug uptake in mouse brain exceeded that in s.c. tumor 3 h post injection only. Multiple indicator dilution experiments in the rabbit heart indicate that membrane permeability of [ 35 S]l-HCTL does not limit its usefulness as a hypoxia marker. In addition, a positive correlation was observed between regional coronary blood flow and myocardial content of [ 35 S]adenosylhomocysteine formed from [ 35 S]homocysteine and adenosine.
Evidence of avian metapneumovirus subtype C infection of wild birds in Georgia, South Carolina, Arkansas and Ohio, USA.

Metapneumoviruses (MPVs) were first reported in avian species (aMPVs) in the late 1970s and in humans in 2001. Although aMPVs have been reported in Europe and Asia for over 20 years, the virus first appeared in the United States in 1996, leaving many to question the origin of the virus and why it proved to be a different subtype from those found elsewhere. To examine the potential role of migratory waterfowl and other wild birds in aMPV spread, our study focused on determining whether populations of wild birds have evidence of aMPV infection. Serum samples from multiple species were initially screened using a blocking enzyme-linked immunosorbent assay. Antibodies to aMPVs were identified in five of the 15 species tested: American coots, American crows, Canada geese, cattle egrets, and rock pigeons. The presence of aMPV-specific antibodies was confirmed with virus neutralization and western blot assays. Oral swabs were collected from wild bird species with the highest percentage of aMPV-seropositive serum ...
A genetic-physical map of the Rhodobacter capsulatus carotenoid biosynthesis gene cluster

We used the interposon mutagenesis technique to map a cluster of Rhodobacter capsulatus genes that are responsible for the biosynthesis of carotenoids, membrane pigments that protect living organisms from photooxidations. Fifteen interposons define 7 genes (crtA, crtI, crtB, crtC, crtD, crtE and crtF) in an approximately 8 kb of the chromosome. This cluster is flanked by genes affecting bacteriochlorophyll biosynthesis. Based on the analysis of the phenotypes of the insertional mutants and the results of complementation analyses, we present a genetic and physical map of this region. Our data indicate that, with the possible exception of crtI and crtB, all genes analyzed are organized as single transcriptional units. We used nuclease S1 protection analysis to study the influence of oxygen on the regulation of expression of 4 genes (crtA, crtI, crtC and crtE). Under anaerobic conditions, mRNA levels for crtA, crtC and crtE are elevated and a new crtE transcript is detected.
Electrostatic dust transport on Eros: 3-D simulations of pond formation

Abstract NEAR–Shoemaker spacecraft images of the surface of the near-Earth Asteroid 433 Eros reveal that more than 200 craters on Eros are partially filled with smooth deposits, termed ponds [Veverka, J., and 32 colleagues, 2001a. Science 292, 484–488]. These ponds appear smooth even at a high resolution of 1.2 cm/pixel and spectral analysis suggests that they may be made up of particles ≪50 μm in size [Robinson, M.S., Thomas, P.C., Veverka, J., Murchie, S., Carcish, B., 2001. Nature 413, 396–400; Riner, M.A., Eckart, J.M., Gigilio, J.G., Robinson, M.S., 2006. Lunar Planet. Sci. XXXVII. Abstract 2291]. Coupled with the concentration of ponds at low latitudes, the possible small particle size suggests that these deposits might be related to electrostatic transport of dust near the local terminator [Robinson, M.S., Thomas, P.C., Veverka, J., Murchie, S., Carcish, B., 2001. Nature 413, 396–400]. The work presented here incorporates the precise lighting geometry within a crater at a specified latitude into two models for electrostatic transport of dust grains in order to explore dust deposition and pond formation via this mechanism, particularly as a function of latitude. We find that micrometer-sized dust particles are preferentially transported into craters at latitudes where solar illumination angles are often low. In addition we find that if particles are electrostatically lifted off the surface they are preferentially transported into topographic depressions independent of whether the particles undergo stable levitation. The primary limiting factor for our model is uncertainty concerning the dust launching mechanism. Despite that, and though it does not match the observed north–south asymmetry in pond distribution, our model demonstrates potential for good general agreement between future predictions of pond formation via electrostatic transport of dust and observations of pond locations on the surface of Eros.
Characterization of coronary vein motion in patients with low and moderate ejection fractions

Objective To quantify periods of low motion of the coronary veins in patients with low and moderate EF in order to optimize acquisition of whole-heart coronary magnetic resonance venograms (cMRV). Background Three-dimensional, whole-heart, navigator-gated, contrast-enhanced MRI techniques are used to acquire cMRVs which can be used for planning lead placement in cardiac resynchronization therapy (CRT). In order to reduce cardiac motion artifacts, it is desirable to set the trigger delay time to acquire image data only during periods of low vessel motion, typically assumed to be during diastole. By knowing the temporal length and location of the low motion period, the acquisition window can be optimized for coronary vein imaging. Previous studies have examined coronary artery motion, but an analysis of the coronary veins has not been performed. Methods 32 total patients were analyzed. These patients were considered in 3 groups: 13 patients scheduled for CRT (LVEF 120ms), 6 patients with low LVEF but normal ECG (LVEF 35%, QRS 35%) had a longer diastolic rest period, 3) 4 patients with a longer systolic rest period had no diastolic rest period.
A simple proof of the uniqueness theorem in impedance tomography

Abstract Let∇·(σ(x)∇u)= 0 in D ⋐ R3, where D is a bounded domain with a smooth boundary. Suppose that σ ≥ m > 0, σ ∈ H3(D), where Hl is the Sobolev space. Let the set {u, σuN} be given on Γ for all u ∈ H 3 2 (Γ) , where uN is the normal derivative of u on Γ.
Mid‐trimester fetal ultrasound: Diagnostic dilemmas

Two cases are reported in which an unusual ultrasound finding preceded diagnostic amniocentesis and led to further work-up. In both cases a decision was made to terminate the pregnancy. One fetus in which a neck mass was detected by ultrasound was shown to be normal on post-mortem examination. The second fetus was aborted because of Rh sensitization and had the abnormality seen by ultrasound. However, this lesion, calcified intrahepatic plaques, had no presumed pathological significance. These cases suggest caution in the interpretation of results obtained with the new technologies used for prenatal diagnosis.
The effect of oxygen-to-fuel stoichiometry on coal ash fine-fragmentation mode formation mechanisms

Abstract Ash particles smaller than 2.5 μm in diameter generated during pulverized coal combustion are difficult to capture and may pose greater harm to the environment and human health than the discharge of larger particles. Recent research efforts on coal ash formation have revealed a middle fine-fragment mode centered around 2 μm. Formation of this middle or fine-fragment mode (FFM) is less well understood compared to larger coarse and smaller ultrafine ash. This study is part of an overall effort aimed at determining the key factors that impact the formation of FFM. This work examined the effects of oxygen-to-fuel stoichiometry (OFS). Pulverized Illinois #6 bituminous coal was combusted and the ash generated was size segregated in a Dekati low pressure inertial impactor. The mass of each fraction was measured and the ash was analyzed using scanning electron microscopy (SEM) and X-ray microanalysis. The FFM ash types were classified based on the SEM images to evaluate the significant fine-fragment ash formation mechanisms and determine any possible link between stoichiometry and formation mechanism. From the particle size distributions (PSDs), the coarse mode appears unaffected by the change in OFS, however, the OFS 1.05 lowered the fraction of ultrafine ash in relation to the higher OFS settings, and appears to increase the portion of the FFM. An intermediate minimum was found in the FFM at 1.3 μm for the 1.20 and 1.35 OFS tests but was not observed in the 1.05 OFS. SEM analysis also suggests that OFS may contribute to changing formation mechanisms.
Kinetics of Silicon Monoxide Ammonolysis for Nanophase Silicon Nitride Synthesis

Silicon monoxide vapor generated from Si/SiO{sub 2} mixed-powder compacts was used with NH{sub 3} to synthesize silicon nitride in a tubular flow reactor operated at temperatures in the range of 1,300--1,400 C. The ammonolysis of SiO with excess NH{sub 3} was very rapid, yielding three different types of silicon nitride at different longitudinal locations in the reactor: amorphous nanophase powder of an average size of about 20 nm, amorphous whiskers of a few micrometers in diameter, and {alpha}-polycrystals. The amorphous products were heat-treated for crystallization at temperatures between 1,300 and 1,560 C in a stream of dissociated NH{sub 3}, N{sub 2}, or N{sub 2}/H{sub 2} mixture gas. When dissociated NH{sub 3} was used, nanophase powder was crystallized at 1,300 C. The yield of nanophase silicon nitride from SiO varied from 13% to 43%, depending on operating conditions.
Identifying techniques, topologies and features for maximizing the efficiency of a distribution grid with solid state power devices

The FREEDM grid utilizes solid state transformers (SST) and solid state fault interruption devices (FID) which may lead to unfavorable operating losses as compared to a conventional grid. Various SST topologies and switching techniques are identified for minimizing losses and a performance evaluation is made to determine the efficiency of the FREEDM distribution network to improve the overall efficiency. Losses include conductors, SSTs, FIDs, and conventional distribution transformers tested under various loading levels. Compared to a conventional distribution network, the FREEDM grid has a slight reduction in losses. By choosing the proper distribution line configuration, conductor type, switching devices and switching techniques, the power losses on the system may be minimized further.
Performance of Reverse Electrode HPGE Coaxial Detectors after Light Damage by Fast Neutrons

Several reverse electrode HPGe coaxial detectors fast neutron-damaged to various fluences were annealed at room temperature for varying periods of time. For comparison, in one case a dry ice temperature anneal was made. The result of these annealings on the energy resolution at 1.33 MeV was measured. The effect of source intensity and energy on the energy resolution and line shape are discussed.
Primary hyperparathyroidism: a prospective clinical study.

Abstract The results of the first thirty months of a long-term prospective study of primary hyperparathyroidism are presented. This study was designed to evaluate the course of asymptomatic patients without complications for whom surgical treatment is deferred as well as the effects of successful surgical treatment on the complications of the disease. Included in the last fifteen months of the study was the measurement of serum immunoreactive parathyroid hormone (IPTH). The majority of the patients without symptoms or complications did well without surgical treatment. Operation eventually was required in 13.8 per cent of these patients. There was no trend in serial serum IPTH values in the thirty patients for whom they were available. Removal of the parathyroid lesion does not ensure cure of primary hyperparathyroidism. Four patients had persistent hyperparathyroidism and three had recurrent hyperparathyroidism among the 171 patients with proved hyperparathyroidism. In patients with significant renal impairment prior to parathyroid surgery further renal deterioration may develop after the removal of an adenoma, but so far this has been reversible. The serum calcium was less than 11 mg/100 ml in fifty-one (31 per cent) of the patients with proved hyperparathyroidism. Serum IPTH values correlated positively with serum calcium values and tumor weights, differing from normal in which there is a negative correlation with serum calcium. Serum IPTH values have been most useful in the evaluation of hypercalcemia when the etiology is not clear. Renal lithiasis was present in 51 per cent of the patients with proved hyperparathyroidism but was thought to be metabolically active in only 10.5 per cent. Roentgenographic bone disease, occurring in 24 per cent of patients with proved hyperparathyroidism, appeared to represent a subpopulation with higher serum calcium, alkaline phosphatase and IPTH values as well as larger tumors. Primary hyperparathyroidism may be much more common than previously suspected, occurring frequently in an asymptomatic form without complications and detected by screening technics. As yet, it is not clear which of these patients should have surgical treatment.
Multimale mating and absence of canine tooth dimorphism in woolly spider monkeys (Brachyteles arachnoides)

The relatively low degree of canine tooth dimorphism in Australopithecus afarensis has been used as “primary evidence” to support the concept of a mating system of monogamous pair-bonding and male provisioning. A recent field study of woolly spider monkeys shows that these large primates, which lack canine tooth (and body size) dimorphism, are characterized by apolygynous mating system. Male parental care of infants is absent in this species. These data support the view that a lack of canine tooth dimorphism in an anthropoid species does not necessarily imply either a monogamous, pair-bonded mating system or male parental care.
An RF receiver with an integrated adaptive notch filter for multi-standard applications

This paper presents a 2.4GHz current-mode RF direct-conversion receiver implemented in a 90nm CMOS process with a novel adaptive notch filter. The notch filter uses the blocker frequency to up-convert a DC null to the pass-band, attenuating the blocker before entering the receiver. A synthesized inductor on the order of μH realizes the DC null. Blocker attenuation as large as 20dB is observed at a 40MHz offset frequency while the in-band attenuation increases by only 2dB. This proves that this technique is effective in attenuating blockers in broadband multi-standard radios without using any high-Q mechanical filters at their front-ends.