cssi/SciSciGPT-SciSciNet huggingface dataset:
The B-Nd (boron-neodymium) system

Given the scientific and commercial significance of the ternary Nd-Fe-B system, it is surprising that so little is known about the Nd-B binary phase diagram. Figure 1, the assessed Nd-B diagram, was constructed using contributions from a number of sources. The diagram is similar to that for the B-Sm system. Its phases include the liquid, L; the two stable neodymium allotropes, (txNd) and ([3Nd), each with negligible solid solubility ranges; four intermetallic phases assigned the stoichiometries Nd2B 5, NdB4, NdB6, and NdB66; and the terminal solid solution, (~B), with negligible solubility for Nd. The liquidus temperatures and invariant compositions are estimated, largely based on results f0r the B-Sm system [76Spe, 77Spe].
Separation of pressor and antidiuretic effects of intraventricular bradykinin

Abstract Intraventricular (i.v.t.) injections of bradykinin have been reported to produce centrally mediated pressor effects. Here it is reported that intraventricular bradykinin infusions produce antidiuretic effects in addition to pressor effects previously reported. Median eminence lesions block the antidiuretic but not the pressor effects of central bradykinin, suggesting that ADH release is the major component of antidiuresis but that other central mechanisms, probably sympathetic outflow, mediate the blood pressure increase. The similarity of central effects seen with bradykinin and angiotensin II suggests a common mechanism of action within the central nervous system.
Recursive approach to the moment-based phase unwrapping method

The moment-based phase unwrapping algorithm approximates the phase map as a product of Gegenbauer polynomials, but the weight function for the Gegenbauer polynomials generates artificial singularities along the edge of the phase map. A method is presented to remove the singularities inherent to the moment-based phase unwrapping algorithm by approximating the phase map as a product of two one-dimensional Legendre polynomials and applying a recursive property of derivatives of Legendre polynomials. The proposed phase unwrapping algorithm is tested on simulated and experimental data sets. The results are then compared to those of PRELUDE 2D, a widely used phase unwrapping algorithm, and a Chebyshev-polynomial-based phase unwrapping algorithm. It was found that the proposed phase unwrapping algorithm provides results that are comparable to those obtained by using PRELUDE 2D and the Chebyshev phase unwrapping algorithm.
The subcellular distribution and partial characterization of cholinesterase activities of canine platelets.

Abstract The multiple cholinesterase activities in canine platelets have been investigated. Platelets were homogenized by rapid decompression under nitrogen, glass tube/Teflon pestle, and glycerol lysis techniques. Rapid decompression under nitrogen technique was found to be the most efficient and gentle method for cell disruption. Homogenates were subfractionated using sodium diatrizoate density gradients. Marker enzyme assays and pulse labeling experiments with 5-hydroxy[ 14 C]tryptamine and [ 125 I]thrombin on prepared subcellular fractions confirmed that the soluble, plasma membrane and the granule-1 fractions were all in reasonably pure form. Furthermore, labeling of the plasma membrane with [ 125 I]thrombin is cited as the first successful attempt at attaining a significantly bound marker for this structure. Cholinesterase activity distributions measured in these fractions indicated that about 30% of the activity was present in the plasma membrane, 50% in granule-1 and 5% in soluble fractions. Kinetic data of cholinesterase activities obtained from intact platelets, plasma membrane preparations and platelet release supernatants indicated that they are strikingly similar.
Graphics processing unit-based ultrahigh speed real-time multidimensional Fourier domain optical coherence tomography

In this paper, we systematically presented a series of graphics processing unit (GPU) based data processing methods for ultrahigh speed, real-time Fourier Domain optical coherence tomography (FD-OCT): GPU based algorithms including high-speed linear/cubic interpolation, non-uniform fast Fourier transform (NUFFT), numerical dispersion compensation, and multi-GPU implementation were developed to improve the image quality and stability of the system. Full-range complex-conjugate-free FD-OCT was also implemented on the GPU architecture to double the imaging range and to improve SNR. The maximum processing speed of >3.0 Giga-Voxel/second (>6.0 Mega-A-scan/ second of 1024-pixel FD-OCT) was achieved using NVIDIA's latest GPU modules. The GPU-based volume rendering enabled real-time 4D (3D+time) FD-OCT imaging, and a 5 volume/second 4D FD-OCT system was demonstrated. These GPU technologies were highly effective in circumventing the imaging reconstruction and visualization bottlenecks exist among current ultra-high speed FD-OCT systems and could significantly facilitate the interventional OCT imaging.
The regulation of drugs and medicines in horse racing in the United States. The Association of Racing Commissioners International Uniform Classification of Foreign Substances Guidelines

The primary reason for developing the ARCI Uniform Classification of Foreign Substances was to give stewards and other racing regulators guidelines to assist them in understanding the relative performance effects and general offensiveness to the Rules of Racing of various drugs and medications. As such, these guidelines have been very useful in the world of racing regulation--officially or unofficially--because this classification system, for the first time, places a relative number on the inappropriateness of any one of more than 750 agents appearing in forensic samples taken from racing horses. The guidelines set up by this system established the first framework for dialogue among veterinary pharmacologists reviewing these drugs. Prior to development of the guidelines, pharmacologists had their own opinions about these agents and their effects on performance. The guidelines, however, established a framework for discussion, and there has been surprising unanimity about the classification of each of these agents. Not only does this classification system provide a useful basis for dialogue among experts, it is also useful for regulators, horsemen and other laymen, most of whom have little training or experience with drugs and their effects on horses. The system is easily understandable and communicates the relative possibility of any classified substance to affect the performance of a horse. Consequently, the system has made it possible for laymen to understand the degree of impropriety of all drugs and medicines with which they may have contact. Grouping a large number of drugs into specific classes has greatly facilitated discussion about regulations and penalties, and the classification system is related to proposed penalty guidelines which were developed in parallel. With regard to penalties for Class 1 agents, it is easy to assign and defend substantial penalties after examining the guideline statement describing the possible performance effects of this group of agents as well as the fact that they have no well recognized therapeutic role. Similarly, the relatively modest effects of class 4 and 5 agents, combined with the fact that these groups encompass a large number of well recognized therapeutic agents, helps in understanding the possible presence of trace levels of these agents in post-race samples. In summary, the ARCI Uniform Classification of Foreign Substances Guidelines condenses data on drugs and medications and places them into a simple five class system. This system has made it possible to confidently discuss the regulatory implications of the identification of any one of the approximately 750 classified substances potentially found in forensic samples from a performance horse. As such it facilitates both the development and implementation of more understandable and equitable regulatory processes.
Dentin apposition rates as markers of primate growth

The incremental lines of von Ebner frequently have been described as ultradian markers of dentin calcification. To determine the relationship between these lines and the quantity of dentin formed, reference was made to an in vivo marker of calcification, tetracycline. These markers were produced by injecting four juvenile monkeys periodically over a period of 175 days. These animals had been subjects in the heat stress study and were exposed to a series of heat stresses and cortisone injections. At the end of the study, undecalcified thin sections of premolars and second molars were prepared by standard histological techniques. We found that linear apposition rates increased in a gradient toward the pulp chamber. These rates varied within each tooth but not in corresponding parts of different teeth. Also, we determined that dentin apposition can be temporarily depressed by certain metabolic stresses. Heat load and cortisone significantly slowed dentin formation. Each depression, however, was followed by a "catch-up" period. Incremental line distances also increased as a function of the distance from the dentoenamel junction. There was, however, no systematic relationship between apposition rates and incremental line distance; these distances did not deviate from the observed trends during periods of slowed apposition. Incremental lines may by interpreted, not as natural growth markers, but as structural phenomena which are a function of dentin geometry and tubule bending.
Subjective Stress and Self-Esteem of Police Officers

Lester (1982) reported that the level of subjectively perceived stress in police officers was related to a belief in an internal locus of control. To explore additional correlates of subjeccively perceived stress in police officers, 78 police officers (M age = 35.0 yr., SD = 6.3) in advanced training courses were given anonymously an inventory to measure subjectively perceived stress levels (Wilcher, 1980), an inventory to measure low self-esteem (Girdano & Everely, 1977), and Rotter's (1966) measure of belief in an external locus of control." Officers reporting higher levels of subjectively perceived stress had significantly lower self-esteem scores (Pearson r = -0.28, one-tailed p = 0.006) but did not differ in their belief in an external locus of control (r = 0.11). Low self-esteem was significantly associated with a stronger belief in an external locus of control (r = -0.20, p = 0.04). Although this study did not yield an association between subjectively perceived levels of stress and belief in an external locus of control, police officers with lower self-esteem did report higher levels of subjectively perceived stress.
Ventral Tegmental Area Glutamate Neurons: Electrophysiological Properties and Projections

The ventral tegmental area (VTA) has a central role in the neural processes that underlie motivation and behavioral reinforcement. Although thought to contain only dopamine and GABA neurons, the VTA also includes a recently discovered population of glutamate neurons identified through the expression of the vesicular glutamate transporter VGLUT2. A subset of VGLUT2+ VTA neurons corelease dopamine with glutamate at terminals in the NAc, but others do not express dopaminergic markers and remain poorly characterized. Using transgenic mice that express fluorescent proteins in distinct cell populations, we now find that both dopamine and glutamate neurons in the medial VTA exhibit a smaller hyperpolarization-activated current (Ih) than more lateral dopamine neurons and less consistent inhibition by dopamine D2 receptor agonists. In addition, VGLUT2+ VTA neurons project to the nucleus accumbens (NAc), lateral habenula, ventral pallidum (VP), and amygdala. Optical stimulation of VGLUT2+ projections expressing channelrhodopsin-2 further reveals functional excitatory synapses in the VP as well as the NAc. Thus, glutamate neurons form a physiologically and anatomically distinct subpopulation of VTA projection neurons.
Relation between the sixth-order vacuum polarization coefficientb6 and the sixth-order Gell-Mann-Low functionψ6

A relationship between the sixth-order vacuum polarization coefficientb6 and the sixth-order Gell-Mann-Low functionψ6 is derived using the Gell-Mann-Low equation and the Callan-Symanzik equation.
Coloring number and on-line Ramsey theory for graphs and hypergraphs

Let c,s,t be positive integers. The (c,s,t)-Ramsey game is played by Builder and Painter. Play begins with an s-uniform hypergraph G 0=(V,E 0), where E 0=O and V is determined by Builder. On the ith round Builder constructs a new edge e i (distinct from previous edges) and sets G i =(V,E i ), where E i =E i−1∪{e i }. Painter responds by coloring e i with one of c colors. Builder wins if Painter eventually creates a monochromatic copy of K s t , the complete s-uniform hypergraph on t vertices; otherwise Painter wins when she has colored all possible edges. We extend the definition of coloring number to hypergraphs so that χ(G)≤col(G) for any hypergraph G and then show that Builder can win (c,s,t)-Ramsey game while building a hypergraph with coloring number at most col(K s t ). An important step in the proof is the analysis of an auxiliary survival game played by Presenter and Chooser. The (p,s,t)-survival game begins with an s-uniform hypergraph H 0 = (V,O) with an arbitrary finite number of vertices and no edges. Let H i−1=(V i−1,E i−1) be the hypergraph constructed in the first i − 1 rounds. On the i-th round Presenter plays by presenting a p-subset P i ⊆V i−1 and Chooser responds by choosing an s-subset X i ⊆P i . The vertices in P i − X i are discarded and the edge X i added to E i−1 to form E i . Presenter wins the survival game if H i contains a copy of K s t for some i. We show that for positive integers p,s,t with s≤p, Presenter has a winning strategy.
Alpha-Hematite: Stable Remanence and Memory

Experimental evidence suggests that the magnetization of α-Fe2O3 consists of a soft spin-canted moment and a hard defect moment. The former is observed in the range -20° to 675°C; the latter is mai...
A film-rupture model of hydrogen-induced, slow crack growth in acicular alpha-beta titanium

A study has been conducted of the terrace-like fracture morphology of gaseous hydrogen-induced crack growth in acicular alpha-beta titanium alloys in terms of specimen configuration, magnitude of applied stress intensity, test temperature, and hydrogen pressure. Although the overall appearance of the terrace structure remained essentially unchanged, a distinguishable variation is found in the size of the individual terrace steps, and step size is found to be inversely dependent upon the rate of hydrogen-induced slow crack growth. Additionally, this inverse relationship is independent of all the variables investigated. These observations are quantitatively discussed in terms of the formation and growth of a thin hydride film along the alpha-beta boundaries and a qualitative model for hydrogen-induced slow crack growth is presented, based on the film-rupture model of stress corrosion cracking.
Parameterization of Ice Growth for Numerical Calculations of Cloud Dynamics

Abstract Parametric equations describing the growth of ice particles in the range 10−11–1 g are presented. Three subranges (10−11–5 × 10−8, 5 × 10−8–10−4, and 10−4–1 g) are used. The parametric equations were developed with the aid of a complex method of calculating ice-particle growth. Two approaches to using the parametric equations in a simulation resembling a natural cloud situation are described. One method breaks the ice-particle spectrum into three components, the sizes of each being monitored. The other assumes a size distribution that can be characterized by a “growth-median” size, so that only one size need be monitored to describe the rate of growth. The parametric method is compared with more complicated methods in a simulated cloud environment, and the results are regarded as satisfactory.
Compositional and Electrochemical Characterization of Noble Metal−Diamondlike Carbon Nanocomposite Thin Films

A detailed characterization of platinum- and gold-diamondlike carbon (DLC) nanocomposite films deposited onto silicon substrates is presented. A modified pulsed laser deposition (PLD) technique was used to incorporate noble metal nanoclusters into hydrogen-free DLC films. Several analytical techniques, including transmission electron microscopy, atomic force microscopy, Rutherford backscattering spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and nanoindentation testing, were used to investigate these thin films in an effort to determine their physical and electrochemical properties. Rutherford backscattering spectroscopy indicated that the gold- and platinum-DLC films contain metal concentrations between three and 36 atomic percent. Cross-sectional transmission electron microscopy revealed that metal is present as arrays of noble metal islands embedded within the DLC matrix, while atomic force microscopy provided evidence of target splashing. In addition, due to the inclusion of metal, metal-DLC thin films exhibited greater conductivity than their metal-free counterparts. The electrochemical properties were studied using quasi-reversible redox couples and correlated to the metal concentration. Finally, the influence of the layer's composition on the electron-transfer kinetics and the achievable working potential window is discussed. The results discussed herein suggest that metal-DLC thin films grown by pulsed laser deposition present a promising alternative electrode material for electrochemistry.
Effects of low-voltage electron beam lithography

To examine the practical limits and effects of low voltage operation, studies of electron beam lithography (EBL) in the low (few keV) to ultra-low (E < 500eV) energy range, employing commonly used resists such as PMMA was done, and the results were compared to those from conventional high voltage processing. The direct writing was performed at low energies by our homemade scan generator and a Schottky field emission gun scanning electron microscope (SEM), used in cathode-lens mode for ultra-low voltage operation. The exposure characteristics and sensitivity of the system at these energies have been investigated using an advanced Monte Carlo simulation method. Our modeling of the lithographic process showed a significant increase in resolution and process latitude for thinner resists.
Rhetoritherapy Versus The Medical Model: Dealing With Reticence

Anxiety no longer appears to be a major factor in determining treatment for problem communicators. The medical model has been rejected for a rhetorical model which permits a rhetoritherapist to retrain the client in the rhetorical sub‐processes in order to improve his or her communication capability.
Notes on the genus Chionolaena in Colombia with a new species Chionolaena barclayae (Asteraceae, Gnaphalieae)

A new species and a new record for Chionolaena are recorded from Sierra Nevada de Santa Marta, Colombia adding to the two species of the genus already known from that mountain complex.
Tangential loading of elastic bodies in contact

Abstract This paper concerns the elastic contact between two bodies which are pressed together by normal loads and are given a tangential relative displacement. The tangential load is not sufficient to cause sliding over the entire contact region so that a portion of the contact sticks while the remainder slips. The two bodies can have different geometrical and elastic properties. Using rectangular subdivisions for the normal and tangential stresses, a numerical scheme for the complete sliding and stick-slip cases is developed. The contact region for complete sliding is first found and assumed to be approximately correct for the stick-slip case. The method is iterative and convergence to the unknown shape of the contact region (complete slip) and the shape of the stick region (stick-slip) is rapid.
Assessing the Simultaneous Effects of Modeled Interventions: Value-Added and ANOVA Approaches

We urge the use of modeling before experimentation to judge the effects of possible interventions for dealing with social problems. This article provides two approaches for assessing the separate and joint effects of such intervention models. The value-added approach decomposes effects in a manner analogous to stepwise regression whereas the ANOVA approach decomposes the effects according to the analysis-of-variance model. The two approaches are applied to a model for the achievement of racial equality in an occupational group at a local level. The treatment effects of an affirmative action program and growth in the number of jobs are analyzed with the two approaches
Phospho-flow cytometry based analysis of differences in T cell receptor signaling between regulatory T cells and CD4+ T cells.

CD4+ T regulatory cells (Tregs) are activated during auto-immune, injury, and inflammatory responses, however, the molecular events that trigger Treg activation are poorly understood. The purpose of this study was to investigate whether Tregs (FoxP3+ CD4+ T cells) and non-Treg CD4+ T cells might display differences in T cell receptor (TCR) dependent signaling responses following in vitro or in vivo stimulation. This study used phospho-flow cytometry as a tool to profile the kinetics and extent of TCR signaling (ZAP-70 and PKC-θ phosphorylation and expression) in Tregs and non-Tregs. We found that in vitro stimulation with anti-CD3e induces early and transient activation of ZAP-70 and PKC-θ in both Tregs and non-Tregs. However, the response in Tregs was more rapid and higher in magnitude than responses seen in non-Tregs. In contrast, bacterial superantigen or antigen-specific TCR stimulation did not significantly activate these signaling pathways in Tregs or non-Tregs. Additional experiments tested the kinetics of in vivo TCR signaling in Tregs and non-Tregs in mice challenged with bacterial superantigen. The results of these experiments showed that superantigen rapidly activated ZAP-70 and PKC-θ in lymph node Tregs, but not in non-Tregs. In summary, we demonstrate the versatility of using phospho-flow cytometry to measure cell signaling in CD4+ T cells. The results of these in vitro and in vivo studies demonstrate that Tregs and non-Treg CD4+ T cells show marked differences in their reactivity to TCR-dependent stimulation and contribute new insights into basic mechanisms that lead to Treg activation.
Geometric Phase Effects in the Vibrational Spectrum of Na 3 ( X )

The lowest 89 vibrational energy levels for Na{sub 3}( X) for zero total angular momentum (J=0) are computed both with and without the geometric phase. The calculations are full dimensional (3D) and utilize the vector potential (gauge theory) approach for including geometric phase effects. It is shown that the geometric phase leads to large shifts in the vibrational energy levels which result in a different ordering of states. These results can be verified experimentally and represent the first {open_quotes}clean{close_quotes} example of a geometric phase effect in molecular spectra. {copyright} {ital 1997} {ital The American Physical Society}
Zooming in on the Redshift Problem

Scientific inference offers a way to help organize and clarify our thinking about controversial areas of science such as the redshift problem. Scientists typically devote considerable effort to evaluating the probability that data relevant to a controversial area may be due to the ”null hypothesis” (i.e. that there is no new phenomenon). However, it is usually not clear whether a small probability for the null hypothesis can be interpreted as a high probability for some other hypothesis, if only for the reason that the alternative hypothesis may not be specified, and it is not clear how strong a case is required to establish the new hypothesis. Thinking about such topics can be clarified by a simple procedure based on the methods of scientific inference. This procedure is referred to as “ZOOM” for “Zero-Order Organizing Model.” This article proposes a ZOOM for the redshift problem, and presents the results of a preliminary trial.
Cognitive coping, history of depression, and cigarette smoking.

Abstract People with a history of depression are less likely to succeed in quitting smoking than are those with no depression history. Efforts to help formerly depressed smokers by incorporating the principles and techniques of cognitive behavior therapy (CBT) of depression have yielded mixed results. This study tested a major premise of such treatment programs, that formerly depressed smokers are indeed lacking in cognitive coping skills taught in CBT. Four groups (Positive vs. Negative Depression History × Current Smoker vs. Never Smoker) completed the Ways of Responding (WOR) as a test of cognitive coping. History of depression was associated with use of significantly more “negative” (considered maladaptive by expert cognitive therapists) responses on the WOR. Smokers gave WOR responses lower in quality, as rated by independent coders, than those of nonsmokers. Results are discussed in relation to implications for treatment and for future research.
The Solar Wind and Its Magnetic Sources at Sunspot Maximum

We use in situ measurements from the Advanced Composition Explorer and magnetograph data from the National Solar Observatory to relate the properties of the solar wind during 1998-2002 to its source region magnetic fields. The great bulk of the solar maximum wind is characterized by low proton speeds (vp ~ 420 km s-1) and high oxygen charge state ratios (nO7+/nO6+ ~ 0.3). This slow wind originates from small, sheared open-field regions located near active regions and characterized by very large flux tube expansion factors (fexp 10) and high footpoint field strengths (B0 ~ 30 G). In contrast, the occasional high-speed streams emanate from weak-field regions (B0 ~ 5 G) with small expansion factors (fexp ~ 4) and show relatively low charge state ratios (nO7+/nO6+ ~ 0.1); their proton velocities (vp ~ 550 km s-1) are substantially reduced by interactions with the surrounding sea of low-speed wind. We attribute the high freeze-in temperatures of the slow wind to enhanced heating taking place in the low corona in the presence of the very strong, rapidly diverging source fields, which are found to be correlated with high mass and energy flux densities at the coronal base.
Ground state energies of bound exciton for all mass ratios

Abstract We report on a calculation of the ground state energy of bound excitons using states from a model Hamiltonian and correcting the variational results by treating the difference between the model and actual Hamiltonian in second order perturbation theory. The resulting procedure is valid for all mass ratios.
Discriminating the effects of agricultural land management practices on soil fungal communities

The structure of fungal communities was examined in soil subjected to 5 years of different agricultural land management and tomato production practices. Length heterogeneity polymerase chain reaction (LH-PCR) of fungal rDNA internal transcribed spacer-1 (ITS-1) regions was used to create genomic fingerprints of the soil fungal communities. Three years after initiation of land management practices, univariate analysis of genetic diversity failed to detect differences among soil fungal communities in plots managed organically, conventionally or maintained free of vegetation by continuous tillage (disk fallow). Genetic diversity was significantly higher in plots maintained as a perennial pasture grass (Paspalum notatum var Argentine bahiagrass) or as an undisturbed weed fallow. The composition of soil fungal communities within organic, pasture grass or disk fallow plots were separated into unique clusters by non-parametric multivariate analysis of their Bray-Curtis similarity matrices, computed from the relative abundance of ITS-1 amplicons, while the composition of communities within disk fallow and conventional plots could not be distinguished from each other. Diversity of soil fungal communities was significantly reduced following the cultivation of tomato in year four when compared to the diversity in plots where tomato was not cultivated. Divergence in the composition of soil fungal communities was observed following the cultivation of tomato under all land management regimes except organic, where communities continued to remained clustered based upon similarities among their ITS-1 amplicons. Divergence in the composition of fungal communities became more pronounced following two major hurricanes (Francis and Jeanne, September 2004) except for communities in the organic and pasture grass plots. Following the completion of a second tomato crop in year 5, genetic diversity and richness was similar under all land management regimes except the pasture grass, where it remained significantly higher. By contrast, following two consecutive years of tomato production, unique but mutually similar compositions of fungal communities were detected only in plots subjected to the organic land management regime. This was supported by observations that fungal communities were dominated by a 341 bp rDNA amplicon fragment in all land management regimes except the organic. Cloning and sequencing indicated that the 341 bp fragment generated by LH-PCR had a sequencing size of 343 bp, which was most closely related to Fusarium oxysporum. Thus, land management practices that disturb or disrupt soil fungal communities will significantly reduce their diversity. However, the composition of soil fungal communities is more strongly influenced by land management practices and communities within an organically management system were more resistant to anthropogenic and meteorological disturbances.
Pigmented Paravenous Chorioretinal Atrophy

Six patients (three men and three women, ranging in age from 19 to 65 years) with pigmented paravenous chorioretinal atrophy, a rare disorder of unknown origin, were studied for three- to 21-year periods. The diagnosis was made on the basis of the distinctive fundus appearance of bilateral, symmetrical bone corpuscular pigment accumulation exclusively along the distribution of the retinal veins. Although the fundus abnormalities can be mild or severe, retinal function tests indicated that this is a geographic and not a generalized disorder. Central visual acuities were normal. Follow-up studies showed no evidence of ophthalmoscopic or functional deterioration in five of the patients. In the sixth (Patient 6, the most severely affected), there was a mild progression of the fundus abnormality during the 21-year follow-up period.
The Prognostic Value of Pulmonary Vascular Capacitance Determined by Doppler Echocardiography in Patients with Pulmonary Arterial Hypertension

Objectives We sought to determine if a novel measurement of pulmonary vascular (PV) capacitance (PVCAP) by Doppler echocardiography predicts all-cause mortality in patients with primary pulmonary arterial (PA) hypertension (PPAH). Background The prognosis of patients with PPAH is variable and has been difficult to predict using clinical or hemodynamic parameters. PVCAP is a measure of the workload on the right ventricle (RV) and we recently have shown that PVCAP determined by cardiac catheterization is a strong predictor of survival. This same hemodynamic information to calculate PVCAP can be derived from Doppler echocardiography. Therefore, the purpose of this study was to determine if PVCAP from noninvasive Doppler echocardiography would be a useful measure of survival in patients with PPAH. Methods We analyzed clinical and hemodynamic variables on all patients with PPAH who had a right heart catheterization and echocardiogram from January to December 1999. Because capacitance is directly proportional to stroke volume and inversely proportional to PA pulse pressure, PVCAP was defined as stroke volume/pulse pressure. PVCAP was derived noninvasively from a comprehensive 2-dimensional and Doppler echocardiogram. Using the peak systolic tricuspid regurgitation velocity and the end-diastolic pulmonary regurgitation velocity, the modified Bernoulli equation was used to calculate the PA systolic and diastolic pressures, respectively. Stroke volume was obtained using the volumetric flow through the left ventricular outflow tract. PVCAP was then analyzed as a predictor of mortality, adjusting for other known modifiers of risk. Results In all, 54 patients (13 men) were studied with a mean age of 44 ± 11 years, ejection fraction of 62 ± 11%, and RV systolic pressure of 90 ± 21 mm Hg. In all, 24% were in World Health Organization (WHO) class II, 52% in class III, and 24% in class IV. During follow-up of 1498 ± 108 days, 12 patients died. The strongest noninvasive predictor of mortality was PVCAP (risk ratio 3.0/mL/mm Hg decrease in PVCAP, 95% confidence interval 1.2-8.0, P = .0212). WHO class, RV index of myocardial performance, RV systolic pressure, and RV ejection time were weaker predictors. PVCAP was also a stronger predictor of mortality than invasively determined PV resistance, right atrial pressure, and mean PA pressure. In multivariate analysis, PVCAP was the only noninvasive predictor of mortality. In quartile analysis the lowest PVCAP quartile had a 4-year mortality of 39% whereas the highest PVCAP had a mortality of 7%. Conclusion The novel measure of PVCAP, as determined by Doppler echocardiography, is a strong noninvasive predictor of mortality in patients with PPAH and adds prognostic value to conventional risk markers.
Why does DDT toxicity change after a blood meal in adult female Culex pipiens

Abstract The toxicity of topically applied DDT to adult female anautogenous mosquitoes ( Culex pipiens L.) showed dramatic variations in blood-fed insects. It decreased very rapidly about twofold to a minimum at 24 hr after a blood meal, then increased within 72 hr back to values typical of non-blood fed insects. A comparison of the metabolism of [ 14 C]DDT in vivo revealed an increase in DDT dehydrochlorination to DDE at 72 hr after a blood meal, but this increase was not responsible for the variations in DDT toxicity at 24 hr. Changes in penetration rates were not observed and changes in the distribution of DDT could likewise not be related to the short period of decreased toxicity of DDT. Fenvalerate and trans -permethrin, two pyrethroid insecticides which are believed to have a mode of action similar to that of DDT, were also significantly less toxic 24 hr after a blood meal. By contrast, the cyclodiene insecticide aldrin and the carbamate insecticide propoxur were not less toxic 24 hr after a blood meal. The results suggest that after a blood meal an unidentified and transient change in C. pipiens specifically decreases DDT/pyrethroid toxicity. A hypothesis concerning this transient change is advanced. The results illustrate the difficulties in explaining physiological changes in insecticide toxicity.
In situ infrared study of the catalytic ignition of methane on Pt/Al2O3

Abstract The ignition process of the partial oxidation of methane over Pt/Al2O3 catalysts has been investigated at atmospheric pressure using in situ DRIFT spectroscopy. Contacting methane with the catalyst shows that the dissociative adsorption of methane, evidenced by the appearance of the linearly adsorbed CO species, is delayed to higher temperatures for an oxygen-covered surface compared to an oxygen-free surface. Carbonate species were progressively obtained on the surface before the ignition temperature when interacting CH4/O2/He mixtures with the catalyst. They result from the interaction of produced carbon dioxide with the support. The temperature at which the carbonate species appears is lower for lower concentration of oxygen in the mixture. It has been shown that oxygen is mainly covering the surface until the ignition temperature. Competition between the two reactants is therefore assumed. It has been found that the state of platinum has a large effect on the ignition temperature, with the highest ignition temperature found for oxidized sample (platinum particle diameter, DPt = 1.9–2.2 nm), the next highest for freshly reduced sample (DPt = 1.7–1.9 nm), and the lowest on aged sample (DPt = 4–5 nm). All of these results linked to microcalorimetry measurements and literature data suggest that the heat of adsorption of oxygen is a key factor for ignition of the surface reaction.
Environmental equity: the demographics of dumping.

Research addressing “environmental equity” and “environmental racism” claims that facilities for treatment, storage, and disposal of hazardous wastes (TSDFs) are located disproportionately in minority areas. In the first comprehensive study of TSDFs to use census tract-level data, we find no nationally consistent and statistically significant differences between the racial or ethnic composition of tracts which contain commercial TSDFs and those which do not. TSDFs are more likely to be found in tracts with Hispanic groups, primarily in regions with the greatest percentage of Hispanics. Different geographic units of analysis elaborate on, but are consistent with, these results.
Did Jews Reshape the tale of the exodus

Erich Gruen's essay, "The Use and Abuse of the Exodus Story," is truly a fresh and challenging approach. The most controversial aspect of Gruen's thesis is his suggestion that the Diaspora Jews might have had a hand in molding the non-traditional parts of the story of Exodus. But, to judge from the inscriptions and papyri, they knew the Bible only in the Greek translation. According to the Letter of Aristeas, when the translation was completed, the leaders of the community declared that since it was "in every respect accurate, it is right that it should remain in its present form and that no revision of any sort take place". A curse was pronounced upon anyone who should add to or subtract from the translation. If the Jews in the Diaspora held the LXX in such high regard, they would hardly have invented stories about the desecration of other peoples' religion.Keywords: Bible; Diaspora; Erich Gruen; Exodus; Greek translation; Jews; LXX; reshape; The Use and Abuse of the Exodus Story
The effect of different surface barrier models on the Nottingham energy exchange process

Abstract TF emission current densities, total energy distributions and Nottingham inversion temperatures are calculated for three different models of the surface potential barrier. The models studied were: (i) Classical image potential, (ii) Quantum-modified image potential, (iii) Seitz-Van Oostrom modification of the image potential. The modified potential produced the expected lowering of the electron energy distribution and correspondingly reduced emission current densities. The third model potential also produced measurable changes for all quantities calculated. However, neither of the modified potentials yielded agreement with recent experimental values of inversion temperatures. Current work examining sources of this discrepancy are discussed.
Quantification of furosemide from serum and tissues using high-performance liquid chromatography.

Abstract Since pharmacokinetics may play a significant role in furosemide (FSM) developmental ototoxicity, we developed an assay for the extraction and quantification of FSM in tissue and fluid from neonatal and adult rats. Rats from post-natal day (PND) 10, 30 and 50, were given an intravenous dose of FSM (35 mg/kg). Blood and tissues were analyzed by HPLC. FSM in serum, perilymph and liver was elevated in PND ten rats as was the body burden of FSM. Renal concentrations were higher in older rats. Altered clearance of FSM in developing rats may result in higer concentrations in the cochlea and ototoxicity.
Proteases and lymphocyte cytotoxic killing mechanisms

Abstract A subfamily of serine proteases is uniquely expressed by cytotoxic natural killer lymphocytes and T cells. Protease cleavage of different natural substrates is now implicated in the cytotoxic: mechanisms of target cell membrane pore formation, DNA fragmentation and cytostasis.
NMDA receptor antagonists inhibit opiate antinociceptive tolerance and locomotor sensitization in rats

N-Methyl-d-aspartate (NMDA) receptors have an important role in different forms of behavioral and neural plasticity. Evidence suggests that these receptors may also be involved in plasticity arising from long-term treatment with different drugs of abuse, including tolerance, sensitization, and physical dependence. There is abundant evidence demonstrating that NMDA receptors are involved in tolerance to opiate-induced antinociception; however, the role of these receptors in sensitization to the locomotor effects of opiates is more controversial. The ability of NMDA receptor antagonists to modify the development of sensitization to the locomotor stimulant effect of three different opiates was examined. In selected studies, the ability of the antagonists to modify tolerance to the antinociceptive effects of the opiates was also examined. Adult male Sprague–Dawley rats were used to assess the effects of NMDA receptor antagonists (MK-801, memantine or LY235959) on tolerance and sensitization to three opiates: morphine, methadone, or buprenorphine. It was predicted that low, selective doses of the antagonists would inhibit the development of opiate tolerance and sensitization. Consistent with our predictions, the noncompetitive NMDA receptor antagonists MK-801 and memantine and the competitive NMDA receptor antagonist LY235959 inhibited the development of sensitization to the locomotor stimulant effect of morphine. Additionally, MK-801 inhibited the development of tolerance and sensitization to methadone and buprenorphine in a similar manner. The results, together with previous research, suggest that NMDA receptors are broadly involved in opiate-induced plasticity, including the development of opiate tolerance and sensitization.
The combination of interaural information across frequencies: lateralization on the basis of interaural delay.

Three experiments were carried out that employed low‐frequency tone complexes with interaural delays that varied across the frequency domain. In the first experiment, threshold interaural delays were measured for three‐tone complexes for which one, two, or all three components were delayed. The center frequency was 750 Hz and the frequency spacing (Δf ) between components was 20, 50, 100, 250, or 450 Hz. For all Δf’s, the presence of two diotic components elevated the threshold interaural delays obtained for the third component relative to that obtained for a pure tone of the same frequency. In the second experiment, observers made left–right judgments regarding the direction of movement of signals for which two components were delayed by 25 μs to the left ear during one interval and to the right ear during the other interval, while a third component of a variable time difference was delayed to the opposite side as the tone pair. Subjects reported single intracranial images during each interval, and the data showed that interaural delays of one component to one ear could be offset by interaural delays of the other two components to the other ear. In the final experiment, threshold interaural delays were measured for five‐tone complexes in which one, two, three, four, or five components were delayed. The center frequency was 750 Hz and Δf was fixed at 100 Hz. Thresholds decreased in a linear fashion as the number of delayed components increased, falling by about a factor of 5 as the number of delayed components went from one to five. These results are consistent with spectrally synthetic binaural processing, with the lateral position of intracranial images determined by a combination of interaural information across the spectrum. These effects could be brought about by a linear combination of the outputs of frequency‐specific cross‐correlation networks or by a wideband cross correlation of the signals at the two ears.
Entropic confinement of colloidal spheres in corners on silicon substrates

We have investigated depletion effects among dispersed, submicron, polystyrene spheres of two different sizes near a faceted silicon substrate. The larger spheres were confined to the corners where two silicon facets intersected (as where a wall meets a floor). The entropic confinement potential increased by 1.2kBT when the small-sphere volume fraction was increased by 14% to 0.37. Large-sphere crystallites nucleated along the corner and grew out along the flat surfaces before crystals nucleated on the flat surface or in the bulk. The results demonstrate a novel way to sort particles or to organize them along geometric features in a substrate for microfabrication.
Jensen's use of the Hick paradigm: Visual attention and order effects☆

Abstract Longstreth (1984, 1986) and Carroll (1987) have recently raised questions concerning the effects of practice and order and retinal displacement in Jensen's use of the Hick paradigm. The results of this study indicate that the effect of practice and order is nonsignificant. The effect of retinal displacement, although significant, accounts for such a small amount of the variance as to be of little practical or theoretical importance in Jensen's investigations with the Hick paradigm.
Wavelets and warping PS seismic images

The process of warping a PS seismic image to align reflectors with those in a PP seismic image can cause wavelet distortion. This distortion can be reduced by deconvolving the PS wavelet from the PS image, warping to PP time, and then convolving with the PP wavelet. Moreover, this warping-withwavelets algorithm can be used to estimate the required PS and PP wavelets. The primary difference between this new algorithm and previous methods is deconvolution of the PS wavelet before warping the PS image to PP time.
Tilt stripe textures in Langmuir monolayers of fatty acids

Abstract Quantitative studies are described of striped textures in Langmuir monolayers of tetradecanoic and pentadecanoic acids. The textures, which are the result of modulations of the tilt azimuths of the molecules, have been visualized with polarized fluorescence microscopy. The stripe widths change with pressure and temperature. When the monolayer is compressed beyond a threshold pressure, the stripes become unstable and form a zig-zag pattern, which is likely the result of a crossover between the bend and splay elastic constants in the monolayer.
The President’s New Freedom Commission: Capitalizing on Opportunities to Advance School-Based Mental Health Services

The report from President George W. Bush's New Freedom Commission on Mental Health (NFC), Achieving the Promise: Transforming Mental Health Care in America(2003), proposes goals and recommendations for improving mental health services. This report has significant implications for the delivery of mental health services through the schools. A focused discussion of the potential opportunities and challenges of implementing NFC recommendations related to school-based mental health is presented. Strategies for addressing five key areas at the intersection of school mental health and the Commission's recommendations include: stigma reduction, suicide prevention, expansion and improvement of school mental health, and screening and treatment of co-occurring mental health and substance abuse disorders.
Jones precoder for polarization mode dispersion compensation

A new electrical-domain precoder is proposed to mitigate polarization mode dispersion (PMD) in optical communications by modeling a PMD-dominant fiber optical channel using a single input multiple output (SIMO) channel. Employing a bank of finite impulse response filters and a polarization modulator, and using parameters derived from the Jones matrix representation of PMD, the proposed precoder efficiently adapts to the time-varying nature of PMD and simultaneously pre-equalizes both polarization modes at the transmitter. The transmitter-only structure avoids losing phase and polarization information due to the nonlinearity of the commonly used square law direct-detection receiver. Analysis is performed to evaluate the impact of channel mismatch due to feedback delay, channel estimation errors, and the impact of the finite length of the precoder filters. The analytical results are used to guide selection of the appropriate feedback rate for the adaptive system. Extensive simulation results confirm the efficiency of the proposed Jones precoder, and present it as an effective, low-cost replacement to the complicated, expensive optical-domain counter-parts.