cssi/SciSciGPT-SciSciNet huggingface dataset:
Characterization of hydrodynamic regimes in a bubble column

Abstract An experimental technique is developed to characterize the hydrodynamic regimes of a bubble column. This involves measurement and statistical analysis of temperature-history records of an element of the heat transfer surface immersed in the bubble column as a function of gas velocity. The data are taken in a 0.108m diameter bubble column for the nitrogen-water and nitrogen-Therminol systems at ambient conditions. The statistical functions computed at each gas velocity are the variance, autocorrelation function (acf), and the power spectral density function (psdf). The variations of variance and a mean frequency defined for the power spectral density data with gas velocity are found to characteristically represent the discrete bubbling, transitional and churn-turbulent regimes. It is shown that the experimentally observed characteristic variation of the overall heat transfer coefficient of an immersed surface in bubble column with gas velocity are in qualitative accord with the inferred hydrodynamic regime delineation information.
Sexual identity and self-concept

This study investigated the relationship among gender, social sex roles, and sexual orientation as components of sexual identity, and the relationship of these components to the overall self-concept. It was found that each component was individually important in the relationship of sexual identity to self-concept. The interaction between sex and sexual orientation suggested that different combinations of the female, male, heterosexual, and homosexual components had different relationships to self-concept. Women had higher scores than men on moral-ethical and family self-concepts. Homosexual persons as a group had self-concepts in the normal range, though they showed a greater number of minor deviations across several areas of self-concept than did their heterosexual counterparts. The homosexual sample endorsed more sex roles typical of the opposite sex than did the heterosexual sample, but the two groups did not differ in frequency of same-sex roles. Sex roles were related to self-concept in men but not in women. Among men, masculine and androgynous sex roles were associated with positive self-concept while feminine and undifferentiated sex roles were associated with less positive self-concepts. This supports the model of sex roles in which femininity and masculinity are conceived of and measured as separate dimensions.
Application of a full potential method for computation of three-dimensional supersonic flows

A nonlinear aerodynamic analysis technique based on the full potential equation in conservative form has been modified to permit treatment of supersonic flows with embedded subsonic regions (typically near the fuselage-canopy juncture and the wing leading edge). Solution procedures for the equations do not require any specific form of geometry or physical grid system. This results in the capability to analyze easily very complex geometries provided the posed problem lies within the isentropic restrictions of the full potential theory. Characteristic signal propagation theory is used to monitor the type dependent flow and a conservative switching scheme is employed to transition from the supersonic marching algorithm to a subsonic relaxation procedure and vice versa. An implicit approximate factorization scheme is used to solve the finite-difference equations. These modifications now permit analysis of fully three-dimensional flowfields including the interference effects due to lifting surface wakes. Improved grid generation capability allows analysis of complete complex aircraft geometries (fuselage, wing, tail, wing wake, and tail wake). Results are presented showing very good correlations with experimental surface pressure data and aerodynamic force data at both design and off-design operating points. Configurations examined include several waverider concepts, an arrow wing-body with wake, an advanced tactical fighter concept, and a fighter forebody-canard configuration.
Nuclear triiodothyronine binding in mononuclear leukocytes in normal subjects and obese patients before and after fasting.

We evaluated the maximum binding capacity (MBC) and dissociation constant (Kd) of nuclear T3 receptors (NT3R) in mononuclear cells in normal and obese subjects before and after fasting. Mononuclear cells were isolated by isopycnic centrifugation of 50 ml heparinized blood underlayered with Ficoll-Paque. From 1–5 X 106 cells (12–60 µg DNA) were incubated for 2 h at 37 C in 0.5 ml Ham’s F-10 medium with 0.5% bovine serum albumin, 25 DIM Hepes buffer (pH 7.4), and six T3 concentrations, each in triplicate (free T3 from 7 × 10−13 to 5 × 10−11 and 1.5 × 10−8 M). Nuclei were isolated from washed cells in sucrose (0.25 M)-Tris (20 HIM; pH 7.85)-MgCl2 (1.1 HIM) containing 0.5% Triton X-100. Cells took up approximately 5% of the medium T3, and this was not significantly influenced by the T3 concentrations in the medium. About 10% of the cellular T3 was bound to nuclei at 7 × 10−13 M free T3 in the medium. Nuclear binding in the presence of 1.5 × 10-8 M free T3 was approximately 20% of that at 7 × 10−13 M. T4 could...
NEW 1222-TYPE LAYERED CUPRATES (Tl,M)Sr2(Nd,Ce)2Cu2Oz(M = Ti or Nb)

New 1222-type layered cuprates (Tl,M)Sr2(Nd,Ce)2Cu2Oz(M = Ti or Nb) have been successfully synthesized in the pure form and identified by powder X-ray diffraction analyses. The lattice parameters are a=3.847 A and c=29.43 A for (Tl0.8Ti0.2)Sr2(Nd0.75Ce0.25)2-Cu2O9 and a=3.852 A and c=29.45 A for (Tl0.8Nb0.2)Sr2(Nd0.75Ce0.25)2Cu2O9. Resistance measurements showed that they me superconducting at about 40 K.
Immunoregulatory consequences of vitamin deficiencies on background plaque-forming cells in rats.

SummaryBackground hemolytic plaque-forming cells (PFC) directed against three erythrocyte targets were measured in rats with three different, specific vitamin deficiencies: riboflavin, pyridoxine, and pantothenic acid, as well as in control rats. The numbers of background PFC were found to be elevated in all three vitamin-deficiency states compared with controls, whereas earlier studies showed that postimmunization PFC were markedly depressed in those deficiencies tested. The significance of these findings is discussed in terms of a possible loss of suppressor cells.This work was supported by grants from the U.S. National Institutes of Health (1 RO1 HD 08549-01) to A. E. Axelrod, and the Health Research and Services Foundation (R-62) to A. Koros.We thank Dr. T. T. Hayashi, Dr. T. J. Gill, III, and Dr. G. Werner for their special help in this project. We also thank Helen Baginski for technical assistance, and Lorraine Repasky for preparation of the manuscript.
Sensitivity of the resilience of congested random networks to rolloff and offset in truncated power-law degree distributions

Abstract Random networks were generated with the random configuration model with prescribed truncated power-law degree distributions, parameterized by an exponent, an offset, and an exponential rolloff. As a model of an attack, each network had exactly one of its highest degree nodes removed, with the result that in some cases, one or more remaining nodes became congested with the reassignment of the load. The congested nodes were then removed, and the “cascade failure” process continued until all nodes were uncongested. The ratio of the number of nodes of the largest remaining cluster to the number of nodes in the original network was taken to be a measure of the network's resiliency to highest-degree node removal. We found that the resiliency is sensitive to both rolloff and offset (but not to cutoff) in the degree distribution, and that rolloff tends to decrease resiliency while offset tends to increase it.
Progress toward a complete metrology set for the International X-ray Observatory (IXO) soft x-ray mirrors

We present an overview update of the metrologic approach to be employed for the segmented mirror fabrication for the IXO soft x-ray telescope. We compare results achieved to date with mission requirements. This is discussed in terms of inherent capability versus in-practice capability of the metrology. We find that all the needed metrology equipment are in hand but that a number of the needed quantities remain too uncertain relative to mission requirements. This is driven by the mounting of the mirrors themselves. We then discuss some plans for addressing the mirror mounting issues. Finally, we also briefly discuss some promising mandrel metrology techniques.
Statistical thermodynamics of the cluster solid-liquid transition

A direct connection between the solid-liquid transition in atomic clusters and the macroscopic phase transition is established through analysis of the size scaling of the latent heat and transition rounding. The transition occurs without phase separation, leading to remarkable consequences in caloric experiments. These features are all quantified through the characteristic shape of the classical state density, computed by a new Monte Carlo method.
The CgrA and CgrC Proteins Form a Complex That Positively Regulates cupA Fimbrial Gene Expression in Pseudomonas aeruginosa

The CgrA and CgrC proteins of Pseudomonas aeruginosa are coregulators that are required for the phase-variable expression of the cupA fimbrial genes. Neither CgrA nor CgrC resembles a classical transcription regulator, and precisely how these proteins exert their regulatory effects on cupA gene expression is poorly understood. Here, we show that CgrA and CgrC interact with one another directly. We identify a mutant of CgrC that is specifically defective for interaction with CgrA and demonstrate that this mutant cannot restore the phase-variable expression of the cupA fimbrial genes to cells of a cgrC mutant strain. Using this mutant, we also show that CgrC associates with the cupA promoter regardless of whether or not it interacts with CgrA. Our findings establish that interaction between CgrA and CgrC is required for the phase-variable expression of the cupA fimbrial genes and suggest that CgrC exerts its regulatory effects directly at the cupA promoter, possibly by recruiting CgrA. Because the regions of CgrA and CgrC that we have identified as interacting with one another are highly conserved among orthologs, our findings raise the possibility that CgrA- and CgrC-related regulators present in other bacteria function coordinately through a direct protein-protein interaction.
Compact projection optical engine

An optical engine for LCD projection display, to be used in normal lighting has been developed. This system has full color, compact size and good brightness. A metal halide lamp with 1.6 mm arc length and 270 watts was used as light source. The system has been accurately simulated by using ray tracing. In addition to the good color performance, excellent uniformity within 90 percent across the screen was achieved.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A contribution to the chemistry and toxicology of the root of Pbytolacca americana, L.

The extraction of the dried powdered root according to the successive solvent extraction method, the general lead method, and the Stas-Otto method did not establish the presence of an alkaloid, but did establish the presence of the following substances: starch, gum, hemicellulose, sucrose, oxalates, nitrates, steroid materials, and at least one water-soluble saponin. In further search for an alkaloid, the dried powdered root, as well as the expressed juice of the fresh root, was subjected to extensive investigation which embodies various techniques, namely: solvent extraction, precipitation, adsorption, and distillation—with negative results. By pharmacological studies, the toxicity of the root, by elimination, was confined to certain extractives and ultimately led to the acidic steroid sapotoxin, m. p. 212°, the physiological activity of which was correlated in all respects to the reported physiological activity of the root and its crude extract. This crystalline toxic principle was subjected to physical, chemical, and pharmacological examination.
Abnormal Thin Filament Calcium Binding Associated with Cardiac Muscle Diseases Can be Corrected Through TnC Mutagenesis

The Ca2+ sensitivity of cardiac muscle force development can be adversely altered during disease. Since troponin C (TnC) is the Ca2+ sensor for muscle contraction, TnC's Ca2+ binding properties may be affected by the disease related protein modifications. To test this hypothesis, a fluorescent TnC was utilized to measure the Ca2+ binding sensitivity of TnC in the physiologically relevant biochemical model system of reconstituted thin filaments. Consistent with the pathophysiology, the inherited restrictive cardiomyopathy (RCM) mutation TnI R192H and ischemia induced truncation of TnI (residues 1-192) increased TnC's Ca2+ binding sensitivity ∼3 fold and ∼7 fold, respectively; while the dilated cardiomyopathy (DCM) mutation TnT deltaK210 decreased TnC's Ca2+ binding sensitivity ∼ 3 fold. Since the symptoms of the diseases may be caused by the abnormal Ca2+ binding, correcting the Ca2+ binding might improve cardiac function. To achieve this goal, we have engineered TnC constructs with a wide, yet adjustable, range of Ca2+ binding sensitivities by modulating the negatively charged residues in the Ca2+ chelating loop and/or by replacing key hydrophobic amino acids in the regulatory domain of TnC with polar Gln. We were able to correct both the increased and decreased thin filament Ca2+ sensitivities caused by the disease associated proteins via replacing the wild type TnC with specifically engineered TnC constructs. Additionally, engineered TnC constructs can correct the disease related abnormal Ca2+ sensitivity of the acto-myosin ATPase assay and the force-pCa relationship in skinned trabeculae. This study can potentially lead to a novel therapeutic strategy for treating cardiac muscle diseases.
An introduction to neuroepidemiology

Neuroepidemiology is the application of the methods of epidemiology to the problems of clinical neurology. After diagnosis, the most basic characterization of a disease is its frequency. This characterization requires ascertainment of case (numerator) within their population at risk (denominator) to provide incidence, prevalence, and mortality rates. Mortality rates come from government publications, and morbidity rates (incidence and prevalence) from specific field surveys. Definition of the course of illness and identification of risk factors for occurrence or course require specific studies and appropriate statistical testing.
The School-to-College Transition in the Context of Educational Reform: Student Retention and the State Policy Process:

This study examines the impact of state-level educational reform in Kentucky on college student retention. By tracking the educational progress of students who graduated from high school in a large school district and who subsequently enrolled in a research university in the same metropolitan area, the study reveals that the accountability measures and policy tools embedded in the educational reform effort contribute little to the prediction of student retention. The analysis questions the viability of state-driven reforms to improve the retention of students transitioning from high school to college in Kentucky and suggests that high schools and colleges may be able to improve student retention through the development of student information systems that are based on concept of “supply chain management.”
Multiple and long-range participation of benzyl groups in intramolecular C-arylation reactions of benzylated glycosides.

Abstract The intrinsic reactivity of furanosides bearing activated O-benzyl substituents (3-methoxybenzyl), in the presence of bidentate Lewis acids such as tin(IV) chloride, was explored. These glycosides were found to exhibit extremely interesting chemical properties. Thus, with three reactive substituents (at O-2,3,5), the corresponding glycosides (1 and 7) underwent a novel internal bis-C-arylation process, which involved successive alkylations of the benzyl groups at O-2 and O-3 (“multiple participation”), leading to the formal replacement of the two CO bonds at the anomeric center of the glycoside by two CC bonds. The bis-C-arylated constitution of the resulting polycyclic compounds 4 and 8, and the cis configuration of their fused ring system (a tetrahydro-[2]benzopyrano[3,4-d][2]benzoxepin derivative), were determined on the basis of their n.m.r.-spectral parameters. With two 3-methoxybenzyl substituents (at O-3 and O-5, compound 6), intramolecular alkylation of the benzyl group at O-3 or O-5 occurred when glycoside 6 was reacted with titanium(IV) chloride or tin(IV) chloride, respectively, thereby leading to novel bicyclic internal aryl C-glycosides (9 and 12) as major products (“long-range participation”). The constitution of compounds 9 and 12 was unambiguously established by the reactions of analogs of 6 bearing only one 3-methoxybenzyl substituent at a specific position (at O-3: 15; at O-5: 20). The unexpected divergent behavior of 6 in the presence of titanium(IV) and tin(IV) chloride remains to be explained. The availability of compound 9 made it possible to independently prepare the bis-C-arylated derivative 8 (by way of the reverse sequence of internal C-arylation reactions) and thereby to definitively demonstrate its constitution. These unprecedented reactions extend the scope of the intramolecular C-glycosidation of substituted sugars and provide novel methodologies in synthetic carbohydrate chemistry.
Systematic Review of Interventions for Post‐traumatic Headache

Objective Headache is one of the most common physical symptoms after traumatic brain injury (TBI). The specific goals of this review include (1) determination of effective interventions for post-traumatic headache (PTHA), (2) development of treatment recommendations, (3) identification of gaps in the current medical literature regarding PTHA treatment, and (4) suggestions for future directions in research to improve outcome for persons with PTHA. Data Sources Peer-reviewed studies in PubMed, CINAHL, PsycINFO, ProQuest, Web of Science, and Google Scholar: (1) including adult and child samples with mild, moderate, or severe TBI, whiplash, and postconcussion syndrome; (2) with clearly described interventions; (3) with headache treatment as a primary or secondary outcome; (4) published since 1985; and (5) written in English. Study Selection Abstracts from 812 articles from the above searches were reviewed. All research types that studied the treatment of headache after TBI were included, and 64 of the 812 articles appeared to meet the inclusion criteria. Data Extraction The 64 articles were reviewed in full and data were extracted; 36 met all criteria for inclusion. The final 36 articles were rated according to the American Academy of Neurology criteria for classifying therapeutic studies. Data Synthesis No class I studies and only one class II study for the management of PTHA were identified. One class I and one class II study for whiplash-associated disorder with headache as an outcome were identified. Twelve studies met criteria for class III. Conclusions No strong evidence from clinical trials is available to direct the treatment of PTHA. Some guidelines are offered for PTHA management based on primary headache categories and treatments. It is essential that well-designed clinical studies be conducted to inform clinicians on the management and prevention of PTHA chronicity.
Policy review and formulation on substance‐exposed infants

Abstract Attention to the problems of infants exposed to drugs in utero has only recently received public acknowledgement as a social issue that has reached epidemic proportions. Drug abuse is now a primary cause of infant morbidity and mortality. Current data indicates that the occurrence of substance‐exposed infants (SEI) or infants that have been exposed to harmful drugs in utero has been increasing at an alarming rate over the past few years, and, consequentially, there has been a marked rise in the number of such children entering the nation's schools. The scope of the problem can best be described by an overview of some of the current studies. Such an overview is provided herein, along with a review of relevant public policy and recommendations for policy formulation in this area.
DYNAMIC DEPTH REVERSAL STEREOGRAMS

A new stimulus was generated to create dynamic stereopsis. Binocular disparity was alternated between crossed and uncrossed conditions, while mean luminance remained constant, to produce a stereoscopic stimulus that appeared to move continuously in depth. These dynamic depth reversal stereograms provided an effective stimulus to elicit the visual evoked potential (VEP). Neural coding of stereopsis was reflected in the cortical response with YEP amplitudes changing as a function of binocular disparity and of image blur in the stereograms.
Relaxation phenomena and electrical fluctuations in noncrystalline polymers

Abstract A study has been made of electrical fluctuations in PVC, PS and PMMA in the temperature region relating to α and β relaxation processes. Activation energies of the corresponding relaxation transitions and the intervals in keeping with their appearance have been determined. The state of structural disorder of the studied polymers leads to the manifestation of excessive electrical fluctuations during release of molecular mobility of the various kinetic units.
Determination of barium in marine waters by isotope dilution inductively coupled plasma mass spectrometry

Abstract A simple and accurate method is presented for determining barium in marine waters. Equal amounts of an enriched isotope spike and sample are diluted 100-fold with 1% nitric acid. The diluted sample is introduced into an inductively coupled plasma mass spectrometer with a peristaltic pump and the mass region from 135 to 138 is scanned 480 times. The entire procedure takes less than 10 min per sample and is accurate to better than 1% as determined by intercalibration with isotope dilution mass spectrometry.
Methanosaeta, the forgotten methanogen?

Although the aceticlastic methanoarchaea Methanosarcina and Methanosaeta employ different enzymes to catalyze the first step of aceticlastic methanogenesis, it has long been assumed that the remainder of the pathway was the same. Analysis of the recently completed genome sequence of Methanosaeta thermophila confirms that the majority of core steps of the pathway are similar in both genera, but striking differences have been discovered in electron transfer and energy conservation. In addition, the presence of genes encoding enzymes for the CO 2 reduction pathway in the Msa. thermophila genome suggests the possibility that Methanosaeta might be more metabolically diverse than previously thought. Thus, genome analysis of Msa. thermophila presents new research avenues for this forgotten methanogen and reminds us of the questions that still remain unanswered about aceticlastic methanogenesis in both Methanosaeta and Methanosarcina .
Responses of summer flounder, Paralichthys dentatus, embryos to thermal shock

Summer flounder eggs, fertilized artificially, were exposed to time series of abrupt thermal shocks and examined for lethal and sublethal effects. The temperature increments (ΔTs) ranged from 8° to 20°C above the holding temperature, the periods of exposure to the ΔTs were for 2, 4, 8 and 16 minutes. Eggs were exposed at early embryo and late embryo stages of development. The eggs were found highly resistant to thermal shock, early embryo stage eggs survived the highest temperature-time exposure used, at ΔT 20°C for 16 minutes; late embryo stage eggs showed significantly increased mortalities in the region of ΔT 16° C for 16 minutes and ΔT 18° C for 2 minutes and at all higher temperature exposures. Larvae hatching from the late embryo stage eggs after thermal shock were examined for anomalous anatomical development. A pattern of increasing incidence of developmental anomalies appeared at ΔT 14°C after exposures of between 4 and 8 minutes. Such sublethal effects probably lead quickly to larval death from starvation, predation, etc., and must be taken into consideration in assessing effects of thermal shock.
Sequence analysis of human J chain. Amino terminal location of a disulfide bond linking the immunoglobulin heavy chain.

Abstract Carboxyamidomethylated J chain was shown to be an excellent substrate for the enzyme, pyrollidone carboxylyl peptidase, which specifically removed the cyclized amino terminal glutamyl residue. J chain lacking the “blocked” PCA group was subjected to automated Edman degradation and the amino terminal amino acid sequence determined as: PCA-Glu-Asp-Glu-Arg-Ile-Val-Leu-Val-Asp-Asn-Lys-CMCys-Lys-CMCys-Ala-Arg. Previous studies by others have identified a disulfide bridge between the heavy chain of immunoglobulins and a tripeptide identical in composition with the sequence at positions 15–17 in the J chain. These two sets of data locate the linkage of immunoglobulin heavy chain with Cys 15 of the J chain.
Rapid Cycling Valve for 30-HZ Pulsed H- Ion Source

This valve is used to reduce the gas loading on the vacuum system of a multipulsing H- ion source. It is a self-aligning chopper type. A mechanism of this construction assures the reilability required for an ion source of this nature. The reliability of this mechanism is due to the fact that the disc of the chopper is rotated at a relatively slow constant velocity and no wearing parts of the assembly are subjected to the extreme vacuum atmosphere. The entire valve assembly is very simple in construction. It is driven with a synchronous motor to keep it in step with the accelerating frequency. Vacuum integrity is maintained with the use of a ferromagnetic fluid coupling as part of the drive system. All bearings, motors, and drive mechanisms are external to the vacuum cavity.
Tested Performance of Photovoltaic Array Optimization Technologies

Growth in the solar industry continues as the cost of photovoltaic power is approaching grid parity. Several technologies have been developed that address reductions in power production associated with partial shading of panels, mismatch at the panel and string levels, and multiple array orientations, conditions that often arise in residential installations. In the absence of existing testing standards, a methodology was developed to evaluate performance of power optimization devices under shading conditions. Technologies investigated include buck-boost, parallel voltage boost, and impedance matching. Performance improvements range from negligible to a 44% increase in energy delivered under partial shading. Comparison data is presented along with guidance for selecting among the different technologies currently available on the market.Copyright © 2012 by ASME
On the relation between the hellmann energy functional and the ground state energy of anN-fermion system

The Hellmann energy functional is derived from the Schrodinger variational principle. It is shown to be an upper bound on the ground state energy of anN-fermion system. Its limiting behaviour for small and large particle numbers is discussed.
Effect of adding temozolomide to radiation therapy on the incidence of pseudo-progression

Recently, there has been greater awareness that combination radiation and temozolomide used to treat glioblastomas may cause increased contrast enhancement on the first post radiation MRI scan. However, this increased enhancement may stabilize or decrease over time and represent pseudo-progression (psPD) rather than true progressive disease. It has never been shown that this phenomenon is greater with combination therapy than radiation alone. To address this question, we reviewed MRI scans in glioblastoma patients treated with radiation alone versus patients treated with radiation and concomitant temozolomide and compared the frequency of psPD in the two groups. Eighteen of 47 patients (38%) treated with radiation alone demonstrated enlargement on their first post-radiation MRI scan and 11 of these 18 (61%) proved to have psPD as defined by no further enlargement on stable therapy for 3 months following radiation. Twenty-four of 45 patients (53%) treated with radiation and temozolomide had enlargement on their first post-radiation MRI scan and 13 of these 24 (54%) had psPD. Median overall survival (OS) in patients with psPD treated with radiation alone was 15.6 versus 12.8 months in those without psPD. Median OS in patients treated with radiation and concomitant temozolomide who had psPD was 24.4 versus 15.9 months in those who did not have psPD. We were unable to detect a difference in OS between the four groups. Presence of psPD, independent of treatment, was associated with prolonged progression-free survival (P = 0.05) but not OS. psPD may be more common in combination therapy but most likely by a small margin.
Life extension of blackwater and eddy county HVDC converter stations

High voltage direct current (HVDC) converter stations and transmission lines represent a significant investment and source of revenue for the electric utilities owning them. Many installations are approaching or exceeding 30 years of service. In most cases, the transmission path provided by operating HVDC converter stations is not only profitable but is needed for reliability; life extension is not an option, it is a necessity.
A platinum(IV) complex oxidizes guanine to 8-oxo-guanine in DNA and RNA.

A platinum(IV) complex with a high reduction potential, d,l-1,2-diaminocyclohexyltetrachloroplatinum(IV) (PtIV(dach)Cl4), oxidizes guanine in guanosine-5‘-monophosphate (GMP), 2‘-deoxyguanosine-5‘-...
How useful are B-type natriuretic peptide measurements for monitoring changes in patent ductus arteriosus shunt magnitude?

How useful are B-type natriuretic peptide measurements for monitoring changes in patent ductus arteriosus shunt magnitude?
Defect generation in InGaN/GaN light-emitting diodes under forward and reverse electrical stresses

Abstract Electrical and optical degradations of GaN/InGaN single-quantum-well light-emitting diodes (LEDs) under high-injection current (150 A/cm2) and reverse-bias (−20 V) stresses were investigated. A substantial increase in the tunneling components of both forward and reverse currents was observed in the devices subjected to reverse biases. However, the stressed LEDs exhibited minimal degradation of optical characteristics. For devices subjected to high forward currents, a monotonic decrease in light intensities with stress time, accompanied by an increase of forward leakage current, was observed in the low-injection region, but a positive stress effect was found on the light output measured at high currents. These degradation behaviors can be explained by slow generation of point defects in the LEDs via different mechanisms, i.e., thermally induced defect formation in the InGaN active region in the devices subjected to high-injection currents, and destructive microstructual changes as a result of impact ionization in the cladding layer in the devices under high reverse-bias stress.
Conducting Statistical Tests of Hypotheses: Five Common Misconceptions Found in Transportation Research

Most statistical methods use hypothesis testing. Analysis of variance, regression, discrete choice models, contingency tables, and other analysis methods commonly used in transportation research share hypothesis testing as the means of making inferences about the population of interest. Despite the fact that hypothesis testing has been a cornerstone of empirical research for many years, various aspects of hypothesis tests commonly are incorrectly applied, misinterpreted, and ignored—by novices and expert researchers alike. On initial glance, hypothesis testing appears straightforward: develop the null and alternative hypotheses, compute the test statistic to compare to a standard distribution, estimate the probability of rejecting the null hypothesis, and then make claims about the importance of the finding. This is an oversimplification of the process of hypothesis testing. Hypothesis testing as applied in empirical research is examined here. The reader is assumed to have a basic knowledge of the role of...
The cataphoric use of the indefinite this in spoken narratives

Are concepts that were introduced with the unstressed, indefinite articlethis, as opposed to the indefinitea/an, more accessible from listeners’ mental representations? Subjects heard and then verbally continued each of a series of informal narratives. The last clause of each narrative introduced a new noun phrase that began with either the indefinitethis or the indefinitea/an (e.g.,this egg oran egg). When the concepts were introduced with the indefinitethis, the subjects referred to them more frequently, often within the first clauses that they produced, and typically via pronouns. In contrast, when the concepts were introduced witha/an, the subjects referred to them less frequently and typically via full noun phrases. Thus, concepts introduced with the indefinitethis were more accessible; therefore, the indefinitethis appears to operate cataphorically to improve referential access.
Microvascular Arterial Bypass Surgery: Long-Term Outcomes Using Validated Instruments

Purpose: Penile microarterial bypass surgery may be the only treatment capable of restoring normal erectile function without the necessity of chronic use of vasoactive medications or placement of a penile prosthesis. Lack of standardization in patient selection, hemodynamic evaluation, surgical technique and limited long-term outcome data using validated instruments have resulted in this surgery being considered experimental. In this study we report long-term outcome data using validated questionnaires in young men (younger than 55 years) free of vascular risk factors who underwent microvascular arterial bypass surgery.Materials and Methods: This is a single institution retrospective institutional review board approved study of 71 men (mean age 30.5 ± 9.2 years) who underwent microvascular arterial bypass surgery between 1996 and 2007 (mean followup 34.5 ± 18 months).Results: Mean preoperative and postoperative penile rigidity measures with and without phosphodiesterase type 5 inhibitors were 41%, 77% and...
An Epi-Detected Coherent Anti-Stokes Raman Scattering (E-CARS) Microscope with High Spectral Resolution and High Sensitivity

We report an epi-detected coherent anti-Stokes Raman scattering (E-CARS) microscope that uses two synchronized picosecond pulse trains. The microscope not only provides high spectral resolution but also significantly improves sensitivity for three-dimensional vibrational imaging of living cells.
Effects of variations in carbonate chemistry on the calcification rates of Madracis auretenra (= Madracis mirabilis sensu Wells, 1973): bicarbonate concentrations best predict calcification rates

Physiological data and models of coral calcification indicate that corals utilize a combination of seawater bicarbonate and (mainly) respiratory CO2 for calcification, not seawater carbonate. However, a number of investigators are attributing observed negative effects of experimental seawater acidification by CO2 or hydrochloric acid additions to a reduction in seawater carbonate ion concentration and thus aragonite saturation state. Thus, there is a discrepancy between the physiological and geochemical views of coral biomineralization. Furthermore, not all calcifying organisms respond negatively to decreased pH or saturation state. Together, these discrepancies suggest that other physiological mechanisms, such as a direct effect of reduced pH on calcium or bicarbonate ion transport and/or variable ability to regulate internal pH, are responsible for the variability in reported experimental effects of acidification on calcification. To distinguish the effects of pH, carbonate concentration and bicarbonate concentration on coral calcification, incubations were performed with the coral Madracis auretenra (= Madracis mirabilis sensu Wells, 1973) in modified seawater chemistries. Carbonate parameters were manipulated to isolate the effects of each parameter more effectively than in previous studies, with a total of six different chemistries. Among treatment differences were highly significant. The corals responded strongly to variation in bicarbonate concentration, but not consistently to carbonate concentration, aragonite saturation state or pH. Corals calcified at normal or elevated rates under low pH (7.6‐7.8) when the seawater bicarbonate concentrations were above 1800lM. Conversely, corals incubated at normal pH had low calcification rates if the bicarbonate concentration was lowered. These results demonstrate that coral responses to ocean acidification are more diverse than currently thought, and question the reliability of using carbonate concentration or aragonite saturation state as the sole predictor of the effects of ocean acidification on coral calcification.
Analyzing Resilience to Node Misbehaviors in Wireless Multi-Hop Networks

The network resilience has been studied as a fault tolerance measure in wired networks for decades; however, little effort has been made to analyze the resilience of wireless multi-hop networks, especially in the presence of misbehaving nodes. In this work, we study such a problem: whether there exists an overlay achieving "strong" resilience when misbehaving nodes are present in the underlying wireless multi-hop network. To address this problem, we first introduce two new metrics, k-connected survivability and resilience capacity. The former metric is used to measure the network connectivity probabilistically; while the latter one is used to evaluate the ability of accommodating misbehaving nodes deterministically. We then derive an approximate representation of the k-connected survivability, and provide the close-form representations of resilience capacity for k = 1 and k = 2 and a heuristic algorithm to calculate it when k ges 3. Finally, based on our analytical results, we prove that an overlay can achieve the derived resilience by satisfying three conditions: (i) containing all and only cooperative nodes of the original network; (ii) keeping the minimum cooperative degree at least k; (iii) having Theta (log2 N) neighbors of each node in average.
An economic evaluation of freeway service patrols

Highway assistance services, also called the freeway service patrols (FSPs), are one of the main approaches used by incident management programs. The objective of this study was to investigate the factors that contribute to people choosing to rely on the highway assistance services (FSP) in comparison to private assistance services such as the Automobile Association of America (AAA). Further the effectiveness of the Freeway Service Patrol was studied by carrying out a benefit-cost analysis using Los Angeles as a test case. The results indicate that the probability that an individual would choose to depend on the highway assistance services depends on the key attributes like the annual fee of the program, the fee at the time of assistance, the time of waiting for assistance and cost of breakdown. The B/C ratio for the Los Angeles FSP was calculated to be 5.91.
Analytical parametric study on horizontal loading capacity of suction piles

An analytical parametric study has been conducted to identify the relative significance of several pertinent parameters that are thought to govern the horizontal loading capacity of suction piles. The parameters studied include: the point of horizontal load application, diameter of flange, pile diameter, seafloor soil strength, pile diameter to length ratio, and layered soil properties. Results of the analytical parametric study on each parameter are summarily included and discussions are provided, which can be used in the future for the optimum design of suction piles.
Isolation and Characterization of Xenorhabdus nematophila Transposon Insertion Mutants Defective in Lipase Activity against Tween

We identified Xenorhabdus nematophila transposon mutants with defects in lipase activity. One of the mutations, in yigL, a conserved gene of unknown function, resulted in attenuated virulence against Manduca sexta insects. We discuss possible connections between lipase production, YigL, and specific metabolic pathways.
Residence time distributions in systems governed by the dispersion equation

Abstract The theories of discrete and continuous random walks have been applied to systems governed by the dispersion equation. It is shown that residence time distributions can be defined and determined at a particle level of scrutiny and that the resulting distributions are identical to those obtained using continuum methods. Now, however, the appropriate boundary and initial conditions are apparent; and the resulting solutions can he given a clear physical interpretation. The long-sought residence time distribution for dispersion in an open system is shown to be the same as that in a closed system. This result is consistent with Danckwerts' formulation for the yield of first order reactions but invalidates recent results which were based on a transfer function approach to residence time distributions.
Thermoelectric performance of PbSe quantum dot films.

The thermoelectric (TE) performance of films of colloidal lead selenide (PbSe) quantum dots (QDs) with metal-chalcogenide complex ligands is seen to change with QD size and temperature. Films of smaller QDs have higher Seebeck coefficient magnitudes, indicating stronger quantum confinement, and lower electrical and thermal conductivities. The thermoelectric figure of merit ZT is ∼0.5 at room temperature and increases with temperature to 1.0–1.37 at ∼400 K, where it is larger for smaller QD films. This is better than previous results for solution-prepared QD TE materials at these elevated temperatures.
All-optical, continuously tunable, nanosecond pulse delay using wavelength conversion and fiber dispersion

We demonstrate an all-optical tunable delay based on wavelength shifting in a fiber- parametric amplifier followed by a dispersive fiber. The device operates near 1550 nm and generates delays as large as 1.2 ns.
Cirrus clouds and the large-scale atmospheric state: Relationships revealed by six years of ground based data

Abstract The properties of cirrus clouds observed at the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) in Oklahoma are documented from a nearly continuous 6-yr record of 35-GHz cloud radar data. Cirrus frequency over the ACRF is 23% and 28% of the time in the warm (May–September) and cold seasons (November–March), respectively, with maxima and minima during the period studied of 30% and 16% in the warm season and 34% and 24% in the cold seasons. Cirrus, as defined here, reveal a seasonal oscillation in their macroscale properties that can be traced to the seasonal deepening of the troposphere in the Southern Plains region. While the average bulk microphysical properties do not change significantly from season to season, the variability of certain parameters demonstrates seasonal change. It is shown that the properties of cirrus clouds vary perceptively with the large-scale vertical motion. Using NCEP–NCAR reanalysis data to define the large-scale meteorological state when cirrus...
When Moving Up Implies Moving Out: Rural Adolescent Conflict in the Transition to Adulthood.

This paper examines the influence of community context on the attitudes of rural and nonrural adolescents toward their own future geographic and social mobility. Part of a national sample in a longitudinal study of career development, the 1,060 subjects were public school students in grades 6, 8, 10, and 12 from 3 contrasting Illinois communities. Subjects completed questionnaires based on those used in the National Educational Longitudinal Study (NELS), and some also participated in the experience sampling method for obtaining self-reports on activities and moods. Some analyses were replicated using NELS data. Hypotheses were that rural adolescents would be more likely than their nonrural counterparts to have future residential preferences that would be incompatible with their career aspirations, and that the resulting conflict would lead to uncertainty and negative affect regarding the future. Questionnaire data revealed a greater prevalence among rural than among nonrural adolescents of a potential conflict between the perceived importance of staying close to parents and relatives and moving away from their area. Those adolescents expressing this potential conflict were more likely to indicate feeling empty, angry, and pessimistic about their futures. Compared to urban and suburban students, rural adolescents (particularly rural males) expressed more hesitancy about pursuing further education, more anger about their futures, and more worry and lower motivation when doing activities related to their future goals. Contains data tables, figures, and 16 references. (Author/SV) *********************************************************************** Reproductions supplied by EDRS are the best that can be made * from the original document. *********************************************************************** When Moving Up Implies Moving Out: Rural Adolescent Conflict in the Transition to Adulthood Joel Hektner University of Chicago "PERMISSION TO REPRODUCE THIS MATERIAL HAS BEEN GRANTED BY
An evaluation of directory schemes for cache coherence

The problem of cache coherence in shared-memory multiprocessors has been addressed using two basic approaches: directory schemes and snoopy cache schemes. Directory schemes have been given less attention in the past several years, while snoopy cache methods have become extremely popular. Directory schemes for cache coherence are potentially attractive in large multiprocessor systems that are beyond the scaling limits of the snoopy cache schemes. Slight modifications to directory schemes can make them competitive in performance with snoopy cache schemes for small multiprocessors. Trace driven simulation, using data collected from several real multiprocessor applications, is used to compare the performance of standard directory schemes, modifications to these schemes, and snoopy cache protocols.
Night and Day in the VA: Associations Between Night Shift Staffing, Nurse Workforce Characteristics, and Length of Stay

In hospitals, nurses provide patient care around the clock, but the impact of night staff characteristics on patient outcomes is not well understood. The aim of this study was to examine the association between night nurse staffing and workforce characteristics and the length of stay (LOS) in 138 veterans affairs (VA) hospitals using panel data from 2002 through 2006. Staffing in hours per patient day was higher during the day than at night. The day nurse workforce had more educational preparation than the night workforce. Nurses' years of experience at the unit, facility, and VA level were greater at night. In multivariable analyses controlling for confounding variables, higher night staffing and a higher skill mix were associated with reduced LOS.