cssi/SciSciGPT-SciSciNet huggingface dataset:
The Influence of Pregnancy on the Blood Pressure Effects of Histamine in Normotensive and Spontaneously Hypertensive Rats

The blood pressure responses of normotensive (WKY) and hypertensive (SHR) rats to histamine injections were compared before and during pregnancy. A series of increasing doses of intravenous histamine was given before histamine receptor blockade, after H1 (pyrilamine) block, and after combined H1 and H2 (cimetidine) block. In both WKY and SHR nonpregnant rats, histamine caused dose-dependent decreases in blood pressure which were partially dependent on H1 and H2 receptors. In late pregnancy, the magnitudes of the hypotensive effects of histamine were significantly reduced and blocked only by combined H1 and H2 treatment but not by H1 treatment alone. Thus, the blood pressure effects of exogenous histamine in normotensive and hypertensive rats are modified in a similar way during late pregnancy with diminished hypotensive effects which are more dependent on H2 receptors than the effects in nonpregnant rats. This change in histamine responsiveness may play a role in the cardiovascular adjustments of pregnancy.
EXPERIMENTAL STUDIES ON THE HYPOPHYSIS CEREBRI 1. THE EFFECT OF SINGLE PREGNANCY IN THE ALBINO RAT

The initial observation that the pituitary gland varies in size and histologic structure during pregnancy was first reported in 1899 by Comte (1), who described a hypertrophy and hyperplasia in the human hypophysis. Other investigators, Launois and Mulon (2), Mayer (3), Alin (4). and Biedl (5), on human material, agree with the classical observations of Erdheim and Stumme (6), namely, that during pregnancy the gland increases in size. In addition, the latter maintained that while in the nullipara the chief cells or chromophobes are less abundant than the chromophilie cells, during pregnancy an increase in the number of chief cells occurs with a simultaneous change in their histologic character to such an extent that they should be spoken of as a new cell-type, the pregnancy cell (Schwangerschaftszelle). Biederman (7) decided that they are weakly basophilic. After termination of pregnancy, an involution of the pregnancy cells occurs, and they revert back, for the most part, to their old structure.
The Effects of Trait Driving Anger, Anonymity, and Aggressive Stimuli on Aggressive Driving Behavior

We examined the effects of trait driving anger, aggressive stimuli, and anonymity on aggressive driving behavior in a driving simulation task. High and low driving anger participants were randomly assigned to one of four conditions: (a) anonymous vs. identifiable driver; and (b) exposure to aggressive stimuli versus nonaggressive stimuli. Participants drove more aggressively when they were anonymous (d = .28) and exposed to aggressive stimuli (d = .05). Males drove more aggressively than did females (d = .06). No main or interaction effects were found for trait driving anger (road rage). Results suggest that situational factors affecting other forms of aggression are also important in aggressive driving.
Petrogenesis of the Conejo volcanic suite, southern California: Evidence for mid-ocean ridge–continental margin interactions

The evolution of the southern California Borderland during mid-Miocene time was dependent on the interactions between the North American continent and the converging East Pacific Rise. Evidence from geological and geochemical investigations of the Conejo volcanic suite, whose petrogenesis is linked to these interactions, suggests an intimate relation between the subducting ridge and the volcanic rocks. The whole-rock chemistry of this suite (K2O < 0.4%; 87Sr/86Sr = 0.70248–0.70372, average = 0.70306; TiO2 = 1.2%–1.8%) and restricted range of pyroxene and plagioclase compositions support a model in which active ridge volcanism, fractionation, and mixing of primitive liquids with later differentiates can account for the observed petrologic evolution. The interaction of the ridge with the subduction zone may result in the cessation of subduction, the preferential subduction of the trenchward ridge flank, or localized volcanism in the vicinity of the ridge–subduction zone intersection.
Siderophile-rich magnetic spheroids from the Cretaceous-Tertiary Boundary in Umbria, Italy

The magnetic fraction of some Cretaceous–Tertiary (K–T) boundary sediments sampled at two locations in Italy, contains a spheroidal component which has retained some relict mineral textures and, possibly, mineral chemistry from the K–T event. The spheroids contain small crystals (1–50 µm) of magnetite in a highly altered groundmass. These crystals are commonly skeletal, indicating formation by rapid growth from a high-temperature liquid. Variable concentrations of Ni, Mg and Al (differing by at least a factor of 5) in the magnetite may also reflect a relict chemistry. These spheroids contain higher concentrations of Ir and probably other siderophiles than the bulk sediment and may have been an important carrier for these elements at 65 Myr. This discovery supports evidence for a major accretionary event at the end of the Cretaceous.
Solubilization of Naphthalene by Sodium Cholate and Pattern of Self- Association of Sodium Cholate in 0.15 M Sodium Chloride

Naphthalene solubility was determined in aqueous 0.15 M NaCl containing sodium cholate in the 0-0.05 M concentration range at 25 +/- 0.1 degrees. Sodium cholate tends to self-associate in aqueous solutions. Most often, the association pattern has been described in terms of a monomer-micellar model in which it is assumed that no association occurs below the critical micelle concentration. By comparison of the experimental solubilization curve with curves calculated on the basis of the monomer-micellar model, it was shown that this model is inappropriate for the self-association pattern of sodium cholate. The solubility data were consistent with a model that assumes that sodium cholate associates to form dimers, trimers, and higher aggregates with an average aggregation number of 7.63. Model calculations suggest that naphthalene is solubilized by dimers and higher aggregates. Solubilization of naphthalene by trimers appears to be negligible.
Domain capacitance tuning of Gunn oscillators

Measurements of the effects of applied bias, temperature, and load resistance on Gunn oscillator performance have been made. Broad-band frequency tuning and mode switching has been observed which can be related to changes of domain capacitance with applied voltage and temperature.
Band structure of cubic NaxWO3

Abstract The band structures of cubic WO3 and NaWO3 have been calculated, and they are shown to be nearly identical, demonstrating the validity of the rigid band model for different sodium concentrations. To elucidate the nature of the bonding, the density of states is decomposed into its s, p, and d contributions from each atomic site.
Double-blind comparison of 2% ketoconazole cream and placebo in the treatment of tinea versicolor

Malassezia furfur (Pityrosporum orbiculare) was confirmed by microscopic potassium hydroxide (KOH) examination in 101 patients with recurring lesions of tinea versicolor. In a double-blind comparative study, patients were randomly assigned to once-daily ketoconazole 2% or placebo create. At the end of treatment, 98% (p A 0.0001) of the patients using ketoconazole and 28% of those using placebo responded clinically (healed or had mild residual disease). There was an overall 84% mycologic cure rate (negative KOH at treatment end) for patients using ketoconazole 2% create and 10% for those using placebo cream (p A 0.0001). Ketoconazole-treated patients who were cured at the end of treatment remained cured 8 weeks later. By contrast 75% of those responding to placebo had relapsed by the 8-week follow-up visit. Follow-up after 2 years revealed that 79% (38/48) of the patients treated with ketoconazole remained clear 12 or more months.
Equilibrium behavior of an isotropic polyelectrolyte gel model of the tectorial membrane: effect of pH.

Abstract An isotropic polyelectrolyte gel model ( Weiss and Freeman, 1996a ) of the tectorial membrane (TM) was extended to incorporate the effect of pH. The effect of pH is analyzed in order to interpret measurements of the effect of pH on the dimensions of the TM ( Freeman et al., 1996a ). The pH dependence of the model results from the binding of hydrogen ions to TM macromolecules – to both neutral sites with basic p K and negatively charged sites with acidic p K . Parameters of the model can be based on estimates of the concentration in the TM of collagen and glycosaminoglycans (GAGs), two identified constituents of the TM that account for approximately 40% of its dry weight. The resulting model shows swelling responses at both high and low pH that are qualitatively similar to the measurement on the TM but that differ quantitatively. Alternatively, parameters of the model can be chosen in an ad hoc fashion to closely fit the measurements of TM swelling as a function of pH. Taken together these results suggest that either estimates of the collagen and GAG content of the TM are in error or constituents of the TM, which have not yet been identified, contain appreciable pH-dependent fixed charge and contribute to the swelling behavior of the TM.
Endoscopic retrograde cholangiopancreatography and the pancreas: when and why?

Since its development in the 1970s, endoscopic retrograde cholangiopancreatography (ERCP) has occupied a unique position as a diagnostic modality for the pancreas and as a therapeutic technique. 26 Traditionally, ERCP has been the gold standard in defining pancreatic duct anatomy and identifying chronic pancreatitis and pancreatic cancer. With the new, powerful diagnostic modalities available, excellent morphologic information of the pancreas can be obtained with CT scanning, MR imaging, and endoscopic ultrasonography (EUS). ERCP has a complementary morphologic role and offers unique diagnostic information, such as sphincter of Oddi function, and therapeutic application. This article provides an overview of the uses of ERCP for benign pancreatic disorders and the role of ERCP in pancreatic cancer. In patients presenting with acute, recurrent pancreatitis or chronic pancreatitis, diagnostic ERCP may be used to identify a cause or complication or to define anatomy before surgical intervention. 14 Therapeutic ERCP can be used to prevent recurrent attacks caused by anatomic abnormalities or to alleviate acute or chronic pain. The goal of endoscopic treatment can be temporary relief of symptoms or definitive treatment.
A physiological and structural study of neuron types in the cochlear nucleus. II. Neuron types and their structural correlation with response properties.

The present study examined the morphological cell types of neurons labeled with intracellular horseradish peroxidase injections, many of them following electrophysiological recordings in the cochlear nucleus of gerbils and chinchillas. Most of the subdivisions and neuronal types previously described in the cat were identified in the present material, including spherical and globular bushy cells, stellate, bushy multipolar, elongate, octopus, and giant cells in the ventral cochlear nucleus, and a cartwheel cell in the dorsal cochlear nucleus. In many cases these structurally distinct neurons were correlated with their characteristic responses to stimulation by sound or intracellular injection of depolarizing current. The dendritic terminals of the elongate, antenniform, and clavate cells of the posteroventral cochlear nucleus link each of these cell types with neighboring structures in distinct patterns, which may provide a basis for differences in synaptic organization. These cell types differ from each other and from the stellate cells of the anteroventral cochlear nucleus. Despite their heterogeneous morphology, most of these neurons had a regular discharge in response to stimulation (choppers). Irregularly firing neurons (primary-like) had very different structures, e.g., the spherical and globular bushy cells and the bushy multipolar neuron. They, too, represent a heterogeneous population. An onset neuron was identified as an octopus cell. This paper compares the morphological observations with the electrophysiological properties of different cell types reported in a companion paper (Feng et al. [1994] J. Comp. Neurol.). Together, these findings imply that response properties may be partially independent of neuronal structure. Morphologically distinct neurons can generate similar temporal patterns in response to simple acoustic stimuli. Nevertheless, the synaptic organization of these different neuron types, including their connections, would be expected to affect or alter the cells' responses to appropriate stimuli. The possibility is raised that membrane properties and synaptic organization complement and interact with each other.
Developmental regulation of re-uptake of phosphatidylcholine by type II alveolar epithelium

Type II alveolar epithelia produce, store and secrete pulmonary surfactant, a phospholipid and protein mixture which stabilizes alveoli at low lung volumes and, thereby, prevents alveolar collapse. We determined the developmental changes in the uptake, metabolism and reutilization of surfactant-related phospholipid in primary cultures of type II cells derived from fetal rat lung. Primary cultures of fetal and neonatal type II cells were incubated in media containing labelled liposomes. After the incubation phospholipids were extracted from the cells and uptake of label was analyzed. Re-uptake of radiolabelled dipalmitoyl phosphatidylcholine (DPPC) was concentration-dependent in undifferentiated fetal cells, differentiated fetal cells and neonatal cells. Re-uptake of DPPC by undifferentiated fetal cells was lower than re-uptake by both differentiated fetal and neonatal cells at 15 and 75 microM PC. Binding of DPPC to the cell surface involved a protein interaction, since trypsin was able to dissociate this trypsin-releasable fraction from internalized label. Undifferentiated fetal, differentiated fetal and neonatal cells all exhibited approx. 50% metabolic degradation of internalized phospholipid. Degraded lipids were reutilized in the synthesis of phosphatidylglycerol, but neonatal cells resynthesized twice as much phosphatidylglycerol as did undifferentiated fetal cells. These are the first studies which show that morphologically undifferentiated fetal type II cells are capable of the uptake of surfactant phospholipid as well as the degradation and reutilization of internalized phospholipid. Re-uptake, degradation and reutilization of internalized phospholipid appear to be under developmental control.
Electron microscopy of matrix formation and calcification in rat enamel

Abstract Enamel from incisors and molars of 4-day, 10-day and 1-year old rats has been cut with a diamond knife, as non-decalcified ultra-thin sections, and examined by electron microscopy and diffraction, with the following findings: 1. (1) Enamel matrix elaboration starts in the ameloblastic cytoplasm, next to the amelo-dentinal junction membrane. Fibrogenesis occurs in two steps: first by an elaboration of diffusely scattered fibrillar protein bundles, embedded in ground substance; secondly, by the appearance of elongated ovoid or frequently cord-like structures, which by coalescence form the enamel matrix. When completed, the fibrillar matrix assumes a three-dimensional reticular appearance. 2. (2) The apatite crystal growth starts selectively within and on the longitudinal fibrils of the reticulum, in the form of small crystallization centres, which later fuse together, giving rise to strips of calcifying fibrils. Grouping of adjacent calcifying fibrils is followed by partial and then complete fusion, ultimately forming adult apatite crystals, which contain in their core calcified protein fibrils. These crystals take the shape of elongated hexagonal prisms. 3. (3) In the rat incisor, matrix differentiation and calcification of enamel proceeds progressively from the enamel-dentine junction toward the enamel surface. Three distinct layers can be recognized: inner, middle and outer enamel. The narrow inner and outer enamel contain aggregates of parallel oriented apatite crystals, without any distinct rod structure, whereas the wider middle enamel exhibits a complicated rod interrelationship characterized by alternating layers of rods running in different directions. 4. (4) In adult rat teeth, a difference in apatite crystallization has been noted both in incisor and molar enamel which is characterized by zones of well-formed apatite crystals intermixed with zones of unfused calcified fibrils.
A Virtuous Circle: Political Communications in Postindustrial Societies By Pippa Norris. Cambridge: Cambridge University Press, 2000. 398p. $59.95 cloth, $21.95 paper.

Scholars of media and public opinion in Western Europe and the United States will find plenty of useful information and much to argue about in A Virtuous Circle. The data are rich and broad, and the conclusions drawn are provocative and relevant to some of the major debates in the field. The central question addressed is whether the news media discourages political engagement.
Natural channel design impacts on reach scale transient storage

Abstract Natural channel design stream restoration projects frequently use river steering structures to establish stable planform and meander bend morphology as well as to enhance aquatic ecosystem habitat. This research examined the impact of restoration on aquatic ecosystem function by quantifying transient storage, an important component of hydrologic retention in biogeochemically active zones, in nine restored reaches and seven non-restored reaches in the Finger Lakes and Catskill Mountain regions of New York State. Slug injections of a conservative tracer (Cl−) were used to obtain breakthrough curves at downstream locations in each reach. Reach-scale transient storage areas, exchange flux, and residence times were estimated by simulating the observed tracer breakthrough curves with the one-dimensional transport with inflow and storage (OTIS) model. Velocity transects delineated larger normalized surface storage areas in the restored reaches than in non-restored reaches due to large slow moving eddies below river steering structures. The median of OTIS estimated normalized storage area was 33% larger in restored reaches than in non-restored reaches. Median exchange flux was 105% larger while median residence time was 15% smaller in restored reaches than in non-restored reaches. These results suggest restored reaches are dominated by relatively fast surface transient storage exchange while non-restored reaches have less surface transient storage exchange and may be dominated by shallow hyporheic exchange along the bed.
Photoluminescence investigation of InAs quantum dots incorporating DWELL structures on patterned and planar GaAs (100) substrate

InAs quantum dots embedded in InGaAs quantum well (DWELL) structures grown by metal-organic chemical-vapor deposition on nano-patterned GaAs pyramids and planar GaAs (001) substrate are comparatively investigated. Photoluminescence (PL), PL excitation, and time-resolved PL measurements demonstrate that the DWELL grown on the GaAs pyramids has a broad QW PL band (FWHM ~ 90 meV) and a better QD emission efficiency than the DWELL structure grown on the planar GaAs (001) substrate. These properties are attributed to the InGaAs QW with distributed thickness profile on the faceted GaAs pyramid, which introduces tapered energy band structure and assists the carrier capture into the QDs. This research provides useful data for further improving the performance of DWELL structures for device applications.
Calcium concentration and the exudation of sugars from pegs and fruits of axenic peanut plants

Abstract Higher populations of total fungi, bacteria and actinomycetes occur in the geocarposphere of peanuts than in bulk soil. One of the factors that affects exudation of organic substrate is Ca 2+ concentration in the pegging medium. Plants of Arachis hypogaea L. cv. Argentine were grown axenically and the effect of three concentrations of Ca 2+ on exudation of sugars from excised fruits at different stages of development was measured. The amount of total sugar exuded was greatest at 10 mg Ca 2+ 1 −1 in the bathing solution after 48 h. More sugar was exuded from peg sections than from older fruits and the difference depended upon whether results were expressed as mg sugar g −1 fruits or μg per fruit. Of the three sugars exuded the quantities decreased in the order sucrose, fructose, and glucose.
The pneumostome rhythm in slugs: A response to dehydration controlled by hemolymph osmolality and peptide hormones

1. One response of the terrestrial slug, Limax maximus to dehydration is the initiation and modulation of the pneumostome rhythm. When a slug has lost 15-20% of its initial body weight by evaporation, the frequency of pheumostome closures, which is less than 0.5 closures/min in fully hydrated slugs, begins to increase. 2. The frequency increases with further dehydration, but the average duration of each closure remains constant. Thus, the proportion of time during which the pneumostome is closed increases. Simultaneously, the area of the pneumostome opening decreases. 3. This behavior appears to be controlled in part by both the osmolality of the slug's hemolymph and by a peptide closely related to arginine vasotocin (AVT) and arginine vasopressin (AVP). Injecting intact slugs with mannitol, which increases the osmolality of the hemolymph, or with AVT or AVP, can initiate the pneumostome rhythm. 4. Mannitol injections, however, do not provoke the decrease in the area of the pneumostome opening which is induced by natural dehydration or by AVT or AVP injection. This suggests that at least two systems may be involved in the overall control of the pneumostome.
Crosswalk between DSM-IV dependence and DSM-5 substance use disorders for opioids, cannabis, cocaine and alcohol

Abstract Background Ascertaining agreement between DSM-IV and DSM-5 is important to determine the applicability of treatments for DSM-IV conditions to persons diagnosed according to the proposed DSM-5. Methods Data from a nationally representative sample of US adults were used to compare concordance of past-year DSM-IV opioid, cannabis, cocaine and alcohol dependence with past-year DSM-5 disorders at thresholds of 3+, 4+, 5+ and 6+ positive DSM-5 criteria among past-year users of opioids (n = 264), cannabis (n = 1622), cocaine (n = 271) and alcohol (n = 23,013). Substance-specific 2 × 2 tables yielded overall concordance (kappa), sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV). Results For DSM-IV alcohol, cocaine and opioid dependence, optimal concordance occurred when 4+ DSM-5 criteria were endorsed, corresponding to the threshold for moderate DSM-5 alcohol, cocaine and opioid use disorders. Maximal concordance of DSM-IV cannabis dependence and DSM-5 cannabis use disorder occurred when 6+ criteria were endorsed, corresponding to the threshold for severe DSM-5 cannabis use disorder. At these optimal thresholds, sensitivity, specificity, PPV and NPV generally exceeded 85% (>75% for cannabis). Conclusions Overall, excellent correspondence of DSM-IV dependence with DSM-5 substance use disorders was documented in this general population sample of alcohol, cannabis, cocaine and opioid users. Applicability of treatments tested for DSM-IV dependence is supported by these results for those with a DSM-5 alcohol, cocaine or opioid use disorder of at least moderate severity or severe cannabis use disorder. Further research is needed to provide evidence for applicability of treatments for persons with milder substance use disorders.
TYPE+CODE II: A Code-Driven Typography

Abstract TYPE+CODE II explores the aesthetic of an experimental code-driven typography created with the Processing programming language. It crosses boundaries between calligraphy, graphic art, typography and computer art. TYPE+CODE II reinterprets typography by combining aspects of traditional hand-drawn calligraphy with contemporary elements based on mathematical expressions and algorithms.
Emotional self-disclosure and emotional avoidance: Relations with symptoms of depression and anxiety.

Research suggests that individuals with heightened symptoms of mood and anxiety disorders engage in diminished emotional disclosure. On the basis of emotion regulation theories, the authors hypothesized that this symptom-disclosure relationship would be mediated by the avoidance of emotional experience and expression. In Study 1, college students (N = 831) completed measures of depression and anxiety symptoms, measures of tendencies to avoid emotional expression, and measures of tendencies to self-disclose distress. Structural equation modeling revealed that anhedonic depression and anxious arousal were associated with lessened emotional self-disclosure tendencies as mediated by avoidance of emotional expression. In Study 2, participants (N = 153) completed new measures of depression and anxiety symptoms, reflected on the most significant emotional event experienced during the past week, and rated their avoidance of emotion about the event and their self-disclosure of the event. Depression (but not anxiety) symptoms were negatively related to the disclosure of a specific event, but avoidance of emotional experience did not mediate this depression-disclosure relationship. These findings extend emotion dysregulation theory and suggest that depressive symptoms in particular are associated with reduced emotional disclosure.
0316 Estimating Personal Exposure to Traffic-Related Air Pollutants among On-Road Workers0316 Estimating Personal Exposure to Traffic-Related Air Pollutants among On-Road Workers

Objectives Many individuals in the U.S. work in close proximity to traffic-related air pollution. Often these jobs require physical activity which increases breathing rate and results in higher personal exposures to pollutants. The goal of this study was to systematically estimate and characterise personal exposure to traffic-related pollutants for those working on or near roadways. Method Concentrations of elemental carbon, carbon monoxide, and PM2.5 were measured along six traffic routes in the City of Chicago. These routes represent varying levels of exposure to traffic-related pollutants. Measurements were taken during peak and off-peak traffic hours during the summer and fall. All measurements were obtained from environmental monitoring equipment affixed to the back of a bicycle. Results Air pollutant levels varied significantly across routes and time of day. Mean carbon monoxide levels ranged from 0.006–1.653 ppm across the sampling events. The geometric mean elemental carbon level was 1.75 µg/m 3 and ranged from 0.23 to 8.38 µg/m 3 . The geometric mean PM 2.5 level was 39 µg/m 3 and ranged from 16 to 270 µg/m 3 . Levels of elemental carbon and PM 2.5 were significantly higher during peak traffic samples than off-peak traffic samples. Conclusions This study uses novel methods to estimate exposure to those who are physically active along roadways including mobile. While there is considerable time and route variation in air pollutant measurement, the levels of air pollutants measured in this study may have serious health implications for those who perform physically demanding activities near or on roadways in the City of Chicago.
The Painful Scrotum: Torsion vs Epididymo-Orchitis

In summary, an acute disorder of the scrotum in a child without previous urologic history must be viewed as torsion until proved otherwise by surgical exploration. No deleterious effects have been reported from such an approach, which requires a minimal period of hospitalization and little discomfort to the child. The shorter the interval between the onset of symptoms and surgical exploration, the greater the likelihood that the testicle will be viable later. The diagnosis of epididymo-orchitis in a healthy child without a history of urologic abnormality or evidence of lower urinary tract infection has no place in the differential diagnosis of the child with the painful scrotum.
Simple approach to the hierarchy problem

We show that gauge-singlet real scalars added to the Standard Model can both soften the little hierarchy problem and offer a candidate for Dark Matter. Masses of the scalars are in the 1–3 TeV range, depending on the Higgs boson mass and the number of singlets present. If the scalars couple to the Majorana mass term for right-handed neutrinos then one neutrino must be massless. The mixing angles are consistent with the tri-bimaximal mixing.
Optimum Bias Calculation for Parallel Hybrid Switching-Linear Regulators

This paper presents an analysis of the bias constraints for switching and linear voltage regulators operated in a parallel-hybrid configuration. Particular emphasis is given to polar and envelope-tracking RF power amplifier (PA) applications requiring wideband dynamic voltage regulation. Ideal expressions are derived for the optimum current contribution of the switching regulator under quasi-static operating conditions. In contrast to previous work, it is shown that the optimum mean current contribution of the switching regulator is not necessarily the DC current to the load, but is a function of the DC and dynamic characteristics of the regulated output voltage. Theoretical maximum efficiency is derived for envelope waveforms that result from two-tone and sinusoidal amplitude modulation of the RF carrier.
Graduated Licensing Laws and Fatal Crashes of Teenage Drivers: A National Study

Objectives: The objective of the current study was to quantify the effects of the strength of US state graduated driver licensing laws and specific licensing components on the rate of teenage driver fatal crash involvements per 100,000 teenagers during 1996–2007. The strengths of state laws were rated good, fair, marginal, or poor based on a system developed previously by the Insurance Institute for Highway Safety. Methods: Analysis was based on quarterly counts of drivers involved in fatal crashes. Associations of overall ratings and individual licensing components with teenage crash rates were evaluated using Poisson regression, with the corresponding fatal crash rate for drivers ages 30–59 controlling for state- or time-dependent influences on crash rates unrelated to graduated licensing laws. Results: Compared with licensing laws rated poor, laws rated good were associated with 30 percent lower fatal crash rates among 15- to 17-year-olds. Laws rated fair yielded fatal crash rates 11 percent lower. The...
DIF Identification Using HGLM for Polytomous Items

The relationship between the hierarchical generalized linear model (HGLM) and item response theory (IRT) models has been demonstrated for dichotomous items. The current study demonstrated the use of the HGLM for polytomous items (termed PHGLM) for identification of differential item functioning (DIF). First, the algebraic equivalence between parameterizations of a constrained form of Muraki's rating scale model and PHGLM was demonstrated. Next, as a precursor to using the PHGLM for DIF identification, a simulation was conducted to compare estimation of item and person latent trait parameters using HLM 5 and PARSCALE software. The resulting PHGLM and IRT parameter estimates were comparable. Last, a simulation was conducted that compared the performance of PHGLM with that of the generalized Mantel-Haenszel statistic for DIF identification. Both approaches performed similarly. Benefits and limitations of using PHGLM for DIF identification are presented. Index terms: hierarchical linear modeling, item respons...
A new quantitative measurement for surgical needle ductility

Because surgical needle ductility is such an important factor in the selection of surgical needles, a new curved needle ductility test instrument was devised to measure the ductility of needles from three commercial manufacturers. The superior ductility of needles made by one manufacturer was related to the specific alloy, stainless steel ASTM 45500, used in their production. The ASTM 45500 stainless steel has a significantly greater tensile and yield strength than the other stainless steel alloys, accounting for its superior ductility.
Serine 254 Enhances an Induced Fit Mechanism in Murine 5-Aminolevulinate Synthase

5-Aminolevulinate synthase (EC 2.3.1.37) (ALAS), a pyridoxal 5′-phosphate (PLP)-dependent enzyme, catalyzes the initial step of heme biosynthesis in animals, fungi, and some bacteria. Condensation of glycine and succinyl coenzyme A produces 5-aminolevulinate, coenzyme A, and carbon dioxide. X-ray crystal structures of Rhodobacter capsulatus ALAS reveal that a conserved active site serine moves to within hydrogen bonding distance of the phenolic oxygen of the PLP cofactor in the closed substrate-bound enzyme conformation and within 3–4 Å of the thioester sulfur atom of bound succinyl-CoA. To evaluate the role(s) of this residue in enzymatic activity, the equivalent serine in murine erythroid ALAS was substituted with alanine or threonine. Although both the KmSCoA and kcat values of the S254A variant increased, by 25- and 2-fold, respectively, the S254T substitution decreased kcat without altering KmSCoA. Furthermore, in relation to wild-type ALAS, the catalytic efficiency of S254A toward glycine improved ∼3-fold, whereas that of S254T diminished ∼3-fold. Circular dichroism spectroscopy revealed that removal of the side chain hydroxyl group in the S254A variant altered the microenvironment of the PLP cofactor and hindered succinyl-CoA binding. Transient kinetic analyses of the variant-catalyzed reactions and protein fluorescence quenching upon 5-aminolevulinate binding demonstrated that the protein conformational transition step associated with product release was predominantly affected. We propose the following: 1) Ser-254 is critical for formation of a competent catalytic complex by coupling succinyl-CoA binding to enzyme conformational equilibria, and 2) the role of the active site serine should be extended to the entire α-oxoamine synthase family of PLP-dependent enzymes.
Clinical utility of insulin-like growth factor binding protein-3 in the evaluation and treatment of short children with suspected growth hormone deficiency.

We have shown previously that serum insulin-like growth factor binding protein-3 (IGFBP-3) levels have good predictive value for complete, but not partial, growth hormone deficiency (GHD). In this study, we compare IGFBP-3 levels in short children previously divided into groups on the basis of their post-stimulation GH levels. Complete GHD (N = 59) included those children with peak post-stimulation GH 5 micrograms/l but 10 micrograms/l. Partial GHD and normal children with short stature also were divided into either low IGF-I or normal IGF-I subgroups. The clinical sensitivity of IGFBP-3 for complete GHD was 92%, whereas its sensitivity for partial GHD was 39%. For partial GHD, among those with low IGF-I (N = 19) 68% were also low for IGFBP-3, while 80% of those with normal IGF-I (N = 30) were also normal for IGFBP-3. The clinical specificity of IGFBP-3 for normal children with short stature was 69%. For these groups, among those with low IGF-I (N = 22) 73% also were low for IGFBP-3, while 80% of those with normal IGF-I (N = 81) also were normal for IGFBP-3. In addition, we tested whether IGFBP-3 can predict the response to GH treatment in prepubertal children by comparing pretreatment IGFBP-3 with the height gain achieved by 1 year of GH treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
Relationship of functional recovery to scar contraction after myocardial infarction in the canine left ventricle

We have previously reported that regional wall motion abnormalities in a canine model of acute myocardial infarction may show substantial improvement in the first 6 weeks after infarction. To determine whether the mechanism of this improvement in function is the result of scar contraction within the infarct, we studied the relationship between changes in regional wall motion defined by cross-sectional echocardiography and the regional concentration of radioactive microspheres injected immediately before coronary occlusion and sampled 6 weeks after occlusion. Eight dogs underwent serial echocardiographic and microsphere blood flow measurements immediately before and 30 minutes, 48 hours, 1 week, 3 weeks, and 6 weeks after ligation of the left anterior descending or the left circumflex coronary artery. Wall motion and blood flow were measured in the short-axis section of the left ventricle at the level of the midpapillary muscle in each 10-degree radial segment around the circumference of the ventricle. Infarct histology was assessed at 6 weeks by means of the same radial coordinate system. Control data were collected in a similar manner from four dogs that underwent sham operations and had no histologic evidence of infarction. In all of the animals with infarcts, but not in the sham animals, the calculated preocclusion endocardial and epicardial blood flow values in the histologic infarct zone (252 ± 44 and 168 ± 17 ml/min/100 gm, respectively, mean ± SEM) were significantly higher than those in the normal opposite wall (endocardial: 106 ± 3 ml/min/100 gm, p < 0.01); epicardial: 108 ± 3 ml/min/100 gm, p < 0.01. The location and circumferential extent of myocardium showing this elevation of preocclusion blood flow correlated well (r = 0.93, p < 0.001) with the location and circumferential extent of the histologic infarct. The amount of wall motion abnormality, measured from the “correlation plot area,” decreased significantly from its maximum value of 39 ± 3 degrees at 48 hours after coronary occlusion to 3 ± 1 degrees (p < 0.001) at 6 weeks after occlusion. The ratio of the preocclusion transmural blood flow in the infarct zone to that in the noninfarct zone, a measure of the condensation of the microspheres injected before coronary occlusion, and therefore of the degree of scar contraction at 6 weeks, correlated well (r = 0.83, p < 0.01) with the recovery of wall motion 6 weeks after infarction. These findings indicate that spontaneous recovery of regional wall motion in the chronic canine infarct is related to the degree of microsphere condensation and therefore to the process of scar contration.
Dorsal cochlear nucleus single neurons can enhance temporal processing capabilities in background noise.

Envelope temporal fluctuations are critical for effective processing of biologically relevant sounds including speech, animal vocalizations, sound-source location and pitch. Amplitude modulation (AM) of sound envelopes can be encoded in quiet with high fidelity by some auditory neurons, including those of the cochlear nucleus. From both neurophysiological and clinical perspectives, it is important to understand the effects of background noise on the processing of AM. To further this goal, single-unit recordings were made from dorsal cochlear nucleus (DCN) units in urethane-anesthetized chinchillas. All units of this study were classified as pauser/buildup or On-s units according to PSTH response patterns, first spike latencies, and shape of best-frequency (BF) rate-intensity functions. BF puretone and AM (10–500 Hz) tone bursts were presented at several sound levels, in quiet and in the presence of a continuous wideband masker. The following was found: (1) DCN units can enhance their AM coding relative to quiet in the presence of loud noise (+14 or +19 dB S/N) and at high signal levels (e.g. 75 dB SPL); (2) for the sample of units of the present study, this is usually achieved by lowering the average firing rate and increasing the synchronous (fundamental frequency) response; (3) for some units, the AM coding stays the same or declines in the background noise. The nature of these findings suggests that part of a DCN unit's abilities to preserve or enhance AM coding with masking noise results from peripheral operating range shifts, whereas part comes from intrinsic circuitry (inhibitory inputs) or cellular mechanisms (dendritic filtering of sound temporal features) within the DCN.
Cancer pain management by radiotherapists: a survey of radiation therapy oncology group physicians

Abstract Purpose: Radiation Therapy Oncology Group (RTOG) physicians were surveyed to determine their approach to and attitudes toward cancer pain management. Methods and Materials: Physicians completed a questionnaire assessing their estimates of the magnitude of pain as a specific problem for cancer patients, their perceptions of the adequacy of pain management, and their report of how they manage pain in their own practice setting. Results: Eighty-three percent believed the majority of cancer patients with pain were undermedicated. Forty percent reported that pain relief in their own practice setting was poor or fair. Assessing a case scenario, 23% would wait until the patient’s prognosis was 6 months or less before starting maximal analgesia. Adjuvants and prophylactic side effect management were underutilized in the treatment plan. Barriers to pain management included poor pain assessment (77%), patient reluctance to report pain (60%), patient reluctance to take analgesics (72%), and staff reluctance to prescribe opioids (41%). Conclusions: Physicians’ perceptions of barriers to cancer pain management remain quite stable over time, and physicians continue to report inadequate pain treatment education. Future educational efforts should target radiation oncologists as an important resource for the treatment of cancer pain.
Scapular kinematics and shoulder elevation in a traditional push-up.

Context: Proper scapulothoracic motion is critical for the health and function of the shoulder and represents a principal focus in the rehabilitation setting. Variants of the traditional push-up are used frequently to help restore proper scapular kinematics. To date, substantial research has focused on muscle activation levels of rotator cuff and scapular-stabilizing musculature, whereas a dearth of literature exists regarding scapular kinematics during push-up variants. Objective: To examine the effect of shoulder position on scapular kinematics across the range of motion (ROM) of a traditional push-up. Design: Cross-sectional study. Setting: University laboratory. Patients or Other Participants: Sixteen healthy participants without a history of upper extremity or spine injury requiring rehabilitation or surgery. Intervention(s): Participants performed a traditional push-up while kinematic measurements were acquired from multiple upper extremity segments. The 3 shoulder position conditions were (1) self-...
Redox properties of the [2Fe-2S] center in the 24 kDa (NQO2) subunit of NADH:ubiquinone oxidoreductase (complex I).

The redox properties of the [2Fe-2S] cluster in the 24 kDa subunit of bovine heart mitochondrial NADH:ubiquinone oxidoreductase (complex I) and three of its homologues have been defined using protein−film voltammetry. The clusters in all four examples display characteristic, pH-dependent redox transitions, which, unusually, can be masked by high ionic strength conditions. At low ionic strength (10 mM NaCl) the reduction potential varies by approximately 100 mV between high and low pH limits (pH 5 and 9); thus the redox process is not strongly coupled and is unlikely to form part of the mechanism of energy transduction in complex I. The pH dependence was shown to result from pH-linked changes in protein charge, due to nonspecific protonation events, rather than from the coupling of a specific ionizable residue, and the ionic strength dependence at high and low pH was modeled using extended Debye−Huckel theory. The low potential of the 24 kDa subunit [2Fe-2S] cluster, out of line with the potentials of the ...
Abstract 4293: Notch expression expands the pre-malignant pool of T-cell acute lymphoblastic leukemia clones without affecting self-renewal

Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL Over 60% of human T-cell acute lymphoblastic leukemias (T-ALL) harbor NOTCH1 activating mutations, and the cMYC pathway is also commonly activated in this disease. Notch and cMyc have been shown to collaborate in mouse transgenic models of T-ALL, suggesting that these oncogenes function in parallel pathways to enhance tumor growth; however, the exact role of each in T-ALL is unknown. Here, we show that co-expression of Notch and cMyc in zebrafish T cells significantly enhances T-ALL progression compared to cMyc or Notch alone (p<0.001). However, Notch co-expression with cMyc does not enhance proliferation, alter cell cycle kinetics, or modify apoptosis in leukemic cells when compared to T-ALLs expressing cMyc alone. Clonality assays using RT-PCR analyses for T-cell receptor-beta rearrangements indicate that Notch increases the number of T-ALL clones contained within the primary tumor when compared to cMyc expressing leukemais. A large portion of T-ALL clones present in primary Notch and Notch/cMyc leukemias cannot transfer disease into transplanted animals, while all cMyc-alone expressing T-ALLs clones are capable of engraftment and reinitiation of leukemia. Large scale limiting dilution cell transplantation analyses using syngeneic zebrafish demonstrated that primary T-ALLs expressing either Notch or Notch/cMyc have 10-fold less leukemia-initiating frequency when compared to T-ALLs that express only cMyc; however, following serial passaging, both the Notch and Notch/cMyc leukemias exhibit similar leukemia-initiating frequency as cMyc-induced T-ALLs, indicating that Notch signaling does not enhance self-renewal of T-ALL initiating cells. Taken together, our data supports a model where Notch expands a pool of pre-malignant T-ALL clones within the primary tumor, a subset of which acquire additional mutations to confer a fully transformed phenotype. By contrast, cMyc alone is insufficient to increase the overall pool of pre-malignant clones but confers a fully-transformed phenotype to leukemic cells, accounting for the longer latency that likely reflects the acquisition of additional genetic changes in clones. Our data may explain why a subset of relapsed human T-ALLs develop from an underrepresented clone found in the primary leukemia, in that primary human T-ALLs likely have a large pool of pre-malignant clones resulting from NOTCH-pathway activation that are unable to self-renew and thus, cannot give rise to relapsed T-ALL. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4293. doi:10.1158/1538-7445.AM2011-4293
Composition- and morphology-dependent corrosion stability of ruthenium oxide materials.

Ruthenium oxide materials were evaluated as possible non-carbon-based supports for fuel cell catalysts. The effects of composition and morphology of ruthenium oxide materials on the conductivity and corrosion stability in the gas-diffusion electrode (GDE) configuration were thoroughly investigated. The compositions of the bulk and surface of three ruthenium oxide materials, along with the surface area and surface morphology, were compared. We have found that all tested ruthenium oxide powders exhibited higher corrosion stability compared to carbon. Full conversion of RuO2·nH2O to the RuO2 phase by postreduction in a hydrogen atmosphere leads to improved conductivity and corrosion stability.
Language Sampling Protocols for Eliciting Text-Level Discourse.

The identification of linguistic vulnerability in school-age students is likely to require collecting and analyzing samples of text-level discourse. Text-level discourse produced as part of narrati...