cssi/SciSciGPT-SciSciNet huggingface dataset:
Transport deficient (TR-) hyperbilirubinemic rats are resistant to acetaminophen hepatotoxicity.

Abstract The biliary excretion of acetaminophen (APAP) is reduced in transport deficient (TR − ) hyperbilirubinemic rats lacking the multidrug resistance-associated protein 2 (Mrp2). This mutant strain of Wistar rats has impaired biliary excretion of organic anions and increased hepatic glutathione. The rational for this study was to determine if there is an altered risk for liver damage by APAP in the absence of Mrp2. Therefore, the susceptibility of TR − rats to APAP hepatotoxicity was investigated. Male Wistar and TR − rats were fasted overnight before APAP treatment (1 g/kg). Hepatotoxicity was assessed 24 h later by plasma sorbitol dehydrogenase activity and histopathology. In other studies, TR − rats received buthionine sulfoximine before APAP to reduce hepatic glutathione to values similar to those in Wistar rats. mRNA expression of APAP metabolizing enzymes was also measured in naive animals. Wistar rats treated with APAP showed significant elevations in plasma sorbitol dehydrogenase activity, while no increases in enzyme activity were observed in TR − rats. Histopathology was in agreement. Hepatic non-protein sulfhydryls were significantly lower in Wistar rats receiving APAP than in TR − rats. TR − rats treated with buthionine sulfoximine and APAP showed dramatic increases in hepatotoxicity. TR − rats had increased mRNA expression of several APAP metabolizing enzymes. Mrp2 expression not only is important in biliary excretion, but also influences the toxic potential of reactive intermediates by controlling intrahepatic GSH and possibly drug metabolism.
Molecular modeling and synthesis of polymers for use in applications requiring a low-k dielectric

Abstract As integrated circuits have become more and more complex and with smaller and smaller feature sizes several limitations have become apparent. One of these is the need for low-k dielectric materials as insulating layers. Recent work has reported promising materials for such insulators that include some fluorinated polymers. These dielectric materials were further improved by introducing porosity into the polymer films. One of the key factors in the dielectric constant of a material is its density. As the polarization of the material is related to the number of bonds, the dielectric constant will scale with the density. In this paper a series of molecular modeling calculations were conducted on various fluorine substituted polymers in order to predict their densities. A surprising result of these calculations was the prediction that some of the polymers would have densities less than 1 g/cm 3 . One of these polymers was synthesized and the density determined. The calculated density was in extremely good agreement with the experimental density. This paper will present the details of the molecular modeling technique as well as the synthesis and characterization of one of the polymers of interest.
Gallium arsenide and indium arsenide surfaces produced by metalorganic vapor-phase epitaxy

Abstract Thin films of GaAs and InAs were deposited on GaAs(0 0 1) substrates by metalorganic vapor-phase epitaxy (MOVPE), and their surfaces were characterized by scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and low-energy electron diffraction (LEED). Gallium arsenide surfaces produced in the MOVPE reactor at 570°C and a V/III ratio of 50 exhibit a (1×2) reconstruction, and are covered with weakly bound alkyl groups. Heating this material in flowing hydrogen in the reactor produces a variety of surface phases, depending on the sample temperature. These phases include (2×4) and (4×2) reconstructions, all of which are terminated with As or Ga dimers. The surfaces of InAs films grown by MOVPE exhibit these same phases. This study demonstrates that compound semiconductor surfaces formed in the MOVPE environment are nearly the same as those produced by molecular-beam epitaxy under ultrahigh vacuum conditions.
Quality in Training Organizations

This article examines the implications of applying quality principles to the systematic design of training, considering 1) the definition and characteristics of a quality training system, 2) the requirements for establishing such a system, 3) how TQM might impact present procedures and, 4) some anticipated reactions of experienced designers to the idea of a quality training system.
Photophysical properties of coplanar and twisted 1,4-bis(9-ethynylanthracenyl)benzene. Rotational equilibration in the excited states of diaryalkynes

We report the synthesis and photophysical properties of 1,4-bis(9-ethynylanthracenyl)benzene. Results in dilute hexane solutions give a very high fluorescence quantum yield (Φ = 0.97) and a lifetime of τ = 1.8 ns. Studies at different temperatures, viscosities, and micromorphologies, as well as excited-state semiempirical calculations, indicate that conformations having aryl groups coplanar absorb and emit at wavelengths that are longer than those that have their aryl groups orthogonal or twisted. A simple MO picture is consistent with essentially frictionless aryl group rotation in the ground state and a relatively high rotational barrier in cummulene-like excited states.
Selected psychosocial characteristics of black unwed adolescent fathers

Adolescent fathers and nonfathers were compared as to their belief in a sense of personal control and responsibility for their own lives (locus of control); ability to optimistically trust others (interpersonal trust); taking an active orientation to life's demands and problems (coping style); and family/generational pattern of unwed parenthood. Participants were 24 unwed adolescent fathers and 27 unwed adolescent nonfathers, aged 15–19 years. Each participant completed a questionnaire containing a Rotter Internal-External Locus of Control Scale, the Rotter Interpersonal Trust Scale, the Behavioral Attributes of Psychosocial Competence, and a scale measuring family pattern of unwed parenthood. Results suggest that adolescent fathers are usually older, more likely to have been born out-of-wedlock, and less trusting than nonfathers. The implications for casework with adolescent fathers are discussed.
Electrical power systems fault location with one-terminal data using estimated remote source impedance

In this study, a fault location algorithm for electrical power systems is presented. The proposal consists in an accurate impedance-based fault location algorithm by utilizing voltage and current measurements from local terminal and estimated remote source impedance. In order to evaluate the fault location algorithm a numerical analysis is made. Phase-to-ground faults are simulated in a 230 kV Brazilian transmission line using the software ATP/EMTP and MATLAB. The algorithm is tested considering the fault distance, fault resistance, and the variation of short-circuit capacity of remote system effects. The results show that the fault resistance and fault distance affect the estimated fault distance, but with minor errors. More, the proposed algorithm is not sensitive to the remote system short-circuit capacity variation.
Quantitation of Fibrosis of the Heart in Chronic Obstructive Pulmonary Disease with and without Cor Pulmonale

This study examined the hearts of 55 patients dying of chronic obstructive pulmonary disease, with and without cor pulmonale, quantitated histologically the degree of myocardial fibrosis in the left and right ventricle, and determined the relationship to associated disease states. Comparison has been made to a control group of 17 patients free of cardiopulmonary disease. Patients with associated and advanced ischemic heart disease, as proved by marked atherosclerosis and myocardial infarction, have significantly increased myocardial fibrosis throughout all layers of the left ventricular wall in comparison to control patients or patients with chronic obstructive pulmonary disease free of associated cardiac disease. Right ventricular fibrosis was not significantly increased; however, one case showed a marked degree of fibrosis related to myocardial infarction. Subdivision of patients with chronic obstructive pulmonary disease into groups with definite anatomic right ventricular hypertrophy, a clinical diagnosis of cor pulmonale, or with chronic hypoxemia failed to show any difference in the percentage of myocardial fibrosis of the ventricles among these groups. Increased fibrosis of the right or left ventricle in patients with chronic obstructive pulmonary disease, therefore, is not related to the degree of myocardial hypertrophy pathologically, the hypoxemic state, or clinical heart failure, but to ischemic heart disease with myocardial infarction.
Evolution of Multi Agent Systems Under a New Communication Topology

In this paper, a multi agent system (MAS) is considered as particles of a continuum deforming under a specific class of homeomorphic mappings, called a homogenous transformation. We have recently showed how a desired homogenous mapping of the MAS in a n–D space can be prescribed by transient positions of n + 1 leaders placed at the vertices of a n–D polytope, called leading polytope [1–9]. In this article, we first minimize the acceleration norm with (i) initial and final positions of the leaders known and (ii) leaders (located at the vertices of the leading polytope) are constrained to move in such a way that the initial volume of the leading polytope is preserved during evolution. The followers learn the leader-determined homogenous map through local communication with each follower modeled as a double integrator. Proposed is a communication topology that requires every follower agent to update its position based on communication with n + 1 local agents. The weights of communication are uniquely specified by the initial positions of the agents. Simulation of a MAS moving in a plane validates the proposed communication topology.Copyright © 2014 by ASME
Al Qaeda and al Qaeda in the Arabian Peninsula: Inspired, Homegrown Terrorism in the United States

This article analyzes a facet of the phenomenon of al Qaeda (AQ) and al Qaeda in the Arabian Peninsula (AQAP)-inspired terrorism on U.S. soil. The twenty case studies addressed in this piece are illustrative of the nature of the current threat as well as foreshadows future risks of transnational jihad.
A coordination chemistry model of algal autoflocculation

Abstract Autoflocculation is triggered by the coordination of cationic surface sites on mineral precipitates, or Ca + 2 and Mg + 2 , to anionic algal carboxylate groups. The solution composition controls on autoflocculation can be quantitatively described using surface complexation models of algal, Mg(OH) 2 , hydroxylapatite, and calcite interfaces. Cation bridging of adjacent algae triggers autoflocculation at lower pH than does Mg(OH) 2 formation. Autoflocculation in response to lime addition reaches a maximum at pH ~ 11 because of Mg(OH) 2 formation, but then plateaus with further lime addition because of the decrease in Mg(OH) 2 surface charge with increasing pH. Hydroxylapatite surfaces are positively charged, hence able to autoflocculate algae, under most conditions. Calcite surfaces are positively charged, and autoflocculation potential is high, when dissolved Ca + 2 and Mg + 2 levels are high; calcite has low autoflocculation potential when Ca + 2 and Mg + 2 levels are low and sulfate levels are high, and the calcite surface is negatively charged.
A measure of vigilance in infancy

Abstract These studies were designed to investigate visual vigilance, that is, attention to the location of an anticipated event, in infants. The general paradigm was to present the infants with interesting puppet events, with intervals between events ranging from 5 to 25 seconds. The dependent measure was the amount of time the infant spent looking between events at the place of the events' occurrence. In the first study with infants of 5, 7, 9, and 11 months, there were no age differences in the duration of looking either at the events themselves or at the place of the puppet's appearance and disappearance during the intervals between events. Compared to the inter-event looking of younger infants, however, the looking of the 9- and 11-month-olds was composed less of looks that were continuations of looks at the puppet before it disappeared and more of looks at that place later in the inter-event intervals. In two other studies of 10-month-olds, the amount of looking at the place of occurrence during inter-event intervals was influenced by the salience of those events, suggesting the effects of motivation. In all studies, the variation among individuals was high; in addition, the correlations between the first half of the session and the second half were strong and positive. The results suggest that elements of vigilance are present at an early age, and that there are consistent individual differences in the extent to which such attention is maintained.
Formation of an amorphous Rh‐Si alloy by interfacial reaction between amorphous Si and crystalline Rh thin films

Interfacial reaction in bilayers of amorphous Si and crystalline Rh thin films has been studied by transmission electron diffraction and microscopy. In a bilayer of ∼190‐A amorphous Si and ∼60‐A polycrystalline Rh films, we have observed the formation of an amorphous Rh‐Si alloy film upon thermal annealing at 300 °C. The amorphous alloy film crystallizes into the RhSi phase at 400 °C. On the other hand, no amorphous alloy formation was observed upon annealing a bilayer of ∼150‐A amorphous Si and ∼100‐A polycrystalline Rh films; instead, they react at 300 °C to form Rh2Si, followed by the formation of RhSi or a mixture of RhSi and Rh5Si3 around 400 °C.
Reach-scale manipulations show invertebrate grazers depress algal resources in streams

Experimental tools that enable manipulations of organisms at larger scales allow for comparisons of processes across multiple spatial scales and expand our ability to make predictions about ecological processes. We performed reach-scale (i.e., 50 m 2 ) manipulations of invertebrate communities in streams using a modified electroshocking technique to non-destructively remove invertebrates. In addition, we conducted a microcosm experiment (i.e., 157 cm 2 ) with different grazer densities that enabled comparison of the strength of grazer-algal interactions at large and small spatial scales. In high-elevation headwater streams, electroshocking reduced total invertebrate abundance by 84% in a 50-m 2 reach of stream. Although mobile invertebrates recolonized the manipulated area rapidly, daily electroshocking maintained the density reduction. Electroshocking reduced the density of herbivorous invertebrates 86%, which resulted in a 57% increase in algal biomass, whereas in a stream that was not electroshocked, invertebrate density and algal biomass changed much less, only 16 and 8%, respectively. Comparison of grazer effect on periphyton between microcosm and reach-scale experiments revealed that the per capita interaction strength of grazers on primary producers was three times greater in the reach-scale manipulation than that observed in the microcosm experiments. Reach-scale manipulation of invertebrate grazers in streams provides a powerful method to experimentally test patterns observed in the field at a large spatial scale, with more realism than streamside microcosms or small cages in streams.
Determination of the orientation of C 60 adsorbed on Au(111) and Ag(111)

Adsorbate bonding and preferred adsorption sites and rotational orientations of ${\mathrm{C}}_{60}$ on Au(111) and Ag(111) were studied using scanning tunneling microscopy (STM) and related techniques. Spatially resolved tunneling spectroscopy and barrier height measurements indicated that bonding occurs by charge transfer from the metal to ${\mathrm{C}}_{60}$. The internal structure of adsorbed ${\mathrm{C}}_{60}$ observed by STM was found to be a strong function of the adsorption site, the molecular orientation, and the tunneling bias. Occupied state images were found to reflect the adsorption site symmetry while unoccupied state images reflected the molecular symmetry. In domains where all the molecules were in equivalent adsorption sites, the observed internal structure of adsorbed ${\mathrm{C}}_{60}$ was assigned to an on-top site with the five-membered ring on the surface.
Quantum yields and energy partitioning in the ultraviolet photodissociation of 1,2 dibromo-tetrafluoroethane (Halon-2402)

The photodissociation of 1,2 dibromo-tetrafluoroethane (Halon-2402) has been investigated at 193 nm using photofragment translational spectroscopy with vacuum ultraviolet ionization and at 193, 233, and 266 nm using state-selected translational spectroscopy with resonance-enhanced multiphoton ionization. The product branching ratios, angular distributions, and translational energy distributions were measured at these wavelengths, providing insight into the ultraviolet photodissociation dynamics of CF2BrCF2Br. The total bromine atom quantum yields were found to be 1.9±0.1 at both 193 and 233 nm and 1.4±0.1 at 266 nm. The first C–Br bond dissociation energy was determined to be 69.3 kcal/mol from ab initio calculations. The second C–Br bond dissociation energy was determined to be 16±2 kcal/mol by modeling of the bromine quantum yield. In addition, variational Rice–Ramsperger–Kassel–Marcus theory was used to calculate the secondary dissociation rates for a range of dissociation energies above threshold. These results suggest that CF2CF2Br photofragments with sufficient internal energies will undergo secondary dissociation prior to collisional stabilization under atmospheric conditions. Based on the measured translational energy distributions and product branching ratios, a model is proposed to describe the wavelength-dependent bromine quantum yield and the implications of these results to atmospheric chemistry are discussed.
TELECOMMUNICATION EXTERNAL ECONOMIES, CITY SIZE AND OPTIMAL PRICING FOR TELECOMMUNICATIONS*

. In this paper I make use of a city systems model to examine how telecommunications may affect cities in urban systems. The model offers an explanation for the observation that the share of employment in the communication-intensive producer-service sector increases with city size in the U.S. I suggest that external scale economies associated with metropolitan employment size, telecommunication network size and total number of intrametropolitan telecommunication contacts are possible explanations for this observation. I go on to suggest that the presence of telecommunication size and contact level external scale economies at the metropolitan level affects the optimal price that should be charged for local telecommunication services.
Straight subjectivities in homonormative spaces: moving towards a new, ‘dynamic’ heteronormativity?

Although scholars have explored geographies of heterosexuality for a relatively long time, experiences of heterosexual subjects have been under-researched. Contributing to the discussions around how homo/straight spaces are negotiated, this study analyses how heterosexuals experience and define both homonormative and heteronormative spaces in Seattle. Through a series of interviews and focus groups with self-identified heterosexuals, I explore how these subjects interact with spaces that they recognize as being either straight or gay, and how they negotiate their own identities in relation to those spaces. I also describe how, while refusing to reject heterosexuality, the vast majority of participants expressed discomfort at being defined as someone with a fixed, stable sexual identity, and how they assumed gayness to be non-transgressive and fixed. The results show a paradoxical, complex picture, in which gayness is described as stable and normative, and heterosexuality is depicted as fluid and dynamic. ...
Blood-Gas Changes and Pulmonary Hemodynamics following Acute Myocardial Infarction

Arterial and mixed venous oxygen tensions were measured in 24 patients following acute myocardial infarction while they were breathing air and 100% oxygen. Total venous admixture and the right-to-left shunt during 100% oxygen breathing were calculated. These data were related to the pulmonary arterial diastolic pressure, the cardiac index, and the central blood volume. Patients with myocardial infarction that was not complicated by congestive failure had blood gases, pulmonary shunts, and pulmonary arterial diastolic pressures comparable to control patients who were at rest in bed. When congestive failure complicated myocardial infarction, arterial blood oxygen tension was lower, pulmonary shunting was increased, and the pulmonary arterial diastolic pressure was elevated. Cardiac index and central blood volume were usually normal. The present data quantitate the contribution of anatomic shunting to the hypoxemia observed in myocardial infarction. Hypoxemia and increased anatomic shunting are closely corre...
Evolution of helium stars.

The evolution of helium stars in the mass range from 4 to 15 solar masses has been followed from the initial helium main sequence to the end of carbon burning in the core, with the use of Carson's (1976) radiative opacities. As compared with earlier work based on smaller opacities, the main-sequence band in the H-R diagram is now both wider and cooler than before. If neutrino losses are neglected in the stellar models, the phase of carbon burning in the core occurs in the red-supergiant region; otherwise, it occurs, as it does in the earlier models with or without neutrino emission, close to the helium main sequence. Observational data for Wolf-Rayet stars and R Coronae Borealis variables are found to lend some support to the present models.
The dependence of recombination kinetics on photoexcitation density in a-Si:H

Using pulsed excitation we observe a strong correlation between the recombination kinetics transition (monomolecular-to-bimolecular) and the optical absorption exponential (Urbach) edge. This correlation is observed over a wide range of Si dangling bond defect density in undoped, singly doped and compensated material. The results show that deep gap-states do not determine the excitation density at which the transition occurs. An important implication of these results is that deep gap-states do not play a major role in early recombination in a-Si:H.
Effect of a polystyrene-polyisoprene diblock layer on the adhesion between polystyrene and polyisoprene

Abstract The adhesion between polystyrene and crosslinked polyisoprene homopolymers was found to be increased by the presence of a thin layer of polystyrene-polyisoprene block copolymer at the interface. The interfacial toughness was a function of both the layer thickness and molecular weight of the copolymer. If the homopolyisoprene was crosslinked before the joint was made, the joint failed at a relatively low toughness by the polyisoprene of the diblock pulling out of the polyisoprene homopolymer. Joints that failed by pull-out could be reformed by contact at room temperature. A high degree of interfacial toughness was found when the homopolymer and copolymer polyisoprene were crosslinked together.
Assessing rural-urban disparities in the use of sentinel lymph node biopsy for melanoma.

Abstract Background We hypothesized that patients in urban areas with intermediate thickness cutaneous melanoma would have higher rates of sentinel lymph node biopsy (SLNB) relative to their rural-dwelling counterparts. Methods The Surveillance, Epidemiology, and End Results database was queried for patients who underwent surgery for intermediate thickness cutaneous melanoma from 2004–2008. Patients were categorized as coming from urban or rural counties based on a nine-point scale. We used multivariate logistic regression models to predict use of SLNB. Covariates examined included sex, race/ethnicity, age, T stage, tumor histology, tumor location, and ulceration. The likelihood of undergoing SLNB was reported as OR with 95% CI. Results Of 8441 patients, 8382 (99.3%) had complete information regarding use of SLNB. On multivariate analysis, patients from rural counties had a decreased likelihood of receiving a SLNB (OR 0.87, CI 0.78–0.97; P = 0.014). Additional factors associated with a decreased likelihood of receiving a SLNB included increasing age, Asian/Hispanic/Unknown race, and head and neck or overlapping primary tumor site. Conclusions Patients in rural areas are less likely to receive a SLNB for intermediate thickness cutaneous melanoma than their urban-dwelling counterparts.
Multispectral scanning during endoscopy guides biopsy of dysplasia in Barrett's esophagus

Esophageal cancer is increasing in frequency in the United States faster than any other cancer. Barrett’s esophagus, an otherwise benign complication of esophageal reflux, affects approximately three million Americans and precedes almost all cases of esophageal cancer. If detected as high-grade dysplasia (HGD), most esophageal cancers can be prevented. Standard-of-care screening for dysplasia uses visual endoscopy and a prescribed pattern of biopsy. This procedure, in which a tiny fraction of the affected tissue is selected for pathological examination, has a low probability of detection because dysplasia is highly focal and visually indistinguishable. We developed a system called endoscopic polarized scanning spectroscopy (EPSS), which performs rapid optical scanning and multispectral imaging of the entire esophageal surface and provides diagnoses in near real time. By detecting and mapping suspicious sites, guided biopsy of invisible, precancerous dysplasia becomes practicable. Here we report the development of EPSS and its application in several clinical cases, one of which merits special consideration.
Image identification and restoration: A survey

Blurred and noisy images can often be represented as nonstationary two-dimensional stochastic processes that can be modelled by a set of linear space-varying state equations or by an ARMA input-output equation. Effects of any distortion resulting from blur and noise might then be removed by Kalman-type filtering and/or by ARMA smoothing respectively, provided that the appropriate image parameter are available. However, because such parameters are a priori unknown for any arbitrary image and furthermore vary spatially as the image is scanned, adaptive identification-filtering procedures appear to be very useful for satisfactory restoration.
EFFECTS OF MEMORY LOAD ON JOKE AND LEXICAL DECISION TASKS

The effects of a five-digit memory load on joke and lexical decision tasks were measured. 72 college students read jokes ending with punchlines, consistent endings, or inconsistent endings and deci...
Comparison of Gestational Age Classifications: Date of Last Menstrual Period vs. Clinical Estimate

Purpose The purpose was to compare the two different measures of gestational age currently used on birth certificates (the duration of pregnancy based on the date of last menstrual period [LMP] and the clinical estimate [CE] as related to health status indicators. We contrasted these measures by race/ethnicity. Methods NCHS natality files for 2000–2002 were used, selecting cases of single live birth to U.S. resident mothers with both LMP and CE gestational age information. Results Approximately 75% of the records had valid LMP and CE values and for approximately one-half of these, the LMP and CE values did not exactly agree. Overall and for each race and ethnic group, the LMP measures resulted in higher proportions of very preterm, preterm, postterm and SGA births. CE value provided preterm rates of 7.9% and for LMP, 9.9%. The odds ratio of preterm birth for African-Americans using the CE measure was 1.78 [95% Cl 1.77–1.79]. The odds ratio using LMP was 1.93 [95% Cl 1.92–1.94]. Whites were the referent population. Conclusions Different measures of gestational age result in different overall and race-specific rates of very preterm, preterm, postterm, and SGA births. These findings indicate that substituting or combining these measures may have consequences.
Superior Mesenteric Artery Syndrome in a Tube-Fed Patient

Obstruction resulting from superior mesenteric artery syndrome is not often considered a possible cause for gastrostomy-tube complications in tube-fed patients. This case report details our experience with a patient who had had a feeding gastrostomy tube in place for 2 years. She then developed continuous leakage around the area of the gastrostomy insertion site associated with pain and inability to tolerate feedings. Her gastrointestinal series revealed compression of the third portion of the duodenum with delayed emptying of the stomach and dilatation of the proximal duodenum. After resection of the necrotic gastrostomy site, takedown of the ligament of Treitz to free the fourth portion of the duodenum, and insertion of a feeding jejunostomy, the patient was again able to gain weight and tolerate her tube feedings. We present this as an unusual complication occurring in a tube-fed patient.
Conventional and living carbocationic polymerizations united. II. The conversion of conventional to living isobutylene polymerization by proton trap and a comprehensive closed‐loop mechanism of proton trap mediated living polymerization

The effect of the proton trap, 2,6hyphen;di-tert-butylpyridine (DtBP), on the polymerization of isobutylene (IB) induced by the “HX”/TiCl4 (“HX” = protoic impurity) intiating system has been studied. Significantly, in the presence of a large (∼ 40 molar) excess of DtBP relative to “HX”, free proton-induced chain transfer-dominated conventional IB polymerization is converted to living polymerization. In the absence of the proton trap the kinetics are dominated by rapid proton-induced processs which overwhelm the relatively slower living polymerization. These investigations also led to a quantitative assessment of the concentration of initiating species: [“HX”] = 1.46 × 10−4 mol/L. The polymerizations are first-order in monomer and the apparent rate constants of propagation drop precipituously with increasing DtBP concentration until a constant low value is reached. The rate of formation of propagating living chains has been expressed quantitatively. Chain transfer is bimolecular and first order in monomer, and kinetic investigations led to a quantitative description of the effect of proton trap concentration on the apparent first order chain transfer constant. The results have been explained in terms of a simple mechanistic scheme. © 1996 John Wiley & Sons, Inc.
Statistical Determination of Surface Flaw Density in Brittle Materials

The density of surface flaws in brittle materials can be determined from the loads in many different kinds of tests. A general method is derived and applied to indentation experiments on crown, plate, window, lead, and commercial heat-resistant and heat-absorbing glasses. Knowledge of flaw density is important for estimating size effect, and differences in flaw density indicate the possibility of significant improvements in strength by eliminating a few major sources of flaws.
Identification of Novel Vesicles in the Cytosol to Vacuole Protein Degradation Pathway

The key gluconeogenic enzyme, fructose1,6-bisphosphatase (FBPase), is induced when Saccharomyces cerevisiae are starved of glucose. FBPase is targeted from the cytosol to the yeast vacuole for degradation when glucose-starved cells are replenished with fresh glucose. Several vid mutants defective in the glucose-induced degradation of FBPase in the vacuole have been isolated. In some vid mutants, FBPase is found in punctate structures in the cytoplasm. When extracts from these cells are fractionated, a substantial amount of FBPase is sedimentable in the high speed pellet, suggesting that FBPase is associated with intracellular structures in these vid mutants. In this paper we investigated whether FBPase association with intracellular structures also existed in wild-type cells. We report the purification of novel FBPase-associated vesicles from wild-type cells to near homogeneity. Kinetic studies indicate that FBPase association with these vesicles is stimulated by glucose and occurs only transiently, suggesting that these vesicles are intermediate in the FBPase degradation pathway. Fractionation analysis demonstrates that these vesicles are distinct from known organelles such as the vacuole, ER, Golgi, mitochondria, peroxisomes, endosomes, COPI, or COPII vesicles. Under EM, these vesicles are 30–40 nm in diam. Proteinase K experiments indicate that the majority of FBPase is sequestered inside the vesicles. We propose that FBPase is imported into these vesicles before entering the vacuole.
MicroRNA-1 transfected embryonic stem cells enhance cardiac myocyte differentiation and inhibit apoptosis by modulating the PTEN/Akt pathway in the infarcted heart.

microRNAs (miRs) have emerged as critical modulators of various physiological processes including stem cell differentiation. Indeed, miR-1 has been reported to play an integral role in the regulati...
System identification using the fast LMS-sine algorithm

The authors extend the desirable features inherent in the gradient LMS (least-mean-square) algorithm and explore an approach aimed at improving its convergence rate. They modify the LMS algorithm by adding a nonlinear term in the update recursion. The resulting algorithm emulates the dynamics of a planar pendulum, and in the steady-state it reduces to an LMS algorithm with much smoother learning curves. Additionally, the new algorithm has a much faster convergence rate than existing gradient algorithms. >
Effect of sensory disuse on geniculate afferents to cat visual cortex

In the kitten, as little as a week of monocular lid suture during early life causes a remarkable remodeling of the geniculocortical projections serving the deprived eye (Antonini & Stryker, 1993a, 1996). While the physiological effects of monocular deprivation have been shown to be due to competitive interactions between the projections serving the two eyes, it is not known whether these morphological changes are due to competitive interactions or to sensory disuse. We addressed this question by analyzing the morphology of geniculocortical arbors in kittens deprived of patterned vision by binocular lid suture for 1 week or 2 weeks ending at 6 weeks of age. Such deprivation would be expected to affect the afferents serving the two eyes equally, giving neither eye a competitive advantage. The arbors were anterogradely filled with Phaseolus lectin iontophoretically injected into lamina A of the lateral geniculate nucleus. The lectin was visualized immunohistochemically, and single geniculocortical arbors were serially reconstructed in three dimensions. Arbors reconstructed in binocularly deprived animals were compared with arbors serving the deprived and nondeprived eye in animals monocularly deprived by lid suture of one eye for a week and with arbors obtained in age-matched normal controls. Geniculocortical arbors in binocularly deprived animals did not suffer the drastic remodeling of the deprived arbors in monocularly deprived animals. Indeed, arbors in binocularly deprived animals were indistinguishable from arbors in normal kittens or nondeprived arbors in short-term monocularly deprived animals. These results support the notion that competitive mechanisms rather than sensory disuse are responsible for gross morphological remodeling of geniculocortical arbors.
Nitric oxide via cGMP-dependent mechanisms increases dye coupling and excitability of rat supraoptic nucleus neurons.

Unlike many neuron populations, supraoptic nucleus (SON) neurons are rich in both nitric oxide synthase (NOS) and the NO receptor-soluble guanylyl cyclase (GC), the activation of which leads to cGMP accumulation. Elevations in cGMP result in increased coupling among SON neurons. We investigated the effect of NO on dye coupling in SONs from male, proestrus virgin female, and lactating rats. In 167 slices 263 SON neurons were recorded; 210 of these neurons were injected intracellularly (one neuron per SON) with Lucifer yellow (LY). The typically minimal coupling seen in virgin females was increased nearly fourfold by the NO precursor, l-arginine, or the NO donor, sodium nitroprusside (SNP).l-Arginine-induced coupling was abolished by a NOS inhibitor. In slices from male and lactating rats who have a higher basal incidence of coupling, SNP increased coupling by approximately twofold over control ( p
Monitoring Early Reading Development in First Grade: Word Identification Fluency versus Nonsense Word Fluency

This study contrasts the validity of 2 early reading curriculum-based measurement (CBM) measures: word identification fluency and nonsense word fluency. At-risk children (n = 151) were assessed (a) on criterion reading measures in the fall and spring of first grade and (b) on the 2 CBM measures each week for 7 weeks and twice weekly for an additional 13 weeks. Concurrent and predictive validity for CBM performance level and predictive validity for CBM slopes demonstrated the superiority of word identification fluency over nonsense word fluency. Findings are discussed in terms of the measures' utility for identifying children in need of intensive instruction and for monitoring children's progress through first grade.
Boredom or Challenge for the Academically Talented in School

This paper examines the hypothesis that gifted children are bored in the conventional classroom. A total of 227 students, identified as academically talented; and 226 not so identified were given a questionnaire which indicated that gifted students often begin with positive attitudes towards school but fail to maintain these attitudes because of the lack of appropriate challenge. However, there was no difference between the groups in level of boredom.
Design and Optimization of a Tiered Wireless Access Network

Although having high potential for broadband wireless access, wireless mesh networks are known to suffer from throughput and fairness problems, and are thus hard to scale to large size. To this end, hierarchical architectures provide a solution to this scalability problem. In this paper, we address the problem of design and optimization of a tiered wireless access network. At the lower tier, mesh routers are clustered based on traffic demands and delay requirements. The cluster heads are equipped with wireless optical transceivers and form the upper tier free space optical (FSO) network. We first present a plane sweeping and clustering algorithm aiming to minimize the number of clusters. PSC sweeps the network area and captures cluster members under delay and traffic load constraints. We then present an algebraic connectivity-based formulation for FSO network topology optimization and develop a greedy edge-appending algorithm that iteratively inserts edges to maximize algebraic connectivity. The proposed algorithms are analyzed and evaluated via simulations, and are shown to be highly effective as compared to the performance bounds derived in this paper.
Graphene nanoribbons exfoliated from graphite surface dislocation bands by electrostatic force

We have developed a novel technique to produce long and narrow graphene ribbons with smooth edges. This technique is free of any chemical treatments and involves a combination of two steps: (i) creation of surface dislocation ribbons by high velocity clusters impacting the graphite surface and (ii) electrostatic transferring of the dislocation ribbons to a desired substrate. The width of the ribbons can be controlled by varying the impact velocity of a cluster jet stream from a gas jet impactor. The electrical transport properties were investigated on the ribbons in field effect transistor (FET) configuration. The p-type behavior observed under ambient conditions was found to be reversed upon annealing at 180 degrees C in a vacuum of 10( - 7) Torr. Charge transfer effects were observed when the degassed graphene was exposed to N(2)O and NH(3).
Software Reliability Models: Assumptions, Limitations, and Applicability

A number of analytical models have been proposed during the past 15 years for assessing the reliability of a software system. In this paper we present an overview of the key modeling approaches, provide a critical analysis of the underlying assumptions, and assess the limitations and applicability of these models during the software development cycle. We also propose a step-by-step procedure for fitting a model and illustrate it via an analysis of failure data from a medium-sized real-time command and control software system.
Mechanisms of endothelial P2Y1- and P2Y2-mediated vasodilatation involve differential [Ca2+]i responses

The present study was designed to evaluate the role of endothelial intracellular Ca2+ concentration ([Ca2+]i) in the difference between P2Y1- and P2Y2-mediated vasodilatations in cerebral arteries....
Estudio de los espacios virtuales como soportes para la violencia de género en la adolescencia

The objective of the study is to demonstrate the virtual spaces as supports for Gender-based violence in adolescence. For this, the USC participates , along with other Spanish Universities Eight , in a team led by the University of Barcelona. This study is funding by the BBVA in which we are collecting data from a sample of 4,500 teenagers enrolled in 3rd and 4th (high school). The instrument used is an electronic questionnaire in Likert-type scale questions. The results will develop guidelines paragraph intervention and awareness of violent behavior among young men and women.
Homogeneity of Media Diet in a Fragmented Media Landscape

The study assesses the nature of selective exposure and avoidance behaviors among political liberals and conservatives using a survey of 351 American citizens obtained through Amazon’s Mechanical Turk. Analyses of a new “homogeneity of media diet” measure indicate that although liberals and conservatives consume a comparable total number of media sources, the homogeneity of those media sources is significantly higher among liberals than it is among conservatives. In fact, whether looking at political ideology or party affiliation, the story is the same: people on the left are significantly more likely than conservatives to selectively attend to ideologically-consonant media sources and are significantly more likely than conservatives to selectively avoid ideologically-divergent media sources. Analyses include an examination of partisan perceptions of the ideological leanings of various media sources as well as the predictive power of self-reported selective exposure. Implications for democratic theory are discussed.
The Impact of Previous Online Course Experience RN Students' Perceptions of Quality.

The purpose of this paper is to explore whether experienced online students (who have completed seven or more online courses) perceive the quality of their courses differently than novice online students (who have completed three or fewer online courses) or students with an intermediate level of online course experience (those who have completed four to six online courses). Overall, 3,160 online students completed a survey which asked them to indicate the extent to which statements derived from the Quality Matters rubric contributed to student success. The results indicate that students rated some items differently based on their previous online course experience. Novice online learners felt that having netiquette guidelines clearly stated was more important than experienced online learners. Experienced learners rated several items as being more important than novice and/or intermediate online learners, including items related to self-introductions, appropriateness of assessments, relevance and quality of instructional materials, clarity of requirements for interaction, ease of navigation, and availability of required technologies. The implications of these findings for course designers and instructors are discussed.
Regulation of α-Globin mRNA Stability

mRNA stability is a critical determinant of normal red blood cell development and function. The long half-life of globin mRNA is central to the continued synthesis of globin proteins throughout all stages of erythropoiesis, even as the cells undergo programmed transcriptional arrest during terminal differentiation. Studies of a naturally occurring alpha-thalassemic mutation that triggers marked destabilization of alpha-globin mRNA first led investigators to search for a stability determinant in the 3'-untranslated region (3'UTR). Analysis of this region identified three cytosine-rich (C-rich) segments that contributed to alpha-globin mRNA stability when studied in transfected erythroid cells. Subsequently, in vitro studies demonstrated assembly of a sequence-specific ribonucleic-protein (RNP) complex at this site. Mutations in the 3'UTR that blocked formation of this "alpha-complex" in vitro resulted in a parallel destabilization of alpha-globin mRNA in transfected cells. Members of the alpha-globin poly(C)-binding protein (alphaCP) subfamily of heteronuclear (hn) RNP K homology (KH) domain RNA-binding proteins have been identified as essential protein components of the alpha-complex. In vitro studies suggested that additional proteins may also contribute to alpha-complex structure and/or function. Surveys of additional highly stable mRNAs point to a general function for the alpha-complex in mRNA stabilization. In vitro and in vivo analyses indicated that the alpha-complex stabilizes alpha-globin mRNA by two mechanisms: control of 3'-terminal deadenylation and steric protection of an endoribonuclease-sensitive site. Confirmation of these pathways, determination of their relative importance, and generalization of these findings to additional systems await future studies.
The Analysis to Failure of Tappet in Engine

The engine appear noise,the face of the tappet which contact with valve stem is concave,through search for root,by chemical analysis,micro-hardness test,metallographic examination,CAE analysis and failure mode validation,it was considered that the failure was caused by the friction wear due to the roughness of the valve stem face.
The level of protective antibodies against measles virus in pregnant women before labor admitted to our hospital

Objective To study the level of protective antibodies against measles virus( MV) in serum isolated from pregnant women before labor in our hospital and to predict it's protection on infants. Method The level of MV antibody Ig G in serum was tested with enzyme-linked immunosorbent assay( ELISA). The SPSS software of version 17. 0 was used to conduct statistical analysis into the test results. Findings 89. 50% of the 419 pregnant women were found to be positive of MV Ig G,to bear a level of serum MV Ig G ranging from 5. 5 to 28208. 5 m Iu / ml,and to have a geometric mean of 1405. 2± 2202. 9 m IU / ml. However,only 44. 39% of the women were found to reach a level higher than1000 m IU / ml which is the minimum level to be able to protect the fetus. A greater percentage of women from the rural areas of Hangzhou were found to reach the protective level of MV Ig G antibodies than those women from city( P 0. 05). Conclusion Low MV Ig G level and low protective rate in pregnant women before labor was identified in the study. We suggest that measles vaccination should be provided to women of childbearing age before pregnancy.
In vivo radiolabeling of platelet proteins: a new method with identification of platelet factor XIII

A method for radiolabeling platelets in vivo was developed in which 3H-arginine was injected into the bone marrow of normal dogs. On the third day after injection, a maximum of 6%--7% of the radioactivity had been incorporated into the total platelet mass. This method of isotope administration resulted in a 50--60-fold increase in maximum uptake of radiolabel by platelets, as compared to values obtained by others using intravenous injections of various radioactive compounds. Tritium-labeled platelets were harvested from the animals and then were washed to remove unbound 3H-arginine. On polyacrylamide gel electrophoresis 7 labeled protein bands, with molecular weights ranging from 29,000to 132,000, were obtained from the platelet-soluble fraction. One 3H-containing protein with a molecular weight of 81,000 was identified immunologically and enzymatically as platelet factor XIII.