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There is a global trend to increase the light yield of CsI scintillators used in neutrino and dark matter detection by operating undoped crystals at cryogenic temperatures. However, high light yield alone is not sufficient to guarantee a low-energy threshold. The response of undoped crystals to nuclear recoils at cryogenic temperatures is equally important. A liquid nitrogen-based cryostat was developed to measure the nuclear quenching factor of a small undoped CsI crystal using monoenergetic neutron beams at the Triangle Universities Nuclear Laboratory (TUNL). To minimize neutron scattering, high-Z materials were reduced around the crystal. The structure and performance of the cryostat are described in detail. Using this cryostat, a system light yield of 33. 4 ± 2. 0 photoelectrons per keV electron-equivalent (PE/keV ee) was observed at 5.9 keV ee , enabling the measurement of nuclear quenching factors at very low energies. The results of the quenching factor measurement will be reported in a subsequent paper. Non-negligible negative overshoot was observed in the tails of the observed light pulses. The origin of this issue and the correction procedure are described in detail. This information may be useful for others who encounter similar technical challenges. [ABSTRACT FROM AUTHOR]

Studies photoluminescence and Raman spectra of silicon nanocrystals prepared by Si ion implantation into SiO2 layers on Si substrate at room temperature. Dependence on annealing temperature; Characterized Raman scattering peak of silicon nanocrystals.

The Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) is responsible for the construction and performance testing of the 30 pairs of the international thermonuclear experimental reactor high-temperature superconducting (HTS) current leads. The first pair of poloidal field (PF) coil type, 52-kA HTS current lead prototypes was built and cold tested in ASIPP in mid-2016. The test results demonstrated their excellent performance on low joint resistance, long loss of flow accident time, and high current-sharing temperature. The overheating time, mass flow, and heat loads to 5-K ends also meet the requirements. This paper summarizes the major test results for the PF 52-kA HTS current lead prototypes. [ABSTRACT FROM AUTHOR]

Fatigue damage is a type of damage usually occurring to repeatedly loaded elements of structures in various engineering fields. Accumulation of fatigue damage may cause failure of structural elements. Identification of incipient fatigue damage is essential to ensure safety of structures. Fatigue crack under repeated loads commonly behaves in a nonlinear dynamic manner, typically manifested by both occurrence of higher harmonic components and interaction of harmonic components. Interrogation of nonlinear dynamic manner provides a promising way to characterize structural fatigue damage. This study aims at developing a new method to interrogate nonlinear dynamic manner for fatigue damage identification. This method is based on bispectral analysis of structural vibrational responses. This method portrays fatigue damage by inspecting the presence of higher harmonic components and quantifying the interaction of these harmonic components. The method can precisely locate and quantify a small-sized fatigue damage in a cantilever beam, presenting great accuracy in fatigue damage identification. [ABSTRACT FROM AUTHOR]

Summary: This study aimed to investigate the effect of lactic acid bacteria (LAB) and smectite on the growth performance, nutrient digestibility and blood parameters of broilers that were fed diets contaminated with aflatoxin B1 (AFB1). A total of 480 newly hatched male Arbor Acres broilers were randomly allocated into four groups with six replicates of 20 chicks each. The broilers were fed diets with the AFB1 (40 μg/kg) challenge or without (control) it and supplemented with smectite (3.0 g/kg) or LAB (4.0 × 1010 CFU/kg) based on the AFB1 diet. The trial lasted for 42 days. The results showed that during days 1–42 of AFB1 challenge, the feed intake (FI) and body weight gain (BWG) were depressed (p < .05). The inclusion of LAB and smectite increased (p < .05) the BWG by 71.58 and 41.89 g/bird, respectively, which reached the level of the control diet (p ≥ .05), but there were no differences (p ≥ .05) in performance between LAB and smectite. LAB and smectite also increased (p < .05) the apparent total tract digestibility of the crude protein. Regarding the blood parameters, AFB1 decreased (p < .05) the levels of red blood cell count, haematocrit, mean corpuscular volume, haemoglobin, albumin and total protein. In the meantime, the AFB1 increased (p < .05) leucocyte counts, urea nitrogen, cholesterol, total bilirubin, creatinine, glutamic‐pyruvic transaminase, glutamic oxaloacetic transaminase and alkaline phosphatase. By contrast, LAB and smectite affected (p < .05) these parameters in the opposite direction. It can be concluded that after the AFB1 challenge, LAB and smectite have similar effects on the growth and health of the broilers, suggesting that LAB could be an alternative against AFB1 in commercial animal feeds. [ABSTRACT FROM AUTHOR]

Zn-polar BeMgZnO/ZnO heterostructures grown by molecular beam epitaxy on high resistivity GaN templates producing high-density two-dimensional electron gas (2DEG) are investigated. This is motivated by the need to reach plasmon-longitudinal optical (LO) phonon resonance for attaining minimum LO phonon lifetime. Achievement of high 2DEG concentration in MgZnO/ZnO heterostructures requires growth of the MgZnO barrier at relatively low temperatures, which compromises the ternary quality that in turn hinders potential field effect transistor performance. When this ternary is alloyed further with BeO, the sign of strain in the BeMgZnO barrier on ZnO switches from compressive to tensile, making the piezoelectric and spontaneous polarizations to be additive in the BeMgZnO/ZnO heterostructures much like the Ga-polar AlGaN/GaN heterostructures. As a result, a 2DEG concentration of 1.2 x 1013cm-2 is achieved in the Be0.03Mg0.41Zn0.56O/ZnO heterostructure. For comparison, a 2DEG concentration of 7.7 x 1012cm-2 requires 2% Be and 26% Mg in the barrier, whereas the same in the MgZnO/ZnO system would require incorporation of more than 40% Mg into the barrier, which necessitates very low growth temperatures. Our results are consistent with the demands on achieving short LO phonon lifetimes through plasmon-LO phonon resonance for high carrier velocity. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) and the glutathione (GSH) pathway are protective against aflatoxin, but information on the effect of LAB on aflatoxin metabolism and GSH activity in farm animals is scarce. This study aimed to investigate the effects of LAB and aflatoxin B1 (AFB1) on growth performance, aflatoxin metabolism, and GSH pathway activity using 480 male Arbor Acres broiler chickens from d 1 to 35 of age. Diets were arranged in a 2 × 2 factorial design, including AFB1 at 0 or 40 μg/kg of feed and LAB at 0 or 3 × 1010 cfu/kg of feed, and the LAB was a mixture of equal amounts of Lactobacillus acidophilus, Lactobacillus plantarum, and Enterococcus faecium. The results showed that there were highly significant (P < 0.01) effects of AFB1 toxicity, LAB protection, and their interaction on ADFI, ADG, and G:F of broilers during d 1 to 35. Compared with the AFB1 diet, the LAB diet reduced (P < 0.05) the residues of AFB1 in the liver, kidney, serum, ileal digesta, and excreta on d 14 by 121.5, 80.6, 43.7, 47.0, and 26.5%, respectively, and on d 35 by 40.6, 60.2, 131.7, 37.9, and 32.9%, respectively, whereas the LAB diet increased (P < 0.05) the contents of aflatoxin M1, a metabolite of AFB1, in the liver, kidney, serum, and ileal digesta on d 14 by 98.2, 154.2, 168.6, 19.1, and 34.1%, respectively, and in the kidney and serum on d 35 by 32.6 and 142.2%, respectively. For the activity of the GSH pathway in the liver and duodenal mucosa, there were significant (P ≤ 0.01) effects of LAB and AFB1 on reduced GSH, glutathione S-transferases (GST), and glutathione reductase (GR) on d 14 and 35; compared with the control diet, the LAB diet increased (P < 0.05) GSH, GST, and GR by a range of 11.6 to 86.1%, and compared with the AFB1 diet, the LAB diet increased (P < 0.05) GSH, GST, and GR by a range of 24.1 to 146.9%. In the liver, there were interactions (P < 0.05) on GSH and GST on d 14 and on GSH on d 35; in the mucosa, interactions were significant (P ≤ 0.01) on GSH and GR on d 14 and on GST on d 35. It can be concluded that LAB is effective in the detoxification of AFB1 by modulating toxin metabolism and activating the GSH pathway in animals. [ABSTRACT FROM AUTHOR]

Supercritical fluids have shown an increasing interest as reactive media (tunable properties from liquid to gas) to synthesize nanostructured materials by thermal decomposition of inorganic precursors at relatively low pressure and temperature. The particle formation process (nucleation and growth) is made by high supersaturation in the supercritical fluid. So, the adjustment of synthesis process parameters results in a precise control of particle shape, size (between 10 nm and 10 µm), and chemical composition. We present the technique of thermal, chemical-heat, and structural strength treatment of materials to produce nanostructured nickel oxinitride in supercritical ammonia (solvent and reactant) from the thermal decomposition of nickel hexafluroroacetylacetonate (280°C, 18 MPa). A preliminary study concerning magnetic properties of the material was done and a correlation between particle size and magnetic behavior was pointed out. [ABSTRACT FROM AUTHOR]

Modulation bandwidth and energy efficiency of metallic cavity nanolasers are studied in both small signal and digital modulation formats. Special emphasis is placed on the effects of noise on data rate and energy efficiency. It is found that the data rate for nanolasers of small sizes is severely limited by noise-induced bit-error rate. The trade-off between size-reduction and noise effects leads to an optimal cavity size to achieve the highest data rate. The energy data-rate ratio decreases in general with device size, but starts to increase in ultrasmall devices, due to increased threshold current and noise effects. However, relatively high modulation rate and energy efficiency can be achieved in metallic cavity nanolasers. Calculations show that a low energy consumption of 30 fJ/bit at a high data rate of 120 Gbit/s can be realized in nanolasers as small as V = 16 ( λ/ nr)3 ( V is the laser cavity volume). Ultralow energy consumption per bit (<10 fJ/bit) does require smaller devices ( V<2.1 ( λ/ nr)3), while the noise limits the data rate to below 50 Gbit/s. Such a balanced and holistic consideration between device size, data rate, noise effects, and energy efficiency offers new perspectives to nanolaser design strategy for future onchip integrated nanophotonics systems. [ABSTRACT FROM AUTHOR]

This paper reports on a comparative study of the impact of phosphorous and boron doped microcrystalline silicon oxide (μc-SiO x:H) layers on the surface passivation of n- and p-type doped crystalline silicon float zone wafers in correlation with the material properties of the μc-SiO x:H layers. The poor surface passivation of μc-SiO x:H films deposited directly on c-Si surface might be attributed to the incorporation of doping impurities, the surface damaging by ion bombardment and (or) the low amount of hydrogen at the μc-SiO x:H/c-Si interface. The different impact of n- and p-type doped μc-SiO x:H films on the passivation of n- and p-type doped wafers with and without an additional a-SiO x:H passivation layer are correlated to the differences in the strength of the field effect at the heterojunction and to the presence of boron atoms that can cause the rupture of Si-H bonds. [ABSTRACT FROM AUTHOR]

A thermodynamic problem between pyrrole and water was calculated to investigate the possibility of this reaction. Based on the thermodynamic analysis, simulation experiments on the pyrrole-water system were carried out at 400–500°C. Properties of the reaction products were characterized by gas-chromatography and Fourier transform-infrared spectrometry methods. Apparent reaction kinetics between pyrrole and water were tentatively discussed. The results show that thermochemically the organic-inorganic interaction between pyrrole and water possibly occurs above 100°C, and proceeds spontaneously above 300°C to produce furan and ammonia as the main products. The calculated apparent activation energy for the reaction is 146.91 kJ/mol. [ABSTRACT FROM AUTHOR]

We have investigated the variations of optical property and electronic structure in heavily Al-doped ZnO (AZO) films during the growth process, which were formed by first creating Zn vacancies in O2-rich atmosphere and second filling the vacancies with Zn atoms in Zn-vapor atmosphere. After the first step, the high-resistance AZO films have the same optical bandgap with nominally undoped ZnO, indicating that negligible variations in the fundamental bandgap happened to the AZO films although Al atom was incorporated into the ZnO lattice. After the second step, once free electrons were brought into the lattice by Zn-filling, the optical transition energy blueshifts due to the band-filling effect. X-ray absorption fine structure measurements suggest that Zn-filling process decreased the unoccupied states of the conduction band, but not raised the conduction band minimum. [ABSTRACT FROM AUTHOR]

The recently emerged metallic-cavity nanolasers have opened a new phase of miniaturization of semiconductor lasers down to sub-wavelength scale. This new type of semiconductor lasers is suitable for many low-power applications due to its small size, tight optical confinement and good heat dissipation. However, there are major technical challenges in the fabrication of such nanolasers that must be overcome to make high-quality devices with high yield needed for practical applications. Here we will discuss several fabrication issues that are critical to the device performance. These issues, including device patterning, pillar etching, surface passivation and metal deposition, will determine both optical and electrical properties, especially the lifetime, threshold, and efficiency of a nanolaser. [ABSTRACT FROM AUTHOR]

The effect of aluminum doping on the growth of ZnO films on c-plane ZnO (0001) single crystal substrates during metalorganic chemical vapor deposition was investigated. It was found that aluminum doping induces a growth mode of three-dimensional columnar growth. X-ray photoemission spectroscopy demonstrates that partial aluminum is segregated to the growth front. A combined experimental contact angle measurements and theoretical first-principle calculations suggest that the surface energy of the films is promoted by aluminum doping. Besides, aluminum doping also tends to decrease the adatoms diffusion mobility. We conclude that aluminum acts as an antisurfactant element during the homoepitaxial growth, and it increases the difficulty in obtaining high quality n-type ZnO films. [ABSTRACT FROM AUTHOR]

The co-crystal of 9-fluorenone and naphthalene-1, 5-diamine has been prepared and its structure is characterized by single-crystal X-ray analysis. It belongs to monoclinic system, space group P2/ c with a = 9.0421(7), b = 18.1114(14), c = 8.1444(6) Å; β = 104.7232(10)°; V = 1296.20(17) Å, Z = 4. The crystal packing is stabilized by N-H...O intermolecular hydrogen bonds, as well as π-π stacking. Optical studies showed that the co-crystal exhibited red shift in PMMA film. The hydrogen bonds were easily destroyed in solvent. [ABSTRACT FROM AUTHOR]

A moving train subjects a rail cross section to many wheel passes and heat generation at the interface from bulk friction and microslip. Frictional heating at the interface causes the temperature of the contacting rail surface and wheel surface to rise. After the train has passed, the rail temperature drops to ambient till the next train arrives. Wheels, on the other hand, pick up the frictional heat input continuously and hence their steady state temperature could be much higher than that of the rail. A hot wheel provides an additional temperature rise at the rail surface. The accompanying thermal stresses and thermal softening may enhance the rail wear rate. This has been investigated in the present study. A ratchetting failure-based computer simulation has been employed to assess the wear rate of a pearlitic rail steel. It is found that the thermal stress effect on wear rate is only the modest, but thermal softening can enhance the wear rate by up to an order of magnitude for the conditions considered. [ABSTRACT FROM AUTHOR]

Abstract: Wear rate in a rail–wheel system has been found to be a function of temperature rise between the rail and wheel. The flash temperature due to frictional heating causes the development of thermal stresses and reduction of the material strength at the rail undergoing wear. This thermal effect leads to a rapid increase in wear rate, known as wear transition. Rail wear transition behaviour as a result of frictional heating in the contact region has been investigated using a computer modelling technique and the results are presented here. The model is based on ratchetting failure, which is caused by the accumulation of plastic strain in the rail material over many cycles. Plastic strain causes the rail material to harden but as the temperature increases, thermal softening may occur, which can reduce the strength of the material. Above a certain temperature, both thermal stress and thermal softening can significantly influence the wear rate. The variations in the slip/roll ratio, the peak pressure, the friction coefficient, and the vehicle speed on the wear rate show that the transition from mild to severe wear occurs at temperatures above 350°C. During this transition the vehicle speed has the least effect on the temperature and wear rate among the other parameters. [Copyright &y& Elsevier]

Plasmonic nanolasers and spasers continue to attract a great deal of interest from the physics and nanophotonics community, with the experimental observation of lasing as a focus of research. We report the observation of continuous wave lasing in metallic cavities of deep subwavelength sizes under electrical injection, operating at room temperature. The volume of the nanolaser is as small as 0.42&lembda;3, where &lembda; = 1.55 µum is the lasing wavelength. This demonstration will help answer the question of how small a nanolaser can be made, and will likely stimulate a wide range of fundamental studies in basic laser physics and quantum optics on truly subwavelength scales. In addition, such nanolasers may lead to many potential applications, such as on-chip integrated photonic systems for communication, computing, and detection. [ABSTRACT FROM AUTHOR]

Zizyphi Spinosi Semen is well known as a kind of herb for the treatment of insomnia and anxiety. However, due to the lack of purified compounds for functional tests, limited data proves pharmacological activities of each jujubasaponin monomer. In this study, we developed a novel method for the preparative separation and purification of jujuboside A, A1, B, and B1, simultaneously, from Zizyphi Spinosi Semen. Macroporous resin and reversed-phase flash chromatography was successfully used and gave a good resolution of each jujubasaponins monomer. Jujuboside A, A1, B, and B1 with a purity of over 98% were yielded. [ABSTRACT FROM AUTHOR]

In the presence of water, thermal simulation experiments on the reaction between CH4 and MgSO4 were conducted at high temperatures and high pressures. Chemical and carbon isotopic variations were characterized with advanced analytical methods, including microcoulometry, gas chromatography, Fourier transform infrared spectroscopy, X-ray diffraction, and gas chromatograph combustion isotope ratio mass spectrometry. It was found that CH4 can react with MgSO4 to produce H2S, CO2, and MgO as the main products of thermochemical sulfate reduction. The carbon kinetic isotope fractionation was tentatively investigated using quantum chemistry and the kinetic isotope effect was calculated. [ABSTRACT FROM AUTHOR]

Thermal simulation experiments on the reaction between n-C8H18 and CaSO4 were carried out under high temperatures and high pressures. Properties of the reaction products are characterized by advanced analytical methods. Based on the results of simulation experiments, possible reaction pathways and thermodynamic characteristics were tentatively investigated. It was found that n-C8H18 can react with CaSO4 to produce CaCO3, H2S, CO2, H2O, CS2, and a series of organic sulfur compounds (OSCs). The conversion of elemental sulfur in the molecular structure of CaSO4 to small molecule inorganic sulfides and thiophene sulfur increases with the increase of temperature. There is a strong thermodynamic drive for the reaction of n-C8H18 with CaSO4 and high temperature is favorable to the reaction. This study may provide new insights into the origin of OSCs in petroleum. [ABSTRACT FROM AUTHOR]

Presenilin mutations are linked to the early onset familial Alzheimer's disease (FAD) and lead to a range of neuronal changes, indicating that presenilins interact with multiple cellular pathways to regulate neuronal functions. In this report, we demonstrate the effects of FAD-linked presenilin 1 mutation (PS1M146L) on the expression and distribution of filamin, an actin cross-linking protein that interacts with PS1 both physically and genetically. By using immunohistochemical methods, we evaluated hippocampal dentate gyrus for alterations of proteins involved in synaptic plasticity. Among many proteins expressed in the hippocampus, calretinin, glutamic acid decarboxylase (GAD67), parvalbumin, and filamin displayed distinct changes in their expression and/or distribution patterns. Striking anti-filamin immunoreactivity was associated with the polymorphic cells of hilar region only in transgenic mice expressing PS1M146L. In over 20% of the PS1M146L mice, the hippocampus of the left hemisphere displayed more pronounced upregulation of filamin than that of the right hemisphere. Anti-filamin labeled the hilar neurons only after the PS1M146L mice reached after four months of age. Double labeling immunohistochemical analyses showed that anti-filamin labeled neurons partially overlapped with cholecystokinin (CCK), somatostatin, GAD67, parvalbumin, and calretinin immunoreactive neurons. In cultured HEK293 cells, PS1 overexpression resulted in filamin redistribution from near cell peripheries to cytoplasm. Treatment of CHO cells stably expressing PS1 with WPE-III-31C or DAPT, selective γ-secretase inhibitors, did not suppress the effects of PS1 overexpression on filamin. These studies support a γ-secretase-independent role of PS1 in modulation of filamin-mediated actin cytoskeleton. [ABSTRACT FROM AUTHOR]

Background: Hypertension (HTN), a recognized adverse effect of angiogenesis inhibitors, may be a potential biomarker of activity of these agents. We conducted a retrospective analysis to examine the incidence and predictors of the development of on-treatment HTN with the vascular endothelial growth factor receptor tyrosine kinase inhibitor cediranib, and the relationship of this adverse event with treatment outcomes.Patients and methods: BR24 was a double-blind placebo-controlled phase II trial of carboplatin/paclitaxel chemotherapy with either daily oral cediranib or placebo in patients (n = 296) with advanced non-small-cell lung cancer (NSCLC). Exploratory analyses characterized relationships between HTN, baseline variables, and efficacy outcomes.Results: New onset or worsening of preexisting HTN (treatment-emergent HTN) was more frequent in patients receiving cediranib (68 versus 45%, P < 0.0001). Factors associated with HTN in all randomized patients were good performance status and treatment with cediranib. In both arms, treatment-emergent HTN was associated with improved efficacy outcomes, but there was no evidence of a differential treatment effect, with nonsignificant interaction P values.Conclusions: In advanced NSCLC, HTN is frequent in patients receiving chemotherapy, with or without cediranib. The development of HTN was favorably prognostic in these patients, but not predictive of a differential outcome with cediranib. [ABSTRACT FROM PUBLISHER]

Isothermal simulation experiments on natural gas-CaSO4-H2O system and natural gas-MgSO4-H2O system were conducted at 450-570°C. Properties of reaction products were analyzed by microcoulometry, gas-chromatography, Fourier transform-infrared spectrometry, and X-ray diffraction methods. Based on the experiments, composition of products, geochemical characteristics, and thermodynamics of natural gas-CaSO4-H2O system were compared with those of natural gas-MgSO4-H2O system. It was found that H2S, CO2, and carbon were the common products of the two thermochemical sulfate reduction systems. In thermochemical sulfate reduction process, CaSO4 was reduced to CaCO3 while MgSO4 was reduced to MgO. At the same reaction temperature, the effect of thermochemical sulfate reduction on natural gas was more intensified in natural gas-MgSO4-H2O system than natural gas-CaSO4-H2O system. With the same temperature and hydrocarbon, MgSO4 more easily participates thermodynamically in the reactions than CaSO4. [ABSTRACT FROM AUTHOR]

A 68 kA trial-high temperature superconducting current lead for the ITER magnet coil had been developed and tested in parallel with a 52 kA HTS trial lead at ASIPP in Dec. 2008. In order to verify the safety and reliability of HTS section of HTS trial lead, three sub size samples cooled with a GM cooler have been fabricated and tested. Based on the successful sub size HTS module's test results, a novel binary shunt comprising bronze and stainless steel cylinders is applied to HTS trial lead to reduce the conductional heat load to the 5 K cryogenic system and increase the burnout time after quench. This paper gives the numerical calculation of loss of flow accident (LOFA) of HTS trial lead and HTS temperature margin analysis. The measured results of the LOFA and burnout time for the 68 kA trial-HTS current lead are briefly discussed in the paper. The test results indicate the LOFA time is more than 300 s and the burnout time of 21 s is reached more than the requirement of the toroidal field coil fast discharge time of 13 s. [ABSTRACT FROM AUTHOR]

The magnetotransport properties of a nominally undoped InGaN thin film grown by metal-organic chemical vapor deposition were investigated. Resistivity was measured under a magnetic field up to 5 T over the temperature range of 3 to 298 K. The film exhibits a negative magnetoresistance at low temperatures. Its magnitude decreases with increasing temperature, and turns to be positive for temperatures above 100 K. The negative component was described by a model proposed by Khosla and Fischer for spin scattering of carriers in an impurity band. The positive part was attributed to the effect of Lorentz force on the carrier motion. Agreement between the model and the data is presented. [ABSTRACT FROM AUTHOR]

Thermal simulation experiments on thermochemical sulfate reduction system of natural gas and magnesium sulphate were carried out using an autoclave in the presence of water. The products were characterized by some advanced analytical methods. Thermodynamics and reaction kinetics of thermochemical sulfate reduction processes had been investigated on the basis of the experimental data. The results showed that thermochemical sulfate reduction of natural gas with magnesium sulphate could proceed at 425°C-525°C to produce magnesium oxide, carbon, hydrogen sulfide, and carbon dioxide as the main products. The reactions are thermochemically possible and high temperature is favored. Long-chain hydrocarbons more easily thermodynamically participate in the reactions than short-chain hydrocarbons. According to the reaction model, the calculated activation energy for the reaction between natural gas and magnesium sulfate is about 78.975 kJ/mol. [ABSTRACT FROM AUTHOR]

The electroluminescence efficiency at room temperature and low temperature (15 K) in a wide-narrow-well InGaN/GaN light-emitting diode with a narrow last well (1.5 nm) and a narrow next-to-last barrier (5 nm) is investigated to study the efficiency droop phenomenon. A reduced droop in the wide wells and a reduced droop at low temperatures reveals that inferior hole transportation ability induced Auger recombination is the root for the droop at high excitation levels. [ABSTRACT FROM AUTHOR]

In order to study the effect of flotation reagents on the properties of coal-water slurry, a sub-bituminous coal was cleaned via either forward flotation or reverse flotation. The froth product from the forward flotation, obtained with the use of diesel oil and MIBC, and the tailings of the reverse flotation, carried out with dextrin-tannic acid depressants and dodecyltrimethylammonium chloride collector, were used in the preparation of coal-water slurries. It was shown that while it was possible to obtain the coal-water slurry with a high-solids content from the coal rendered hydrophilic (tailings from the coal reverse flotation), in the case of the hydrophobic product (froth product from the forward flotation) a dispersing agent was required to obtain the coal-water slurry of the same high-solids content. [ABSTRACT FROM AUTHOR]

This retrospective case study assessed the influence of item non-response error on subsequent response to questionnaire items assessing adolescent alcohol and marijuana use. Post-hoc analyses were conducted on survey results obtained from 4,371 7th to 12th grade students in Ohio in 2005. A skip pattern design in a conventional questionnaire appeared to increase nonresponse error rates at first introduction. In previous cigarette users, these errors were associated with under-reporting of alcohol and marijuana use on subsequent questions. These effects were less prevalent in high-achieving students. Skip patterns can contribute to substantial underestimation of alcohol and marijuana use in adolescents. [ABSTRACT FROM AUTHOR]

Abstract: The target of novel signal transduction inhibitors may be present on normal as well as tumor cells, resulting in mechanistic adverse effects (AE) in addition to antitumor activity. As those AEs lie in the causal pathway that patients respond to the drug, may thus serve as an indicator of benefit from the drug. In this paper, we discuss issues in validating drug related AEs as predictive markers of overall survival benefit. Based on our proposed approach, we showed that erlotinib induced skin rash appears to predict a survival benefit. [Copyright &y& Elsevier]

This paper presents our new development of parallel finite element algorithms for elastic–plastic problems. The proposed method is based on dividing the original structure under consideration into a number of substructures which are treated as isolated finite element models via the interface conditions. Throughout the analysis, each processor stores only the information relevant to its substructure and generates the local stiffness matrix. A parallel substructure oriented preconditioned conjugate gradient method, which is combined with MR smoothing and diagonal storage scheme are employed to solve linear systems of equations. After having obtained the displacements of the problem under consideration, a substepping scheme is used to integrate elastic–plastic stress–strain relations. The procedure outlined controls the error of the computed stress by choosing each substep size automatically according to a prescribed tolerance. The combination of these algorithms shows a good speedup when increasing the number of processors and the effective solution of 3D elastic–plastic problems whose size is much too large for a single workstation becomes possible. [ABSTRACT FROM AUTHOR]

We carried out univariate and bivariate linkage analyses to identify genomic regions that may influence plasma levels of C-reactive protein (CRP) and fibrinogen and exert pleiotropic effects on both traits. Subjects included African American (AA, n=1310, mean age 62.7±9.4 years) and non-Hispanic white (NHW, n=796, mean age 58.4±9.8 years) belonging to hypertensive sibships. Plasma CRP was measured by an immunoturbidimetric assay and fibrinogen by the Clauss method. Genotyping was performed at 366 microsatellite marker loci spaced ∼10 cM apart across the 22 autosomes. Estimation of heritability and linkage analyses was carried out using a variance components approach. Significant heritability was noted for CRP (0.38 in AA and 0.37 in NHW subjects) and fibrinogen (0.44 in AA and 0.28 in NHW subjects). Significant genetic correlation between CRP and fibrinogen was present in both AA (0.39) and NHW (0.40) subjects. In univariate linkage analysis, the maximum logarithm of odds (LOD) score for CRP was on chromosome 10q22 in NHW (LOD=1.69, 106.75 cM, P=0.0026) and for fibrinogen on chromosome 2 in AA (LOD=2.14, 55.5 cM, P=0.0009) subjects. Bivariate linkage analysis demonstrated suggestive evidence of linkage (defined as LOD score2.87) for both traits on chromosome 12 (LOD=3.44, 152.16 cM, P=0.0003) in AA and on chromosome 21 (LOD=3.03, 13.05 cM, P=0.0008) in NHW subjects. Plasma CRP and fibrinogen levels are heritable and genetically correlated. Linkage analyses identified several chromosomal regions that may harbour genes influencing CRP and fibrinogen levels and exert pleiotropic effects on both traits.Journal of Human Hypertension (2008) 22, 102–110; doi:10.1038/sj.jhh.1002297; published online 25 October 2007 [ABSTRACT FROM AUTHOR]

Butt joints containing glued cover plates and bolts are used in structures subjected to severe loading with a view to maximising the structural integrity. The behaviour of such joints is not well understood due to the complex interaction of a large number of components as well as material nonlinearities. This paper presents an analysis of bonded-bolted steel butt joints with particular attention to the effect of the loss of bolt tightness to the structural behaviour. Bonded-bolted butt joints subjected to biaxial stress field have been investigated using three-dimensional finite element modelling subjected to two-step loading, the first involving pre-stressing of the bolts followed by application of inplane bending. Effect of looseness of the bolts to the inplane deformation characteristics of the joint has been particularly examined. [Copyright &y& Elsevier]

An attractive process of coal reverse flotation could become a viable option only if the huge consumption of quaternary amine collector could be significantly reduced. In the present search for the ways of reducing the collector dosage in this process the authors turned out their attention to polymers used as blinders in potash flotation. The batch flotation tests carried out using mechanical cells confirmed that some polyacrylamides worked very well as blinders in the coal reverse flotation process. At the same time, the standard flocculation tests were showing that the polyacrylamides acted as total non-selective flocculants. This obvious discrepancy revealed the importance of conditioning in the selective flocculation. The reverse flotation with a simultaneous use of the polyacrylamide, which significantly reduced consumption of amine collector, can be selective only after sufficient conditioning. It was found that the polyacrylamides with a different degree of anionicity responded differently to conditioning. Only the addition of the polymers with a lower degree of anionicity promoted the gangue flotation. The quality of the clean coal improved with conditioning by breaking up the totally flocculated larger flocs into selectively flocculated material that could then be floated with quaternary amine. [ABSTRACT FROM AUTHOR]

Summary: Background: Cisplatin-induced anemia may correlate with adverse events, poor quality of life (QoL), decreased adjuvant chemotherapy (ACT) dose intensity, shorter relapse-free survival (RFS) or overall survival (OS). Methods: The JBR.10 trial demonstrated significantly longer survival with adjuvant cisplatin and vinorelbine (n =242) compared to observation (n =240) in patients with resected NSCLC [Winton T, Livingston R, Johnson D, Rigas J, Johnston M, Butts C, et al. Vinorelbine plus cisplatin vs. observation in resected non-small-cell lung cancer. N Engl J Med 2005;352(25):2640–2]. This exploratory analysis evaluates the predictive value of baseline (in all patients) and during-treatment (in ACT arm only) hemoglobin (Hb) levels on OS and RFS when adjusted for prognostic factors. Baseline (in all patients) and during treatment (in ACT arm only) Hb levels were also correlated with adverse events, QoL, morbidity and ACT dose intensity. Results: Baseline Hb did not predict RFS or OS. However, there was a trend to shorter OS (p =0.1) when baseline Hb was <120g/L. Lower baseline Hb predicted increased hospitalization (p =0.04) and worse QoL (SOB item, p =0.03) but had no impact on adverse events or dose intensity. There was a trend to longer RFS (p =0.08) in patients with lower nadir during-treatment Hb and to longer OS (p =0.06) and RFS (p =0.08) in patients with maximum during-treatment Hb drop >30% that was not maintained when ACT dose intensity was included in the model. Maximum during-treatment Hb drop >30% correlated with increased lethargy (p =0.003) and worse QoL (fatigue item, p =0.07). Conclusions: Lower baseline and during-treatment Hb levels seem associated with poorer QoL, fatigue and increased hospitalization. There is a trend for shorter OS in patients with lower baseline Hb levels. [Copyright &y& Elsevier]

OBJECTIVE: To examine the prevalence and trend of inhalant use among Indiana public school students. METHODS: The Alcohol, Tobacco, and Other Drug Use among Indiana Children and Adolescents surveys conducted annually between 1991 and 2004 were reanalyzed using 2-way moving average, Poisson regression, and ANOVA tests. RESULTS: The prevalence had increased during 1991- 1997, decreased during 1997- 2002, and increased again since 2003. Poisson model estimated an average annual decrease rate of 5.6%. The intensity of inhalant use had also decreased. More males and Hispanics use inhalants. CONCLUSION: Inhalant use needs to be addressed in drug prevention programs. [ABSTRACT FROM AUTHOR]

Laser shock peening (LSP) is an innovative surface treatment technique successfully applied to improving fatigue performance of metallic materials. The fatigue strength and fatigue life of the laser peened material can be significantly improved by deep compressive residual stresses being introduced into the material. The compressive residual stress distribution along the depth of the material is attributed to a high amplitude stress wave induced by a high energy laser pulse. The present paper describes a finite element method for simulating the residual stress distribution in a metal alloy 35CD4 50 HRC steel in single and multiple LSP processes. The process used a three-dimensional dynamic finite element model impacted by a square laser spot. The predicted results for single LSP were well correlated with the available experimental data. Meanwhile, the effects of multiple LSP processes, pressure magnitude and duration, and laser spot sizes on the compressive stress field in the metal alloy were evaluated for the purpose of optimising the process. [ABSTRACT FROM AUTHOR]

Laser shock peening (LSP) is a fatigue enhancement surface treatment for metallic materials. The key beneficial characteristic of LSP is the presence of compressive residual stresses mechanically produced by shock waves within the metallic materials, which can significantly improve their fatigue life and fatigue strength. During LSP, a laser beam can be directed to impact on either one side or two sides of a target. Generally, when treating a thin section, two sided peening is used to avoid harmful effects such as spalling and fracture, which may occur when only one side of a thin section is laser peened. The present work focuses on applying the finite element method to predict the distribution of residual stresses along the surface and depth of thin sections of a Ti-6Al-4V alloy in single and multiple LSP. In order to understand the effects of the target geometry on the distribution of residual stresses, the residual stress profiles corresponding to various target thicknesses were carefully evaluated. Residual stresses and dynamic stresses were also presented and correlated with experimental data from the literature. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To examine the feasibility of using a composite index of smoking behaviors to analyze adolescent smoking. METHODS: A secondary analysis of data from 10 annual surveys (1991-2000), from 566,467 Indiana students in grades 6 through 12. A composite index was calculated, and differences between index scores were analyzed using 1-way ANOVA, Tukey's post hoc tests, and 2-way moving averages. RESULTS: Index scores increased before 1997 and decreased after 1976, with greater change among 7th through 10th graders. CONCLUSIONS: The 2-way moving average comparison of a composite index, used with prevalence-based trend analyses, provides a more complete picture of changes in adolescent cigarette smoking. [ABSTRACT FROM AUTHOR]

The use of the Monte Carlo method to generate particle positions is important in both forward- and inverse-scattering problems of microwave and optical waves in dense media. The generated realizations of a random heterogeneous medium can be used for the numerical solutions of Maxwell's equations. In this paper, we perform Monte Carlo simulations of densely packed sticky particles that have diversity in both size and surface adhesion. The simulation algorithm allows a particle to break or form bonds with other particles during the Monte Carlo displacement. Monte Carlo simulation results are, demonstrated to be in good agreement with Percus–Yevick pair distribution functions. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 187–192, 2001. [ABSTRACT FROM AUTHOR]

Presents information on a study which focused on a homogenization scheme used in examining the influence of a ductile interphase on the nonlinear behavior of the fiber-reinforced system. Constitutive equations of the ductile phases; Effective elastic moduli of the linear comparison composite; Anisotropic stress-strain relations of the fiber-reinforced composite.

Presents a study which developed a homogenization theory to determine the elastoplastic behavior of a particle-reinforced composite with a ductile interphase. Information on the homogenization theory; Details on the method used to develop the theory; Examination of the accuracy of the theory; Applicability of the theory.

In their Comment, Y. Zhou and M. W. Wu claim that the fundamental transport equation relating the current to the transmission function, used by us and in fact by numerous other researchers, is invalid for extended systems and should be corrected. They provide a "correct" new formula for transport in extended systems. This would be indeed a surprising new aspect of quantum transport theory. Here we show mathematically, however, that the "new formula" is a misconception resulting from adding an energy- and momentum-dependent function that has to vanish, due to fundamental reasons. Results and conclusions stemming from adding this function are irrelevant. The known established formulas for quantum transport are consistent with each other under the well-documented conditions. [ABSTRACT FROM AUTHOR]