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The mechanical properties and thermal conductivity of W-0.5 wt.% TaC alloys prepared by spark plasma sintering as well as ordinary sintering followed by hot rolling and annealing treatment, respectively, were investigated. Tensile tests indicate that below 600 °C there is no tensile plastic deformation while at 700 °C the total elongation of spark plasma sintered (SPSed) W-0.5 wt.% TaC is up to 36%, which is about 3.3 times that of spark plasma sintered W samples. In contrast, the tensile strength and total elongation of rolled W-0.5 wt.% TaC are 717 MPa and 10.7% at 250 °C, respectively. The ductile-brittle transition temperature (DBTT) of rolled W-0.5 wt.% TaC is between 200 °C and 250 °C, about 300 °C lower than that of spark plasma sintered W-0.5 wt.% TaC (~ 600 °C). Annealing decreases the DBTT (~ 200 °C) and improves thermal conductivity from 175 to 186 W/m·K at room temperature. Microstructure analyses indicates that TaC could purify and strengthen grain boundaries by capturing impurity oxygen in tungsten to form Ta 2 O 5 . The results indicate that strength, ductility and thermal conductivity can be improved by purifying, hot rolling and subsequent annealing. [ABSTRACT FROM AUTHOR]

The chlorine atom (Cl·) has a high potential to perturb atmospheric photochemistry by oxidizing volatile organic compounds (VOCs), but the exact role it plays in the polluted troposphere remains unclear. The Master Chemical Mechanism (MCM) is a near-explicit mechanism that has been widely applied in the atmospheric chemistry research. While it addresses comprehensively the chemistry initiated by the OH, O3 and NO3 radicals, its representation of the Cl · chemistry is incomplete as it only considers the reactions for alkanes. In this paper, we develop a more comprehensive Cl · chemistry module that can be directly incorporated within the MCM framework. A suite of 205 chemical reactions describes the Cl ·-initiated degradation of alkenes, aromatics, alkynes, aldehydes, ketones, alcohols, and some organic acids and nitrates, along with the inorganic chemistry involving Cl · and its precursors. To demonstrate the potential influence of the new chemistry module, it was incorporated into a MCM box model to evaluate the impacts of nitryl chloride (ClNO2), a product of nocturnal halogen activation by nitrogen oxides (NOX), on the following day's atmospheric photochemistry. With constraints of recent observations collected at a coastal site in Hong Kong, southern China, the modeling analyses suggest that the Cl · produced from ClNO2 photolysis may substantially enhance the atmospheric oxidative capacity, VOC oxidation and O3 formation, particularly in the early morning period. The results demonstrate the critical need for photochemical models to include more detailed chlorine chemistry in order to better understand the atmospheric photochemistry in polluted environments subject to intense emissions of NOX, VOCs and chlorine-containing constituents. [ABSTRACT FROM AUTHOR]

This paper presents details of the University of Colorado (CU) Pilatus unmanned research aircraft, assembled to provide measurements of aerosols, radiation and thermodynamics in the lower troposphere. This aircraft has a wingspan of 3.2 m and a maximum take off weight of 25 kg and is powered by an electric motor to reduce engine exhaust and concerns about carburetor icing. It carries instrumentation to make measurements of broadband up- and downwelling shortwave and longwave radiation, aerosol particle size distribution, atmospheric temperature, relative humidity and pressure and to collect video of flights for subsequent analysis of atmospheric conditions during flight. In order to make the shortwave radiation measurements, care was taken to carefully position a high-quality compact inertial measurement unit (IMU) and characterize the attitude of the aircraft and it's orientation to the upward looking radiation sensor. Using measurements from both of these sensors, a correction is applied to the raw radiometer measurements to correct for aircraft attitude and sensor tilt relative to the sun. The data acquisition system was designed from scratch based on a set of key driving requirements to accommodate the variety of sensors deployed. Initial test flights completed in Colorado provide promising results with measurements from the radiation sensors agreeing with those from a nearby surface site. Additionally, estimates of surface albedo from onboard sensors were consistent with local surface conditions, including melting snow and bright runway surface. Aerosol size distributions collected are internally consistent and have previously been shown to agree well with larger, surface-based instrumentation. Finally the atmospheric state measurements evolve as expected, with the near-surface atmosphere warming over time as the day goes on, and the atmospheric relative humidity decreasing with increased temperature. No directional bias on measured temperature, as might be expected due to uneven heating of the sensor housing over the course of a racetrack pattern, was detected. The results from these flights indicate that the CU Pilatus platform is capable of performing research grade lower tropospheric measurement missions. [ABSTRACT FROM AUTHOR]

The silkworm, Bombyx mori, is an economically important insect that was domesticated more than 5000 years ago. Its major economic traits focused on by breeders are quantitative traits, and an accurate and efficient QTL mapping method is necessary to explore their genetic architecture. However, current widely used QTL mapping models are not well suited for silkworm because they ignore female achiasmate and gender effects. In this study, we propose a composite method combining rational population selection and special mapping methods to map QTL in silkworm. By determining QTL for cocoon shell weight ( CSW), we demonstrated the effectiveness of this method. In the CSW mapping process, only 56 markers were used and five loci or chromosomes were detected, more than in previous studies. Additionally, loci on chromosomes 1 and 11 dominated and accounted for 35.10% and 15.03% of the phenotypic variance respectively. Unlike previous studies, epistasis was detected between loci on chromosomes 11 and 22. These mapping results demonstrate the power and convenience of this method for QTL mapping in silkworm, and this method may inspire the development of similar approaches for other species with special genetic characteristics. [ABSTRACT FROM AUTHOR]

The Time Of internally Reflected Cherenkov light (TORCH) detector is under development. Charged particle tracks passing through a 1 cm plate of quartz will generate the Cherenkov photons, and their arrival will be timed by an array of micro-channel plate photon detectors. As part of the TORCH R&D studies, commercial and custom-made micro-channel plate detectors are being characterized. The final photon detectors for this application are being produced in a three-phase program in collaboration with industry. Custom-made single-channel devices with extended lifetime have been manufactured and their performance is being systematically investigated in the laboratory. Optical studies for the preparation of beam and laboratory tests of a TORCH prototype are also underway. [ABSTRACT FROM AUTHOR]

The chlorine atom (Cl·) has a high potential to perturb atmospheric photochemistry by oxidizing volatile organic compounds (VOCs), but the exact role it plays in the polluted troposphere remains unclear. The Master Chemical Mechanism (MCM) is a near explicit mechanism that has been widely applied in the atmospheric chemistry research. While it addresses comprehensively the chemistry initiated by the OH, O3 and NO3 radicals, its representation of the Cl· chemistry is incomplete as it only considers the reactions for alkanes. In this paper, we develop a more comprehensive Cl· chemistry module that can be directly incorporated within the MCM framework. A suite of 199 chemical reactions describes the Cl·-initiated degradation of alkenes, aromatics, aldehydes, ketones, alcohols, and some organic acids and nitrates, along with the inorganic chemistry involving Cl· and its precursors. To demonstrate the potential influence of the new chemistry module, it was incorporated into a MCM box model to evaluate the impacts of nitryl chloride (ClNO2), a product of nocturnal halogen activation by nitrogen oxides (NOx), on the following-day's atmospheric photochemistry. With constraints of recent observations collected at a coastal site in Hong Kong, southern China, the modeling analyses suggest that the Cl· produced from ClNO2 photolysis may substantially enhance the atmospheric oxidative capacity, VOC oxidation, and O3 formation, particularly in the early morning period. The results demonstrate the critical need for photochemical models to include more fully chlorine chemistry in order to better understand the atmospheric photochemistry in polluted environments subject to intense emissions of NOx, VOCs and chlorine-containing constituents. [ABSTRACT FROM AUTHOR]

Toll-like receptors ( TLRs), an important family of pattern-recognition receptors, and antimicrobial peptides ( AMPs) contribute to the first line of innate protection of mammals against microbes. To compare characteristics of innate immunity between Tibetan and Yorkshire pigs, we investigated the mRNA abundance of TLR genes ( TLR1- TLR9) and two AMP-encoding genes ( PBD-1 and PR-39) in thymus, spleen, blood, palatine tonsils, and mesenteric and pulmonary hilar lymph nodes of the two breeds at ages of 6, 12 and 24 weeks using quantitative real-time PCR. Results showed that all mRNAs were detected in all tissues. Transcript levels of the major TLR genes of Tibetan pigs were significantly higher than those of Yorkshires in most tissues of the immune system, with a higher abundance of porcine ( PBD-1) ( beta-defensin-1) and PR-39 mRNA in lymphoid organs and tissues, especially blood, palatine tonsils, and mesenteric and pulmonary hilar lymph nodes. Our data suggest that Tibetan pigs have stronger innate immunity for triggering local and/or systemic immune responses to eliminate infections with pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

Decitabine, which reverses hypermethylation of the p15INK4B gene in vitro, has been used to relieve cytopenias and blast excess in over 50% of patients with high-risk myelodysplastic syndrome (MDS). In this study, heme oxygenase-1 (HO-1) was overexpressed in MDS cell line SKM-1, which was closely related to resistance to decitabine-induced apoptosis. We aimed to further investigate the role of HO-1 in apoptosis induced by low-dose decitabine in SKM-1 cells. Upregulation of HO-1 by transfecting it into SKM-1 cells with lentivirus vector promoted cell proliferation and protected them against apoptosis. In contrast, downregulation of HO-1 enhanced decitabine-induced apoptosis but reduced accumulation of the S phase in cell cycle. To explore the mechanism, the expressions of cell cycle-related proteins were detected after the cells were treated by decitabine in each group. p15INK4B and CDK4 were overexpressed in SKM-1 cells in which HO-1 was inhibited, and the expression-depending apoptosis was related to the caspase-3 pathway. Even though HO-1 was silenced, the apoptotic rate never increased as the caspase-3 pathway was blocked. It is well known that p15INK4B dominantly regulates the S phase of the cell cycle. p15INK4B was herein demethylated more evidently in the group of SKM-1 cells in which HO-1 was downregulated, as well as in the mononuclear cells of patients suffering from MDS. In the case of poor prognosis, the mRNA level of HO-1 was raised. In conclusion, overexpression of HO-1 indicated resistance to demethylation of p15INK4B induced by decitabine. [ABSTRACT FROM AUTHOR]

The role of sulphuric acid (H2SO4) in fabrication graphene oxide besides as intercalant has not been well addressed. In this work, Raman spectroscopy is used to monitor structural evolution in chemical vapor deposition (CVD) graphene chemically oxidized by dilute H2SO4. From the analysis of Raman spectra of oxidized graphene, we propose that oxidation first initiates at preexisting defects, and vacancy-like defects are formed. Following is the radial growth of the vacancy, and oxidation pits appear in graphene. This assumption is further confirmed by atomic force microscope measurement. It is also found that with increase of amounts of defects, G peak is blue shift, and this is explained by defect and hole doping effect. Hole doping in graphene is much stronger at hexagon regions near the oxidation pits. This work helps in understanding the role of H2SO4 in fabrication graphene oxide as oxidizer as well as helps in obtaining structure information of graphene oxide. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Irregularly shaped (IRS) particles widely exist in many engineering and industrial fields. The macro physical and mechanical properties of the particle system are governed by the interaction between the particles in the system. The interaction between IRS particles is more complicated because of their complex geometric shape with extremely irregular and co-existed concave and convex surfaces. These particles may interlock each other, making the sliding and friction of IRS particles more complex than that of particles with regular shape. In order to study the interaction of IRS particles more efficiently, a refined method of constructing discrete element model based on computed tomography scanning of IRS particles is proposed. Three parameters were introduced to control the accuracy and the number of packing spheres. Subsequently, the inertia tensor of the IRS particle model was optimized. Finally, laboratory and numerical open bottom cylinder tests were carried out to verify the refined modeling method. The influence of particle shape, particle position, and mesoscopic friction coefficient on the interaction of particles was also simulated. It is noteworthy that with the increase of mesoscopic friction coefficient, the fluidity of IRS particle assembly decreases, and intermittent limit equilibrium state may appear. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

TORCH is an innovative high-precision time-of-flight system to provide particle identification in the difficult intermediate momentum region up to 10 GeV/ c . It is also suitable for large-area applications. The detector provides a time-of-flight measurement from the imaging of Cherenkov photons emitted in a 1 cm thick quartz radiator. The photons propagate by total internal reflection to the edge of the quartz plate and are then focused onto an array of photon detectors at the periphery. A time-of-flight resolution of about 10–15 ps per incident charged particle needs to be achieved to allow a three sigma kaon-pion separation up to 10 GeV/ c momentum for the TORCH located 9.5 m from the interaction point. Given ~ 30 detected photons per incident charged particle, this requires measuring the time-of-arrival of individual photons to about 70 ps. This paper will describe the design of a TORCH prototype involving a number of ground-breaking and challenging techniques. [ABSTRACT FROM AUTHOR]

The experiment was conducted to investigate the effects of dietary supplementation of fulvic acid on lipid metabolism of finishing pigs. One hundred eighty crossbred barrows (Landrace x Yorkshire, 60 ± 2.5 kg) were randomly allotted to 5 dietary treatments (36 pigs/treatment) and fed a basal diet supplemented with 0, 0.2%, 0.4%, 0.6%, and 0.8% fulvic acid for 42 d. Thirty pigs (6 pigs/treatment) were slaughtered at the end of the experiment. Blood samples and adipose tissue were collected for determination of blood parameters and lipid metabolic enzymes. The results showed that compared with the control group, dietary supplementation of 0.2%, 0.4%, and 0.6% fulvic acid significantly reduced mean backfat thickness of pigs (P < 0.05). The serum concentrations of low-density lipoprotein, leptin, growth hormone, insulin, and tri-iodothyronine were significantly increased by adding fulvic acid in diets (P < 0.05). With the raised concentration of dietary fulvic acid, hormone sensitive lipase (HSL) activity was significantly increased (P < 0.05), and lipoprotein lipase (LPL) activity was significantly decreased (P < 0.05) in adipose tissue. In conclusion, dietary supplementation of fulvic acid reduced the mean backfat thickness of pigs. This change related to the increased activity of HSL and the decreased activity of LPL in adipose tissue. [ABSTRACT FROM AUTHOR]

Net primary production (NPP) is commonly used to measure productivity of steppe grasses and has been extensively studied. However, NPP variations within an enclosed watershed as influenced by precipitation and environmental factors (e.g., soils) have been poorly documented in existing literature. The objectives of this study were to: (1) examine spatiotemporal variations of NPP across a Eurasian typical steppe watershed using remote sensing and field data, and (2) determine effects of precipitation on the spatiotemporal variations. In addition to the Moderate Resolution Imaging Spectroradiation (MODIS) data from 2000 to 2010, field data on NPP, soils, and groundwater were measured by the authors in 2012 and used in this study. Advanced statistical (e.g., Mann-Kendall and correlation) and visualization techniques were employed to analyze the data. The results indicate that the NPP for a downstream area within the study watershed tended to be smaller than the NPP for an upstream area. The NPP varied almost synchronically with precipitation and was especially dependent on the May to July precipitation for a given year. The May to July precipitation could explain 12% to 65% of the NPP variances and played more roles in the growth of steppe grasses in a lower area than in an upper area. The NPP spatial pattern and the spatially differentiated effects of precipitation might be controlled by environmental factors of topography, soil texture, soil permeability, soil salinity, and grazing intensity. [ABSTRACT FROM AUTHOR]

To increase the corrosion resistance of tungsten, W-Cr-C coatings were fabricated on the tungsten matrix with spark plasma sintering (SPS) method from graphite and chromium powders. SEM and XRD analysis illustrated that W-Cr-C coatings with a thickness of 25 µm were composed of tungsten carbide layer and chromium carbide (Cr7C3 and Cr3C2) particles distributed in the surface layer of the coatings. The incorporation of chromium carbide largely enhanced the compactness of coating surface and refined the WC grains. In the immersion experiments, W-Cr-C composite coating exhibited better corrosion resistance than pure WC coating after exposure to the de-ionized water for 38 days at both room temperature and 60 °C. Electrochemical measurement showed that the reinforcement of chromium carbides can largely improve the corrosion resistance of WC coating in a 3.5% NaCl solution. [ABSTRACT FROM AUTHOR]

Salivary gland tumors (SGT) are a group of highly heterogeneous head and neck malignancies with widely varied clinical outcomes and no standard effective treatments. The CRTC1-MAML2 fusion oncogene, encoded by a recurring chromosomal translocation t(11;19)(q14-21;p12-13), is a frequent genetic alteration found in >50% of mucoepidermoid carcinomas (MEC), the most common malignant SGT. In this study, we aimed to define the role of the CRTC1-MAML2 oncogene in the maintenance of MEC tumor growth and to investigate critical downstream target genes and pathways for therapeutic targeting of MEC. By performing gene expression analyses and functional studies via RNA interference and pharmacological modulation, we determined the importance of the CRTC1-MAML2 fusion gene and its downstream AREG-EGFR signaling in human MEC cancer cell growth and survival in vitro and in vivo using human MEC xenograft models. We found that CRTC1-MAML2 fusion oncogene was required for the growth and survival of fusion-positive human MEC cancer cells in vitro and in vivo. The CRTC1-MAML2 oncoprotein induced the upregulation of the epidermal growth factor receptor (EGFR) ligand Amphiregulin (AREG) by co-activating the transcription factor CREB, and AREG subsequently activated EGFR signaling in an autocrine manner that promoted MEC cell growth and survival. Importantly, CRTC1-MAML2-positive MEC cells were highly sensitive to EGFR signaling inhibition. Therefore, our study revealed that aberrantly activated AREG-EGFR signaling is required for CRTC1-MAML2-positive MEC cell growth and survival, suggesting that EGFR-targeted therapies will benefit patients with advanced, unresectable CRTC1-MAML2-positive MEC. [ABSTRACT FROM AUTHOR]

Background: Psychiatric disorders are common in chronic disease states; intestinal transplantation recipients may therefore be at high risk for psychiatric disorder (PD). We sought to investigate the frequency and type of PD in our cohort of patients undergoing transplantation between 2007 and 2012. Results: The notes of 25 patients who had undergone transplantations since 2007 were available for analysis. Five of 25 patients had died at the time of data collection. Pretransplantation, 14 of 25 patients had a history of a single psychiatric disorder (SPD) (depression). Two of 25 had double psychiatric diagnoses (DPD; depression with anxiety), and 1 had three PDs. Three of 25 patients suffered from chronic pain syndrome and 1 patient had this as an isolated diagnosis without any other PD. Post-transplantation, 10 of 14 patients still had an SPD; however, 3 of 14 had acquired a second diagnosis (DPD; anxiety with depression) with suicidal ideation in 2 cases. Those with DPD preoperatively did not improve. Depression resolved in 1 of 14 after transplantation. One patient without a history of psychiatric issues developed DPD during the postoperative course. Only 3 of 25 surviving patients are free of any psychological diagnosis post-transplantation. The presence of other problems in the cohort such as chronic pain syndrome in 4 of 25, medical noncompliance in 3 of 25, cyclizine dependency in 2 of 25, and recreational drug use suspected in 1 were also identified. Problems with body image relating to the stoma were experienced by 2 of 25 patients. Conclusion: The incidence of psychiatric disorder in patients embarking on transplantation is high and relates to their history of chronic illness. The additional stress of the transplantation operation and the long in-hospital rehabilitation period takes its toll on patients' emotional health and many acquire further psychiatric diagnoses. Managing the psychiatric health of patients is important for successful rehabilitation and their long-term health and wellbeing. [ABSTRACT FROM AUTHOR]

Highlights: [•] The 9Cr-ODS alloy powders were prepared by sol–gel method combining with the chemical reduction and ball-milling. [•] The 9Cr-ODS ferritic/martensitic steel was sintered by SPS using a restructured dies. [•] Thermal treatment can greatly improve the mechanical performance of 9Cr-ODS steel. [ABSTRACT FROM AUTHOR]

This exploratory quasi-experimental evaluation assessed the effectiveness of the use of a concrete discussion guide to promote organisation-wide application of a partnering approach to engage older home-care clients with chronic disease/disabilities as care partners. A post-test-only design with an independent pre-test sample was used to compare selected outcomes with those of standard in-home care. The theoretically informed discussion guide portrayed how to go about the process of empowering partnering by using language and open-ended conversational leads to construct partnering, partnering effort and health as a resource for everyday living through social interaction. The discussion guide was provided to all providers for use with all clients in one home-care programme in Ontario, Canada and this organisation was compared with a similar but geographically distanced organisation, also in Ontario. Seven hundred and ninety-one randomly selected clients (mean age = 72.5 years) receiving 3+ months of in-home care for chronic conditions/disabilities from the two home-care programmes between September 2007 and May 2010 completed a researcher-administered questionnaire at either baseline, 1 year or 2 years. Instruments included the Client's Partnering Experience, Health-Promoting Partnering Effort, a modified version of Locus of Authority in Decision-Making, the Medical Outcomes Survey Self-Rated Health Scale, Health and Social Services Utilization and a modified Functional Independence Measure. Analysis of covariance revealed that the use of the concrete discussion guide to promote organisation-wide application of a partnering approach achieved significantly greater client partnering experience and health-promoting partnering effort over time than did the usual approach to in-home-care interactions. Using the discussion guide enhanced client/provider partnering, hence, interdependence, contributing positively to promoting clients' health as a resource for everyday living. [ABSTRACT FROM AUTHOR]

Recently we showed that the transcription activator At MYB44 regulates expression of EIN2, a gene essential for ethylene signalling and insect resistance, in Arabidopsis thaliana ( Arabidopsis). To link the transactivation with insect resistance, we investigated the wild-type and atmyb44 mutant plants, genetically Complemented atmyb44 ( Catmyb44) and AtMYB44- Overexpression Transgenic Arabidopsis ( MYB44OTA). We found that AtMYB44 played a critical role in Arabidopsis resistance to the phloem-feeding generalist green peach aphid ( Myzus persicae Sulzer) and leaf-chewing specialist caterpillar diamondback moth ( Plutella xylostella L.). AtMYB44 was required not only for the development of constitutive resistance but also for the induction of resistance by both herbivorous insects. Levels of constitutive and herbivore-induced resistance were consistent with corresponding amounts of the At MYB44 protein constitutively produced in MYB44OTA and induced by herbivory in Catmyb44. In both cases, At MYB44 promoted EIN2 expression to a greater extent in MYB44OTA than in Catmyb44. However, At MYB44-promoted EIN2 expression was arrested with reduced resistance levels in the EIN2-deficient Arabidopsis mutant ein2-1 and the MYB44OTA ein2-1 hybrid. In the different plant genotypes, only MYB44OTA constitutively displayed phloem-based defences, which are specific to phloem-feeding insects, and robust expression of genes involved in the biosynthesis of glucosinolates, which are the secondary plant metabolites known as deterrents to generalist herbivores. Phloem-based defences and glucosinolate-related gene expression were not detected in ein2-1 and MYB44OTA ein2-1. These results establish a genetic connection between the regulatory role of AtMYB44 in EIN2 expression and the development of Arabidopsis resistance to insects. [ABSTRACT FROM AUTHOR]

A rapid and sensitive H7 and N9 subtype-specific reverse transcription loop-mediated isothermal amplification assay was developed respectively for visual detection of human-infected influenza A ( H7 N9) virus. The reaction was performed in one step in a single tube at 63°C for 60 min with the addition of hydroxynaphthol blue dye before amplification. The detection limits of both subtype-specific assays were comparable to those of validated H7 and N9 real-time PCR assays respectively and no cross-detection was observed with influenza A pandemic H1 N1, H3 N2, H5 N1, H9 N2 or influenza B virus. The assays were evaluated further with H7 N9 virus-infected clinical specimens. [ABSTRACT FROM AUTHOR]

The article presents a study that evaluates the performance of the Single Particle Soot Photometer (SP2) and the Integrating Sphere/Integrating Sandwich Spectrophotometer (ISSW) in measuring the concentration of refractory black carbon (BC) in snow. It found that the SP2 can be used to measure the size distribution and mass concentration of BC in the snow. It suggests that estimates of BC mass concentration may be associated with significant underestimates of uncertainty.

The article presents a study which assesses the measurement techniques in quantifying the concentration of refractory black carbon (BC) in snow samples. The comparison of the Single Particle Soot Photometer (SP2) and the Integrating Sphere/Integrating Sandwich Spectrophotometer (ISSW) in the quantification of BC concentration is outlined. Underestimates of uncertainty in the measurement of BC concentration using SP2 or ISSW are investigated.

Background: Acute liver failure (ALF) is characterized by impaired regeneration of hepatocytes, partially resulting from the defective signaling between elevated levels of hepatocyte growth factor (HGF) and the downregulation of its receptor, c-met.Aims: In this study, we assess the therapeutic efficacy of in vivo c-met gene transfer in ALF.Methods: We established a D: -galactosamine/lipopolysaccharide (D: -GalN/LPS)-induced ALF model in rats. The levels of HGF and c-met in D: -GalN/LPS rats were compared with vehicle-injected rats and those undergoing liver regeneration following partial hepatectomy (PH). To deliver c-met in vivo, pcDNA-c-met was constructed and transfected into the rat liver via hydrodynamic injection. Control rats were transfected with the pcDNA3.1 plasmid. The expressions of c-met in different tissues were examined by immunohistochemistry. Hepatocyte proliferation and apoptosis were determined by PCNA staining and TUNEL assay, respectively. The survival of rats in the control and c-met-expressing rats was compared by Kaplan-Meier analysis.Results: Compared with control rats, D: -GalN/LPS or PH -treated rats had significantly higher levels of HGF (P < 0.01). D: -GalN/LPS also led to significantly lower c-met expression in the liver (P < 0.01) than PH. The in vivo c-met gene transfer led to its specific expression on hepatocytes, which was accompanied by the enhancement of hepatocyte proliferation, a reduction in apoptosis, as well as significant improvement in overall survival (P < 0.01).Conclusions: This study provides the initial evidence that c-met may serve as a novel target for gene therapy, and may be of clinical benefit in the treatment of patients with ALF. [ABSTRACT FROM AUTHOR]

Abstract: The Linear Collider Flavour Identification (LCFI) Collaboration is developing the sensors, readout electronics and mechanical support structures for the vertex detector of the International Linear Collider (ILC). High speed readout is needed to ensure that the occupancy due to the pair production background at the ILC is kept below the 1% level. In order to satisfy this requirement, Column Parallel CCDs (CPCCDs), Column Parallel Readout chips (CPRs) and Column Parallel Driver chips (CPDs) have been developed. The CPCCD has to operate at a clock frequency of 50MHz, which represents a difficult technical challenge due to the large sensor capacitance. The design and performance of the second generation CPCCD sensors, CPC2, and the new driver chip, CPD1, which meet these challenging requirements, are described. [ABSTRACT FROM AUTHOR]

In the lowermost layer of the atmosphere—the troposphere—ozone is an important source of the hydroxyl radical, an oxidant that breaks down most pollutants and some greenhouse gases. High concentrations of tropospheric ozone are toxic, however, and have a detrimental effect on human health and ecosystem productivity. Moreover, tropospheric ozone itself acts as an effective greenhouse gas. Much of the present tropospheric ozone burden is a consequence of anthropogenic emissions of ozone precursors resulting in widespread increases in ozone concentrations since the late 1800s. At present, east Asia has the fastest-growing ozone precursor emissions. Much of the springtime east Asian pollution is exported eastwards towards western North America. Despite evidence that the exported Asian pollution produces ozone, no previous study has found a significant increase in free tropospheric ozone concentrations above the western USA since measurements began in the late 1970s. Here we compile springtime ozone measurements from many different platforms across western North America. We show a strong increase in springtime ozone mixing ratios during 1995–2008 and we have some additional evidence that a similar rate of increase in ozone mixing ratio has occurred since 1984. We find that the rate of increase in ozone mixing ratio is greatest when measurements are more heavily influenced by direct transport from Asia. Our result agrees with previous modelling studies, which indicate that global ozone concentrations should be increasing during the early part of the twenty-first century as a result of increasing precursor emissions, especially at northern mid-latitudes, with western North America being particularly sensitive to rising Asian emissions. We suggest that the observed increase in springtime background ozone mixing ratio may hinder the USA’s compliance with its ozone air quality standard. [ABSTRACT FROM AUTHOR]

Abstract: The LCFI Collaboration is developing the sensors, readout electronics and mechanical support structures for the Vertex Detector (VXD) of the International Linear Collider (ILC). High-speed readout is needed to ensure that the occupancy due to the pair production background at the ILC is kept below 1% level. In order to satisfy this requirement, Column Parallel CCDs (CPCCDs) and Column Parallel Readout chips (CPRs) have been developed. The CPCCD has to operate at a clock frequency of 50MHz, which represents a difficult technical challenge due to the relatively large sensor capacitance. The design and performance of planar transformers, which can be used to provide the required 20A clock current, are described. [Copyright &y& Elsevier]

Abstract: The Linear Collider Flavour Identification (LCFI) collaboration has successfully developed the first prototype of a novel particle detector, the In-situ Storage Image Sensor (ISIS). This device ideally suits the challenging requirements for the vertex detector at the future International Linear Collider (ILC), combining the charge storing capabilities of the Charge-Coupled Devices (CCD) with readout commonly used in CMOS imagers. The ISIS avoids the need for high-speed readout and offers low power operation combined with low noise, high immunity to electromagnetic interference and increased radiation hardness compared to typical CCDs. The ISIS is one of the most promising detector technologies for vertexing at the ILC. In this paper we describe the measurements on the charge-shielding properties of the p-well, which is used to protect the storage register from parasitic charge collection and is at the core of device''s operation. We show that the p-well can suppress the parasitic charge collection by almost two orders of magnitude, satisfying the requirements for the application. [Copyright &y& Elsevier]

In this paper a carbon ionic liquid electrode (CILE) was fabricated by using a room temperature ionic liquid of 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) as binder. By using the CILE as basal electrode, the hemoglobin (Hb) molecule was immobilized on the surface of CILE with a sodium alginate (SA) hydrogel and SiO2 nanoparticles organic-inorganic composite material. The direct electrochemical behaviors of Hb in the bionanocomposite film were further studied in a pH 7.0 Britton-Robinson (B-R) buffer solution. A pair of well-defined quasi-reversible cyclic voltammetric peaks of Hb was obtained on SA/nano-SiO2/Hb/CILE with the formal potential (E0') at -0.355 V (vs. SCE), which was the characteristic of heme Fe(III)/Fe(II) redox couples. The formal potential of Hb Fe(III)/Fe(II) couple shifted negatively with increasing pH of solution with a slope of -45.2 mV/pH, which indicated that a one electron transfer accompanied with one proton transportation. The immobilized Hb showed good electrocatalytic manner to the reduction of trichloroacetic acid (TCA). [ABSTRACT FROM AUTHOR]

Abstract: The In Situ Storage Image Sensor (ISIS) is a monolithic active pixel sensor with memory cells in each pixel. The memory cells are implemented as a CCD register. A test device with parameters suitable for tracking charged particles has been constructed and characterized. The characteristics of a proof-of-principle ISIS device are described and results from using the sensor as a tracking device for high energy electrons are presented. [Copyright &y& Elsevier]

Abstract: The in situ storage image sensor (ISIS) is a monolithic active pixel sensor with memory cells in each pixel. The memory cells are implemented as a CCD register. This and other features of the sensor make the ISIS an excellent device for detectors that will be used at the International linear collider (ILC), an electron-positron accelerator with a proposed centre-of-mass energy of around 500GeV. The sensor can be made very thin while retaining a high signal-to-noise ratio. The memory cells can be read out between bunch trains at a relatively low clock speed, hence limiting power consumption. The actual signal charge is stored in potential wells and not on capacitors, minimizing the sensitivity to electromagnetic interference. This paper presents the results of the first beam test of the first ISIS prototype. The measurements made include the signal-to-noise ratio, position resolution and efficiency. [Copyright &y& Elsevier]

It has been verified that carvedilol can attenuate myocardial no-reflow. However, the effects of carvedilol on adenosine triphosphate-sensitive K+ (KATP) channel and endothelin-1 (ET-1) are unknown. Forty mini-swines were randomized into 5 study groups: 8 control, 8 carvedilol pretreatment, 8 glibenclamide (KATP channel blocker)-treated, 8 carvedilol and glibenclamidepre- treated and 8 sham-operated. An acute myocardial infarction(AMI) and reperfusion model was created with a three-hour occlusion of the left anterior descending coronary artery followed by one-hour reperfusion. Compared with the control group, carvedilol significantly decreased the area of no-reflow (myocardial contrast echocardiography: from 78.5±4.5% to 24.9±4.1%, pathological means: from 82.3±1.9% to 25.8±4.3% of ligation area, respectively; all p < 0.01) and reduced necrosis size from 98.5±1.3% to 74.4±4.7% of ligation area, p < 0.05). It also decreased plasma ET-1 and myocardial tissue ET-1. However, glibenclamide abrogated the protective effect of carvedilol. The beneficial effect of carvedilol on myocardial no-reflow could be due to its effect on ET-1 via the activation of the KATP channel. Perfusion (2008) 23, 111-115. [ABSTRACT FROM AUTHOR]

Abstract: Samples La1− a Ag a MnO3 (0.05⩽a⩽0.50) were sol–gel fabricated. A part of Ag was found to dissociate and run off the samples in sintering process when sintering temperature exceeds 700°C, resulting in a composite of La1− x Ag x MnO3 and MnO2/Mn2O3. The magnetic and transport properties of the composite have been studied. The sample with the nominal composition La0.7Ag0.3MnO3 was found to show the greatest magnetoresistance in the sample group. Detailed analysis on average Mn valence reveals a composite of (La0.985Ag0.015MnO3)0.776[(MnO2)0.590(Mn2O3)0.410]0.224. Its MR ratio at room temperature exceeds 24% under a field of 1.8T. A conductivity leap has been observed around a=0.30. It suggests a kind of field-induced fluctuation in percolation in the samples investigated. [Copyright &y& Elsevier]

Epidermal growth factor receptor (EGF-R) signaling is essential for proper fetal development and growth of pancreatic islets, and there is also evidence for its involvement in beta-cell signal transduction in the adult. To study the functional roles of EGF-R in beta-cell physiology in postnatal life, we have generated transgenic mice that carry a mutated EGF-R under the pancreatic duodenal homeobox-1 promoter (E1-DN mice). The transgene was expressed in islet beta- and delta-cells but not in alpha-cells, as expected, and it resulted in an approximately 40% reduction in pancreatic EGF-R, extracellular signal-related kinase, and Akt phosphorylation. Homozygous E1-DN mice were overtly diabetic after the age of 2 weeks. The hyperglycemia was more pronounced in male than in female mice. The relative beta-cell surface area of E1-DN mice was highly reduced at the age of 2 months, while alpha-cell surface area was not changed. This defect was essentially postnatal, since the differences in beta-cell area of newborn mice were much smaller. An apparent explanation for this is impaired postnatal beta-cell proliferation; the normal surge of beta-cell proliferation during 2 weeks after birth was totally abolished in the transgenic mice. Heterozygous E1-DN mice were glucose intolerant in intraperitoneal glucose tests. This was associated with a reduced insulin response. However, downregulation of EGF-R signaling had no influence on the insulinotropic effect of glucagon-like peptide-1 analog exendin-4. In summary, our results show that even a modest attenuation of EGF-R signaling leads to a severe defect in postnatal growth of the beta-cells, which leads to the development of diabetes. [ABSTRACT FROM AUTHOR]

Background and purpose: Simvastatin, a cholesterol-lowering agent, can protect against endothelial dysfunction. However, the effects of simvastatin treatment on the restoration of blood flow to ischemic myocardium are not known. This study sought to assess such effects of simvastatin on an experimental model of myocardial no-reflow and to explore possible mechanisms. Experimental approach: Coronary ligation area and area of no-reflow were determined by myocardial contrast echocardiography in vivo and by histology in mini-pigs randomized into 7 study groups: controls, pretreated with simvastatin for 2 days, treated with 5-hydroxydecanoate (5-HD, the selective mitochondrial KATP channel blocker), treated with simvastatin + 5-HD, treated with HMR 1883 (the selective sarcolemmal KATP channel blocker), treated with simvastatin + HMR 1883 and a sham-operated group. The myocardial no-reflow model was induced with 3 h occlusion of the left anterior descending coronary artery followed by 2 h reperfusion. Key results: Compared with the control group, simvastatin significantly increased coronary blood flow, decreased the area of no-reflow assessed echocardiographically and reduced the necrotic area, by histology. There was no significant difference in these outcomes between simvastatin and simvastatin + HMR 1883 groups. In contrast, 5-HD abolished the effect of simvastatin. Conclusions and implications: Simvastatin can reduce the area and myocardial no-reflow after ischaemia and reperfusion. This beneficial effect is due to its activation of mitochondrial KATP channels. [ABSTRACT FROM AUTHOR]

Objective: To compare the effects of an aspirin-clopidogrel combination with those of the specific glycoprotein IIb/IIIa inhibitor tirofiban on myocardial no-reflow, nitric oxide concentration and activity of nitric oxide synthase (NOS) isoforms in a mini-swine model of acute myocardial infarction and reperfusion. Methods: Area of no-reflow was determined by both myocardial contrast echocardiography and pathological means in 40 mini-swine randomly assigned to five study groups: eight controls, eight pretreated with aspirin-clopidogrel combination for three days, eight given an intravenous infusion of tirofiban, eight treated with ischaemic preconditioning and eight sham operated. The acute myocardial infarction and reperfusion model was created with 3 h occlusion of the left anterior descending coronary artery followed by 1 h reperfusion. Results: Compared with the control group, tirofiban significantly decreased the area of no-reflow assessed echocardiographically and pathologically, from 78.5% to 22.8% and 82.3% to 23.2%, respectively (both p < 0.01), and increased blood nitric oxide concentration (p < 0.05), enhanced constitutive NOS activity from 0.51 to 0.81 U/mg protein and mRNA expression from 0.47% to 0.66%, but decreased inducible NOS activity from 0.76 to 0.41 U/mg protein and mRNA expression from 0.54% to 0.39% in reflow myocardium (all p < 0.05-0.01). In contrast, the aspirin-clopidogrel combination did not significantly modify the above parameters (all p > 0.05) except for decreasing inducible NOS activity from 0.76 to 0.39 U/mg protein (p < 0.01) and mRNA expression from 0.54% to 0.40% (p <0.05). Conclusions: Tirofiban is very effective in attenuating myocardial no-reflow; in contrast, aspirin-clopidogrel combination is totally ineffective. These findings also support the concept that endothelial protection, apart from platelet inhibition, contributes to the beneficial effect of tirofiban on myocardial no-reflow. [ABSTRACT FROM AUTHOR]

Organization of the IGHV genes (n=108) on single human chromosomes has been determined by detecting these sequences in single sperm using multiplex PCR amplification followed by microarray detection. A total of 374 single sperm samples from five Caucasian males were studied. Three deletion/insertion polymorphisms (Del I-Del III) with deletion allele frequencies ranging from 0.1 to 0.3 were identified. Del I is a previously reported polymorphism affecting three IGHV genes (IGHV1-8, IGHV3-9, and IGHV2-10). Del II affects a region 2-18?kb containing two pseudogenes IGHV(II)-28.1 and IGHV3-29, and Del III spans~21-53?kb involving genes IGHV4-39, IGHV7-40, IGHV(II)-40-1, and IGHV3-41. Deletion alleles of both Dels II and III were found in a heterozygous state, and therefore, could not be easily detected if haploid samples were not used in the study. Results of the present study indicate that deletions/insertions together with other possible chromosomal rearrangements may play an important role in forming the genetic structure of the IGHV region, and may significantly contribute to antibody diversity. Since these three polymorphisms are located within or next to the 3'half of the IGHV region, they may have an important role in the expressed IGHV gene repertoire during immune response.Genes and Immunity (2005) 6, 186-193. doi:10.1038/sj.gene.6364176 Published online 3 March 2005 [ABSTRACT FROM AUTHOR]

During a campaign to study ozone loss mechanisms in the Arctic stratosphere (SOLVE), several instruments on NASA's ER-2 aircraft observed a very low number density (0.1 l-1) of large, nitric-acid-containing particles that form the polar stratospheric clouds (PSCs). For effective physical and chemical characterization of these particles, the measurements from these instruments have to be intercompared and integrated. In particular, proper interpretation requires knowledge of the sampling characteristics of the particles into the instruments. Here, we present the calculation of the sampling characteristics of the one of the instruments on the ER-2, the NOAA NOy instrument. This instrument sampled ambient particles and gas from two forward-facing inlets located fore and aft on a particle-separation housing (the football) and measured total NOy in the sample. In recent studies, ambient aerosol mass has been estimated by the difference of the measurements of the two inlets with the assumption that the rear inlet observations represent the gas-phase NOy and small particles and the front inlet samples represent gas-phase NOy and all particle sizes with varied efficiency (anisokinetic sampling). This knowledge was derived largely from semiempirical relations and potential flow studies of the housing. In our study, we used CFD simulations to model the compressible flow conditions and considered noncontinuum effects in calculating particle trajectories. Our simulations show that the blunt body housing the inlets has a strong and complex interaction with the flow and particles sampled by the two inlets. The simulations show that the front inlet characteristics are influenced by the effect of the blunt body on the upstream pressure field. The rear inlet sampling characteristics are influenced both by the shape and size of the inlet and its location on the blunt body. These interactions result in calculated inlet characteristics that are significantly different from previously assumed values. Analysis of the SOLVE data, considering the ambient conditions and the calculated inlet sampling characteristics, in conjunction with thermodynamic growth modeling of super-cooled ternary solution (STS) particles, provides validation of the CFD results. [ABSTRACT FROM AUTHOR]

Seventy-eight patients with prior myocardial infarction and left ventricular dysfunction who underwent nitrate-augmented myocardial tomography were followed for 23 +/- 14 months. Event-free survival was 100% in 34 patients with myocardial viability who underwent coronary artery bypass grafting (CABG) and 53% in those who received medical therapy (p = 0.0008). Of the 44 patients without myocardial viability, event-free survival was not significantly different between patients who underwent CABG and those who received medical therapy (96% vs 90%, p = NS). [ABSTRACT FROM AUTHOR]

Copper alloys are promising heat sink materials in future fusion reactors owing to the high thermal conductivity and good mechanical properties at medium temperatures. In the present study, aiming at enhancing the strength of copper while keeping the high thermal conductivity, nanoscale W particle dispersion strengthened Cu alloys with different W content of 2 at% (2.6 vol%), 5 at% (6.5 vol%) and 8 at% (10.3 vol%) were fabricated through ball-milling and spark plasma sintering (SPS). The effects of nanoscale W particles on the microstructure, mechanical properties and thermal conductivity of the Cu–W alloys were investigated. The average size of tungsten particles dispersed in copper matrix is 43 nm. The dispersion of W nanoparticles in copper could significantly refine the grain and improve the strength of Cu alloys. The average grain size of Cu-2at%W, Cu-5at%W and Cu-8at%W is as small as 0.84 μm, 0.65 μm and 0.54 μm, respectively. The tensile strength of Cu-8at%W reaches 495 MPa and the elongation is 10.6% at room temperature. The grain size refinement of Cu–W alloys can be attributed to the pinning effects of nanoscale W particles dispersed in the Cu matrix. Although the addition of W nanoparticles leads to a decrease in thermal conductivity, the thermal conductivity for all Cu–W samples is still above 300 Wm-1K-1 at room temperature. • Cu–W alloys with high strength and excellent thermal conductivity were fabricated. • W nanoparticles significantly refine the grains and improve the strength of Cu. • The average particle size of W is 43 nm and the grain size of Cu–W is 500–900 nm. [ABSTRACT FROM AUTHOR]

Background: The extent to which breast conserving surgeries (BCS) and mastectomies are conducted in day surgery in Canada is unknown. This study explored temporal and age-related trends in the performance of breast cancer surgeries as day procedures. Hospital readmissions for day surgeries and in-patient surgeries were compared. Methods: Breast cancer separations between 1986 and 1999 treated by mastectomy or BCS were identified in the Discharge Abstract Database. Proportions of surgeries performed annually in day surgery were estimated nationally, provincially, and by age-strata. Thirty-day readmission rates, including the reasons for readmission, were compared for in-patient and day procedures. Results: Day surgery use increased from 8.7% to 41.0% between 1986 and 1999. Most of this increase was due to BCS (57% were done in day surgery in 1999). BCS conducted in day surgery was more common in women 40 to 69 years old in the 1980s; variation by age disappeared by 1996. Few mastectomies were done in day surgery (5.9% in 1999) and rates varied little by age strata. In 1986, 60% of day surgeries resulted in readmission and 44% in 1999. The most common readmission reasons for day surgery procedures were completion mastectomies, further BCS, or lymph node excision. Interpretation: Day surgery use for breast cancer surgery, particularly for BCS, has increased dramatically. As of the late 1990s, rates of BCS performed in day surgery no longer vary by age. Day surgery readmission rates were higher than for in-patient surgery and follow-up surgeries were the main readmission reasons. [ABSTRACT FROM AUTHOR]

A chemical ionization mass spectrometer instrument has been developed for in situ measurements of nitric acid (HNO[sub 3]) in the upper troposphere and lower stratosphere from the NASA WB-57 aircraft. Fast and sensitive measurements of HNO[sub 3] are achieved by using a low surface area heated Teflon sampling inlet and detection techniques that employ ion-molecule reactions. Sensitivity to HNO[sub 3] is determined in flight by adding HNO[sub 3] from a calibrated HNO[sub 3] permeation source into the sample air flow, and instrument background is measured by displacing ambient air from the sampling inlet with a flow of dry nitrogen in the sampling inlet. Instrument temperatures, pressures, and gas flows are controlled in flight to maintain a constant detection sensitivity in a changing ambient operating environment. The initial performance of this new instrument is evaluated using HNO[sub 3] and ozone data obtained between 6 and 19 km during the 1999 NASA Atmospheric Chemistry of Combustion Emissions Near the Tropopause mission. The data reveal a sensitivity of 0.73 Hz/pptv, a detection limit of 30 pptv for 10 s integration times, and a fast time response (<1 s). Further reductions in the background HNO[sub 3] signal will improve performance. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

• A high dense bulk ultrafine-grained (∼400 nm) W-ZrC-Re alloy is fabricated via a developed bottom-up powder metallurgy process. • This UFG alloy has uniform dispersion particles with the average particle size of ∼28 nm and number density of 1.48 × 1021 /m3. • This W-ZrC-Re alloy maintains its UFG microstructures as well as a high hardness (∼740 HV) even after annealing at 1500 °C for 1 h. A bulk ultrafine-grained (UFG) W-ZrC-Re alloy is fabricated via a developed bottom-up powder metallurgy process. The detailed fabrication processes including the mechanical alloying and spark plasma sintering have been introduced. The relative density of this UFG W-ZrC-Re is as high as 99.5 %, and the average grain size is about 0.4 μm and uniform dispersion particles with the average particle size of ∼28 nm and number density of 1.48 × 1021 /m3. The W-ZrC-Re exhibits high thermal stability that maintains its UFG microstructures as well as a high hardness (∼740 HV) even after annealing at 1500 °C for 1 h. This high thermal stability is attributed to the synergistic effects of the nano-sized ZrC particle pinning and Re solute drag, which demonstrates a good potential in the manufacturing of high-stabled UFG and even nanocrystalline W materials. [ABSTRACT FROM AUTHOR]

Presents research which measured the concentrations of hydrogen radicals in the middle and upper troposphere with those of non-methane hydrocarbons. Examination of processes that produce O3; Inability of data to explain observed radical concentrations; Photolysis of carbonyl and peroxide compounds; Production rate for ozone faster than previously thought; Implications.

Thermally induced residual stresses across the TSV-Cu/TiW/SiO 2 /Si interface in through‑silicon vias (TSVs) have raised serious concerns about mechanical and electrical reliability in 3D ICs. The lack of a nanometer-precision measurement technique for the TSV interfacial stress gradient makes the interface failure mechanism unclear. In this work, we propose an ion beam layer removal (ILR) method for determining the residual stress in the as-fabricated TSV-Cu/TiW/SiO 2 /Si interface on a nanoscale to facilitate identification of the failure mechanism of the TSV-Cu/TiW/SiO 2 /Si interface in as-fabricated TSVs. The measurement results showed that the residual stress fluctuates across the TSV-Cu/TiW/SiO 2 /Si interface and that both compressive stress and tensile stress existed within the interface system. Compressive stress occurred at all three interfaces, the TSV-Cu/TiW, TiW/SiO 2 , and SiO 2 /Si interfaces, but transitioned to tensile stress at a distance of 25–45 nm from these interfaces. The highest level of shear stress concentration appeared inside the TSV-Cu at a distance of approximately 45 nm from the TSV-Cu/TiW interface. This shear stress concentration explains the experimentally observed TSV interfacial cracking phenomenon. Graphic abstract Unlabelled Image • ILR method was used for determining the residual stress in the TSV-Cu/TiW/SiO 2 /Si interface. • The residual stress fluctuated across the TSV-Cu/TiW/SiO 2 /Si interface. • The highest level of shear stress appears inside Cu at a distance of 45 nm from the TSV-Cu/TiW interface. • The shear stress concentration explains the TSV interfacial cracking phenomenon. [ABSTRACT FROM AUTHOR]

a-plane InGaN/GaN multiple quantum wells of different widths ranging from 3 to 12 nm were grown on r-plane sapphire by metal organic chemical vapor deposition for investigation. The peak emission intensity of the photoluminescence (PL) reveals a decreasing trend as the well width increases from 3 to 12 nm. Low temperature (9 K) time-resolved PL study shows that the sample with 3-nm-thick wells has a better optical property with a fast exciton decay time of 0.57 ns. The results of cathodoluminescence and micro-PL scanning images for samples of different well widths further verify the more uniform and stronger luminescence intensity distribution observed for the samples of thinner quantum wells, indicating that the important growth parameters for a-plane InGaN/GaN multiple quantum wells could be dominated by the In fluctuation and crystal quality during the epitaxial growth. [ABSTRACT FROM AUTHOR]