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The DArk Matter Particle Explorer (DAMPE), a satellite-based cosmic ray and gamma-ray detector, was launched on December 17, 2015, and began its on-orbit operation on December 24, 2015. In this work we document the on-orbit calibration procedures used by DAMPE and report the calibration results of the Plastic Scintillator strip Detector (PSD), the Silicon-Tungsten tracKer-converter (STK), the BGO imaging calorimeter (BGO), and the Neutron Detector (NUD). The results are obtained using Galactic cosmic rays, bright known GeV gamma-ray sources, and charge injection into the front-end electronics of each sub-detector. The determination of the boundary of the South Atlantic Anomaly (SAA), the measurement of the live time, and the alignments of the detectors are also introduced. The calibration results demonstrate the stability of the detectors in almost two years of the on-orbit operation.

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical science. © The Author(s) 2019. Published by Oxford University Press.

Temporary strict emission control strategies were conducted to ensure good air quality for China's V-Day parade (August 20-September 3, 2015) in Beijing and nearby cities. The influence of the emission control on particle number size distribution (PNSD) was evaluated based on the long-term measurements of PNSD at a rural site (Shangdianzi) located northeast of Beijing. This study also presented the comparison results of PNSD during the parade in 2015 and the Olympics in 2008 (August 8-23), as well as the same period without strict emission control in 2010-2013 (August 20-September 3). Compared with the same period in 2010-2013 and 2008 Olympics, the accumulation mode particle number concentration showed a significant reduction in 2015, and the PM1 mass concentration decreased by approximately 60-90%. The alleviation of the PM1 was also associated with the weather conditions. The back trajectories analysis results showed that the southerly air mass passing through the polluted areas accounted for 14% of the total back trajectories in 2015, which contributed to approximately 60% in the other years. During the control period in 2015, there were six new particle formation (NPF) events observed, with a higher frequency, but a lower formation rate and growth rate than the same period in 2010-2013. The comparison of the condensation sink (CS), sulfuric acid, solar radiation and relative humidity among the different years indicated that at Shangdianzi station, the first factor in determining the NPF occurrence was the CS, and the second factor could be the concentration level of precursor vapors participating in the NPF event (e.g., sulfuric acid).

Increased atmospheric CO2 concentrations are driving changes in ocean chemistry at unprecedented rates resulting in ocean acidification, which is predicted to impact the functioning of marine biota, in particular of marine calcifiers. However, the precise understanding of such impacts relies on an analytical system that determines the mechanisms and impact of elevated pCO2 on the physiology of organisms at scales from species to entire communities. Recent work has highlighted the need within experiments to control all aspects of the carbonate system to resolve the role of different inorganic carbon species on the physiological responses observed across taxa in real-time. Presently however, there are limited options available for continuous quantification of physiological responses, coupled with real-time calculation of the seawater carbonate chemistry system within microcosm environments. Here, we describe and characterise the performance of a novel pCO2 membrane equilibrium system (the Membrane Inlet Infra-Red Gas Analyser, MI-IRGA) integrated with a continuous pH and oxygen monitoring platform. The system can detect changes in the seawater carbonate chemistry and determine organism physiological responses, while providing the user with real-time control over the microcosm system. We evaluate the systems control, response time and associated error, and demonstrate the flexibility of the system to operate under field conditions and within a laboratory. We use the system to measure physiological parameters (photosynthesis and respiration) for the corals Pocillipora damicornis and Porites cylindrica; in doing so we present a novel dataset examining the interactive role of temperature, light and pCO2 on the physiology of P. cylindrica.

In fine-blanking process, metallographic inspection shows that highly elongated and densely packed grains extend along the shear direction within a narrow large deformation region, meanwhile micro-cracks initiate and grow up. By taking the effect of shear loading into account, the recent modified GTN model proposed in 2014 is implemented and validated. The shear damage model combines the damage mechanics concept with the porous plasticity model and is applied to simulate fine-blanking process to verify its accuracy in predicting material damage and tearing fracture. The formation and propagation of shear band in fine-blanking process are studied. Both numerical results and experimental observations reveals that the effect of shear damage plays a significant role in inducing tearing, which eventually leads to fracture failure in the fine-blanking process.

Using ab initio molecular dynamics simulations, we show that oxygen (O) impurities have a noticeable influence on the glass-formation ability (GFA) in Zr2Cu alloy. Cu-centered icosahedral clusters and Zr-centered Kasper polyhedra are the dominate short-range orders in undercooled Zr2Cu liquid which are most likely to be responsible for the glass formation in Zr2Cu systems. When O is introduced, a Zr octahedron is formed around the O impurity. Most of the Zr atoms in the octahedron also serve as the bridging atoms for cross-linked Kasper polyhedral network, resulting in an O-centered medium range order (MRO) structure. Meanwhile, Cu atoms are moved away from the first shell of O-centered octahedral clusters. With 1 at. % O impurities, the fractions of Zr-centered clusters are less affected, while the increase of ideal icosahedral order and decrease of distorted icosahedral order lead to a more stable atomic structure. This result suggests that a low concentration of O impurities would improve the GFA in Zr2Cu alloy. However, when ∼5 at. % O impurities are included, the ideal icosahedral clusters and Zr-centered Kasper polyhedra are seriously suppressed by the formation of O-centered MRO, which can lead to deterioration of GFA. Our analyses provide useful insight into glass formation behavior in O-doped metallic alloy systems.

The purpose of this study was to compare iterative metal artifact reduction (iMAR), a new single-energy metal artifact reduction technique, with filtered back projection (FBP) in terms of attenuation values, qualitative image quality, and streak artifacts near shoulder and hip arthroplasties and observer ability with these techniques to detect pathologic lesions near an arthroplasty in a phantom model.Preoperative and postoperative CT scans of 40 shoulder and 21 hip arthroplasties were reviewed. All postoperative scans were obtained using the same technique (140 kVp, 300 quality reference mAs, 128 × 0.6 mm detector collimation) on one of three CT scanners and reconstructed with FBP and iMAR. The attenuation differences in bones and soft tissues between preoperative and postoperative scans at the same location were compared; image quality and streak artifact for both reconstructions were qualitatively graded by two blinded readers. Observer ability and confidence to detect lesions near an arthroplasty in a phantom model were graded.For both readers, iMAR had more accurate attenuation values (p0.001), qualitatively better image quality (p0.001), and less streak artifact (p0.001) in all locations near arthroplasties compared with FBP. Both readers detected more lesions (p ≤ 0.04) with higher confidence (p ≤ 0.01) with iMAR than with FBP in the phantom model.The iMAR technique provided more accurate attenuation values, better image quality, and less streak artifact near hip and shoulder arthroplasties than FBP; iMAR also increased observer ability and confidence to detect pathologic lesions near arthroplasties in a phantom model.

In this study, a combined experimental-numerical investigation on the failure of AZ31 Mg alloy sheet in the warm stamping process was carried out based on modified GTN damage model which integrated Yld2000 anisotropic yield criterion. The constitutive equations of material were implemented into a VUMAT subroutine for solver ABAQUS/Explicit and applied to the formability analysis of mobile phone shell. The morphology near the crack area was observed using SEM, and the anisotropic damage evolution at various temperatures was simulated. The distributions of plastic strain, damage evolution, thickness, and fracture initiation obtained from FE simulation were analyzed. The corresponding forming limit diagrams were worked out, and the comparison with the experimental data showed a good agreement.

The objective of this paper is to propose a measuring method based on the spray momentum flux measurement of each nozzle hole that could be used to determine the transient discharge coefficient of each nozzle hole of a multi-hole diesel injector. For this purpose, a measurement system for the transient discharge coefficient of each nozzle hole was established utilizing a conventional injection system of pump-line-nozzle and a dedicated constructed experimental rig. By measuring the spray momentum flux of each nozzle hole of the multi-hole fuel injector and injection pressure of the pump-pipe-injector fuel delivery system, the discharge coefficient of each nozzle hole was obtained, and analyzed throughout the injection duration and with different injection pump speeds and cycle fuel injection quantities. The results show that the transient discharge coefficient of each nozzle hole changes constantly, meanwhile, the variations of the transient discharge coefficient of the nozzle holes were similar. However, the discharge coefficient of the nozzle holes were not uniform at the same operating condition and that of the No.5 was apparently lower than that of the others. With increasing cam speed, the fluctuations of the discharge coefficients were variably stable at the maximum needle position.The fluctuations of the discharge coefficients of the nozzle holes were higher for the smaller cycle fuel injection quantity, but as the fluctuation gradually became smaller, the mean discharge coefficient of each nozzle hole increased slightly with increasing cycle fuel injection quantity.

Atmospheric exposure tests were conducted on pure copper exposed to the atmosphere for a four-year period in Turpan, China, a typical hot and dry environment. The experiments included weight-loss tests, morphology observations, composition analyses, and electrochemical techniques. The results indicated that the annual corrosion rate of pure copper was approximately 2.24 g/m2/year, and an uneven distribution of corrosion products was observed by scanning electron microscopy. This was attributed to the dehydration process that occurred during wet-dry and cold-hot cycles. The corrosion products mainly comprised cuprite (Cu2O) and atacamite (Cu2Cl(OH)3). Electrochemical measurements showed that deposits on copper improved its resistance to corrosion, but the protectiveness decreased with increasing temperature.

The first goal of this study was to investigate the accuracy of the displayed reference plane air kerma (Ka,r) or air kerma‐area product (Pk,a) over a broad spectrum of X‐ray beam qualities on clinically used interventional fluoroscopes incorporating air kerma‐area product meters (KAP meters) to measure X‐ray output. The second goal was to investigate the accuracy of a correction coefficient (CC) determined at a single beam quality and applied to the measured Ka,r over a broad spectrum of beam qualities. Eleven state‐of‐the‐art interventional fluoroscopes were evaluated, consisting of eight Siemens Artis zee and Artis Q systems and three Philips Allura FD systems. A separate calibrated 60 cc ionization chamber (external chamber) was used to determine the accuracy of the KAP meter over a broad range of clinically used beam qualities. For typical adult beam qualities, applying a single CC determined at 100 kVp with copper (Cu) in the beam resulted in a deviation of

The vibrational properties, electronic structures and optical properties of novel carbon allotropes, such as monolayer penta-graphene (PG), double-layer PG and T12-carbon, were studied by first-principles calculations. Results of phonon calculations demonstrate that these exotic carbon allotropes are dynamically stable. The bulk T12 phase is an indirect-gap semiconductor having a quasiparticle (QP) bandgap of ∼5.19 eV. When the bulk material transforms to a two-dimensional (2D) phase, the monolayer and double-layer PG become quasi-direct gap semiconductors with smaller QP bandgaps of ∼4.48 eV and ∼3.67 eV, respectively. Furthermore, the partial charge density analysis indicates that the 2D phases retain part of the electronic characteristics of the T12 phase. The linear photon energy-dependent dielectric functions and related optical properties including refractive index, extinction coefficient, absorption spectrum, reflectivity, and energy-loss spectrum were also computed and discussed. Additionally, the chemical stability of monolayer PG and the electronic and optical properties of double-side hydrogenated monolayer PG were also investigated. The results obtained from our calculations are beneficial to practical applications of these exotic carbon allotropes in optoelectronics and electronics.

Considering the effect of shear loading, an original GTN damage model is extended by combining the damage mechanics concept and the porous plasticity model. The extended model in terms of various stress triaxiality was deduced in detail. The model is extended by coupling two damage parameters into the yield function. The implementation is achieved by the development of the user material subroutine. Internal damage evolution was observed by scanning electron microscopy (SEM). Parameters were determined from experimental data and previous studies. The damage model was applied to in-situ tensile tests to compare its predictability in various specimens. The obtained numerical results were in good agreement with experimental results, showing better ductile fracture predictions.

Parvalbumin (PV)-positive interneurons in the hippocampus play a critical role in animal memory, such as spatial working memory. However, how PV-positive interneurons in the subregions of the hippocampus affect animal behaviors remains poorly defined. Here, we achieved specific and reversible activation of PV-positive interneurons using designer receptors exclusively activated by designer drugs (DREADD) technology. Inducible DREADD expression was demonstrated in vitro in cultured neurons, in which co-transfection of the hM3D-Gq-mCherry vector with a Cre plasmid resulted in a cellular response to hM3Dq ligand clozapine-N-oxide (CNO) stimulation. In addition, the dentate gyrus (DG) of PV-Cre mice received bilateral injection of control lentivirus or lentivirus expressing double floxed hM3D-Gq-mCherry. Selective activation of PV-positive interneurons in the DG did not affect locomotor activity or depression-related behavior in mice. Interestingly, stimulation of PV-positive interneurons induced an anxiolytic effect. Activation of PV-positive interneurons appears to impair social interaction to novelty, but has no effect on social motivation. However, this defect is likely due to the anxiolytic effect as the exploratory behavior of mice expressing hM3D-Gq is significantly increased. Mice expressing hM3D-Gq did not affect novel object recognition. Activation of PV-positive interneurons in the DG maintains intact cued and contextual fear memory but facilitates fear extinction. Collectively, our results demonstrated that proper control of PV interneurons activity in the DG is critical for regulation of the anxiety, social interaction and fear extinction. These results improve our fundamental understanding of the physiological role of PV-positive interneurons in the hippocampus.

Modern fluoroscopes used for image‐based guidance in interventional procedures are complex X‐ray machines, with advanced image acquisition and processing systems capable of automatically controlling numerous parameters based on defined protocol settings. This study evaluated and compared approaches to technique factor modulation and air kerma rates in response to simulated patient thickness variations for four state‐of‐the‐art and one previous‐generation interventional fluoroscopes. A polymethyl methacrylate (PMMA) phantom was used as a tissue surrogate for the purposes of determining fluoroscopic reference plane air kerma rates, kVp, mA, and variable copper filter thickness over a wide range of simulated tissue thicknesses. Data were acquired for each fluoroscopic and acquisition dose curve within each vendor's default abdomen or body imaging protocol. The data obtained indicated vendor‐ and model‐specific variations in the approach to technique factor modulation and reference plane air kerma rates across a range of tissue thicknesses. However, in the imaging protocol evaluated, all of the state‐of‐the‐art systems had relatively low air kerma rates in the fluoroscopic low‐dose imaging mode as compared to the previous‐generation unit. Each of the newest‐generation systems also employ Cu filtration within the selected protocol in the acquisition mode of imaging; this is a substantial benefit, reducing the skin entrance dose to the patient in the highest dose‐rate mode of fluoroscope operation. Some vendors have also enhanced the radiation output capabilities of their fluoroscopes which, under specific conditions, may be beneficial; however, these increased output capabilities also have the potential to lead to unnecessarily high dose rates. Understanding how fluoroscopic technique factors are modulated provides insight into the vendor‐specific image acquisition approach and may provide opportunities to optimize the imaging protocols for clinical practice. PACS number: 87.59.C‐

Although channelized urban streams provide aesthetic and economic value, they reduce biodiversity and alter the habitats of aquatic organisms. Spur dikes not only prevent the erosion of riverbanks, but also generally improve aquatic habitats. River 2D is widely used to analyze the aquatic habitats. However, the model often faces a challenge of lacking sediment and riverbed evolution module, which is difficult to predict the change of aquatic habitats. In this study, a depth-averaged habitat model, which couples a two-dimensional water-sediment shallow water model with an Instream Flow Incremental Methodology (IFIM), was provided to evaluate the impact of spur dikes on the improvement of aquatic habitats in the Jinjiang Stream in Chengdu, China. The potential value of aquatic habitats was quantitatively evaluated by a weighted useable area (WUA). Under different spur dike scenarios, the WUA is greater than under natural conditions, that is, the construction of spur dikes is beneficial for improving the habitat of aquatic organisms in urban rivers. In addition, further analysis from the simulation results shows that the three-spur dike scenario with a flow of 40 m³/s represents the best layout of spur dikes. Our study indicates that adjusting the spur dike layout is an effective instrument to enhance aquatic habitats, and can provide a certain reference for water ecological restoration and river management.

In this work, the kinetics of destruction of boron carbide subjected to mechanical loads was studied based on molecular dynamics method using the reactive force field approach to describe the inter-atomic interactions. In simulations, kinetics of bonds for the configurations (B12)(CCC) and (B11Cp)(CBC) and the behavior of stress tensor and temperature were monitored. The results of simulations indicate that the structural collapse in boron carbide under uniaxial loads is associated in first place with breaking the intra-icosahedral bonds, while the inter-icosahedral bonds are affected with some delay and much less. In a number of runs, the irreversibility of structural changes occurring at structural breakdown is demonstrated.

Since the coordinated development plan of Beijing-Tianjin-Hebei region was put forward, environmental protection and pollution control have become the primary breakthrough of coordinated development. The ecological environment problem in Beijing- Tianjin-Hebei region has been the bottleneck factor restricting the integrated development. It is of great significance for environmental protection and economic development to establish a coordinated assessment mechanism for ecological environment quality in Beijing-Tianjin- Hebei region. This study analyzed the progress and effectiveness of the assessment of ecological environment quality in Beijing-Tianjin-Hebei region, analyzed the problems and challenges in the assessment of ecological environment in Beijing-Tianjin-Hebei region, and put forward some suggestions on the establishment of the mechanism of joint environmental prevention and control under the coordinated development of Beijing-Tianjin-Hebei region.

The CRISPR/Cas9 system is a powerful tool for the treatment of infectious diseases. In our previous study, we knocked out the Bombyx mori nucleopolyhedrovirus (BmNPV) key genes and BmNPV-dependent host factor to generate transgenic antiviral strains. To further expand the range of target genes for BmNPV and more effectively prevent and control pathogenic infections, we performed gene editing and antiviral analysis by constructing a target-directed baculovirus early transcriptional activator immediate early-0 (ie-0) and 2 (ie-2) transgenic silkworm line. We hybridized it with Cas9 transgenic line to produce a double-positive transgenic Cas9(+)/sgIE0-sgIE2(+) line that could activate the CRISPR gene editing system. We first demonstrated that the system is capable of efficiently editing target genes and resulting in fragment deletions in the BmNPV genome. Survival rate of the transgenic Cas9(+)/sgIE0-sgIE2(+) line reached 65% after inoculation with 1 × 10

Physical review letters 121(5), 051103 (2018). doi:10.1103/PhysRevLett.121.051103, Published by APS, College Park, Md.

Parasitic wasps rely on olfaction to locate their hosts in complex chemical environments. Odorant receptors (ORs) function together with well-conserved odorant coreceptors (ORcos) to determine the sensitivity and specificity of olfactory reception. Campoletis chlorideae (Hymenoptera: Ichneunmonidae) is a solitary larval endoparasitoid of the cotton bollworm, Helicoverpa armigera, and some other noctuid species. To understand the molecular basis of C. chlorideae's olfactory reception, we sequenced the transcriptome of adult male and female heads (including antennae) and identified 211 OR transcripts, with 95 being putatively full length. The tissue expression profiles, as assessed by reverse-transcription PCR, showed that seven ORs were expressed only or more highly in female antennae. Their functions were analysed using the Xenopu slaevis oocyte expression system and two-electrode voltage-clamp recordings. CchlOR62 was tuned to cis-jasmone, which was attractive to female C. chlorideae adults and H. armigera larvae in the subsequent behavioural assays. Further bioassays using caged plants showed that the parasitism rate of H. armigera larvae by C. chlorideae on cis-jasmone-treated tobacco plants was higher than on the control plants. Thus, cis-jasmone appears to be an important infochemical involved in the interactions of plants, H. armigera and C. chlorideae, and CchlOR62 mediates the attractiveness of cis-jasmone to C. chlorideae.

The $\mathrm{H}_{\infty}$ loop shaping method based on coprime factorization is widely used in the design of flexible systems. In the paper $\mathrm{H}_{\infty}$ loop shaping design for lightly damped system shows coprime factor perturbations can be used to represent parameter perturbation in the robust design, but it also reduces the robustness of the design. So coprime factor perturbation is not effective like recognized, its use is limited. The paper detailed analysis of coprime factor perturbation, with a lightly damped system parameter perturbation designed to illustrate the robustness of prime factorization problem occurs in use.

Phase-change memory is one of the most promising candidates for future memory technologies. However, most of the phase-change memories are based on chalcogenides, while other families of materials for this purpose remain insufficiently studied. In this work, we investigate the optical properties and microstructure of Ga16Sb84 by an in-situ ellipsometer and X-ray diffraction. Our experimental results reveal that the Ga16Sb84 films exhibit a relatively high crystallization temperature of ~250 °C, excelling in long data retention. In addition, a large optical contrast exists between the amorphous and crystalline states, which may make it suitable for use in optical discs. Molecular dynamics simulations indicate that a unique local structure order in the amorphous and crystalline phases is responsible for the optical properties observed in the experiment. The similarity found in the short-range orders of the amorphous and crystalline phases is beneficial to better understanding the fast phase transition of phase-change memory.

Background Systemic lupus erythematosus (SLE) is a chronic multi-system autoimmune disease impacting the physical wellbeing and health related quality of life (HRQOL) of patients1. Fatigue occurs in up to 90% of SLE patients and affects their HRQOL2. The purpose of this pilot study is to determine the effect of milnacipran, a norepinephrine and serotonin reuptake inhibitor used to treat fibromyalgia, on fatigue in clinically stable SLE patients with widespread pain (WSP). To date, no clinical trials have demonstrated efficacy for the primary treatment of fatigue and WSP in adult SLE patients. Objectives The objective is to determine the effect of milnacipran on fatigue in a clinically stable lupus cohort. Methods SLE patients, 18 years and older, with fatigue, WSP and on more than 4 weeks of stable therapy were recruited for a 15 week prospective, double-blind, placebo-controlled study. Patients were randomised at a 1:1 ratio to receive 14 weeks of milnacipran 50–100 mg twice a day or placebo. Disease activity was measured by the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Measurements of fatigue, pain and a patient’s general impression of change from baseline were assessed at baseline and week 14 using the Fatigue Severity Scale(FSS), the Short-Form McGill Pain Questionnaire (SF-MPQ)3, and the Patient’s Global Impression of Change (PGIC) respectively. Results A total of 14 patients were included in the final analysis with seven patients in each group. Upon entry and throughout this study, both groups had low disease activity (mean SLEDAI Conclusions Although results were not significantly different in this pilot study, improvement in fatigue and the patient’s impression of global change appeared to be greater in the intervention group than the placebo group even though lupus activity remained low in both groups and the difference in pain between the two groups were nearly identical. Therefore, milnacipran may improve fatigue independently of disease activity and pain in lupus patients. Future randomised controlled trials of the drugs effect with larger cohorts are needed to confirm these findings. References [1] Kuriya B, et al. Arthritis and Rheum. 2008;59(2):181–5. [2] Abina-Zubieta JA, etal. Arthritis and Rheum. 2007;56(8): 1348–1357. [3] Burckhardt CS, Jones KD. Arthritis and Rheum. 2003; 49(5S): S96-S104. Acknowledgements Kendall Boyd, PhD, Loma Linda University Allergan/Forest Laboratories Disclosure of Interest E. Katsaros Grant/research support from: Allergan/Forest Laboratories, F. Dong: None declared, I. Moldovan: None declared

Crystalline Sb2Te3 is widely studied due to its important applications in memory materials and topological insulators. The liquid and amorphous structures of this compound as well as the dynamics upon quenching, however, are yet to be fully understood. In this work, we have systematically studied the dynamical properties and local structure of Sb2Te3 at different temperatures using ab initio molecular dynamics simulations. The calculated structure factors agree well with the experimental results. The atomic number density and mean-squared displacement as a function of temperature clearly indicate three states as the temperature decreases, namely, melt, undercooled liquid and glass state, respectively. By analyzing the chemical environments and bond-angle distribution functions, we demonstrate that the most probable short-range motifs in the Sb2Te3 system are defective octahedrons, and they are connected with each other via four-fold rings. This interesting structural feature may be responsible for the high fragility and easy phase transition upon glass forming that is applied in memory devices.

Phase-change memory is one of the most promising candidates for future memory technologies. However, most of the phase-change memories are based on chalcogenides, while other families of materials for this purpose remain insufficiently studied. In this work, we investigate the optical properties and microstructure of Ga16Sb84 by an in-situ ellipsometer and X-ray diffraction. Our experimental results reveal that the Ga16Sb84 films exhibit a relatively high crystallization temperature of ~250 °C, excelling in long data retention. In addition, a large optical contrast exists between the amorphous and crystalline states, which may make it suitable for use in optical discs. Molecular dynamics simulations indicate that a unique local structure order in the amorphous and crystalline phases is responsible for the optical properties observed in the experiment. The similarity found in the short-range orders of the amorphous and crystalline phases is beneficial to better understanding the fast phase transition of phase-change memory.

Objective: To determine if there are differences in short-term weight loss and long-term weight maintenance success by age or gender. Methods: Patients were enrolled in a Midwestern weight loss clinic. The primary outcome measures were short-term weight loss success (achieving ≥ 10% of the initial body weight loss (IBWL) at three months) and long-term weight maintenance success (maintaining ≥ 10% IBWL at one year). Results: Patients 18 – 45 years were more likely to achieve short-term weight loss success compared to those in the two other age categories (45-64 and ≥ 65 years). However, age was not a significant predictor for long-term weight maintenance success. Females had decreased odds (OR=0.47, 95% CI 0.38, 0.59) of achieving short-term weight loss success, but had increased odds (OR=1.94, 95% CI 1.02, 3.67) of achieving long-term weight maintenance success. Discussion: Age and Gender effect were different for short-term weight loss and long-term weight maintenance success.

This study was designed to evaluate the physiological and cytological responses in liver of GIFT tilapia (Oreochromis niloticus) to acute copper exposure. Fish were exposed to three Cu treatments at the following concentrations: 0 (control), 1.96 mg/L and 3.92 mg/L, and liver samples were collected after 96h of exposure. Observation of oil red O staining showed that acute copper exposure increased lipid accumulation in liver, which may due to changes of hepatic enzyme activities (malic enzyme, lipoprotein lipase, hepatic lipase, fatty acid synthetase, carnitine palmitoyltransferases l) and lesions of some organelles such as mitochondria and swollen rough endoplasmic reticulum of hepatocytes. This study indicated that acute copper exposure induced hepatic lipid metabolic disturbances and damaged hepatic organelle in GIFT tilapia.

This study was conducted to evaluate the effects of dietary protein levels on growth performance and digestive enzyme activities of juvenile hybrid culter (Culter alburnus ♀× Ancherythroculter nigrocauda ♂). Five solipidic experimental diets were formulated to contain graded levels of protein ranging from 29.54-48.98%. These were fed to triplicate groups of fish (11.44 ± 0.7 g/fish) for 8 weeks. Results from the feeding trial indicated that growth performance, body composition, and digestive enzyme activities of the fish were significantly different (P

In this study, a grain boundary model with three-dimensional (3D) cohesive elements for analyzing the intergranular stress corrosion cracking (IGSCC) on the crystal level in polycrystalline materials is presented. The objectives are to characterize the grain boundary microstructure and the fracture mechanism of IGSCC in AZ31 Mg alloy. In order to investigate the development of the microcrack and its effects on macrocrack evolution, a novel model of IGSCC propagation has been developed, in which the 3D Voronoi tessellations geometry is employed to model polycrystalline grain structures. And the 3D cohesive elements with zero constitutive thickness are directly inserted on the faces of two adjacent grains. The effect of the embrittlement due to the presence of hydrogen has also been included in the cohesive model. To validate the model, an IGSCC process of AZ31 Mg alloy in NaCl solution has been simulated, with the influence of hydrogen concentration being taken into account. It is found that damage develops at the triple lines between the grains and the combinations of grains can lead to high stresses at the grains boundary, especially those that are normal to the direction of the applied strain. In this paper, the effects of damage due to hydrogen and the grain sizes in microstructure are considered. The simulation results have a good consistency with the experimental phenomenon.

Atmospheric corrosion behavior of 7A04 aluminum alloy exposed to a tropical marine environment for 4 years was investigated by weight loss test, morphology observation, and electrochemical impendence spectroscopy (EIS). The results showed that the weight loss of 7A04 alloy in the log-log coordinates can be approximately fitted with two liner segments, in which the slope value of the second segment is significantly lower than that of the first segment. This was mainly attributed to the protectiveness of the corrosion product layer formed on the specimen exposed for 12 and 24 months, which was further confirmed by the EIS results. Corrosion rate presented a significant fluctuation during the exposure test which is due to the deterioration effect caused by chloride ions and time of wetness and the stabilization process of the corrosion product layer. Intergranular corrosion occurred on the 7A04 alloy and then transformed into exfoliation corrosion because of the synergetic effect of the hydrogen-assisted crack initiation and the wedge effect-induced matrix delamination.

The genetic basis of stomatal conductance (g s), net photosynthetic rate (P N), and transpiration rate (E) was explored by using a wheat doubled haploid population from a cross of Hanxuan10 and Lumai 14. The above three traits were evaluated in wheat flag leaves at 10, 20, 30 days after anthesis under drought stress (DS) and well-watered (WW), and quantitative trait loci (QTL) were analyzed. Expression of the traits during the grain filling stage showed downward trends under both conditions, but expression of three phenotypes were stronger under WW than those under DS. Extremely significant positive correlations were established among the traits at all growth stages under both conditions. A total of 18 additive QTLs for those traits were identified on 10 chromosomes. Among them, two batches of nine additive QTLs were associated with the target traits under DS and WW, respectively. Two additive QTLs for g s and E, two for g s and P N, six for g s, P N, and E clustered at the same or near the region (colocation) of chromosomes 4A, 2B, and 7B, respectively. This provided genetic basis for close phenotype correlations among g s, P N, and E. Furthermore, QTLs for g s, P N, and E near Xgwm577 and Xgwm611 located on 7B chromosome were linked to previously reported QTLs regulating a SPAD value and the chlorophyll a/b ratio under dark-induced condition. This finding indicated that these QTLs on 7B chromosome might be involved in the process of wheat leaf senescence.

The structures and dynamics of liquid Ag74Ge26 alloy at different temperatures were investigated by high-energy X-ray diffraction and ab initio molecular dynamics simulation. The calculated structure factors agree well with the experimental data. Local atomic structure orders have been characterized by angular distribution functions, Honeycutt-Andersen index, Voronoi tessellation and the atomic cluster alignment. We reveal that (i) , , , and polyhedral dominate in the undercooled Ag74Ge26 liquid. (ii) The icosahedral-like short-range order is enhanced as the temperature decreases while , , , and polyhedral become the major short-range orders at low temperature. (iii) The medium-range order which was formed for amorphous phase at ambient temperature persists in the undercooled liquid. In addition, it is found that the diffusion constant of Ag is lower than that of Ge over the studied temperature range. Our findings elucidate that highly dominated short-range order associated with nearest-neighbors shell could empower the development of medium-range order and the formation of metallic glasses. (C) 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

This paper presents an experimental research on timber columns with externally bonded fibre reinforced polymer sheets, which consist of aramid fibre reinforced polymer, carbon fibre reinforced polymer and basalt fibre reinforced polymer. This is to provide a strengthening solution to upgrade the structural behaviour and load carrying capacities of such columns under the influence of fractured wood texture. In total, 14 columns were constructed and tested, consisting of 8 circular timber columns and 6 square ones. Besides, three columns of such two section types with knag were reinforced by wrapping of carbon fibre reinforced polymer sheets and tested. The failure mode was analysed, as well as the fracture surface. Externally bonded fibre reinforced polymer sheets were found to be very effective in upgrading the compressive strength of the columns strengthened. The enhancement on load carrying capacities by fibre reinforced polymer reinforcement is in the range of 69–103% for the specimens with a c...

Based on the experimental tests of timber square columns strengthened by fibre-reinforced polymer sheets under axial compression, the failure modes, load carrying capacity, loading–strain curves, ductile and stiffness factors were examined. The results showed that in comparison with specimens without FRP reinforcement, the axial load carrying capacity, the peak of compression strain and stiffness of specimens with fibre-reinforced polymer reinforcement were all improved. The ultimate load carrying capacity of specimens with fibre-reinforced polymer reinforcement was improved by 68·9–100·2%. However, the ultimate displacement was decreased by 46·1–56·9%, and the lowest displacement was found in the specimens strengthened by two layers of basalt fibre-reinforced polymer. Meanwhile, specimens reinforced by two layer of carbon fibre-reinforced polymer and aramid fibre-reinforced polymer sheets showed a higher level of ultimate displacement and stiffness than specimens with basalt fibre-reinforced polymer rein...

SummaryCytoplasmic male sterility (CMS) is one of the most important systems for the production of F1 hybrid seed. Here, we obtained two sequence-characterised amplified region (SCAR) markers that could distinguish between male-sterile (S) and normal (N) types of cytoplasm in bunching onion (Allium fistulosum L.). A 327-bp S band (designated S327) was amplified in the male sterile line 980238A and a 1,412-bp N band (designated N1412) was amplified in its maintainer line 980238B. Both SCAR markers were verified in five male-sterile lines and their five maintainer lines, in four paternal lines and their self-crossed progenies, and in four cross combinations (one male-sterile line as the female parent and the four male-fertile paternal lines as the male parents). All the results agreed with their corresponding cytoplasmic type (S or N). Our findings suggest that the cytoplasm of A. fistulosum can be identified as male-sterile or normal using these two SCAR markers.These findings are expected to make a signif...