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By solving the continuity equation of excitons under steady excitation, a theoretical model for the excitonic luminescence of semiconductors was developed taking into account the exciton diffusion and surface recombination. The theoretical model was used to analyze the photoluminescence (PL) spectra of ZnO obtained from the bulk single-crystal samples with and without surface passivation, showing that the nonradiative recombination on the surface is an important channel of losing excitons, thus substantially reducing the PL quantum efficiency of excitons at room temperature. In addition, the surface recombination was found to have impacts on the fine structure of excitonic luminescence at low temperature. Using the theoretical model, the diffusion length of excitons at room temperature was estimated and found to be different from sample to sample, strongly depending on the sample processing. The theoretical model was demonstrated to be capable of accurately fitting the temperature-dependent PL intensity of passivated samples and showed that the exciton diffusion has significant impacts on the dynamics of excitonic luminescence at high temperature. [ABSTRACT FROM AUTHOR]

The protective performance of a three-layer explosive welded composite plate consisting of steel and aluminum plates is studied in ballistic experiments and numerical simulations. The mechanism of target plate failure under the impact of spherical fragments is investigated. [ABSTRACT FROM AUTHOR]

Background: Long-term survival outcomes of trimodal therapy (TMT; chemoradiation plus surgery) and bimodal therapy (BMT; chemoradiation) have seldom been analysed. In a selective-surgery paradigm, the benefit of TMT in patients with a complete clinical response is controversial. Factors associated with survival in patients with a clinical complete response to chemoradiation were evaluated. Methods: Patients with stage II-III oesophageal squamous cell carcinoma treated with TMT or BMT from 2002 to 2017 were evaluated. The BMT group consisted of patients who were otherwise eligible for surgery but underwent chemoradiation alone followed by observation. This group included patients who later had salvage oesophagectomy. Survival was evaluated and compared between TMT and BMT groups. Elastic net regularization was performed to select co-variables for Cox multivariable survival analysis in patients with a clinical complete response. Results: Of 143 patients, 60 (41.9 per cent) underwent TMT and 83 (58.0 per cent) BMT. Patients who underwent TMT had longermedian overall survival than those who had BMT (77 versus 33months; P=0.019). For patients with a clinical complete response, TMT achieved longer median overall survival than BMT (123 versus 55months; P=0.04). BMT had a high locoregional recurrence rate (48 versus 6 per cent; P<0.001); 26 of 29 patients with locoregional recurrence in the BMT groupunderwent salvage resection. Coxmultivariable analysis demonstrated that upper-mid oesophageal tumour location (hazard ratio (HR) 2.04; P=0.024) and tumour length (HR 1.18; P=0.046) were associated with worse survival. Although TMT was not associated with survival, it was a predictor of reduced recurrence (HR 0.28; P=0.028). The maximumstandardized uptake value after chemoradiation also predicted recurrence (HR 1.33; P<0.001). Conclusion: In patients who achieve a clinical complete response, TMT reduces locoregional recurrence but may not prolong survival. The differences in survival outcomes may be due to patient selection; therefore, a selective-surgery strategy in oesophageal squamous cell carcinoma is a reasonable approach. [ABSTRACT FROM AUTHOR]

Under ultraviolet (UV) excitation with photon energy larger than 4.5 eV, a charge-state conversion from negatively to neutrally charged nitrogen-vacancy (NV− to NV0) centers in diamond samples is realized. The UV-induced charge-state conversion is found to strongly depend on the N concentration in the sample and the irradiation fluence of the electron beam. For the samples with high N concentrations, low-fluence (2.5 × 1017 cm−2) 10-MeV electron beam irradiation usually leads to UV-induced charge-state conversion efficiency higher than that of the samples irradiated with high fluences (≥2.5 × 1018 cm−2). For the samples with a few ppm N, however, the charge-state conversion efficiency is relatively low in the cases of irradiation fluences in this work. Meanwhile, UV-induced NV0 luminescence exhibits temperature dependence different from that of visible-light excited NV0 or NV− centers; that is, the photoluminescence intensity does not reach saturation at temperatures lower than 135 K but decreases with the decrease in temperature. Based on the photoluminescence excitation spectra of NV0 centers in the UV region, the UV-induced charge-state conversion is suggested to involve free-hole generation, diffusion, and the capture by ground-state NV− centers. [ABSTRACT FROM AUTHOR]

The effects of surface conditions on photo-induced-carrier (PIC) diffusion are studied by solving one-dimensional continuity equation. Using various forms of ZnO samples with different surface conditions, the PICs lost at sample surface are substantiated to have important contributions to the visible luminescence. For unpassivated ZnO nanorods and single-crystal samples that undergo a high-temperature annealing in air, the visible luminescence originating from the PICs diffused to the surface is estimated more than 99.8 % and 70 % at room temperature, respectively, and more than 99.99 % and 97 % at low temperature. The structureless luminescence caused by PICs, such as the green, yellow, and orange luminescence bands are well fitted under the framework of tail-state luminescence, while the structured green band is suggested to be in association with a specific type of surface states formed during high-temperature annealing in oxidizing atmosphere and can be fitted with Huang-Rhys model by taking into account tail-state luminescence. [ABSTRACT FROM AUTHOR]

Key message: The genetic determinism of prickle in rose is complex, with a major locus on LG3 that controls the absence/presence of prickles on the rose stem. Rose is one of the major ornamental plants. The selection of glabrous cultivars is an important breeding target but remains a difficult task due to our limited genetic knowledge. Our objective was to understand the genetic and molecular determinism of prickles. Using a segregating diploid rose F1 population, we detected two types of prickles (glandular and non-glandular) in the progeny. We scored the number of non-glandular prickles on the floral and main stems for three years. We performed QTL analysis and detected four prickle loci on LG1, 3, 4 and 6. We determined the credible interval on the reference genome. The QTL on LG3 is a major locus that controls the presence of prickles, and three QTLs (LG3, 4 and 1) may be responsible for prickle density. We further revealed that glabrous hybrids are caused by the combination of the two recessive alleles from both parents. In order to test whether rose prickles could originate from a 'trichome-like structure,' we used a candidate approach to characterize rose gene homologues known in Arabidopsis, involved in trichome initiation. Four of these homologues were located within the overlapping credible interval of the detected QTLs. Transcript accumulation analysis weakly supports the involvement of trichome homologous genes, in the molecular control of prickle initiation. Our studies provide strong evidence for a complex genetic determinism of stem prickle and could help to establish guidelines for glabrous rose breeding. New insights into the relationship between prickles and trichomes constitute valuable information for reverse genetic research on prickles. [ABSTRACT FROM AUTHOR]

To study the explosive characteristics of improvised explosive devices (IEDs), the damage mode of cylindrical IEDs and the formation mechanism of natural fragments under blast loading are investigated by using the ANSYS/AUTODYN 3D finite element code with Mott's stochastic failure model, as well as experiments of the hydraulic burst test and explosion test. The influence of the explosive charge amount and its position is also discussed. The main damage mode of the pressure container is the shearing damage, which is obviously affected by the explosive charge amount, charge position, and its power. The ability of the instantaneous function (pressurization rate) of the self-made explosive is far smaller than that of the standard explosive. Under the action of the self-made explosive, the closer to the detonation point, the smaller the size of the fragments formed. [ABSTRACT FROM AUTHOR]

The present study was carried out to determine the effect of chilling stress on mung bean [Vigna radiata (L.) Wilczek], and the possible mediatory role of applied 5-aminolevulinic acid (ALA) on osmotic adjustment and antioxidant system. The increased accumulation of superoxide radical, hydrogen peroxide, and malondialdehyde during chilling stress indicates an enhanced oxidative stress. The chilling stress induced an enhancement of reduced or oxidized glutathione and ascorbic acid, and improvement of superoxide dismutase (SOD), peroxidase (POD), glutathione reductase (GR), and ascorbate peroxidase (APX) activities, but the activity of catalase (CAT) declined. Exogenous ALA enhanced the content of glutathione and ascorbic acid and elevated the antioxidant enzyme activities (POD, SOD, GR, and APX), which improved reactive oxygen species scavenging. In addition, an increased content of osmoprotectants including soluble sugars, soluble proteins, and proline contributed to ROS detoxification and enzyme/protein stabilization. Thus, ALA had a positive effect in improving the chilling resistance of mung bean plants. [ABSTRACT FROM AUTHOR]

Multiphonon assisted optical emission processes of ZnO in the vicinity of excitonic luminescence were investigated using the excitation-emission maps and the photoluminescence (PL) excitation spectra recorded at different emission photon energies. Multiphonon resonant Raman scattering (RRS) was found to have the temperature dependence similar to the excitonic luminescence, but not to be influenced by the surface conditions and annealing process. The multiphonon RRS and the longitudinal optical (LO) phonon replicas of PL lines were substantiated to originate from the cascade scattering of exciton polaritons with successively emitting LO phonons. The second-order Raman processes were observed to take part in the capture of exciton polaritons by the defects, forming the neutral donor bound excitons. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify potential high-frequency mutation (HFM) genes and associated molecular mechanisms during the progression of thyroid cancer (TC). The mutation frequency of genes was investigated using datasets from The Cancer Genome Atlas (TCGA), FoundationOne, and Memorial Sloan Kettering Cancer Center-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT). Tumor mutation burden (TMB) analysis was performed on each dataset to identify the HFM genes, which served as the data inputs for the following analyses: survival, clinical factor correlation, enrichment, and HFM gene-drug interactions. Lastly, based on the HFM genes, the protein-protein interaction (PPI) network and modules were investigated, followed by pathway analysis of the modules. TMB analysis showed that among the three datasets, missense mutations were the most common mutation type; BRAF and NRAS were also common high-frequency mutations. A total of three, six, and eight HFM genes were identified in the TCGA, FoundationOne, and MSK-IMPACT datasets, respectively. PIK3CA and TP53 in MSK-IMPACT were found to be significantly correlated with TC prognosis. Moreover, BRAF and NRAS were significantly correlated with the histologic type of TC. A total of 228 gene-drug interactions were obtained from the DGIdb database. A PPI network was constructed using 58 genes, including RPS27A, followed by five module extractions. Enrichment analysis for genes in PPI and modules showed that PTEN was a common gene enriched in prostate cancer and the FoxO signaling pathway. BRAF and NRAS are novel targets for gene therapy of TC. BRAF and NRAS mutations may correlate with the histologic type of TC. PIK3CA, TP53, and RPS27A may serve as novel prognostic genes for TC. PTEN may participate in the progression of TC via prostate cancer and the FoxO signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Dental caries and periodontal diseases are the most common oral diseases among human beings. Individuals with intellectual disabilities (IDs) have poor oral health and limited access to dental care. The aim of this study was to investigate the efficacy of strategies in caries and gingivitis prevention among children and adolescents with ID. Methods: Four electronic databases (PubMed, Cochrane Library, Web of Science and Scopus) were searched from their commencement date to 17 April 2017. Randomised or non‐randomised controlled trials evaluating the efficacy of interventions in caries and gingivitis prevention were included if the participants were children and adolescents with ID. Gingival index and caries experiences were reported in the format of mean difference and standard error. Meta‐analysis was conducted if data could be pooled from two or more studies using similar outcome measurements and intervention. Results: A total of 1455 articles published in English were identified. Fourteen studies formed the basis of qualitative analysis; six studies were feasible to perform quantitative analysis. Meta‐analysis favoured fluoride to placebo in caries prevention [Z = 2.02, P < 0.05, 95% CI: −0.71 (−1.40, −0.02)], while the effectiveness of chlorhexidine remained elusive. Conclusions: Both mechanical and chemical approaches had been applied to caries and gingivitis prevention among children and adolescents with ID. Insufficient evidence supported the efficacy of chlorhexidine nor powered toothbrush, while fluoride was suggested to be an effective caries preventive strategy in fluoride‐deficient areas. More well‐designed randomised controlled trials using integration strategies are encouraged in further studies. [ABSTRACT FROM AUTHOR]

A new fine structure of red luminescence (RL) was observed in unintentionally doped ZnO at low temperature. The new RL was demonstrated to be different from the one assigned to Fe3+ center by Heitz et al and visible only under the excitation of light capable of generating excitons. The RL can be extremely enhanced at the incident frequency in resonance with the donor exciton and the intensities of some adjacent lines separated by ∼4 meV are thermally populated with the increase in temperature. The new structured RL was studied in the terms of photoluminescence (PL) and PL excitation spectra and the origin was discussed taking into account the internal transitions of transition metal elements, structure defects, and native point defects. There is a great possibility that the new structured RL arises from the excited states converted from bound excitons, for example, the excitons or the electron and hole pairs bounded by the donor and acceptor pairs (DAPs) of O and Zn vacancies, because the binding energy determined by the equation of DAP fluorescence is highly in accordance with the theoretic values reported in the literature. [ABSTRACT FROM AUTHOR]

The superior colliculus (SC) is a major site of sensorimotor integration in which sensory inputs are processed to initiate appropriate motor responses. Projections from the primary visual cortex (V1) to the SC have been shown to exert a substantial influence on visually induced behavior, including "freezing." However, it is unclear how V1 corticotectal terminals affect SC circuits to mediate these effects. To investigate this, we used anatomical and optogenetic techniques to examine the synaptic properties of V1 corticotectal terminals. Electron microscopy revealed that V1 corticotectal terminals labeled by anterograde transport primarily synapse (93%) on dendrites that do not contain gamma aminobutyric acid (GABA). This preference was confirmed using optogenetic techniques to photoactivate V1 corticotectal terminals in slices of the SC maintained in vitro. In a mouse line in which GABAergic SC interneurons express green fluorescent protein (GFP), few GFP‐labeled cells (11%) responded to activation of corticotectal terminals. In contrast, 67% of non‐GABAergic cells responded to activation of V1 corticotectal terminals. Biocytin‐labeling of recorded neurons revealed that wide‐field vertical (WFV) and non‐WFV cells were activated by V1 corticotectal inputs. However, WFV cells were activated in the most uniform manner; 85% of these cells responded with excitatory postsynaptic potentials (EPSPs) that maintained stable amplitudes when activated with light trains at 1–20 Hz. In contrast, in the majority of non‐WFV cells, the amplitude of evoked EPSPs varied across trials. Our results suggest that V1 corticotectal projections may initiate freezing behavior via uniform activation of the WFV cells, which project to the pulvinar nucleus. Electron microscopy revealed that the majority of corticotectal terminals (purple overlay) contact (arrow) small non‐GABAergic dendrites (green overlay). Excitatory postsynaptic responses (green traces) to optogenetic activation of corticotectal terminals (purple) were recorded in vitro in a variety of cell types; wide field vertical cells (green neuron) displayed the most uniform responses. [ABSTRACT FROM AUTHOR]

This paper describes an experimental study of the flame propagation mechanism for the combustible gas explosion in a closed pipe with a length of 12 m and an internal diameter of 0.125 m, which is carried out for different values of the ignition energy. The results show that an increase in the ignition energy results in greater explosive intensity, maximum peak pressure, and dynamic strain of the thin wall in the whole process. Moreover, the dynamic strain of the thin-walled pipe increases suddenly owing to arrival of a precursor shock wave and then vibrates for a long time, which is induced by the wave reflected back and forth. In addition, there is good agreement between the dynamic strain signals and pressure wave signals. These research results can provide a theoretical basis for industrial explosion accident assessments as well as explosion and shock resistance designs, which provides guidance not only for industrial safety, but also for prevention and mitigation of explosion accidents. [ABSTRACT FROM AUTHOR]

A stereomicroscope, microscopic metallograph, scanning electron microscope, and the ANSYS/LS-DYNA 3D finite-element code were employed to investigate the failure and energy absorption mechanism of two-layer steel/aluminum and three-layer steel/aluminum/steel and aluminum/steel/aluminum explosively welded composite plates impacted by spherical fragments. The effects of layer number, target order, and the combination state of interfaces on the failure and energy absorption mechanism are analyzed based on experimental and numerical results. Results showed that the effect of the combination state of interfaces on the failure mode was pronounced the most compared with other factors. The failure mechanism of the front and middle plates were shearing and plugging, and that of rear plate was ductile deformation when the tied interface failed by tension (or by shearing and plugging when the interface combination remained connected). A narrow adiabatic shear band was formed in the locally yielding plate damaged by shearing and plugging during the penetration process. The amount of energy needed to completely perforate the three-layer composite target was greater than that for a two-layer composite target with the same areal density and total thickness. The protective performance of the steel/aluminum/steel target was better than that of the aluminum/steel/aluminum target with the same areal density. [ABSTRACT FROM AUTHOR]

The problem of asymptotic stability of delay-controlled nonlinear stochastic systems with actuator failures is investigated in this paper. Such a system is formulated as a continuous-discrete hybrid system based on the random switch model of failure-prone actuator. Time delay control force is converted into delay-free one by randomly periodic characteristic of the system. Using limit theorem and stochastic averaging, an approximate formula for the largest Lyapunov exponent of the original system is then derived, from which necessary and sufficient conditions for asymptotic stability are obtained. The validity and utility of the proposed procedure are demonstrated by using a stochastically driven nonlinear two-degree system with time delay feedback and actuator failure. [ABSTRACT FROM AUTHOR]

A simple approach to preparing dopamine-modified polypropylene fibers with a controllable polydopamine amount is supplied. By the dopamine modification, the hydrophobic polypropylene fibers have been changed into hydrophilic. The hydrophilicity can be improved by increasing the amount of polydopamine, as revealed by the contact angle evolutions. The hydrophilic dopamine-modified polypropylene fibers can rapidly and effectively remove copper and lead ions in water. Moreover, the performance of removing heavy metals is prominently improved as the polydopamine amount increases. This is because the polydopamine introduction can supply many available sites for adsorbing heavy metal ions, as revealed by theoretical simulation results. These results are crucial in future engineering fiber filters towards efficiently removing heavy metal ions using dopamine-modified polypropylene fibers. [ABSTRACT FROM AUTHOR]

Seven algae strains isolated from the Great Salt Plains of Oklahoma (UTEX SP20, SP22, SP38, SP46, SP47, SP48, and SP50) were examined in this study. Biomass thermal degradation behavior of each strain was evaluated by thermogravimetric analysis. Kinetic parameters were determined using an iso-conversional approach. Algal biomass was used for bio-oil production via microwave-assisted pyrolysis, and the effects of final temperature on product yields and biooil composition were evaluated. Thermogravimetric analyses revealed that pyrolysis of algal biomass took place in three stages, with major weight loss occurring at the second stage from around 150°C to 400°C. Biomass of SP38 had the lowest average apparent activation energy (102.8 kJ mol-1), indicating that biomass of SP38 requires the least energy for pyrolysis among the seven strains. SP46 was selected out of the seven strains for microwave-assisted pyrolysis because of its high final biomass concentration and biomass productivity. As the final temperature increased from 450°C to 750°C, the bio-oil yield increased from 4.6% to 22.5% during microwave-assisted pyrolysis of biomass generated by SP46. The major compounds in the bio-oil were acids, aliphatic hydrocarbons, aromatic hydrocarbons, phenols, and organic nitrogen compounds. Microwave-assisted pyrolysis of algal biomass did not produce polycyclic aromatic hydrocarbons at temperatures higher than 450°C. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize the growth pattern, lipid content, fatty acid profile, and biomass characteristics of seven algae strains isolated from the same environment and grown in standard media under similar conditions. Proximate composition of the algae biomass was determined using a thermogravimetric analysis method. The growth profile of a selected strain (SP22) in wastewater generated during hydraulic fracturing for natural gas production (frac water) was also examined. Average biomass productivities of SP20, SP46, and SP50 were similar and significantly higher than the other strains examined in this study. Maximum biomass concentration in the culture medium (1.32 g L-1) was achieved with SP46. Green algae strains SP20 and SP22 accumulated significantly higher amounts of lipids than all the cyanobacteria investigated in this study. Saturated fatty acid contents of the algal oils varied between 32.5% and 39.9%. The highest mono- and polyunsaturated fatty acid contents were observed in SP46 and SP22, respectively. Total FAME content was highest in SP22 and second highest in SP20. Growth potential of SP22 in wastewater was also examined. This study demonstrated that SP22 can grow in frac water. Furthermore, enrichment of frac water with nutrients resulted in about 20 times more biomass productivity than that of the frac water as is, with no nutrient addition. [ABSTRACT FROM AUTHOR]

Aims To determine the concentration and molecular epidemiology of GI and GII noroviruses in sewage in China. Methods and Results Twenty-three raw sewage samples were collected in the cities of Jinan and Linyi, eastern China in 2014. GI and GII noroviruses were positive in all samples after TaqMan-based quantitative PCR. The mean concentrations of GI and GII noroviruses were 4·52 × 104 and 7·88 × 104 genome copies per litre respectively. After reverse transcription- PCR, cloning and sequencing, 16 genotypes were identified. GI.6 (69·6%), GI.2 (65·2%), GII.13 (65·2%), GII.6 (60·9%) and GII.17 (60·9%) were the most common GI and GII genotypes. A recombination event was observed in two GI.6 sequences. GII.4 sequences belonged to Sydney 2012 and Den Haag 2006b variant. Interestingly, the novel GII.17 Kawasaki308 variant was detected. Conclusions These results reveal that multiple norovirus genotypes cocirculated in the local population. The risk of acute gastroenteritis outbreak is high in the two cities due to the detection of GII.17 Kawasaki308 variant and the high concentration of norovirus in raw sewage. Significance and Impact of the Study This study demonstrates sewage surveillance can be a useful approach to monitor norovirus circulating in the population. [ABSTRACT FROM AUTHOR]

Based on the fundamental thermodynamical relations for surface phases given by Guggenheim and the rigorous discussions by Vochten, Petre, and Defay, the reversible entropy and enthalpy differences for the amphiphile molecules in between the adsorbed surface and the bulk phases of solution were derived and calculated respectively. The entropy of the amphiphile solutes at the interface is lower than that in the bulk when the adsorption is below saturation. However, when the adsorption approaches saturation the entropy difference becomes either zero or positive. These features can be reasonably explained by the adsorption-orientation effect of the amphiphile solute molecules in the interfacial adsorbed layer. [ABSTRACT FROM AUTHOR]

Aims To determine the molecular epidemiology of classic human astrovirus (HAstVs) in sewage and supplement limited clinical data in China. Methods and Results Classic HAstVs in domestic sewage in Shandong Province, eastern China in 2014 were analysed in a total of 23 sewage samples. After viral concentration, reverse transcription-PCR (RT-PCR), cloning and sequencing, all samples were positive for classic HAstVs and 115 sequences were obtained, belonging to five different genotypes (HAstV-1,-2, -3, -4 and -5). Of these, HAstV-4 (31·3%, 36/115), -5 (24·3%, 28/115) were detected with higher rates than HAstV-1 (21·7%, 25/115), followed by HAstV-2 (17·4%, 20/115) and -3 (5·2%, 6/115). High identities were observed within all genotypes in 2014. Interestingly, recombination events were identified at a high frequency (12·2%, 14/115), and variable combinations were obtained. Conclusions This study suggests that multiple HAstVs genotypes co-circulated with high prevalence in local population during surveillance period. Significance and Impact of the Study The results demonstrate that sewage analysis is a useful approach in surveillance HAstVs in the context of limited clinical data. [ABSTRACT FROM AUTHOR]

Bacterial infections increased greatly in cancer patients who accepted cytotoxic chemotherapeutics. VCS parameters of neutrophils were reported to be an indicator for acute bacterial infection accompanied by increased WBC counts. Here we explored the possibility of VCS parameters of neutrophils, monocytes and lymphocytes in indicating the local bacterial infection in cancer patients. A total of 310 cancer patients and 90 healthy controls were retrospectively analyzed, and 190 of them were diagnosed as acute local bacterial infection. The VCS parameters acquired from a Beckman Coulter LH750 haematology analyzer were investigated to determine which VCS parameters could indicate local bacterial infection in cancer patients with leucopenia caused by cytotoxic agents. VCS parameters of cancer patients were significantly affected by infection. For diagnosing bacterial infection of cancer patients, the best single indicator was mean monocyte light scatter (MMS) with a sensitivity of 95.12 % and a specificity of 58.82 % and the area under the curve (AUC) was 0.792. A combination of the following five parameters: mean neutrophil volume (MNV), MMS, mean lymphocyte conductivity (MLC), mean lymphocyte light scatter (MLS) and neutrophil volume distribution width (NDW) could provide a better index in diagnosing bacterial infection than any single parameter (sensitivity 75.8 %, specificity 64.72 %, AUC 0.763). Taking WBC counts into consideration, VCS parameters could better indicate bacterial infection for cancer patients with abnormal WBC level than that with normal WBC level. Aside from neutrophils, the VCS of monocytes and lymphocytes were also ideal indicators for bacterial infection. The combination of VCS parameters could increase the sensitivity, specificity and accuracy of diagnosis of cancer patients. [ABSTRACT FROM AUTHOR]

With bioactive SiO2-CaO-P2O5-CaF2 glass powder as the matrix and ammonium phosphate solution as setting liquid, β-tricalcium phosphate ceramic particles were added to produce a porous bone cement. The crystalline form, chemical composition and microstructure of this bone cement were observed and analysed by XRD, FTIR and SEM. The results indicate that the added β-tricalcium phosphate promotes the nucleation and growth of hydroxyapatite crystals. The degradation of β-tricalcium phosphate increases the apparent porosity of bone cement, but reduces its compressive strength. When β-tricalcium phosphate accounts for 30-wt-% of the total, the apparent porosity is approximately 45% by the 30th day of immersion in stimulated body fluid, and the compressive strength can still reach 20 MPa, which is conducive to the degradation, fusion and shape retention of bone cement. [ABSTRACT FROM AUTHOR]

A three-dimensional phase field model of β → α transformation in polycrystalline Ti–6Al–4V (wt.%) alloys is formulated and used to study variant selection and microstructure evolution under different processing conditions and starting β phase textures. Degrees of variant selection at both individual β grain and polycrystalline β volume element levels and their connections to the final micro- and macro-texture of α precipitates are analyzed and correlated with the processing parameters. It is found that local stresses in an elastically anisotropic and inhomogeneous polycrystalline volume element lead to obvious variant selection. Under certain pre-strains, a local volume element of a polycrystalline β sample considered in the simulations could end up with a relatively weak micro- and macro-texture of the transformed α phase if it has a strong starting β phase texture. Moreover, a Fix-End (clamped) boundary constraint to the volume element is found to be more favorable than a Free-End (relaxed) one in preventing the formation of strong transformation texture irrespective of the strength of the starting β phase texture. Other factors contributing to variant selection and transformation texture development are also discussed. The results could shed light on how to control processing conditions and internal stresses to reduce transformation texture at both the individual β grain and the polycrystalline volume element level. [ABSTRACT FROM AUTHOR]

Steel fibres were used to reinforce the layered targets with surface-to-surface combination. The two- and three-layer metal targets with a total thickness of 5 mm were fabricated by explosive welding. The damage mechanism and the anti-penetration performance of the targets were studied experimentally and numerically using the LS-DYNA 3D finite element code. The effects of layer number and fibre spacing density on the anti-penetration performance were discussed. The results show that the failure modes of the steel front plate were shearing and plugging, and that the failure mode of the aluminium rear plate was ductile prolonging deformation when the tied interface failed by tension (or shearing and plugging when the interface remained connected) for the two-layer target. For the three-layer target, the failure modes of the steel front plate and the aluminium middle plate were shearing and plugging, while the steel rear plate failed by ductile prolonging deformation. At the same time, the steel-fibres failed by bending and tensile deformation. The anti-penetration performance of the three-layer composite targets was better compared with the performance of the two-layer targets when the areal density and fibre spacing density were equal. The reinforced fibres will improve the anti-penetration performance of the targets, and the ballistic resistance decreased with an increase in the fibre spacing distance. [ABSTRACT FROM AUTHOR]

In order to analyze the influence of different thickness distributions on the antipenetration performance of layered plates with a good surface-to-surface combination, five types of two-layer steel/aluminum and three-layer steel/aluminum/steel plates with the same areal density were manufactured by the method of explosive welding. Ballistic experiments and numerical simulation were performed to study the antipenetration performance of the plates impacted by a spherical steel projectile of diameter 8 mm. A 14.5-mm riffled gun was used to launch the projectile, and the numerical simulation were carried out by using the LS-DYNA 3D explicit finite-element code. Effects of the number of layers, their thickness distribution, and total thickness on the antipenetration performance of the layered plates were investigated. Results showed that the antipenetration performance of the multilayer plates was better than that of a monolithic plate with the same areal density - the ballistic limit speed of the two-layer and three-layer plates, on the average, increased by 9.6 and 19.9% compared with that of the monolithic one. In addition, the antipenetration performance of the three-layer plates was better than that of the two-layer ones if the thickness of the steel and aluminum plates was same. The influence of layer thickness distribution on the antipenetration performance was more pronounced for the two-layer plates. [ABSTRACT FROM AUTHOR]

By systematic chemical substitution of Pt and Ni in the newly discovered superconductor Nb2PdS5 (Tc ~ 6 K), we study the evolution of its superconducting properties with doping, focusing on the behavior of the upper critical field Hc2. In contrast to the previous results of Se doping on S sites, superconductivity is found to be rather robust against the Pt and Ni dopants on the one-dimensional Pd chains. Most strikingly, the reduced Hc2, i.e., the ratio of Hc2/Tc, is seen to be significantly enhanced by the heavier Pt doping but suppressed in the Ni-doped counterparts, distinct from the nearly constant value in the Se-doped samples. Our findings therefore suggest that the upper critical field of this system can be modified in a tunable fashion by chemical doping on the Pd chains with elements of varying mass numbers. The spin-orbit coupling on the Pd sites, by inference, should play an important role in the observed superconductivity and on the large upper critical field beyond the Pauli pair-breaking field. [ABSTRACT FROM AUTHOR]

Objectives Cancer cells differ from normal body cells in their ability to divide indefinitely and to evade programmed cell death. Crosstalk between apoptosis and cell cycle processes promotes balance between proliferation and death, and limits population growth and survival of cells. However, intricate relationships between them and how they are able to manipulate the fate of cancer cells still remain to be clarified. Identification of key factors involved in both apoptosis and cell cycle regulation may help to address this problem. Materials and methods Identification of such key proteins was carried out, using a series of bioinformatics methods, such as network construction and key protein identification. Results In this study, we computationally constructed human apoptotic/cell cycle-related protein-protein interactions ( PPIs) networks from five experimentally supported protein interaction databases, and further integrated these high-throughput data sets into a Naïve Bayesian model to predict protein functional connections. On the basis of modified apoptotic/cell cycle related PPI networks, we calculated and ranked all protein members involved in apoptosis and cell cycle regulation. Our results not only identified some already known key proteins such as p53, Rb, Myc and Src but also found that the proteasome, Cullin family members, kinases and transcriptional repressors play important roles in regulating apoptosis and the cell cycle. Furthermore, we found that the top 100 proteins ranked by PeC were enriched in some pathways such as those of cancer, the proteasome, the cell cycle and Wnt signalling. Conclusions We constructed the global human apoptotic/cell cycle related PPI network based on five online databases, and a Naïve Bayesian model. In addition, we systematically identified apoptotic/cell cycle related key proteins in cancer cells. These findings may uncover intricate relationships between apoptosis and cell cycle processes and thus provide further new clues towards future anticancer drug discovery. [ABSTRACT FROM AUTHOR]

With Monte Carlo simulations, the nonsteady dynamic properties of a domain wall have been systematically investigated for the thermally activated creep state under an alternating driving field. Taking the driven randomfield Ising model in two dimensions as an example, two distinct growth stages of the domain interface are identified with both the correlation length and roughness function. One stage belongs to the universality class of the random depositions, and the other to that of the quenched Edwards-Wilkinson equation. In the latter case, due to the dynamic effect of overhangs, the domain interface may exhibit an intrinsic anomalous scaling behavior, different from that of the quenched Edwards-Wilkinson equation. [ABSTRACT FROM AUTHOR]

Abstract: The superelasticity and shape memory effect of shape memory alloys originate from martensitic transformations (MT) that produce self-accommodated polydomain structures. In order to understand the formation mechanism of various domain patterns, a phase field model of cubic to orthorhombic MT in NiTiPt and NiTiCu is formulated, through which microstructure evolutions dominated by long-range elastic interactions are simulated. A rich variety of morphological patterns are predicted and analyzed. In particular, autocatalytic events leading to multi-variant “pyramidal triangular” and “nested triangular” configurations in NiTiCu are revealed. These morphological patterns are beyond the reach of the classical phenomenological theory of martensitic crystallography (PTMC). The simulation predictions agree well with experimental observations. By distinguishing deformation variant from orientation variant, the theoretical connection and distinction between PTMC and phase field microelasticity theory are discussed, and their predictions are compared with experimental observations. [Copyright &y& Elsevier]

Abstract: Microstructural evolution during co-precipitation of γ′, γ″ and δ phases from a supersaturated γ matrix during aging of superalloy Inconel 718 (IN718) is investigated by computer simulation using the phase-field method. The precipitation model is quantitative, using as model inputs ab initio calculations of elastic constants, experimental data on lattice parameters, precipitate–matrix orientation relationship, interfacial energy of each individual precipitate phase and interdiffusivities, and a Ni–Nb–Al pseudo-ternary thermodynamic database specifically developed for IN718. In order to simulate statistically representative multiphase microstructures observed in the alloy, the Kim–Kim–Suzuki treatment of interfaces is employed. Simulation results show how alloy composition, lattice misfit, external stress, temperature and time affect precipitate microstructure and variant selection during isothermal aging, without any a priori assumptions about key microstructural features including size, shape, volume fraction and spatial distribution of different types of precipitates and different variants of the same precipitate phase. The shapes of precipitates and their coarsening kinetics are analyzed based on the two-dimensional moment invariant. The various multiphase microstructures generated by the simulations have been used as model inputs in a study to investigate how precipitate microstructure (in particular shape and spatial distribution) influences the strength of IN718. [Copyright &y& Elsevier]

To mine coal resources trapped under embankment dams safely and efficiently while, at the same time, disposing of waste rock, solid backfill mining has been proposed as a solution. The extreme value of dam deformation was obtained by analysing geological conditions in the area and structural characteristics of the dam. It was determined that the filling ratio of the working face and the equivalent mining height were the two key factors that control dam deformation. In addition, the extreme values of these two key factors varied with the distance between the working face and the embankment dam in a regular pattern. When mining was completed at the first working face in the pilot area, the maximum sink value of the dam was 42 mm, and the maximum horizontal strain was 0-16 mm m-1. Field demonstrations have shown that solid backfill mining is effective in controlling strata movement and surface deformation. [ABSTRACT FROM AUTHOR]

The recently discovered iron-based superconductors AyFe2-xSe2 (A = K, Rb, Cs, Tl) show a long-range antiferromagnetic order with an unexpectedly high transition temperature TN ~ 550 K and a unique √5 x √5 vacancy order. Taking the extended J1-J2 model as a minimal model, we investigate the finite-temperature magnetic phase transitions in a square lattice with a √5 x √5 vacancy superstructure by using large-scale Monte Carlo simulations. By the parallel tempering technique, the block spin checkerboard and stripe antiferromagnetic states are detected to be the ground states for three representative sets of model parameters. The short-time dynamic approach is applied to accurately determine the critical temperature as well as the static and dynamic exponents. Our results indicate that the dramatic enhancement of the critical temperature as observed in experiments should be mainly due to a combination of the vacancy order and the block lattice contraction. [ABSTRACT FROM AUTHOR]

Abstract: The phenomenon of high twin boundary fractions found experimentally for neighboring γ lamellae in fully lamellar TiAl alloys was investigated by phase-field simulations. The nucleation and growth processes during transformation that leads to the lamellar structure were simulated. In particular, the effects of coherency stress and the interfacial energy difference among different types of interfaces and undercooling on the nucleation mechanism were analyzed. It is found that the twin boundary fraction increases with increasing coherency elastic strain energy and increasing interfacial energy difference among different types of interfaces, and with decreasing undercooling. Depending on the relative contributions of these factors, the nucleation events simulated by the Langevin noises could be collective, correlated or independent. These findings could shed light on the control of twin boundary fraction within lamellar structures by adjusting alloy composition and cooling route. [Copyright &y& Elsevier]

Abstract: Series of ballistic experiments and numerical simulation were adopt to analyze the anti-penetration performance of explosively welded steel/aluminum, steel/aluminum/steel and aluminum/steel/aluminum plates impacted by spherical projectile vertically in this paper. A 14.5mm slip chamber gun was used to launch the spherical steel projectile with diameter of 6mm and the finite element code LS-DYNA 3D was used to simulate the penetration process. The effects of layer number, thickness, combination state of the interface and strength of the plates on the anti-penetration performance and damage mechanism were analyzed based on the results of experiment and numerical simulation. The results show that the damage mechanism of the front plate and middle plate is shearing and plugging, respectively, the steel rear plate is petalling deformation and the aluminum rear plate is ductile deformation impacted by projectile vertically. The anti-penetration performance of three-layered plates is better than that of two-layered plates with the same total thickness, especially the anti-penetration performance of three-layered steel/aluminum/steel welded plates is the best. As to two-layered steel/aluminum plates, the best anti-penetration performance can be attained when the thickness ratio is about 3:1. The good accordance of numerical and experimental results indicates that the finite element method (FEM) can predict the anti-penetration performance of multi-layered explosively welded plates well. [Copyright &y& Elsevier]

Abstract: A new precipitate phase named P-phase has recently been identified in (Ni,Pt)Ti high temperature shape memory alloys. In order to understand the roles played by the fine coherent P-phase precipitates in determining the martensitic transformation temperature (M s), strength of the B2 matrix phase, dimensional stability and shape memory effect of the alloys, a phase field model of P-phase precipitation is developed. Model inputs, including lattice parameters, precipitate–matrix orientation relationship, elastic constants and free energy data, are obtained from experimental characterization, ab initio calculations and thermodynamic databases. Through computer simulations, the shape and spatial distribution of the P-phase precipitates, as well as the compositional and stress fields around them, are quantitatively determined. On this basis, the elastic interaction energy between the P-phase precipitates and a martenstic nucleus is calculated. It is found that both the chemical non-uniformity and stress field associated with the P-phase precipitates are in favor of the martensitic transformation. Their relative contributions to the increase in M s temperature are quantified as a function of aging time and the result seems to agree with the experimental measurements. The shape and spatial distribution of the P-phase precipitates predicted by the simulations also agree well with experimental observations. [Copyright &y& Elsevier]

Abstract: The evolution of microtwins during high temperature creep deformation in a γ′ strengthened Ni-based superalloy has been investigated through a combination of creep testing, transmission electron microscopy (TEM), theoretical modeling, and computer simulation. Experimentally, microtwin nucleation sources were identified and their evolution was tracked by characterizing the deformation substructure at different stages of creep deformation. Deformation is highly localized around stress concentrators such as carbides, borides and serrated grain boundaries, which act as sources of a/2〈110〉 matrix-type dislocations. Due to fine channels between the γ′ particles, coupled with a low γ matrix stacking fault energy, the a/2〈110〉 matrix dislocations dissociate into a/6〈112〉 Shockley partials, which were commonly observed to be decorrelated from one another, creating extended intrinsic stacking faults in the γ matrix. Microtwins are common and form via Shockley partial dislocations, cooperatively shearing both the γ and γ′ phases on adjacent {111} glide planes. The TEM observations lead directly to an analysis of dislocation–precipitate interactions. The important processes of dislocation dissociation and decorrelation were modeled in detail through phase field simulations and theoretical analyses based on Orowan looping, providing a comprehensive insight into the microstructural features and applied stress conditions that favor the microtwinning deformation mode in γ′ strengthened Ni-based superalloys. [Copyright &y& Elsevier]

The authors propose an optimal resource allocation (RA) scheme for wireless multi-destination relay systems with orthogonal frequency division multiplexing (OFDM) modulation. The authors work is different in that they consider a practical downlink OFDM-based relay network, where a relay is used to help the source (base station) communicate with multiple out-of-range destinations (users), rather than a single destination (user) as assumed in most previous work. The proposed optimal RA scheme consists of subchannel allocation (SA), subchannel pairing and joint source-relay power allocation (PA). In particular, it is shown that both SA and joint source-relay PA play a dominant role in the three steps of RA. It is also demonstrated that the shorter the distance between the source and the relay, the more impact of multiuser diversity on the system capacity. By employing SA and joint source-relay PA only, a near-optimal performance can be achieved. This work can be extended to the multi-hop, multi-relay and multi-destination uplink/downlink OFDM system. [ABSTRACT FROM AUTHOR]

In this study, hybrid excitation doubly salient machines (HEDSMs) with parallel excitation structures are introduced. The three types of main poles in the HEDSMs are described and researched, respectively. A 30/20-pole HEDSM is analysed by the magnetic circuit means. Regulation performance of the air-gap fluxes of different main poles is presented. The expression of the total air-gap flux shows the ideal linear relationship between the total air-gap flux and the field excitation ampere-turns. The finite element analysis also verifies the perfect effect of the field control. And the flux line plots and no-load electromagnetic force (EMF) waveforms are presented. The experimental EMF waveforms and no-load characteristic curve are coincident with the simulation results. [ABSTRACT FROM AUTHOR]

Abstract: Precipitation of Ni4Ti3 plays a critical role in determining the martensitic transformation path and temperature in Ni–Ti shape memory alloys. In this study, the equilibrium shape of a coherent Ni4Ti3 precipitate and the concentration and stress fields around it are determined quantitatively using the phase field method. Most recent experimental data on lattice parameters, elastic constants, precipitate–matrix orientation relationship and thermodynamic database are used as model inputs. The effects of the concentration and stress fields on subsequent martensitic transformations are analyzed through interaction energy between a nucleating martensitic particle and the existing microstructure. Results indicate that R-phase formation prior to B19′ phase could be attributed to both direct elastic interaction and stress-induced spatial variation in concentration near Ni4Ti3 precipitates. The preferred nucleation sites for the R-phase are close to the broad side of the lenticular-shaped Ni4Ti3 precipitates, where tension normal to the habit plane is highest, and Ni concentration is lowest. [ABSTRACT FROM AUTHOR]

Abstract: Interdiffusion and microstructural stability in multilayers consisting of two nanostructured two-phase alloys were investigated using phase field simulations. A prototype ternary system containing a miscibility gap was used as the model system. Alloys with various compositions within the miscibility gap were chosen to form 20μm bilayer repeating units in the multilayers. The initial microstructures in the alloys were produced by spinodal decomposition, which yielded a uniform distribution of precipitates having an average diameter of about 50nm. Two types of multilayers were investigated; one in which the alloys in the repeating unit had the same matrix phase and the other in which the alloys had a different matrix phase. In general the microstructural instability measured as the size of the reaction zone increased with the increase in composition difference between the two initial alloys and in atomic mobility difference between the diffusing species. In particular, when the matrix phase was the same a precipitate-free zone (i.e. a single-phase layer) and a coarse interconnected precipitate zone formed at the interface between the two alloys, while when the matrix phase differed two precipitate-free zones formed at the interface. The microstructural instabilities were analyzed in terms of variations in the effective diffusivity with composition, which produced a singularity in the diffusion path at the initial alloy interface. The instability caused the diffusion path to exit the two phase region of the phase diagram and enter the single phase region. [Copyright &y& Elsevier]

Abstract: In this study, a novel vibration isolator is developed. The developed isolator possesses the characteristics of high-static–low-dynamic stiffness (HSLDS) and can act passively or semi-actively. The HSLDS property of the isolator is obtained by connecting a mechanical spring, in parallel with a magnetic spring that is constructed by a pair of electromagnets and a permanent magnet. The mechanical spring is a structural beam whose stiffness exhibits a hardening behavior. The stiffness of the magnetic spring can be positive or negative, depending on the polarity of the current to the electromagnets. A passive HSLDS isolator is obtained when the electromagnet current is zero. In the stiffness characterization study, the analytical model for each of the springs is established and the tuning parameters are identified. Using the stiffness models, the design optimization issues are investigated. In the experimental study, the effectiveness of the isolator for vibration isolation is tested. The analytical natural frequencies of the isolator are validated experimentally. The relationships between the displacement transmissibility and the exciting frequency are measured both under the passive mode and under the semi-active mode. The on-line tuning capability of the isolator is investigated. [Copyright &y& Elsevier]

Abstract: La2NiO4 compounds were prepared by a modified sol–gel auto-combustion method, which is a low-temperature combustion synthesis procedure using microwave-assisted sol–gel as precursors. The high-temperature transport properties of the samples were investigated. The band structure, total density of states (DOS), and partial density of states (PDOS) of low-temperature orthorhombic (Bmab) phase and high-temperature tetragonal (I4/mmm) phase for La2NiO4 were calculated in order to study the transport properties of the as-obtained samples. [Copyright &y& Elsevier]

A phase field model is developed to simulate γ' rafting in single crystal Ni-Al under the influence of external stress. Lattice and modulus mismatch between the γ and γ' phases and γ channel plasticity are considered simultaneously in the model. To increase the computational efficiency, an average plastic strain is introduced to describe the channel plasticity based on experimental observation of dislocation density. With the elastic moduli of both phases and their lattice misfit at the aging temperature from direct experimental measurement, and thermodynamic and mobility data from available databases as inputs, the simulation results show that the type of rafting is determined by channel plasticity while modulus mismatch between the precipitate and the matrix affects only the kinetics of the rafting process. The model can be used to quickly estimate the type of rafting and, more importantly, the time when rafts fully develop. [ABSTRACT FROM AUTHOR]

Abstract: Directional coarsening (rafting) of γ′ precipitates in single-crystal Ni–Al alloys under external load is investigated by three-dimensional computer simulations. Contributions from modulus mismatch between the precipitate and matrix phases and from channel plasticity are considered. The simulation technique is based on a phase field model that captures spatiotemporal evolution of precipitate microstructure in elastically anisotropic and inhomogeneous systems. Channel plasticity is incorporated in the model through the introduction of an effective plastic strain that is formulated based on dislocation contents in the γ channels. Experimental data on lattice misfit, elastic moduli, applied stress and dislocation density in γ channels are used as model inputs. The driving force for rafting is monitored continuously by tracking the change in chemical potential difference between different types of γ channels after an external stress is applied until rafting completes. Quantitative comparisons of the rafting driving force and rafting completion time obtained from the simulations confirm the dominant role of channel plasticity, indicating that the rafting direction is determined by channel plasticity rather than by modulus inhomogeneity. However, elastic inhomogeneity also makes a significant contribution to the driving force for rafting, especially during the first several hours after the external load is applied. [Copyright &y& Elsevier]

Abstract: SrO(SrTiO3) n compounds were prepared by a modified sol–gel self-propagating combustion, which is a low-temperature combustion synthesis procedure using microwave-assisted sol-gel as precursors. The thermal treating conditions were determined by DTA/TG analysis of the powders. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used for the sample characterization. The results confirm that the high temperature and long reaction time which occur in classical solid-state reaction method are avoided. The band structure, total density of states (DOS), and partial density of states (PDOS) of SrO(SrTiO3) n were calculated in order to study the electronic structures of SrO(SrTiO3) n . [Copyright &y& Elsevier]