[Risk prediction and function evaluation by T-cell epitope model and expression model of HLA-DPB1 mismatching in unrelated-donor hematopoietic stem cell transplantations].

Objective: To evaluate the risk prediction and assessment function of HLA-DPB1 T-cell epitope (TCE) model and expression model in human leukocyte antigen (HLA)-matched unrelated hematopoietic stem cell transplantation (MUD-HSCT) with HLA-DPB1 mismatching. Methods: A total of 364 (182 pairs) potential MUD-HSCT donors and recipients confirmed by HLA high-resolution typing in Shaanxi Blood Center from 2016 to 2019 were analyzed retrospectively. Of the 182 recipients, there were 121 males and 61 females with an average age of (26.3±14.2) years. Of the 182 donors, there were 148 males and 34 females with an average age of (33.7±7.5) years. Polymerase chain reaction-sequence-based typing (PCR-SBT), next-generation sequencing (NGS) and polymerase chain reaction-sequence specific oligonucleotide probe (PCR-SSO) based on LABScan®3D platform were used for high-resolution typing of HLA-A, B, C, DRB1, DQB1, DPB1 gene, and PCR-SBT was used for single nucleotide polymorphism (SNP) typing. TCE model and expression model were used to predict and evaluate the HLA-DPB1 mismatch pattern and acute graft-versus-host-disease (aGVHD) risk. Results: A total of 26 HLA-DPB1 alleles and their 3'-UTR rs9277534 SNP genotypes were detected in this study population, and two new alleles HLA-DPB1*1052∶01 and HLA-DPB1*1119∶01 were found and officially named. The overall mismatch rate of HLA-DPB1 in MUD-HSCT donors and recipients was 90.66% (165/182). In TCE model, the HLA-DPB1 mismatch rates of permissible mismatch (PM) and non-permissible mismatch (non-PM) were 47.80% (87/182) and 42.86% (78/182), respectively. The non-PM in GvH direction was 13.73% (25/182), and which in HvG direction was 29.12% (53/182). A total of 73 pairs of donors and recipients in TCE model met the evaluation criteria of expression model. Among of TCE PM group, recipient DP5 mismatches accounted for 34.25% (25/73) were predicted as aGVHD high risk according to expression model. For the TCE non-PM group, both the recipient DP2 mismatches of 6.85% (5/73) and recipient DP5 mismatches of 10.86% (8/73) were predicted to be at high risk for aGVHD. Risk prediction by TCE model and expression model was 27.27% concordant and 16.97% unconcordant. Conclusions: TCE model and expression model are effective tools to predict aGVHD risk of MUD-HSCT. Comprehensive application of the two models is helpful to the hierarchical assessment of HSCT risk.

[Analysis of verification results of protective effects of hearing protectors in different industries].

Objective: To get insight into the current practice of noise reduction effect of workers as they wore hearing protectors in different domestic enterprises and the possible affected factors. Methods: From October 2020 to April 2021, using a random sampling method, 1197 workers exposed to noise in petrochemical factories, textile factories, and parts manufacturing factories were selected as the study subjects. The noise reduction effect of hearing protectors worn by workers in daily use was tested using a hearing protector suitability testing system. The personal sound attenuation level (PAR) was compared among workers in three enterprises, Targeted intervention and repetitive testing were conducted for workers who did not meet the noise reduction effect required by the enterprise, and the changes in PAR of workers before and after the intervention were compared. The comparison of baseline PARs between two or more groups was performed using the Mann Whitney test, the comparison of baseline PARs with post intervention PARs was performed using the Wilcoxon signed rank sum test, and the comparison of qualitative data between two or more groups was performed using the Chi square test. Results: The median baseline PAR for all workers was 15 dB. Men, age<30 years old, education level at or above college level, working experience of 5 to 15 years, and those who used hearing protectors for 5 to 15 years had higher PARs, with statistically significant differences (P<0.05). The median difference in baseline PAR among workers from three enterprises was statistically significant (H=175.06, P<0.01). The median PAR of subjects who did not pass the baseline increased from 3 dB to 21 dB after intervention (Z=-27.92, P<0.01) . Conclusion: Some workers wearing hearing protectors do not meet the required PAR, and low PARs may be related to incorrect wearing methods and incorrect selection of hearing protectors. As a tool for testing, training, and assisting in selection, the hearing protector suitability testing system is of great significance for worker hearing protection.

[The short-term and long-term prognostic analysis in patients with chronic total occlusion acute non-ST segment elevation myocardial infarction].

Objectives: To investigate the clinical impacts of chronic total occlusion (CTO) in acute non-ST segment elevation myocardial infarction (NSTEMI) patients underwent primary percutaneous coronary intervention (PCI). Methods: A total of 2 271 acute NSTEMI patients underwent primary PCI from China Acute Myocardial Infarction Registry were enrolled in this study and divided into the CTO group and the non-CTO group according to the angiography. The primary endpoint was in-hospital mortality and mortality during a 2-year follow-up. The secondary endpoint was major adverse cardiovascular events (MACE) including revascularization, death, re-myocardial infarction, heart failure readmission, stroke and major bleeding. Results: Thirteen-point four percent of the total acute NSTEMI patients had concurrent CTO. In-hospital mortality (3.6% vs. 1.4%, P<0.01) and 2-year mortality (9.0% vs. 5.1%, P<0.01) were significantly higher in the CTO group than those in the non-CTO group, respectively. Multiple regression analyses showed that chronic obstructive pulmonary disease (HR 7.28, 95%CI 1.50-35.35, P=0.01) was an independent risk factor of in-hospital mortality, and advanced age (HR 1.04, 95%CI 1.01-1.07, P<0.01), and low levels of ejection fraction (HR 0.95, 95%CI 0.93-0.98, P<0.01) were independent risk factors of 2-year mortality. CTO (HR1.67, 95%CI 1.10-2.54, P=0.02) was an independent risk factor of revascularization, but not a risk factor of mortality. Conclusions: Although acute NSTEMI patients concurrent with CTO had higher mortality, CTO was only an independent risk factor of revascularization, but not of mortality. Advanced age and low levels of ejection fraction were independent risk factors of long-term death among acute NSTEMI patients.

[Risk assessment on noise-induced hearing loss of 488 workers in a petrochemical plant].

Objective: To assess the risk of noise-induced hearing loss in workers from a petrochemical plant. Methods: In October 2020, 488 male workers exposed to noise in a petrochemical plant in Guangdong Province were selected by cluster sampling. Acoustics-Estimation of Noise-Induced Hearing Loss (ISO 1999: 2013) was used to assess the risk of noise-induced hearing loss of workers, and individual fit testing was used to evaluate the sound attenuation obtained by the workers. The risk assessment results and fitness test results of workers with different hearing levels were compared. Results: The average noise exposure equivalent sound level of the workers in the petrochemical plant was 86.7 dB (A) . The median of PARs (personal attenuation ratings) was 16 (4, 23) dB. There were statistically significant differences in age and service years among workers with different hearing results (P<0.05) , but no statistically significant differences in noise intensity and PARs (P>0.05) . According to risk assessment results of ISO 1999: 2013, the current risk of high-frequency hearing loss in 488 workers were negligible risk and acceptable risk. The risk of noise-induced deafness weredivided into three levels: negligible risk in 452 workers (92.7%) , medium risk in 27 workers (5.5%) and high risk in 9 workers (1.8%) . The risk of high-frequency hearing loss in next 5 to 15 years for workers with noise exposure level of >94 to 97 dB and >97 dB or above would be medium risk or above. The risk of noise-induced deafness in next 5 to 15 years for workers exposed to noise withlevel of 91 to 94 dB would be medium risk or above. Conclusion: The risk of noise-induced hearing loss in workers from the petrochemical plant is high in next 5 to 15 years, and noise prevention and control measures need to be strengthened. ISO1999: 2013 assessment method may underestimate the risk of hearing loss among workers.

[The acute and long-term outcome of patients with ST segment elevation myocardial infarction concurrent with chronic total occlusion].

Objective: To evaluate the acute and long-term outcome of patients with ST segment elevation myocardial infarction (STEMI) concurrent with chronic total occlusion (CTO) undergoing primary percutaneous coronary intervention (PCI). Methods: 11 905 STEMI patients from the China Acute Myocardial Infarction Registry were enrolled in this study and divided into CTO group and non-CTO group according to the angiography results of primary PCI. 1∶3 propensity score matching was used to match the patients between the two groups. The primary endpoint was in-hospital mortality and mortality at 1-year post PCI. The secondary endpoint was major adverse cardiovascular events (MACE) including death, re-myocardial infarction, revascularization, heart failure associated readmission, stroke and major bleeding at 1-year post PCI. Results: There were 931 CTO patients (7.8%) in this cohort (male=755 (81.1%), mean age (62.2±11.4 years)). The rest 10 974 patients were STEMI without CTO (male=8 829 (80.5%),mean age (60.0±11.8) years). After propensity score matching, 896 patients were enrolled in CTO group and 2 688 in non-CTO group. In-hospital mortality was significantly higher in the CTO group than in non-CTO group (4.2% vs. 2.4%, P=0.006). The ratio of all cause death, cardiac death, and MACE at 1-year follow up was also significantly higher in the CTO group than in non-CTO group (8.5% vs. 4.4%, P<0.001, 5.3% vs. 2.6%, P=0.001, 35.1% vs. 23.3%, P<0.001, respectively). Multiple regression analysis showed that CTO (HR=1.54, 95%CI 1.06-2.22, P=0.022), advanced age (HR=1.06, 95%CI 1.04-1.08, P<0.001), and previous heart failure history (HR=4.10, 95%CI 1.90-8.83, P<0.001) were independent risk factors of 1-year mortality. Conclusions: The in-hospital and 1-year mortality increased significantly in STEMI patients concurrent with CTO. CTO, advanced age and history of heart failure are independent risk factors of 1-year death among STEMI patients.

Associations of IL-1ß and IL-6 gene polymorphisms with Parkinson's disease.

OBJECTIVE: The aim of this study was to explore the associations of interleukin-1ß (IL-1ß) and IL-6 gene polymorphisms with the pathogenesis of Parkinson's disease. PATIENTS AND METHODS: A total of 200 patients with Parkinson's disease in our hospital were collected as the disease group. Meanwhile, 200 healthy subjects were taken as the control group. Peripheral blood samples were drawn from all research subjects. The polymorphic regions of IL-1ß and IL-6 were amplified via polymerase chain reaction (PCR). Moreover, the polymorphisms were detected and analyzed, followed by further analysis based on the changes in gene expressions and Hoehn-Yahr grade of patients. RESULTS: The allele distributions at IL-1ß rs571556428 (p=0.015) and IL-6 rs543214973 (p=0.012) were statistically different between control group and disease group. In disease group, the G allele frequency at IL-1ß rs571556428 and T allele frequency at IL-6 rs543214973 were significantly higher (p<0.05). Genotype distributions at IL-1ß rs572292175 (p=0.017) and rs571556428 (p=0.000), and IL-6 rs543214973 (p=0.002) in disease group were also different from those in control group. In addition, the frequencies of CT genotype at IL-1ß rs572292175, AA genotype at IL-1ß rs571556428 and AA genotype at IL-6 rs543214973 in disease group were significantly lower (p<0.05). After modeling and analysis, it was found that the distribution of recessive model at IL-1ß rs571556428 (p=0.012) and IL-6 rs543214973 (p=0.014) in disease group exhibited significant differences from those in control group. The frequencies of TA haplotype at IL-1ß rs572292175 and rs571556428 (p=0.038) and GA haplotype at IL-6 rs1474348 and rs543214973 (p=0.047) in disease group were lower than those in control group (p<0.05). The polymorphisms at IL-1ß rs571556428 and IL-6 rs1474348 were significantly associated with gene expression (p<0.05). Moreover, the expressions of IL-1ß and IL-6 rose significantly in patients with GG genotype at rs571556428 and CG genotype at rs1474348, respectively (p<0.05). Furthermore, the polymorphism at IL-1ß rs571556428 was significantly correlated with the grade of Parkinson's disease (p=0.000). Parkinson's disease was in a higher grade (grade 4-5) in patients with AA genotype, whereas in a lower grade (grade 1-2) in patients with GG and AG genotypes. CONCLUSIONS: IL-1ß and IL-6 gene polymorphisms are significantly associated with the pathogenesis of Parkinson's disease.

Super tough magnetic hydrogels for remotely triggered shape morphing.

Despite their potential in various fields such as soft robots, drug delivery and biomedical engineering, magnetic hydrogels have always been limited by their poor mechanical properties. Here a universal soaking strategy has been presented to synthesize tough magnetic nanocomposite (NC) hydrogels. We can simultaneously solve two common issues for magnetic hydrogels: the poor mechanical properties and poor distribution of magnetic particles. The toughness of the magnetic NC hydrogel achieves approximately 11 000 J m-2. The outstanding properties of tough magnetic hydrogels will enable myriad applications. Here we demonstrate a new application for remotely triggered shape morphing. Heterogeneous structures based on magnetic hydrogels are shown to evolve into bio-inspired three-dimensional (3D) shapes (lotus flowers) from 2D-structured sheets. The self-folding of the structure is controlled by the magnetothermal effect in an alternating magnetic field. The capability to control the shape morphing of a multi-material system by a magnetic field may emerge as a new general strategy for programming complex soft structures.

[Intravenous sedation with midazolam and propofol target controlled infusion on patients'perioperative anxiety under the mandibular third molar extraction].

OBJECTIVE: To evaluate whether midazolam with propofol target controlled infusion (TCI) intravenous sedation during the mandibular third molar extraction influences patients'perioperative anxiety. METHODS: The subjects were patients who planned to undergo the mandibular third molar extraction in Peking University School and Hospital of Stomatology, whose state anxiety inventory (SAI) scores were≥38 at the initial visit. They were divided into intravenous sedation group (IVS) and local anesthesia group (LA) on the basis of the planned intravenous sedation. Each group was divided into two subgroups according to the overall SAI scores at the initial visit: IVS-I, LA-I (SAI: 38-50) and IVS-II, LA-II (SAI: 51-80). The anxiety before and after the surgery was evaluated by the SAI scores at the initial visit (T1), before surgery (T2) and 7 days after surgery (T3). The anxiety during the surgery was evaluated by the heart rate, blood pressure and visual analogue scale (VAS) scores. RESULTS: There were no significant differences on SAI at T1, T2, and T3 in the two groups (P>0.05). The heart rate, blood pressure and VAS pain scores of IVS group were significantly lower than those of LA group during the surgery (P<0.001). CONCLUSION: Intravenous sedation with midazolam and propofol TCI was effective on the patients' anxiety during the third molar extraction, which successfully made the patients more comfortable and their heart rate, blood pressure and oxygen saturation more stable during the surgery. But there were no significant differences on the patients'anxiety at the initial visit (T1), before surgery (T2) and 7 days after surgery (T3) according to the SAI scores in the two groups.

3D printed reversible shape changing soft actuators assisted by liquid crystal elastomers.

In this work, we advance printed active composites by combining 3D printing, printed electronics, and liquid crystal elastomers (LCEs) to achieve soft actuators with free-standing two-way shape changing behaviors. Incorporated LCE strips are activated by Joule heating produced by printed conductive wires, while uniaxial deformation of the LCE strip is utilized as a driving force to achieve bending in the printed composite. The bending behavior of laminated hinges is first characterized in order to obtain a precise control of actuation, which is then exploited to actuate four demonstrative designs: a morphing airplane, a miura-ori structure, a cubic box, and a soft crawler. The soft morphing airplane and miura-ori structure are designed and fabricated with multiple laminated hinges to demonstrate the synergistic actions during actuation. The cubic box is constructed to show the capability of sequential folding by implementing multiple groups of conductive wires to achieve accurately addressable heating with temporal control. Finally, the two-way transformation is utilized as a driving force for the locomotion of a soft crawler stimulated by a periodic rectangular wave current. These examples show the great potential of using the hybrid 3D printing and pick-and-place method and using LCEs to achieve controllable shape change structures for a variety of potential practical applications.

Gender difference in radiotherapy-induced carotid stenosis.

Radiotherapy (RT) is often the first choice of treatment for cancer of the larynx. Studies have shown that the incidence of carotid stenosis (CS) after radiotherapy of laryngeal cancer is increasing, and that gender difference in radiotherapy-induced side effects exist. Thus, we examined the gender difference in the incidence of CS and the impact of microinflammatory factors after radiotherapy. We reported this study on patients who received radiotherapy as part of the treatment for laryngeal cancer in the Jilin Province in China. One hundred sixty-four males and 152 females were treated with radiotherapy between 2006 and 2016. The carotid diameter was determined by measuring carotid intima-media thickness in the common, external and internal carotid artery. Microinflammatory conditions were assessed by measuring the level of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α). Other studied risk factors included age, treatment modalities, radiation dose and energy, the height of the radiation field, and the follow-up time. CS was detected in 161 (50.9%) of the 316 patients. Carotid stenosis was mainly clinically unsuspected, two patients had anamnesis of unconsciousness. Importantly, fewer women (36.1%) had CS than men (64.6%) (p=0.004). Furthermore, male patients showed higher serum levels of hs-CRP, IL-6, and TNF-α. Taken together, our study suggested that women underoing radiotherapy of laryngeal cancer are less likely to have CS than men. Therefore, routine assessment after irradiation of laryngeal cancer seems necessary for clinical detection of asymptomatic CS, particularly in male patients.

Enhanced surface ozone during the heat wave of 2013 in Yangtze River Delta region, China.

Under the background of global warming, occurrence of heat waves has increased in most part of Europe, Asia and Australia along with enhanced ozone level. In this paper, observational air temperature and surface ozone in the Yangtze River Delta (YRD) region of China during summer of 2013, and the regional chemistry-climate model (RegCM-CHEM4) were applied to explore the relationship between heat wave and elevated ground-level ozone. Observations indicated that YRD experienced severe heat waves with maximum temperature up to 41.1°C, 6.1°C higher than the definition of heat wave in China, and can last for as long as 27days. Maximum ozone reached 160.5ppb, exceeding the national air quality standard (secondary level) as 74.7ppb. Moreover, ozone was found to increase at a rate of 4-5ppbK-1 within the temperature range of 28-38°C, but decrease by a rate of -1.3~-1.7ppbK-1 under extremely high temperature. A typical heat wave case (HW: 24/7-31/7) and non-heat wave case (NHW: 5/6-12/6) were selected to investigate the mechanism between heavy ozone and heat waves. It was found that chemical reactions play the most important role in ozone formation during HW days, which result in 12ppb ozone enhancement compared to NHW days. Chemical formation of ozone can be influenced by several factors. During heat waves, a more stagnant condition, controlled by anti-cyclone with sink airflow, led to less water vapor in YRD from south and contributed to less cloud cover, which favored a strong solar radiation environment and ozone significantly increasing. High temperature also slightly promote the effect of vertical turbulence and horizontal advection, which beneficial to ozone remove, but the magnitude is much smaller than chemical effect. Our study suggests that the chemical reaction will potentially lead to substantial elevated ozone in a warmer climate, which should be taken into account in future ozone related issues.

A Simple Automated Method for Detecting Recurrence in High-Grade Glioma.

Our aim was to develop an automated multiparametric MR imaging analysis of routinely acquired imaging sequences to identify areas of focally recurrent high-grade glioma. Data from 141 patients treated with radiation therapy with a diagnosis of high-grade glioma were reviewed. Strict inclusion/exclusion criteria identified a homogeneous cohort of 12 patients with a nodular recurrence of high-grade glioma that was amenable to focal re-irradiation (cohort 1). T1WI, FLAIR, and DWI data were used to create subtraction maps across time points. Linear regression was performed to identify the pattern of change in these 3 imaging sequences that best correlated with recurrence. The ability of these parameters to guide treatment decisions in individual patients was assessed in a separate cohort of 4 patients who were treated with radiosurgery for recurrent high-grade glioma (cohort 2). A leave-one-out analysis of cohort 1 revealed that automated subtraction maps consistently predicted the radiologist-identified area of recurrence (median area under the receiver operating characteristic curve = 0.91). The regression model was tested in preradiosurgery MRI in cohort 2 and identified 8 recurrent lesions. Six lesions were treated with radiosurgery and were controlled on follow-up imaging, but the remaining 2 lesions were not treated and progressed, consistent with the predictions of the model. Multiparametric subtraction maps can predict areas of nodular progression in patients with previously treated high-grade gliomas. This automated method based on routine imaging sequences is a valuable tool to be prospectively validated in subsequent studies of treatment planning and posttreatment surveillance.

Long-Term Outcome of Liver Transplant Recipients After the Development of Renal Failure Requiring Dialysis: A Study Using the National Health Insurance Database in Taiwan.

BACKGROUND: The aims of this study were to identify the incidence of renal failure requiring dialysis and to investigate the long-term outcome after renal failure in liver transplantation (LT) patients. METHODS: The primary database used was the Taiwan National Health Insurance Research Database. Subjects with LT from 1997 to 2009 were included. Patients were grouped into the dialysis cohort if they once received hemodialysis owing to any pattern of renal failure during peri-transplantation periods or after LT. Otherwise, they were categorized into the nondialysis cohort. We conducted a retrospective observational study on the correlation of renal failure requiring dialysis and its effect on LT recipients. RESULTS: The analysis included data of 1,771 LT recipients with a mean follow-up time of 3.8 ± 2.9 years. The mean age was 43.2 ± 19.3 years, and 69.4% were male. Overall patient survival was 86.2% at 1 year, 82.2% at 3 years, and 80.5% at 5 years. Renal failure requiring dialysis had developed in the 323 patients (18.2%). Among them, 26 individuals (1.5%) had progressed to end-stage renal disease without renal recovery after perioperative hemodialysis. Individuals who developed renal failure requiring dialysis had a higher mortality compared with LT recipients never requiring dialysis (hazard ratio, 8.75; 95% confidence interval, 7.0-10.9). CONCLUSIONS: Renal failure requiring dialysis development after LT is common and carries high mortality in Chinese liver allograft recipients. Recognizing risk factors permits the timely institution of proper treatment, which is the key to reducing untoward outcomes.

Primary small cell carcinoma of the vagina with pulmonary metastasis: a case report.

Primary small cell carcinoma of the vagina is extremely rare; no standard treatment has been established despite it being highly aggressive. Here, the authors report on a 43-year-old patient who had a mass on the clitoris and no uterine or bilateral adnexal involvement. Vaginal wall biopsy revealed malignant small cell carcinoma. The carcinoma was composed of epithelial cells with round, hyperchromatic nuclei containing few distinct nucleoli, and scanty cytoplasm. Chest computerized axial tomography and pathological bronchoscopy revealed bilateral pulmonary metastases. She received radiotherapy combined with six cycles of chemotherapy (paclitaxel plus cisplatin), and achieved complete response, with complete suppression of the mass and lung metastases. There was no sign of tumor recurrence or distant metastases after 21 months of follow-up.

SOX4 is a potential prognostic factor in human cancers: a systematic review and meta-analysis.

OBJECTIVE: The aim of the this study was to analyze the status of sex-determining region Y-related high-mobility group box 4 (SOX4) expression in varied human cancers and its correlation with overall survival in patients with human cancers. METHODS: To observe initially the expression status of SOX4 in twenty kinds of human cancers at protein database (The Human Protein Atlas). We systematically and carefully searched the studies from electronic databases and seriously identified according to eligibility criteria. The correlation between SOX4 expression and overall survival in human cancers was evaluated through Review Manager. RESULTS: We found that SOX4 expression was significantly positive in most types of human cancer tissues, and the positive rate of SOX4 expression was about 78 % in overall cancer tissues. Furthermore, a total of 10 studies which included 1348 cancer patients were included in the final analysis. Meta-analysis showed that SOX4 overexpression was correlated with a poor overall survival and the pooled hazard ratio (HR), and corresponding 95 % confidence interval (CI) was 1.67 (95 % CI 1.01-2.78). From subgroup analyses, we present evidence that SOX4 overexpression was an unfavorable prognostic factor for colorectal cancer patients' recurrence-free survival and gastric cancer patients' overall survival, and the pooled HRs (95 % CI) were 1.73 (95 % CI 1.04-2.88) and 3.74 (95 % CI 1.04-13.45), respectively. CONCLUSIONS: In summary, SOX4 is a potential prognostic biomarker in human cancers.

Cyclic Deformation in Metallic Glasses.

Despite the utmost importance and decades of experimental studies on fatigue in metallic glasses (MGs), there has been so far little or no atomic-level understanding of the mechanisms involved. Here we perform molecular dynamics simulations of tension-compression fatigue in Cu50Zr50 MGs under strain-controlled cyclic loading. It is shown that the shear band (SB) initiation under cyclic loading is distinctly different from that under monotonic loading. Under cyclic loading, SB initiation takes place when aggregates of shear transformation zones (STZs) accumulating at the MG surface reach a critical size comparable to the SB width, and the accumulation of STZs follows a power law with rate depending on the applied strain. It is further shown that almost the entire fatigue life of nanoscale MGs under low cycle fatigue is spent in the SB-initiation stage, similar to that of crystalline materials. Furthermore, a qualitative investigation of the effect of cycling frequency on the fatigue behavior of MGs suggests that higher cycling frequency leads to more cycles to failure. The present study sheds light on the fundamental fatigue mechanisms of MGs that could be useful in developing strategies for their engineering applications.

Strong and superplastic nanoglass.

The strength-ductility tradeoff has been a common long-standing dilemma in materials science. For example, superplasticity with a tradeoff in strength has been reported for Cu50Zr50 nanoglass (NG) with grain sizes below 5 nm. Here we report an improvement in strength without sacrificing superplasticity in Cu50Zr50 NG by using a bimodal grain size distribution. Our results reveal that large grains impart high strength, which is in striking contrast to the physical origin of the improvement in strength reported in the traditional nanostructured metals/alloys. Furthermore, the mechanical properties of NG with a bimodal nanostructure depend critically upon the fraction of large grains. By increasing the fraction of the large grains, a transition from superplastic flow to failure by shear banding is clearly observed. We expect that these results will be useful in the development of a novel strong and superplastic NG.

Identification of key micro-organisms involved in Douchi fermentation by statistical analysis and their use in an experimental fermentation.

AIMS: To screen and identify safe micro-organisms used during Douchi fermentation, and verify the feasibility of producing high-quality Douchi using these identified micro-organisms. METHODS AND RESULTS: PCR-denaturing gradient gel electrophoresis (DGGE) and automatic amino-acid analyser were used to investigate the microbial diversity and free amino acids (FAAs) content of 10 commercial Douchi samples. The correlations between microbial communities and FAAs were analysed by statistical analysis. Ten strains with significant positive correlation were identified. Then an experiment on Douchi fermentation by identified strains was carried out, and the nutritional composition in Douchi was analysed. Results showed that FAAs and relative content of isoflavone aglycones in verification Douchi samples were generally higher than those in commercial Douchi samples. CONCLUSIONS: Our study indicated that fungi, yeasts, Bacillus and lactic acid bacteria were the key players in Douchi fermentation, and with identified probiotic micro-organisms participating in fermentation, a higher quality Douchi product was produced. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report to analyse and confirm the key micro-organisms during Douchi fermentation by statistical analysis. This work proves fermentation micro-organisms to be the key influencing factor of Douchi quality, and demonstrates the feasibility of fermenting Douchi using identified starter micro-organisms.