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The effects of aging on martensitic transformation and microhardness were investigated for Ni53Mn23·5Ga18·5Ti5 ferromagnetic shape memory alloy. The results show that precipitation has obvious effect on martensitic transformation temperature and the microhardness increases with increasing aging temperature up to 973 K, and then decreases gradually with the further increase in aging temperature. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the mechanical properties and shape-memory behaviors of poly(L-actide-co-e-caprolactone) (PCLA) copolymers. It notes that a variety of chemical compositions were used to synthesize a series of biodegradable PCLA copolymers. Results of the study showed that the copolymer compositions influenced the mechanical properties significantly. It also found a decline in the tensile strength of copolymers due to an increase in e-caprolactone content.

The thermal properties, crystalline structure and shape memory effects of poly( l-lactide) (PLLA) and poly( l-lactide-co-ε-caprolactone) (PCLA) copolymers are systematically investigated by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and tensile tests. The effects of the deformation strain on the shape recovery rate and recovery stress are also revealed. The polymers have the PLLA crystal and the amorphous phase, which are served as the fixed phase and reversible phase, respectively. The shape recovery rate and the recovery stress are significantly affected by the compositions and the deformation strain. With the increase of the deformation strain, the shape recovery rate decrease and higher shape recovery rate can be obtained in the polymers which have higher ε-CL content. However, the variation of recovery stress with the deformation strain is quite different and the maximum recovery stress of all polymers exceeds 3 MPa. [ABSTRACT FROM AUTHOR]

A Heusler Ni50Mn29Ga16Gd5 alloy with a high transformation temperature has been obtained by substituting 5 at% Gd for Ga in a ternary Ni50Mn29Ga21 ferromagnetic shape memory alloy. The microstructure and phase transformations in the Ni50Mn29Ga16Gd5 alloy have been investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and differential scanning calorimetry. It is shown that the microstructure of the Ni50Mn29Ga16Gd5 alloy consists of matrix and hexagonal Gd (Ni,Mn)4Ga phase, which indicates a eutectic structure composed of these two phases. One-step thermoelastic martensitic transformation occurs in this quaternary alloy. Ni50Mn29Ga16Gd5 alloy exhibits a martensite transformation start temperature up to 524 K, approximately 200 K higher than that of Ni50Mn29Ga21 alloy. At room temperature, non-modulated martensite with twin substructure is observed in Ni50Mn29Ga16Gd5 alloy. [ABSTRACT FROM AUTHOR]

Along with the rapid growth of the national economy in China, the electric utility is faced with an ever rising demand for electricity and the problem to solve large capacity power transmission. Under the support of the High Technology Research & Development Program of China, a 1.5 kA/10.5 kV 10-m long 3-phases HTS transmission power cable and a 75-m long, 3-phase, 10.5 kV/1.5 kA HTS power cable have been developed successfully by the Institute of Electrical Engineering, Chinese Academy of Sciences. The 75-m long HTS power cable operates now at a local live distribution grid of 6.6 kV to supply electric power for Changtong's factory in Baiyin, Gansu Province. The cable operates stably and reliably over 7000 hours since December 2004. [ABSTRACT FROM AUTHOR]

The effect of annealing treatment and thermal cycling on the phase transformation behaviour of Ni-Mn-Ga alloy prepared by arc melting technology has been investigated. The results show that the main transformation parameters decrease in a few initial thermal cycles, and then stabilise with further cycling. The transformation temperature interval decreases with an increase of annealing temperature. As cast material exhibits a columnar grain microstructure, while annealed material exhibits coarsened grains with clearly martensitic plates. When the alloy is annealed at 1073 K, both the martensite start temperature M[sub s] and the austenite finish temperature A[sub f] decrease, while the martensite finish temperature M[sub f] and the austenite start temperature A[sub s] increase with an increase in annealing time. This implies that the chemical order degree of the parent phase increases with increasing annealing time, which causes the chemical driving force for martensitic transformation to decrease. [ABSTRACT FROM AUTHOR]

The article determines the magnetic-field induced strain (MFIS) along the direction of Ni50.5Mn26.2Ga23.4 single crystal at different temperatures. It is interesting to find that the MFIS between the temperature of Ms and Mf is larger than the MFIS below Mf. The specimen used in this study was cut from a bulk single crystal with composition of Ni50.5Mn26.2Ga23.4. The single crystal was grown in the direction according to the cubic parent phase using a Czochralski instrument with a cold crucible system. The magnetic field induced strain was measured by a strain-gauge attached to the sample which was placed in a furnace between the electromagnets.

Stress-free and two-way thermoelastic shape memory, with 1.2% strain and 6 K temperature hysteresis, has been found in single crystalline Ni[sub 52]Mn[sub 24]Ga[sub 24]. The deformation can be enhanced more than three times, up to 4.0% shrinkage with a bias field 1.2 T applied along the measurement direction, or changed to 1.5% expansion by the 1.2 T applied perpendicular to the measurement direction. For achieving a large deformation, the magnetic field exhibits a more evident contribution than an external stress on this material. These characteristics can be attributed to the low level of internal stress and the preferential orientation of the martensitic variants. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Effects of aggregate size and shape on monotonic shear behaviour of unreinforced and geogrid-reinforced aggregate interfaces were systematically investigated through direct shear tests. Five different grades of angular aggregates and five kinds of rounded aggregates with identical particle size distribution were selected as test materials. Experiment results revealed the coupling effects of particle shape and aperture ratio (AS/D50), defined as the ratio of geogrid aperture size (AS) to the average particle size of aggregate (D50), on the shear behaviour of the unreinforced and reinforced interfaces. The peak shear stress, shear displacements corresponding to peak shear stress and residual shear stress, as well as maximum dilation of aggregate–geogrid interfaces at each AS/D50 were greater than those of glass beads–geogrid interfaces. The largest interface shear strength coefficient of aggregate–geogrid interfaces was achieved at AS/D50 = 2.55, and the optimum reinforcement of glass beads–geogrid interfaces appeared at AS/D50 = 5.05. The shear strength decreased more after the peak when the value of AS/D50 was relatively small, and the post-peak strength reduction of aggregate–geogrid interfaces was more pronounced. A generalised stress-dilatancy relationship was proposed, which introduced a variable dilatancy index (ζ) that reflected the effects of aperture ratio and particle shape. [ABSTRACT FROM AUTHOR]

The stress-strain relationship for uniaxial compression of a metal hollow sphere material in large strains is obtained using a simplified model for the spheres' deformation within a 3D block assuming a hexagonal packing pattern. The yield strength and material strain hardening are obtained as functions of the relative density in two characteristic loading directions. The expression for the stress-strain relationship consisting of quadratic and linear terms with respect to the relative density is linked to the partitioning of the deformation energy during compression. The theoretical predictions are compared with limited test results on mild steel hollow sphere material and finite element simulation results obtained by our group. [ABSTRACT FROM AUTHOR]

High Mn content added to Mg-6Zn-0.3Ca extruded alloy remarkably refined dynamically recrystallized (DRXed) grains, and enhanced tensile and compressive strengths without sacrificing ductility. The large amount of fine Mn precipitates of homogenized alloy that formed effectively restricted new grain growth during the subsequent extrusion and generated ultra-fine DRXed grains. The ultra-fine DRXed grains and large amount of precipitates essentially enhanced the strength and improved the anisotropy of alloy. The Mg-Mn-x ternary systems that potentially formed ultra-fine grains were also discussed. [ABSTRACT FROM AUTHOR]

In the present work, 1 at% Y was added to Ti-50.7at%Ni alloy to prepare Ti-50.2Ni-1Y alloy and the effects of rare earth Y addition on the microstructure and martensitic transformation behavior of Ti-50.7at%Ni alloy was investigated by optical microscope, scanning electronic microscope (SEM) X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The results show the microstructure of Ti-50.2Ni-1Y alloy is different with that of Ti-50.7at.%Ni alloy, and its microstructure consists of B19′martensite and the Y-rich phase, which may be YNi phase. One-step martensitic transformation occurs in Ti-50.2Ni-1Y ternary alloy. The phase transformation temperatures increase rapidly with Y addition, and the increase of Ms is about 85°C. [ABSTRACT FROM AUTHOR]

In this paper, we investigate mixed bicycle flow using the multi-value cellular automata (CA) model. Two types of bicycles with different maximum speed are considered in the system. The system of mixed bicycles is investigated under both deterministic and stochastic regimes. It is shown under the deterministic case that there appear multiple states both in congested flow and free flow regions. Analytical analysis is carried out and is in good agreement with the simulation results. Under the stochastic case, the multiple states effect disappears only when both slow and fast bicycles are randomized. Spacetime plots are presented to show the evolution of mixed bicycle flow. [ABSTRACT FROM AUTHOR]

Many patients who require allogeneic hematopoietic stem cell transplantation (allo-HSCT) lack a human leukocyte antigen (HLA)-matched donor. Here, we report a protocol for haploidentical allo-HSCT that combines granulocyte-colony stimulating factor primed bone marrow (G-BM) and peripheral blood stem cells (PBSC) without in vitro T-cell depletion (TCD). In this study, 171 patients, including 86 in high-risk group, underwent transplantation from haploidentical family donors. All patients achieved sustained, full donor chimerism. One hundred and eleven patients were alive in remission at a median of 682 (253–1502) days. The cumulative incidence of grade III–IV acute graft-versus-host disease (GVHD) was 23% and that of extensive chronic GVHD, 47%; these were not influenced by HLA disparity. Patients younger than 15 years had less grade III–IV acute GVHD than older patients (P=0.044). The 2-year probability of relapse was 12% for standard-risk disease and 39% for high-risk disease. The 2-year probability of leukemia-free survival (LFS) was 68% for standard-risk patients and 42% for high-risk patients (P=0.0009). Grade III–IV acute GVHD was associated with better LFS (P=0.0017). The results require confirmation and show that G-BM combined with PBSC from haploidentical family donors, without in vitro TCD, may be used as a good source of stem cells for allo-HSCT.Bone Marrow Transplantation (2006) 38, 291–297. doi:10.1038/sj.bmt.1705445 [ABSTRACT FROM AUTHOR]

Objective: To investigate the value of inflammation,coagulation and nutrition markers in predicting the failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation for treatment of periprosthetic joint infection(PJI). Methods: A retrospective study was conducted on 70 patients who undertook prosthesis removal and antibiotic-loaded bone cement spacer implantation due to PJI from June 2016 to October 2020 in the Department of Orthopedics,Henan Provincial People's Hospital. There were 28 males and 42 females,aged (65.5±11.9) years (range: 37 to 88 years). Patients were divided into two groups as the successful group and the failed group depended on whether reinfection occurred after prosthesis removal and antibiotic-loaded bone cement spacer implantation at the last follow up. Patient demographics,laboratory values (C-reactive protein (CRP),erythrocyte sedimentation rate (ESR),ESR and CRP ratio (ESR/CRP),white blood cell count(WBC),platelet count(PLT),hemoglobin(HB),total lymphocyte count(TLC),albumin、fibrinogen(FIB),CRP and albumin ratio (CAR),prognostic nutritional index(PNI)),and reinfection rates were assessed. Comparison between groups was conducted by the independent sample t test or χ 2 test. Receiver operating characteristic (ROC) curve was plotted,and the area under the curve (AUC),optimal diagnostic threshold,sensitivity,and specificity were analyzed to predict the failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation. Results: All patients were followed up for at least two years,and the follow-up time was (38.4±15.2) months (range: 24 to 66 months). Fifteen patients suffered failure after prosthesis removal and antibiotic-loaded bone cement spacer implantation,while the other 55 patients succeeded. The overall failure rate of prosthesis removal and antibiotic-loaded bone cement spacer implantation in PJI treatment was 21.4%. Level of preoperative CRP ((35.9±16.2)mg/L),PLT ((280.0±104.0)×10 9 /L) and CAR (1.3±0.8) in successful group were lower than CRP ((71.7±47.3)mg/L),PLT ((364.7±119.3)×10 9 /L) and CAR (2.5±2.0) in failed group (all P <0.05).Whereas,level of preoperative ESR/CRP (3.3±3.1), Albumin ((35.3±5.2)g/L) and PNI (43.6±6.2) in successful group were higher than ESR/CRP (1.6±1.4),Albumin ((31.3±4.8)g/L) and PNI (39.2±15.1) in failed group (all P <0.05). AUC of ROC curve,optimal threshold value,sensitivity and specificity of CRP,ESR/CRP, PLT, Albumin,CAR and PNI for the predicting failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation were 0.776(95% CI :0.660 to 0.867),35.4 mg/L,86.7%,67.3%;0.725(95% CI :0.605 to 0.825),1.0,60.0%,78.2%;0.713(95% CI :0.593 to 0.815),253,93.3%,47.3%;0.721(95% CI :0.601 to 0.822),35.7,93.3%,49.1%;0.772(95% CI :0.656 to 0.863),1.1,86.7%,67.3%;0.706(95% CI :0.585 to 0.809),45.7,100%,41.8% respectively. Conclusion: In patients with PJI,CRP>35.4,ESR/CRP≤1.0 and CAR>1.1 could predict the failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation.

With characteristics of high infectivity, diverse transmission routes and high variation, norovirus is the main pathogen of sporadic cases and outbreaks of acute gastroenteritis, resulting in a serious disease burden. This paper summarizes the latest progress in epidemiological research of norovirus infection from aspects of disease burden caused by acute gastroenteritis, virus variation and predominant strains, prevention and control measures, and immunization and vaccine development.

Objective: To evaluate the application of real-time RT-PCR and semi-nested RT-PCR in the detection of norovirus in oysters and analyzing the genetic characteristics of the isolates. Methods: Real-time fluorescent RT-PCR and semi-nested RT-PCR were used to detect norovirus GⅠ/GⅡ in fresh oysters collected from the markets in Beijing from November 2014 to October 2015. The detection rate of the parallel test was also analyzed. In addition, the reliability of semi-nested RT-PCR was evaluated by agreement rate and consistency test (Kappa value). The positive products of norovirus GⅠ/GⅡ capsid protein region gene by semi-nested RT-PCR were sequenced. Software BioEdit 7.0.9.0 was used for sequence alignment, and software Mega 6.0 was used to construct the evolutionary tree. Results: In 72 samples, the detection rate of norovirus was 31.94% (23/72) by real-time RT-PCR, 38.89% (28/72) by semi-nested RT-PCR and 48.61% (35/72) by parallel test. The coincidence rate of the two methods was 73.61%, a moderate degree (Kappa value =0.43). A total of 13 norovirus strains were successfully sequenced, and 11 strains (7 GⅡ.17 strains, 2 GⅡ. 4 Sydney&#95; 2012 strains, 1 GⅡ. 1 strain and 1 GⅡ. 21 strain) were obtained from norovirus positive samples by two RT-PCR methods, two strains (1 GⅡ. 17 strain and 1 GⅡ. 3 strain) were obtained from real-time RT-PCR negative samples which were positive for norovirus by semi-nested RT-PCR. The similarity between these strains and reference strains from diarrhea patients, environmental sewage, and shellfish products were 84.4% - 100.0%. Conclusions: The parallel test of norovirus in oysters by two RT-PCR methods can improve the detection rate and detect more genotypes. Norovirus strains in oysters were highly homologous with reference strains from diarrheal patients, environmental sewage, and shellfish products. Therefore, surveillance, prevention and control for norovirus should be carried out in people who have frequent contacts with oysters and related environments.

Objective: To study the prevalence of Norovirus infection among kitchen workers in Beijing, and the contamination status of Norovirus in catering companies and train station. Methods: A cross-sectional survey was conducted to collect anal swab specimens and environmental specimens from catering companies in 16 districts of Beijing and in 3 big train stations. Norovirus nucleic acid was detected by fluorescence quantitative PCR. The contamination status of Norovirus in the environment and the asymptomatic infection status of kitchen workers was analyzed in this study. Results: A total of 650 catering companies were investigated. 1 302 anal swabs or stool specimens and 2 600 environmental swabs were collected and tested. Among the 644 catering companies out of train stations, 1 290 anal swabs or stool specimens and 2 576 environmental swabs were collected and tested. The asymptomatic infection rate of Norovirus was 0.85% (11/1 290) among kitchen workers of the catering companies out of the train stations, while the positive rate of norovirus contamination in the environment was 0.04% (1/2 576). Norovirus was not detected in the specimens collected from the kitchen workers and the environment of the catering companies in train stations. Conclusion: During the non-epidemic season of Norovirus in 2019, the infection rate of Norovirus among kitchen workers in Beijing is low, and the environment is contaminated by Norovirus.

Contaminations of SARS-CoV-2 have been found for many times in imported cold chain aquatic products and their packaging materials in China. The purpose of this paper is to analyze the contamination status, sources and transmission risks of SARS-CoV-2 in imported cold chain aquatic products, and try to put forward relevant suggestions and strategies in order to provide evidence for the prevention and control of SARS-CoV-2 infection.

Objective: To explore the mechanism of nuclear factor-kappa B (NF-κB), phosphatidylinositol 3-kinase (PI3K)/protein kinase B(PKB/Akt) and mitogen-activated protein kinase (MAPK) signaling pathways after intervention of advanced glycosylation end products (AGEs) in peripheral blood mononuclear cells (PBMCs) and osteoblasts (OB) in rats, so as to provide certain experimental basis and theoretical basis for further research on the clinical treatment of periodontal tissue inflammation caused by diabetes mellitus., Methods: AGEs were prepared, PBMCs and OB were isolated and cultured in vitro . CCK-8 was used to detect the cell viability intervened by different concentrations and time of AGEs. Western blot and qRT-PCR were used to detect the expression changes of genes related to NF-κB, PI3K/PKB and MAPK signaling pathways., Results: OB and PBMCs were successfully isolated and cultured in vitro . The activity of PBMCs and OB cells was significantly correlated with the concentration, time and interaction of AGEs. With the increase of AGEs concentration and time, the activity of PBMCs and OB cells significantly decreased ( P < 0.001). AGEs stimulation significantly increased the expression of NF-κB in PBMCs and the contents of tumor necrosis factor α(TNF-α), interleukin-1β(IL-1β) ( P < 0.01). TNF-α, IL-1β levels were significantly reduced after inhibition of NF-κB pathway ( P < 0.01). NF-κB p65, JNK, and p38 phosphorylated and non-phosphorylated proteins increased significantly after AGEs stimulation of OB ( P < 0.05). The phosphorylated protein expression of IκB was significantly increased, while the expression of non-phosphorylated protein was decreased ( P < 0.01).The expressions of NF-κB p65, JNK, and IκB were significantly increased at the mRNA levels, and the expressions of IκB mRNA were significantly decreased ( P < 0.05). There was no difference in the expression of Akt in either phosphorylated or non-phosphorylated proteins or at the mRNA level ( P >0.05). With the addition of MAPK signaling pathway inhibitors, the phosphorylation and non-phosphorylated protein expressions of NF-κB p65, p38 and JNK were significantly reduced, and the phosphorylated protein of IκB was significantly decreased and the non-phosphorylated protein was significantly increased compared with the group with AGEs alone ( P < 0.05). The results of qRT-PCR showed that the expression of IκB increased significantly after the addition of the JNK pathway blocker ( P < 0.05), and the expression of NF-κB p65, p38 and JNK decreased, but the difference was not significant ( P >0.05). While NF-κB p65, p38 and JNK were significantly decreased and IκB was significantly increased in the AGEs group after the addition of the p38 pathway blocker ( P < 0.05). At this time, there was still no significant change in the expression of Akt at the protein level and mRNA level ( P >0.05)., Conclusion: AGEs inhibit the proliferation of PBMCs and OB, and the NF-κB and MAPK pathways are likely involved in regulating this process, but not the PI3K/PKB pathway.

Objective: To explore the flora characteristics and differences of esophageal tissues between elderly esophageal squamous cell carcinoma (ESCC) patients and young and middle-aged ESCC patients, so as to assist in studying the potential biomarkers of elderly ESCC patients. Methods: In this study, a retrospective study was adopted. 72 ESCC patients diagnosed in Taihe Hospital, Shiyan City, Hubei Province from July 2018 to July 2019 were selected, including 49 patients in the elderly group (≥ 60 years old, 40 males and 9 females), 23 patients in the young and middle-aged group (<60 years old, 21 males and 2 females). In the same period, 20 healthy persons without abnormal gastroscopy in endoscopy center were selected as the control group (aged 35-78 years old, median age 57 years old, 16 males and 4 females). The genomic DNA was extracted from the affected esophageal tissues of patients with ESCC and the middle esophageal samples of the control group. The V4 hypervariable region of bacterial 16SrRNA gene sequence was amplified. Illumina HiSeq sequencing technology was adopted. The flora characteristics of elderly, young and middle-aged ESCC patients was compared and analyzed. QIIME and Rstudio software were used to analyze the sequence data, and nonparametric Kruskal-Wallis test or Wilcoxon rank sum test were used for statistical methods. Results: Shannon index [5.17 (4.53, 5.95) vs. 4.79 (3.74, 5.97)], Simpson index [0.94 (0.91, 0.96) vs. 0.92 (0.83, 0.96)] and Chao1 index [343.55 (259.76, 570.59) vs. 329.16 (268.88, 648.00)] were similar in flora of two groups, and there was no significant difference ( Z =-0.791, -1.057, -0.380, all P >0.05). There was no significant difference in β-diversity between the elderly group and the young and middle-aged group (PC1=19.14%, PC2=6.95%, P PC1 =0.67, P PC2 =0.42). At the phyla level, the top 5 phyla in abundance were as follows: Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria and Fusobacteria in the young and middle-aged group, while the top 5 phyla in abundance were as follows: Firmicutes, Bacteroidetes, Proteobacteria, Fusobacteria and Actinobacteria in the elderly group; the significant difference between the two groups was Fusobacteria ( Q =0.596, P< 0.05). At the genus level, the top 5 genera in the young and middle-aged group in abundance were as follows: Prevotella, Bacteroides, Streptococcus, Selenomonas and Veillonella. In the elderly group, Prevotella, Bacteroides, Streptococcus, Selenomonas and Haemophilus were the top 5 in abundance, and there were significant difference in Fusobacterium between the two groups ( Q =0.938, P< 0.05). PICRUSt function prediction showed that the abundance of Aminoacyl.tRNA.biosynthesis, Nucleotide.excision.repair, RNA.polymerase, Ribosome, Clavulanic.acid.biosynthesis, Photosynthesis and Photosynthesis. proteins in the elderly group were lower than those in the young and middle-aged group (all Q =0.734, P< 0.05). Conclusion: There is no significant difference in α-diversity and β-diversity between elderly ESCC patients and young and middle-aged patients, but the abundance of Fusobacterium flora increased.

Purpose: This study set out to probe into the effect and mechanism of miR-144-3p on radiosensitivity of gastric cancer (GC) cells., Methods: Cancer tissue and paracancerous tissue of GC patients admitted to our hospital were collected, their miR-144-3p expression was tested, GC cells were transfected, and survival and biological behavior of those cells under radiation were detected., Results: After detection, miR-144-3p expression was down-regulated in GC tissue, while ZEB1 was up-regulated. There was no remarkable difference in the survival fraction of cells in each group before receiving radiation, but that of tumor cells decreased obviously (p < 0.05) after radiation exposure. Survival fraction of cells overexpressing miR-144-3p or silencing ZEB1 decreased more obviously, while the inhibition of miR-144-3p or overexpressing ZEB1 was weaker. Biological behavior of cells under 6 Gy radiation was detected. It was found that miR-144-3p overexpression or silencing ZEB1 dramatically inhibited the proliferation activity of GC cells under 6 Gy radiation, increased the levels of pro-apoptotic Bax and caspase-3 proteins (p < 0.05) and decreased the anti-apoptotic protein Bcl-2 level (p < 0.05), resulting in an increase in the apoptosis rate of cells. miR-144-3p was confirmed to be ZEB1 targeting site by dual luciferase report. Moreover, rescue experiments prove that it can increase the radiosensitivity of GC cells by regulating ZEB1 expression., Conclusion: miR-144-3p expression was down-regulated in GC, and it can increase the radiosensitivity of those cells by inhibiting ZEB1 expression.