Formation mechanism of inherent spatial heterogeneity of microstructure and mechanical properties of NiTi SMA prepared by laser directed energy deposition

Ni51Ti49 at.%bulk was additively manufactured by laser-directed energy deposition(DED)to reveal the microstructure evolution,phase distribution,and mechanical properties.It is found that the localized remelting,reheating,and heat accumulation during DED leads to the spatial heterogeneous distribution of columnar crystal and equiaxed crystal,a gradient distribution of Ni4Ti3 precipitates along the building direction,and preferential formation of Ni4Ti3 precipitates in the columnar zone.The austenite transformation finish temperature(Af)varies from-12.65℃(Z=33 mm)to 60.35℃(Z=10 mm),corresponding to tensile yield strength(σ0.2)changed from 120±30 MPa to 570±20 MPa,and functional properties changed from shape memory effect to superelasticity at room temperature.The sample in the Z=20.4 mm height has the best plasticity of 9.6%and the best recoverable strain of 4.2%.This work provided insights and guidelines for the spatial characterization of DEDed NiTi.

超高度近视有晶状体眼后房屈光晶状体植入术后拱高的影响因素分析

目的:探讨超高度近视有晶状体眼后房屈光晶状体植入术后拱高的影响因素。方法:回顾性病例研究。选取2019-01/2021-01于我院行PC-PRL植入术的超高度近视患者40例77眼。术后随访至少2a,评估裸眼视力(UCVA)、最佳矫正视力(BCVA)和中央前房深度(ACD)、前房容积(ACV)、前房角(ACA)、晶状体厚度及术后拱高等眼前节参数,分析术后拱高的影响因素。结果:PC-PRL植入术后纳入患者UCVA和BCVA均较术前显著改善(P<0.001),术后2a平均安全指数(术后BCVA/术前BCVA)为1.36±0.32,平均有效指数(术后UCVA/术前BCVA)为1.23±0.31。术后2a拱高与术前ACD、术前ACV、术前ACA及晶状体厚度均具有一定的相关性,其中术前ACV和晶状体厚度对术后2a拱高具有显著影响。结论:超高度近视PC-PRL植入术安全有效,可显著改善视力,术前ACV和晶状体厚度是影响术后拱高的重要因素。

妊娠合并糖尿病对产妇剖宫产后产褥期感染病原菌特点及耐药性的影响

目的探讨妊娠合并糖尿病对产妇剖宫产后产褥期感染病原菌特点及耐药性的影响。方法回顾性分析2018年5月—2021年7月贵阳市妇幼保健院79例剖宫产后产褥期感染患者的临床资料,根据妊娠期是否合并糖尿病分为研究组47例(妊娠合并糖尿病)和对照组32例(妊娠未合并糖尿病)。比较两组患者的一般资料、不同感染部位病原菌特点、产褥期感染病原菌分布情况、产褥期感染的主要革兰阳性菌(金黄色葡萄球菌、表皮葡萄糖菌)和主要革兰阴性菌(大肠埃希菌、铜绿假单胞菌)对常见抗菌药物的耐药性。结果两组孕周、喂养方式、感染部位、年龄、产程比较,差异无统计学意义(P>0.05);79例剖宫产后产褥期感染患者中共分离检出94株菌株(对照组41株、研究组53株),两组病原菌感染部位比较,差异无统计学意义(P>0.05);94株菌株中革兰阳性菌50株(53.19%),革兰阴性菌32株(34.04%),真菌12株(12.77%),两组产褥期感染的革兰阳性菌、真菌数比较,差异无统计学意义(P>0.05),研究组产褥期感染的革兰阴性菌多于对照组(P<0.05);研究组产褥期感染的革兰阴性菌中大肠埃希菌多于对照组(P<0.05);两组产褥期感染的金黄色葡萄球菌对氨苄青霉素、氧氟沙星、头孢拉定、环丙沙星的耐药性均>50%,研究组产褥期感染的金黄色葡萄球菌对头孢噻肟的耐药性高于对照组(P<0.05);两组产褥期感染的大肠埃希菌对氨苄青霉素、头孢他啶、庆大霉素的耐药性均>50%,研究组产褥期感染的铜绿假单胞菌对哌拉西林/他唑巴坦、亚胺培南的耐药性高于对照组(P<0.05)。结论妊娠合并糖尿病对产妇剖宫产后产褥期感染病原菌特点及耐药性具有一定的影响,其可增加革兰阴性感染率,也可提高金黄色葡萄球菌与铜绿假单胞菌的耐药性。

A comparative study on the transplantation of different concentrations of human umbilical mesenchymal cells into diabetic rats

AIM: To observe the effects of intravitreal injections of different concentrations of human umbilical mesenchymal stem cells on retinopathy in rats with diabetes mellitus.METHODS: Healthy and adult male Sprague-Dawley(SD) rats were randomly assigned to a normal control group(group A), a diabetic retinopathy(DR) blank control group(group B), a high-concentration transplantation group(group C), a low-concentration transplantation group(group D) and a placebo transplantation group(group E). The expression of nerve growth factor(NGF)protein in the retinal layers was detected by immunohistochemical staining at 2, 4, 6 and 8wk.RESULTS: The expression of NGF was positive in group A and most positive in the retinal ganglion cell layer. In groups B and E, the expression of NGF was positive 2wk after transplantation and showed an increase in all layers. However, the level of expression had decreased in all layers at 4wk and was significantly reduced at 8wk. In groups C and D, the expression of NGF had increased at 2wk and continued to increase up to 8wk. The level of expression in group C was much higher than that in group D.CONCLUSION: DR can be improved by intravitreal injection of human umbilical mesenchymal stem cells.High concentrations of human umbilical mesenchymal stem cells confer a better protective effect on DR than low concentrations.

Electrochemical properties of powder-pressed Pb-Ag-PbO_(2) anodes

Pb?Ag?PbO2 composite anodes with different mass fractions(1%,2%,3%,4%and 5%)ofβ-PbO2 were prepared by powder-pressed(PP)method.The galvanostatic polarization curves,Tafel curves and anodic polarization curves were tested in sulfuric acid solution.The morphologies and phase compositions of the anodic layers formed after galvanostatic polarization were investigated by using scanning electron microscope(SEM)and X-ray diffractometer(XRD),respectively.The results showed thatβ-PbO2 can improve the electrocatalytic activity of anodic oxide.The anode containing 3%β-PbO2 had the lowest overpotential of oxygen evolution reaction(OER)and the best corrosion resistance.The morphologies of the anode surfaces were gradually transformed from regular crystals to amorphous ones as the content ofβ-PbO2 increased in anodes.

Revisiting the role of delta-1-pyrroline-5-carboxylate synthetase in drought-tolerant crop breeding

The delta-1-pyrroline-5-carboxylate synthetase(P5CS)gene exercises a protective function in stressed plants.However,the relationship between proline accumulation caused by P5CS and abiotic stress tolerance in plants is not always clear,as P5CS overexpression has been reported to repress plant growth under normal conditions in several reports.We re-evaluated the role of P5CS in drought-tolerant rice breeding by expressing the AtP5CS1 and feedback-inhibition-removed AtP5CS1(AtP5CS1^(F128A))genes under the regulation of an ABA-inducible promoter to avoid the potential side effects of P5CS overexpression under normal conditions.ABA-inducible AtP5CS1 and AtP5CS1^(F128A) increased seedling growth in a nutrient solution(under osmotic stress)and grain yield in pot plants.However,the evidently deleterious effects of AtP5CS1 on grain quality,tiller number,and grain yield in the field indicated the unsuitability of P5CS for drought-tolerance breeding.

Preparation of Rice Seedling-raising Substrate with Spent Mushroom Substrate of Pleurotus eryngii

This study aimed to explore the effect of fermented spent mushroom substrate(SMS) of Pleurotus eryngii as a basic material on rice seedling-raising substrate. The physical and chemical indices of the SMS indicated that the fermented SMS was fully composted and was very suitable for preparing rice seedling-raising substrate. The fermented SMS effectively regulated the bulk density, total porosity, aeration porosity and water-holding porosity of rice seedling-raising substrate. With the increased addition amount of fermented SMS, the bulk density of rice seedling-raising substrate was decreased, but the total porosity, aeration porosity and water-holding porosity were increased. Compared with those in the substrates of 100% soil and 100% SMS,the height, chlorophyll content, 100-shoot dry weight, 100-root dry weight, root activity, nitrogen content, phosphorus content and potassium content of rice seedlings in the substrate composed of spent mushroom substrate of P. eryngii and soil were higher.The quality of rice seedlings in the substrate composed of 20% soil and 80% SMS was best, followed by that in the substrate composed of 30% soil and 70% SMS.

Effects of Phosphate Fertilizer on Yield and Quality of Eleocharis dulcis

The effects of different application levels and species of phosphatic fertilizer on Eleocharis dulcis were studied. The results showed that the growth stage of Eleocharis dulcis was not significantly influenced by different levels of phosphatic fertilizer application, with phosphorus level in 195-375 kg/hm^2. With increasing of the phosphorus level, starch and total soluble sugar accumulated, but the yield was not improved significantly. The analysis on the economic benefits showed that the best phosphorus level was 195 kg/hm^2. The growth stage and yield of Eleocharis dulcis were not considerably influenced by different proportions of calcium-magnesia phosphate fertilizer and ammonium dihydrogen phosphate. With increasing of ammonium dihydrogen phosphate, big-fruit rate of Eleocharis dulcis kept growing, but the accumulations of starch and total soluble sugar were decreasing.

Development of Sichuan Brocade with Imitating Embroidery Effect Based on Free-Floats Interlacing Weave

Owing to the diversity of consumer’s demand, the traditional Sichuan brocade products have to be innovated in order to survive in a competitive environment. Since the construction of traditional Sichuan brocade was composed of basic-weave, the surface of the fabric shows a regular interweaving planar texture and is difficult to represent a three-dimensional effect. Inspired by embroidery handcraft, this paper attempts to achieve the embroidery-like effect on the fabric through the jacquard process. Based on the multi-backed structure of traditional Sichuan brocade, we adopted the zoned-combination design mode and added extra free-floats interlacing weave in the area where we want to show the embroidered effect and arranged the interlacing points by referring to the feature of the pattern. As a result, designed Sichuan brocades by this method are capable of displaying embroidered effect with high realism and three-dimensionality. This approach improves the artistic effect of the traditional Sichuan brocade and provides a technical reference for further texture design of jacquard fabrics.

Diversity and Bioactivity of Cultivable Animal Fecal Actinobacteria

Microbial symbionts play important roles in food digestion and absorption, immunity, pathogens resistance, and health maintaining of their hosts by coevolution. To provide new sources for discovering new leader compounds of drugs, the diversity and bioactivities of cultivable actinobacteria from animal feces have been studied. 31 species of animal fecal samples were collected fromYunnanWildAnimalPark. The purified cultures of actinobacteria were isolated from these samples by using 5 media. The 16S rRNA gene sequences of 528 selected strains were determined, the phylogenetic analysis was carried out, and anti-microbial and anti-tumor activities were determined. 35 genera (including a new genus, Enteractinococcus) of actinobacteria from the 31 species of animal feces were identified. Some strains had high anti-tumor and antimicrobial activities. More than 50 secondary metabolites were isolated and identified, a novel bioactive macrolactam polyketide glycoside, Sannastatin, was found. Nine fecal streptomycete strains were fermented respectively, blended to the microbial manure, and used to prophylaxis and treatment of soil-borne disease of notoginseng in field. The incidence rate of the disease was lower 81% than agricultural chemicals. Fecal actinobacteria, a possibility as a new source for discovering drug leader, agricultural chemicals and other industry products, will be discussed.

Pyrotinib and chrysin synergistically potentiate autophagy in HER2-positive breast cancer

Human epidermal growth factor receptor 2(HER2)-positive breast cancer(BC)has been the most challenging subtype of BC,consisting of 20%of BC with an apparent correlation with poor prognosis.Despite that pyrotinib,a new HER2 inhibitor,has led to dramatic improvements in prognosis,the efficacy of pyrotinib monotherapy remains largely restricted due to its acquired resistance.Therefore,identifying a new potential antitumor drug in combination with pyrotinib to amplify therapeutic efficacy is a pressing necessity.Here,we reported a novel combination of pyrotinib with chrysin and explored its antitumor efficacy and the underlying mechanism in HER2-positive BC.We determined that pyrotinib combined with chrysin yielded a potent synergistic effect to induce more evident cell cycle arrest,inhibit the proliferation of BT-474 and SK-BR-3 BC cells,and repress in vivo tumor growth in xenograft mice models.This may be attributed to enhanced autophagy induced by endoplasmic reticulum stress.Furthermore,the combined treatment of pyrotinib and chrysin induced ubiquitination and glucose-6-phosphate dehydrogenase(G6PD)degradation by upregulating zinc finger and BTB/POZ domain-containing family protein 16(ZBTB16)in tumorigenesis of BC.Mechanistically,we identified that miR-16-5p was a potential upstream regulator of ZBTB16,and it showed a significant inverse correlation with ZBTB16.Inhibition of miR-16-5p overexpression by restoring ZBTB16 significantly potentiated the overall antitumor efficacy of pyrotinib combined with chrysin against HER2-positive BC.Together,these findings demonstrate that the combined treatment of pyrotinib and chrysin enhances autophagy in HER2-positive BC through an unrecognized miR-16-5p/ZBTB16/G6PD axis.

Optimal Gestational Weight Gain for Women with Gestational Diabetes Mellitus—China,2011–2021

Summary What is already known about this topic?Joint effects of gestational weight gain(GWG)and hyperglycemia on adverse pregnancy outcomes suggest that lower optimal GWG is optimal for women with gestational diabetes mellitus(GDM).However,there is still a lack of guidelines.What is added by this report?Optimal weekly GWG range after diagnosis of GDM for underweight,normal-weight,overweight,and obese women was 0.37–0.56 kg/week,0.26–0.48 kg/week,0.19–0.32 kg/week,and 0.12–0.23 kg/week,respectively.What are the implications for public health practice?The findings may be used to inform prenatal counseling regarding optimal gestational weight gain for women with gestational diabetes mellitus,and suggest the need for weight gain management.

Weekly Weight Gain in Women with Gestational Diabetes Mellitus and Neonatal Birth Weight - China, 2011–2021

What is already known about this topic?Elevated gestational weight gain(GWG)during pregnancy among women diagnosed with gestational diabetes mellitus(GDM)is correlated with an increased instance of large for gestational age(LGA)and macrosomia.However,it remains uncertain whether managing weekly GWG following a GDM diagnosis positively impacts fetal birth weight.What is added by this report?Our study found that GWG following GDM diagnosis correlates positively with the risk of LGA and macrosomia among all body mass index(BMI)subgroups,especially for overweight and obese women.What are the implications for public health practice?The results of this research highlight the importance of enforcing a more stringent regulation on GWG on a weekly basis for overweight and obese women diagnosed with GDM,particularly when considering neonatal growth.

Alterations of brain local functional connectivity in amnestic mild cognitive impairment

Background:Resting-state functional magnetic resonance imaging studies using a regional homogeneity(ReHo)method have reported that amnestic mild cognitive impairment(aMCI)was associated with abnormalities in local functional connectivity.However,their results were not conclusive.Methods:Seed-based d Mapping was used to conduct a coordinate-based meta-analysis to identify consistent ReHo alterations in aMCI.Results:We identified 10 studies with 11 datasets suitable for inclusion,including 378 patients with aMCI and 435 healthy controls.This meta-analysis identified significant ReHo alterations in patients with aMCI relative to healthy controls,mainly within the default mode network(DMN)(bilateral posterior cingulate cortex[PCC],right angular gyrus,bilateral middle temporal gyri,and left parahippocampal gyrus/hippocampus),executive control network(right superior parietal lobule and dorsolateral prefrontal cortex),visual network(right lingual gyrus and left middle occipital gyrus),and sensorimotor network(right paracentral lobule/supplementary motor area,right postcentral gyrus and left posterior insula).Significant heterogeneity of ReHo alterations in the bilateral PCC,left parahippocampal gyrus/hippocampus,and right superior parietal lobule/angular gyrus was observed.Exploratory meta-regression analyses indicated that general cognitive function,gender distribution,age,and education level partially contributed to this heterogeneity.Conclusions:This study provides provisional evidence that aMCI is associated with abnormal ReHo within the DMN,executive control network,visual network,and sensorimotor network.These local functional connectivity alterations suggest coexistence of functional deficits and compensation in these networks.These findings contribute to the modeling of brain functional connectomes and to a better understanding of the neural substrates of aMCI.Confounding factors merit much attention and warrant future investigations.

A high-sensitivity H2S gas sensor based on optimized ZnO-ZnS nano-heterojunction sensing material

This paper reports a high-performance H2S gas sensing material that is made of ZnO nanowires(NWs)modified by an optimal amount of ZnS to form nano-hete rojunctions.Compared with the intrinsic ZnONWs,the three differently modified nano-heterostructure material ZnO-ZnS-x(x=5,10,15)shows significant improvement in sensing performance to H2S at the working temperatures of 100-400℃,especially in the low temperature range(<300℃).The chemiresistive sensor with ZnO-ZnS-10 sensingmaterial exhibits the largest response signal to H2S among all the other ZnO-ZnS-x(x=5,10,15,20)sensors.Its response signal to 5 ppm H2S at 150℃is about 2.7 times to that of the ZnO-NWs sensor.Besides,the ZnO-ZnS-10 sensor also features satisfactory selectivity and repeatability at 150℃.With the technical advantage attributed to the reduction of the redesigned band gap at the interface between ZnO and ZnS,the ZnO-ZnS hete ro structure sensor rather than the traditional ZnO-NWs sensor can be used for high-sensitivity application at low working temperature.

Radial Anisotropy in the Crust beneath the Northeastern Tibetan Plateau from Ambient Noise Tomography

Through analysis of Rayleigh wave and Love wave Green＇s functions estimated from ambient noise tomography, we obtain radial anisotropy and shear wave velocity structure beneath the northeastern Tibetan Plateau. With two hundred and twenty three broadband seismic stations deployed by China Earthquake Administration, a collaborative seismic experiment of northern Tibet（ACSENT） experiment and northeastern Tibet seismic（NETS） experiment provide the unprecedented opportunity to resolve the spatial distribution of the radial anisotropy within the crust of the northeastern Tibetan Plateau. Discrepancies between Love（sh） and Rayleigh（sv） wave velocities show complex anisotropic patterns associated with the dynamic processes of the collision between the Indian and Eurasian plates：（1） In the upper crust, V（sv）〉V（sh） anisotropy is dominant throughout the study area which probably reflects fossil microcracks induced by the uplift, folding and erosion geodynamic processes;（2） in the middle crust, V（sh）〉V（sv） observed beneath the Songpan-Ganzi terrane and the northwestern Qilian orogen correlates well with a mid-crustal low velocity zone（LVZ）;（3） at depths deeper than 40 km, V（sh）〉V（sv） is still found in the Songpan-Ganzi terrane. This anisotropy could be caused by the sub-horizontal alignment of anisotropic minerals that has followed the collision between India and Eurasia. However, the northwestern Qilian orogen is associated with V（sv）〉V（sh） anisotropy which may be related to the vertically aligned seismic anisotropic minerals caused by the crustal thickening.

Monitoring of SiC MOSFET Junction Temperature with On-state Voltage at High Currents

A junction temperature monitoring method has been presented based on the on-state voltage at high currents.With a simplified physical model,this method mapped the relationship between junction temperature and on-state voltage.The tough calibration and signal sensing issues are solved.Verified by body-diode voltage detecting method,the presented method shows a good performance and high accuracy,in the meantime,it would not change the modulation strategy and topology of the converter.

Absolute control of helicity at the C-termini in quinoline oligoamide foldamers by chiral oxazolylaniline moieties

Absolute one-handed chiral quinoline tetramers andoctamers containing different oxazolylanilines at the C-terminus have been synthesized.The absolute one-handed sense and diastereomeric excess values were valued by^1H NMR.X-ray crystal diffractionand CD studies reveal that the S-oxazolylaniline always induces a P-handed helicity and the absolute helicity is driven by the stable three-center hydrogen bonding between protons in the amide and N atoms in oxazolylaniline and adjacent quinoline ring.CPL investigations demonstrated that S-CQn-a-d are CPL active and its g(lum)values are dependent on its length.Interestingly,the sizes of the substituents in the chiral centers are different,howeve r,they exert no effect on the dissymmetric factors g(abs)and g(lum)of quinoline oligoamide foldamers.

Accurate Evaluation of Cooling System Capability of Three-phase IGBT-based Inverter

In this paper,an offline evaluation method for the cooling capability of three-phase insulated-gate bipolar transistor(IGBT)inverters is presented,which can better emulate real working conditions.With a properly designed sudden-stop control sequence,the conventional junction temperature monitoring method at a low current is used to calculate the junction temperature before the sudden stop of an inverter.This can solve the challenging switching loss calculation issue in conventional methods.Finally,the feasibility,control sequence,and electrical behaviors of the proposed method are validated through experimental tests.

Online Junction Temperature Measurement of Double-sided Cooling IGBT Power Module through On-state Voltage with High Current

The aim of this study is to achieve online monitoring of the junction temperature of double-sided-cooling insulated gate bipolar transistor(IGBT)power modules by using the on-state voltage under a high current to maximize the utilization of IGBT power chips.Online junction temperature measurement plays an important role in improving the reliability of the inverter with IGBT,increasing the power density of the motor controller of electric vehicles,and reducing the cost of electric vehicles.