Cr涂层对Zr-4合金蠕变行为的影响

报道化学气相沉积Cr涂层对Zr-4合金蠕变性能的影响以及Cr涂层在服役温度下的热稳定性。利用扫描电镜、电子探针显微分析和电子背散射衍射研究样品的显微组织。结果表明:样品Zr-4基体中晶粒呈等轴状,存在明显的<0001>//ND织构。蠕变后涂层样品的Zr-4合金基体中亚晶界数量明显低于无涂层样品Zr-4合金基体中亚晶界数量,表明Cr涂层显著降低了Zr-4合金基体在蠕变过程中承载的应力,提高了合金的抗蠕变性能。Cr涂层在长时间扩散实验中保持高稳定性。涂层在高蠕变应力下(350℃时不小于157 MPa,400℃时不小于137 MPa)出现裂纹。系统总结蠕变断裂的数据,得到了关于稳态蠕变速率与蠕变断裂时间的Monkman-Grant关系式。

乙炔选择加氢反应中碳化钯的动态精细调控: 气氛和氧化锌助剂的作用

碳化钯通常被认为是乙炔选择加氢反应中原位生成的活性相,其生成有助于抑制次表面非选择性的氢化钯物种,从而实现高选择性乙炔加氢制乙烯的目标.次表面上碳化钯和氢化钯物种之间的竞争很大程度上决定了乙炔加氢反应的选择性.然而,由于实际反应环境的复杂性,反应环境下的两种物种之间的动态转化过程和竞争关系尚不清晰.特别是,反应环境(比如氢气组分)对碳化钯物种的调控机制仍不明确,也使得对碳化钯活性物种的精准调控变得困难.此外,氧化锌助剂作为乙炔选择加氢反应中最常用的助剂之一,存在典型的金属-氧化物界面相互作用,也会对渗碳过程产生重要影响.因此,从动态视角理解碳化钯物种的原位形成过程,对于精准设计和合成高性能乙炔选择加氢钯基催化剂具有重要的科学意义.近年来,先进原位表征光谱技术的不断发展使得从原子、分子层面理解原位过程机制成为可能.本文旨在通过先进的原位表征技术揭示乙炔选择加氢反应中碳化钯物种的动态生成过程,并进一步探究气氛环境、温度、助催化剂等参数对碳化钯物种的动态调控机制,从而为高性能乙炔选择加氢催化剂的精准设计和合成提供有力支撑.原位研究结果表明,在氢气升温还原条件下,空气焙烧后新鲜催化剂中氧化钯相首先转变为氢化钯相;随着还原温度升高,氢化钯相的含氢量逐渐降低.当切换至乙炔选择加氢反应原料气时,氢化钯相迅速分解为金属钯,并随着恒温碳化时间的延长,烃类裂解产生的碳原子逐渐渗入钯的体相,最终形成稳定的碳化钯活性相.通过移除乙炔加氢反应原料气氛中的氢气,考察了反应气中的氢气组分对碳化钯形成的调控机制.实验发现,在仅有乙炔和乙烯存在时,碳化过程仍能发生;而引入少量氢气(体积分数2.2%)后,碳化程度显著增强,C/Pd原子比从0.136提升至0.154.相变机理研究表明,氢气的引入促进了氢化钯物种的形成,并通过晶格扩张作用促进渗碳过程.此外,还研究了氧化锌助剂对原位渗碳过程的影响,揭示了氧化锌助剂对碳化钯的抑制作用.结合原位CO吸附漫反射红外光谱、准原位X射线光电子能谱分析发现,低温氢气还原下Pd-ZnO界面作用促进了微量表面PdZn合金的生成,从而抑制了碳的渗入.这种现象在不含氢气的碳化气氛中尤为显著,碳含量降低一个数量级(C/Pd原子比仅为0.019).在此基础上,通过调节反应条件,实现了对碳化钯物种碳含量的精准调控,并与反应活性关联,揭示了碳化钯含量与乙炔选择加氢反应活性之间的线性关系.电子结构表征和同位素实验进一步表明,Pd-C的电子相互作用促进了向Pd中心原子的电子转移,从而提高了氢气的活化解离能力和乙炔加氢反应活性.综上,本工作原位解析了碳化钯的动态形成过程,阐明了氢气辅助插碳和ZnO抑制插碳的微观机制,实现了碳化钯活性物种的精准调控,揭示了碳化程度与反应活性的线性关系,为高性能乙炔选择加氢催化剂设计提供了参考.

细胞外基质蛋白ABI3BP抗水疱性口炎病毒初步作用研究

目的探讨细胞外基质蛋白ABI3BP对水疱性口炎病毒(vesicular stomatitis virus,VSV)基因组复制和先天免疫信号通路的影响。方法在人皮肤成纤维细胞BJ-5ta中转染小干扰RNA(siRNA)敲低ABI3BP基因,建立ABI3BP基因缺失的VSV-GFP病毒感染细胞模型。通过鬼笔环肽细胞免疫荧光实验,检测敲低ABI3BP后细胞内肌动蛋白(F-actin)形态结构的变化。在ABI3BP基因缺失的VSV-GFP病毒感染细胞模型上,利用RT-qPCR方法检测细胞中病毒mRNA水平的变化。利用免疫印迹法(Western blotting)检测IRF3和TBK1磷酸化水平的变化。结果成功建立敲减ABI3BP基因的VSV-GFP感染的细胞模型。鬼笔环肽细胞免疫荧光染色表明,敲减ABI3BP基因后,细胞内F-actin的表达发生结构重排。采用不同剂量的病毒感染细胞,与对照组相比,ABI3BP敲低细胞中基因拷贝数分别增加2.5~3.5倍(P<0.01)和2.2~4倍(P<0.01),VSV-GFP病毒蛋白表达水平显著上调;在ABI3BP基因敲低的细胞模型上,VSV-GFP病毒感染导致Ⅰ型干扰素免疫通路关键免疫分子p-IRF3和p-TBK1蛋白磷酸化水平明显下调。结论本研究表明细胞外基质蛋白ABI3BP对维持细胞内F-actin纤维网状结构具有重要作用。ABI3BP缺失促进RNA病毒的复制,ABI3BP是I型干扰素通路激活的重要调控分子。

Evaluating two stages of silicone-containing arylene resin oxidation via experiment and molecular simulation

Silicon-containing aryl acetylene resin(PSA)is a new type of high-temperature resistant resin with excellent oxidation resistance,whereas antioxidant reaction mechanism of PSA resin under ultra-high temperatures still remains unclear.Herein,the oxidation behavior and mechanisms of PSA resin are systematically investigated combining kinetic analysis and Reax FF molecular dynamics(MD)simulations.Thermogravimetric analysis indicates that the oxidation process of PSA resin undergoes two main steps:oxidative mass gain and oxidative degradation.The distributed activation energy model(DAEM)is employed for describing oxidation processes and the best-fit one is obtained using genetic algorithms and differential evolution.DAEM model demonstrates that the oxidative weight gain stage is dominated by two virtual reactants and the oxidative degradation stage consists of three virtual reactants.Correspondingly,the observation of MD reaction pathways indicates that oxygen oxidation of unsaturated structures occurs in the initial stage,which results in the formation of PSA resin oxides.Furthermore,cracked pieces react with O_(2)to generate CO and other chemicals in the second step.The resin matrix's great antioxidation resilience is illustrated by the formation of SiO_(2).The analysis based on MD simulations exhibits an efficient computational proof with the experiments and DAEM methods.Based on the results,a two-stage reaction mechanism is proposed,which provides important theoretical support for the subsequent study of the oxidation behavior of silica-based resins.

ZmbZIP27 regulates nitrogen-mediated leaf angle by modulating lignin deposition in maize

In grain crops such as maize(Zea mays),leaf angle(LA)is a key agronomic trait affecting light interception and thus planting density and yield.Nitrogen(N)affects LA in plants,but we lack a good understanding of how N regulates LA.Here,we report that N deficiency enhanced lignin deposition in the ligular region of maize seedlings.In situ hybridization showed that the bZIP transcription factor gene ZmbZIP27 is mainly expressed in the phloem of maize vascular bundles.Under N-sufficient conditions,transgenic maize overexpressing ZmbZIP27 showed significantly smaller LA compared with wild type(WT).By contrast,zmbzip27_(ems)mutant showed larger LA under both N-deficient and N-sufficient conditions compared with WT.Overexpression of ZmbZIP27 enhanced lignin deposition in the ligular region of maize in the field.We further demonstrated that ZmbZIP27 could directly bind the promoters of the microRNA genes ZmMIR528a and ZmMIR528b and negatively regulate the expression levels of ZmmiR528.ZmmiR528 knockdown transgenic maize displayed erect architecture in the field by increasing lignin content in the ligular region of maize.Taken together,these results indicate that ZmbZIP27 regulates N-mediated LA size by regulating the expression of ZmmiR528 and modulating lignin deposition in maize.

Impacts of information about COVID-19 on pig farmers'production willingness and behavior:Evidence from China

This paper examines the impacts of information about COVID-19 on pig farmers'production willingness by using endorsement experiments and follow-up surveys conducted in 2020 and 2021 in China.Our results show that,first,farmers were less willing to scale up production when they received information about COVID-19.The information in 2020 that the second wave of COVID-19 might occur without a vaccine reduced farmers'willingness to scale up by 13.4%,while the information in 2021 that COVID-19 might continue to spread despite the introduction of vaccine reduced farmers'willingness by 4.4%.Second,farmers whose production was affected by COVID-19 were considerably less willing to scale up,given the access to COVID-19 information.Third,farmers'production willingness can predict their actual production behavior.

Quality-adjusted time without symptoms or toxicity analysis of haploidentical-related donor vs.identical sibling donor hematopoietic stem cell transplantation in acute myeloid leukemia

Objective:We aimed to compare the quality-adjusted time without symptoms or toxicity(Q-TWiST)in acute myeloid leukemia(AML)patients who received haploidentical-related donor(HID)and identical sibling donor(ISD)hematopoietic stem cell transplantation(HSCT).Methods:Five clinical health states were defined:toxicity(TOX),acute graft-versus-host disease(GVHD),chronic GVHD(cGVHD),time without symptoms and toxicity(TWiST)and relapse(REL).The equation used in this study was as follows:Q-TWiST=UTOX×TOX+UTWiST×TWiST+UREL×REL+UaGVHD×aGVHD+UcGVHD×cGVHD.Results:A total of 239 AML patients were enrolled.We established a mathematical model,i.e.,Q-TWiST HID HSCT>Q-TWiST ISD HSCT,to explore the range of utility coefficients satisfying the inequality.Based on the raw data,the utility coefficient is equivalent to the following inequality:10.57067UTOX-46.27733UREL+105.9374+3.388078UaGVHD-210.8198UcGVHD>0.The model showed that when UTOX,UREL,and UaGVHD were within the range of 0-1,as well as when UcGVHD was within the range of 0-0.569,the inequality Q-TWiST HID HSCT>Q-TWiST ISD HSCT was valid.According to the results of the ChiCTR1800016972 study,the median coefficients of TOX,acute GVHD(aGVHD),and cGVHD were 0.56(0.41-0.76),0.56(0.47-0.72),and 0.54(0.37-0.79),respectively.We selected a series of specific examples of the coefficients,i.e.,UTOX=0.5,UREL=0.05,UaGVHD-0.5,and UcGVHD-0.5.The Q-TWiST values of ISD and HID HSCT were 896 and 900 d,respectively(P=0.470).Conclusions:We first observed that Q-TWiST was comparable between AML patients receiving HID HSCT and those receiving ISD HSCT.

Zinc finger protein 296 promotes hepatocellular carcinoma progression via intervening interaction between macrophages and B cells

Objective:Hepatocellular carcinoma(HCC)is a prevalent malignancy with poor survival.Different cell types in the tumor microenvironment participate in the tumorigenesis and progression of HCC.This study aimed to analyze the immune microenvironment of HCC and its relationship with clinical outcomes.Methods:We analyzed HCC RNA-seq for cell type identification and prognosis by estimating relative subsets of RNA transcripts using CIBERSORTx.The interaction between B cells and macrophages in HCC was analyzed using a Hepa1-6 orthotopic transplantation mouse model and flow cytometry.The effect of Zinc finger protein 296(ZNF296)on the interaction of B cells and macrophages was verified using human HCC tissues analyzed through western blot,quantitative real-time polymerase chain reaction(qPCR),and multiplex immunofluorescence.A comparative analysis of immune cells associated with HCC prognosis was performed using RNA-seq data from The Cancer Genome Atlas(TCGA),bulk multimodal data,and single-cell transcriptomic data from existing HCC single-cell transcriptomic data employing the Single Cell Inferred Site Specific Omics Resource for Tumor Microenvironments(SCISSOR).Results:Liver hepatocellular carcinoma(LIHC)RNA-seq analysis of TCGA showed that high eosinophil infiltration promoted HCC progression.The proportion of B cells correlated with that of macrophages(r=−0.24)and affected the infiltration and programmed death ligand 1(PD-L1)expression of macrophages in HCC.ZNF296 may participate in the interaction between B cells and macrophages to accelerate the HCC progression by regulating PAFAH1B3 and H2AFX.Moreover,ZNF296 expression positively correlated with LAG3(r=0.27)and CTLA4(r=0.31)expression levels.Among the immune cell phenotypes related to survival and death identified by SCISSOR analysis,T cells correlated with an excellent prognosis of HCC.The normal function of liver and dendritic cells was also associated with a good prognosis in HCC.Conclusions:This study analyzed the interaction of the immune microenvironment with HCC prognosis,identifying ZNF296 as a promising diagnostic and therapeutic target for HCC.

Impacts of angiotensin II on retinal artery changes in apolipoprotein E deficient mice

AIM:To investigate the impacts of angiotensin II(Ang II)on retinal artery changes in apolipoprotein E deficient(apoE^(-/-))mice.METHODS:ApoE^(-/-)male mice were infused by minipumps with Ang II at 1000 ng/kg·min(Ang II group)or saline(control group)for 28d.They were underwent ophthalmic fundus examination on day 0,14,and 28 of infusion.Histopathologic examination,ribonucleic acid(RNA)sequencing and local Ang II measurement of retinas were conducted.RESULTS:Ophthalmic fundus examination showed Ang II infusion promoted the formation of retinal arterial aneurysm-like lesions on day 28.Optical coherence tomography revealed the ganglion cell and inner plexiform layer(GCIPL)thickness in the control group was significantly thinner than that in Ang II group(P<0.001).Hematoxylin-eosin staining demonstrated diffused swelling of GCIPL layer and its disordered structure in Ang II group.Transmission electron microscopy showed Ang II infusion caused aggravation of atherosclerotic lesions,including increased swelling,roughness,disorganization of the retinal vasculature,and vacuoles formation.RNA-sequencing and gene ontology enrichment analysis demonstrated that the structure and function of cellular membrane might be disturbed and visual function might be compromised by Ang II.The local level of Ang II was higher in Ang II infusion group but did not show significant differences compared to the control group(P=0.086).CONCLUSION:Ang II infusion promotes the formation of retinal arterial aneurysm-like lesions in apoE^(-/-)mice,causing aggravation of atherosclerotic lesions,more severe disorganization of the retinal vasculature and disturbance of the cellular membrane.

Non-contact wide-field viewing system-assisted scleral buckling surgery for retinal detachment in silicone oilfilled eyes

AIM:To evaluate scleral buckling(SB)surgery using a noncontact wide-field viewing system and 23-gauge intraocular illumination for the treatment of rhegmatogenous retinal detachment in silicone oil(SO)-filled eyes.METHODS:Totally 9 patients(9 eyes)with retinal detachment in SO-filled eyes were retrospectively analyzed.All patients underwent non-contact wide-field viewing system-assisted buckling surgery with 23-gauge intraocular illumination.SO was removed at an appropriate time based on recovery.The patients were followed up for at least 3mo after SO removal.Retinal reattachment,complications,visual acuity and intraocular pressure(IOP)before and after surgery were observed.RESULTS:Patients were followed up for a mean of 8.22mo(3-22mo)after SO removal.All patients had retinal reattachment.At the final follow-up,visual acuity showed improvement for 8 patients,and no change for 1 patient.The IOP was high in 3 patients before surgery,but it stabilized after treatment;it was not affected in the other patients.None of the patients had infections,hemorrhage,anterior ischemia,or any other complication.CONCLUSION:This new non-contact wide-field viewing system-assisted SB surgery with 23-gauge intraocular illumination is effective and safe for retinal detachment in SO-filled eyes.

Higher-order topological Anderson insulator on the Sierpiński lattice

Disorder effects on topological materials in integer dimensions have been extensively explored in recent years. However, its influence on topological systems in fractional dimensions remains unclear. Here, we investigate the disorder effects on a fractal system constructed on the Sierpiński lattice in fractional dimensions. The system supports the second-order topological insulator phase characterized by a quantized quadrupole moment and the normal insulator phase. We find that the second-order topological insulator phase on the Sierpiński lattice is robust against weak disorder but suppressed by strong disorder. Most interestingly, we find that disorder can transform the normal insulator phase to the second-order topological insulator phase with an emergent quantized quadrupole moment. Finally, the disorder-induced phase is further confirmed by calculating the energy spectrum and the corresponding probability distributions.

Optimal timing for the oral administration of DaCheng-Qi decoction based on the pharmacokinetic and pharmacodynamic targeting of the pancreas in rats with acute pancreatitis

AIM To identify the optimal oral dosing time of Da-Cheng-Qi decoction(DCQD) in rats with acute pancreatitis(AP) based on the pharmacokinetic and pharmacodynamic parameters.METHODS First, 24 male Sprague-Dawley rats were divided into a sham-operated group [NG(a)] and three model groups [4 h G(a), 12 h G(a) and 24 h G(a)]. The NG(a) and model groups were administered DCQD(10 g/kg.BW) intragastrically at 4 h, 4 h, 12 h and 24 h, respectively, after AP models induced by 3% sodium taurocholate. Plasma samples were collected from the tails at 10 min, 20 min, 40 min, 1 h, 2 h, 4 h, 8 h, 12 h and 24 h after a single dosing with DCQD. Plasma and pancreatic tissue concentrations of the major components of DCQD were determined by high-performance liquid chromatography tandem mass spectroscopy. The pharmacokinetic parameters and serum amylase were detected and compared. Second, rats were divided into a sham-operated group [NG(b)] and three treatment groups [4 h G(b), 12 h G(b) and 24 h G(b)] with three corresponding control groups [MG(b)s]. Blood and pancreatic tissues were collected 24 h after a single dosing with DCQD. Serum amylase, inflammatory cytokines and pathological scores of pancreatic tissues were detected and compared.RESULTS The concentrations of emodin, naringin, honokiol, naringenin, aloe-emodin, chrysophanol and rheochrysidin in the 12 h G(a) group were higher than those in the 4 h G(a) group in the pancreatic tissues(P < 0.05). The area under the plasma concentration-time curve from time 0 to the time of the last measurable concentration values(AUC0→t) for rhein, chrysophanol, magnolol and naringin in the 12 h G(a) group were larger than those in the 4 h G(a) or 24 h G(a) groups. The 12 h G(a) group had a higher Cmax than the other two model groups. The IL-10 levels in the 12 h G(b) and 24 h G(b) groups were higher than in the MG(b)s(96.55 ± 7.84 vs 77.46 ± 7.42, 251.22 ± 16.15 vs 99.72 ± 4.7 respectively, P < 0.05), while in the 24 h G(b) group, the IL-10 level was higher than in the other two treatment groups(251.22 ± 16.15 vs 154.41 ± 12.09/96.55 ± 7.84, P < 0.05). The IL-6 levels displayed a decrease in the 4 h G(b) and 12 h G(b) groups compared to theMG(b)s(89.99 ± 4.61 vs 147.91 ± 4.36, 90.82 ± 5.34 vs 171.44 ± 13.43, P < 0.05). CONCLUSION Late-time dosing may have higher concentrations of the most major components of DCQD, with better pharmacokinetics and pharmacodynamics of antiinflammation than early-time dosing, which showed the late time to be the optimal dosing time of DCQD for AP.

Optimal dosing time of Dachengqi decoction for protection of extrapancreatic organs in rats with experimental acute pancreatitis

BACKGROUND Acute pancreatitis(AP)is a pancreatic inflammatory disorder that is commonly complicated by extrapancreatic organ dysfunction.Dachengqi decoction(DCQD)has a potential role in protecting the extrapancreatic organs,but the optimal oral administration time remains unclear.AIM To screen the appropriate oral administration time of DCQD for the protection of extrapancreatic organs based on the pharmacokinetics and pharmacodynamics of AP rats.METHODS This study consisted of two parts.In the first part,24 rats were divided into a sham-operated group and three model groups.The four groups were intragastrically administered with DCQD(10 g/kg)at 4 h,4 h,12 h,and 24 h postoperatively,respectively.Tail vein blood was taken at nine time points after administration,and then the rats were euthanized and the extrapancreatic organ tissues were immediately collected.Finally,the concentrations of the major DCQD components in all samples were detected.In the second part,84 rats were divided into a sham-operated group,as well as 4 h,12 h,and 24 h treatment groups and corresponding control groups(4 h,12 h,and 24 h control groups).Rats in the treatment groups were intragastrically administered with DCQD(10 g/kg)at 4 h,12 h,and 24 h postoperatively,respectively,and rats in the control groups were administered with normal saline at the same time points.Then,six rats from each group were euthanized at 4 h and 24 h after administration.Serum amylase and inflammatory mediators,and pathological scores of extrapancreatic organ tissues were evaluated.RESULTS For part one,the pharmacokinetic parameters(C max,T max,T 1/2,and AUC 0→t)of the major DCQD components and the tissue distribution of most DCQD components were better when administering DCQD at the later(12 h and 24 h)time points.For part two,delayed administration of DCQD resulted in lower IL-6 and amylase levels and relatively higher IL-10 levels,and pathological injury of extrapancreatic organ tissues was slightly less at 4 h after administration,while the results were similar between the treatment and corresponding control groups at 24 h after administration.CONCLUSION Delayed administration of DCQD might reduce pancreatic exocrine secretions and ameliorate pathological injury in the extrapancreatic organs of AP rats,demonstrating that the late time is the optimal dosing time.

基于Spring MVC的安全保护机制设计

随着信息技术的不断发展,Web技术应用越来越广泛。Web系统的安全性已成为程序员必须考虑的问题。为了确保Web应用的安全可靠,以Spring模型-视图-控制器(Model-View-Controller,MVC)框架为基础,分别从访问控制、身份认证和数据加密3个方面,设计一套安全保护机制,帮助程序员更好地保护Web系统的安全,有效防范各种常见的Web应用安全威胁。

保和丸治疗食滞胃肠证泄泻合并肠道菌群失调的网络药理学分析

背景网络药理学整合了药物、靶点、疾病等信息,能够高效地阐明中药多组分和疾病多靶点之间的潜在作用关系.然而在许多网络药理学研究中,往往只注重中药对疾病靶点的作用,而忽视肠道菌群对疾病靶点的作用.将肠道菌群纳入网络药理学的研究中,可为中药多成分-多靶点-多途径贡献了一种新思路.目的采用网络药理学方法,探讨保和丸治疗食滞胃肠证泄泻合并肠道菌群失调的可能分子机制.方法通过TCMSP、BATMAN-TCM等数据库,结合文献筛选出保和丸活性成分及相应靶点.通过GeneCards数据库检索食滞胃肠证泄泻、肠道菌群的相关靶点,Venny平台筛选活性成分与疾病的共同靶点.Cytoscape 3.9.1软件构建疾病-靶点-化合物网络,筛选药物靶点、肠道菌群靶点和疾病靶点相互作用的有效靶点.STRING数据库构建蛋白质-蛋白质相互作用(protein-protein interaction,PPI)网络.利用DAVID数据库对有效靶点进行基因本体(Gene Ontology,GO)功能分析及京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)通路富集分析.结果共收集549种化学成分,根据OB≥30%及DL≥0.18,共得到45个活性成分,包括槲皮素、皮素、汉黄芩素、山奈酚、柚皮素等.Venn图显示保和丸活性成分中对应259个可能蛋白靶点,与食滞胃肠证泄泻存在作用的靶点有34个,与肠道菌群存在作用的有66个,三者共同的靶点数为11个,其过氧化物合酶2(peroxide synthase 2,PTGS2)、肿瘤坏死因子(tumor necrosis factor,TNF)、肿瘤蛋白P53(oncoprotein P53,TP53)、细胞间粘附分子-1(intercellular adhesion molecule-1,ICM1)、白介素10(interleukin-10,IL-10)为关键靶点.GO功能富集分析得到121个生物过程,KEGG通路富集筛选得到49条通路,包括TNF信号通路、白介素17(interleukin-17,IL-17)信号通路、NF-κB信号通路等.结论通过网络药理学的初步筛选及预测,保和丸可能通过多途径、多靶点改善食滞胃肠证泄泻合并肠道菌群失调.

涂层厚度对镀铬锆合金界面结合力和力学性能的影响

研究镀铬锆合金(Zr-4)的拉伸失效行为。通过对拉伸过程的实时观察,研究涂层厚度对界面附着力的影响。使用有限元分析和剪切强度理论定量评估Cr涂层的界面附着力。此外,还研究镀铬样品的裂纹扩展行为。结果表明,随着涂层厚度的增加,界面剪切强度和界面黏附性能下降。然而,对基材的保护作用随着涂层厚度的增加而增加。此外,涂层与基体界面处裂纹扩展的路径也随着涂层厚度的增加而变化。较薄涂层界面处的裂纹很容易扩展到基体中,造成局部损伤。较厚涂层的裂纹更容易沿界面扩展,导致黏合剂失效。

Melatonin treatment alleviates chilling injury in mango fruit 'Keitt' by modulating proline metabolism under chilling stress

Mangoes often suffer from low temperature-induced chilling injury (CI) during postharvest cold storage.Therefore,advanced techniques are crucial and in high demand to solve the chilling stress of mango fruit for a higher value.This study addresses chilling stress modulation by investigating the effects of melatonin treatment on CI,proline metabolism,and related gene expressions of ‘Keitt’ mango during cold storage after dipped in 0 (control),0.1 (MT1),and 0.2 mmol L^(-1)(MT2) melatonin solution for 30 min.The results revealed that melatonin treatment in MT1 significantly reduced CI development and increased proline content in mango fruit during cold storage compared to the control.These changes were along with increases in the activity of critical enzymes as well as the expression of encoding genes involved in proline biosynthesis,such as pyrroline-5-carboxylate synthetase (P5CS),pyrroline-5-carboxylate reductase (P5CR),ornithine D-aminotransferase (OAT),P5CS2,P5CR2,and OAT3.Additionally,proline dehydrogenase (PDH) activity and the expression of the PDH3 gene associated with proline dehydrogenation were lower in MT1-treated mangoes than the controlled group.Thus,melatonin treatment has regulated proline metabolism resulting in the accumulation of proline,subsequently contributing to enhancing the chilling tolerance of‘Keitt’mango fruit.

Non-conventional peptides in plants:From gene regulation to crop improvement

Conventional peptides(CPs)and non-conventional peptides(NCPs)are generated from small open reading frames,but most CPs are derived from large precursors.NCPs,which are derived from sequences other than conventional open reading frames or annotated coding sequences regions,function in plant development and adaptation to stresses.Ribosome profiling,a technique for studying translational regulation,can be used to identify NCPs.Another new technique,peptidogenomics,which integrates mass spectrometry and genomics,is becoming more widely used for identifying plant NCPs.In recent years,numerous studies have investigated the roles in monocots and dicots of miRNA-derived peptides and upstream open reading frames,which have potential for improving agronomic traits.Investigating the biological functions of NCPs will advance molecular plant breeding by identifying regulators of plant growth and development.We present an overview of NCP identification methods and recent findings about NCP biological functions.

Tailoring topological corner states in photonic crystals by near-and far-field coupling effects

We explore the behaviors of optically coupled topological corner states in supercell arrays composed of photonic crystal rods,where each supercell is a second-order topological insulator.Our findings indicate that the coupled corner states possess nondegenerate eigenfrequencies at theΓpoint,with coupled dipole corner states excited resonantly by incident plane waves and displaying a polarization-independent characteristic.The resonance properties of coupled dipole corner states can be effectively modulated via evanescently near-field coupling,while multipole decomposition shows that they are primarily dominated by electric quadrupole moment and magnetic dipole moment.Furthermore,we demonstrate that these coupled corner states can form surface lattice resonances driven by diffractively far-field coupling,leading to a dramatic increase in the quality factor.This work introduces more optical approaches to tailoring photonic topological states,and holds potential applications in mid-infrared topological micro-nano devices.

Maturity-onset diabetes of the young type 10 caused by an Ala2Thr mutation of INS:A case report

Maturity-onset diabetes of the young 10 caused by the c.4G>A (p.Ala2Thr)mutation is extremely rare, with only two reported studies to date. Herein, wereport another case that differs from previous cases in phenotype.CASE SUMMARYThe proband developed diabetes at the age of 27 years, despite having a normalbody mass index (BMI). She exhibited partial impairment of islet function, testedpositive for islet antibodies, and required high doses of insulin. Her sister alsocarried the c.4G>A (p.Ala2Thr) mutation, and their mother was stronglysuspected to carry the mutated gene. Her sister developed diabetes around 40years of age and required high doses of insulin, while the mother was diagnosedin her 20s and was managed with oral hypoglycemic agents;neither of them wereobese.CONCLUSION p.Ala2Thr mutation carriers often experience relatively later onset and normalBMI. Treatment regimens vary between individuals.