Based on the observation data of daily average temperature,daily rainfall and sunshine duration from 2005 to 2024 from the national basic meteorological station and regional meteorological station in Jingning,as well ...Based on the observation data of daily average temperature,daily rainfall and sunshine duration from 2005 to 2024 from the national basic meteorological station and regional meteorological station in Jingning,as well as the data of tea yield and growth period,the first picking date and quality of Huiming tea in Jingning were evaluated by the analysis of physical and chemical indicators and climate quality index of Huiming tea.The results show that in the past two decades,the first picking date of Huiming tea showed a significant advancing trend.Climate warming led to an increase in≥0℃active accumulated temperature,thus advancing the first picking date.The climate quality index of tea was"very excellent"in most years,and the physical and chemical indicators were at the special grade.Tea yield was significantly correlated with multiple meteorological factors,especially closely related to sunshine duration in early February and≥5℃active accumulated temperature from February to April.展开更多
BACKGROUND Castleman disease is an uncommon nonclonal lymphoproliferative disorder,which frequently mimics both benign and malignant abnormalities in several regions.Depending on the number of lymph nodes or regions i...BACKGROUND Castleman disease is an uncommon nonclonal lymphoproliferative disorder,which frequently mimics both benign and malignant abnormalities in several regions.Depending on the number of lymph nodes or regions involved,Castleman disease(CD)varies in diagnosis,treatment and prognosis.It rarely occurs in the pancreas alone without any distinct clinical feature and tends to be confused with pancreatic paraganglioma(PGL),neuroendocrine tumors(NETs),and primary tumors,thus impeding proper diagnosis and treatment.CASE SUMMARY A 28-year-old woman presented with a lesion on the neck of the pancreas,detected by ultrasound during a health examination.Physical examination and laboratory findings were normal.The mass showed hypervascularity on enhanced computed tomography(CT),significantly increased 18F-fluorodeoxyglucose uptake on positron emission tomography(PET)/CT,and slightly increased somatostatin receptor(SSTR)expression on^(68)Ga-DOTATATE PET/CT,suggesting no distant metastases and subdiagnoses such as pancreatic PGL,NET,or primary tumor.Intraoperative pathology suggested lymphatic hyperplasia,and only simple tumor resection was performed.The patient was diagnosed with the hyaline vascular variant of CD,which was confirmed by postoperative immunohistochemistry.The patient was discharged successfully,and no recurrence was observed on regular review.CONCLUSION High glucose uptake and slightly elevated SSTR expression are potentially new diagnostic features of CD of the pancreas.展开更多
Superior strength and high-temperature performance make γ-TiAl vital for lightweight aero-engines. However, its inherent brittleness poses machining problems. This study employed Elliptical Ultrasonic Vibration Milli...Superior strength and high-temperature performance make γ-TiAl vital for lightweight aero-engines. However, its inherent brittleness poses machining problems. This study employed Elliptical Ultrasonic Vibration Milling (EUVM) to address these problems. Considering the influence of machining parameters on vibration patterns of EUVM, a separation time model was established to analyze the vibration evolutionary process, thereby instructing the cutting mechanism. On this basis, deep discussions regarding chip formation, cutting force, edge breakage, and subsurface layer deformation were conducted for EUVM and Conventional Milling (CM). Chip morphology showed the chip formation was rooted in the periodic brittle fracture. Local dimples proved that the thermal effect of high-speed cutting improved the plasticity of γ-TiAl. EUVM achieved a maximum 18.17% reduction in cutting force compared with CM. The force variation mechanism differed with changes in the cutting speed or the vibration amplitude, and its correlation with thermal softening, strain hardening, and vibratory cutting effects was analyzed. EUVM attained desirable edge breakage by achieving smaller fracture lengths. The fracture mechanisms of different phases were distinct, causing a surge in edge fracture size of γ-TiAl under microstructural differences. In terms of subsurface deformation, EUVM also showed strengthening effects. Noteworthy, the lamellar deformation patterns under the cutting removal state differed from the quasi-static, which was categorized by the orientation angles. Additionally, the electron backscattering diffraction provided details of the influence of microstructural difference on the orientation and the deformation of grains in the subsurface layer. The results demonstrate that EUVM is a promising machining method for γ-TiAl and guide further research and development of EUVM γ-TiAl.展开更多
Pre-harvest sprouting(PHS)describes the germination of physiologically mature grains in spikes prior to harvest in cereal crops.PHS could seriously decrease grain yield and quality,which makes it a major constraint to...Pre-harvest sprouting(PHS)describes the germination of physiologically mature grains in spikes prior to harvest in cereal crops.PHS could seriously decrease grain yield and quality,which makes it a major constraint to cereal production worldwide.A number of PHS-associated genes in cereals have been reported;however,the molecular mechanisms underlying PHS remain largely elusive.Here,we report a CRISPRCas9 mutant with severe PHS in a paddy field.The mutated gene OsMFT2 encodes a phosphatidylethanolamine-binding protein(PEBP).Intriguingly,the OsMFT1,in the same PEBP family,had the opposite effect in controlling rice PHS as does OsMFT2.Germination tests of seeds of chimeric protein-expressing plants revealed that the fourth exon conferred the antagonistic activity of OsMFT1 and OsMFT2 in rice PHS.Additionally,two lines of these plants showed elevated grain numbers per panicle,implying that chimeric protein has potential to significantly increase yield.Moreover,transcriptome analysis and genetic studies indicated that OsMFT1 and OsMFT2 performed opposing functions in rice PHS owing to three co-regulated genes that being contrastingly affected by OsMFT1 and OsMFT2.Overall,it seemed that the proper combination of PEBP family members could obtain optimal PHS resistance and high yield.展开更多
目的探讨微孔板法、实时荧光PCR熔解曲线技术(简称“熔解曲线法”)、多色巢式实时荧光定量PCR技术(简称“Xpert法”)和罗氏药物敏感性试验(L-J药敏试验,简称“比例法”)用于快速筛查耐多药结核病(MDR-TB)的临床价值。方法从医院信息系统...目的探讨微孔板法、实时荧光PCR熔解曲线技术(简称“熔解曲线法”)、多色巢式实时荧光定量PCR技术(简称“Xpert法”)和罗氏药物敏感性试验(L-J药敏试验,简称“比例法”)用于快速筛查耐多药结核病(MDR-TB)的临床价值。方法从医院信息系统(hospital information system,HIS)连续收集2014年7月至2018年3月重庆市公共卫生医疗救治中心收治的确诊为结核病,且具有微孔板法、比例法、熔解曲线法、Xpert法检测MTB对利福平、异烟肼耐药性诊断结果的2792例患者资料;其中微孔板法、比例法采用阳性分离菌株检测,熔解曲线法和Xpert法采用患者标本直接检测。纳入同时具有微孔板法和比例法耐药性检测结果的1488例患者作为研究对象,其中341例行微孔板法+比例法+Xpert法检测利福平耐药性,87例行微孔板法+比例法+熔解曲线法检测利福平耐药性,66例行微孔板法+比例法+熔解曲线法检测异烟肼耐药性。以比例法为标准,采用SPSS13.0软件分别计算微孔板法、熔解曲线法、Xpert法检测利福平和(或)异烟肼耐药性的敏感度、特异度、符合率、Kappa值等。结果以比例法为标准,微孔板法、Xpert法、熔解曲线法检测利福平耐药性的敏感度、特异度、阳性预测值、阴性预测值、符合率、Kappa值分别为97.2%(731/752)、96.9%(713/736)、96.9%(731/754)、97.1%(713/734)、97.0%(1444/1488)、0.94,97.2%(140/144)、94.9%(187/197)、93.3%(140/150)、97.9%(187/191)、95.9%(327/341)、0.92,97.1%(33/34)、84.9%(45/53)、80.5%(33/41)、97.8%(45/46)、89.7%(78/87)、0.79;微孔板法和熔解曲线法检测异烟肼耐药性的敏感度、特异度、阳性预测值、阴性预测值、符合率、Kappa值分别为94.8%(751/792)、95.7%(667/697)、96.3%(751/780)、94.2%(667/708)、97.9%(1418/1448)、0.91,97.3%(36/37)、86.2%(25/29)、90.0%(36/40)、96.2%(25/26)、92.4%(61/66)、0.84。结论微孔板法、熔解曲线法、Xpert法检测利福平和(或)异烟肼耐药性均具有较高的敏感度和特异度,适合快速筛查耐多药结核病;微孔板法还能获得各药物最低药物浓度,为临床用药剂量的选择提供参考依据。展开更多
Perovskite optoelectronic devices,capitalizing on the exceptional light-matter interaction and semiconductor properties of perovskite materials,have emerged as transformative platforms for energy conversion,informatio...Perovskite optoelectronic devices,capitalizing on the exceptional light-matter interaction and semiconductor properties of perovskite materials,have emerged as transformative platforms for energy conversion,information storage,and photonic technologies.While material innovations and device engineering breakthroughs have propelled remarkable advancements,persistent challenges in operational stability,scalable manufacturing,and batch reproducibility continue to hinder commercial implementation.Recently,molecular ferroelectrics(MOFEs),as a class of materials characterized by polar crystal structures and switchable spontaneous polarization(P_(s)),offer novel pathways to regulate high-efficiency and stable perovskite optoelectronic devices.Here,we systematically review the application of MOFEs into diverse perovskite optoelectronic systems,emphasizing the synergistic effect between P_(s)and optoelectronic properties.We analyze MOFEs-based photodetectors spanning self-powered,X-ray,and polarized-light detectors,detailing how P_(s)and synergistic physical effects optimize device performance.For photovoltaic applications,we elucidate polarizationdriven performance enhancement mechanisms in perovskite solar cells(PSCs),including built-in field amplification,defect passivation,and stability improvement.Furthermore,we envisage the emerging applications of MOFEs in optoelectronic fields such as non-volatile memory,neuromorphic computing,and optical communication.Overall,this review furnishes valuable insights into optoelectronics and future energy.展开更多
Sphingolipids are not only a pivotal component of membranes but also act as bioactive molecules.Cotton fiber is one of the longest plant cells and sphingolipids are closely associated with the development of cotton fi...Sphingolipids are not only a pivotal component of membranes but also act as bioactive molecules.Cotton fiber is one of the longest plant cells and sphingolipids are closely associated with the development of cotton fiber cells.However,their function in cotton fiber cell development and its action mechanism is unclear.Through cotton genetic transformation and chemistry biological approach,we identified the function and action mechanism of the glucosylceramide synthase gene GhGCS1 and its product glucosylceramide(GluCer)in cotton fiber growth.GhGCS1 was preferentially expressed at the stage of fiber elongation and localized in the endoplasmic reticulum.Overexpression of GhGCS1 promoted GluCer synthesis and fiber elongation,which was consistent with the exogenous application of GluCer(FA-C22)(containing very long-acyl-chain fatty acid)to cotton fiber in ovule culture system in vitro.Contrarily,suppressing GhGCS1 expression inhibited GluCer synthesis and fiber elongation,which was similar as the exogenous application of GluCer synthesis inhibitor,PDMP.Transcriptome analysis revealed that the fiber elongation regulated by GhGCS1 was associated with brassinosteroid(BR)synthesis and signaling related gene expression.Meanwhile,we detected the BL content of control and transgenic fiber cells.The BL content significantly increased and decreased in up-and down-regulated transgenic fibers when compared with control fibers,respectively.Furthermore,we found that PDMP treatment blocked BR synthesis and signal transduction,while exogenous application of GluCer could enhance BR synthesis and signaling.Overall,our results revealed that GhGCS1 and GluCer regulated cotton fiber elongation by influencing BR synthesis and signaling.Our study shed a novel insight on regulatory mechanism of cotton fiber elongation and provides theoretical support,genetic resources and novel transgenic materials for improvement of crop quality.展开更多
Under the current background of an information society,the digital transformation of enterprises has become a necessary means to enhance the competitiveness of enterprises.This article is based on the industrial Inter...Under the current background of an information society,the digital transformation of enterprises has become a necessary means to enhance the competitiveness of enterprises.This article is based on the industrial Internet platform,the digital planning and architecture of enterprises research.First,we analyze the current challenges of digital transformation and the development opportunities brought by the industrial Internet.Then,we propose a digital planning method based on the industrial Internet platform,which takes the full connectivity of people,machine and things and intelligent decision making as the core,takes data collection,processing,analysis and application as the main line,and finally forms the top-level design of the digital transformation of enterprises.At the same time,we also built an industrial Internet platform architecture model,including the previous end perception layer,network transmission layer,platform service layer,and application innovation layer for four levels,to support enterprises in innovative applications and decision support under the industrial Internet environment.Research shows that this kind of enterprise digital planning and architecture based on an industrial Internet platform can effectively promote enterprises to achieve business model innovation,system innovation,and strengthen the flexibility and agility of enterprises to respond to market changes.The results of this research not only have important theoretical and practical significance for guiding enterprises to carry out digital planning and build an industrial Internet platform,but also provide useful reference for relevant policy formulation.展开更多
This study presents a comprehensive mechanical analysis of P110S oil tubing subjected to thermal and chemical coupling effects,with particular attention to the presence of rectangular corrosion defects.Drawing on the ...This study presents a comprehensive mechanical analysis of P110S oil tubing subjected to thermal and chemical coupling effects,with particular attention to the presence of rectangular corrosion defects.Drawing on the material’s stress–strain constitutive behavior,thermal expansion coefficient,thermal conductivity,and electrochemical test data,the research incorporates geometric nonlinearities arising from large deformations induced by corrosion.A detailed three-dimensional finite element(FE)model of the corroded P110S tubing is developed to simulate its response under complex loading conditions.The proposed model is rigorously validated through full-scale burst experiments and analytical calculations based on theoretical formulations.Building upon this validation,the Extended Finite Element Method(XFEM)and a failure criterion grounded in damage evolution mechanics are applied to investigate the mechanical behavior of the tubing under the coupled influences of temperature,stress,and chemical corrosion.Special emphasis is placed on the role of rectangular corrosion features in determining failure mechanisms.To further elucidate the impact of multiple interacting parameters,a sensitivity analysis is performed by integrating grey correlation theory with simulation outcomes.Based on these findings,the study systematically explores the elastic–plastic deformation process,crack initiation and propagation behavior,and the burst failure response of tubing specimens with varying axial lengths and depths of corrosion.The proposed methodology provides a robust predictive framework for petroleum engineers to evaluate fracture pressure,diagnose failure modes,assess operational risks,and optimize production strategies.展开更多
Azulene-fused acenes demonstrate enhanced stability,unique aromaticity,and distinctive photophysical properties,rendering them significant in organic electronics.In the present study,we report a new type of nonalterna...Azulene-fused acenes demonstrate enhanced stability,unique aromaticity,and distinctive photophysical properties,rendering them significant in organic electronics.In the present study,we report a new type of nonalternant analogue of pentacene incorporating a non-terminal azulene unit.Aromaticity analyses reveal that the five-membered rings in this analogue exhibit antiaromatic.The extensive conjugated aryl substituents on the acene’s side shift the HOMO distributions from the naphthyl ring and metallacycle to the aryl groups,thereby narrowing the HOMO-LUMO energy gap and enhancing absorptions in the low-energy regions.Furthermore,these fused acenes readily react with base rather than acid,resulting in reversible base/acid stimuli responsiveness.展开更多
Semicrystalline polymers usually undergo multilevel microstructural evolutions with annealing and stretching processes,which is es-sential to tailor the physical properties of the polymer.Here,poly(butylene carbonate)...Semicrystalline polymers usually undergo multilevel microstructural evolutions with annealing and stretching processes,which is es-sential to tailor the physical properties of the polymer.Here,poly(butylene carbonate)(PBC)sheets were prepared via isothermal annealing and unidirectional pre-stretching processes,then the changes of PBC in crystallinity,mechanical properties,thermal properties and microscopic changes before and after annealing and stretching were measured,as well as the relationship between microstructure and macroscopic proper-ties before and after stretching.The strengthening mechanism of PBC was also described.It was demonstrated that shish-kabab structure emerged under the pre-stretching process.With the increase of the tensile ratio,the crystallinity,structure and mechanical properties are in-creased differently.Among them,the crystallinity and tensile strength after annealing-stretching treatment increased to 24.45%and 104.5 MPa,respectively,which were about 1.55 times and 3.4 times of those-without any treatment.展开更多
Epidemiological studies indicate that prostate cancer(PCa)is the second prevalent malignant tumor affecting men globally.Environmental pollution such as cigarette smoke is one of the important risk factors for the dev...Epidemiological studies indicate that prostate cancer(PCa)is the second prevalent malignant tumor affecting men globally.Environmental pollution such as cigarette smoke is one of the important risk factors for the development of prostate cancer.However,as one of the main carcinogens in cigarette smoke,the role of benzo[a]pyrene(BaP)in prostate cancer is still unclear.The current study aimed to investgate the impacts of BaP exposure on the progression of PCa towardmalignancy and the regulation of the immune microenvironment.We verified that BaP exposure can promote the proliferation,migration,and apoptosis of prostate cancer cells through in vitro experiments.We constructed a subcutaneous xenograft tumor model of BaP exposure mouse and found that can promote the proliferation of tumors in vivo.Organoids-driven by PCa patients showed higher growth rate under BaP exposure.Flow cytometric analysis demonstrated a remarkable decrease in CD4^(+)T and CD8^(+)T cell infiltration levels.Moreover,we identified four genes(Mdm2,Ar,Foxo1,Crebbp)were strongly associated with BaP exposure by combining mouse tumor RNA-seq and CTD database.Additionally,a nomogram integrating clinicopathological features was constructed to assess the prognosis of prostate cancer patients under BaP exposure.This study systematically proved that BaP exposure promotes malignant progression of PCa and suppresses the immune microenvironment,in which Mdm2,Ar,Foxo1,Crebbp may play a crucial role in inhibiting apoptosis.These findings offer novel insights into themechanisms via which BaP exposure contributes to PCa development.展开更多
目的探索中国宁夏人群中HOTAIR单核苷酸多态性与胃癌(gastric cancer, GC)易感性的相关性研究.方法挑选3个H O TA I R基因位点r s12826786(C>T),rs920778(C>T), RS4759314(A>G),对其多态性进行了基因分型;选取152名GC患者和30...目的探索中国宁夏人群中HOTAIR单核苷酸多态性与胃癌(gastric cancer, GC)易感性的相关性研究.方法挑选3个H O TA I R基因位点r s12826786(C>T),rs920778(C>T), RS4759314(A>G),对其多态性进行了基因分型;选取152名GC患者和307名健康对照者,按照年龄,体重,性别等因素相匹配,通过PCR与高通量TaqMan分析其单核苷酸多态性对于GC遗传易感性的影响.结果HOTAIRRs920778位点基因型TT在病例组和对照组中的频率分别为26.3%和24.7%,基因型C/T在两组中的频率分别为21.1%和31.3%,基因型CC在两组中的频率分别为52.6%和44.0%,该位点的TT基因型与GC的遗传易感性具有显著联系,结果具有统计学意义(P <0.05).Rs12826786和Rs4759314两个基因位点与GC发病危险关系的结果并无统计学意义(P>0.05).进一步的分层分析中发现Rs920778位点的单核苷酸多态性与男性,吸烟人群及肿瘤大小≥5 cm的GC患者的GC遗传易感性高度相关,而与患者的年龄因素,女性患者,非吸烟患者,患者的远处转移情况及GC家族史并无显著联系.结论中国宁夏人群中HOTAIR Rs920778位点单核苷酸多态性与GC的遗传易感性具有一定程度的联系.展开更多
The efficacy and applied value of endoscopic hematoma evacuation vs. external ventricular drainage (EVD) in the treatment of severe ventficular hemorrhage (IVH) were explored and compared.From Jan.2015 to Dec.2016,the...The efficacy and applied value of endoscopic hematoma evacuation vs. external ventricular drainage (EVD) in the treatment of severe ventficular hemorrhage (IVH) were explored and compared.From Jan.2015 to Dec.2016,the clinical data of 42 cases of IVH were retrospectively analyzed,including 18 patients undergoing endoscopic hematoma evacuation (group A),and 24patients receiving EVD (group B).The hematoma clearance rate was calculated by 3D Slicer software,and complications and outcomes were compared between the two groups.There were no significant differences in age,sex and Graeb score between groups A and B (P>0.05).The hematoma clearance rate was 70.81%±27.64% in group A and 48.72%±36.58% in group B with a statistically significant difference (P<0.05).The operative time in groups A and B was 72.45±25.26 min and 28.54±15.27min,respectively (P<0.05).The Glasgow Coma Scale (GCS) score increased from 9.28±2.72 at baseline to 11.83±2.91 at 1 week postoperatively in group A,and from 8.25±2.62 at baseline to 10.79±4.12 at 1 week postoperatively in group B (P<0.05).The length of hospital stay was 12.67±5.97 days in group A and 17.33±8.91 days in group B with a statistically significant difference (P<0.05).The GOS scores at 6 months after surgery were 3.83±1.12 in group A,and 2.75±1.23 in group B (P<0.05). These results suggested that endoscopic hematoma evacuation has an advantage of a higher hematoma clearance rate,fewer complications and better outcomes in the treatment of severe IVH,indicating it is a safe,effective and promising approach for severe IVH.展开更多
The Blade Integrated Disk(Blisk) is one of the key components in the aero-engine, it is generally manufactured by the multi-axis milling and almost 90% raw materials are removed. To avoid the full immersion of a cutte...The Blade Integrated Disk(Blisk) is one of the key components in the aero-engine, it is generally manufactured by the multi-axis milling and almost 90% raw materials are removed. To avoid the full immersion of a cutter in the rough machining of a blisk channel, the trochoidal milling is a promising strategy since it can keep a small immersion angle in the rough milling process while maintaining the high machining efficiency. However, while toolpaths are being planned for the trochoidal milling process, the conventional methods are mainly for the planar machining area with fixed tool orientations, which cannot be used for complex channels where the multi-axis machining should be employed. To this end, this paper presents a four-axis trochoidal toolpath planning method with a ball-end cutter, and thus the blisk channel can be machined efficiently.For this to happen, the trochoidal paths are planned in the parametric domain and then mapped into the physical domain, with tool orientations controlled by the quaternion interpolation method to have smooth tool movement along the toolpaths. Both geometric simulation and physical milling experiments of the proposed method have convincingly demonstrated the validation of the proposed method.展开更多
Hepatic encephalopathy(HE) is a severe neuropsychiatric syndrome that most commonly occurs in decompensated liver cirrhosis and incorporates a spectrumof manifestations that ranges from mild cognitive impairment to co...Hepatic encephalopathy(HE) is a severe neuropsychiatric syndrome that most commonly occurs in decompensated liver cirrhosis and incorporates a spectrumof manifestations that ranges from mild cognitive impairment to coma. Although the etiology of HE is not completely understood, it is believed that multiple underlying mechanisms are involved in the pathogenesis of HE, and one of the main factors is thought to be ammonia; however, the ammonia hypothesis in the pathogenesis of HE is incomplete. Recently, it has been increasingly demonstrated that inflammation, including systemic inflammation, neuroinflammation and endotoxemia, acts in concert with ammonia in the pathogenesis of HE in cirrhotic patients. Meanwhile, a good number of studies have found that current therapies for HE, such as lactulose, rifaximin, probiotics and the molecular adsorbent recirculating system, could inhibit different types of inflammation, thereby improving the neuropsychiatric manifestations and preventing the progression of HE in cirrhotic patients. The antiinflammatory effects of these current therapies provide a novel therapeutic approach for cirrhotic patients with HE. The purpose of this review is to describe the inflammatory mechanisms behind the etiology of HE in cirrhosis and discuss the current therapies that target the inflammatory pathogenesis of HE.展开更多
Owing to its outstanding mechanical properties,γ-TiAl is desirable materials for crossgeneration aero-engines.Nearly 70 years of exploration have made it into the initial application.However,the intrinsic brittleness...Owing to its outstanding mechanical properties,γ-TiAl is desirable materials for crossgeneration aero-engines.Nearly 70 years of exploration have made it into the initial application.However,the intrinsic brittleness ofγ-TiAl is still a critical obstacle to its large-scale applications.In this context,researchers have made many attempts to study the machinability ofγ-TiAl.At present,existing relevant reviews have mostly discussed the processing methods ofγ-TiAl.Hence,there is still a lack of a perspective on material properties to analyze the cutting mechanism.Herein,this paper provides the systematic review of such perspectives.Above all,the developmental process,phase transformation,and microstructural evolution ofγ-TiAl are discussed,as well as its deformation mechanism at quasi-static.These topics can provide a materials science foundation for the machining ofγ-TiAl.And then,the review focuses on the cutting mechanism and surface integrity ofγ-TiAl.Moreover,special attention is paid to the microscope deformation mechanism and surface defects evolution ofγ-TiAl during cutting.Finally,the review indicates that the highperformance machining technology ofγ-TiAl faces challenges and proposes potential future research directions.Solving the difficulties during machiningγ-TiAl aero-engine components will accelerate the development of new aero-engines.展开更多
Geometric error,mainly due to imperfect geometry and dimensions of machine components,is one of the major error sources of machine tools.Considering that geometric error has significant effects on the machining qualit...Geometric error,mainly due to imperfect geometry and dimensions of machine components,is one of the major error sources of machine tools.Considering that geometric error has significant effects on the machining quality of manufactured parts,it has been a popular topic for academic and industrial research for many years.A great deal of research work has been carried out since the 1970s for solving the problem and improving the machining accuracy.Researchers have studied how to measure,detect,model,identify,reduce,and compensate the geometric errors.This paper presents a thorough review of the latest research activities and gives an overview of the state of the art in understanding changes in machine tool performance due to geometric errors.Recent advances in measuring the geometrical errors of machine tools are summarized,and different kinds of error identification methods of translational axes and rotation axes are illustrated respectively.Besides,volumetric geometric error modeling,tracing,and compensation techniques for five-axis machine tools are emphatically introduced.Finally,research challenges in order to improve the volumetric accuracy of machine tools are also highlighted.展开更多
The Dachang tin-polymetallic district, Guangxi,China, is one of the largest tin ore fields in the world. Both cassiterite-sulfide and Zn–Cu skarn mineralization are hosted in the Mid-Upper Devonian carbonate-rich sed...The Dachang tin-polymetallic district, Guangxi,China, is one of the largest tin ore fields in the world. Both cassiterite-sulfide and Zn–Cu skarn mineralization are hosted in the Mid-Upper Devonian carbonate-rich sediments adjacent to the underlying Cretaceous Longxianggai granite(91–97 Ma). The Lamo Zn–Cu deposit is a typical skarn deposit in the district and occurs at the contact zone between the Upper Devonian limestone and the granite.The ore minerals mainly consist of sphalerite, arsenopyrite,pyrrhotite, galena, chalcopyrite, and minor molybdenite.However, the age of mineralization and source of the metals are not well constrained. In this study, we use the molybdenite Re–Os dating method and in-situ Pb isotopes of sulfides from the Lamo deposit for the first time in order to directly determine the age of mineralization and the tracing source of metals. Six molybdenite samples yielded a more accurate Re–Os isochron age of 90.0 ± 1.1 Ma(MSWD = 0.72), which is much younger than the reported garnet Sm–Nd isochron age of 95 ± 11 Ma and quartz fluid inclusions Rb–Sr isochron age of 99 ± 6 Ma. This age is also interpreted as the age of Zn–Cu skarn mineralization in the Dachang district. Further, in this study we found that in-situ Pb isotopes of sulfides from the Lamo deposit and feldspars in the district's biotite granite and granitic porphyry dikes have a narrow range and an overlap of Pb isotopic compositions(^(206) Pb/^(204) Pb =18.417–18.594,^(207) Pb/^(204) Pb = 15.641–15.746, and^(208) Pb/^(204) Pb = 38.791–39.073), suggesting that the metals were mainly sourced from Cretaceous granitic magma.展开更多
基金Supported by the Science and Technology Planning Project of Jingning County(2024C1)General Project of Meteorological Science and Technology in Lishui City in 2024(202401YB).
文摘Based on the observation data of daily average temperature,daily rainfall and sunshine duration from 2005 to 2024 from the national basic meteorological station and regional meteorological station in Jingning,as well as the data of tea yield and growth period,the first picking date and quality of Huiming tea in Jingning were evaluated by the analysis of physical and chemical indicators and climate quality index of Huiming tea.The results show that in the past two decades,the first picking date of Huiming tea showed a significant advancing trend.Climate warming led to an increase in≥0℃active accumulated temperature,thus advancing the first picking date.The climate quality index of tea was"very excellent"in most years,and the physical and chemical indicators were at the special grade.Tea yield was significantly correlated with multiple meteorological factors,especially closely related to sunshine duration in early February and≥5℃active accumulated temperature from February to April.
文摘BACKGROUND Castleman disease is an uncommon nonclonal lymphoproliferative disorder,which frequently mimics both benign and malignant abnormalities in several regions.Depending on the number of lymph nodes or regions involved,Castleman disease(CD)varies in diagnosis,treatment and prognosis.It rarely occurs in the pancreas alone without any distinct clinical feature and tends to be confused with pancreatic paraganglioma(PGL),neuroendocrine tumors(NETs),and primary tumors,thus impeding proper diagnosis and treatment.CASE SUMMARY A 28-year-old woman presented with a lesion on the neck of the pancreas,detected by ultrasound during a health examination.Physical examination and laboratory findings were normal.The mass showed hypervascularity on enhanced computed tomography(CT),significantly increased 18F-fluorodeoxyglucose uptake on positron emission tomography(PET)/CT,and slightly increased somatostatin receptor(SSTR)expression on^(68)Ga-DOTATATE PET/CT,suggesting no distant metastases and subdiagnoses such as pancreatic PGL,NET,or primary tumor.Intraoperative pathology suggested lymphatic hyperplasia,and only simple tumor resection was performed.The patient was diagnosed with the hyaline vascular variant of CD,which was confirmed by postoperative immunohistochemistry.The patient was discharged successfully,and no recurrence was observed on regular review.CONCLUSION High glucose uptake and slightly elevated SSTR expression are potentially new diagnostic features of CD of the pancreas.
基金co-supported by the Science Center for Gas Turbine Project, China(No. P2022-AB-IV-001-002)the National Natural Science Foundation of China (No. 91960203)+1 种基金the Fundamental Research Funds for the Central Universities (No. D5000230048)the Innovation Capability Support Program of Shaanxi (No. 2022TD-60)
文摘Superior strength and high-temperature performance make γ-TiAl vital for lightweight aero-engines. However, its inherent brittleness poses machining problems. This study employed Elliptical Ultrasonic Vibration Milling (EUVM) to address these problems. Considering the influence of machining parameters on vibration patterns of EUVM, a separation time model was established to analyze the vibration evolutionary process, thereby instructing the cutting mechanism. On this basis, deep discussions regarding chip formation, cutting force, edge breakage, and subsurface layer deformation were conducted for EUVM and Conventional Milling (CM). Chip morphology showed the chip formation was rooted in the periodic brittle fracture. Local dimples proved that the thermal effect of high-speed cutting improved the plasticity of γ-TiAl. EUVM achieved a maximum 18.17% reduction in cutting force compared with CM. The force variation mechanism differed with changes in the cutting speed or the vibration amplitude, and its correlation with thermal softening, strain hardening, and vibratory cutting effects was analyzed. EUVM attained desirable edge breakage by achieving smaller fracture lengths. The fracture mechanisms of different phases were distinct, causing a surge in edge fracture size of γ-TiAl under microstructural differences. In terms of subsurface deformation, EUVM also showed strengthening effects. Noteworthy, the lamellar deformation patterns under the cutting removal state differed from the quasi-static, which was categorized by the orientation angles. Additionally, the electron backscattering diffraction provided details of the influence of microstructural difference on the orientation and the deformation of grains in the subsurface layer. The results demonstrate that EUVM is a promising machining method for γ-TiAl and guide further research and development of EUVM γ-TiAl.
基金supported by the National Natural Science Foundation of China(32172059)Fundamental Research Funds for the Central Universities(SWUXDJH202315).
文摘Pre-harvest sprouting(PHS)describes the germination of physiologically mature grains in spikes prior to harvest in cereal crops.PHS could seriously decrease grain yield and quality,which makes it a major constraint to cereal production worldwide.A number of PHS-associated genes in cereals have been reported;however,the molecular mechanisms underlying PHS remain largely elusive.Here,we report a CRISPRCas9 mutant with severe PHS in a paddy field.The mutated gene OsMFT2 encodes a phosphatidylethanolamine-binding protein(PEBP).Intriguingly,the OsMFT1,in the same PEBP family,had the opposite effect in controlling rice PHS as does OsMFT2.Germination tests of seeds of chimeric protein-expressing plants revealed that the fourth exon conferred the antagonistic activity of OsMFT1 and OsMFT2 in rice PHS.Additionally,two lines of these plants showed elevated grain numbers per panicle,implying that chimeric protein has potential to significantly increase yield.Moreover,transcriptome analysis and genetic studies indicated that OsMFT1 and OsMFT2 performed opposing functions in rice PHS owing to three co-regulated genes that being contrastingly affected by OsMFT1 and OsMFT2.Overall,it seemed that the proper combination of PEBP family members could obtain optimal PHS resistance and high yield.
文摘目的探讨微孔板法、实时荧光PCR熔解曲线技术(简称“熔解曲线法”)、多色巢式实时荧光定量PCR技术(简称“Xpert法”)和罗氏药物敏感性试验(L-J药敏试验,简称“比例法”)用于快速筛查耐多药结核病(MDR-TB)的临床价值。方法从医院信息系统(hospital information system,HIS)连续收集2014年7月至2018年3月重庆市公共卫生医疗救治中心收治的确诊为结核病,且具有微孔板法、比例法、熔解曲线法、Xpert法检测MTB对利福平、异烟肼耐药性诊断结果的2792例患者资料;其中微孔板法、比例法采用阳性分离菌株检测,熔解曲线法和Xpert法采用患者标本直接检测。纳入同时具有微孔板法和比例法耐药性检测结果的1488例患者作为研究对象,其中341例行微孔板法+比例法+Xpert法检测利福平耐药性,87例行微孔板法+比例法+熔解曲线法检测利福平耐药性,66例行微孔板法+比例法+熔解曲线法检测异烟肼耐药性。以比例法为标准,采用SPSS13.0软件分别计算微孔板法、熔解曲线法、Xpert法检测利福平和(或)异烟肼耐药性的敏感度、特异度、符合率、Kappa值等。结果以比例法为标准,微孔板法、Xpert法、熔解曲线法检测利福平耐药性的敏感度、特异度、阳性预测值、阴性预测值、符合率、Kappa值分别为97.2%(731/752)、96.9%(713/736)、96.9%(731/754)、97.1%(713/734)、97.0%(1444/1488)、0.94,97.2%(140/144)、94.9%(187/197)、93.3%(140/150)、97.9%(187/191)、95.9%(327/341)、0.92,97.1%(33/34)、84.9%(45/53)、80.5%(33/41)、97.8%(45/46)、89.7%(78/87)、0.79;微孔板法和熔解曲线法检测异烟肼耐药性的敏感度、特异度、阳性预测值、阴性预测值、符合率、Kappa值分别为94.8%(751/792)、95.7%(667/697)、96.3%(751/780)、94.2%(667/708)、97.9%(1418/1448)、0.91,97.3%(36/37)、86.2%(25/29)、90.0%(36/40)、96.2%(25/26)、92.4%(61/66)、0.84。结论微孔板法、熔解曲线法、Xpert法检测利福平和(或)异烟肼耐药性均具有较高的敏感度和特异度,适合快速筛查耐多药结核病;微孔板法还能获得各药物最低药物浓度,为临床用药剂量的选择提供参考依据。
基金financially supported by the National Natural Science Foundation of China(No.52302229)the State Key Laboratory of Photovoltaic Science and Technology of China(No.202401030301)the Key Lab of Modern Optical Technologies of Education Ministry of China,Soochow University(No.KJS2425)。
文摘Perovskite optoelectronic devices,capitalizing on the exceptional light-matter interaction and semiconductor properties of perovskite materials,have emerged as transformative platforms for energy conversion,information storage,and photonic technologies.While material innovations and device engineering breakthroughs have propelled remarkable advancements,persistent challenges in operational stability,scalable manufacturing,and batch reproducibility continue to hinder commercial implementation.Recently,molecular ferroelectrics(MOFEs),as a class of materials characterized by polar crystal structures and switchable spontaneous polarization(P_(s)),offer novel pathways to regulate high-efficiency and stable perovskite optoelectronic devices.Here,we systematically review the application of MOFEs into diverse perovskite optoelectronic systems,emphasizing the synergistic effect between P_(s)and optoelectronic properties.We analyze MOFEs-based photodetectors spanning self-powered,X-ray,and polarized-light detectors,detailing how P_(s)and synergistic physical effects optimize device performance.For photovoltaic applications,we elucidate polarizationdriven performance enhancement mechanisms in perovskite solar cells(PSCs),including built-in field amplification,defect passivation,and stability improvement.Furthermore,we envisage the emerging applications of MOFEs in optoelectronic fields such as non-volatile memory,neuromorphic computing,and optical communication.Overall,this review furnishes valuable insights into optoelectronics and future energy.
基金funded by the National Natural Science Foundation of China(32372114,31971984)the Special Fund for Youth Team of the Southwest Universities(SWU-XJPY202306)+1 种基金the Chongqing Graduate Scientific Research Innovation Project(CYS23239)the Genetically Modified Organisms Breeding Major Project of China(2018ZX0800921B)。
文摘Sphingolipids are not only a pivotal component of membranes but also act as bioactive molecules.Cotton fiber is one of the longest plant cells and sphingolipids are closely associated with the development of cotton fiber cells.However,their function in cotton fiber cell development and its action mechanism is unclear.Through cotton genetic transformation and chemistry biological approach,we identified the function and action mechanism of the glucosylceramide synthase gene GhGCS1 and its product glucosylceramide(GluCer)in cotton fiber growth.GhGCS1 was preferentially expressed at the stage of fiber elongation and localized in the endoplasmic reticulum.Overexpression of GhGCS1 promoted GluCer synthesis and fiber elongation,which was consistent with the exogenous application of GluCer(FA-C22)(containing very long-acyl-chain fatty acid)to cotton fiber in ovule culture system in vitro.Contrarily,suppressing GhGCS1 expression inhibited GluCer synthesis and fiber elongation,which was similar as the exogenous application of GluCer synthesis inhibitor,PDMP.Transcriptome analysis revealed that the fiber elongation regulated by GhGCS1 was associated with brassinosteroid(BR)synthesis and signaling related gene expression.Meanwhile,we detected the BL content of control and transgenic fiber cells.The BL content significantly increased and decreased in up-and down-regulated transgenic fibers when compared with control fibers,respectively.Furthermore,we found that PDMP treatment blocked BR synthesis and signal transduction,while exogenous application of GluCer could enhance BR synthesis and signaling.Overall,our results revealed that GhGCS1 and GluCer regulated cotton fiber elongation by influencing BR synthesis and signaling.Our study shed a novel insight on regulatory mechanism of cotton fiber elongation and provides theoretical support,genetic resources and novel transgenic materials for improvement of crop quality.
文摘Under the current background of an information society,the digital transformation of enterprises has become a necessary means to enhance the competitiveness of enterprises.This article is based on the industrial Internet platform,the digital planning and architecture of enterprises research.First,we analyze the current challenges of digital transformation and the development opportunities brought by the industrial Internet.Then,we propose a digital planning method based on the industrial Internet platform,which takes the full connectivity of people,machine and things and intelligent decision making as the core,takes data collection,processing,analysis and application as the main line,and finally forms the top-level design of the digital transformation of enterprises.At the same time,we also built an industrial Internet platform architecture model,including the previous end perception layer,network transmission layer,platform service layer,and application innovation layer for four levels,to support enterprises in innovative applications and decision support under the industrial Internet environment.Research shows that this kind of enterprise digital planning and architecture based on an industrial Internet platform can effectively promote enterprises to achieve business model innovation,system innovation,and strengthen the flexibility and agility of enterprises to respond to market changes.The results of this research not only have important theoretical and practical significance for guiding enterprises to carry out digital planning and build an industrial Internet platform,but also provide useful reference for relevant policy formulation.
文摘This study presents a comprehensive mechanical analysis of P110S oil tubing subjected to thermal and chemical coupling effects,with particular attention to the presence of rectangular corrosion defects.Drawing on the material’s stress–strain constitutive behavior,thermal expansion coefficient,thermal conductivity,and electrochemical test data,the research incorporates geometric nonlinearities arising from large deformations induced by corrosion.A detailed three-dimensional finite element(FE)model of the corroded P110S tubing is developed to simulate its response under complex loading conditions.The proposed model is rigorously validated through full-scale burst experiments and analytical calculations based on theoretical formulations.Building upon this validation,the Extended Finite Element Method(XFEM)and a failure criterion grounded in damage evolution mechanics are applied to investigate the mechanical behavior of the tubing under the coupled influences of temperature,stress,and chemical corrosion.Special emphasis is placed on the role of rectangular corrosion features in determining failure mechanisms.To further elucidate the impact of multiple interacting parameters,a sensitivity analysis is performed by integrating grey correlation theory with simulation outcomes.Based on these findings,the study systematically explores the elastic–plastic deformation process,crack initiation and propagation behavior,and the burst failure response of tubing specimens with varying axial lengths and depths of corrosion.The proposed methodology provides a robust predictive framework for petroleum engineers to evaluate fracture pressure,diagnose failure modes,assess operational risks,and optimize production strategies.
基金supported by the National Natural Science Foundation of China(Nos.92156021,22350009,and 22101115)Financial Support for Outstanding Talents Training Fund in Shenzhen,the Guangdong Provincial Key Laboratory of Catalysis(No.2020B121201002)+2 种基金high level of special funds(No.G03050K003)Introduction of Major Talent Projects in Guangdong Province(No.2019CX01C079)supported by the Center for Computational Science and Engineering at SUSTech.
文摘Azulene-fused acenes demonstrate enhanced stability,unique aromaticity,and distinctive photophysical properties,rendering them significant in organic electronics.In the present study,we report a new type of nonalternant analogue of pentacene incorporating a non-terminal azulene unit.Aromaticity analyses reveal that the five-membered rings in this analogue exhibit antiaromatic.The extensive conjugated aryl substituents on the acene’s side shift the HOMO distributions from the naphthyl ring and metallacycle to the aryl groups,thereby narrowing the HOMO-LUMO energy gap and enhancing absorptions in the low-energy regions.Furthermore,these fused acenes readily react with base rather than acid,resulting in reversible base/acid stimuli responsiveness.
基金supported by the Sichuan Provincial Regional Innovation Cooperation Project(No.2024YFHZ0159).
文摘Semicrystalline polymers usually undergo multilevel microstructural evolutions with annealing and stretching processes,which is es-sential to tailor the physical properties of the polymer.Here,poly(butylene carbonate)(PBC)sheets were prepared via isothermal annealing and unidirectional pre-stretching processes,then the changes of PBC in crystallinity,mechanical properties,thermal properties and microscopic changes before and after annealing and stretching were measured,as well as the relationship between microstructure and macroscopic proper-ties before and after stretching.The strengthening mechanism of PBC was also described.It was demonstrated that shish-kabab structure emerged under the pre-stretching process.With the increase of the tensile ratio,the crystallinity,structure and mechanical properties are in-creased differently.Among them,the crystallinity and tensile strength after annealing-stretching treatment increased to 24.45%and 104.5 MPa,respectively,which were about 1.55 times and 3.4 times of those-without any treatment.
基金supported by the National Key Research and Development Program of China(No.2022YFB3804504)the National Natural Science Foundation of China,Youth Project(Nos.82101838,82203367,82203505,and 82203403)the Experimental Animal Fund of Shanghai Science and Technology Commission(No.22140903800).
文摘Epidemiological studies indicate that prostate cancer(PCa)is the second prevalent malignant tumor affecting men globally.Environmental pollution such as cigarette smoke is one of the important risk factors for the development of prostate cancer.However,as one of the main carcinogens in cigarette smoke,the role of benzo[a]pyrene(BaP)in prostate cancer is still unclear.The current study aimed to investgate the impacts of BaP exposure on the progression of PCa towardmalignancy and the regulation of the immune microenvironment.We verified that BaP exposure can promote the proliferation,migration,and apoptosis of prostate cancer cells through in vitro experiments.We constructed a subcutaneous xenograft tumor model of BaP exposure mouse and found that can promote the proliferation of tumors in vivo.Organoids-driven by PCa patients showed higher growth rate under BaP exposure.Flow cytometric analysis demonstrated a remarkable decrease in CD4^(+)T and CD8^(+)T cell infiltration levels.Moreover,we identified four genes(Mdm2,Ar,Foxo1,Crebbp)were strongly associated with BaP exposure by combining mouse tumor RNA-seq and CTD database.Additionally,a nomogram integrating clinicopathological features was constructed to assess the prognosis of prostate cancer patients under BaP exposure.This study systematically proved that BaP exposure promotes malignant progression of PCa and suppresses the immune microenvironment,in which Mdm2,Ar,Foxo1,Crebbp may play a crucial role in inhibiting apoptosis.These findings offer novel insights into themechanisms via which BaP exposure contributes to PCa development.
文摘目的探索中国宁夏人群中HOTAIR单核苷酸多态性与胃癌(gastric cancer, GC)易感性的相关性研究.方法挑选3个H O TA I R基因位点r s12826786(C>T),rs920778(C>T), RS4759314(A>G),对其多态性进行了基因分型;选取152名GC患者和307名健康对照者,按照年龄,体重,性别等因素相匹配,通过PCR与高通量TaqMan分析其单核苷酸多态性对于GC遗传易感性的影响.结果HOTAIRRs920778位点基因型TT在病例组和对照组中的频率分别为26.3%和24.7%,基因型C/T在两组中的频率分别为21.1%和31.3%,基因型CC在两组中的频率分别为52.6%和44.0%,该位点的TT基因型与GC的遗传易感性具有显著联系,结果具有统计学意义(P <0.05).Rs12826786和Rs4759314两个基因位点与GC发病危险关系的结果并无统计学意义(P>0.05).进一步的分层分析中发现Rs920778位点的单核苷酸多态性与男性,吸烟人群及肿瘤大小≥5 cm的GC患者的GC遗传易感性高度相关,而与患者的年龄因素,女性患者,非吸烟患者,患者的远处转移情况及GC家族史并无显著联系.结论中国宁夏人群中HOTAIR Rs920778位点单核苷酸多态性与GC的遗传易感性具有一定程度的联系.
基金This study was funded by the Science and Technology Commission of Wuhan City (No.WX16B02)and Natural Science Foundation of Hubei Province (No.2018CFB353).
文摘The efficacy and applied value of endoscopic hematoma evacuation vs. external ventricular drainage (EVD) in the treatment of severe ventficular hemorrhage (IVH) were explored and compared.From Jan.2015 to Dec.2016,the clinical data of 42 cases of IVH were retrospectively analyzed,including 18 patients undergoing endoscopic hematoma evacuation (group A),and 24patients receiving EVD (group B).The hematoma clearance rate was calculated by 3D Slicer software,and complications and outcomes were compared between the two groups.There were no significant differences in age,sex and Graeb score between groups A and B (P>0.05).The hematoma clearance rate was 70.81%±27.64% in group A and 48.72%±36.58% in group B with a statistically significant difference (P<0.05).The operative time in groups A and B was 72.45±25.26 min and 28.54±15.27min,respectively (P<0.05).The Glasgow Coma Scale (GCS) score increased from 9.28±2.72 at baseline to 11.83±2.91 at 1 week postoperatively in group A,and from 8.25±2.62 at baseline to 10.79±4.12 at 1 week postoperatively in group B (P<0.05).The length of hospital stay was 12.67±5.97 days in group A and 17.33±8.91 days in group B with a statistically significant difference (P<0.05).The GOS scores at 6 months after surgery were 3.83±1.12 in group A,and 2.75±1.23 in group B (P<0.05). These results suggested that endoscopic hematoma evacuation has an advantage of a higher hematoma clearance rate,fewer complications and better outcomes in the treatment of severe IVH,indicating it is a safe,effective and promising approach for severe IVH.
基金supported by the China National Science and Technology Major Project(No.2015ZX04001202)
文摘The Blade Integrated Disk(Blisk) is one of the key components in the aero-engine, it is generally manufactured by the multi-axis milling and almost 90% raw materials are removed. To avoid the full immersion of a cutter in the rough machining of a blisk channel, the trochoidal milling is a promising strategy since it can keep a small immersion angle in the rough milling process while maintaining the high machining efficiency. However, while toolpaths are being planned for the trochoidal milling process, the conventional methods are mainly for the planar machining area with fixed tool orientations, which cannot be used for complex channels where the multi-axis machining should be employed. To this end, this paper presents a four-axis trochoidal toolpath planning method with a ball-end cutter, and thus the blisk channel can be machined efficiently.For this to happen, the trochoidal paths are planned in the parametric domain and then mapped into the physical domain, with tool orientations controlled by the quaternion interpolation method to have smooth tool movement along the toolpaths. Both geometric simulation and physical milling experiments of the proposed method have convincingly demonstrated the validation of the proposed method.
文摘Hepatic encephalopathy(HE) is a severe neuropsychiatric syndrome that most commonly occurs in decompensated liver cirrhosis and incorporates a spectrumof manifestations that ranges from mild cognitive impairment to coma. Although the etiology of HE is not completely understood, it is believed that multiple underlying mechanisms are involved in the pathogenesis of HE, and one of the main factors is thought to be ammonia; however, the ammonia hypothesis in the pathogenesis of HE is incomplete. Recently, it has been increasingly demonstrated that inflammation, including systemic inflammation, neuroinflammation and endotoxemia, acts in concert with ammonia in the pathogenesis of HE in cirrhotic patients. Meanwhile, a good number of studies have found that current therapies for HE, such as lactulose, rifaximin, probiotics and the molecular adsorbent recirculating system, could inhibit different types of inflammation, thereby improving the neuropsychiatric manifestations and preventing the progression of HE in cirrhotic patients. The antiinflammatory effects of these current therapies provide a novel therapeutic approach for cirrhotic patients with HE. The purpose of this review is to describe the inflammatory mechanisms behind the etiology of HE in cirrhosis and discuss the current therapies that target the inflammatory pathogenesis of HE.
基金co-supported by the Science Center for Gas Turbine Project,China(No.P2022-A-IV-001-002)the National Natural Science Foundation of China(Nos.51875473 and 91960203).
文摘Owing to its outstanding mechanical properties,γ-TiAl is desirable materials for crossgeneration aero-engines.Nearly 70 years of exploration have made it into the initial application.However,the intrinsic brittleness ofγ-TiAl is still a critical obstacle to its large-scale applications.In this context,researchers have made many attempts to study the machinability ofγ-TiAl.At present,existing relevant reviews have mostly discussed the processing methods ofγ-TiAl.Hence,there is still a lack of a perspective on material properties to analyze the cutting mechanism.Herein,this paper provides the systematic review of such perspectives.Above all,the developmental process,phase transformation,and microstructural evolution ofγ-TiAl are discussed,as well as its deformation mechanism at quasi-static.These topics can provide a materials science foundation for the machining ofγ-TiAl.And then,the review focuses on the cutting mechanism and surface integrity ofγ-TiAl.Moreover,special attention is paid to the microscope deformation mechanism and surface defects evolution ofγ-TiAl during cutting.Finally,the review indicates that the highperformance machining technology ofγ-TiAl faces challenges and proposes potential future research directions.Solving the difficulties during machiningγ-TiAl aero-engine components will accelerate the development of new aero-engines.
基金supported by the National Natural Science Foundation of China(Nos.52005413,52022082)Natural Science Basic Research Plan in Shaanxi Province of China(No.2021JM-054)the Fundamental Research Funds for the Central Universities(No.D5000220135)。
文摘Geometric error,mainly due to imperfect geometry and dimensions of machine components,is one of the major error sources of machine tools.Considering that geometric error has significant effects on the machining quality of manufactured parts,it has been a popular topic for academic and industrial research for many years.A great deal of research work has been carried out since the 1970s for solving the problem and improving the machining accuracy.Researchers have studied how to measure,detect,model,identify,reduce,and compensate the geometric errors.This paper presents a thorough review of the latest research activities and gives an overview of the state of the art in understanding changes in machine tool performance due to geometric errors.Recent advances in measuring the geometrical errors of machine tools are summarized,and different kinds of error identification methods of translational axes and rotation axes are illustrated respectively.Besides,volumetric geometric error modeling,tracing,and compensation techniques for five-axis machine tools are emphatically introduced.Finally,research challenges in order to improve the volumetric accuracy of machine tools are also highlighted.
基金supported by the National Science Foundation of China(Grants Nos.41672080,41772079,41272113)Outstanding Talent Foundation of the Institute of Geochemistry,Chinese Academy of Sciences
文摘The Dachang tin-polymetallic district, Guangxi,China, is one of the largest tin ore fields in the world. Both cassiterite-sulfide and Zn–Cu skarn mineralization are hosted in the Mid-Upper Devonian carbonate-rich sediments adjacent to the underlying Cretaceous Longxianggai granite(91–97 Ma). The Lamo Zn–Cu deposit is a typical skarn deposit in the district and occurs at the contact zone between the Upper Devonian limestone and the granite.The ore minerals mainly consist of sphalerite, arsenopyrite,pyrrhotite, galena, chalcopyrite, and minor molybdenite.However, the age of mineralization and source of the metals are not well constrained. In this study, we use the molybdenite Re–Os dating method and in-situ Pb isotopes of sulfides from the Lamo deposit for the first time in order to directly determine the age of mineralization and the tracing source of metals. Six molybdenite samples yielded a more accurate Re–Os isochron age of 90.0 ± 1.1 Ma(MSWD = 0.72), which is much younger than the reported garnet Sm–Nd isochron age of 95 ± 11 Ma and quartz fluid inclusions Rb–Sr isochron age of 99 ± 6 Ma. This age is also interpreted as the age of Zn–Cu skarn mineralization in the Dachang district. Further, in this study we found that in-situ Pb isotopes of sulfides from the Lamo deposit and feldspars in the district's biotite granite and granitic porphyry dikes have a narrow range and an overlap of Pb isotopic compositions(^(206) Pb/^(204) Pb =18.417–18.594,^(207) Pb/^(204) Pb = 15.641–15.746, and^(208) Pb/^(204) Pb = 38.791–39.073), suggesting that the metals were mainly sourced from Cretaceous granitic magma.
