In order to investigate the true post distribution in the whole society, microelasticity （MIE） and macroelasticity （MAE） were defined by regarding all posts as a system. On this basis, the method for measuring pos...In order to investigate the true post distribution in the whole society, microelasticity （MIE） and macroelasticity （MAE） were defined by regarding all posts as a system. On this basis, the method for measuring post distribution was proposed. Using the Legendre dual transformation between MIE and MAE to highlight the probabilities of different levels, the post distribution were analyzed hierarchically. The two-scale Cantor model verified that the multifractal measure is applicable to the post distribution evolution process.展开更多
BACKGROUND Delayed post hypoxic leukoencephalopathy syndrome(DPHLS),also known as Grinker’s myelinopathy,is a rare but significant neurological condition that manifests days to weeks after a hypoxic event.Characteriz...BACKGROUND Delayed post hypoxic leukoencephalopathy syndrome(DPHLS),also known as Grinker’s myelinopathy,is a rare but significant neurological condition that manifests days to weeks after a hypoxic event.Characterized by delayed onset of neurological and cognitive deficits,DPHLS presents substantial diagnostic and therapeutic challenges.AIM To consolidate current knowledge on pathophysiology,clinical features,diagnostic approaches,and management strategies for DPHLS,providing a comprehensive overview and highlighting gaps for future research.METHODS Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes guidelines,we systematically searched PubMed,ScienceDirect and Hinari databases using terms related to delayed post-hypoxic leukoencephalopathy.Inclusion criteria were original research articles,case reports,and case series involving human subjects with detailed clinical,neuroimaging,or pathological data on DPHLS.Data were extracted on study characteristics,participant demographics,clinical features,neuroimaging findings,pathological findings,treatment,and outcomes.The quality assessment was performed using the Joanna Briggs Institute critical appraisal checklist.RESULTS A total of 73 cases were reviewed.Common comorbidities included schizoaffective disorder,bipolar disorder,hypertension,and substance use disorder.The primary causes of hypoxia were benzodiazepine overdose,opioid overdose,polysubstance overdose,and carbon monoxide(CO)poisoning.Symptoms frequently include decreased level of consciousness,psychomotor agitation,cognitive decline,parkinsonism,and encephalopathy.Neuroimaging commonly revealed diffuse T2 hyperintensities in cerebral white matter,sometimes involving the basal ganglia and the globus pallidus.Magnetic resonance spectroscopy often showed decreased N-acetylaspartate,elevated choline,choline-to-creatinine ratio,and normal or elevated lactate.Treatment is often supportive,including amantadine,an antioxidant cocktail,and steroids.Hyperbaric oxygen therapy may be beneficial in those with CO poisoning.Parkinsonism was often treated with levodopa.Most of the patients had substantial recovery over the course of months and many cases had some residual neurocognitive deficits.CONCLUSION DPHLS remains a complex and multifaceted condition with various etiologies and clinical manifestations.Early recognition and appropriate management are crucial to improving patient outcomes.Future research should focus on standardizing diagnostic criteria,using advanced imaging techniques,and exploring therapeutic interventions to improve understanding and treatment of DPHLS.Conducting prospective cohort studies and developing biomarkers for early diagnosis and monitoring will be essential to advance patient care.展开更多
Cardiac arrest(CA)is a critical condition in the field of cardiovascular medicine.Despite successful resuscitation,patients continue to have a high mortality rate,largely due to post CA syndrome(PCAS).However,the inju...Cardiac arrest(CA)is a critical condition in the field of cardiovascular medicine.Despite successful resuscitation,patients continue to have a high mortality rate,largely due to post CA syndrome(PCAS).However,the injury and pathophysiological mechanisms underlying PCAS remain unclear.Experimental animal models are valuable tools for exploring the etiology,pathogenesis,and potential interventions for CA and PCAS.Current CA animal models include electrical induction of ventricular fibrillation(VF),myocardial infarction,high potassium,asphyxia,and hemorrhagic shock.Although these models do not fully replicate the complexity of clinical CA,the mechanistic insights they provide remain highly relevant,including post-CA brain injury(PCABI),post-CA myocardial dysfunction(PAMD),systemic ischaemia/reperfusion injury(IRI),and the persistent precipitating pathology.Summarizing the methods of establishing CA models,the challenges encountered in the modeling process,and the mechanisms of PCAS can provide a foundation for developing standardized CA modeling protocols.展开更多
1 Introduction The recent emergence of human-like language models like ChatGPT has raised concerns regarding the potential abuse of LLMs for malicious purposes[1,2].Detecting text generated by LLMs has become critical...1 Introduction The recent emergence of human-like language models like ChatGPT has raised concerns regarding the potential abuse of LLMs for malicious purposes[1,2].Detecting text generated by LLMs has become critically important[3].展开更多
The effects of post heat treatment on the microstructure,aging kinetics,and room/elevated temperature mechanical properties of additively manufactured Inconel 718 superalloy were investigated.Scanning electron microsc...The effects of post heat treatment on the microstructure,aging kinetics,and room/elevated temperature mechanical properties of additively manufactured Inconel 718 superalloy were investigated.Scanning electron microscopy(SEM),electron backscattered diffraction(EBSD),and X-ray diffraction(XRD),as well as hardness,tensile,and creep testing were used for characterization.At temperatures higher than 1100°C,homogenization treatment resulted in the appearance of equiaxed grains by recrystallization and diminishing the dislocation density.The precipitation activation energy for the homogenized and aged condition was obtained as 203.2 kJ/mol,which was higher than the value of~160 kJ/mol for the as-built IN718 superalloy.Therefore,direct aging resulted in a faster aging response,which led to a significant improvement in tensile properties,as rationalized by the strengthening mechanisms.Direct aging treatment resulted in a higher elevated-temperature ultimate tensile strength(UTS)as well as the optimum creep life and the lowest minimum creep rate in comparison with other heat treatment routes,which were attributed to the presence of fine and uniformly dispersed strengthening precipitates in conjunction with the high dislocation density.展开更多
Cardiac arrest is associated with high rates of mortality and significant long-term neurological disability in survivors.Timely and accurate assessment following successful resuscitation is critical for optimizing out...Cardiac arrest is associated with high rates of mortality and significant long-term neurological disability in survivors.Timely and accurate assessment following successful resuscitation is critical for optimizing outcomes.Imaging plays a central role in this evaluation process,providing crucial insights into the etiology of arrest,the extent of cerebral and cardiac injury,and guiding both acute management and long-term prognostication.A structured,multimodal imaging approach utilizing tools such as computed tomography,magnetic resonance imaging,echocardiography,and angiography is increasingly recognized as es-sential in the post-cardiac arrest setting.This review aims to consolidate current evidence related to the use of various imaging modalities across neurological,cardiac and systemic contexts.Particular emphasis is placed on the prognostic value and optimal timing of neuroimaging,the detection of potentially reversible causes of arrest,such as coronary occlusion or pulmonary embolism,and the emerging role of whole-body imaging in evaluating patients with non-traumatic out-of-hospital cardiac arrest.展开更多
High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of equipment.This study proposed a variable cross-section damped ...High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of equipment.This study proposed a variable cross-section damped steel support frame(VCDFS)with viscous dampers to reduce seismic responses of both tall and low-rise electrical equipment.The VCDFS contains a trapezoidal damper layer to generate rocking motions,enabling the diagonal viscous dampers to dissipate seismic inputs.A theoretical model of post equipment with VCDFS is established,and an optimal design procedure is proposed.The analysis shows that the remaining static stiffness ratio λ_(k) is the key parameter that determines the effectiveness of the VCDFS.The VCDFS reduces the average displacement and stress response of a post insulator by 39.4%and 44.6%,respectively,together with a significant decrease in the dynamic amplification factor.Therefore,it is recommended to use the VCDFS instead of the conventional latticed-steel frame in earthquake zones.展开更多
Mental health disorders have emerged as a critical global health challenge,profoundly impacting individuals,communities,and societies worldwide.The prevalence of mental health problems has been steadily increasing,wit...Mental health disorders have emerged as a critical global health challenge,profoundly impacting individuals,communities,and societies worldwide.The prevalence of mental health problems has been steadily increasing,with~1 in 8 people,equivalent to 970 million individuals suffering from a mental disorder in 2019(https://vizhub.healthdata.org/gbd-results).Anxiety and depressive disorders are predominant,contributing significantly to the burden of mental health issues,according to the World Health Organization.The COVID-19 pandemic has further exacerbated this situation.It led to a notable upsurge in anxiety and major depressive disorders in 2020.Estimates indicate a 26%rise in anxiety and a 28%increase in depression within that year(https://www.who.int/publications/i/item/WHO-2019-nCoVSci_Brief-Mental_health-2022.1)[1].展开更多
This study analyzed through-thickness distribution of residual stress in a 106 mm ultra-thick TC4 titanium alloy electron beam welded(EBW)joint after post weld heat treatment(PWHT)using X-ray diffraction(XRD)and deep-...This study analyzed through-thickness distribution of residual stress in a 106 mm ultra-thick TC4 titanium alloy electron beam welded(EBW)joint after post weld heat treatment(PWHT)using X-ray diffraction(XRD)and deep-hole drilling(DHD)methods,and investigated the microstructure and mechanical properties.During the PWHT at 600℃,a phase transformation(β→α)occurred in the EBW joint and affected the residual stress distribution and mechanical properties.The surface residual stress was mainly compressive stress,while the internal residual stress was mainly tensile stress in the welded joint.For the as-welded joint,the absolute value of surface residual stress was higher than the absolute value of internal residual stress.After PWHT,the residual stress in the treated joint was substantially reduced compared to the as-welded joint,particularly the surface stress,which relieved from−425 to−90 MPa.However,the residual stress relief effect had minimal positive impact on the internal region at 600℃.PWHT resulted in a shift of the joint fracture location from the fusion zone(FZ)to the base metal(BM),and therefore exerted no noticeable effect on the joint strength,but increased the joint elongation significantly.This study provides valuable insights into the regulation of residual stress distribution of ultra-thick titanium alloy plates.展开更多
Diffusion-bonded Ti_(2)AlNb-based alloys commonly present a low strength compared with the deformed or aged ones. In this study, the post heat treatment including solution and aging treatments is proposed to optimize ...Diffusion-bonded Ti_(2)AlNb-based alloys commonly present a low strength compared with the deformed or aged ones. In this study, the post heat treatment including solution and aging treatments is proposed to optimize the microstructure, contributing to strength improvement and appropriate ductility sacrifice. An available method by the introduction of fine size (both 20-100 nm) and a high fraction (59.7% and 13.7%) of O and α_(2) phases using both solution at 1000℃ for 1 h and aging at 750℃ for 5 h can result in excellent tensile strength (992 MPa and 858 MPa) at room temperature and 650℃, respectively, which increases 5.3% and 44.5% than that of as-received sample. The aging treatment can contribute to lamellar O and α2 grains precipitated from the B_(2) parent, which results in limited dislocation slip systems and slip spaces to resist plastic deformation. Moreover, the crack propagation and fracture surfaces are also comparatively analyzed to reveal the fracture behaviors in the samples with high and low strength. This study can provide a new method for the mechanical property optimization of the welded Ti_(2)AlNb alloys.展开更多
The diagnosis and treatment processes for long COVID have been relatively slow to develop for several reasons,such as a lack of consensus about its definition among medical professionals and researchers,and restricted...The diagnosis and treatment processes for long COVID have been relatively slow to develop for several reasons,such as a lack of consensus about its definition among medical professionals and researchers,and restricted access to knowledge from the relevant pandemics of the past.Legacies of viral pandemics unfortunately do not include sufficient research on how the acute symptoms of infection evolved into chronic health conditions.More so,the idea of surviving a viral pandemic with long-lasting symptoms is not new,yet it is curiously disjointed as a medical concept throughout documented histories on the subject.Individuals with long-term conditions that are rooted in acute viral infections,such as COVID-19,require a coordinated system of care that includes comprehensive rehabilitation.This commentary will discuss the philosophical underpinnings of the historical scarcity of documented incidences of individuals with chronic virus symptoms and the need for a shift in post-viral infection treatment approaches.展开更多
BACKGROUND Historically intraoperative drains were employed after pancreatic surgery but over the last decade,there has been debate over the routine usage of drains.AIM To assess the necessity of intra-abdominal drain...BACKGROUND Historically intraoperative drains were employed after pancreatic surgery but over the last decade,there has been debate over the routine usage of drains.AIM To assess the necessity of intra-abdominal drain placement,identify the most effective drain type,and determine the optimal timing for drain removal.METHODS A systematic review of electronic databases,including PubMed,MEDLINE,PubMed Central,and Google Scholar,was conducted using Medical Subject Headings and keywords until December 2023.From an initial pool of 1910 articles,48 were included after exclusion and screening.The primary outcomes analyzed were clinically relevant postoperative pancreatic fistula(CR-POPF),delayed gastric emptying(DGE),overall morbidity,and mortality.Subgroup analyses were performed for pancreaticoduodenectomy and distal pancreatectomy.RESULTS Routine use of drains is associated with a statistically significant increase in the risk of CR-POPF and DGE.Conversely,patients who did not have drains placed experienced a significant reduction in morbidity,readmission rates,and reoperations.No significant differences were observed between active and passive drain types.Early drain removal(<3 days)yielded favorable outcomes compared to delayed removal.CONCLUSION Analysis of randomized controlled trials and cohort studies did not demonstrate an advantage of routine drain placement following pancreatic resection,potentially contributing to increased morbidity and mortality.The decision to use drains should be left to the discretion of the operating surgeon.However,early drain removal can substantially reduce morbidity.展开更多
Chak-hao,the Forbidden Rice from Manipur,India,is an aromatic,purplish-black rice variety that has been awarded a geographical indication tag to preserve and promote its traditional cultivation in Manipur,India.Althou...Chak-hao,the Forbidden Rice from Manipur,India,is an aromatic,purplish-black rice variety that has been awarded a geographical indication tag to preserve and promote its traditional cultivation in Manipur,India.Although Chak-hao is a hardy landrace with field tolerance to biotic stress,its grains are highly susceptible to storage pest infestations,particularly those caused by the rice weevil(Sitophilus oryzae).This severely compromises its commercial storage quality,as pest damage reduces both nutritional value and quantity.展开更多
This article discusses the evolving real-world practice using nitazoxanide,nonsteroidal anti-inflammatory drugs(NSAIDs)and/or azithromycin(Kelleni’s protocol)to manage the evolving manifestations of severe acute resp...This article discusses the evolving real-world practice using nitazoxanide,nonsteroidal anti-inflammatory drugs(NSAIDs)and/or azithromycin(Kelleni’s protocol)to manage the evolving manifestations of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron EG.5.1,its descendant HV.1 as well as BA.2.86 and its descendant JN.1 subvariants in Egypt in 2024.These subvariants are well-known for their highly evolved immune-evasive properties and the manifestations include some peculiar manifestations as persistent cough besides high fever in young children as well as high fever,persistent severe cough,change of voice,loss of taste and smell,epigastric pain,nausea,vomiting,diarrhea,generalized malaise and marked bone aches in adults including the high-risk groups.It’s suggested that the ongoing SARS-CoV-2 evolution is continuing to mostly affect the high-risk groups of patients,to some of whom we’ve also successfully prescribed nitazoxanide and/or NSAIDs for post-exposure prophylaxis of all household contacts.We also continue to recommend starting the immune-modulatory antiviral Kelleni’s protocol as soon as possible in the course of infection and adjusting it in a personalized manner to be more aggressive from the beginning for the high risk patients,at least until the currently encountered surge of infections subsides.展开更多
Background Quantitative flow ratio(QFR) holds significant value in guiding drug-coated balloon(DCB) treatment and enhancing outcomes. However, the predictive capability of post-angioplasty QFR for long-term clinical e...Background Quantitative flow ratio(QFR) holds significant value in guiding drug-coated balloon(DCB) treatment and enhancing outcomes. However, the predictive capability of post-angioplasty QFR for long-term clinical events in patients with de novo lesions who receive DCB treatment remains uncertain. The aim of this study was to explore the potential significance of post-angioplasty QFR measurements in predicting clinical outcomes in patients underwent DCB treatment for de novo lesions.Methods Patients who underwent DCB-only intervention for de novo lesions were enrolled. QFR was conducted after DCB treatment. The patients were then categorized based on post-angioplasty QFR. The primary endpoint was major adverse cardiac events(MACE), encompassing all-cause death, cardiovascular death, nonfatal myocardial infarction, stroke, and target vessel revascularization.Results A total of 553 patients with 561 lesions were included. The median follow-up period was 505 days, during which 66(11.8%) MACEs occurred. Based on post-procedural QFR grouping, there were 259 cases in the high QFR group(QFR > 0.93) and302 cases in the low QFR group(QFR ≤ 0.93). Kaplan-Meier analysis revealed a significantly higher cumulative incidence of MACE in the low QFR group(log-rank P = 0.004). The multivariate Cox proportional hazards model demonstrated a significant inverse correlation between QFR and the occurrence of MACEs(HR = 0.522, 95%CI: 0.289-0.942, P = 0.031). Landmark analysis indicated that high QFR had a significant reducing effect on the cumulative incidence of MACEs within 1 year(log-rank P = 0.016)and 1-5 years(log-rank P = 0.026).Conclusions In patients who underwent DCB-only treatment for de novo lesions, higher post-procedural QFR values(> 0.93)were identified as an independent protective factor against adverse prognosis.展开更多
A conventional non-computerized numerical control （CNC） machine is updated by mounting a six degree-of-free （DOF） parallel mechanism on it, thus obtaining a new CNC one. The structure of this CNC milling machine i...A conventional non-computerized numerical control （CNC） machine is updated by mounting a six degree-of-free （DOF） parallel mechanism on it, thus obtaining a new CNC one. The structure of this CNC milling machine is introduced, and the workpiece locating system and the post processing system of the cutter location （CL） data file are analyzed. The new machine has advantages of low costs, simple structure, good rigidity, and high precision. It is easy to be transformed and used to process the workpiece with a complex surface.展开更多
This paper discusses some aspects of finite element computation,such as the automatic generation of finite element ,refinement of mesh,process of node density, distribution of load,optimum design and the drawing o...This paper discusses some aspects of finite element computation,such as the automatic generation of finite element ,refinement of mesh,process of node density, distribution of load,optimum design and the drawing of stress contour, and describes the developing process of software for a planar 8 node element.展开更多
The observational line of sight velocity fields of a large post flare loop(PFL) system on August 17,1989 were derived based on “multi cloud model” (MCM) method from the Hβ spectral data obtained with the two dimens...The observational line of sight velocity fields of a large post flare loop(PFL) system on August 17,1989 were derived based on “multi cloud model” (MCM) method from the Hβ spectral data obtained with the two dimensional Multi Waveband Spectra Spectro Helio Graph (MW SSHG) at Yunnan Observatory. In order to explain the fundamental features of the velocity fields observed,an assumption and approximation to be taken into account that the matter within a loop system rises up from the loop foot to the loop top along the loop leg in a helical magnetic line under the combined action of solar gravity, magnetic stress and a gradient of atmospheric pressure in the loop system, and a theoretical velocity field of the loop system was calcuated with the aid of MHD theory. From a comparison of both velocity fields, it is found that the computed velocity field is basically similar with the observed one. It indicates that the assumption and approximation mentioned above are suitable basically.展开更多
We focus on the importance and necessity of post-competency-based training in medical education alongside its current challenges and opportunities.Integrating post competency training into standardized educational fra...We focus on the importance and necessity of post-competency-based training in medical education alongside its current challenges and opportunities.Integrating post competency training into standardized educational frameworks is increasingly recognized as a critical component of preparing residents and postgraduates for real-world clinical practice.Post competency training represents a commitment to excellence in medical education,striving to produce competent,skilled practitioners to meet the challenges of modern healthcare.展开更多
基金The National Natural Science Foundation of China (Nos.70771095 and 70572089)
文摘In order to investigate the true post distribution in the whole society, microelasticity （MIE） and macroelasticity （MAE） were defined by regarding all posts as a system. On this basis, the method for measuring post distribution was proposed. Using the Legendre dual transformation between MIE and MAE to highlight the probabilities of different levels, the post distribution were analyzed hierarchically. The two-scale Cantor model verified that the multifractal measure is applicable to the post distribution evolution process.
文摘BACKGROUND Delayed post hypoxic leukoencephalopathy syndrome(DPHLS),also known as Grinker’s myelinopathy,is a rare but significant neurological condition that manifests days to weeks after a hypoxic event.Characterized by delayed onset of neurological and cognitive deficits,DPHLS presents substantial diagnostic and therapeutic challenges.AIM To consolidate current knowledge on pathophysiology,clinical features,diagnostic approaches,and management strategies for DPHLS,providing a comprehensive overview and highlighting gaps for future research.METHODS Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes guidelines,we systematically searched PubMed,ScienceDirect and Hinari databases using terms related to delayed post-hypoxic leukoencephalopathy.Inclusion criteria were original research articles,case reports,and case series involving human subjects with detailed clinical,neuroimaging,or pathological data on DPHLS.Data were extracted on study characteristics,participant demographics,clinical features,neuroimaging findings,pathological findings,treatment,and outcomes.The quality assessment was performed using the Joanna Briggs Institute critical appraisal checklist.RESULTS A total of 73 cases were reviewed.Common comorbidities included schizoaffective disorder,bipolar disorder,hypertension,and substance use disorder.The primary causes of hypoxia were benzodiazepine overdose,opioid overdose,polysubstance overdose,and carbon monoxide(CO)poisoning.Symptoms frequently include decreased level of consciousness,psychomotor agitation,cognitive decline,parkinsonism,and encephalopathy.Neuroimaging commonly revealed diffuse T2 hyperintensities in cerebral white matter,sometimes involving the basal ganglia and the globus pallidus.Magnetic resonance spectroscopy often showed decreased N-acetylaspartate,elevated choline,choline-to-creatinine ratio,and normal or elevated lactate.Treatment is often supportive,including amantadine,an antioxidant cocktail,and steroids.Hyperbaric oxygen therapy may be beneficial in those with CO poisoning.Parkinsonism was often treated with levodopa.Most of the patients had substantial recovery over the course of months and many cases had some residual neurocognitive deficits.CONCLUSION DPHLS remains a complex and multifaceted condition with various etiologies and clinical manifestations.Early recognition and appropriate management are crucial to improving patient outcomes.Future research should focus on standardizing diagnostic criteria,using advanced imaging techniques,and exploring therapeutic interventions to improve understanding and treatment of DPHLS.Conducting prospective cohort studies and developing biomarkers for early diagnosis and monitoring will be essential to advance patient care.
基金supported by the National Key Research and Development Program(2021YFC3002205)the Postgraduate Research and Innovation Program of Tianjin Municipal Education Commission(2022BKY113),China.
文摘Cardiac arrest(CA)is a critical condition in the field of cardiovascular medicine.Despite successful resuscitation,patients continue to have a high mortality rate,largely due to post CA syndrome(PCAS).However,the injury and pathophysiological mechanisms underlying PCAS remain unclear.Experimental animal models are valuable tools for exploring the etiology,pathogenesis,and potential interventions for CA and PCAS.Current CA animal models include electrical induction of ventricular fibrillation(VF),myocardial infarction,high potassium,asphyxia,and hemorrhagic shock.Although these models do not fully replicate the complexity of clinical CA,the mechanistic insights they provide remain highly relevant,including post-CA brain injury(PCABI),post-CA myocardial dysfunction(PAMD),systemic ischaemia/reperfusion injury(IRI),and the persistent precipitating pathology.Summarizing the methods of establishing CA models,the challenges encountered in the modeling process,and the mechanisms of PCAS can provide a foundation for developing standardized CA modeling protocols.
基金supported by the National Natural Science Foundation of China(Grant Nos.62076217,U21B2048 and U22B2037)the National Language Commission(ZDI145-71)the Blue Project of Jiangsu,the Top-level Talents Support Program,the Blue Project and Teaching Reform Project(YZUJX2023-D8)of Yangzhou University.
文摘1 Introduction The recent emergence of human-like language models like ChatGPT has raised concerns regarding the potential abuse of LLMs for malicious purposes[1,2].Detecting text generated by LLMs has become critically important[3].
文摘The effects of post heat treatment on the microstructure,aging kinetics,and room/elevated temperature mechanical properties of additively manufactured Inconel 718 superalloy were investigated.Scanning electron microscopy(SEM),electron backscattered diffraction(EBSD),and X-ray diffraction(XRD),as well as hardness,tensile,and creep testing were used for characterization.At temperatures higher than 1100°C,homogenization treatment resulted in the appearance of equiaxed grains by recrystallization and diminishing the dislocation density.The precipitation activation energy for the homogenized and aged condition was obtained as 203.2 kJ/mol,which was higher than the value of~160 kJ/mol for the as-built IN718 superalloy.Therefore,direct aging resulted in a faster aging response,which led to a significant improvement in tensile properties,as rationalized by the strengthening mechanisms.Direct aging treatment resulted in a higher elevated-temperature ultimate tensile strength(UTS)as well as the optimum creep life and the lowest minimum creep rate in comparison with other heat treatment routes,which were attributed to the presence of fine and uniformly dispersed strengthening precipitates in conjunction with the high dislocation density.
文摘Cardiac arrest is associated with high rates of mortality and significant long-term neurological disability in survivors.Timely and accurate assessment following successful resuscitation is critical for optimizing outcomes.Imaging plays a central role in this evaluation process,providing crucial insights into the etiology of arrest,the extent of cerebral and cardiac injury,and guiding both acute management and long-term prognostication.A structured,multimodal imaging approach utilizing tools such as computed tomography,magnetic resonance imaging,echocardiography,and angiography is increasingly recognized as es-sential in the post-cardiac arrest setting.This review aims to consolidate current evidence related to the use of various imaging modalities across neurological,cardiac and systemic contexts.Particular emphasis is placed on the prognostic value and optimal timing of neuroimaging,the detection of potentially reversible causes of arrest,such as coronary occlusion or pulmonary embolism,and the emerging role of whole-body imaging in evaluating patients with non-traumatic out-of-hospital cardiac arrest.
基金Guangdong Basic and Applied Basic Research Foundation under Grant Nos.2022A1515110561 and 2023A1515010072Natural Science Foundation of China under Grant Nos.52308488 and 52378499。
文摘High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of equipment.This study proposed a variable cross-section damped steel support frame(VCDFS)with viscous dampers to reduce seismic responses of both tall and low-rise electrical equipment.The VCDFS contains a trapezoidal damper layer to generate rocking motions,enabling the diagonal viscous dampers to dissipate seismic inputs.A theoretical model of post equipment with VCDFS is established,and an optimal design procedure is proposed.The analysis shows that the remaining static stiffness ratio λ_(k) is the key parameter that determines the effectiveness of the VCDFS.The VCDFS reduces the average displacement and stress response of a post insulator by 39.4%and 44.6%,respectively,together with a significant decrease in the dynamic amplification factor.Therefore,it is recommended to use the VCDFS instead of the conventional latticed-steel frame in earthquake zones.
基金supported by the National Natural Science Foundation of China(T2241028)STI2030-Major Projects[2021ZD0203000(2021ZD0203003)].
文摘Mental health disorders have emerged as a critical global health challenge,profoundly impacting individuals,communities,and societies worldwide.The prevalence of mental health problems has been steadily increasing,with~1 in 8 people,equivalent to 970 million individuals suffering from a mental disorder in 2019(https://vizhub.healthdata.org/gbd-results).Anxiety and depressive disorders are predominant,contributing significantly to the burden of mental health issues,according to the World Health Organization.The COVID-19 pandemic has further exacerbated this situation.It led to a notable upsurge in anxiety and major depressive disorders in 2020.Estimates indicate a 26%rise in anxiety and a 28%increase in depression within that year(https://www.who.int/publications/i/item/WHO-2019-nCoVSci_Brief-Mental_health-2022.1)[1].
基金supported by the National Key Research and Development Program of China(No.2023YFC2810700)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2021193)the Science and Technology Cooperation Project between Jilin Province and Chinese Academy of Sciences(No.2024SYHZ0032).
文摘This study analyzed through-thickness distribution of residual stress in a 106 mm ultra-thick TC4 titanium alloy electron beam welded(EBW)joint after post weld heat treatment(PWHT)using X-ray diffraction(XRD)and deep-hole drilling(DHD)methods,and investigated the microstructure and mechanical properties.During the PWHT at 600℃,a phase transformation(β→α)occurred in the EBW joint and affected the residual stress distribution and mechanical properties.The surface residual stress was mainly compressive stress,while the internal residual stress was mainly tensile stress in the welded joint.For the as-welded joint,the absolute value of surface residual stress was higher than the absolute value of internal residual stress.After PWHT,the residual stress in the treated joint was substantially reduced compared to the as-welded joint,particularly the surface stress,which relieved from−425 to−90 MPa.However,the residual stress relief effect had minimal positive impact on the internal region at 600℃.PWHT resulted in a shift of the joint fracture location from the fusion zone(FZ)to the base metal(BM),and therefore exerted no noticeable effect on the joint strength,but increased the joint elongation significantly.This study provides valuable insights into the regulation of residual stress distribution of ultra-thick titanium alloy plates.
基金support by the National Key R&D Program of China(No.2022YFB3402200)the Program of Shanghai Academic Research Leader(No.22XD1421600).
文摘Diffusion-bonded Ti_(2)AlNb-based alloys commonly present a low strength compared with the deformed or aged ones. In this study, the post heat treatment including solution and aging treatments is proposed to optimize the microstructure, contributing to strength improvement and appropriate ductility sacrifice. An available method by the introduction of fine size (both 20-100 nm) and a high fraction (59.7% and 13.7%) of O and α_(2) phases using both solution at 1000℃ for 1 h and aging at 750℃ for 5 h can result in excellent tensile strength (992 MPa and 858 MPa) at room temperature and 650℃, respectively, which increases 5.3% and 44.5% than that of as-received sample. The aging treatment can contribute to lamellar O and α2 grains precipitated from the B_(2) parent, which results in limited dislocation slip systems and slip spaces to resist plastic deformation. Moreover, the crack propagation and fracture surfaces are also comparatively analyzed to reveal the fracture behaviors in the samples with high and low strength. This study can provide a new method for the mechanical property optimization of the welded Ti_(2)AlNb alloys.
文摘The diagnosis and treatment processes for long COVID have been relatively slow to develop for several reasons,such as a lack of consensus about its definition among medical professionals and researchers,and restricted access to knowledge from the relevant pandemics of the past.Legacies of viral pandemics unfortunately do not include sufficient research on how the acute symptoms of infection evolved into chronic health conditions.More so,the idea of surviving a viral pandemic with long-lasting symptoms is not new,yet it is curiously disjointed as a medical concept throughout documented histories on the subject.Individuals with long-term conditions that are rooted in acute viral infections,such as COVID-19,require a coordinated system of care that includes comprehensive rehabilitation.This commentary will discuss the philosophical underpinnings of the historical scarcity of documented incidences of individuals with chronic virus symptoms and the need for a shift in post-viral infection treatment approaches.
文摘BACKGROUND Historically intraoperative drains were employed after pancreatic surgery but over the last decade,there has been debate over the routine usage of drains.AIM To assess the necessity of intra-abdominal drain placement,identify the most effective drain type,and determine the optimal timing for drain removal.METHODS A systematic review of electronic databases,including PubMed,MEDLINE,PubMed Central,and Google Scholar,was conducted using Medical Subject Headings and keywords until December 2023.From an initial pool of 1910 articles,48 were included after exclusion and screening.The primary outcomes analyzed were clinically relevant postoperative pancreatic fistula(CR-POPF),delayed gastric emptying(DGE),overall morbidity,and mortality.Subgroup analyses were performed for pancreaticoduodenectomy and distal pancreatectomy.RESULTS Routine use of drains is associated with a statistically significant increase in the risk of CR-POPF and DGE.Conversely,patients who did not have drains placed experienced a significant reduction in morbidity,readmission rates,and reoperations.No significant differences were observed between active and passive drain types.Early drain removal(<3 days)yielded favorable outcomes compared to delayed removal.CONCLUSION Analysis of randomized controlled trials and cohort studies did not demonstrate an advantage of routine drain placement following pancreatic resection,potentially contributing to increased morbidity and mortality.The decision to use drains should be left to the discretion of the operating surgeon.However,early drain removal can substantially reduce morbidity.
文摘Chak-hao,the Forbidden Rice from Manipur,India,is an aromatic,purplish-black rice variety that has been awarded a geographical indication tag to preserve and promote its traditional cultivation in Manipur,India.Although Chak-hao is a hardy landrace with field tolerance to biotic stress,its grains are highly susceptible to storage pest infestations,particularly those caused by the rice weevil(Sitophilus oryzae).This severely compromises its commercial storage quality,as pest damage reduces both nutritional value and quantity.
文摘This article discusses the evolving real-world practice using nitazoxanide,nonsteroidal anti-inflammatory drugs(NSAIDs)and/or azithromycin(Kelleni’s protocol)to manage the evolving manifestations of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron EG.5.1,its descendant HV.1 as well as BA.2.86 and its descendant JN.1 subvariants in Egypt in 2024.These subvariants are well-known for their highly evolved immune-evasive properties and the manifestations include some peculiar manifestations as persistent cough besides high fever in young children as well as high fever,persistent severe cough,change of voice,loss of taste and smell,epigastric pain,nausea,vomiting,diarrhea,generalized malaise and marked bone aches in adults including the high-risk groups.It’s suggested that the ongoing SARS-CoV-2 evolution is continuing to mostly affect the high-risk groups of patients,to some of whom we’ve also successfully prescribed nitazoxanide and/or NSAIDs for post-exposure prophylaxis of all household contacts.We also continue to recommend starting the immune-modulatory antiviral Kelleni’s protocol as soon as possible in the course of infection and adjusting it in a personalized manner to be more aggressive from the beginning for the high risk patients,at least until the currently encountered surge of infections subsides.
基金supported by grants from the National Natural Science Foundation of China (82070408)the Traditional Chinese Medicine Science and Technology Project of Zhejiang Province (2023ZL496)。
文摘Background Quantitative flow ratio(QFR) holds significant value in guiding drug-coated balloon(DCB) treatment and enhancing outcomes. However, the predictive capability of post-angioplasty QFR for long-term clinical events in patients with de novo lesions who receive DCB treatment remains uncertain. The aim of this study was to explore the potential significance of post-angioplasty QFR measurements in predicting clinical outcomes in patients underwent DCB treatment for de novo lesions.Methods Patients who underwent DCB-only intervention for de novo lesions were enrolled. QFR was conducted after DCB treatment. The patients were then categorized based on post-angioplasty QFR. The primary endpoint was major adverse cardiac events(MACE), encompassing all-cause death, cardiovascular death, nonfatal myocardial infarction, stroke, and target vessel revascularization.Results A total of 553 patients with 561 lesions were included. The median follow-up period was 505 days, during which 66(11.8%) MACEs occurred. Based on post-procedural QFR grouping, there were 259 cases in the high QFR group(QFR > 0.93) and302 cases in the low QFR group(QFR ≤ 0.93). Kaplan-Meier analysis revealed a significantly higher cumulative incidence of MACE in the low QFR group(log-rank P = 0.004). The multivariate Cox proportional hazards model demonstrated a significant inverse correlation between QFR and the occurrence of MACEs(HR = 0.522, 95%CI: 0.289-0.942, P = 0.031). Landmark analysis indicated that high QFR had a significant reducing effect on the cumulative incidence of MACEs within 1 year(log-rank P = 0.016)and 1-5 years(log-rank P = 0.026).Conclusions In patients who underwent DCB-only treatment for de novo lesions, higher post-procedural QFR values(> 0.93)were identified as an independent protective factor against adverse prognosis.
文摘A conventional non-computerized numerical control （CNC） machine is updated by mounting a six degree-of-free （DOF） parallel mechanism on it, thus obtaining a new CNC one. The structure of this CNC milling machine is introduced, and the workpiece locating system and the post processing system of the cutter location （CL） data file are analyzed. The new machine has advantages of low costs, simple structure, good rigidity, and high precision. It is easy to be transformed and used to process the workpiece with a complex surface.
文摘This paper discusses some aspects of finite element computation,such as the automatic generation of finite element ,refinement of mesh,process of node density, distribution of load,optimum design and the drawing of stress contour, and describes the developing process of software for a planar 8 node element.
文摘The observational line of sight velocity fields of a large post flare loop(PFL) system on August 17,1989 were derived based on “multi cloud model” (MCM) method from the Hβ spectral data obtained with the two dimensional Multi Waveband Spectra Spectro Helio Graph (MW SSHG) at Yunnan Observatory. In order to explain the fundamental features of the velocity fields observed,an assumption and approximation to be taken into account that the matter within a loop system rises up from the loop foot to the loop top along the loop leg in a helical magnetic line under the combined action of solar gravity, magnetic stress and a gradient of atmospheric pressure in the loop system, and a theoretical velocity field of the loop system was calcuated with the aid of MHD theory. From a comparison of both velocity fields, it is found that the computed velocity field is basically similar with the observed one. It indicates that the assumption and approximation mentioned above are suitable basically.
基金Supported by Education and Teaching Reform Project of the First Clinical College of Chongqing Medical University,No.CMER202305Program for Youth Innovation in Future Medicine,Chongqing Medical University,No.W0138.
文摘We focus on the importance and necessity of post-competency-based training in medical education alongside its current challenges and opportunities.Integrating post competency training into standardized educational frameworks is increasingly recognized as a critical component of preparing residents and postgraduates for real-world clinical practice.Post competency training represents a commitment to excellence in medical education,striving to produce competent,skilled practitioners to meet the challenges of modern healthcare.
