In this study,microstructure and mechanical behavior of two types of Mg-based bimetal plates with a high formability sleeve were systematically studied,with a great emphasis on the effect of the interface characterist...In this study,microstructure and mechanical behavior of two types of Mg-based bimetal plates with a high formability sleeve were systematically studied,with a great emphasis on the effect of the interface characteristic and the sleeve fraction on the plasticity of composite plates.The rule of mixtures(ROM)for elongation was also addressed.The results show that when there is no or thin diffusion layer with thickness of about 3μm,Mg-based bimetal plates have a good plasticity with elongation of about 19-24%,and the ROM predicted elongations are very close to the experimental ones.In contrast,with a diffusion layer about 95-155μm thick,Mg-based bimetal plates exhibit a poor plasticity with elongation of about 11-17%,and the experimental elongations largely deviate from the ROM predictions.The plasticity of Mg-based bimetal plates increases with increasing sleeve fraction.This study provides new insights on the plastic deformation of Mg-based bimetal composites with a high formability sleeve.展开更多
The effects of hydro co-extrusion on the microstructure changes of aluminum hybrid duo-cast Al 3003/Al 4004 clad materials were studied. The specimen of duo-cast Al 3003/Al 4004 clad materials was in circle shape, and...The effects of hydro co-extrusion on the microstructure changes of aluminum hybrid duo-cast Al 3003/Al 4004 clad materials were studied. The specimen of duo-cast Al 3003/Al 4004 clad materials was in circle shape, and was composed of Al 3003(outside) and Al 4004(inside) materials. The specimen was extruded by the hydro co-extrusion equipment. The manufacturing conditions of the specimen were 423 K in temperature and 5 in extrusion ratio. The dimensions of the specimen were 80 mm in diameter of the Al 4004 material and 35 mm in thickness of the Al 3003 material before the hydro co-extrusion process, and 30 mm in diameter and about 5 mm in thickness after the extrusion process, respectively. The microstructure and the hardness for two specimens were investigated. The hardness value of cross section in the duo-cast Al 3003/Al 4004 clad materials before the extrusion process was increased in form of the parabola toward the center. However, after the extrusion process, it was almost constant in the portion of Al 4004 material. Lots of big voids above 1 mm in diameter in the specimen existed in the interfacing region of Al 3003 and Al 4004 materials before the extrusion process. These big voids disappeared after the process of hydro co-extrusion.展开更多
Encapsulation confers protection to substances as essential oils from processes like oxidation, evaporation or uncontrolled release. In this study almond oil capsules were obtained by co-extrusion/gelling technique. C...Encapsulation confers protection to substances as essential oils from processes like oxidation, evaporation or uncontrolled release. In this study almond oil capsules were obtained by co-extrusion/gelling technique. Chitosan was used as shell material and sodium triphosphate pentabasic as cross linking agent. Different encapsulation process variables were studied: cross-linker concentration, nozzles size and potential. Optical microscopy was used to determine the capsules morphology and degradability tests were performed in order to study capsules degradation over time. Results showed that nozzles size and cross linking concentration are key variables to consider in the encapsulation process. Degradability tests showed rapid weight loss.展开更多
An essential oil is the volatile lipophilic component extracted from plants. Microencapsulation systems protect the essential oil from degradation and evaporation, and at the same time allow a sustained release. This ...An essential oil is the volatile lipophilic component extracted from plants. Microencapsulation systems protect the essential oil from degradation and evaporation, and at the same time allow a sustained release. This work analyzed and characterized the rosemary essential oil microcapsules prepared by co-extrusion technique using alginate as wall material and calcium chloride as cross linker. Several instrumental techniques were used: optical microscopy, coulter counter, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), termogravimetric analysis (TGA), spectrophotometry, antimicrobial test and chromatography. Results show that rosemary oil has pesticidal properties, and its microencapsulation allows knowing that these properties remain inside the microcapsules.展开更多
The purpose of this paper is to examine the effect of processing parameters and subsequent heat treatments on the microstructures and bonding strengths of Ti-6Al-4V/AA1050 laminations formed via a non-equal channel la...The purpose of this paper is to examine the effect of processing parameters and subsequent heat treatments on the microstructures and bonding strengths of Ti-6Al-4V/AA1050 laminations formed via a non-equal channel lateral co-extrusion process.The microstructural evolution and growth mechanism in the diffusion layer were discussed further to optimize the bonding quality by appropriately adjusting process parameters.Scanning electron microscopes(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)were used to characterize interfacial diffusion layers.The shear test was used to determine the mechanical properties of the interfacial diffusion layer.The experimental results indicate that it is possible to co-extrusion Ti-6Al-4V/AA1050 compound profiles using non-equal channel lateral co-extrusion.Different heat treatment processes affect the thickness of the diffusion layer.When the temperature and time of heat treatment increase,the thickness of the reaction layers increases dramatically.Additionally,the shear strength of the Ti-6Al-4V/AA1050 composite interface is proportional to the diffusion layer thickness.It is observed that a medium interface thickness results in superior mechanical performance when compared to neither a greater nor a lesser interface thickness.Microstructural characterization of all heat treatments reveals that the only intermetallic compound observed in the diffusion layers is TiAl_(3).Due to the inter-diffusion of Ti and Al atoms,the TiAl_(3) layer grows primarily at AA1050/TiAl_(3) interfaces.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
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
Deep in the Tengger Desert of Inner Mongolia autonomous region,surrounded by sand as far as the eye can see,lies the world's loneliest post office.Measuring only 15 square meters,the wooden post office doesn't...Deep in the Tengger Desert of Inner Mongolia autonomous region,surrounded by sand as far as the eye can see,lies the world's loneliest post office.Measuring only 15 square meters,the wooden post office doesn't get too many visitors anyway.But after being abandoned for over 35 years,it actually doesn't look half bad.展开更多
Polyvinyl chloride(PVC)is one of the most widely used plastic materials worldwide,particularly in long-life applications such as construction materials.However,recycling options for PVC waste remain limited,as convent...Polyvinyl chloride(PVC)is one of the most widely used plastic materials worldwide,particularly in long-life applications such as construction materials.However,recycling options for PVC waste remain limited,as conventional methods often degrade material quality or generate environmentally hazardous byproducts.In this study,we demonstrate an efficient process to convert PVC into new polymers with variable aromatic groups,using triethylsilane as the reductant in different solvents.This approach enables the production of polymers analogous to functionalized polyethylene(PE),which are typically challenging to obtain through conventional copolymerization or direct post-modification of C-H bonds in PE.The resulting polymers exhibit tunable thermal and mechanical properties depending on the introduced aromatic groups,which not only enhance the sustainable valorization of PVC waste,but also provide an opportunity for the synthesis of new functionalized polymers.展开更多
On January 7,2025,a 6.8-magnitude earthquake struck Dingri County,Xigaze City,Xizang.On March 3,efforts for post-disaster reconstruction were initiated.By October 31,all newly built,repaired,and reinforced houses had ...On January 7,2025,a 6.8-magnitude earthquake struck Dingri County,Xigaze City,Xizang.On March 3,efforts for post-disaster reconstruction were initiated.By October 31,all newly built,repaired,and reinforced houses had been fully completed and handed over to residents in the earthquake-affected areas of Dingri and surrounding areas,enabling them to move into new homes within the same year they experienced the impact.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
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
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
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
The year 2025 marks the 80th anniversary of the founding of the United Nations(UN).As the most universal,representative,and authoritative intergovernmental international organization in the world,the UN serves as the ...The year 2025 marks the 80th anniversary of the founding of the United Nations(UN).As the most universal,representative,and authoritative intergovernmental international organization in the world,the UN serves as the core platform for upholding multilateralism and a crucial cornerstone of the international order.In recent years,the UN’s ability to address global challenges is tested.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
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
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
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
基金supported by the National Key Research and Development Program of China (No.2022YFB3708400)the Guangdong Major Project of Basic and Applied Basic Research (No.2020B0301030006)+3 种基金the Guangdong Academy of Science Fund (No.2020GDASYL-20200101001,2021GDASYL-20210102002,2021GDASYL-20210103103)the National Natural Science Foundation of China (Nos.51905111 and 12002092)the Youth Talent Support Programme of Guangdong Provincial Association for Science and Technology (No.SKXRC202301)the Natural Science Foundation of Guangdong Province (Nos.2021A1515011730 and 2019A1515012096).
文摘In this study,microstructure and mechanical behavior of two types of Mg-based bimetal plates with a high formability sleeve were systematically studied,with a great emphasis on the effect of the interface characteristic and the sleeve fraction on the plasticity of composite plates.The rule of mixtures(ROM)for elongation was also addressed.The results show that when there is no or thin diffusion layer with thickness of about 3μm,Mg-based bimetal plates have a good plasticity with elongation of about 19-24%,and the ROM predicted elongations are very close to the experimental ones.In contrast,with a diffusion layer about 95-155μm thick,Mg-based bimetal plates exhibit a poor plasticity with elongation of about 11-17%,and the experimental elongations largely deviate from the ROM predictions.The plasticity of Mg-based bimetal plates increases with increasing sleeve fraction.This study provides new insights on the plastic deformation of Mg-based bimetal composites with a high formability sleeve.
基金supported by the project of Fundamental Materials Development funded by the Korean Ministry of Knowledge Economy
文摘The effects of hydro co-extrusion on the microstructure changes of aluminum hybrid duo-cast Al 3003/Al 4004 clad materials were studied. The specimen of duo-cast Al 3003/Al 4004 clad materials was in circle shape, and was composed of Al 3003(outside) and Al 4004(inside) materials. The specimen was extruded by the hydro co-extrusion equipment. The manufacturing conditions of the specimen were 423 K in temperature and 5 in extrusion ratio. The dimensions of the specimen were 80 mm in diameter of the Al 4004 material and 35 mm in thickness of the Al 3003 material before the hydro co-extrusion process, and 30 mm in diameter and about 5 mm in thickness after the extrusion process, respectively. The microstructure and the hardness for two specimens were investigated. The hardness value of cross section in the duo-cast Al 3003/Al 4004 clad materials before the extrusion process was increased in form of the parabola toward the center. However, after the extrusion process, it was almost constant in the portion of Al 4004 material. Lots of big voids above 1 mm in diameter in the specimen existed in the interfacing region of Al 3003 and Al 4004 materials before the extrusion process. These big voids disappeared after the process of hydro co-extrusion.
文摘Encapsulation confers protection to substances as essential oils from processes like oxidation, evaporation or uncontrolled release. In this study almond oil capsules were obtained by co-extrusion/gelling technique. Chitosan was used as shell material and sodium triphosphate pentabasic as cross linking agent. Different encapsulation process variables were studied: cross-linker concentration, nozzles size and potential. Optical microscopy was used to determine the capsules morphology and degradability tests were performed in order to study capsules degradation over time. Results showed that nozzles size and cross linking concentration are key variables to consider in the encapsulation process. Degradability tests showed rapid weight loss.
基金The autors thank IVACE(Institut Valenciàde Competitivitat Empresarial,Spain)FEDER(Fondo Europeo de Desarrollo Regional,Europe)for the financial support
文摘An essential oil is the volatile lipophilic component extracted from plants. Microencapsulation systems protect the essential oil from degradation and evaporation, and at the same time allow a sustained release. This work analyzed and characterized the rosemary essential oil microcapsules prepared by co-extrusion technique using alginate as wall material and calcium chloride as cross linker. Several instrumental techniques were used: optical microscopy, coulter counter, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), termogravimetric analysis (TGA), spectrophotometry, antimicrobial test and chromatography. Results show that rosemary oil has pesticidal properties, and its microencapsulation allows knowing that these properties remain inside the microcapsules.
基金the financial support by the National Natural Science Foundation of China(No.12272094,51805087 and 51705080)the Natural Science Foundation of Fujian Province of China(No.2022J01541)。
文摘The purpose of this paper is to examine the effect of processing parameters and subsequent heat treatments on the microstructures and bonding strengths of Ti-6Al-4V/AA1050 laminations formed via a non-equal channel lateral co-extrusion process.The microstructural evolution and growth mechanism in the diffusion layer were discussed further to optimize the bonding quality by appropriately adjusting process parameters.Scanning electron microscopes(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)were used to characterize interfacial diffusion layers.The shear test was used to determine the mechanical properties of the interfacial diffusion layer.The experimental results indicate that it is possible to co-extrusion Ti-6Al-4V/AA1050 compound profiles using non-equal channel lateral co-extrusion.Different heat treatment processes affect the thickness of the diffusion layer.When the temperature and time of heat treatment increase,the thickness of the reaction layers increases dramatically.Additionally,the shear strength of the Ti-6Al-4V/AA1050 composite interface is proportional to the diffusion layer thickness.It is observed that a medium interface thickness results in superior mechanical performance when compared to neither a greater nor a lesser interface thickness.Microstructural characterization of all heat treatments reveals that the only intermetallic compound observed in the diffusion layers is TiAl_(3).Due to the inter-diffusion of Ti and Al atoms,the TiAl_(3) layer grows primarily at AA1050/TiAl_(3) interfaces.
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 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.
文摘Deep in the Tengger Desert of Inner Mongolia autonomous region,surrounded by sand as far as the eye can see,lies the world's loneliest post office.Measuring only 15 square meters,the wooden post office doesn't get too many visitors anyway.But after being abandoned for over 35 years,it actually doesn't look half bad.
基金the Beijing Natural Science Foundation(Z240029)the National Natural Science Foundation of China(22472004)+2 种基金China National Petroleum Corporation-Peking University Strategic Cooperation Project of Fundamental Researchthe New Cornerstone Science Foundationsupport from the Tencent Foundation through the Xplorer Prize.
文摘Polyvinyl chloride(PVC)is one of the most widely used plastic materials worldwide,particularly in long-life applications such as construction materials.However,recycling options for PVC waste remain limited,as conventional methods often degrade material quality or generate environmentally hazardous byproducts.In this study,we demonstrate an efficient process to convert PVC into new polymers with variable aromatic groups,using triethylsilane as the reductant in different solvents.This approach enables the production of polymers analogous to functionalized polyethylene(PE),which are typically challenging to obtain through conventional copolymerization or direct post-modification of C-H bonds in PE.The resulting polymers exhibit tunable thermal and mechanical properties depending on the introduced aromatic groups,which not only enhance the sustainable valorization of PVC waste,but also provide an opportunity for the synthesis of new functionalized polymers.
文摘On January 7,2025,a 6.8-magnitude earthquake struck Dingri County,Xigaze City,Xizang.On March 3,efforts for post-disaster reconstruction were initiated.By October 31,all newly built,repaired,and reinforced houses had been fully completed and handed over to residents in the earthquake-affected areas of Dingri and surrounding areas,enabling them to move into new homes within the same year they experienced the impact.
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.
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 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.
文摘The year 2025 marks the 80th anniversary of the founding of the United Nations(UN).As the most universal,representative,and authoritative intergovernmental international organization in the world,the UN serves as the core platform for upholding multilateralism and a crucial cornerstone of the international order.In recent years,the UN’s ability to address global challenges is tested.
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].
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.
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.
