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Primary rectal signet ring cell carcinoma with peritoneal dissemination and gastric secondaries 被引量:1
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作者 Hsien-Lin Sim Kok-Yang Tan +1 位作者 Pak-Leng Poon Anton Cheng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第13期2118-2120,共3页
Disseminated signet ring cell carcinomas frequently arise from the stomach. However, primaries in the colon and rectum have also been reported. We present a 68 year old lady who presented with a change in her bowel ha... Disseminated signet ring cell carcinomas frequently arise from the stomach. However, primaries in the colon and rectum have also been reported. We present a 68 year old lady who presented with a change in her bowel habit. Colonoscopy showed a stenosing rectal tumour at 7 cm to 8 cm from the anal verge. Multiple scattered ulcers were also noted along the entire length of the colon. Biopsy of the lesions revealed signet ring cell adenocarcinoma. Gastroscopy showed multiple nodules with ulceration over several areas of the stomach which were similar in appearance to the colonic lesions. However, no primary tumour of the stomach was seen. Biopsy of the gastric lesions also showed signet ring cell adenocarcinoma. Computed tomography scan of the abdomen and pelvis revealed circumferential tumour at the rectosigmoid junction with possible invasion into the left ischiorectal fossa. The overall picture was that of a primary rectal signet ring cell carcinoma with peritoneal dissemination. The patient was referred for palliative chemotherapy in view of the disseminated disease. In the present report, we discuss this interesting pathological entity and review the role of various histolological techniques in helping to identify the primary tumor. 展开更多
关键词 Signet ring cell carcinoma Colorectal tumour Peritoneal dissemination Gastric secondaries
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Impact Craters with Circular and Isolated Secondary Craters on the Continuous Secondaries Facies on the Moon 被引量:1
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作者 Shangzhe Zhou Zhiyong Xiao Zuoxun Zeng 《Journal of Earth Science》 SCIE CAS CSCD 2015年第5期740-745,共6页
On airless bodies such as the Moon and Mercury, secondary craters on the continuous secondaries facies of fresh craters mostly occur in chains and clusters. They have very irregular shapes. Secondaries on the continuo... On airless bodies such as the Moon and Mercury, secondary craters on the continuous secondaries facies of fresh craters mostly occur in chains and clusters. They have very irregular shapes. Secondaries on the continuous secondaries facies of some Martian and Mercurian craters are more isolated from each other in distribution and are more circular in shape, probably due to the effect of target properties on the impact excavation process. This paper studies secondaries on the continuous secondaries facies of all fresh lunar complex craters using recently-obtained high resolution images. After a global search, we find that 3 impact craters and basins on the Moon have circular and isolated secondaries on the continuous secondaries facies similar to those on Mercury: the Orientale basin, the Antoniadi crater, and the Compton crater. The morphological differences between such special secondaries and typical lunar secondaries are quantitatively compared and analyzed. Our preliminary analyses suggest that the special secondaries were probably caused by high temperature gradients within the local targets when these craters and basins formed. The high-temperature of the targets could have affected the impact excavation process by causing higher ejection angles, giving rise to more scattered circular secondaries. 展开更多
关键词 MOON impact cratering secondary craters comparative planetology
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Microstructure and Properties of Mg/Fe Dissimilar Metal Joints Fabricated by Magnetic Pulse Welding
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作者 Xie Jilin Li Shimeng +3 位作者 Wang Yaping Liu Dongya Liu Xiaofang Chen Yuhua 《稀有金属材料与工程》 北大核心 2026年第1期67-77,共11页
Dissimilar AZ31B magnesium alloy and DC56D steel were welded via AA1060 aluminum alloy by magnetic pulse welding.The effects of primary and secondary welding processes on the welded interface were comparatively invest... Dissimilar AZ31B magnesium alloy and DC56D steel were welded via AA1060 aluminum alloy by magnetic pulse welding.The effects of primary and secondary welding processes on the welded interface were comparatively investigated.Macroscopic morphology,microstructure,and interfacial structure of the joints were analyzed using scanning electron microscope,energy dispersive spectrometer,and X-ray diffractometer(XRD).The results show that magnetic pulse welding of dissimilar Mg/Fe metals is achieved using an Al interlayer,which acts as a bridge for deformation and diffusion.Specifically,the AZ31B/AA1060 interface exhibits a typical wavy morphology,and a transition zone exists at the joint interface,which may result in an extremely complex microstructure.The microstructure of this transition zone differs from that of AZ31B magnesium and 1060 Al alloys,and it is identified as brittle intermetallic compounds(IMCs)Al_(3)Mg_(2) and Al_(12)Mg_(17).The transition zone is mainly distributed on the Al side,with the maximum thickness of Al-side transition layer reaching approximately 13.53μm.Incomplete melting layers with varying thicknesses are observed at the primary weld interface,while micron-sized hole defects appear in the transition zone of the secondary weld interface.The AA1060/DC56D interface is mainly straight,with only a small number of discontinuous transition zones distributed intermittently along the interface.These transition zones are characterized by the presence of the brittle IMC FeAl_(3),with a maximum thickness of about 4μm. 展开更多
关键词 magnetic pulse welding mechanical properties MICROSTRUCTURE fracture morphology primary and secondary welding
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Etiology and clinical analysis of secondary glaucoma:a single-center study from northwest China
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作者 Ying Liu Jie Yang +6 位作者 Rui-Xue Zhang Yao Lu Wei Sang Jin-Wei Xi Jun Jia Dan-Ping Guo Yuan He 《International Journal of Ophthalmology(English edition)》 2026年第1期69-76,共8页
AIM:To investigate the etiology and clinical characteristics of hospitalized secondary glaucoma(SG)patients in northwestern China.METHODS:A cross-sectional study was conducted involving SG patients hospitalized betwee... AIM:To investigate the etiology and clinical characteristics of hospitalized secondary glaucoma(SG)patients in northwestern China.METHODS:A cross-sectional study was conducted involving SG patients hospitalized between July 2024 and January 2025.Clinical data were collected,including medical history,best-corrected visual acuity(BCVA),intraocular pressure(IOP),slit-lamp examination,gonioscopic findings,and fundus examination.Demographic characteristics,etiological factors,and treatment modalities were analyzed.RESULTS:A total of 67 patients(82 eyes)were enrolled,aged 7 to 90y.Males accounted for 54.0%(36/67),and 22.4%(15/67)of patients had bilateral involvement.The predominant etiologies of SG were neovascular glaucoma(NVG;25.4%),traumatic glaucoma(23.9%),uveitic glaucoma(20.9%),and lens-induced glaucoma(14.9%),collectively accounting for 85.1%of all cases.The peak age-specific incidence occurred in the 50-59 years age group(32.8%,22/67),while NVG was prevalent across the 40-79 years age range.IOP of the 82 affected eyes was stratified into five severity tiers:22-29 mm Hg(15 eyes,18.3%),30-39 mm Hg(14 eyes,17.1%),40-49 mm Hg(13 eyes,15.9%),50-59 mm Hg(20 eyes,24.4%),and≥60 mm Hg(20 eyes,24.4%).The overall mean IOP was 45.2±12.3 mm Hg,indicating a significant pathological elevation.Surgical intervention was required in 46.3%of cases,predominantly for NVG,lensinduced glaucoma,and traumatic glaucoma—conditions prone to rapid IOP elevation.The etiologies with the highest surgical intervention rates were malignant glaucoma,pigmentary glaucoma,lens-induced glaucoma,and NVG.In contrast,uveitic glaucoma cases were primarily managed with targeted anti-inflammatory therapy,which effectively controlled IOP in the early disease stages and potentially obviated the need for surgery.CONCLUSION:This study identifies NVG,traumatic glaucoma,uveitic glaucoma,and lens-induced glaucoma as the four leading etiologies of SG in Northwestern China.These findings emphasize the critical need for targeted prevention strategies and evidence-based health education programs among high-risk populations.Implementation of such initiatives will improve early detection,enable ophthalmologists to deliver timely therapeutic interventions,and ultimately reduce preventable vision loss in this region. 展开更多
关键词 secondary glaucoma EPIDEMIOLOGICAL northwestern China ETIOLOGY
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Impact of temperature on the biogenic volatile organic compound(BVOC)emissions in China:A review
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作者 Yiming Yang Fengbin Sun +8 位作者 Yusheng Chen Shiyue Yang Yuan Dai Yiming Qin Ning Zhang Zhifeng Shu Han Yan Xinlei Ge Junfeng Wang 《Journal of Environmental Sciences》 2026年第1期649-660,共12页
Temperature has a substantial impact on the emission of biogenic volatile organic compounds(BVOCs).Moder-ate warm temperatures,e.g.,30–40°C,could boost plant metabolism,increasing BVOC emissions.Against the back... Temperature has a substantial impact on the emission of biogenic volatile organic compounds(BVOCs).Moder-ate warm temperatures,e.g.,30–40°C,could boost plant metabolism,increasing BVOC emissions.Against the backdrop of global warming,plants emit more BVOCs to cope with thermal stress,leading to elevated concen-trations of tropospheric ozone(O_(3))and secondary organic aerosols(SOA).In recent years,a considerable body of research has explored the interaction between tree species and BVOCs under the influence of various environ-mental factors.Although many studies have examined explored the temperature dependence of BVOC emissions in the past,few studies have conducted a comprehensive and in-depth investigation into the impacts of tempera-ture.This review summarizes the relevant studies on BVOCs in the past decade,including the main biosynthetic pathways,emission observation techniques and emission inventories,as well as how temperature affects isoprene and monoterpene emission rates and the formation of O_(3) and SOA.Our work offers a theoretical foundation and guidance for future efforts to advance the comprehension of BVOC emission characteristics and develop strategies to mitigate secondary pollution. 展开更多
关键词 TEMPERATURE Biogenic volatile organic compounds ISOPRENE OZONE Secondary organic aerosol
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Tropical cyclone secondary eyewall width modulation:Differential impacts of surface environmental wind-vertical shear alignment and counter-alignment configurations
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作者 Yingying Zheng Qingqing Li Yufan Dai 《Atmospheric and Oceanic Science Letters》 2026年第1期7-13,共7页
This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shea... This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shear(VWS),using idealized numerical experiments.Results reveal that the SE develops greater radial extent when surface winds align with VWS compared to counter-aligned conditions.In alignment configurations,shear-enhanced surface winds on the right flank amplify surface enthalpy fluxes,thereby elevating boundary-layer entropy within the downshear outer-core region.Subsequently,more vigorous outer rainbands develop,inducing marked acceleration of tangential winds in the outer core preceding SE formation.The resultant radial expansion of supergradient winds near the boundary-layer top triggers widespread convective activity immediately beyond the inner core.Progressive axisymmetrization of this convective forcing ultimately generates an expansive SE structure. 展开更多
关键词 Tropical cyclone Secondary eyewall width Precipitation Vertical wind shear
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Mitophagy:A key regulator in the pathophysiology and treatment of spinal cord injury
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作者 Qiuyang Gu Shengye Yuan +7 位作者 Yumei An Wenyue Sun Mingyuan Xu Mengchun Xue Xianzhe Li Chao Liu Haiyan Shan Mingyang Zhang 《Neural Regeneration Research》 2026年第4期1396-1408,共13页
Mitophagy is closely associated with the pathogenesis of secondary spinal cord injury.Abnormal mitophagy may contribute significantly to secondary spinal cord injury,leading to the impaired production of adenosine tri... Mitophagy is closely associated with the pathogenesis of secondary spinal cord injury.Abnormal mitophagy may contribute significantly to secondary spinal cord injury,leading to the impaired production of adenosine triphosphate,ion imbalance,the excessive production of reactive oxygen species,neuroinflammation,and neuronal cell death.Therefore,maintaining an appropriate balance of mitophagy is crucial when treating spinal cord injury,as both excessive and insufficient mitophagy can impede recovery.In this review,we summarize the pathological changes associated with spinal cord injury,the mechanisms of mitophagy,and the direct and indirect relationships between mitophagy and spinal cord injury.We also consider therapeutic approaches that target mitophagy for the treatment of spinal cord injury,including ongoing clinical trials and other innovative therapies,such as use of stem cells,nanomaterials,and small molecule polymers.Finally,we highlight the current challenges facing this field and suggest potential directions for future research.The aim of our review is to provide a theoretical reference for future studies targeting mitophagy in the treatment of spinal cord injury. 展开更多
关键词 ATP production disorders cell death mitochondria MITOPHAGY NEUROINFLAMMATION NEUROPROTECTION oxidative stress secondary injury spinal cord injury treatment
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Characterization,sources and reactivity of carbonyl volatile organic compounds in North China:Based on long-term observations
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作者 Ziyan Chen Kaitao Chen +4 位作者 Xingru Li Rongjie Li Zheng Li Bingyu Xiao Gehui Wang 《Journal of Environmental Sciences》 2026年第1期797-808,共12页
Carbonyl compounds play a pivotal role in the formation of secondary pollutants such as O_(3) and SOA,signifi-cantly impacting air quality and human health.This study extended the observation period compared to previo... Carbonyl compounds play a pivotal role in the formation of secondary pollutants such as O_(3) and SOA,signifi-cantly impacting air quality and human health.This study extended the observation period compared to previous research,providing a long-term perspective on carbonyl compound variations and their environmental implica-tions.Atmospheric observations were conducted at Beijing(BJ)and Xianghe(XH)during the summer and winter months of 2018,2019,and 2023 to study the sources and impacts of carbonyl compounds in typical urban areas and peri‑urban areas.Notably,concentrations in the summer of 2023 increased compared to 2018 and 2019.The predominant carbonyl compounds—formaldehyde,acetaldehyde,and acetone—accounted for over 60%of the total.The mean values of OFP in BJ ranged from 18.55 to 58.61μg/m3,lower than those in XH(29.82 to 65.48μg/m3),with formaldehyde and acetaldehyde contributing over 80%of the total.SOAP exhibited a similar pattern,with values in XH(69.21 to 508.55μg/m3)significantly exceeding those in BJ(34.47 to 159.78μg/m3).The PMF model highlighted vehicle exhaust,secondary pollution,and biomass combustion as major sources of carbonyl compounds,emphasizing differences in source contributions between the two regions.This study’s com-parative analysis over different years and locations provides new insights into the dynamic changes in carbonyl compounds and their environmental importance.These results not only reinforce the importance of carbonyl compounds regulation but also offer a valuable reference for evaluating and refining emission control strategies during this period. 展开更多
关键词 Carbonyl compounds Ozone formation potential Secondary organic aerosol formation potential Source resolution
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Distribution of Tobacco Retail Outlets around Secondary Schools and Association with Students'Smoking Behavior in Beijing,2024
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作者 Mingxin Qi Xiaokai Jia +2 位作者 Ruiran Liu Yingchen Sang Lin Xiao 《Biomedical and Environmental Sciences》 2026年第1期111-115,共5页
Adolescent smoking constitutes a critical public health challenge as early initiation increases the risk of premature mortality and smoking-related chronic diseases due to longer exposure and higher cumulative tobacco... Adolescent smoking constitutes a critical public health challenge as early initiation increases the risk of premature mortality and smoking-related chronic diseases due to longer exposure and higher cumulative tobacco use^([1]).Adolescents are especially prone to developing persistent smoking habits,with many adult smokers having started before the age of 18.In China,16.7%of secondary school students have tried smoking and 4.7%are current smokers,highlighting the critical need for targeted tobacco control interventions among the youth. 展开更多
关键词 tobacco retail outlets chronic diseases secondary schools public health premature mortality targeted tobacco control int targeted interventions adolescent smoking
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T cell interactions with microglia in immune-inflammatory processes of ischemic stroke 被引量:7
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作者 Yuxiao Zheng Zilin Ren +8 位作者 Ying Liu Juntang Yan Congai Chen Yanhui He Yuyu Shi Fafeng Cheng Qingguo Wang Changxiang Li Xueqian Wang 《Neural Regeneration Research》 SCIE CAS 2025年第5期1277-1292,共16页
The primary mechanism of secondary injury after cerebral ischemia may be the brain inflammation that emerges after an ischemic stroke,which promotes neuronal death and inhibits nerve tissue regeneration.As the first i... The primary mechanism of secondary injury after cerebral ischemia may be the brain inflammation that emerges after an ischemic stroke,which promotes neuronal death and inhibits nerve tissue regeneration.As the first immune cells to be activated after an ischemic stroke,microglia play an important immunomodulatory role in the progression of the condition.After an ischemic stroke,peripheral blood immune cells(mainly T cells)are recruited to the central nervous system by chemokines secreted by immune cells in the brain,where they interact with central nervous system cells(mainly microglia)to trigger a secondary neuroimmune response.This review summarizes the interactions between T cells and microglia in the immune-inflammatory processes of ischemic stroke.We found that,during ischemic stroke,T cells and microglia demonstrate a more pronounced synergistic effect.Th1,Th17,and M1 microglia can co-secrete proinflammatory factors,such as interferon-γ,tumor necrosis factor-α,and interleukin-1β,to promote neuroinflammation and exacerbate brain injury.Th2,Treg,and M2 microglia jointly secrete anti-inflammatory factors,such as interleukin-4,interleukin-10,and transforming growth factor-β,to inhibit the progression of neuroinflammation,as well as growth factors such as brain-derived neurotrophic factor to promote nerve regeneration and repair brain injury.Immune interactions between microglia and T cells influence the direction of the subsequent neuroinflammation,which in turn determines the prognosis of ischemic stroke patients.Clinical trials have been conducted on the ways to modulate the interactions between T cells and microglia toward anti-inflammatory communication using the immunosuppressant fingolimod or overdosing with Treg cells to promote neural tissue repair and reduce the damage caused by ischemic stroke.However,such studies have been relatively infrequent,and clinical experience is still insufficient.In summary,in ischemic stroke,T cell subsets and activated microglia act synergistically to regulate inflammatory progression,mainly by secreting inflammatory factors.In the future,a key research direction for ischemic stroke treatment could be rooted in the enhancement of anti-inflammatory factor secretion by promoting the generation of Th2 and Treg cells,along with the activation of M2-type microglia.These approaches may alleviate neuroinflammation and facilitate the repair of neural tissues. 展开更多
关键词 BRAIN IMMUNE INFLAMMATION interaction ischemic stroke mechanism MICROGLIA NEURON secondary injury T cells
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Prognostic model for esophagogastric variceal rebleeding after endoscopic treatment in liver cirrhosis: A Chinese multicenter study 被引量:2
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作者 Jun-Yi Zhan Jie Chen +7 位作者 Jin-Zhong Yu Fei-Peng Xu Fei-Fei Xing De-Xin Wang Ming-Yan Yang Feng Xing Jian Wang Yong-Ping Mu 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期85-101,共17页
BACKGROUND Rebleeding after recovery from esophagogastric variceal bleeding(EGVB)is a severe complication that is associated with high rates of both incidence and mortality.Despite its clinical importance,recognized p... BACKGROUND Rebleeding after recovery from esophagogastric variceal bleeding(EGVB)is a severe complication that is associated with high rates of both incidence and mortality.Despite its clinical importance,recognized prognostic models that can effectively predict esophagogastric variceal rebleeding in patients with liver cirrhosis are lacking.AIM To construct and externally validate a reliable prognostic model for predicting the occurrence of esophagogastric variceal rebleeding.METHODS This study included 477 EGVB patients across 2 cohorts:The derivation cohort(n=322)and the validation cohort(n=155).The primary outcome was rebleeding events within 1 year.The least absolute shrinkage and selection operator was applied for predictor selection,and multivariate Cox regression analysis was used to construct the prognostic model.Internal validation was performed with bootstrap resampling.We assessed the discrimination,calibration and accuracy of the model,and performed patient risk stratification.RESULTS Six predictors,including albumin and aspartate aminotransferase concentrations,white blood cell count,and the presence of ascites,portal vein thrombosis,and bleeding signs,were selected for the rebleeding event prediction following endoscopic treatment(REPET)model.In predicting rebleeding within 1 year,the REPET model ex-hibited a concordance index of 0.775 and a Brier score of 0.143 in the derivation cohort,alongside 0.862 and 0.127 in the validation cohort.Furthermore,the REPET model revealed a significant difference in rebleeding rates(P<0.01)between low-risk patients and intermediate-to high-risk patients in both cohorts.CONCLUSION We constructed and validated a new prognostic model for variceal rebleeding with excellent predictive per-formance,which will improve the clinical management of rebleeding in EGVB patients. 展开更多
关键词 Esophagogastric variceal bleeding Variceal rebleeding Liver cirrhosis Prognostic model Risk stratification Secondary prophylaxis
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Role of triggering receptor expressed on myeloid cells 1/2 in secondary injury after cerebral hemorrhage 被引量:1
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作者 Fan Yi Hao Wu Hai-Kang Zhao 《World Journal of Clinical Cases》 SCIE 2025年第9期1-12,共12页
Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially... Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially among patients with poor functional outcomes.ICH is often accompanied by decreased consciousness and limb dysfunction.This seriously affects patients’ability to live independently.Although rapid advances in neurosurgery have greatly improved patient survival,there remains insufficient evidence that surgical treatment significantly improves long-term outcomes.With in-depth pathophysiological studies after ICH,increasing evidence has shown that secondary injury after ICH is related to long-term prognosis and that the key to secondary injury is various immune-mediated neuroinflammatory reactions after ICH.In basic and clinical studies of various systemic inflammatory diseases,triggering receptor expressed on myeloid cells 1/2(TREM-1/2),and the TREM receptor family is closely related to the inflammatory response.Various inflammatory diseases can be upregulated and downregulated through receptor intervention.How the TREM receptor functions after ICH,the types of results from intervention,and whether the outcomes can improve secondary brain injury and the long-term prognosis of patients are unknown.An analysis of relevant research results from basic and clinical trials revealed that the inhibition of TREM-1 and the activation of TREM-2 can alleviate the neuroinflammatory immune response,significantly improve the long-term prognosis of neurological function in patients with cerebral hemorrhage,and thus improve the ability of patients to live independently. 展开更多
关键词 Cerebral hemorrhage Secondary injury Triggering receptor expressed on myeloid cells 1/2 NEUROSURGERY Inflammatory response
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Recycling technologies of spent lithium-ion batteries and future directions:A review 被引量:4
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作者 Xue-song GAO Meng WU +5 位作者 Guang-jin ZHAO Kun-hong GU Jia-jia WU Hong-bo ZENG Wen-qing QIN Jun-wei HAN 《Transactions of Nonferrous Metals Society of China》 2025年第1期271-295,共25页
Lithium-ion batteries(LIBs)are the most popular energy storage devices due to their high energy density,high operating voltage,and long cycle life.However,green and effective recycling methods are needed because LIBs ... Lithium-ion batteries(LIBs)are the most popular energy storage devices due to their high energy density,high operating voltage,and long cycle life.However,green and effective recycling methods are needed because LIBs contain heavy metals such as Co,Ni,and Mn and organic compounds inside,which seriously threaten human health and the environment.In this work,we review the current status of spent LIB recycling,discuss the traditional pyrometallurgical and hydrometallurgical recovery processes,and summarize the existing short-process recovery technologies such as salt-assisted roasting,flotation processes,and direct recycling.Finally,we analyze the problems and potential research prospects of the current recycling process,and point out that the multidisciplinary integration of recycling will become the mainstream technology for the development of spent LIBs. 展开更多
关键词 spent lithium battery short-process recycling secondary resources PRETREATMENT metal recovery
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Size of the ulna and taxonomic order affect vane dimensions of secondary remiges in birds 被引量:1
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作者 D.C.Deeming E.P.Bayliss E.Ketley 《Avian Research》 2025年第2期284-290,共7页
The number of secondary feathers varies among orders of birds with some orders exhibiting a positive relationship with ulna length,whereas in other orders secondary number is invariant.This difference has implications... The number of secondary feathers varies among orders of birds with some orders exhibiting a positive relationship with ulna length,whereas in other orders secondary number is invariant.This difference has implications for scaling of the width of the feather vane within orders.In those species where the number of secondary remiges is invariant with ulna length,vane width should scale isometrically with ulna size to maintain an aerodynamic flight surface.Where feather count increases with increasing ulna length then vane width should exhibit negative allometry.Vane length should also correlate with ulna length,irrespective of the number of feathers.Data were compiled from an online library of images for the vane length and the width of the vane at 50%of the vane length for the fifth secondary feather for 209 bird species from 24 different orders.The results supported the hypotheses that vane width is a function of ulna size,and the number of secondary feathers as associated with different orders.Vane length was unaffected by the number of secondaries but varied between orders.The results suggest that birds have solved the problem of maintaining the aerodynamic surface of the proximal wing in two ways.Hence as ulna length increases the first solution involves more feathers that exhibit negative allometry for vane width,or in the second where feather count doesn't change,the vane width simply scales isometrically.The implications for the mechanical properties of the vane,and how it affects wing function,have not yet been explored in a range of birds. 展开更多
关键词 AVIAN FEATHER Secondary remiges Ulna length Vane length Vane width
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Creep constitutive model for damaged soft rock based on fractional-order nonlinear theory 被引量:1
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作者 BAO Min ZHOU Zihan +1 位作者 CHEN Zhonghui ZHANG Lingfei 《Journal of Mountain Science》 2025年第6期2276-2290,共15页
Investigating the combined effects of mining damage and creep damage on slope stability is crucial,as it can comprehensively reveal the non-linear deformation characteristics of rock under their joint influence.This s... Investigating the combined effects of mining damage and creep damage on slope stability is crucial,as it can comprehensively reveal the non-linear deformation characteristics of rock under their joint influence.This study develops a fractional-order nonlinear creep constitutive model that incorporates the double damage effect and implements a non-linear creep subroutine for soft rock using the threedimensional finite difference method on the FLAC3D platform.Comparative analysis of the theoretical,numerical,and experimental results reveals that the fractional-order constitutive model,which incorporates the double damage effect,accurately reflects the distinct deformation stages of green mudstone during creep failure and effectively captures the non-linear deformation in the accelerated creep phase.The numerical results show a fitting accuracy exceeding 97%with the creep test curves,significantly outperforming the 61%accuracy of traditional creep models. 展开更多
关键词 Mining damage Creep damage FRACTIONAL-ORDER Constitutive model Secondary development
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Lonicerae flos and turmeric extracts alleviate necrotic enteritis in broilers by modulating gut-liver health and microbiota 被引量:1
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作者 Xingbo Liu Yunru Ji +4 位作者 Huiyuan Lv Zhong Wang Zengpeng Lv Yuming Guo Wei Nie 《Journal of Animal Science and Biotechnology》 2025年第6期2820-2838,共19页
Background Necrotic enteritis(NE)can cause intestinal barrier dysfunction in broilers,leading to secondary liver injury(SLI).In this process,the gut-liver axis plays a crucial role.Lonicerae flos and turmeric extracts... Background Necrotic enteritis(NE)can cause intestinal barrier dysfunction in broilers,leading to secondary liver injury(SLI).In this process,the gut-liver axis plays a crucial role.Lonicerae flos and turmeric extracts(LTE),containing chlorogenic acid and curcumin,have been reported to possess anti-inflammatory,and antioxidant properties.Based on these potential biological benefits,this study aims to investigate the reparative effects of LTE on the intestinal barrier dysfunction in NE-infected broilers and assess its therapeutic efficacy in alleviating SLI.By elucidating the regulatory mechanisms of LTE on gut-liver axis health,this research provides new insights into the prevention and treatment of NE in broilers.Results LTE improved body weight and average daily gain while reducing intestinal lesion scores,coccidia oocysts,and Clostridium perfringens counts in NE broilers(P<0.05).LTE enhanced intestinal morphology and up-regulated the expression of tight junction protein genes(CLDN1,TJP1)and MUC2,suppressed pro-inflammatory cytokine and myeloperoxidase(MPO)levels,and minimized endotoxin(ET)accumulation in NE broilers(P<0.05).Furthermore,LTE alleviated oxidative stress in ileal cells and protected mitochondrial structure and function in NE broilers.NE infection induced intestinal permeability in broilers,leading to increased serum pro-inflammatory cytokines and intestinal-derived endotoxin levels,which caused liver damage.LTE significantly reduced liver pathologic damage,pro-inflammatory cytokine levels,aspartate transaminase,alanine aminotransferase,and ROS levels in NE broilers(P<0.05).Additionally,16S rRNA sequencing revealed that NE significantly increased the relative abundance of Barnesiella and decreased the relative abundance of Bacteroidota,Desulfobacterota and Bacteroides in the cecum of broilers.LTE enhanced intestinal microbiota diversity and reduced the segregation of intestinal microbiota induced by NE infection.Conclusions In summary,LTE can alleviate NE and SLI by modulating the microbiota,inhibiting inflammation and oxidative stress,and ameliorating mitochondrial dysfunction,thereby enhancing gut-liver axis health and growth performance. 展开更多
关键词 Chlorogenic acid CURCUMIN MICROBIOTA Mitochondrial dysfunction Necrotic enteritis Secondary liver injury
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Recent progress of Prussian blue analogues as cathode materials for metal ion secondary batteries 被引量:1
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作者 Xin-Yuan Fu Lu-Lu Zhang +2 位作者 Cheng-Cheng Wang Hua-Bin Sun Xue-Lin Yang 《Rare Metals》 2025年第1期34-59,共26页
With the rapid development of new energy and the high proportion of new energy connected to the grid,energy storage has become the leading technology driving significant adjustments in the global energy landscape.Elec... With the rapid development of new energy and the high proportion of new energy connected to the grid,energy storage has become the leading technology driving significant adjustments in the global energy landscape.Electrochemical energy storage,as the most popular and promising energy storage method,has received extensive attention.Currently,the most widely used energy storage method is metal-ion secondary batteries,whose performance mainly depends on the cathode material.Prussian blue analogues(PBAs)have a unique open framework structures that allow quick and reversible insertion/extraction of metal ions such as Na^(+),K^(+),Zn^(2+),Li^(+)etc.,thus attracting widespread attention.The advantages of simple synthesis process,abundant resources,and low cost also distinguish it from its counterparts.Unfortunately,the crystal water and structural defects in the PBAs lattice that is generated during the synthesis process,as well as the low Na content,significantly affect their electrochemical performance.This paper focuses on PBAs’synthesis methods,crystal structure,modification strategies,and their potential applications as cathode materials for various metal ion secondary batteries and looks forward to their future development direction. 展开更多
关键词 Prussian blue analogs Cathode material Metal-ion secondary batteries Synthesis method Modification strategy
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Characteristics of Massive Glacier-Related Watershed Geohazard Chains in the Eastern Himalayan Syntaxis,China 被引量:1
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作者 Shaohua Gao Yang Gao +4 位作者 Yueping Yin Bin Li Wenpei Wang Tiantian Zhang Haoyuan Gao 《Journal of Earth Science》 2025年第3期1181-1197,共17页
Frequent glacier-related watershed geohazard chains are causing severe damage to life and infrastructure,reported consistently from the Eastern Himalayan Syntaxis.This paper presents a systematic method for researchin... Frequent glacier-related watershed geohazard chains are causing severe damage to life and infrastructure,reported consistently from the Eastern Himalayan Syntaxis.This paper presents a systematic method for researching geohazard,from regional to individual scale.The methodology includes the establishment of geological chain inventories,discrimination of geohazard chain modes,analyses of dynamics and dam breaches,and risk assessments.The following results were obtained:(1)In the downstream of Yarlung Zangbo River,175 sites were identified as high-risk for river blockage disasters,indicating the development of watershed geohazards.Five geohazard chain modes were summarized by incorporating geomorphological characteristics,historical events,landslide zoning,and materials.The risk areas of typical hazard were identified and assessed using InSAR data.(2)Glacier-related watershed geohazard chains are significantly different from traditional landslides.A detailed inversion analysis was conducted on the massive rock-ice avalanche in the Sedongpu gully in 2021.This particular event lasted roughly 300 seconds,with a maximum flow velocity of 77.2 m/s and a maximum flow height of 93 meters.By scrutinizing the dynamic processes and mechanical characteristics,mobility stages and phase transitions can be divided into four stages.(3)Watershed geohazard chains tend to block rivers.The peak breach discharge of the Yigong Landslide reached 12.4×10^(4) m^(3)/s,which is 36 times the volume of the seasonal flood discharge in the Yigong River.Megafloods caused by landslide dam breaches have significantly shaped the geomorphology.This study offers insights into disaster patterns and the multistaged movement characteristics of glacier-related watershed geohazard chains,providing a comprehensive method for investigations and assessments in glacial regions. 展开更多
关键词 glacier-related watershed geohazard chains geohazard chain modes secondary hazards InSAR Eastern Himalayan Syntax DISASTERS glaciers
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Improving microstructure,tensile properties and corrosion resistance of AA6016 and AA2519 alloys friction stir lap joints via TIG arc 被引量:1
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作者 Tie YI Sheng-dan LIU +2 位作者 Chen FANG Geng-duo JIANG Xuan-xuan DAI 《Transactions of Nonferrous Metals Society of China》 2025年第2期405-417,共13页
The effects of tungsten inert gas arc-assisted friction stir welding(TIG-FSW)on the microstructure,tensile properties and corrosion resistance of AA6016 and AA2519 alloys lap joints were investigated by means of optic... The effects of tungsten inert gas arc-assisted friction stir welding(TIG-FSW)on the microstructure,tensile properties and corrosion resistance of AA6016 and AA2519 alloys lap joints were investigated by means of optical microscope,scanning electron microscope,tensile test at room temperature,corrosion immersion tests and electrochemical measurements.The results show that the introduction of TIG arc during FSW process results in a more uniform microstructure of the joint with no tunnel hole defects.Furthermore,it enhances tensile strength and elongation of the joint with increased rates of 11.5%and 50.0%,respectively;meanwhile,the corrosion current density and largest corrosion depth are decreased with reduction rates of 78.2%and 45.7%,respectively.TIG-FSW can promote flow,contact and diffusion of materials,thus improving microstructure of the joint.Additionally,it reduces the size and number of secondary phase particles.Consequently,these factors contribute to the higher tensile properties and corrosion resistance of the joints. 展开更多
关键词 friction stir welding lap joint dissimilar aluminum alloys secondary phase particles MICROSTRUCTURE tensile properties corrosion resistance
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Tree growth and mortality of secondary evergreen broadleaved and temperate coniferous forests and their drivers along elevation gradients in subtropical mountain of China 被引量:1
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作者 Zongren Li Wenjun Lin +3 位作者 Zhijie Guan Jinlin Zhang Shipin Chen Weibin You 《Journal of Forestry Research》 2025年第2期137-148,共12页
Over the past decades,the expansion of natu-ral secondary forests has played a crucial role in offsetting the loss of primary forests and combating climate change.Despite this,there is a gap in our understanding of ho... Over the past decades,the expansion of natu-ral secondary forests has played a crucial role in offsetting the loss of primary forests and combating climate change.Despite this,there is a gap in our understanding of how tree species’growth and mortality patterns vary with eleva-tion in these secondary forests.In this study,we analyzed data from two censuses(spanning a five-year interval)conducted in both evergreen broadleaved forests(EBF)and temperate coniferous forests(TCF),which have been recovering for half a century,across elevation gradients in a subtropical mountain region,Mount Wuyi,China.The results indicated that the relative growth rate(RGR)of EBF(0.028±0.001 cm·cm^(-1)·a^(-1))and the mortality rate(MR)(20.03%±1.70%)were 27.3%and 16.4%higher,respec-tively,than those of TCF.Interestingly,the trade-off between RGR and MR in EBF weakened as elevation increased,a trend not observed in TCF.Conversely,TCF consistently showed a stronger trade-off between RGR and MR compared to EBF.Generalized linear mixed models revealed that ele-vation influences RGR both directly and indirectly through its interactions with slope,crown competition index(CCI),and tree canopy height(CH).However,tree mortality did not show a significant correlation with elevation.Additionally,DBH significantly influenced both tree growth and mortal-ity,whereas and CH and CCI had opposite effects on tree growth between EBF and TCF.Our study underscores the importance of elevation in shaping the population dynamics and the biomass carbon sink balance of mountain forests.These insights enhance our understanding of tree species’life strategies,enabling more accurate predictions of forest dynamics and their response to environmental changes. 展开更多
关键词 Trade-offs Generalized linear mixed models(GLMM) Remote sensing Secondary forest Mount Wuyi
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