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Integrated biomarker response to assess toxic impacts of iron and manganese on deep-sea mussel Gigantidas platifrons under a deep-sea mining activity scenario
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作者 Li ZHOU Mengna LI +7 位作者 Zhaoshan ZHONG Minxiao WANG Hao CHEN Chao LIAN Hao WANG Huan ZHANG lei cao Chaolun LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期522-532,共11页
Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient... Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient knowledge about the impact of metal exposure on its inhabitants.In this study,deep-sea mussel Gigantidas platifrons,a commonly used deep-sea toxicology model organism,was exposed to manganese(100,1000μg/L)or iron(500,5000μg/L)for 7 d,respectively.Manganese and iron were chosen for their high levels of occurrence within deep-sea deposits.Metal accumulation and a battery of biochemical biomarkers related to antioxidative stress in superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA);immune function in alkaline phosphatase(AKP),acid phosphatase(ACP);and energy metabolism in pyruvate kinase(PK)and hexokinase(HK)were assessed in mussel gills.Results showed that deep-sea mussel G.platifrons exhibited a high capacity to accumulate Mn/Fe.In addition,most tested biochemical parameters were altered by metal exposure,demonstrating that metals could induce oxidative stress,suppress the immune system,and affect energy metabolism of deep-sea mussels.The integrated biomarker response(IBR)approach indicated that the exposure to Mn/Fe had a negative impact on deep-sea mussels,and Mn demonstrated a more harmful impact on deep-sea mussels than Fe.Additionally,SOD and CAT biomarkers had the greatest impact on IBR values in Mn treatments,while ACP and HK were most influential for the low-and high-dose Fe groups,respectively.This study represents the first application of the IBR approach to evaluate the toxicity of metals on deep-sea fauna and serves as a crucial framework for risk assessment of deep-sea mining-associated metal exposure. 展开更多
关键词 MUSSEL metal deep-sea mining BIOMARKER environmental monitoring
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Advances in non-invasive imaging of proteinopathies in animal models of neurodegenerative diseases
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作者 lei cao Bin Ji Ruiqing Ni 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2115-2116,共2页
Neurodegenerative diseases,including Alzheimer's disease(AD),frontotemporal dementia,Parkinson's disease,and dementia with Lewy bodies,represent tremendous unmet clinical needs.A common feature of these diseas... Neurodegenerative diseases,including Alzheimer's disease(AD),frontotemporal dementia,Parkinson's disease,and dementia with Lewy bodies,represent tremendous unmet clinical needs.A common feature of these diseases is the aberrant cerebral accumulation of pathological protein aggregates,affecting selectively vulnerable circuits in a disease-specific pattern.Earlier studies have established a relationship between abnormal aggregation and neuronal dysfunction or loss,suggesting multifactorial pathogenesis mechanisms in these neurodegenerative disorders. 展开更多
关键词 DISEASES DEGENERATIVE CLINICAL
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Treatment of hemolymphangioma by robotic surgery: A case report
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作者 Tian-Ning Li Yan-Hong Liu +2 位作者 Jia Zhao Hong Mu lei cao 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期596-600,共5页
BACKGROUND Hemolymphangioma of the jejunum is rare and lacks clinical specificity,and can manifest as gastrointestinal bleeding,abdominal pain,and intestinal obstruction.Computed tomography,magnetic resonance imaging,... BACKGROUND Hemolymphangioma of the jejunum is rare and lacks clinical specificity,and can manifest as gastrointestinal bleeding,abdominal pain,and intestinal obstruction.Computed tomography,magnetic resonance imaging,and other examinations show certain characteristics of the disease,but lack accuracy.Although capsule endoscopy and enteroscopy make up for this deficiency,the diagnosis also still re-quires pathology.CASE SUMMARY A male patient was admitted to the hospital due to abdominal distension and abdominal pain,but a specific diagnosis by computed tomography examination was not obtained.Partial resection of the small intestine was performed by robotic surgery,and postoperative pathological biopsy confirmed the diagnosis of hemo-lymphangioma.No recurrence in the follow-up examination was observed.CONCLUSION Robotic surgery is an effective way to treat hemolymphangioma through minima-lly invasive techniques under the concept of rapid rehabilitation. 展开更多
关键词 Hemolymphangioma ENTEROSCOPY Robotic surgery REHABILITATION Case report
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Incidence and Risk Factors of Sub-syndromal Delirium in Patients after Cardiac Surgery
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作者 Baoyi YANG Longti LI +3 位作者 Na WANG Yan ZHAN lei cao Rong WANG 《Medicinal Plant》 2024年第1期62-65,78,共5页
[Objectives]This study aimed to investigate the incidence and risk factors associated with SSD in patients following cardiac surgery.[Methods]A total of 378 patients who underwent cardiac surgery in Taihe Hospital wer... [Objectives]This study aimed to investigate the incidence and risk factors associated with SSD in patients following cardiac surgery.[Methods]A total of 378 patients who underwent cardiac surgery in Taihe Hospital were recruited and screened.Diagnosis of delirium was made using evaluation methods and DSM-5 criteria.SSD was defined as the presence of one or more core features of delirium without meeting the full diagnostic criteria.Statistical analysis included independent samples t-test for group comparisons and binary logistic regression analysis to identify independent risk factors for SSD after cardiac surgery.[Results]Among the 378 subjects,112(29.63%)had SSD,28(7.41%)had delirium,and the remaining 238 patients(62.96%)did not present with delirium.Univariate analysis revealed that age,APACHE II score,duration of aortic clamping,length of ICU stay,duration of sedation use,and daily sleep time were significant risk factors for the occurrence of SSD(P<0.05).Logistic regression analysis identified age>70 years old,APACHE II score>20 points,length of ICU stay>5 d,and duration of sedation use>24 h as independent risk factors for SSD after cardiac surgery(P<0.05).A functional model was fitted based on the analysis results of the binary logistic regression model,yielding the equation logit P=1.472X_(1)+2.213X_(2)+3.028X_(3)+1.306X_(4).[Conclusions]Comprehensive clinical assessment is crucial for patients undergoing cardiac surgery,and appropriate preventive measures should be taken for patients with identified risk factors.Close monitoring of the patient s consciousness should be implemented postoperatively,and timely interventions should be conducted.Further research should focus on model validation and optimization. 展开更多
关键词 Subsyndromal delirium Cardiac surgery PATIENT Confusion assessment method for intensive care units version(CAM-ICU)
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Maternal organic selenium supplementation during gestation enhances muscle fiber area and muscle fiber maturation of offspring in porcine model
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作者 Yan Lin Hui Yan +14 位作者 lei cao Daolin Mou Dajiang Ding Binting Qin Lianqiang Che Zhengfeng Fang Shengyu Xu Yong Zhuo Jian Li Jianping Wang Chao Huang Yuanfeng Zou Lixia Li De Wu Bin Feng 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第2期654-665,共12页
Background:Organic selenium supplementation during gestation improves the antioxidant status and reproduc-tive performance of sows and increases the antioxidative capacity of the intestines of their offspring.This stu... Background:Organic selenium supplementation during gestation improves the antioxidant status and reproduc-tive performance of sows and increases the antioxidative capacity of the intestines of their offspring.This study was conducted to investigate the effect of maternal basel diet(control)supplemented with an organic Se,2-hydroxy-4-methylselenobutanoic acid(HMSeBA),or inorganic sodium selenite(Na_(2)SeO_(3))during gestation on the antioxidant status and development of muscle in newborn and weaned piglets.Newborn piglets before colostrum intake and weaned piglets were selected for longissimus dorsi(LD)muscle collection and analysis.Results:The results showed that maternal HMSeBA supplementation increased the muscle area and content of Se in the LD muscle of newborn piglets,improved gene expression of selenoproteins,and decreased oxidative status in the LD muscle of both newborn and weaned piglets compared with the control.The expression of muscle development-related genes of newborn piglets in the HMSeBA group was lower than in the control group,whereas the expression of MRF4 in weaned piglets was higher in the HMSeBA group than in the control and Na_(2)SeO_(3)groups.In addition,HMSeBA supplementation decreased the mRNA expressions of myosin heavy chains(MyHC)IIx and MyHC IIb and the percentage of MyHC IIb;increased the expression of PGC-1αin the LD muscle of newborn piglets;increased the gene expression of MyHC IIa;and decreased the protein expression of slow MyHC and the activity of malate dehydrogenase in the LD muscle of weaned piglets compared with the control group.Conclusions:Maternal HMSeBA supplementation during gestation can improve the antioxidative capacity of the muscle of their offspring and promote the maturity of muscle fibres in weaned offspring. 展开更多
关键词 ANTIOXIDATION HMSeBA Muscle OFFSPRING SOWS
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Metronomic capecitabine inhibits liver transplant rejection in rats by triggering recipients’T cell ferroptosis
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作者 Hao Wang Zheng-Lu Wang +12 位作者 Sai Zhang De-Jun Kong Rui-Ning Yang lei cao Jian-Xi Wang Sei Yoshida Zhuo-Lun Song Tao Liu Shun-Li Fan Jia-Shu Ren Jiang-Hong Li Zhong-Yang Shen Hong Zheng 《World Journal of Gastroenterology》 SCIE CAS 2023年第20期3084-3102,共19页
BACKGROUND Capecitabine(CAP)is a classic antimetabolic drug and has shown potential antirejection effects after liver transplantation(LT)in clinical studies.Our previous study showed that metronomic CAP can cause the ... BACKGROUND Capecitabine(CAP)is a classic antimetabolic drug and has shown potential antirejection effects after liver transplantation(LT)in clinical studies.Our previous study showed that metronomic CAP can cause the programmed death of T cells by inducing oxidative stress in healthy mice.Ferroptosis,a newly defined non-apoptotic cell death that occurs in response to iron overload and lethal levels of lipid peroxidation,is an important mechanism by which CAP induces cell death.Therefore,ferroptosis may also play an important role in CAP-induced T cell death and play an immunosuppressive role in acute rejection after transplantation.AIM To investigate the functions and underlying mechanisms of antirejection effects of metronomic CAP.METHODS A rat LT model of acute rejection was established,and the effect of metronomic CAP on splenic hematopoietic function and acute graft rejection was evaluated 7 d after LT.In vitro,primary CD3+T cells were sorted from rat spleens and human peripheral blood,and co-cultured with or without 5-fluorouracil(5-FU)(active agent of CAP).The levels of ferroptosis-related proteins,ferrous ion concentration,and oxidative stress-related indicators were observed.The changes in mitochondrial structure were observed using electron microscopy.RESULTS With no significant myelotoxicity,metronomic CAP alleviated graft injury(Banff score 9 vs 7.333,P<0.001),prolonged the survival time of the recipient rats(11.5 d vs 16 d,P<0.01),and reduced the infiltration rate of CD3+T cells in peripheral blood(6.859 vs 3.735,P<0.001),liver graft(7.459 vs 3.432,P<0.001),and spleen(26.92 vs 12.9,P<0.001),thereby inhibiting acute rejection after LT.In vitro,5-FU,an end product of CAP metabolism,induced the degradation of the ferritin heavy chain by upregulating nuclear receptor coactivator 4,which caused the accumulation of ferrous ions.It also inhibited nuclear erythroid 2 p45-related factor 2,heme oxygenase-1,and glutathione peroxidase 4,eventually leading to oxidative damage and ferroptosis of T cells.CONCLUSION Metronomic CAP can suppress acute allograft rejection in rats by triggering CD3+T cell ferroptosis,which makes it an effective immunosuppressive agent after LT. 展开更多
关键词 CAPECITABINE Ferroptosis T Lymphocytes Immunosuppressive agents Graft rejection Liver transplantation
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Robust Watermarking Algorithm for Medical Volume Data Based on Polar Cosine Transform and 3D-DCT
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作者 Pengju Zhang Jingbing Li +4 位作者 Uzair Aslam Bhatti Jing Liu Yen-wei Chen Dekai Li lei cao 《Computers, Materials & Continua》 SCIE EI 2023年第6期5853-5870,共18页
The amount of 3D data stored and transmitted in the Internet of Medical Things(IoMT)is increasing,making protecting these medical data increasingly prominent.However,there are relatively few researches on 3D data wate... The amount of 3D data stored and transmitted in the Internet of Medical Things(IoMT)is increasing,making protecting these medical data increasingly prominent.However,there are relatively few researches on 3D data watermarking.Moreover,due to the particularity of medical data,strict data quality should be considered while protecting data security.To solve the problem,in the field of medical volume data,we proposed a robust watermarking algorithm based on Polar Cosine Transform and 3D-Discrete Cosine Transform(PCT and 3D-DCT).Each slice of the volume data was transformed by PCT to obtain feature row vector,and then the reshaped three-dimensional feature matrix was transformed by 3D-DCT.Based on the contour information of the volume data and the detail information of the inner slice,the visual feature vector was obtained by applying the per-ceptual hash.In addition,the watermark was encrypted by a multi-sensitive initial value Sine and Piecewise linear chaotic Mapping(SPM)system,and embedded as a zero watermark.The key was stored in a third party.Under the same experimental conditions,when the volume data is rotated by 80 degrees,cut 25%along the Z axis,and the JPEG compression quality is 1%,the Normalized Correlation Coefficient(NC)of the extracted watermark is 0.80,0.89,and 1.00 respectively,which are significantly higher than the comparison algorithm. 展开更多
关键词 Volume data watermark zero watermark SPM PCT and 3D-DCT
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Cu-SAPO-34催化剂的低温水热稳定性及其对NH_3选择催化还原NO_x反应性能的影响(英文) 被引量:10
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作者 向骁 吴鹏飞 +5 位作者 曹毅 曹磊 王全义 徐舒涛 田鹏 刘中民 《Chinese Journal of Catalysis》 EI CSCD 北大核心 2017年第5期918-927,共10页
随着柴油车数量的增加,NO_x污染的控制成为了当今社会的一个重要议题,NO_x可以导致酸雨,光化学烟雾以及慢性健康问题.目前,具有八元环孔口的含铜CHA型分子筛(包括Cu-SSZ-13和Cu-SPAO-34)具有优异的高温水热稳定性及宽温度范围内的活性和... 随着柴油车数量的增加,NO_x污染的控制成为了当今社会的一个重要议题,NO_x可以导致酸雨,光化学烟雾以及慢性健康问题.目前,具有八元环孔口的含铜CHA型分子筛(包括Cu-SSZ-13和Cu-SPAO-34)具有优异的高温水热稳定性及宽温度范围内的活性和N_2选择性,是最具有吸引力的氨选择催化还原催化剂,而且在欧洲和美国已经得到了应用.SAPO-34分子筛的一个重要缺陷就是在100 ℃以下,对水较为敏感,这主要是由于Si–O–Al键的水解造成的.研究表明,在室温下接触水蒸气后,SAPO-34的结晶度和比表面积只能部分恢复,而如果长达数月甚至更长时间的接触后,分子筛将会遭受骨架坍塌等不可逆的破坏,到目前为止,Cu-SAPO-34的低温水热稳定性相关问题并未得到清楚的阐述.本文系统研究了不同铜含量和硅含量的Cu-SAPO-34催化剂的低温水热稳定性.结果显示,低温水热处理后,所有催化剂的NH_3氧化活性和NH_3-SCR活性(主要是低温活性)都有所下降.29Si MAS NMR结果表明,在低温水热处理过程中,骨架结构的破坏在所难免,但催化剂上铜含量的增加有助于Cu-SAPO-34的骨架结构和酸性的更好保持.EPR结果表明,当催化剂上铜含量较低时,孤立Cu^(2+)的稳定性和SAPO分子筛骨架的稳定性呈现正相关的关系.具有较高铜含量(如3.67 wt%)的样品,尽管其骨架结构和酸性在低温水热处理过程中可以得到较好的保持,但活性Cu^(2+)的量仍会有明显的下降.由于部分样品在低温水处理后,NH_3氧化反应活性下降,我们推测CuO颗粒发生了聚结,从而抑制了催化剂的NH_3氧化反应活性,N_2O化学吸附实验也证实了该结论.在所有催化剂中,具有中等铜含量(1.37%)的高硅Cu-SAPO-34样品在低温水处理过程中的Cu^(2+)量和酸性质均得到了较好的保持,所以其水处理后的NH_3-SCR活性衰减最小. 展开更多
关键词 Cu-SAPO-34 低温水热稳定性 氮氧化物 选择催化还原 氨氧化
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重构法合成Cu-SAPO-34及其NH3-SCR催化性能 被引量:3
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作者 孙丽婧 杨淼 +6 位作者 曹毅 田鹏 吴鹏飞 曹磊 徐舒涛 曾姝 刘中民 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第9期1410-1420,共11页
氨选择催化还原NOx(NH3-SCR)是重要的柴油车尾气脱硝技术.发展高效且稳定的催化剂是提升该技术指标、应对严苛排放标准的关键.近年来,以Cu-SSZ-13和Cu-SAPO-34为代表的金属离子负载分子筛催化剂材料因其较宽的活性温度窗口和高水热稳定... 氨选择催化还原NOx(NH3-SCR)是重要的柴油车尾气脱硝技术.发展高效且稳定的催化剂是提升该技术指标、应对严苛排放标准的关键.近年来,以Cu-SSZ-13和Cu-SAPO-34为代表的金属离子负载分子筛催化剂材料因其较宽的活性温度窗口和高水热稳定性受到研究者的广泛关注.Cu-SSZ-13分子筛催化剂已被BASF公司商业应用.相较Cu-SSZ-13,Cu-SAPO-34具有更优的低温活性与高温水热稳定性,且合成成本低廉.但Cu-SAPO-34的低温耐水性差,当采用传统的金属离子负载过程进行反复多次离子交换时,存在分子筛结晶度下降(部分骨架结构塌陷)的风险.使用铜四乙烯五胺络合物(Cu-TEPA)作为模板剂和铜源一步合成Cu-SAPO-34可以避免反复的离子交换过程,但由于Cu-TEPA的模板导向能力过强,Cu负载量难以控制,而降低Cu-TEPA的投料量则会损失产品收率.同时,该方法合成的Cu-SAPO-34中含有大量硅岛,分子筛催化剂的水热稳定性显著降低.针对这些问题,本文提出利用一步合成的高铜含量Cu-SAPO-34作为前驱体与铜源合成Cu-SAPO-34的方法(命名为重构法).该方法不仅产品收率高,而且Cu和Si的含量/分布可控,合成样品的NH3-SCR催化性能和水热稳定性也明显提升.EDX结果显示,焙烧后的Cu-SAPO-34中铜分布均匀,说明前驱体充分参与了Cu-SAPO-34的重构.13C NMR和元素分析结果显示,相较一步法合成的Cu-SAPO-34,重构的Cu-SAPO-34中的四乙烯五胺在模板剂中的比例明显下降.Cu-TEPA限域在前驱体的CHA笼中,有效抑制其结构导向剂的作用.Cu引入量由前驱体加入量决定.29Si NMR结果显示,Cu-SAPO-34中的硅主要呈Si(4Al)分布,这有利于Cu-SAPO-34保持良好的高温水热稳定性.NH3-SCR反应结果显示,相较一步法合成的Cu-SAPO-34,重构的Cu-SAPO-34表现出良好的NH3-SCR反应活性和更优异的高温水热稳定性.不同硅含量的重构Cu-SAPO-34的NH3-SCR反应结果显示:在低温段,低硅含量的Cu-SAPO-34具有更高的反应活性;在高温段,高硅含量的Cu-SAPO-34具有更高的反应活性.通过NH3-TPD和原位红外漫反射分析发现,低硅含量的Cu-SAPO-34具有相对较弱的酸性,使得吸附的氨具有较高的反应性,催化剂的低温活性较高. 展开更多
关键词 Cu-SAPO-34 水热合成 NH3-SCR 水热稳定性 晶化
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Cu-SAPO-17:一种新颖的NOx选择性催化还原催化剂
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作者 刘晓娜 曹毅 +5 位作者 闫娜娜 马超 曹磊 郭鹏 田鹏 刘中民 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第11期1715-1722,共8页
在柴油机排放后处理系统中,颗粒捕捉器经常放在氨气选择性催化还原(NH3-SCR)催化剂附近.在颗粒捕捉器的再生环节中,其需要加热到873 K以上.同时,在柴油机存储和冷启动阶段, NH3-SCR催化剂需要暴露在低温(373 K以下)条件下.因此, NH3-SC... 在柴油机排放后处理系统中,颗粒捕捉器经常放在氨气选择性催化还原(NH3-SCR)催化剂附近.在颗粒捕捉器的再生环节中,其需要加热到873 K以上.同时,在柴油机存储和冷启动阶段, NH3-SCR催化剂需要暴露在低温(373 K以下)条件下.因此, NH3-SCR催化剂需要同时具备优异的高温水热稳定性和低温水热稳定性.在现有NH3-SCR催化剂中,铜交换的磷酸硅铝(SAPO)分子筛由于具有优异的高温水热稳定性而受到广泛关注.到目前为止,在现有41种SAPO分子筛中,仅有Cu-SAPO-34, Cu-SAPO-18, Cu-SAPO-35, Mn Ox-SAPO-11和Cu-SAPOSTA-7被应用到NH3-SCR反应中.在这些SAPO分子筛中,除SAPO-11外,其他分子筛都具有小孔大笼的特征.然而, SAPO分子筛在NH3-SCR反应中的广泛应用一直受到其低温水热稳定性的限制.因此,研究者们一直致力于研发其他具有小孔大笼特征的SAPO分子筛,以实现低温水热稳定性和高温水热稳定性兼备.本文报道了一个新颖的Cu-SAPO-17催化剂的合成,并首次将其应用于NH3-SCR反应中.SAPO-17具有三维8×8×8孔道结构,由沿着c轴的eri笼和can-dσr构成.首先采用廉价的环己胺(CHA)作为模板剂制备SAPO-17原粉,随后对SAPO-17原粉进行铜离子交换和焙烧,得到Cu-SAPO-17催化剂.通过优化催化剂的硅含量和铜含量,我们发现Cu-SAPO-17-8.0%-0.22催化剂表现出优异的低温水热稳定性和高温水热稳定性.该催化剂在353 K和10%H2O的氮气气氛下老化24 h后(低温水热老化),可以保持90%以上的新鲜活性;在973 K和10%H2O的空气气氛下老化16 h后(高温水热老化),在473 K下仍然可以达到50%以上的NO转化率.通过X射线粉末精修(Rietveld精修)SAPO-17-8.0%(未焙烧)确定了模板剂环己胺的落位、分子筛中的主客体相互作用以及Bronsted酸位点分布.精修结果显示:1)一个eri笼子中包含两个质子化的环己胺;2)环己胺上的N原子与骨架上的O4形成了经典的氢键(N–H...O4=2.96A).这意味着催化剂焙烧之后,与氢键相连的O4即是Bronsted酸位点.因为O4与P1相连,所以在忽略硅岛的影响时,可以认为Si在SAPO-17-8.0%中主要取代P1位点.结合EPR结果,我们推测出两种Cu2+的可能落位. 展开更多
关键词 SAPO-17分子筛 RIETVELD精修 主客体相互作用 氨气选择性催化还原(NH3-SCR) 水热稳定性 Cu2+落位
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Spring migration duration exceeds that of autumn migration in Far East Asian Greater White-fronted Geese (Anser albifrons) 被引量:9
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作者 Xueqin Deng Qingshan Zhao +5 位作者 lei Fang Zhenggang Xu Xin Wang Haoren He lei cao Anthony David Fox 《Avian Research》 CSCD 2019年第3期319-329,共11页
Background:Migration theory suggests,and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success,long-distance avian migrants tend to adopt a time minimizati... Background:Migration theory suggests,and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success,long-distance avian migrants tend to adopt a time minimization strategy during spring migration, resulting in shorter duration spring migration compared to that in autumn.Methods:Using GPS/GSM transmitters,we tracked the full migrations of 11 Greater White-fronted Geese (Anser albifrons) between southeast China and the Russian Arctic,to reveal the migration timing and routes of the East Asian population, and compare the difference in duration between spring and autumn migration of this population.Results:We found that migration in spring (79 ± 12 days) took more than twice as long to cover the same distance as in autumn (35 ±7 days).This difference in migration duration was mainly determined by significantly more time spent in spring (59±16 days) than in autumn (23± 6days) at significantly more stopover sites. Conclusions:We suggest that these geese, thought to be partial capital breeders, spent almost three quarters of total migration time at spring stopover sites to acquire energy stores for ultimate investment in reproduction, although we cannot reject the hypothesis that timing of the spring thaw also contributed to stopover duration.In autumn,they acquired necessary energy stores on the breeding grounds sufficient to reach Northeast China staging areas almost without stop, which reduced stopover times in autumn and resulted in the faster autumn migration than spring. 展开更多
关键词 GREATER White-fronted Goose GPS/GSM tracking Migration Spring staging STOPOVER DURATION
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Adjusting the SnZn defects in Cu_(2)ZnSn(S,Se)_(4) absorber layer via Ge^(4+) implanting for efficient kesterite solar cells 被引量:4
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作者 Yueqing Deng Zhengji Zhou +7 位作者 Xin Zhang lei cao Wenhui Zhou Dongxing Kou Yafang Qi Shengjie Yuan Zhi Zheng Sixin Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第10期1-7,I0001,共8页
The development of kesterite photovoltaic solar cells has been hindered by large open-circuit voltage(V_(oc))deficit.Recently,Snzn deep point defect and associative defect cluster have been recognized as the main culp... The development of kesterite photovoltaic solar cells has been hindered by large open-circuit voltage(V_(oc))deficit.Recently,Snzn deep point defect and associative defect cluster have been recognized as the main culprit for the Voc losses.Therefore,manipulating the deep-level donor of Snzn antisite defects is crucial for breaking through the bottleneck of present Cu_(2) ZnSn(S,Se)_(4)(CZTSSe)photovoltaic technology.In this study,the Snzn deep traps in CZTSSe absorber layer are suppressed by incorporation of Ge.The energy levels and concentration of Snzn defects measured by deep-level transient spectroscopy(DLTS)decrease significantly.In addition,the grain growth of CZTSSe films is also promoted due to Ge implantation,yielding the high quality absorber layer.Consequently,the efficiency of CZTSSe solar cells increases from 9.15%to 11.48%,largely attributed to the 41 mV Voc increment. 展开更多
关键词 CZTSSe Defect Absorber layer Solar cells V_(oc)
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Migration routes,population status and important sites used by the globally threatened Black-faced Spoonbill(Platalea minor):a synthesis of surveys and tracking studies 被引量:3
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作者 Yiwen Chen Yat-tung Yu +3 位作者 Fanjuan Meng Xueqin Deng lei cao Anthony David Fox 《Avian Research》 SCIE CSCD 2021年第4期425-441,共17页
Background:The Black-faced Spoonbill(Platalea minor)is a globally threatened species,nesting mainly in western Korea with smaller numbers breeding in Liaoning Province,China,and Far East Russia.Recent winter field sur... Background:The Black-faced Spoonbill(Platalea minor)is a globally threatened species,nesting mainly in western Korea with smaller numbers breeding in Liaoning Province,China,and Far East Russia.Recent winter field surveys to estimate the species'population size were almost totally conducted in coastal areas,but tracking studies showed that some individuals now winter inland.To ensure its long-term survival,we need a more comprehensive assessment of the current distribution and abundance of the species.Methods:We combined the most recent count data and satellite tracking information to update existing informa-tion about the population abundance and distribution of the Black-faced Spoonbill at all stages of its annual life cycle,and how these have changed during 2004-2020.Results:Black-faced Spoonbills mainly breed on the west coast of the Korean peninsula,while immature birds show a wider summer distribution throughout Yellow Sea coastal areas,when a few remain on wintering sites in the south.Combined tracking results and mid-winter counts confirmed known wintering sites on the east and south coasts of China,but showed that the species also winters on wetlands in the Yangtze River floodplain and in Southeast Asia.During 2004-2020,counts of wintering birds in coastal habitats increased from 1198 to 4864,with numbers wintering on the island of Taiwan contributing most to the overall increase.Latest counts found 5222 in 2021.We also identify key wintering and stopover sites as well as their current conservation status.Conclusions:This study revised the known summering and wintering ranges of the Black-faced Spoonbill and assessed the conservation status of key sites based on a combination of field survey and satellite tracking data.We recommend prioritisation of further field research to identify and survey inland wintering areas in the Yangtze River floodplain and summering areas of immature birds.More tracking of adult individuals and birds during spring migration is necessary to fill these information gaps.We also suggest establishing a Black-faced Spoonbill monitoring platform to store,share and show real-time distribution range and population abundance data. 展开更多
关键词 Black-faced Spoonbill Breeding distribution Coastal mudflats Conservation status Platalea minor Population abundance Winter distribution Yangtze River floodplain
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Rational design of hollow oxygen deficiency-enriched NiFe_(2)O_(4)@N/rGO as bifunctional electrocatalysts for overall water splitting 被引量:3
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作者 lei cao Zhenhuan Li +2 位作者 Kunmei Su Maliang Zhang Bowen Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第3期595-603,共9页
Bimetallic metal organic framework(MOF)as a precursor to prepare catalysts with bifunctional catalytic activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)attracts more and more attention.Her... Bimetallic metal organic framework(MOF)as a precursor to prepare catalysts with bifunctional catalytic activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)attracts more and more attention.Herein,hollow oxygen deficiency-enriched NiFe_(2)O_(4) is synthesized by pyrolytic FeNi bimetallic MOF.The defects of rGO during carbonization can act as nucleation sites for FeNi particles.After nucleation and N doping,the FeNi particles were served as catalysts for the deposition of dissolved carbon in the defects of the N/rGO.These deposited carbon,like a bridge,connect N/rGO and hollow oxygen deficiency-enriched NiFe_(2)O_(4) together,which giving full play to the advantages of N/rGO in fast electron transfer,thereby improving its catalytic activity.The resultant NiFe_(2)O_(4)@N/rGO-800 exhibits a low overpotential of 252 mV at 20 mA cm^(-2) for OER and 157 mV at 10 mA cm^(-2) for HER in 1 M KOH,respectively.When used as bifunctional electrodes for overall water splitting,it also shows low cell voltage of 1.60 V and 1.67 V at 10 and 20 mA cm^(-2),respectively. 展开更多
关键词 Oxygen deficiency Hollow NiFe_(2)O_(4) N/rGO Bifunctional electrocatalyst Overall water splitting
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Size matters: wintering ducks stay longer and use fewer habitats on largest Chinese lakes 被引量:4
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作者 Fanjuan Meng Hongbin Li +4 位作者 Xin Wang lei Fang Xianghuang Li lei cao Anthony David Fox 《Avian Research》 CSCD 2019年第4期415-422,共8页
Background:Evidence suggests that wintering waterbirds have become conspicuously more concentrated at two largest lakes of the Yangtze River Floodplain,East Dong Ting Lake(Hunan Province,29°20′N,113°E)and P... Background:Evidence suggests that wintering waterbirds have become conspicuously more concentrated at two largest lakes of the Yangtze River Floodplain,East Dong Ting Lake(Hunan Province,29°20′N,113°E)and Poyang Lake(Jiangxi Province,29°N,116°20′E),relative to other lakes,despite the establishment of reserves elsewhere.While this relationship is likely due to greater extent of undisturbed habitats in larger lakes,we understand little of the drivers affecting individual behaviours behind this tendency.Methods:We tracked wintering movements of three duck species(Eurasian Wigeon Mareca penelope,Falcated Duck M.falcata and Northern Pintail Anas acuta)using GPS transmitters,examining differences between the two largest lakes and other smaller lakes in ducks’habitat use,duration of stay at each lake and the daily distances moved by the tagged birds while at these sites.Results:The Eurasian Wigeon and Falcated Duck stayed five times longer and almost exclusively used natural habitat types at the two large lakes(91‒95%of positions)compared to length of stay time at smaller lakes,where they spent 28‒33 days on average(excluding the capture site)and exploited many more different habitats(including c.50%outside lakes).Conclusions:Our study is the first to show that shorter length of stay and more varied habitat use by ducks at small lakes may contribute to explaining the apparent regional concentration of numbers present of these and other species at the largest lakes in recent years.This compares with their declining abundance at smaller lakes,where habitat loss and degradation has been more manifest than on the larger lakes. 展开更多
关键词 Anas acuta GPS/GSM telemetry Mareca falcata Mareca penelope Winter residency time Yangtze River Floodplain
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Assessing site-safeguard effectiveness and habitat preferences of Bar-headed Geese (Anser indicus) at their stopover sites within the Qinghai-Tibet Plateau using GPS/ GSM telemetry 被引量:5
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作者 Junjian Zhang Yanbo Xie +6 位作者 Laixing Li Nyambayar Batbayar Xueqin Deng Iderbat Damba Fanjuan Meng lei cao Anthony David Fox 《Avian Research》 CSCD 2020年第4期433-445,共13页
Background:The Bar-headed Goose(Anser indicus)breeds across the high plains and plateau of Central Asia and winters in the Qinghai-Tibet Plateau(QTP),the Yunnan-Guizhou Plateau and the Indian sub-continent.Of the two ... Background:The Bar-headed Goose(Anser indicus)breeds across the high plains and plateau of Central Asia and winters in the Qinghai-Tibet Plateau(QTP),the Yunnan-Guizhou Plateau and the Indian sub-continent.Of the two recognized discrete flyways of the Bar-headed Goose,the Eastern Tibetan Flyway(ETF)is the larger,comprising at least six migration routes.However,we remain ignorant about their migratory connectivity,habitat use and effectiveness of site-safeguard mechanisms set in place for the species.Methods:We tracked 30 ETF Bar-headed Geese from Chinese and Mongolian breeding areas to their wintering grounds using GPS/GSM transmitters,to determine their migration routes and stopover staging patterns within the QTP,overlaying these upon GIS layers of protected area status and habitat type,to model their habitat selection.Results:In total,14 tagged Bar-headed Geese provided information on their entire autumn migration and 4 geese on their entire spring migration.Qinghai Lake marked birds overwintered in the QTP(n=2),geese tagged in Mongolia wintered either in the QTP(n=3)or in India/Bangladesh(n=9),representing three of the migration routes within the ETF.In total,tagged birds staged at 79 different stopover sites within QTP in autumn and 23 in spring,of which 65%(autumn)and 59%(spring)of all fixes fell within the boundaries of either National Nature Reserves(NNRs)or Important Birds Areas(IBAs)in the QTP.Bar-headed Geese predominantly occurred on four land-cover types:grassland(mostly by day),water bodies(at night),wetlands and bare substrates(salt flats,dry lake/river substrates and plough)with little change in proportion.Generalized linear mixed models comparing presence with pseudo-absence data suggested geese strongly selected for wetlands as staging habitat,avoiding bare substrates in spring.Conclusions:Based on our limited observations of these tagged geese,this study is the first to show that the current designated National Nature Reserves in place in the staging areas within the QTP appear adequate to protect this increasing population.In addition,Hala Lake in Qinghai Province and adjacent areas used as initial QTP staging during autumn migration(currently outside of designated as NNRs/IBAs)are recommended for protection,based on their use by tagged birds from this study.Habitat modelling confirmed the importance of natural wetlands as feeding areas and safe areas of open water as roosting places. 展开更多
关键词 Anser indicus Bar-headed goose Habitat use Habitat selection Important bird area National nature reserve
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A potential distribution map of wintering Swan Goose(Anser cygnoides)in the middle and lower Yangtze River floodplain,China 被引量:3
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作者 An An Yong Zhang +2 位作者 lei cao Qiang Jia Xin Wang 《Avian Research》 CSCD 2018年第4期344-353,共10页
Background: Reliable information on the distribution of target species and influencing environmental factors is essential for effective conservation management. However, ecologists have often derived data from costly ... Background: Reliable information on the distribution of target species and influencing environmental factors is essential for effective conservation management. However, ecologists have often derived data from costly field surveys. The Swan Goose(Anser cygnoides), a vulnerable Anatidae species, winters almost exclusively in China's Yangtze River floodplain, but wintering numbers have been steadily decreasing. To better safeguard this unique species, modern modeling approaches can be used to quantify and predict its suitable wintering habitat. Specifically, a potential wintering distribution map of this species is critically important.Methods: This study used the maximum entropy approach to model a distribution map of this species. In total, data from 97 up-to-date sites were extracted from 1263 survey sites(excluding duplicate data). After eliminating spatial autocorrelation, 11 environmental variables, including factors related to climate, land structure, vegetation, and anthropogenic activities, were used for model prediction.Results: The prediction distribution map shows that the population has concentrated mainly in the boundary area of Anhui, Hubei, and Jiangxi provinces, especially along the Yangtze River. Modeling results suggest that areas within the middle and lower Yangtze River floodplain, such as those in Hunan and Hubei provinces and the eastern coastal area of Zhejiang Province, demonstrate a potential level of "medium" suitability for this species to winter.Conclusions: Results from this study provide fundamental information for the restoration and management of the Swan Goose. Our "visualized" potential distribution map can assist in planning optimal conservation strategies, and consequently may help to increase the number of wintering populations in China. 展开更多
关键词 SWAN Goose Species distribution map MAXENT Ecological conservation management
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Wintering Swan Geese maximize energy intake through substrate foraging depth when feeding on buried Vallisneria natans tubers 被引量:2
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作者 Yan Chen Yong Zhang +2 位作者 lei cao Willem F.de Boer Anthony D.Fox 《Avian Research》 CSCD 2019年第2期163-170,共8页
Background: Foraging theory predicts that animals select patches that offer the highest net rate of energy gain. Hence, prey distribution patterns and spatiotemporal heterogeneity play important roles in determining a... Background: Foraging theory predicts that animals select patches that offer the highest net rate of energy gain. Hence, prey distribution patterns and spatiotemporal heterogeneity play important roles in determining animal feeding patch selection. For waterfowl foraging on buried aquatic plant tubers, the distribution and biomass of these plant organs vary with depth in the substrate. Since excavation costs also increase with depth, the energy intake of the animals foraging on these plants is highly sediment depth dependent. Methods: Here, using observations of Swan Geese (Anser cygnoides) foraging on Vallisneria natans tubers, we test our hypothesis that geese feeding on tubers buried at intermediate sediment depth maximize their daily energy intake because of the interaction between tuber size and abundance with depth. To do this, we measured the distribution patterns of buried Vallisneria tubers under both undisturbed conditions and post-exploitation by geese (i.e. giving-up conditions). We investigated the relationship between tuber size and burial depth, and total tuber biomass within each sediment layer in undisturbed and exploited plots. Finally, we compared modelled Swan Goose daily energy intake feeding on Vallisneria tubers buried at different sediment layers (1–10, 11–20 and 21–30 cm below the surface). Results: Dry weight of Vallisneria tubers linearly increased with burial depth, while average total dry weight density of tubers showed a unimodal relationship, peaking at intermediate levels. Not surprisingly, Swan Geese foraged most intensively on tubers buried at intermediate sediment depths, where they maximize their daily energy intake. Our results support our hypothesis that Swan Geese feeding on tubers at intermediate depths maximize their daily energy intake. Conclusions: Our study is the first to quantify foraging strategies of Swan Geese during the wintering period, emphasizing the importance of plant traits on foraging selection of belowground foragers. 展开更多
关键词 Energetic trade-off Optimal FORAGING Shengjin Lake SUBSTRATE Tuber burial DEPTH Yangtze River
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Effects of diazepam on glutamatergic synaptic transmission in the hippocampal CA1 area of rats with traumatic brain injury 被引量:1
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作者 lei cao Xiaohua Bie +3 位作者 Su Huo Jubao Du Lin Liu Weiqun Song 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第21期1897-1901,共5页
The activity of the Schaffer collaterals of hippocampal CA3 neurons and hippocampal CA1 neurons has been shown to increase after fluid percussion injury. Diazepam can inhibit the hyperexcitability of rat hippocampal n... The activity of the Schaffer collaterals of hippocampal CA3 neurons and hippocampal CA1 neurons has been shown to increase after fluid percussion injury. Diazepam can inhibit the hyperexcitability of rat hippocampal neurons after injury, but the mechanism by which it affects excitatory synaptic transmission remains poorly understood. Our results showed that diazepam treatment significantly increased the slope of input-output curves in rat neurons after fluid percussion injury. Diazepam significantly decreased the numbers of spikes evoked by super stimuli in the presence of 15 μmol/L bicuculline, indicating the existence of inhibitory pathways in the injured rat hippocampus. Diazepam effectively increased the paired-pulse facilitation ratio in the hippocampal CA1 region following fluid percussion injury, reduced miniature excitatory postsynaptic potentials, decreased action-potential-dependent glutamine release, and reversed spontaneous glutamine release. These data suggest that diazepam could decrease the fluid percussion injury-induced enhancement of excitatory synaptic transmission in the rat hippocampal CA1 area. 展开更多
关键词 海马CA1区 突触传递 地西泮 大鼠脑 兴奋性突触后电位 谷氨酸 海马神经元 冲击损伤
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Functional recovery of injured sciatic nerve by intraperitoneal injection of multiwalled carbon nanotubes 被引量:1
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作者 Qigang Yang Qiong Zhang +3 位作者 Yongping Chen lei cao Wei Jiang Guihai Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第7期505-509,共5页
Some evidence suggests that multiwalled carbon nanotubes can promote neuronal differentiation and growth. The present study investigated the effect of functional multiwalled carbon nanotubes (MWCNTs) on functional rec... Some evidence suggests that multiwalled carbon nanotubes can promote neuronal differentiation and growth. The present study investigated the effect of functional multiwalled carbon nanotubes (MWCNTs) on functional recovery of injured sciatic nerves in mice. The results revealed that MWCNTs accelerated the recovery of functional index scores of injured sciatic nerves in mice. Moreover, the medullary sheath was significantly thicker in the injured sciatic nerve following MWCNTs administration. These effects were dose-dependent. 展开更多
关键词 多壁碳纳米管 坐骨神经 功能恢复 腹腔注射 损伤 恢复功能 神经功能 神经元
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