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Numerical study on local scour characteristics around submarine pipelines in the Yellow River Delta silty sandy soil under waves and currents 被引量:1
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作者 Peng Yu Ruigeng Hu +4 位作者 Jike Zhang Qi Yang Jieru Zhao lei cao Chenghao Zhu 《Deep Underground Science and Engineering》 2024年第2期182-196,共15页
Due to their high reliability and cost-efficiency,submarine pipelines are widely used in offshore oil and gas resource engineering.Due to the interaction of waves,currents,seabed,and pipeline structures,the soil aroun... Due to their high reliability and cost-efficiency,submarine pipelines are widely used in offshore oil and gas resource engineering.Due to the interaction of waves,currents,seabed,and pipeline structures,the soil around submarine pipelines is prone to local scour,severely affecting their operational safety.With the Yellow River Delta as the research area and based on the renormalized group(RNG)k-εturbulence model and Stokes fifth-order wave theory,this study solves the Navier-Stokes(N-S)equation using the finite difference method.The volume of fluid(VOF)method is used to describe the fluid-free surface,and a threedimensional numerical model of currents and waves-submarine pipeline-silty sandy seabed is established.The rationality of the numerical model is verified using a self-built waveflow flume.On this basis,in this study,the local scour development and characteristics of submarine pipelines in the Yellow River Delta silty sandy seabed in the prototype environment are explored and the influence of the presence of pipelines on hydrodynamic features such as surrounding flow field,shear stress,and turbulence intensity is analyzed.The results indicate that(1)local scour around submarine pipelines can be divided into three stages:rapid scour,slow scour,and stable scour.The maximum scour depth occurs directly below the pipeline,and the shape of the scour pits is asymmetric.(2)As the water depth decreases and the pipeline suspension height increases,the scour becomes more intense.(3)When currents go through a pipeline,a clear stagnation point is formed in front of the pipeline,and the flow velocity is positively correlated with the depth of scour.This study can provide a valuable reference for the protection of submarine pipelines in this area. 展开更多
关键词 local scour numerical simulation submarine pipelines Yellow River Delta
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Treatment of hemolymphangioma by robotic surgery: A case report 被引量:1
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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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An allelic variation in the promoter of the LRR-RLK gene,qSS6.1,is associated with melon seed size
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作者 Xiaoxue Liang Jiyu Wang +11 位作者 lei cao Xuanyu Du Junhao Qiang Wenlong Li Panqiao Wang Juan Hou Xiang Li Wenwen Mao Huayu Zhu Luming Yang Qiong Li Jianbin Hu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3522-3536,共15页
Seed size is an important agronomic trait in melons that directly affects seed germination and subsequent seedling growth.However,the genetic mechanism underlying seed size in melon remains unclear.In the present stud... Seed size is an important agronomic trait in melons that directly affects seed germination and subsequent seedling growth.However,the genetic mechanism underlying seed size in melon remains unclear.In the present study,we employed Bulked-Segregant Analysis sequencing(BSA-seq)to identify a candidate region(~1.35 Mb)on chromosome 6 that corresponds to seed size.This interval was confirmed by QTL mapping of three seed size-related traits from an F2 population across three environments.This mapping region represented nine QTLs that shared an overlapping region on chromosome 6,collectively referred to as qSS6.1.New InDel markers were developed in the qSS6.1 region,narrowing it down to a 68.35 kb interval that contains eight annotated genes.Sequence variation analysis of the eight genes identified a SNP with a C to T transition mutation in the promoter region of MELO3C014002,a leucine-rich repeat receptor-like kinase(LRR-RLK)gene.This mutation affected the promoter activity of the MELO3C014002 gene and was successfully used to differentiate the large-seeded accessions(C-allele)from the small-seeded accessions(T-allele).qRT-PCR revealed differential expression of MELO3C014002 between the two parental lines.Its predicted protein has typical LRR-RLK family domains,and phylogenetic analyses reveled its similarity with the homologs in several plant species.Altogether,these findings suggest MELO3C014002 as the most likely candidate gene involved in melon seed size regulation.Our results will be helpful for better understanding the genetic mechanism regulating seed size in melons and for genetically improving this important trait through molecular breeding pathways. 展开更多
关键词 MELON QTL mapping seed size candidate gene allelic variation
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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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Risk factors and clinical significance of posterior slip of the proximal vertebral body after lower lumbar fusion
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作者 Jia-Jun Zhu Yi Wang +5 位作者 Jun Zheng Sheng-Yang Du lei cao Yu-Ming Yang Qing-Xi Zhang Ding-Ding Xie 《World Journal of Clinical Cases》 SCIE 2024年第26期5885-5892,共8页
BACKGROUND Adjacent segment disease(ASD)after fusion surgery is frequently manifests as a cranial segment instability,disc herniation,spinal canal stenosis,spondylolisthesis or retrolisthesis.The risk factors and mech... BACKGROUND Adjacent segment disease(ASD)after fusion surgery is frequently manifests as a cranial segment instability,disc herniation,spinal canal stenosis,spondylolisthesis or retrolisthesis.The risk factors and mechanisms of ASD have been widely discussed but never clearly defined.AIM To investigate the risk factors and clinical significance of retrograde movement of the proximal vertebral body after lower lumbar fusion.METHODS This was a retrospective analysis of the clinical data of patients who underwent transforaminal lumbar interbody fusion surgery between September 2015 and July 2021 and who were followed up for more than 2 years.Ninety-one patients with degenerative lumbar diseases were included(22 males and 69 females),with an average age of 52.3 years(40-73 years).According to whether there was retrograde movement of the adjacent vertebral body on postoperative X-rays,the patients were divided into retrograde and nonretrograde groups.The sagittal parameters of the spine and pelvis were evaluated before surgery,after surgery,and at the final follow-up.At the same time,the Oswestry Disability Index(ODI)and Visual Analogue Scale(VAS)were used to evaluate the patients’quality of life.RESULTS Nineteen patients(20.9%)who experienced retrograde movement of proximal adjacent segments were included in this study.The pelvic incidence(PI)of the patients in the retrograde group were significantly higher than those of the patients in the nonretrograde group before surgery,after surgery and at the final follow-up(P<0.05).There was no significant difference in lumbar lordosis(LL)between the two groups before the operation,but LL in the retrograde group was significantly greater than that in the nonretrograde group postoperatively and at the final follow-up.No significant differences were detected in terms of the|PI–LL|,and there was no significant difference in the preoperative lordosis distribution index(LDI)between the two groups.The LDIs of the retrograde group were 68.1%±11.5%and 67.2%±11.9%,respectively,which were significantly lower than those of the nonretrograde group(75.7%±10.4%and 74.3%±9.4%,respectively)(P<0.05).Moreover,the patients in the retrograde group had a greater incidence of a LDI<50%than those in the nonretrograde group(P<0.05).There were no significant differences in the ODI or VAS scores between the two groups before the operation,but the ODI and VAS scores in the retrograde group were significantly worse than those in the nonretrograde group after the operation and at the last follow-up,(P<0.05).CONCLUSION The incidence of posterior slippage after lower lumbar fusion was approximately 20.9%.The risk factors are related to a higher PI and distribution of lumbar lordosis.When a patient has a high PI and insufficient reconstruction of the lower lumbar spine,adjacent segment compensation via posterior vertebral body slippage is one of the factors that significantly affects surgical outcomes. 展开更多
关键词 Adjacent segment disease Posterior vertebral slip Sagittal alignment of spine-pelvis Lower lumbar fusion Quality of life
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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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Investigation of low-temperature hydrothermal stability of Cu-SAPO-34 for selective catalytic reduction of NO_x with NH_3 被引量:10
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作者 Xiao Xiang Pengfei Wu +5 位作者 Yi cao lei cao Quanyi Wang Shutao Xu Peng Tian Zhongmin Liu 《Chinese Journal of Catalysis》 EI CSCD 北大核心 2017年第5期918-927,共10页
The low‐temperature hydrothermal stabilities of Cu‐SAPO‐34samples with various Si contents and Cu loadings were systematically investigated.The NH3oxidation activities and NH3‐selective catalytic reduction(SCR)act... The low‐temperature hydrothermal stabilities of Cu‐SAPO‐34samples with various Si contents and Cu loadings were systematically investigated.The NH3oxidation activities and NH3‐selective catalytic reduction(SCR)activities(mainly the low‐temperature activities)of all the Cu‐SAPO‐34catalysts declined after low‐temperature steam treatment(LTST).These results show that the texture and acid density of Cu‐SAPO‐34can be better preserved by increasing the Cu loading,although the hydrolysis of Si-O-Al bonds is inevitable.The stability of Cu ions and the stability of the SAPO framework were positively correlated at relatively low Cu loadings.However,a high Cu loading(e.g.,3.67wt%)resulted in a significant decrease in the number of isolated Cu ions.Aggregation of CuO particles also occurred during the LTST,which accounts for the decreasing NH3oxidation activities of the catalysts.Among the catalysts,Cu‐SAPO‐34with a high Si content and medium Cu content(1.37wt%)showed the lowest decrease in NH3‐SCR because its Cu2+content was well retained and its acid density was well preserved. 展开更多
关键词 Cu‐SAPO‐34 Low temperature hydrothermal stability Nitrogen oxides Selective catalytic reduction Ammonia oxidation
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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:11
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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:4
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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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A reconstruction strategy for the synthesis of Cu-SAPO-34 with excellent NH-SCR catalytic performance and hydrothermal stability 被引量:3
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作者 Lijing Sun Miao Yang +6 位作者 Yi cao Peng Tian Pengfei Wu lei cao Shutao Xu Shu Zeng Zhongmin Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第9期1410-1420,共11页
A reconstruction strategy has been developed to synthesize Cu-SAPO-34 with a wide crystallization phase region,high solid yield,and tunable Si and Cu contents.Cu-rich SAPO-34 was prepared from a Cu-amine complex,which... A reconstruction strategy has been developed to synthesize Cu-SAPO-34 with a wide crystallization phase region,high solid yield,and tunable Si and Cu contents.Cu-rich SAPO-34 was prepared from a Cu-amine complex,which acted as a precursor and Cu source for the reconstruction synthesis.The role of the Cu-amine complex as a template was restricted,which allowed easier control over the Cu and Si contents than in the previously reported"one-pot"synthesis method.Characterization of the material revealed that the Si(4Al)coordination environment dominates the synthesized Cu-SAPO-34 catalysts.High-temperature hydrothermal treatment increased the isolated Cu2+content slightly,and the acid sites in the low-silica catalyst are more resistant to hydrothermal treatment than those of the existing catalysts.The obtained materials,especially the low-silica Cu-SAPO-34 sample,exhibit excellent catalytic activity and hydrothermal stability for the selective catalytic reduction of NOx by NH3(NH3-SCR).In addition,the influence of the catalyst acidity on the NH3-SCR reaction was also investigated and is discussed.The high synthetic efficiency and outstanding catalytic performance make Cu-SAPO-34 synthesized by the reconstruction method a promising catalyst for the NH3-SCR process. 展开更多
关键词 Cu-SAPO-34 Hydrothermal synthesis NH3-SCR Hydrothermal stability CRYSTALLIZATION
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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:7
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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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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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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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Cyclical helping hands: seasonal tailwinds differentially affect migrating Oriental Storks (Ciconia boyciana) travel speed 被引量:4
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作者 Shujuan Fan Qingshan Zhao +5 位作者 Hongbin Li Baoguang Zhu Shubin Dong Yanbo Xie lei cao Anthony David Fox 《Avian Research》 CSCD 2020年第2期83-91,共9页
Background:The Oriental Stork(Ciconia boyciana)breeds in southeastern Siberia and parts of northeast China,and winters mainly in southeast China.Although the autumn migration pattern of Oriental Storks has been previ-... Background:The Oriental Stork(Ciconia boyciana)breeds in southeastern Siberia and parts of northeast China,and winters mainly in southeast China.Although the autumn migration pattern of Oriental Storks has been previ-ously described,differences between spring and autumn migration travel speed in relation to wind assistance were unknown.Methods:Using GPS/GSM transmitters,we tracked the full migrations of 18 Oriental Storks during 2015-2018 to compare differences in autumn and spring migration patterns,and combined the satellite telemetry data with the National Center for Environmental Prediction Reanalysis data to explain the relationship between 850 mbar wind vec-tors and seasonal differences in travel speed.Results:Differences in tailwinds contributed to significant differences in daily average Oriental Storks travel speed in spring(258.11±64.8 km/day)compared to autumn(172.23±49.7 km/day,p<0.001).Storks stopped significantly more often in autumn than spring(1.78±1.1 versus 1.06±0.9,p<0.05),but stopover duration(15.52±12.4 versus 16.30±15.1 days,respectively,p=0.3)did not differ significantly.Tailwinds at 850 mbar pressure level(extracted from the National Center of Environmental Prediction Reanalysis data archive)significantly affected daily flying speed dur-ing spring and autumn migration.Tailwind conditions in spring(mean 4.40±5.6 m/s)were always more favourable than in autumn when they received no net benefit(0.48±5.6 m/s,p<0.001).Despite mean spring migration dura-tion being less than autumn(27.52±15.9 versus 32.77±13.4 days,p=0.17),large individual variation meant that this duration did not differ significantly from each other.Conclusions:For long distance migratory soaring birds(such as storks),relative duration of spring and autumn migration likely relates to the interaction between imperative for earliest arrival to breeding grounds and seasonal meteorological conditions experienced en route. 展开更多
关键词 Ciconia boyciana GPS/GSM tracking Migration Tailwind Travel duration Travel speed
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