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Parallel Vision ■ Image Synthesis/Augmentation 被引量:1
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作者 wenwen zhang Wenbo Zheng +1 位作者 Qiang Li Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期782-784,共3页
Dear Editor,Scene understanding is an essential task in computer vision.The ultimate objective of scene understanding is to instruct computers to understand and reason about the scenes as humans do.Parallel vision is ... Dear Editor,Scene understanding is an essential task in computer vision.The ultimate objective of scene understanding is to instruct computers to understand and reason about the scenes as humans do.Parallel vision is a research framework that unifies the explanation and perception of dynamic and complex scenes. 展开更多
关键词 instru EXPLANATION COMPUTER
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Effects of Dietary Changes on the Gut Microbiota of Cynops orientalis
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作者 Yuting WANG Yuning XIE +12 位作者 Siyu WU wenwen zhang Xiner CHENG Zixuan LI Fangfei HAN Jiayi SHI Yingying SHI Zhirong HE Chunna zhang Yixin JIANG Na ZHAO Jiaqi LI Supen WANG 《Asian Herpetological Research》 SCIE CSCD 2024年第2期63-72,共10页
The gut microbiota plays a pivotal role in the maintenance of health for amphibians,and it has been fully recognized,but the effectiveness of various influencing factors has not yet been fully clarified.Although this ... The gut microbiota plays a pivotal role in the maintenance of health for amphibians,and it has been fully recognized,but the effectiveness of various influencing factors has not yet been fully clarified.Although this association should be considered while the amphibian order Caudata is facing a severe situation of population decline and extinction,there is little understanding of the association between diets and the diversity of gut microbiota in the amphibian order Caudata.Here,we conducted an extensive analysis of the gut microbiota of Cynops orientalis fed different diets using functional prediction and 16S rRNA amplicon sequencing techniques.First,we found that wild individuals had greater gut microbial diversity and richness in comparison to captive individuals.Second,we identified the bacterial taxa associated with diets and observed differences in the relative abundance of gut microbiota among people on various diets.Finally,we have a predictive comprehension of the selection and adaptative significance of shared core ASVs in the gut microbiota in maintaining the healthy survival of C.orientalis in a large-scale spatiotemporal map.Our study emphasizes how diets alter the gut microbiota of Caudata and offers fresh perspectives on the conservation and captive management of species in Caudata. 展开更多
关键词 16S rRNA CAUDATA core microbiota DIET gut microbiota
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Establishment and characterization of a canine chondrosarcoma cell line:Mango
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作者 Meilin Wang Xiao Wang +8 位作者 Lixin He Hongbo Gao Wenxuan Li Huili Feng Qingyuan Zhao wenwen zhang Chengzong Li Bohan zhang Changwei Qiu 《Animal Diseases》 CAS 2024年第3期186-197,共12页
In the global progress of bone tumor research,established stable and long-lasting transgenic chondrosarcoma(CSA)cell lines are rare,mainly of murine and human origin,while the establishment of canine CSA cell lines ha... In the global progress of bone tumor research,established stable and long-lasting transgenic chondrosarcoma(CSA)cell lines are rare,mainly of murine and human origin,while the establishment of canine CSA cell lines has yet to be reported.This study established a canine CSA cell line to facilitate the basic clinical study of canine CSA.Fifty fve cases of canine osteolytic disease were collected,and more than 10 bone tumor samples from dogs with typical clinical signs were used for primary cell culture.A cell line with stable passaging for more than 100 generations and mouse tumorigenic ability was successfully cultured.According to the clinical characteristics of the dog and the histopathological results of the primary tumor,CSA was diagnosed,and the CSA cell line was designated Mango.Immunohistochemical(IHC)results showed that the immunoreactivity of bone gamma-carboxyglutamate protein(BGLAP),secreted protein acidic and rich in cysteine(SPARC),alkaline phosphatase(ALPL),vimentin(VIM)and S100 were positive.However,the immunoreactivity of pan-cytokeratin(PCK),chromogranin A(CGA),and platelet endothelial cell adhesion molecule-1(CD31)was negative.Immunofuorescence(IF)results showed that the protein expressions in the Mango cell line were consistent with the IHC identifcation of the primary tumor.The Mango cell line’s doubling time was 43.92 h,and the cell formation rate exceeded 20%.There were abnormal chromosome numbers,hetero staining with toluidine blue,and certain calcifcation abilities.It could be passaged stably and continuously without changing the cell morphology and characteristics.In vivo,the cells were successfully injected into the nude mice model with a tumorigenic rate of 100%.The immunophenotype of the xenograft tumor was consistent with that of the primary tumor.Therefore,we efectively established a canine CSA cell line.As a promising cell material,this cell line can be used to construct a tumor-bearing model conducive to the subsequent basic research of canine CSA.Moreover,because of its similarity to human CSA,the animal model of CSA is also indispensable for investigating human CSA. 展开更多
关键词 Canine chondrosarcoma Cell line ESTABLISHMENT CHARACTERIZATION Tumorigenicity
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Association of overall survival benefit of radiotherapy with progression-free survival after chemotherapy for diffuse large B-cell lymphoma:A systematic review and meta-analysis
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作者 Jingnan Wang Xin Liu +21 位作者 Yunpeng Wu Qiuzi Zhong Tao Wu Yong Yang Bo Chen Hao Jing Yuan Tang Jing Jin Yueping Liu Yongwen Song Hui Fang Ningning Lu Ning Li Yirui Zhai wenwen zhang Min Deng Shulian Wang Fan Chen Lin Yin Chen Hu Shunan Qi Yexiong Li 《Journal of the National Cancer Center》 2024年第3期249-259,共11页
Objective:To evaluate whether improved progression-free survival(PFS)from radiotherapy(RT)translates into an overall survival(OS)benefit for diffuse large B-cell lymphoma(DLBCL).Methods:A systematic literature search ... Objective:To evaluate whether improved progression-free survival(PFS)from radiotherapy(RT)translates into an overall survival(OS)benefit for diffuse large B-cell lymphoma(DLBCL).Methods:A systematic literature search identified randomized controlled trials(RCTs)and retrospective studies that compared combined-modality therapy(CMT)with chemotherapy(CT)alone.Weighted regression analyses were used to estimate the correlation between OS and PFS benefits.Cohen’s kappa statistic assessed the consis-tency between DLBCL risk-models and PFS patterns.Furthermore,the benefit trend of RT was analyzed by fitting a linear regression model to the pooled hazard ratio(HR)according to the PFS patterns.Results:For both 7 RCTs and 52 retrospective studies,correlations were found between PFS HR(HRPFS)and OS HR(HROS)at trial level(r=0.639-0.876),and between PFS and OS rates at treatment-arm level,regardless of CT regimens(r=0.882-0.964).Incorporating RT into CT increased about 18%of PFS,and revealed a different OS benefit profile.Patients were stratified into four CT-generated PFS patterns(>80%,>60-80%,>40-60%,and≤40%),which was consistent with risk-stratified subgroups(kappa>0.6).Absolute gain in OS from RT ranged from≤5%at PFS>80%to about 21%at PFS≤40%,with pooled HROS from 0.70(95%CI,0.51-0.97)to 0.48(95%CI,0.36-0.63)after rituximab-based CT.The OS benefit of RT was predominant in intermediate-and high-risk patients with PFS≤80%.Conclusion:We demonstrated a varied OS benefit profile of RT to inform treatment decisions and clinical trial design. 展开更多
关键词 Diffuse large B-cell lymphoma CHEMOTHERAPY RADIOTHERAPY Risk-benefit
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显示与能源领域功能高分子薄膜拉伸加工的研究进展 被引量:2
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作者 安敏芳 万彩霞 +6 位作者 张文文 张前磊 吴福胜 柳青 王道亮 孟令蒲 李良彬 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第1期307-316,共10页
随着战略新兴产业如新型显示、新能源等的兴起,功能高分子薄膜的加工环境越来越复杂、条件越来越苛刻。但是,拉伸加工仍然是功能高分子薄膜性能提高、功能化的重要环节,研究这类高分子薄膜拉伸加工过程中的结构演变对提高薄膜的性能具... 随着战略新兴产业如新型显示、新能源等的兴起,功能高分子薄膜的加工环境越来越复杂、条件越来越苛刻。但是,拉伸加工仍然是功能高分子薄膜性能提高、功能化的重要环节,研究这类高分子薄膜拉伸加工过程中的结构演变对提高薄膜的性能具有非常重要的指导意义。文中总结了近年来新型显示和新能源领域功能高分子薄膜拉伸加工的研究进展,涉及的功能高分子薄膜包括聚乙烯醇(PVA)偏光膜、三醋酸纤维素酯(TAC)光学补偿膜、聚对苯二甲酸乙二醇酯(PET)光学膜、PP电池隔膜和PE电池隔膜。最后对高分子薄膜拉伸加工的研究手段和方法进行了总结和展望。 展开更多
关键词 光学膜 电池隔膜 拉伸加工 同步辐射X射线散射技术 结构演变
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基于梳状结构的复杂交联聚己内酯的合成及形状记忆行为 被引量:2
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作者 王怡莹 冷雪菲 +2 位作者 张稳稳 高梦云 李杨 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第4期158-165,共8页
以正丁基锂为引发剂,通过活性阴离子聚合得到窄分布的聚丁二烯,然后通过环氧化和羟基化反应得到多羟基聚丁二烯。并以多羟基聚丁二烯作为大分子引发剂,通过开环聚合方法合成了梳状聚己内酯(gPCL),通过核磁共振波谱和凝胶渗透色谱测定结... 以正丁基锂为引发剂,通过活性阴离子聚合得到窄分布的聚丁二烯,然后通过环氧化和羟基化反应得到多羟基聚丁二烯。并以多羟基聚丁二烯作为大分子引发剂,通过开环聚合方法合成了梳状聚己内酯(gPCL),通过核磁共振波谱和凝胶渗透色谱测定结构信息,证明得到了分子量分布窄(PDI<1.18)的具有接枝结构的梳状聚己内酯。通过合成的梳状聚己内酯与六甲基二异氰酸酯(HDI)进行交联反应合成了一系列基于梳状结构的复杂交联聚己内酯(C-gPCL)。利用傅里叶变换红外光谱、差示扫描量热仪、广角X射线衍射、动态力学热分析仪、万能拉伸机等测试方法对获得的交联聚合物的性能进行了表征并对交联聚合物的形状记忆行为进行了分析。交联后的聚合物具有热致形状记忆效应,初始形变量为50%时,形状固定率可达99.6%,12 s即可回复形状且形状回复率可达98.8%;高支化结构的引入使得材料形状记忆效应更稳定,经过5次形状记忆过程循环后(单次形变量为50%),形状固定率仍达92.2%,形状回复率达93.6%。 展开更多
关键词 梳状聚合物 交联网状 聚己内酯 形状记忆性能
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BMP signaling in mesenchymal stem cell differentiation and bone formation 被引量:28
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作者 Maureen Beederman Joseph D. Lamplot +18 位作者 Guoxin Nan Jinhua Wang Xing Liu Liangjun Yin Ruidong Li Wei Shui Hongyu zhang Stephanie H. Kim wenwen zhang Jiye zhang Yuhan Kong Sahitya Denduluri Mary Rose Rogers Abdullah Pratt Rex C. Haydon Hue H. Luu Jovito Angeles Lewis L. Shi Tong-Chuan He 《Journal of Biomedical Science and Engineering》 2013年第8期32-52,共21页
Bone morphogenetic proteins (BMPs) are members of the TGF-β superfamily and have diverse functions during development and organogenesis. BMPs play a major role in skeletal development and bone formation, and disrupti... Bone morphogenetic proteins (BMPs) are members of the TGF-β superfamily and have diverse functions during development and organogenesis. BMPs play a major role in skeletal development and bone formation, and disruptions in BMP signaling cause a variety of skeletal and extraskeletal anomalies. Several knockout models have provided insight into the mechanisms responsible for these phenotypes. Proper bone formation requires the differentiation of osteoblasts from mesenchymal stem cell (MSC) precursors, a process mediated in part by BMP signaling. Multiple BMPs, including BMP2, BMP6, BMP7 and BMP9, promote osteoblastic differentiation of MSCs both in vitro and in vivo. BMP9 is one of the most osteogenic BMPs, yet it is a poorly characterized member of the BMP family. Several studies demonstrate that the mechanisms controlling BMP9-mediated osteogenesis differ from other osteogenic BMPs, but little is known about these specific mechanisms. Several pathways critical to BMP9-mediated osteogenesis are also important in the differentiation of other cell lineages, including adipocytes and chondrocytes. BMP9 has also demonstrated translational promise in spinal fusion and bone fracture repair. This review will summarize our current knowledge of BMP-mediated osteogenesis, with a focus on BMP9, by presenting recently completed work which may help us to further elucidate these pathways. 展开更多
关键词 BMP BMP9 Bone Regeneration IGF OSTEOGENESIS TGF-β Wnt Signal TRANSDUCTION MESENCHYMAL Stem Cells MSCS
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Benefit of everolimus as a monotherapy for a refractory breast cancer patient bearing multiple genetic mutations in the PI3K/AKT/mTOR signaling pathway 被引量:6
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作者 Yehui Shi wenwen zhang +6 位作者 Yingnan Ye Yanan Cheng Lei Han Pengpeng Liu Weipeng Zhao Zhongsheng Tong Jinpu Yu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2018年第3期314-321,共8页
A postmenopausal patient with a diagnosis of estrogen receptor(ER)(+), progesterone receptor(PR)(+), and human epidermal growth factor receptor-2(HER2)(-) breast cancer was reported. The patient refused surgery and wa... A postmenopausal patient with a diagnosis of estrogen receptor(ER)(+), progesterone receptor(PR)(+), and human epidermal growth factor receptor-2(HER2)(-) breast cancer was reported. The patient refused surgery and was resistant to conventional chemotherapy regimens. Computed tomography and the circulating tumor cell test indicated that the patient's tumor burden increased rapidly even after several chemotherapy sessions. Multiple genetic aberrances in the phosphatidylinositol3-kinases(PI3 K) signaling pathway were detected via next-generation sequencing(NGS)-based liquid biopsy, including a p. G1007 R missense mutation in exon 21 of PIK3 CA(33.61%), a p.L70 fs frameshift mutation in exon 3 of phosphatase and tension homolog deleted on chromosome ten(PTEN)(49.14%), and a p. D1542 Y missense mutation in exon 32 of mammalian target of rapamycin(m TOR)(1.66%). Therefore, only the m TOR inhibitor everolimus was administered to the patient. Partial remission(PR) was observed after 2 months, and sustained stable disease(SD) was observed after a year and a half. Subsequent sequencing showed that the mutation ratio of PIK3 CA decreased to 4.17%, and that the PTEN and m TOR mutations disappeared, which revealed the significant curative effect of everolimus. We report the first case of successful monotherapy treatment using everolimus in a patient with advanced breast cancer bearing mutations in genes involved in the PI3 K/ARK/m TOR signaling pathway. The success of this case highlights the invaluable clinical contribution of NGS-based liquid biopsy, as it successfully provided an optimal therapeutic target for the patient with advanced breast cancer. 展开更多
关键词 Breast cancer EVEROLIMUS next-generation sequencing liquid biopsy PI3K/AKT/MTOR
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Revalidation of a prognostic score model based on complete blood count for nasopharyngeal carcinoma through a prospective study 被引量:4
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作者 Xiaohui Li Hui Chang +5 位作者 Yalan Tao Xiaohui Wang Jin Gao wenwen zhang Chen Chen Yunfei Xia 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2016年第5期467-477,共11页
Objective: In our previous work, we incorporated complete blood count (CBC) into TNM stage to develop a new prognostic score model, which was validated to improve prediction efficiency of TNM stage for nasopharynge... Objective: In our previous work, we incorporated complete blood count (CBC) into TNM stage to develop a new prognostic score model, which was validated to improve prediction efficiency of TNM stage for nasopharyngeal carcinoma (NPC). The purpose of this study was to revalidate the accuracy of the model, and its superiority to TNM stage, through data from a prospective study.Methods: CBC of 249 eligible patients from the 863 Program No. 2006AA02Z4B4 was evaluated. Prognostic index (PI) of each patient was calculated according to the score model. Then they were divided by the PI into three categories: the low-, intermediate-and high-risk patients. The 5-year disease-specific survival (DSS) of the three categories was compared by a log-rank test. The model and TNM stage (Tth edition) were compared on efficiency for predicting the 5-year DSS, through comparison of the area under curve (AUC) of their receiver-operating characteristic curves.Results: The 5-year DSS of the low-, intermediate- and high-risk patients were 96.0%, 79.1% and 62.2%, respectively. The low- and intermediate-risk patients had better DSS than the high-risk patients (P〈0.001 and P〈0.005, respectively). And there was a trend of better DSS in the low-risk patients, compared with the intermediate-risk patients (P=0.049). The AUC of the model was larger than that of TNM stage (0.726 vs. 0.661, P:0.023). Conclusions: A CBC-based prognostic score model was revalidated to be accurate and superior to TNM stage on predicting 5-year DSS of NPC. 展开更多
关键词 Complete blood count score model revalidadon disease-specific survival nasopharyngeal carcinoma
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Hardening effect and precipitation evolution of an isothermal aged Mg-Sm based alloy 被引量:2
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作者 Kai Guan Chuang Li +7 位作者 Zhizheng Yang Yongsen Yu Qiang Yang wenwen zhang Zhiping Guan Cheng Wang Min Zha Huiyuan Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第12期4619-4627,共9页
The age-hardening behavior and precipitation evolution of an isothermal aged Mg-5Sm-0.6Zn-0.5Zr(wt.%) alloy have been systematically investigated by means of transmission electron microscopy(TEM) and atomic-resolution... The age-hardening behavior and precipitation evolution of an isothermal aged Mg-5Sm-0.6Zn-0.5Zr(wt.%) alloy have been systematically investigated by means of transmission electron microscopy(TEM) and atomic-resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM). The Vickers hardness of the present alloy increases first and then decreases with ageing time. The sample aged at 200 ℃ for 10 h exhibits a peak-hardness of 90.5 HV. In addition to the dominant β_(0)’ precipitate(orthorhombic,a = 0.642 nm, b = 3.336 nm and c = 0.521 nm) formed on {11-20}α planes, a certain number of γ’’ precipitate(hexagonal, a = 0.556 nm and c = 0.431 nm) formed on basal planes are also observed in the peak-aged alloy. Significantly, the basal γ’’ precipitate is more thermostable than prismatic β_(0)’ precipitate in the present alloy. β_(0)’ precipitates gradually coarsened and were even likely to transform into β_(1) phase(face centered cubic, a = 0.73 nm) with the increase of ageing time, which accordingly led to a gradual decrease in number density of precipitates and finally resulted in the decreased hardness and mechanical property in the over-aged alloys. 展开更多
关键词 Magnesium alloys Ageing treatment Microstructure characterization Age-hardening effect PRECIPITATES
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聚丙烯-聚乙烯消光膜体系织态结构形成机理 被引量:2
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作者 陈晓伟 陈商涛 +5 位作者 孟令蒲 王艳芳 南明见 石行波 张文文 李良彬 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第5期13-19,共7页
采用偏光显微镜和热台联用的方法,研究了聚丙烯(PP)-聚乙烯(PE)共混体系降温过程中的相分离和结晶行为。在此共混体系中,PE质量分数为10%~60%,随着PE质量分数增加,结果呈现2种不同的分相形貌特征:PE质量分数为10%~30%时,PE相区分散在连... 采用偏光显微镜和热台联用的方法,研究了聚丙烯(PP)-聚乙烯(PE)共混体系降温过程中的相分离和结晶行为。在此共混体系中,PE质量分数为10%~60%,随着PE质量分数增加,结果呈现2种不同的分相形貌特征:PE质量分数为10%~30%时,PE相区分散在连续相PP中,当PE质量分数为40%~60%时,PE/PP共存,为双连续相。通过对结晶过程形貌特征的转变以及相畴尺寸的定量分析,发现了2种控制表面粗糙程度的机理:在PP为单连续相时,粗糙度主要取决于分散相相畴大小;在PE/PP双连续相的情况下,在互穿网络结构中主要为骨架相互挤压控制。通过比对各拉伸比下的形貌特征,发现静态结晶形成的织态结构在拉伸过程中发生与宏观应变相关的等比放大,表明消光膜表面形貌主要取决于静态结晶过程。为了建立静态结晶形成结构和消光膜雾度的关系,通过共混-挤出-流延-双向拉伸的方法制备了不同PE含量所对应的消光膜样品,通过雾度测试,证明表面粗糙的织态结构为决定雾度的关键,同时证明了静态结晶实验对于消光膜加工过程中雾度控制的指导意义。 展开更多
关键词 消光膜 表面织态结构 相分离 结晶
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Biocontrol of Rhizoctonia solani Kühn Using Fermentative Solution of Streptomyces corchorusii Strain NF0919 被引量:3
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作者 Jinghui YANG wenwen zhang +2 位作者 Hongzhou CHEN Ting XIAO Qinyan WU 《Agricultural Biotechnology》 CAS 2015年第1期59-61,共3页
A strain of Streptomyces corchorusii (NY0919) antagonistic to Rhizoctonia solani Ktthn was isolated, which produced alkyl glycoside with high antifungal activity. To investigate the antifungal activity of Streptomyc... A strain of Streptomyces corchorusii (NY0919) antagonistic to Rhizoctonia solani Ktthn was isolated, which produced alkyl glycoside with high antifungal activity. To investigate the antifungal activity of Streptomyces corchorusii strain NF0919, the treatments amended with the non-sterilized supernatant resulted in the highest growth inhibition rate of about 100% at a concentration of 20%. The antifungal compound, which inhibited the growth of Rhizoctonia solani Kuhn, was extracted by EtOAC and purified by silica gel, Sephadex LH-20 column, and HPLC, where an active fraction was confirmed by LC-MS and NMR techniques. These results suggested that NF0919 had a high potential in the biocontrol of Rhizoctonia solani Kuhn, which was mainly due to surface active agent APG. 展开更多
关键词 Streptomyces corchorusii Antifungal activity Rhizoctonia solani Kuhn Alkyl glycoside
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Fecal DNA metabarcoding reveals the dietary composition of wintering Red-crowned Cranes(Grus japonensis) 被引量:1
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作者 Hongyi Liu Wei Xu +6 位作者 Nan Xu wenwen zhang Haoming Jiang Yongqiang Zhao Changhu Lu Ying Zhu Peng Xu 《Avian Research》 SCIE CSCD 2023年第4期647-655,共9页
Understanding the diet of threatened wildlife is vital for species-specific conservation and habitat management measures.The Red-crowned Crane(Grus japonensis)is a vulnerable bird distributed in Northeast Asia.Previou... Understanding the diet of threatened wildlife is vital for species-specific conservation and habitat management measures.The Red-crowned Crane(Grus japonensis)is a vulnerable bird distributed in Northeast Asia.Previous dietary studies of this bird focused mainly on its plant food composition based on field observations and microhistological identification.Herein,a total of 45 fecal samples were collected in November,December and January(15 fecal samples each month)from wintering cranes,and then subjected to a high throughput sequencing meta-barcoding approach to determine the primary plant(rbcL)and animal(COI)food items in their diet.A total of 230 operational taxonomic units(OTUs)of plant foods and 371 OTUs of animal foods were obtained.The main plant foods in the wintering period were Miscanthus,Zea,and Hordeum genera,which were similar to those in the breeding and the migration periods.Both agricultural and natural plants were detected,indicating a relatively broad dietary niche for this crane species.However,the main animal foods were representatives of Theridiidae,Megascolecidae,and Agelenidae,in sharp contrast to previous studies.The higher number of small terrestrial arthropods in animal foods might be due to the indirect intake of plants.The composition of both plant and animal foods in the diet showed the highest diversity in December,while it was homogeneous in January.The plant of Zea genus became the main source of nutrition in late winter,as supplementary feeding was performed in the reserve,which could help Red-crowned Cranes to get through the cold season.The results obtained in this work would contribute to the development of effective conservation strategies for the Red-crowned Crane. 展开更多
关键词 Dietary composition Dietary niche Metabarcoding Molecular diet analysis Red-crowned Crane
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Bird communities’responses to human-modified landscapes in the southern Anhui Mountainous Area 被引量:1
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作者 Xue Wang Guang Zhu +5 位作者 Haohao Ma Yi Wu wenwen zhang Yong zhang Chunlin Li Willem F.deBoer 《Avian Research》 SCIE CSCD 2022年第1期49-56,共8页
Conversion of natural environments to human-modified landscapes is continuing at an unprecedented rate,exerting fundamental influences on global biodiversity.Understanding how wildlife communities respond to landscape... Conversion of natural environments to human-modified landscapes is continuing at an unprecedented rate,exerting fundamental influences on global biodiversity.Understanding how wildlife communities respond to landscape modifications is critical to improve biodiversity conservation in human-dominated landscapes.In this study,we surveyed bird communities in three common habitats(i.e.,farmland,village,and forest)in the southern Anhui Mountainous Area during summer(August 2019)and winter(December 2020).The diversity metrics and species compositions of the avian communities were compared among the habitats,and the effects of land use composition in these habitats were tested.During the field surveys,we recorded 7599 birds of 120 species along 45 line transects of 1km in length.The land use compositions differed among habitats,and land use diversity was the highest in villages and lowest in forests.The species richness and bird abundance in the two human-dominated habitats(i.e.,farmland and village)were higher than those in forest in both seasons.Bird species composition also differed across habitat types in both seasons.Bird species feeding on vertebrates,fish and carrion,and species feeding on plants and seeds were mainly found in habitats with less construction lands and lower land use diversity,while omnivorous species and species feeding on fruits and nectar or on invertebrates were less affected by these two variables.The indicator species analysis showed that most species associated with forest feed on invertebrates,while species feeding on plants and seeds were more correlated with farmland and village.The results indicated that the conversion of natural habitats to human-dominated landscapes has pronounced impacts on bird communities in the study area.Human-dominated habitats harboured more avian species that deserve conservation attention.Meanwhile,bird conservations should not be relaxed in forests because there were more than 20 species that had a high specificity for forests. 展开更多
关键词 Community composition Habitat changes Human interference Intermediate disturbance hypothesis Species diversity
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A Numerical Study on the Mechanisms Producing Forces on Cylinders Interacting with Stratified Shear Environments 被引量:1
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作者 Yin Wang Lingling Wang +2 位作者 Yong Ji Zhicheng Xi wenwen zhang 《Fluid Dynamics & Materials Processing》 EI 2021年第2期471-485,共15页
A three dimensional(3D)numerical wave flume is used to investigate carefully the ISWs(Internal solitary wave)forces acting on cylinders interacting with a stratified shear environment.Using the Large-Eddy Simulation(L... A three dimensional(3D)numerical wave flume is used to investigate carefully the ISWs(Internal solitary wave)forces acting on cylinders interacting with a stratified shear environment.Using the Large-Eddy Simulation(LES)approach and analyzing the distribution of shear stress and pressure along the surface of the cylinder,the differential pressure resistance and the viscous force are obtained.The method of multiple linear regression analysis is adopted and a comprehensive influence coefficient is determined accordingly to account for the dimensionless forces acting on the cylinder.Results show that the differential pressure resistance on a square cylinder is 1.5 times higher than that on a circular cylinder in the upper layer,while the differential pressure resistance on a square cylinder is 3.5 times larger than that on a circular cylinder in the lower layer.The viscous force is 1–2 orders of magnitude smaller than the differential pressure resistance,which means that the viscous force could be ignored.The comprehensive influence coefficient shows positive correlation with the relative wave height and negative correlation with upper and lower water depth ratio. 展开更多
关键词 Internal solitary waves cylinders force behaviors mechanism study numerical simulation
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Optimization of Oil Extraction Conditions from Watermelon Seeds by Response Surface Methodology 被引量:1
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作者 wenwen zhang Guozhu HE +2 位作者 Xifeng YIN Liming zhang Yiqing ZHUANG 《Agricultural Biotechnology》 CAS 2014年第6期14-18,23,共6页
Response surface methodology was used to optimize the extraction conditions of oil from watermelon seeds. Based on single factor experiments, the material to liquid ratio, extraction time and extraction solvent exhibi... Response surface methodology was used to optimize the extraction conditions of oil from watermelon seeds. Based on single factor experiments, the material to liquid ratio, extraction time and extraction solvent exhibited the highest effects on oil extraction. The mathematical model was established according to the Box-Behnken central composite design. The optimal extraction conditions consisted of a material to liquid ratio of 1:16.3 (g/ml), an extraction time of 45.4 min, and petroleum ether as the organic solvent. The predicted and actual yields of watermelon seed oil were 27.92% and 28.04%, respectively. The extracted oil was analyzed by GC-MS. The results revealed that watermelon seed oil contained several types of acids and esters ; the relative percentages of the components were determined by a normalization method. The main fatty acids included linoleic acid, palmitic acid, oleic acid, and stearic acid, which accounted for 91.24% of the total components. 展开更多
关键词 Watermelon seed oil Response surface methodology EXTRACTION GC-MS
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A Study on the Development of Leisure Agriculture in Liaoning Province 被引量:1
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作者 wenwen zhang Erdong CHEN Yingjie HAO 《Asian Agricultural Research》 2016年第3期36-38,共3页
Leisure agriculture in foreign countries has a long history of over 100 years,and China's leisure agriculture started in the 1980 s.With the earlier reform and opening up,Shenzhen first opened " Lychee Festiv... Leisure agriculture in foreign countries has a long history of over 100 years,and China's leisure agriculture started in the 1980 s.With the earlier reform and opening up,Shenzhen first opened " Lychee Festival" in the macroscopic background,and leisure agriculture in Liaoning Province was also developed by leaps and bounds. This paper describes the basic situation of leisure agriculture in Liaoning Province,analyzes the three stages of leisure agriculture in Liaoning Province,and expounds the leisure agriculture in Liaoning's product development mode. Finally,it puts forward strategies for the development of leisure agriculture in Liaoning Province,in order to contribute to the development of leisure agriculture in Liaoning Province. 展开更多
关键词 LIAONING PROVINCE LEISURE AGRICULTURE Development
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Synthesis of an IMF zeolite membrane for the separation of xylene isomer
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作者 wenwen zhang Zhigang Xue +4 位作者 Liyun Cui Haoliang Gao Di Zhao Rongfei Zhou Weihong Xing 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第8期205-211,共7页
The synthesis of a continuous IMF zeolite membrane was fabricated on tubular substrates by seeded growth for the first time. The straight channels of IMF zeolite with diameters of 0.53–0.59 nm are distinguishable for... The synthesis of a continuous IMF zeolite membrane was fabricated on tubular substrates by seeded growth for the first time. The straight channels of IMF zeolite with diameters of 0.53–0.59 nm are distinguishable for p-xylene from o-xylene molecules. Pure IMF-phase high-silica IM-5 zeolite seeds with uniform and fine crystal size were fabricated by a new sonication-assisted aging process. The seeds were coated on the support by dipcoating and induced the formation of continuous membrane. Separation performance in p-/o-xylene mixture was investigated at various temperature and pressure. The typical IM-5zeolite membrane had p-/o-xylene separation factor of 3.7. Our results suggest that IM-5 zeolite is a potentially good membrane material for the separation of xylene mixtures. 展开更多
关键词 Membranes Zeolites SEPARATION XYLENE Secondary growth
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Application of sequential extraction for analyzing source and sink of uranium in Huanghe River sediments,China
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作者 Xihuang ZHONG Xueyan JIANG +3 位作者 Huijun HE wenwen zhang Chunxia MENG Feng SUN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期936-946,共11页
Geochemical behaviors of heavy metals are closely related to their chemical state that can be divided by sequential extraction into exchangeable(F1),bound to carbonates(F2),bound to Fe-Mn oxides(F3),bound to organic m... Geochemical behaviors of heavy metals are closely related to their chemical state that can be divided by sequential extraction into exchangeable(F1),bound to carbonates(F2),bound to Fe-Mn oxides(F3),bound to organic matter or sulfide(F4),and residual(F5).Uranium in sediment of the Huanghe(Yellow)River,China,in different chemical states was extracted using the five-step procedure of Tessier and the source and sink were analyzed.Results show that more than 70%of the total uranium was immobile residual F5 in abundance,followed in order of F4>F3>F2>F1,indicating that the main source of uranium in the sediments was from weathered rock in the drainage basin.In addition,the uranium in the sediments presents potential exogenous input in the Lanzhou,Baotou,and Tongguan reach.Fe-Mn oxides are main carriers of unstable uranium,especially those of F1 and F3.Calcite and illite are secondary adsorption minerals of unstable uranium in sediments under natural conditions.Human activities can also produce an obvious impact on uranium speciation.This study provides a reference for the application of sequential extraction in analyzing the source and sink of uranium in river sediments. 展开更多
关键词 URANIUM sequential extraction mineral composition SEDIMENT Huanghe(Yellow)River
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Effects of soil fauna on leaf litter decomposition under different land uses in eastern coast of China
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作者 Baoling Yang wenwen zhang +5 位作者 Hanmei Xu Shaojun Wang Xia Xu Huan Fan Han Y. H. Chen Honghua Ruan 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第4期968-977,共10页
Soil fauna decompose litter, whereas land use changes may significantly alter the composition and structure of soil fauna assemblages. However, little is known of the effects of land-use on the contribution of soil fa... Soil fauna decompose litter, whereas land use changes may significantly alter the composition and structure of soil fauna assemblages. However, little is known of the effects of land-use on the contribution of soil fauna to litter decomposition. We studied the impacts of soil fauna on the decomposition of litter from poplar trees under three different land uses (i.e. poplar-crop integrated system, poplar plantation, and cropland), from December 2013 to December 2014, in a coastal area of Northern Jiangsu Province. We collected litter samples in litterbags with three mesh sizes (5, 1 and 0. 01 mm, respectively) to quantify the contribution of various soil fauna to the decomposition of poplar leaf litter. Litter decomposition rates differed significantly by land use and were highest in the cropland, intermediate in the poplar-crop integrated system, and lowest in the poplar plantation. Soil fauna in the poplar-crop integrated system was characterized by the highest numbers of taxa and individuals, and highest Margalef's diversity, which suggested that agro-forestry ecosystems may support a greater quantity, distribution, and biodiversity of soil fauna than can single-species agriculture or plantation forestry. The individuals and groups of soil fauna in the macro-mesh litterbags were higher than in the meso-mesh litterbags underthe same land use types. The average contribution rate of meso- and micro-fauna to litter decomposition was 18.46%, which was higher than the contribution rate of macro-fauna (3.31%). The percentage of remaining litter mass was inversely related to the density of the soil fauna (P 〈 0.05) in poplar plantations; however, was unrelated in the poplar-crop integrated system and cropland. This may have been the result of anthropogenic interference in poplar-crop integrated systems and croplands. Our study suggested that when land-use change alters vegetation types, it can affect species composition and the structure of soil fauna assemblages, which, in turn, affects litter decomposition. 展开更多
关键词 Mesh sizes POPLAR Leaf litter Soil fauna Litter decomposition
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