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Epidemiological and clinical characteristics of COVID-19 patients in Hengyang,Hunan Province,China 被引量:3
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作者 Zhe-Feng Zhong Jia huang +19 位作者 Xia yang Jin-Ling Peng Xiao-Yan Zhang yang hu Nian Fu Hai-Lian Lin Bo Jiang Ya-Ying Tian Hong-Yi Yao Li-Pu Deng Xiao-Qing Tang Jie-Can Zhou Jian Tang Xia Xie Qiong Liu Jing Liu Cheng-Yun Dou Rong-Juan Dai Bo Yan Xue-Feng yang 《World Journal of Clinical Cases》 SCIE 2020年第12期2554-2565,共12页
BACKGROUND In December 2019,an ongoing outbreak of coronavirus disease 2019(COVID-19)was first identified in Wuhan,China.The characteristics of COVID-19 patients treated in local hospitals in Wuhan are not fully repre... BACKGROUND In December 2019,an ongoing outbreak of coronavirus disease 2019(COVID-19)was first identified in Wuhan,China.The characteristics of COVID-19 patients treated in local hospitals in Wuhan are not fully representative of patients outside Wuhan.Therefore,it is highly essential to analyze the epidemiological and clinical characteristics of COVID-19 in areas outside Wuhan or Hubei Province.To date,a limited number of studies have concentrated on the epidemiological and clinical characteristics of COVID-19 patients with different genders,clinical classification,and with or without basic diseases.AIM To study the epidemiological and clinical characteristics of COVID-19 patients in Hengyang(China)and provide a reliable reference for the prevention and control of COVID-19.METHODS From January 16 to March 2,2020,a total of 48 confirmed cases of COVID-19 were reported in Hengyang,and those cases were included in this study.The diagnostic criteria,clinical classification,and discharge standard related to COVID-19 were in line with the Diagnosis and Treatment Protocol for Novel Coronavirus Pneumonia(Trial Version 7)released by National Health Commission and National Administration of Traditional Chinese Medicine.The presence of SARS-CoV-2 in pharyngeal swab specimens was detected by quantitative reverse transcription polymerase chain reaction.All the data were imported into the excel worksheet and statistically analyzed by using SPSS 25.0 software.RESULTS A total of 48 cases of COVID-19 were collected,of which 1 was mild,38 were moderate,and 9 were severe.It was unveiled that there were 31(64.6%)male patients and 17(35.4%)female patients,with a female-to-male ratio of 1.82:1.The range of age of patients with COVID-19 was dominantly 30-49 years old[25(52.1%)of 48],followed by those aged over 60 years old[11(22.9%)].Besides,29.2%(14 of 48)of patients had basic diseases,and 57.2%(8 of 14)of patients with basic diseases were aged over 60 years old.The occupations of 48 COVID-19 patients were mainly farmers working in agricultural production[15(31.5%)of 48],rural migrant workers from Hengyang to Wuhan[15(31.5%)],and service workers operating in the service sector[8(16.7%)].The mean latent period was 6.86±3.57 d,and the median was 7[interquartile range(IQR):4-9]d.The mean time from onset of symptoms to the first physician visit was 3.38±2.98(95%CI:2.58-9.18)d,with a median of 2(IQR:1-5)d,and the mean time from hospital admission to confirmed diagnosis was 2.29±2.11(95%CI:1.18-6.42)d,with a median of 2(IQR:1-3)d.The main symptoms were fever[43(89.6%)of 48],cough and expectoration[41(85.4%)],fatigue[22(45.8%)],and chills[22(45.8%)].Other symptoms included poor appetite[13(27.1%)],sore throat[9(18.8%)],dyspnea[9(18.8%)],diarrhea[7(14.6%)],dizziness[5(10.4%)],headache[5(10.4%)],muscle pain[5(10.4%)],nausea and vomiting[4(8.3%)],hemoptysis[4(8.3%)],and runny nose[1(2.1%)].The numbers of peripheral blood leukocytes,lymphocytes,and eosinophils were significantly reduced in the majority of the patients.The levels of C-reactive protein,fibrinogen,blood glucose,lactate dehydrogenase,Ddimer,alanine aminotransferase(ALT),aspartate aminotransferase(AST),gamma-glutamyl transferase(γ-GT),myoglobin(MB),and creatine kinase(CK)were increased in 64.6%,44.7%,43.2%,37.0%,29.5%,22.9%,20.8%,21.6%,13.6%,and 12.8%of patients,respectively.The incidence of ALT elevation in male patients was remarkably higher than that in females(P<0.01),while the incidences of AST,CK,and blood glucose elevations in severe patients were remarkably higher than those in moderate patients(P<0.05,respectively).Except for the mild patients,chest computed tomography showed characteristic pulmonary lesions.All the patients received antiviral drugs,38(79.2%)accepted traditional Chinese medicine,and 2(4.2%)received treatment of human umbilical-cord mesenchymal stem cells.On March 2,2020,48 patients with COVID-19 were all cured and discharged.CONCLUSION Based on our results,patients with COVID-19 often have multiple organ dysfunction or damage.The incidences of ALT elevation in males,and AST,CK,and blood glucose elevations in severe patients are remarkably higher. 展开更多
关键词 Novel coronavirus pneumonia COVID-19 SARS-CoV-2 EPIDEMIOLOGY Hengyang Coronavirus disease 2019
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丰产优质耐贮番木瓜新品种贮丰的选育
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作者 魏岳荣 杨敏 +6 位作者 吴夏明 徐泽 邝瑞彬 杨护 贺涵 刘传和 周陈平 《果树学报》 北大核心 2026年第4期1020-1023,共4页
贮丰是通过人工杂交(GZ2013005×GZ2014002)和F1单株优选培育的丰产、优质、耐贮番木瓜新品种。该品种植株生长势中等,平均株高237.0 cm,茎粗44.6 cm,叶长79.8 cm,叶宽92.8 cm,叶柄长97.9 cm,叶柄粗(基部周长)11.1 cm。花量多,花瓣... 贮丰是通过人工杂交(GZ2013005×GZ2014002)和F1单株优选培育的丰产、优质、耐贮番木瓜新品种。该品种植株生长势中等,平均株高237.0 cm,茎粗44.6 cm,叶长79.8 cm,叶宽92.8 cm,叶柄长97.9 cm,叶柄粗(基部周长)11.1 cm。花量多,花瓣白色,连续结果能力强,丰产性强。果实椭圆形,平均单果质量916.0 g,纵径20.5 cm,横径11.2 cm,纵横径比1.83。果肉橙红色,风味清香无异味,品质优良,可溶性固形物含量(w,后同)12.6%,还原糖含量106 g·kg^(-1),总酸含量1.42 g·kg^(-1),维生素C含量1.09 g·kg^(-1),粗纤维含量0.7%。果实较耐贮,常温条件下贮藏期可达11 d。在珠江三角洲地区,按株行距2.0 m×2.5 m在春季定植时,始花期约59 d,最低结果部位高度37.8 cm,平均单株商品果数64.5个,当年平均株产59.1 kg,每666.7 m^(2)产量7092 kg。该品种适应性较强,适宜在中国广东、广西、海南、云南、福建等番木瓜产区种植,但易感番木瓜环斑花叶病毒病(papaya ringspot virus,PRSV),需重点防控,建议采用轮作方式。 展开更多
关键词 番木瓜 新品种 贮丰 丰产 耐贮
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结肠回盲部原发性黏膜黑色素瘤1例报告并文献复习
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作者 林伶 阿迪力·艾尼瓦尔 +3 位作者 张薇薇 沙拉木·克热木 杨虎 陈国栋 《中国普通外科杂志》 北大核心 2026年第1期187-191,共5页
背景与目的:原发性结肠黏膜黑色素瘤极为罕见,恶性程度高,易发生淋巴及远处转移,预后不佳,临床诊断困难。本文报告1例结肠回盲部原发性黏膜黑色素瘤病例,并结合文献复习,总结其临床特征、诊断要点、治疗策略及预后情况,以提高对该罕见... 背景与目的:原发性结肠黏膜黑色素瘤极为罕见,恶性程度高,易发生淋巴及远处转移,预后不佳,临床诊断困难。本文报告1例结肠回盲部原发性黏膜黑色素瘤病例,并结合文献复习,总结其临床特征、诊断要点、治疗策略及预后情况,以提高对该罕见疾病的认识。方法:回顾性分析1例经手术及病理证实的结肠回盲部原发性黏膜黑色素瘤患者的临床资料,包括临床表现、影像学及内镜特征、病理与免疫组化结果、分子检测结果、治疗经过及随访情况,并结合相关文献进行综合分析。结果:患者为52岁女性,2023年11月7日因“间断性右下腹痛3个月”入院。腹部增强CT提示回盲部占位并周围淋巴结肿大;肠镜见巨大结节状肿物充满肠腔,活检提示恶性黑色素瘤。行右半结肠切除术(D_(2))。术后病理示肿瘤侵犯黏膜层及深肌层,伴脉管内瘤栓,淋巴结转移5/20。免疫组化示S-100、SOX10、Melan-A及HMB45阳性,Ki-67约50%。基因检测提示BRAF^(V600E)突变。术后患者拒绝辅助治疗。术后16个月发现肠系膜区淋巴结转移,23个月出现颈部淋巴结转移,目前随访24个月,仍存活并持续随访。文献复习显示,该病多见于中老年女性,临床表现缺乏特异性,确诊依赖病理及免疫组化,手术切除为无远处转移患者的主要治疗方式。结论:结肠回盲部原发性黏膜黑色素瘤罕见且侵袭性强,早期诊断困难,易发生淋巴转移。确诊需排除转移性黑色素瘤并结合免疫组化及分子检测结果。对于无远处转移患者,根治性手术切除是首选治疗方式,分子靶向治疗及免疫治疗可能成为改善预后的重要方向。 展开更多
关键词 结肠肿瘤 黑色素瘤 外科手术 病例报告
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宁寿全宫陈设档考析
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作者 杨虎 《紫禁城》 2026年第3期112-125,共14页
宁寿全宫位于紫禁城内廷东路,与中路——乾清宫、坤宁宫、御花园、东西六宫,西路——慈宁宫、寿康宫、慈宁花园、寿安宫,一起构成紫禁城内廷。锡庆门内、皇极门以北的红墙所围区域称宁寿全宫,简称宁寿宫。宁寿全宫分中、东、西三路建筑... 宁寿全宫位于紫禁城内廷东路,与中路——乾清宫、坤宁宫、御花园、东西六宫,西路——慈宁宫、寿康宫、慈宁花园、寿安宫,一起构成紫禁城内廷。锡庆门内、皇极门以北的红墙所围区域称宁寿全宫,简称宁寿宫。宁寿全宫分中、东、西三路建筑群,中路皇极殿的建筑等级仿乾清宫,皇极殿后殿为宁寿宫,建筑等级仿坤宁宫。清宫档案中出现的“宁寿宫”,或特指皇极殿后殿,或泛指宁寿全宫建筑群,须加以辨析。本文“宁寿全宫”指宁寿宫建筑群,本文所引档案中的“宁寿宫”皆泛指建筑群。 展开更多
关键词 皇极殿 乾清宫 坤宁宫 宁寿宫 紫禁城
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免疫微环境调节骨再生 被引量:2
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作者 杨虎 郑宇 +3 位作者 贾承明 王通 张广飞 纪垚垚 《中国组织工程研究》 北大核心 2026年第3期701-710,共10页
背景:局部免疫微环境在骨生成过程中起着重要的调节作用,免疫系统与骨骼系统有着千丝万缕的联系。目的:从免疫细胞调节微环境、小细胞外囊泡调节免疫反应和骨生物材料诱导免疫反应3个方面促进骨再生进行系统综述,阐明骨再生过程中的免... 背景:局部免疫微环境在骨生成过程中起着重要的调节作用,免疫系统与骨骼系统有着千丝万缕的联系。目的:从免疫细胞调节微环境、小细胞外囊泡调节免疫反应和骨生物材料诱导免疫反应3个方面促进骨再生进行系统综述,阐明骨再生过程中的免疫调节机制。方法:检索PubMed数据库、中国知网、万方数据库及维普数据库中免疫微环境影响骨再生或骨组织修复的相关文献,以“骨免疫学,免疫微环境,小细胞外囊泡,骨再生,骨组织修复,生物材料,组织工程”为中文检索词,以“Osteoimmunology,Immune Microenvironment,Small Extracellular Vesicles,Bone Regeneration,Bone Tissue Repair,Biomaterials,Tissue Engineering”为英文检索词,删除重复和与研究目的无关文献,最后筛选出符合标准的92篇文献进行精读和综述。结果与结论:多种免疫细胞和骨细胞处于同一微环境,免疫细胞能够调控骨细胞的分化和活性,共同组成影响骨再生的免疫微环境。中性粒细胞在骨损伤初期能够显著降低局部炎症反应,为骨再生形成有利的微环境。M1型巨噬细胞能够清除异物和降低早期炎症反应,M2型巨噬细胞能够促进成骨标志物和因子的表达,共同在骨损伤的修复过程中发挥重要作用。B细胞和T细胞可直接或间接影响成骨细胞和破骨细胞的生成和活性,调节骨代谢,促进骨再生。小细胞外囊泡以旁分泌方式调节局部免疫微环境,促进骨损伤部位的骨生成和血管生成。生物材料表面的金属离子、表面亲水性、孔隙度、孔径、表面形态和表面粗糙度均能直接调节局部免疫反应,具有抗炎、促进血管生成和成骨的作用,从而加速骨再生。 展开更多
关键词 免疫微环境 骨再生 骨免疫学 骨组织工程 巨噬细胞 小细胞外囊泡 生物材料
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强省会核心区新质生产力与都市圈科创资源联动辐射路径研究——基于兰州市城关区的实践探索
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作者 高海瑞 杨虎 任莉萍 《甘肃科技纵横》 2026年第1期63-73,共11页
在强省会深入实施背景下,核心城区作为都市圈资源集聚与辐射扩散的关键枢纽,其新质生产力发展与科创资源联动水平直接影响都市圈整体高质量发展效能。文章以兰州市城关区为研究对象,基于2018—2023年城关区及兰州都市圈其他区县面板数据... 在强省会深入实施背景下,核心城区作为都市圈资源集聚与辐射扩散的关键枢纽,其新质生产力发展与科创资源联动水平直接影响都市圈整体高质量发展效能。文章以兰州市城关区为研究对象,基于2018—2023年城关区及兰州都市圈其他区县面板数据,运用熵值法、Dagum基尼系数、核密度估计、探索性空间数据分析、马尔可夫模型及障碍度模型等研究方法,系统测算城关区新质生产力发展水平,剖析其与兰州都市圈科创资源联动的区域差异、时空演化特征、空间关联效应及动态演进规律,结合西部省会城市核心城区对比明确城关区科创定位,识别联动发展的核心障碍因子,最终构建“核心集聚-圈层辐射-通道联动-机制保障”的辐射带动路径,为强省会核心区引领都市圈新质生产力协同发展提供理论支撑与实践参考。 展开更多
关键词 强省会 城关区 新质生产力 科创资源联动 辐射带动路径
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Boosting photovoltaic efficiency via efficient passive cooling from all-natural hydrogels with robust interfacial adhesion
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作者 yang Ding Xianrong huang +6 位作者 yang hu Xiangyu Zhao Gangchen Lu Cheng Zhou Shilong Liu Xiang Lu Jinping Qu 《Journal of Energy Chemistry》 2026年第3期206-216,共11页
The operational temperature rise of photovoltaic(PV)panels reduces their power generation efficiency and shortens their lifespan.Hygroscopic hydrogel-based evaporative cooling technology provides a promising solution ... The operational temperature rise of photovoltaic(PV)panels reduces their power generation efficiency and shortens their lifespan.Hygroscopic hydrogel-based evaporative cooling technology provides a promising solution for PV cooling due to high-enthalpy water evaporation.However,current hydrogels remain plagued by cooling interface mismatch and environmental concerns,which limit their practical implementation.Herein,a“green”and self-adhesive hygroscopic hydrogel consisting only of cheap lotus root powder and LiCl is designed,which can form robust interfacial adhesion with PV panels for efficient and durable cooling.Leveraging its compelling hygroscopicity,the hydrogel is able to rapidly capture moisture to recover cooling capacity,thus achieving self-sustained cooling.Besides,the“salting-in”effect brought by LiCl endows the hydrogel with notable softness and self-adhesiveness,which enables it to tightly combine with PV panels to optimize heat conduction and improve cooling efficiency.As a result,under 1.0 kW m^(-2)illumination,a PV temperature drop of 18.2℃ and a cooling power of 358 W m^(-2)were delivered by attaching the hydrogel to the rear of the PV panel,accompanied by a 7.7%improvement in energy efficiency.Overall,this self-sustained passive cooling strategy,activated by the all-natural hydrogel,sheds light on the development of PV thermal management. 展开更多
关键词 Evaporative cooling PV module thermal management Hygroscopic hydrogel Interfacial adhesion Thermal conduction
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Enhancing the electroactivity of supercapacitors through nitrogen doping on cellulose-derived carbon materials
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作者 Siling Chen yang hu +6 位作者 Sijia Zhang Xuesong Liu Zhuqun Shi Chuanxi Xiong Weiwei Wu Ruizhi Ning Quanling yang 《Chinese Chemical Letters》 2026年第2期673-677,共5页
Nowadays,higher requirements are put forward to the storage and utilization of energy,and supercapacitor is a kind of energy storage electronic devices.The resulting CA-N,with a specific surface area of 320.6 m^(2)/g ... Nowadays,higher requirements are put forward to the storage and utilization of energy,and supercapacitor is a kind of energy storage electronic devices.The resulting CA-N,with a specific surface area of 320.6 m^(2)/g and a pore volume of 0.28 cm^(3)/g,demonstrated a remarkable supercapacitance of 283.3 F/g.As a mesoporous material,CA-N offers numerous channels for the diffusion and absorption of electrolyte ions.Furthermore,it exhibited an impressive capacity retention rate of 98.48% after 5000 charge-discharge cycles.These outstanding electrochemical properties highlight the potential of CA-N for applications in energy storage. 展开更多
关键词 N-DOPED Carbon aerogel NANOCELLULOSE Porous structure SUPERCAPACITORS
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Upregulation of kazrin F by miR-186 suppresses apoptosis but promotes epithelial-mesenchymal transition to contribute to malignancy in human cervical cancer cells 被引量:6
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作者 Chang Liu Jinghua Wang +3 位作者 yang hu Hong Xie Min Liu hua Tang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2017年第1期45-56,共12页
Objective:Previous studies have identified that kazrin is a constituent of desmosome and influences intercellular adhesion,growing development and morphology.We previously cloned another new isoform,kazrin F and foun... Objective:Previous studies have identified that kazrin is a constituent of desmosome and influences intercellular adhesion,growing development and morphology.We previously cloned another new isoform,kazrin F and found that it has anti-apoptotic effects on human glioma cell line.To further explore whether kazrin F is involved in tumorigenesis,we investigated its expression and role in cervical cancer(CC) cells.Methods:The role of kazrin F and miR-186 in CC was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay,colony formation,transwell,and apoptosis assays.Using enhanced green fluorescent protein(EGFP) reporter assays,reverse transcription-quantitative polymerase chain reaction(RT-qPCR) and western blot analysis,we identified kazrin F post-transcriptional regulation by miR-186.Results:We demonstrate that kazrin F is highly expressed in CC tissues compared with the adjacent noncancerous tissues and promotes cell proliferation,colony formation,migration and invasion in HeLa and C33 A cells by suppressing apoptosis and facilitating epithelial-to-mesenchymal transition(EMT).Furthermore,miR-186 was confirmed as a regulator of kazrin F dysregulation.An EGFP reporter assay proved that miR-186 directly targets the 3'-untranslated region(3'UTR) of kazrin F and downregulates its expression,and miR-186 expression showed an inverse correlation with kazrin F levels in CC tissues.In addition,overexpression of miR-186 suppressed the malignant behaviors of CC cells.The ectopic expression of kazrin F rescued the inhibitory effects of miR-186.Conclusions:Our findings indicate that the upregulation of kazrin F due to downregulated miR-186 levels contributes to malignancy,and highlight the significance of kazrin F in CC tumorigenesis. 展开更多
关键词 Kazrin F miR-186 APOPTOSIS EMT cervical cancer
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Forest height mapping using inventory and multi-source satellite data over Hunan Province in southern China 被引量:5
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作者 Wenli huang Wankun Min +4 位作者 Jiaqi Ding Yingchun Liu yang hu Wenjian Ni huanfeng Shen 《Forest Ecosystems》 SCIE CSCD 2022年第1期57-70,共14页
Background:Accurate mapping of forest canopy heights at a fine spatial resolution over large geographical areas is challenging.It is essential for the estimation of forest aboveground biomass and the evaluation of for... Background:Accurate mapping of forest canopy heights at a fine spatial resolution over large geographical areas is challenging.It is essential for the estimation of forest aboveground biomass and the evaluation of forest ecosystems.Yet current regional to national scale forest height maps were mainly produced at coarse-scale.Such maps lack spatial details for decision-making at local scales.Recent advances in remote sensing provide great opportunities to fill this gap.Method:In this study,we evaluated the utility of multi-source satellite data for mapping forest heights over Hunan Province in China.A total of 523 plot data collected from 2017 to 2018 were utilized for calibration and validation of forest height models.Specifically,the relationships between three types of in-situ measured tree heights(maximum-,averaged-,and basal area-weighted-tree heights)and plot-level remote sensing metrics(multispectral,radar,and topo variables from Landsat,Sentinel-1/PALSAR-2,and SRTM)were analyzed.Three types of models(multilinear regression,random forest,and support vector regression)were evaluated.Feature variables were selected by two types of variable selection approaches(stepwise regression and random forest).Model parameters and model performances for different models were tuned and evaluated via a 10-fold cross-validation approach.Then,tuned models were applied to generate wall-to-wall forest height maps for Hunan Province.Results:The best estimation of plot-level tree heights(R2 ranged from 0.47 to 0.52,RMSE ranged from 3.8 to 5.3 m,and rRMSE ranged from 28%to 31%)was achieved using the random forest model.A comparison with existing forest height maps showed similar estimates of mean height,however,the ranges varied under different definitions of forest and types of tree height.Conclusions:Primary results indicate that there are small biases in estimated heights at the province scale.This study provides a framework toward establishing regional to national scale maps of vertical forest structure. 展开更多
关键词 Forest canopy height Hunan province Landsat ARD PALSAR-2 Sentinel-1
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A telomere-to-telomere genome assembly of Zhonghuang 13,a widely-grown soybean variety from the original center of Glycine max 被引量:3
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作者 Anqi Zhang Tangchao Kong +21 位作者 Baiquan Sun Shizheng Qiu Jiahe Guo Shuyong Ruan Yu Guo Jirui Guo Zhishuai Zhang Yue Liu Zheng hu Tao Jiang Yadong Liu Shuqi Cao Shi Sun Tingting Wu huilong Hong Bingjun Jiang Maoxiang yang Xiangyu Yao yang hu Bo Liu Tianfu Han Yadong Wang 《The Crop Journal》 SCIE CSCD 2024年第1期142-153,共12页
Soybean(Glycine max)stands as a globally significant agricultural crop,and the comprehensive assembly of its genome is of paramount importance for unraveling its biological characteristics and evolutionary history.Nev... Soybean(Glycine max)stands as a globally significant agricultural crop,and the comprehensive assembly of its genome is of paramount importance for unraveling its biological characteristics and evolutionary history.Nevertheless,previous soybean genome assemblies have harbored gaps and incompleteness,which have constrained in-depth investigations into soybean.Here,we present Telomere-to-Telomere(T2T)assembly of the Chinese soybean cultivar Zhonghuang 13(ZH13)genome,termed ZH13-T2T,utilizing PacBio Hifi and ONT ultralong reads.We employed a multi-assembler approach,integrating Hifiasm,NextDenovo,and Canu,to minimize biases and enhance assembly accuracy.The assembly spans 1,015,024,879 bp,effectively resolving all 393 gaps that previously plagued the reference genome.Our annotation efforts identified 50,564 high-confidence protein-coding genes,707 of which are novel.ZH13-T2T revealed longer chromosomes,421 not-aligned regions(NARs),112 structure variations(SVs),and a substantial expansion of repetitive element compared to earlier assemblies.Specifically,we identified 25.67 Mb of tandem repeats,an enrichment of 5S and 48S rDNAs,and characterized their genotypic diversity.In summary,we deliver the first complete Chinese soybean cultivar T2T genome.The comprehensive annotation,along with precise centromere and telomere characterization,as well as insights into structural variations,further enhance our understanding of soybean genetics and evolution. 展开更多
关键词 SOYBEAN Telomere-to-Telomere assembly Zhonghuang 13 Structure variations
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A Discussion on the Characteristics of Tectonic Transformation and Its Mechanism of 2nd Episode of Zhu-Qiong Movement in Zhu 1 Depression, South China 被引量:1
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作者 yang hu 《Journal of Geoscience and Environment Protection》 2021年第1期1-12,共12页
<div style="text-align:justify;"> Based on the detailed interpretation of high-accuracy 3D seismic data, the characteristics of regional unconformities, fracture systems, sedimentary filling and paleo-... <div style="text-align:justify;"> Based on the detailed interpretation of high-accuracy 3D seismic data, the characteristics of regional unconformities, fracture systems, sedimentary filling and paleo-stress field in Zhu 1 depression were comprehensively analyzed. The results showed that 2nd episode of Zhu-Qiong movement was an important tectonic transformation that occurred during rifting, basin structure patterns above and below the regional angular unconformity caused by 2nd episode had distinct differences. The orientations of those basin-controlling faults changed from NE, NEE to EW, NWW, which indicated that the paleo-stress field veered from NNW extension clockwise to sub-NS extension and basin structures patterns transformed from NE, NEE strong rifting to sub-EW, NWW weak rifting. The depocenter showed seesaw-like migration from S to N. And the sedimentary systems transformed from semi-deep-deep lacustrine facies to braided river delta facies developed in shore-shallow lacustrine. Combined with its tectonic recombination of periphery plates that period, the mechanism of above tectonic transformation had direct correspondence to the readjustment of the Indian plate and the Pacific plate. The southward subduction of the pro-to-south China Sea is the direct cause of this tectonic transformation. </div> 展开更多
关键词 Tectonic Transformation Genetic Mechanism 2nd Episode of Zhu-Qiong Movement Zhu 1 Depression
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O_(2)/CO_(2)气氛下回转窑煤粉燃烧及NO_(x)生成的数值模拟 被引量:1
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作者 梅书霞 李全亮 +3 位作者 杨虎 王艺 谢峻林 何峰 《新世纪水泥导报》 2025年第5期13-17,26,I0011,共7页
针对一水泥回转窑建立模型进行数值模拟,对O_(2)/N_(2)和O_(2)/CO_(2)两种气氛下回转窑内的煤粉燃烧及NO_(x)生成过程进行了对比研究,探究了回转窑O_(2)/CO_(2)气氛燃烧的可行性。模拟结果表明:改变气氛前后气流流场无明显变化,高温区... 针对一水泥回转窑建立模型进行数值模拟,对O_(2)/N_(2)和O_(2)/CO_(2)两种气氛下回转窑内的煤粉燃烧及NO_(x)生成过程进行了对比研究,探究了回转窑O_(2)/CO_(2)气氛燃烧的可行性。模拟结果表明:改变气氛前后气流流场无明显变化,高温区形状皆呈“棒槌状”;黑火头延长了约0.3m;窑内最高温度下降了298℃;前30m平均温度整体下降,壁面接收总辐射量降低5.2%;NO_(x)的生成量降低约51.32%。 展开更多
关键词 回转窑 富氧燃烧 煤粉燃烧 NO_(x)生成 数值模拟
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红糖发酵棉秆的营养品质研究及其对湖羊养分表观消化率的影响
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作者 高丽 张俊瑜 +4 位作者 巴音巴特 曾涛 阿衣江·卡克尔曼 米日扎提·艾热提 杨虎 《饲料研究》 北大核心 2025年第20期6-10,共5页
试验旨在探究不同水平红糖发酵棉秆的营养品质及棉秆微贮对湖羊养分表观消化率的影响。采用单因素试验设计,在膨化棉秆中分别添加0(CK组)、0.5%(A组)、1.0%(B组)、1.5%(C组)和2.0%(D组)红糖微贮发酵56 d,每个处理4个重复。选用体重、月... 试验旨在探究不同水平红糖发酵棉秆的营养品质及棉秆微贮对湖羊养分表观消化率的影响。采用单因素试验设计,在膨化棉秆中分别添加0(CK组)、0.5%(A组)、1.0%(B组)、1.5%(C组)和2.0%(D组)红糖微贮发酵56 d,每个处理4个重复。选用体重、月龄相近的健康湖羊30只,随机分为5组,每组6个重复,每个重复1只羊。对照组(XCK组)饲喂基础饲粮,试验组分别用10%(XA组)、20%(XB组)、30%(XC组)和40%(XD组)的棉秆微贮(添加1%红糖)替代基础饲粮。预试期7 d,正式试验期6 d。结果显示,在不同发酵期(除发酵0 d),各试验组pH值均显著或极显著低于CK组(P<0.05或P<0.01)。发酵7 d时,A组pH值极显著高于B组、C组和D组(P<0.01)。与CK组相比,D组总酸和乳酸(LA)含量分别极显著升高13.81%和24.87%(P<0.01),乙酸(AA)和丁酸(BA)含量分别极显著降低了10.48%和65.67%(P<0.01)。与CK组相比,B组棉秆微贮的中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量分别极显著降低了8.70%和13.90%(P<0.01)。D组游离棉酚(FG)含量最低,且比CK组降低了16.51%(P<0.01)。XB组湖羊对干物质(DM)、有机物(OM)、粗蛋白(CP)、NDF、ADF的表观消化率最高。研究表明,添加1.0%红糖能够提高棉秆微贮发酵品质,降低FG含量,当棉秆微贮替代20%的基础饲粮时,湖羊对饲粮的养分表观消化率较高。 展开更多
关键词 红糖 棉秆微贮 发酵品质 湖羊 养分表观消化率
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负载型离子液体制备及其对湿法磷酸提纯研究
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作者 杨虎 杨思原 +3 位作者 罗梦恒 吴晨旭 匡步肖 包申旭 《现代化工》 北大核心 2025年第7期112-118,共7页
将离子液体通过化学接枝法负载在树脂上,制备了一种能从湿法磷酸中高效选择性吸附磷的负载型离子液体,并采用FT-IR、SEM-EDS和XPS对其进行表征分析。在制备温度为95℃、时间为16 h、液固比(mL∶g)为40∶1、氨基乙酸溶液浓度为2.66 mmol/... 将离子液体通过化学接枝法负载在树脂上,制备了一种能从湿法磷酸中高效选择性吸附磷的负载型离子液体,并采用FT-IR、SEM-EDS和XPS对其进行表征分析。在制备温度为95℃、时间为16 h、液固比(mL∶g)为40∶1、氨基乙酸溶液浓度为2.66 mmol/g的条件下,制备的材料对磷的平衡吸附量达到333.1 mg/g。在选择性吸附方面,对磷的吸附量远高于杂质离子(铁、铝和镁),说明材料对磷与杂质离子有较好的分离性能。尤其是磷与镁的分离系数达到636.83。这表明此材料能够实现复杂磷酸溶液中磷与杂质离子的选择性分离,特别是在含镁量高的磷酸溶液中提纯效果显著。还通过表征分析推断该材料对磷酸吸附机理主要是络合反应与阴离子交换的协同作用。 展开更多
关键词 湿法磷酸 负载型离子液体 吸附 选择性 提纯
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数字技术能否促进营商环境优化 被引量:1
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作者 杨瑚 《生产力研究》 2025年第7期34-38,共5页
优化营商环境是实现高质量发展的关键之举。以2017—2021年中国30个省(区、市)为样本数据,采用主效应模型与面板门槛效应模型考察数字技术对营商环境的影响。研究结果表明:数字技术显著促进营商环境优化,且存在非线性影响效应;异质性分... 优化营商环境是实现高质量发展的关键之举。以2017—2021年中国30个省(区、市)为样本数据,采用主效应模型与面板门槛效应模型考察数字技术对营商环境的影响。研究结果表明:数字技术显著促进营商环境优化,且存在非线性影响效应;异质性分析结果发现,东部和中部地区的数字技术对营商环境具有显著的正向影响,而西部地区的数字技术对营商环境有正向影响,但不显著;数字技术对营商环境的人文环境与市场环境的作用强度高于法治环境,对政务环境的影响不显著。研究结论为进一步加深数字技术应用,优化我国营商环境提供经验证据。 展开更多
关键词 数字技术 营商环境 高质量发展
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面向中医药高维小样本的多组学数据融合方法初探 被引量:4
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作者 王念 俞成诚 +2 位作者 杨虎 王忠 刘骏 《中国中药杂志》 北大核心 2025年第1期278-284,共7页
随着大数据和人工智能技术的发展,组学技术在中医药研究中的广泛应用生成了大型实验数据集,跨尺度寻找海量数据之间的关联成为可能,由此也逐步进入数据密集型研究范式。重视技术及算力工具的多组学数据融合分析模式作为新兴方法之一,或... 随着大数据和人工智能技术的发展,组学技术在中医药研究中的广泛应用生成了大型实验数据集,跨尺度寻找海量数据之间的关联成为可能,由此也逐步进入数据密集型研究范式。重视技术及算力工具的多组学数据融合分析模式作为新兴方法之一,或许是该领域的突破点。中医学的整体观念与多组学数据融合的理念呈现相似之处,但其数据类型呈现高维小样本特征,因此需要通过降维等的方式对数据进行处理。目前的挑战是如何选择适合数据的分析方法,增加对生理功能和疾病诊疗过程的系统理解。因此该文通过对多组学数据融合的理论和框架进行探索,分析中医药高维小样本多组学数据融合的方法,拟为中医药的发展提供思路。 展开更多
关键词 多组学 中医药 数据融合 高维小样本
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民族地区旅游发展与乡村可持续发展的耦合协调研究
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作者 杨瑚 蔡雪玲 《陇东学院学报》 2025年第1期78-83,共6页
旅游业与乡村可持续发展的耦合协调发展是推动民族地区发展的重要举措。以2010—2020年民族地区为研究对象,借助熵权法、TOPSIS评价模型和耦合协调模型研究民族地区旅游发展与乡村可持续发展耦合协调度,并基于Dagum基尼系数、Kernel估计... 旅游业与乡村可持续发展的耦合协调发展是推动民族地区发展的重要举措。以2010—2020年民族地区为研究对象,借助熵权法、TOPSIS评价模型和耦合协调模型研究民族地区旅游发展与乡村可持续发展耦合协调度,并基于Dagum基尼系数、Kernel估计和Tobit模型探究其时空演化特征与影响因素。研究结果表明:民族地区旅游发展与乡村可持续发展的耦合协调度稳步增长,呈现出由勉强协调至初级协调的演变特征;民族地区旅游发展与乡村可持续发展耦合协调度的区域内差异呈现西北高,西南低的特征,总体差距逐渐缩小;经济发展、投资力度、产业结构优化和政策支持显著驱动民族地区旅游发展与乡村可持续发展的耦合协调。 展开更多
关键词 旅游发展 乡村可持续发展 耦合协调 民族地区
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基于客源信息的地铁客流控制模型 被引量:3
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作者 吕思锐 阳虎 王璞 《铁道科学与工程学报》 北大核心 2025年第4期1530-1541,共12页
随着乘客出行需求的快速增长,地铁高峰时段拥挤现象越来越严重。为了缓解地铁客流拥挤,提出了基于客源信息的地铁客流控制模型。首先,利用智能卡刷卡数据识别地铁网络拥挤区间,并定位经过这些区间的乘客的上车站点(客源);接着,利用K-me... 随着乘客出行需求的快速增长,地铁高峰时段拥挤现象越来越严重。为了缓解地铁客流拥挤,提出了基于客源信息的地铁客流控制模型。首先,利用智能卡刷卡数据识别地铁网络拥挤区间,并定位经过这些区间的乘客的上车站点(客源);接着,利用K-means聚类算法对客源进行聚类,将其中客流贡献量最大的一类客源定义为主要客源;然后,将主要客源站点作为候选客流控制站点,以最小化乘客总等待时间为目标,并引入列车容量约束、乘客等待时间约束和客流约束,构建客流控制模型;最后,应用遗传算法求解客流控制方案,方案包括:控制站点、控制时间窗和客流控制率。以2016年8月的深圳地铁为对象进行实证分析,结果表明,所构建模型生成的多站协同的客流控制方案能够有效缓解深圳地铁客流早高峰拥挤。通过对比延误乘客人数、总等待时间、平均上车率和控制站点总数这4个评价指标,发现基于客源信息的客流控制模型综合性能最优。基于客源信息的客流控制模型能够应用于大规模地铁网络,有效缓解客流拥挤,减少延误乘客数量,保障站点上车率。此外,研究结果表明,地铁拥挤区间的大部分乘客来源于少数站点,在这些站点实施客流控制能够更加高效地缓解地铁客流拥挤。 展开更多
关键词 拥挤区间 客源 客流控制 延误乘客 等待时间 拥挤缓解
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辽河口不同退塘还湿方式对大型底栖动物的影响
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作者 宋远昊 龚吕 +2 位作者 李贲 胡阳 李秀珍 《生物多样性》 北大核心 2025年第2期89-101,共13页
“自然湿地-围塘养殖-退塘还湿”是海岸带生态保护修复背景下很多湿地面临的土地利用类型转变模式,但不同退塘还湿方式实施后的恢复情况及其作用机理尚不清晰。为评估2015年辽河口退塘还湿工程开展后不同退塘还湿方式的大型底栖动物恢... “自然湿地-围塘养殖-退塘还湿”是海岸带生态保护修复背景下很多湿地面临的土地利用类型转变模式,但不同退塘还湿方式实施后的恢复情况及其作用机理尚不清晰。为评估2015年辽河口退塘还湿工程开展后不同退塘还湿方式的大型底栖动物恢复情况,本研究以辽河口退塘还湿工程区内退塘程度逐步提升的未推平、半推平和全推平塘坝3种退塘样地及天然盐地碱蓬(Suaeda salsa)对照区作为调查区,分别于2023年春季和秋季对不同样地的大型底栖动物及其环境因子进行调查和分析。结果显示:鉴定到大型底栖动物21种,隶属于3门5纲16科,春季优势种为谭氏泥蟹(Ilyoplax deschampsi)、绯拟沼螺(Assiminea latericea)、小头虫(Capitella capitata)等,秋季优势种为绯拟沼螺、拟沼螺属一种(Assiminea sp.)、小头虫等。春季半推平塘坝区大型底栖动物生物量显著高于未推平和全推平塘坝区,秋季全推平塘坝区的大型底栖动物密度显著高于未推平和半推平塘坝区,生物量显著高于未推平塘坝区,均匀度指数显著低于半推平塘坝区。非度量多维尺度分析与相似性分析结果显示:春秋两季,不同退塘样地的大型底栖动物群落结构存在显著差异。生物与环境非线性回归表明,高程、沉积物温度、含水率、电导率、砂含量和总氮含量与大型底栖动物分布密切相关。本研究可为我国海岸带养殖塘的修复和管理提供基础数据与理论支撑。 展开更多
关键词 退塘还湿 生态修复 大型底栖动物 滨海湿地 环境因子
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