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巨菌草对育肥从江香猪生长性能及肠道健康的影响 被引量:3
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作者 张敏 杨锐 +7 位作者 黄逸州 林芷昕 郑贤跃 刘庆华 高玉云 林冬梅 林占熺 金灵 《草业学报》 北大核心 2025年第5期171-188,共18页
本试验旨在探究巨菌草替代不同水平基础饲粮对育肥从江香猪生长性能及肠道健康的影响。选取6月龄体重相近的健康从江香猪30头,随机分为3组(每组5个重复,每个重复2头)。对照组饲喂100%基础饲粮,试验Ⅰ、Ⅱ组分别用新鲜青绿巨菌草替代10%... 本试验旨在探究巨菌草替代不同水平基础饲粮对育肥从江香猪生长性能及肠道健康的影响。选取6月龄体重相近的健康从江香猪30头,随机分为3组(每组5个重复,每个重复2头)。对照组饲喂100%基础饲粮,试验Ⅰ、Ⅱ组分别用新鲜青绿巨菌草替代10%、20%基础饲粮,试验期90 d。通过测定育肥从江香猪生长性能、肠道发育、肠道机械屏障和盲肠菌群结构,并进行经济效益分析,为巨菌草在猪的生产应用中提供理论依据。本试验主要结果如下:1)生长性能:与对照组相比,试验Ⅰ、Ⅱ组育肥从江香猪生长性能及胴体性状各指标无显著差异(P>0.05)。巨菌草不计成本时,与对照组相比,试验Ⅰ组的增重成本降低8.73%,试验Ⅱ组降低11.59%;巨菌草按市场价格0.35元·kg^(-1)计算时,试验Ⅰ组的增重成本降低2.78%,试验Ⅱ组增加1.35%。2)肠道发育:与对照组相比,试验Ⅰ、Ⅱ组育肥从江香猪胃的相对重量显著提高(P<0.05),小肠相对重量有升高的趋势(P=0.092)。与对照组相比,试验Ⅰ组育肥从江香猪回肠隐窝深度显著降低(P<0.05),回肠绒毛高度/隐窝深度(V/C)、空肠GLP-2和回肠IGF-1R基因表达量显著提高(P<0.05);试验Ⅱ组育肥从江香猪回肠绒毛高度、V/C及空肠GLP-2基因表达量显著提高(P<0.05)。3)肠道免疫及机械屏障:与对照组相比,试验Ⅰ、Ⅱ组育肥从江香猪回肠IFN-γ含量显著降低,试验Ⅱ组空肠TGF-β含量显著提高(P<0.05);试验Ⅰ、Ⅱ组回肠ZO-1基因表达量显著提高,试验Ⅱ组空肠Occludin基因表达量显著提高(P<0.05)。4)盲肠微生物区系:与对照组相比,试验Ⅰ、Ⅱ组育肥从江香猪Shannon指数显著提高,链球菌属相对丰度显著下降(P<0.05)。试验Ⅰ组和试验Ⅱ组毛螺菌科未分类菌属有上升趋势(P=0.065),螺旋体门(P=0.085)、密螺旋体属(P=0.085)有下降趋势。综上所述,巨菌草替代部分基础饲粮对育肥从江香猪生长性能、胴体性状无显著影响,但可提高经济效益并促进胃肠道的发育,提升肠道屏障功能,有利于肠道健康。巨菌草不计成本时,替代20%基础饲粮为宜,巨菌草按市场价格0.35元·kg^(-1)计算时,替代10%基础饲粮为宜。 展开更多
关键词 巨菌草 育肥从江香猪 生长性能 盲肠菌群 肠道健康
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基于注意力机制的双卷积图像去噪网络
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作者 周先春 吕梦楠 +3 位作者 芮旸 唐彬鑫 杜志亭 陈玉泽 《电子测量与仪器学报》 北大核心 2025年第2期60-71,共12页
近年来,深度卷积神经网络在图像去噪领域表现出了优越的性能。然而,深度网络结构往往伴随着大量的模型参数,导致训练成本高,推理时间长,限制了其在实际去噪任务中的应用。提出了一种新的基于注意力机制的双卷积图像去噪网络(MA-DFRNet)... 近年来,深度卷积神经网络在图像去噪领域表现出了优越的性能。然而,深度网络结构往往伴随着大量的模型参数,导致训练成本高,推理时间长,限制了其在实际去噪任务中的应用。提出了一种新的基于注意力机制的双卷积图像去噪网络(MA-DFRNet),它由多尺度特征特征提取网络、双卷积神经网络及动态特征精炼注意力机制组成。多尺度特征提取网络通过不同尺度的卷积获取图像特征,提高灵活性。双卷积神经网络上下分支均采用跳跃连接及扩张卷积来增大感受野。动态特征精炼注意力机制增强特征表示的精度和区分能力。这种结构设计不仅扩大了感受野,还更有效地提取和融合图像特征,显著提升去噪效果。研究结果表明,与最先进的模型相比,提出的MA-DFRNet在所有对比的噪声水平下具有更高的峰值信噪比(PSNR)和结构相似性(SSIM)值,PSNR提高了0.2 dB左右,SSIM提高了1%左右,对于噪声水平较高的图像更具鲁棒性,并且在视觉上更好地保留了图像细节,实现去噪和细节保留之间的平衡。 展开更多
关键词 图像去噪 卷积神经网络 注意力机制 跳跃连接 多尺度特征提取网络
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清华大学校园鸟类多样性特征与环境关联 被引量:1
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作者 曾子轩 杨锐 +1 位作者 黄越 陈路遥 《生物多样性》 北大核心 2025年第5期21-33,共13页
城市绿地是生物多样性保护的重要载体,大学校园作为城市建成区的缩影,对提升小微绿地质量与生物多样性保护有重要意义。然而,已有大学校园生物多样性研究缺乏连续的时间与空间信息,且未明确物种与绿地内部植被结构的关联,可能影响小微... 城市绿地是生物多样性保护的重要载体,大学校园作为城市建成区的缩影,对提升小微绿地质量与生物多样性保护有重要意义。然而,已有大学校园生物多样性研究缺乏连续的时间与空间信息,且未明确物种与绿地内部植被结构的关联,可能影响小微绿地内部结构质量的优化。本文以清华大学校园鸟类为研究对象,通过实地调查鸟类与植物群落,运用广义线性模型和冗余分析,探讨了大学校园的鸟类分布时空格局以及鸟类组成与绿地特征的关联。研究发现,鸟类在大学校园绿地内部呈现集中分布且存在季节差异。鸟类组成与木本食源植物丰富度、灌木均匀度、草本盖度、人工草地盖度、乔木盖度存在关联。其中木本食源植物丰富度与鸟类多度、丰富度及Shannon多样性指数呈正向关联,灌木均匀度与鸟类丰富度及Shannon多样性指数呈正向关联,乔木盖度和人工草地盖度仅同时分别小于等于37.5%与小于39.8%时与鸟类多度呈正向关联,而草本盖度则与鸟类丰富度及Shannon多样性指数呈负向关联。此外,不同居留型鸟类的生境选择存在差异,秋季的过境鸟分布仅关联于植被结构,留鸟和冬候鸟分布同时关联于绿地物理特征和植被结构。我们建议在遵循自然规律营造城市小微绿地时,应控制乔木盖度和人工草地盖度同时在约40%以下,提升木本食源植物丰富度和灌木均匀度,并增加自然草本植物覆盖和植被结构层次。本研究面向城市小微绿地提出定量与定性结合的近自然绿地营造建议,为落实《昆明-蒙特利尔全球生物多样性框架》和《中国生物多样性保护战略与行动计划(2023–2030年)》的城市蓝绿空间质量提升目标提供了科学依据。 展开更多
关键词 生物多样性 城市小微绿地 大学校园 植被结构 保护管理
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黄河流域传统村落保护与利用水平的空间特征及其影响因素比较
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作者 孙玮鸿 芮旸 +1 位作者 谢将将 刘珂菁 《西北大学学报(自然科学版)》 北大核心 2025年第4期932-942,共11页
传统村落保护与利用的对立统一关系亟待地理学视角的探讨。以黄河流域为研究区,基于保存率与利用率指标,采用双变量空间自相关、地理探测器等方法,沿“水平评价-空间特征-空间归因”主线,对传统村落的保护与利用进行比较研究。结果表明:... 传统村落保护与利用的对立统一关系亟待地理学视角的探讨。以黄河流域为研究区,基于保存率与利用率指标,采用双变量空间自相关、地理探测器等方法,沿“水平评价-空间特征-空间归因”主线,对传统村落的保护与利用进行比较研究。结果表明:(1)黄河流域传统村落的保护相对滞后于利用,保存率与全国相近,在中游地区最高,利用率则显著高于全国,在下游地区最高;(2)该流域传统村落保存率的空间正相关性显著,但利用率不具有自相关性,两者间存在显著的全局空间负相关性,并在局域表现出低-高类和高-高类单元共同集聚在上游、高-低类和低-低类单元主要分布在下游的特征;(3)该流域传统村落的保护与利用水平都受到多维因素的共同作用,但主导因子差异明显,保护水平主要是人口、土地和经济因素的函数,利用水平主要是文化、市场和经济因素的函数。建议针对保护与利用分别施策、协同推进,整体提升黄河流域传统村落的保护与利用水平。 展开更多
关键词 传统村落 保护水平 利用水平 空间特征 影响因素
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加热器结构对轻掺磷超低氧直拉单晶硅氧杂质分布的影响
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作者 商润龙 陈亚 +4 位作者 芮阳 王黎光 马成 伊冉 杨少林 《人工晶体学报》 北大核心 2025年第5期801-808,共8页
绝缘栅双极晶体管(IGBT)是能源转换与传输的核心器件,广泛应用于轨道交通、智能电网、航空航天及电动汽车等领域。作为IGBT芯片的衬底材料,轻掺磷超低氧硅晶圆的品质对IGBT芯片的性能起着至关重要的作用。由于直拉(Czochralski, Cz)单... 绝缘栅双极晶体管(IGBT)是能源转换与传输的核心器件,广泛应用于轨道交通、智能电网、航空航天及电动汽车等领域。作为IGBT芯片的衬底材料,轻掺磷超低氧硅晶圆的品质对IGBT芯片的性能起着至关重要的作用。由于直拉(Czochralski, Cz)单晶硅拉制的过程中需要用到含氧的石英坩埚,生长的单晶硅氧含量通常达到4×10^(17)~9×10^(17)atoms/cm^(3),远高于IGBT用硅片所需的小于2.5×10^(17)atoms/cm3的氧含量需求。为解决上述问题,本文通过对应用32英寸(1英寸=2.54 cm)热场的单晶硅生长进行数值模拟,设计出新式加热器来制备满足IGBT衬底需求的超低氧单晶硅棒。模拟结果显示,当采用分体式加热器时,石英坩埚壁和固液界面附近硅熔体的流速会减弱。这一现象有助于减少熔体中的氧含量及氧杂质向固液界面的传输,进而有效降低晶棒中整体的氧含量。此外,由于采用了分体式加热器,固液界面处晶棒的轴向温度梯度相较于常规加热器显著降低,这一优势也有利于减少硅棒中的氧含量。实验结果进一步证实了模拟结果,在分体式加热器下拉制的单晶硅棒的氧含量更低,且整体保持在2.5×10^(17)atoms/cm^(3)以下,完全符合IGBT衬底的要求。 展开更多
关键词 Cz法 超低氧单晶硅 分体式加热器 氧含量
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Evaluating the effectiveness of ultrasound-assisted wound debridement in managing diabetic foot ulcers:A systematic review and meta-analysis 被引量:2
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作者 rui yang Geng Chen +5 位作者 Qing-Yun Pan Yao Yao Yan-Fen Li Hai-Ting Chen Chang-Jiang Lei Xia Liang 《World Journal of Diabetes》 2025年第2期246-256,共11页
BACKGROUND Diabetic foot ulcers(DFUs)present a significant clinical challenge due to their high prevalence and profound impact on morbidity.Ultrasound-assisted wound debridement(UAWD)has emerged as a potential therape... BACKGROUND Diabetic foot ulcers(DFUs)present a significant clinical challenge due to their high prevalence and profound impact on morbidity.Ultrasound-assisted wound debridement(UAWD)has emerged as a potential therapeutic modality to improve healing outcomes in DFU management.AIM To evaluate the efficacy of UAWD in treating DFUs on wound closure rates,treatment duration,and quality of life outcomes.METHODS This systematic review and meta-analysis followed PRISMA guidelines,systematically searching PubMed,Embase,Web of Science,and the Cochrane Library with no date restrictions.Randomized controlled trials(RCTs)that evaluated the efficacy of UAWD in DFU treatment were included.Data were independently extracted by two reviewers,with discrepancies resolved through consensus or third-party consultation.The risk of bias was assessed using the Cochrane tool.χ2 and I2 statistics assessed heterogeneity,informing the use of fixed or random-effects models for meta-analysis,supplemented by sensitivity analysis and publication bias assessment through funnel plots and Egger's test.RESULTS From 1255 articles,seven RCTs met the inclusion criteria.The studies demonstrated that UAWD significantly reduced DFU healing time(standardized mean difference=-0.78,95%CI:-0.97 to-0.60,P<0.001)and increased healing rates(odds ratio=9.96,95%CI:5.99 to 16.56,P<0.001)compared to standard care.Sensitivity analysis confirmed the stability of these results,and no significant publication bias was detected.CONCLUSION UAWD is a promising adjunctive treatment for DFUs,significantly reducing healing times and increasing healing rates.These findings advocate for the integration of UAWD into standard DFU care protocols. 展开更多
关键词 Diabetic foot ulcers Ultrasound-assisted wound debridement Healing time Healing rates META-ANALYSIS
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黄酮类生物基苯并噁嗪树脂的合成、固化机理及性能研究
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作者 胡长文 杨蕊 张侃 《高分子学报》 北大核心 2025年第8期1426-1437,共12页
本文设计并合成了一系列黄酮类生物基苯并噁嗪单体,系统研究了不同官能度黄酮类生物基苯并噁嗪分子结构与固化机理及固化后树脂材料热稳定性和阻燃性的关联机制.首先采用NMR、FTIR等表征手段确认苯并噁嗪单体的分子结构,再通过DSC和原位... 本文设计并合成了一系列黄酮类生物基苯并噁嗪单体,系统研究了不同官能度黄酮类生物基苯并噁嗪分子结构与固化机理及固化后树脂材料热稳定性和阻燃性的关联机制.首先采用NMR、FTIR等表征手段确认苯并噁嗪单体的分子结构,再通过DSC和原位FTIR谱图来研究苯并噁嗪单体的聚合过程结构演变与固化机理.该系列黄酮类苯并噁嗪中的酚羟基与其相邻羰基之间分子内氢键被确定为导致热潜伏催化固化行为的根本原因.其中,基于芹菜素双官苯并噁嗪树脂制备的热固性树脂具有极高的热稳定性(Td5为384℃),由木犀草素基三官苯并噁嗪制备的聚苯并噁嗪树脂具有最为优异的阻燃性(HRC<10 J·g^(−1)·K^(−1)).以上研究表明黄酮类生物基热固性树脂在高性能材料领域具有巨大的应用潜力. 展开更多
关键词 生物基 苯并噁嗪 高热稳定性 阻燃性 潜伏催化固化
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面向资源转化的中国传统村落分类振兴研究——基于“人-业-位”要素视角 被引量:5
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作者 芮旸 罗飞 +2 位作者 王玲 孙玮鸿 刘晓琼 《干旱区资源与环境》 CSSCI CSCD 北大核心 2024年第1期87-95,共9页
不同于一般村落,传统村落兼具社区、遗产和资源三重属性,资源属性的转化在其振兴中发挥着纽带作用。面向资源转化,选取4221个国家级传统村落为研究样本,开展传统村落分类振兴的理论和实证研究。结果表明:1)传统村落资源转化的核心要素... 不同于一般村落,传统村落兼具社区、遗产和资源三重属性,资源属性的转化在其振兴中发挥着纽带作用。面向资源转化,选取4221个国家级传统村落为研究样本,开展传统村落分类振兴的理论和实证研究。结果表明:1)传统村落资源转化的核心要素是人口、产业和区位,其中“人”是主体、“业”是基础、“位”是条件,三者缺一不可。2)传统村落按单要素的优劣性分为人口空心村与实心村、产业一般村与示范村、区位不优村与优势村,按三要素的完备性分为4类8型。3)传统村落难以村村同等、同样、同步振兴,仅1.09%的村落三要素俱全,46.88%的村落三要素俱缺;只有约5%的村落有优势主导产业,近70%的村落人口空心化,超过2/3的村落缺乏区位优势。但有要素优势的村落分布更均衡,有利于形成以点带面的振兴格局。4)传统村落根据资源转化要素类型的不同,可相应采取转化示范、人口集聚、产业提升、区位改善、人口驱动、产业带动、区位拉动、资源保护等路径分类推进乡村振兴,并分4个梯队有序实现乡村振兴。 展开更多
关键词 传统村落 分类 资源转化 乡村振兴 中国
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论建立中国自然保护兼用地的必要性和可行性 被引量:9
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作者 杨锐 侯姝彧 +1 位作者 张引 赵智聪 《生物多样性》 CAS CSCD 北大核心 2024年第4期163-178,共16页
联合国《生物多样性公约》第十五次缔约方大会(COP15)提出“30×30”目标,呼吁到2030年保护全球30%的陆地和海洋面积。目前自然保护地覆盖率不足、拓展空间有限、与其他土地类型兼容性有限,实现生物多样性全面有效保护的目标不能仅... 联合国《生物多样性公约》第十五次缔约方大会(COP15)提出“30×30”目标,呼吁到2030年保护全球30%的陆地和海洋面积。目前自然保护地覆盖率不足、拓展空间有限、与其他土地类型兼容性有限,实现生物多样性全面有效保护的目标不能仅仅依靠自然保护地。然而,国际上提倡的“其他基于区域的有效保护措施”(other effective area-based conservation measures,OECMs)尚存较多局限,与我国实际情况的适配性不足,难以直接指导我国自然保护地体系外就地保护实践。中国需要尽快建立一套与当前自然保护地相互补充的、符合中国国情的就地保护体系。基于此,本研究提出“自然保护兼用地”(conservation compatibleland,CCL)的概念——“由各类主体申请、各级政府依法确认,以保护和利用相兼容的管理方式,对高生物多样性地区进行长期、有效保护的陆域或水域”,作为我国自然保护地外的就地保护措施。本研究对CCL的内涵、定位、特征进行初步界定,并从法律政策和管理实践方面论述其可行性。未来我国的国土空间布局应包含自然保护专用地(自然保护地和生态保护红线)、CCL (兼有生物多样性保护以及农林渔牧、文化、生活等其他使用功能)以及可持续利用地(其他生产与生活用地)三大类。CCL有助于整合我国现有的自然保护地体系外的保护措施,全面系统认识自然保护地外的就地保护措施的作用,梳理经验、推广实践、整合资源、扩大影响。未来可进一步形成多层次、多梯度、保护与利用统筹协调的全域土地利用空间格局,使每一寸中国国土都兼顾保护与发展功能。本研究旨在为中国自然保护地外的就地保护实践提供理论依据,并为全球“30×30”生物多样性保护目标贡献中国智慧与中国方案。 展开更多
关键词 生态文明 国土空间规划 可持续发展 其他基于区域的有效保护措施(OECMs) 适应性管理
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Phenotypic advantages and improved genomic stability following selection in advanced selfing-generations of Brassica allohexaploids
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作者 Yan Niu rui yang +9 位作者 Zelong Li Zhengxuan Huo Shihao Chang Entang Tian Han Qin Wallace A.Cowling Kadambot H.M.Siddique Annaliese S.Mason Sheng Chen Jun Zou 《Journal of Genetics and Genomics》 2025年第6期799-811,共13页
Allopolyploids often exhibit advantages in vigor and adaptability compared to diploids.A long-term goal in the economically important Brassica genus has been to develop a new allohexaploid crop type(AABBCC)by combinin... Allopolyploids often exhibit advantages in vigor and adaptability compared to diploids.A long-term goal in the economically important Brassica genus has been to develop a new allohexaploid crop type(AABBCC)by combining different diploid and allotetraploid crop species.However,early-generation allohexaploids often face challenges like unstable meiosis and low fertility,and the phenotypic performance of these synthetic lines has rarely been assessed.This study analyzes agronomic traits,fertility,and genome stability in ArArBcBcCcCc lines derived from four crosses between B.carinata and B.rapa after 9–11 selfing generations.Our results demonstrate polyploid advantage in vigor and seed traits,considerable phenotypic variation,and high fertility and genome stability.Meanwhile,parental genotypes significantly influence outcomes in advanced allohexaploids.Structural variants,largely resulting from A–C homoeologous exchanges,contribute to genomic variation and influence hexaploid genome stability,with the A sub-genome showing the highest variability.Both positive and negative impacts of SVs on fertility and seed weight are observed.Pseudo-euploids,frequently appearing,do not significantly affect fertility or other agronomic traits compared to euploids,indicating a potential pathway toward a stable allohexaploid species.These findings provide insights into the challenge and potential for developing an adaptable and stable Brassica hexaploid through selection. 展开更多
关键词 Brassica species Synthetic allohexaploid Homoeologous exchange Genome stability Polyploid advantage Structural variants
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Space-marching inverse design of subsonic,transonic,and supersonic internal flowfields
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作者 Bo ZHANG Shihe YI +3 位作者 Yuxin ZHAO rui yang Ziyuan ZHU ruitong ZENG 《Chinese Journal of Aeronautics》 2025年第2期15-30,共16页
Flowfield inverse design can obtain the desired flow and contour with high design efficiency,short design cycle,and small modification need.In this study,the Euler equations are formulated in the stream-function coord... Flowfield inverse design can obtain the desired flow and contour with high design efficiency,short design cycle,and small modification need.In this study,the Euler equations are formulated in the stream-function coordinates and combined with the given boundary conditions to derive a gridless space-marching method for the inverse design of subsonic,transonic,and supersonic flowfields.Designers can prescribe the flow parameters along the reference streamline to design flowfields and aerodynamic contours.The method is validated by the theoretical transonic solution,computational fluid dynamics,and experimental data,respectively.The method supports the fabrication of a Mach 2.0 single expansion tunnel.The calibration data agree well with the prescribed pressure distribution.The method is successfully applied to inverse design of contractions,nozzles,and asymmetric channels.Compared to classical analytic contractions,the contractions designed by the space-marching method provide a more accurate transonic flow.Compared to the classical Sivells’nozzle,the nozzle designed by the space-marching method provides a smaller workload,a more flexible velocity distribution,a 20%reduction in length,and an equally uniform flow.Additionally,the space-marching method is applied to design the asymmetric channels under various Mach numbers.These asymmetric channels perfectly eliminate Mach waves,achieving the shock-free flow turning and high flow uniformity.These results validate the feasibility of the space-marching method,making it a good candidate for the inverse design of subsonic,transonic,and supersonic internal flowfields and aerodynamic contours. 展开更多
关键词 Flowfield Inverse design Compressible flow CONTRACTION Nozzle Asymmetric channel
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Amino acid substitutions in succinate dehydrogenase complex conferring resistance to the SDHI fungicide pydiflumetofen in Cochliobolus heterostrophus causing southern corn leaf blight
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作者 Jiazhi Sun Bingyun yang +7 位作者 Lingmin Xia rui yang Chaoyang Ding yang Sun Xing Chen Chunyan Gu Xue yang Yu Chen 《Journal of Integrative Agriculture》 2025年第7期2670-2685,共16页
Southern corn leaf blight(SCLB)caused by Cochliobolus heterostrophus,is a widespread foliar disease that has a substantial impact on maize yield in the Huang-Huai-Hai Region of China.Pydiflumetofen(Pyd),a new succinat... Southern corn leaf blight(SCLB)caused by Cochliobolus heterostrophus,is a widespread foliar disease that has a substantial impact on maize yield in the Huang-Huai-Hai Region of China.Pydiflumetofen(Pyd),a new succinate dehydrogenase inhibitor(SDHI),has been found as a promising fungicide for the efficient control of SCLB,however,resistance of C.heterostrophus to Pyd has not been studied well.Here,five Pyd-resistant mutants were generated through fungicide adaptation.Sequence alignment analysis revealed that these mutants primarily mutated in ChSdhB and ChSdhD,with three genotypes:ChSdhB^(H277Y),ChSdhB^(I279T)and ChSdhD^(H133Y),exhibiting two distinct categories of resistance:high resistance(HR)and moderate resistance(MR),among which the resistance factors were 214.22 and 44.33-53.67,respectively.These mutants were more pathogenic than the wild-type parental strains,but there was a significant reduction in mycelial growth rate and sporulation in the resistant mutants,indicating a significant fitness cost associated with resistance to Pyd.In addition,this study revealed a positive cross-resistance between Pyd and another SDHI fungicide cyclobutrifluram.However,no cross-resistance was found between Pyd and other classes of fungicides,including prochloraz,fludioxonil,iprodione or pyraclostrobin.Homology modeling and molecular docking further confirmed that point mutations of ChSdhB^(H277Y),ChSdhB^(I279T),and ChSdhD^(H133Y)could reduce binding affinity between Pyd and its target subunits from-74.07,-74.07,-152.52 kcal mol^(-1)to-3.90,-4.95,-9.93 kcal mol^(-1),respectively.These findings not only provided valuable insights for managing SCLB caused by C.heterostrophus,but also enhanced our understanding of molecular mechanism underlying plant pathogen resistance to Pyd. 展开更多
关键词 Cochliobolus heterostrophus pydiflumetofen SDHI resistance resistance mechanism point mutation
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Rethinking Domain-Specific Pretraining by Supervised or Self-Supervised Learning for Chest Radiograph Classification:A Comparative Study Against ImageNet Counterparts in Cold-Start Active Learning
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作者 Han Yuan Mingcheng Zhu +3 位作者 rui yang Han Liu Irene Li Chuan Hong 《Health Care Science》 2025年第2期110-143,共34页
Objective:Deep learning(DL)has become the prevailing method in chest radiograph analysis,yet its performance heavily depends on large quantities of annotated images.To mitigate the cost,cold-start active learning(AL),... Objective:Deep learning(DL)has become the prevailing method in chest radiograph analysis,yet its performance heavily depends on large quantities of annotated images.To mitigate the cost,cold-start active learning(AL),comprising an initialization followed by subsequent learning,selects a small subset of informative data points for labeling.Recent advancements in pretrained models by supervised or self-supervised learning tailored to chest radiograph have shown broad applicability to diverse downstream tasks.However,their potential in cold-start AL remains unexplored.Methods:To validate the efficacy of domain-specific pretraining,we compared two foundation models:supervised TXRV and self-supervised REMEDIS with their general domain counterparts pretrained on ImageNet.Model performance was evaluated at both initialization and subsequent learning stages on two diagnostic tasks:psychiatric pneumonia and COVID-19.For initialization,we assessed their integration with three strategies:diversity,uncertainty,and hybrid sampling.For subsequent learning,we focused on uncertainty sampling powered by different pretrained models.We also conducted statistical tests to compare the foundation models with ImageNet counterparts,investigate the relationship between initialization and subsequent learning,examine the performance of one-shot initialization against the full AL process,and investigate the influence of class balance in initialization samples on initialization and subsequent learning.Results:First,domain-specific foundation models failed to outperform ImageNet counterparts in six out of eight experiments on informative sample selection.Both domain-specific and general pretrained models were unable to generate representations that could substitute for the original images as model inputs in seven of the eight scenarios.However,pretrained model-based initialization surpassed random sampling,the default approach in cold-start AL.Second,initialization performance was positively correlated with subsequent learning performance,highlighting the importance of initialization strategies.Third,one-shot initialization performed comparably to the full AL process,demonstrating the potential of reducing experts'repeated waiting during AL iterations.Last,a U-shaped correlation was observed between the class balance of initialization samples and model performance,suggesting that the class balance is more strongly associated with performance at middle budget levels than at low or high budgets.Conclusions:In this study,we highlighted the limitations of medical pretraining compared to general pretraining in the context of cold-start AL.We also identified promising outcomes related to cold-start AL,including initialization based on pretrained models,the positive influence of initialization on subsequent learning,the potential for one-shot initialization,and the influence of class balance on middle-budget AL.Researchers are encouraged to improve medical pretraining for versatile DL foundations and explore novel AL methods. 展开更多
关键词 chest radiograph analysis cold-start active learning COVID-19 psychiatric pneumonia radiology foundation model
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Pedestrian collision and future work in the restricted indoor space:A state-of-the-art review on influencing factors,behaviors,and methods
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作者 Zhenxiang Tao Ying Li +3 位作者 Xubo Huang Yisen Wang rui yang Hui Zhang 《Chinese Physics B》 2025年第4期173-199,共27页
Emergency evacuation involves rapid transfer of individuals from hazardous areas,where limited time and space can lead to collisions.Although the collision behavior of evacuees has been studied previously,there is a l... Emergency evacuation involves rapid transfer of individuals from hazardous areas,where limited time and space can lead to collisions.Although the collision behavior of evacuees has been studied previously,there is a lack of systematic summaries.This study used the CiteSpace visualization software to analyze keywords in the evacuation collision literature.Based on the frequency of keyword occurrence,we determined the research trend;classified the keywords;and analyzed and summarized their influencing factors,behavioral characteristics,and research methods.Clearly,the evacuation environment and emergency guidance directly affect individual behavior and emotions,mainly affecting gait adjustment and decisionmaking processes,which in turn determine evacuation efficiency and collision risk.In the future,emphasis should be placed on post-collision psychological activities,coping strategies,and the application of virtual and mixed reality technologies to observe the interaction between individuals and the environment and to strengthen evacuation research. 展开更多
关键词 public safety building structure evacuation environment individual collision AVOIDANCE
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Study on the influence of the sY1192 gene locus in the AZFb/c region on sperm quality and pregnancy outcome
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作者 Gang-Xin Chen Yan Sun +3 位作者 rui yang Zhi-Qing Huang Hai-Yan Li Bei-Hong Zheng 《Asian Journal of Andrology》 2025年第2期231-238,共8页
Y chromosome microdeletions are an important cause of male infertility.At present,research on the Y chromosome is mainly focused on analyzing the loss of large segments of the azoospermia factor a/b/c(AZFa/b/c)gene,an... Y chromosome microdeletions are an important cause of male infertility.At present,research on the Y chromosome is mainly focused on analyzing the loss of large segments of the azoospermia factor a/b/c(AZFa/b/c)gene,and few studies have reported the impact of unit point deletion in the AZF band on fertility.This study analyzed the effect of sperm quality after sY1192 loss in 116 patients.The sY1192-independent deletion accounted for 41.4%(48/116).Eight patterns were found in the deletions associated with sY1192.The rate of sperm detection was similar in the semen of patients with the independent sY1192 deletion and the combined sY1192 deletions(52.1%vs 50.0%).The patients with only sY1192 gene loss had a higher probability of sperm detection than the patients whose sY1192 gene locus existed,but other gene loci were lost(52.1%vs 32.0%).The hormone levels were similar in patients with sY1192 deletion alone and in those with sY1192 deletion and other types of microdeletions in the presence of the sY1192 locus.After multiple intracytoplasmic sperm injection(ICSI)attempts,the pregnancy rate of spouses of men with sY1192-independent deletions was similar to that of other types of microdeletions,but the fertilization and cleavage rates were higher.We observed that eight deletion patterns were observed for sY1192 microdeletions of AZFb/c,dominated by the independent deletion of sY1192.After ICSI,the fertilization rate and cleavage rate of the sY1192-independent microdeletion were higher than those of other Y chromosome microdeletion types,but there was no significant difference in pregnancy outcomes. 展开更多
关键词 assisted reproductive technology AZFb/c pregnancy outcome sY1192 Y chromosome microdeletion
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星形胶质细胞介导呼吸调节的研究进展
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作者 辛天元 陈宇 +4 位作者 向倍仪 芮阳 陈昶文 董榕 陈哲 《生物医学工程与临床》 2025年第5期714-718,共5页
星形胶质细胞在呼吸调节中起着重要作用。它们通过感知局部环境中的二氧化碳和pH值变化,在孤束核(NTS)、preB?tzinger复合体及斜体后核等呼吸中枢区域中充当化学感受器,并通过调节钙信号和释放三磷酸腺苷(ATP)直接影响呼吸节律的生成与... 星形胶质细胞在呼吸调节中起着重要作用。它们通过感知局部环境中的二氧化碳和pH值变化,在孤束核(NTS)、preB?tzinger复合体及斜体后核等呼吸中枢区域中充当化学感受器,并通过调节钙信号和释放三磷酸腺苷(ATP)直接影响呼吸节律的生成与维持。星形胶质细胞不仅在生理状态下通过代谢支持、突触稳态调节等机制维持神经元功能,还在病理条件下(如慢性低氧、心力衰竭和神经炎症等)通过炎症反应和代谢失衡造成呼吸调节功能紊乱。近年来,光遗传学、化学遗传学等新技术的应用深入揭示了星形胶质细胞在呼吸中枢中的复杂功能,特别是在病理状态下的调控机制。文章就星形胶质细胞对呼吸的调节作用及机制和神经科学技术在星形胶质细胞参与呼吸调节研究中的应用进行综述。未来的研究将集中整合多学科的研究方法,进一步揭示星形胶质细胞在呼吸调节和相关疾病中的多重功能,为相关疾病的干预和治疗提供理论基础。 展开更多
关键词 星形胶质细胞 呼吸调节 化学感受 病理生理学 呼吸疾病靶点
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Soil and Water Loss Characteristics of Different Forest Stands in Pingjiang
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作者 rui yang Zhangquan ZENG +2 位作者 Yaqin XIAO Canming ZHANG yang SONG 《Meteorological and Environmental Research》 2025年第2期9-11,15,共4页
In this paper,different stands in Xianzhong Nursery of Pingjiang were selected as the research object to study the runoff generation and soil loss characteristics of different stands.The results showed that the annual... In this paper,different stands in Xianzhong Nursery of Pingjiang were selected as the research object to study the runoff generation and soil loss characteristics of different stands.The results showed that the annual surface runoff of each model in Pingjiang was between 50.50 and 70.38 mm,and the annual surface runoff of each stand decreased with years.There was no significant difference in the annual runoff between each stand,nor between each stand and its control.There were significant differences in soil erosion modulus among the models,and the number ranged from 139.20 to 197.79 t/(km^(2)·y). 展开更多
关键词 Pingjiang Forest stand Surface runoff Improving quality and efficiency
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Soil and Water Loss Characteristics of Different Forest Stands in the Dongjiang Lake of Zixing City
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作者 Zhangquan ZENG Yaqin XIAO +2 位作者 Canming ZHANG yang SONG rui yang 《Meteorological and Environmental Research》 2025年第1期51-53,共3页
In this paper,different stands in Dongjiang Lake Reservoir area of Zixing were selected as the research objects,and the runoff generation and soil loss characteristics of different stands were studied.The results show... In this paper,different stands in Dongjiang Lake Reservoir area of Zixing were selected as the research objects,and the runoff generation and soil loss characteristics of different stands were studied.The results showed that the annual surface runoff of each model in Zixing was between 43.24 and 50.99 mm,and there was no significant difference in the annual runoff between each stand and its control.There were significant differences in soil erosion modulus among the models,and the number ranged from 127.37 to 165.58 t/(km 2·y). 展开更多
关键词 Dongjiang Lake Reservoir area Forest stand Surface runoff Forest management
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Roadmaps for sodium-ion batteries to achieve techno-economic competitiveness and commercial success
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作者 Yihua Zhong Xiang Chen +5 位作者 Xianyu Cai Han-Bing Zhu rui yang Yi yang Baofeng yang Qiang Zhang 《Journal of Energy Chemistry》 2025年第9期81-82,I0004,共3页
Rechargeable batteries have changed human daily life from electronic devices and electric transport to renewable energy systems[1-3].Especially,lithium-ion batteries(LIBs)have dominated the market since their first co... Rechargeable batteries have changed human daily life from electronic devices and electric transport to renewable energy systems[1-3].Especially,lithium-ion batteries(LIBs)have dominated the market since their first commercialization in the 1990s,and the three pioneers(John B.Goodenough,M.Stanley Whittingham,and Akira Yoshino)in the historical development of LIBs were awarded the Novel Prize in chemistry in 2019[4].However,the imbalance between supply and demand during the past few years induced extremely huge fluctuations in lithium resources.The misgivings of lithium resources have promoted the quick development of potential alternative battery technologies. 展开更多
关键词 Sodium-ion batteries Lithium-ion batteries Techno-economic competitiveness
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黄河流域特色保护类村庄种群分布动态与生境选择 被引量:4
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作者 王玲 芮旸 +1 位作者 罗飞 孙玮鸿 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期500-512,共13页
基于种群生态学理论,将黄河流域971个国家级特色保护类村庄视作一个地理种群。综合GIS空间分析和数理统计方法,明晰这一种群的分布动态和生境选择特征,进而应用地理探测器对比揭示影响该种群分布的生态因子。结果表明:(1)黄河流域特色... 基于种群生态学理论,将黄河流域971个国家级特色保护类村庄视作一个地理种群。综合GIS空间分析和数理统计方法,明晰这一种群的分布动态和生境选择特征,进而应用地理探测器对比揭示影响该种群分布的生态因子。结果表明:(1)黄河流域特色保护类村庄的分布密度随种群增长而大幅提高,分布模式随尺度变大由显著聚集转为不显著离散,分布格局随时间推移由多中心向单中心演化,但集聚中心一直位于河谷盆地;(2)黄河流域特色保护类村庄具有“聚中低山区、向阳坡斜坡、喜温暖湿润、近黄河干流”的偏好,趋向中等人口密度、经济欠发达地区分布,主要位于国道沿线30 km、省道沿线10 km、中心城市周边20~80 km、历史城镇周边60 km、旅游景区和文保单位周边20 km范围内;(3)影响特色保护类村庄种群分布的生态因子具有综合性、非等价性和限定性,在黄河流域以文保单位和海拔为主导。 展开更多
关键词 特色保护类村庄 地理种群 空间分布 生境选择 黄河流域
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