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不同播期对玉米先玉335产量和品质的影响 被引量:1
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作者 宋艳玲 周广胜 +12 位作者 郭建平 潘亚茹 杨孟娇 田靳峰 李香雪 孟祥祎 兰惠婷 蒋玮光 隋丹 周灵妤 史俊辰 聂畅 满意 《应用气象学报》 CSCD 北大核心 2024年第5期619-628,共10页
利用2018—2023年吉林榆树农业气象试验站玉米大田分期播种试验研究不同播期对玉米生长发育、产量构成和籽粒品质的影响,探讨改变玉米播期作为农业适应气候变化措施的可行性。研究发现:玉米不同播期,玉米生长期内积温利用效率不同,第1... 利用2018—2023年吉林榆树农业气象试验站玉米大田分期播种试验研究不同播期对玉米生长发育、产量构成和籽粒品质的影响,探讨改变玉米播期作为农业适应气候变化措施的可行性。研究发现:玉米不同播期,玉米生长期内积温利用效率不同,第1播期积温最高,第4播期积温比第1播期平均减少8.3%。玉米不同播期对生长期长度造成影响,玉米第1播期生长期长度比第2播期(正常播期)平均延长7.5 d,第3播期较正常播期生长期缩短5.7 d,第4播期较正常播期生长期缩短13.8 d。玉米不同播期对产量结构造成影响,玉米播期提前10 d,6年试验中有2年玉米百粒重增加,4年减少;玉米播期延迟10 d和20 d,玉米百粒重平均减少4.8%和8.7%。玉米播期提前10 d,单株玉米籽粒数增加0.2%,播期延迟10 d和20 d,籽粒数分别减少6.0%和9.3%。总体上,玉米播期延迟10 d和20 d,玉米单产减产10.9%和17.1%。玉米播期提前10 d,平均单产接近正常播期单产,部分年份单产增加。玉米播期对玉米籽粒品质影响不大。气候变暖,东北部分地区玉米播期适当提前可以作为适应气候变化措施。 展开更多
关键词 玉米 播期 适应气候变化措施
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马铃薯发育期模型精度及其对升温的敏感性比较
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作者 王孝贤 王靖 +7 位作者 李扬 陈仁伟 赵凌暄 刘霞霞 胡琦 张祯祯 赵熙玲 赵庚云 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2024年第6期1009-1022,共14页
马铃薯是世界第四大主粮作物,马铃薯发育期的准确模拟是评估气候变化对马铃薯生长发育影响的基础。通过研究筛选在全国马铃薯种植区发育期模拟效果最优的模型,并基于模型探究历史气候变化对马铃薯生育期的影响差异以及模型对升温(1~5℃... 马铃薯是世界第四大主粮作物,马铃薯发育期的准确模拟是评估气候变化对马铃薯生长发育影响的基础。通过研究筛选在全国马铃薯种植区发育期模拟效果最优的模型,并基于模型探究历史气候变化对马铃薯生育期的影响差异以及模型对升温(1~5℃)的敏感性,可为模型改进提供方向。针对当前对覆盖不同气候和品种类型的发育期模型综合对比研究较少,本研究选取3种温度响应函数与2种日长响应函数,组合形成3种温度模型和6种光温模型,运用模拟退火算法对模型进行调参,对比其在全国8个站点模拟马铃薯全生育期的精度,结果表明:1)线性温度函数+负指数日长函数光温模型(M3)、Logistic温度函数+负指数日长函数光温模型(M6)和Beta温度函数+负指数日长函数光温模型(M9)的模拟效果最优, 3个模型模拟和观测的全生育期长度RMSE分别为7.7 d、6.8 d和7.1 d, R^(2)均大于0.90。2)基于最优模型在4个代表性站点的模拟结果显示,历史气候变化导致马铃薯生育期总体呈缩短趋势,但在不同站点模型间存在差异。3)升温1~5℃,模型M3和M6模拟的马铃薯全生育期日数呈线性缩短,每升温1℃, 4个站点的生育期缩短3.0~8.2 d;而模型M9模拟的全生育期日数呈非线性变化,随温度升高生育期缩短趋势先增加后减小。筛选出的3种光温模型均可有效模拟马铃薯发育期;基于3种模型模拟的历史气候变化总体均使马铃薯生育期缩短,但变化率不同;温度响应函数的不同,使得3种模型对升温的敏感性不同,且模型间差异随着升温而增加。研究结果为马铃薯发育期模型选择和改进提供了重要参考。 展开更多
关键词 气候变化 马铃薯 生育期 温度升高 发育期模型 光温模型 模拟退火算法
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不同贮藏方式对黄变发酵萝卜贮藏稳定性的影响
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作者 曾雪晴 赵楠 +3 位作者 杨馨雨 林长彬 黄巧莲 葛黎红 《中国酿造》 CAS 北大核心 2024年第4期186-191,共6页
为了探究不同包装(真空、盐水)及温度(10℃、20℃、30℃)对黄变发酵萝卜贮藏期间品质的影响,对不同贮存方式的萝卜在贮藏过程中颜色参数、质构及理化指标变化进行分析测定。结果表明,10℃条件下盐水包装能更好稳定萝卜的金黄色泽,延缓萝... 为了探究不同包装(真空、盐水)及温度(10℃、20℃、30℃)对黄变发酵萝卜贮藏期间品质的影响,对不同贮存方式的萝卜在贮藏过程中颜色参数、质构及理化指标变化进行分析测定。结果表明,10℃条件下盐水包装能更好稳定萝卜的金黄色泽,延缓萝卜L*值下降、褐变及质构软化。10℃条件下贮藏7 d,盐水包装萝卜L*值、硬度、咀嚼性分别为66.04、10621.81 N、3331.42 mJ,比其他处理组分别高2.93%~31.68%、0.48%~27.65%、3.44%~48.07%;10℃条件下贮藏14 d,盐水包装萝卜还原糖为4.77 g/100 g,比其他组高2.80%~26.19%,细菌对数值降低0.42~0.96 lg(CFU/mL),完全抑制乳酸菌和酵母菌生长。10℃贮藏过程中,盐水包装萝卜pH较稳定,亚硝酸盐未超标(<1.0 mg/kg)且显著低于其他处理(P<0.05)。因此,10℃条件下盐水包装可维持萝卜在贮藏过程中的品质,延缓萝卜褐变,稳定萝卜的金黄色泽和质构。 展开更多
关键词 黄变发酵萝卜 色泽 包装方式 理化指标 贮藏品质
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中国北方地区四种熟型藜属杂草始花期的模拟
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作者 郭家驹 胡梦琪 +7 位作者 张琳晗 郭博雅 祝令帅 刘冬 王雨欣 林楠 李秋月 徐琳 《草地学报》 CAS CSCD 北大核心 2024年第6期1872-1881,共10页
藜属(Chenopodium)草本植物是我国常见杂草,其花粉量大,持续时间长,致敏性强,对大气环境质量和人类健康都有一定危害,尤其在气候变化和退耕还林还草背景下,致敏风险增加。为精准预报藜属杂草始花期,本文基于中国北方地区1981—2018年52... 藜属(Chenopodium)草本植物是我国常见杂草,其花粉量大,持续时间长,致敏性强,对大气环境质量和人类健康都有一定危害,尤其在气候变化和退耕还林还草背景下,致敏风险增加。为精准预报藜属杂草始花期,本文基于中国北方地区1981—2018年52个站点的藜属杂草始花期实测数据,构建了5种基于逐日气温、降水、光周期序列驱动的物候过程模型,并进行了参数率定和优选。结果表明,温度是主导始花期的环境因子,光周期也起着重要的调控作用,而冷激对4种熟型藜属杂草始花期的影响并不显著。此外在干旱区考虑降水因子进行藜属杂草始花期预报是有必要的,干旱会延迟藜属杂草始花期,而降水则能起到一定的促进作用。本研究可作为我国北方地区藜属杂草花粉花期预报的辅助手段,为防治藜属杂草花粉过敏提供帮助。 展开更多
关键词 藜属 花期预报 物候模型 干旱 光周期
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谚语“冷在三九、热在三伏”的气象学验证
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作者 周建朔 胡琦 +6 位作者 楚希雅 张科 马雪晴 姜婧妍 张丽娜 潘学标 王靖 《气象研究与应用》 2024年第3期74-79,共6页
基于1961—2020年中国内地七个行政区域585个气象观测站日平均温度、最低气温、最高气温的频率和时空分布特征,进行谚语“冷在三九、热在三伏”的适用性分析和验证。结果表明,中国冬季气温最低值主要发生在“一九”至“六九”时段,在“... 基于1961—2020年中国内地七个行政区域585个气象观测站日平均温度、最低气温、最高气温的频率和时空分布特征,进行谚语“冷在三九、热在三伏”的适用性分析和验证。结果表明,中国冬季气温最低值主要发生在“一九”至“六九”时段,在“三九”时段的发生频率最大为25.8%。结合日最高温度和平均温度分析,“热在三伏”发生频率为61.2%。受纬度和地形影响,整体呈现中部高南北低的特征。 展开更多
关键词 气候变化 气象谚语 温度
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基于光周期和温度的物候模型对华北平原刺槐始花期的模拟
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作者 林楠 刘冬 +6 位作者 王雨欣 王姝纯 卢凡青 王淼 张煦庭 李秋月 徐琳 《生态学报》 CAS CSCD 北大核心 2024年第9期3745-3758,共14页
光周期和温度是影响木本植物开花的两大关键气象因素。基于我国华北平原1963—2018年57个站点的刺槐始花期实测数据,构建了6种基于气温或光周期驱动的春季物候过程模型(积温模型、光周期模型、光周期-温度顺序模型、温度-光周期顺序模... 光周期和温度是影响木本植物开花的两大关键气象因素。基于我国华北平原1963—2018年57个站点的刺槐始花期实测数据,构建了6种基于气温或光周期驱动的春季物候过程模型(积温模型、光周期模型、光周期-温度顺序模型、温度-光周期顺序模型、光周期-温度平行模型、光周期-温度乘法模型),并进行了参数率定和模型比较优选,以期明确刺槐开花的主导驱动因子以及潜在的光温作用机制。根据内部模拟的赤池信息准则(AIC)判定光周期-温度顺序模型的表现最佳,模拟值与观测值的相关系数(r)为0.86,均方根误差(RMSE)为4.81d,纳什效率系数(NSE)达到0.74,说明刺槐始花期的发生同时受到光周期和温度的作用。同时,在华北平原14个代表性站点上,光周期-温度顺序模型的表现普遍优于均值模型。基于光周期-温度顺序模型的参数率定结果,以下限温度6.5℃和下限日长4.5h来统计刺槐开花的实际有效积温量和实际有效日长累积量的年际变化情况,结果表明56年来刺槐开花的实际有效积温量呈现显著递增趋势,平均每10年增加4.5℃·d(P<0.05),而实际有效日长累积量却呈现极显著递减趋势,平均每10年减少23.9h·d(P<0.01),这说明在气候变暖背景下,刺槐开花的热量需求会更快速完成,引起刺槐开花日期的提前,但自然光周期的年内变化只与地理位置有关,日长累积需求则需要更长的时间完成,因此会在一定程度上抑制春季升温引起的开花日期提前。 展开更多
关键词 光周期 温度 刺槐 始花期 物候模型
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王强教授应用寒痉汤化裁治疗寒痹的临床经验
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作者 蔺妍钰 蔺春彦 王强(指导) 《中国民族民间医药》 2024年第11期57-59,63,共4页
总结王强教授在临床上应用寒痉汤化裁治疗寒痹的经验。文章从寒痹的归属范围、病因病机、其对寒痹的诊疗经验、寒痉汤的方药分析等进行论述。寒痹是以肢体关节疼痛为主要临床表现的病症,且有“得温则痛减,得寒痛加重”的特性。王强教授... 总结王强教授在临床上应用寒痉汤化裁治疗寒痹的经验。文章从寒痹的归属范围、病因病机、其对寒痹的诊疗经验、寒痉汤的方药分析等进行论述。寒痹是以肢体关节疼痛为主要临床表现的病症,且有“得温则痛减,得寒痛加重”的特性。王强教授认为引起寒痹的原因不外乎是内虚外寒,多是由机体感受寒邪,经脉闭塞不通所致,并提出了发汗驱寒是治疗本病的一大法则。王强教授另辟思路,运用寒痉汤化裁治疗寒痹,丰富了本病诊疗辨证经验,值得学习和借鉴。 展开更多
关键词 寒痹 痉脉 疼痛 寒痉汤
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Trend of Developing Aqueous Liquid and Gel Electrolytes for Sustainable,Safe,and High‑Performance Li‑Ion Batteries 被引量:2
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作者 Donghwan Ji Jaeyun Kim 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期17-34,共18页
Current lithium-ion batteries(LIBs)rely on organic liquid electrolytes that pose significant risks due to their flammability and toxicity.The potential for environmental pollution and explosions resulting from battery... Current lithium-ion batteries(LIBs)rely on organic liquid electrolytes that pose significant risks due to their flammability and toxicity.The potential for environmental pollution and explosions resulting from battery damage or fracture is a critical concern.Water-based(aqueous)electrolytes have been receiving attention as an alternative to organic electrolytes.However,a narrow electrochemicalstability window,water decomposition,and the consequent low battery operating voltage and energy density hinder the practical use of aqueous electrolytes.Therefore,developing novel aqueous electrolytes for sustainable,safe,high-performance LIBs remains challenging.This Review first commences by summarizing the roles and requirements of electrolytes–separators and then delineates the progression of aqueous electrolytes for LIBs,encompassing aqueous liquid and gel electrolyte development trends along with detailed principles of the electrolytes.These aqueous electrolytes are progressed based on strategies using superconcentrated salts,concentrated diluents,polymer additives,polymer networks,and artificial passivation layers,which are used for suppressing water decomposition and widening the electrochemical stability window of water of the electrolytes.In addition,this Review discusses potential strategies for the implementation of aqueous Li-metal batteries with improved electrolyte–electrode interfaces.A comprehensive understanding of each strategy in the aqueous system will assist in the design of an aqueous electrolyte and the development of sustainable and safe high-performance batteries. 展开更多
关键词 Lithium-ion battery(LIB) Aqueous electrolyte Gel electrolyte Electrochemical stability window Li dendrite
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低温等离子体杀菌技术对泡菜源混菌体系杀菌效果的研究
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作者 梅源 葛黎红 +4 位作者 杨锐 黄玉立 杨梦露 扎西达瓦 赵楠 《中国酿造》 CAS 北大核心 2024年第3期189-193,共5页
该研究制备了泡菜源的3种乳酸菌和2种酵母组成的混菌体系,并考察不同低温等离子体杀菌(CPS)处理对泡菜源微生物模拟混菌体系的杀菌效果,并评估混菌体系的产膜、产气、产酸和耐酸特性。结果表明,当放电电压相同、处理时间相同时,5种微生... 该研究制备了泡菜源的3种乳酸菌和2种酵母组成的混菌体系,并考察不同低温等离子体杀菌(CPS)处理对泡菜源微生物模拟混菌体系的杀菌效果,并评估混菌体系的产膜、产气、产酸和耐酸特性。结果表明,当放电电压相同、处理时间相同时,5种微生物的存活率均随处理时间、放电电压的增加而降低。当处理时间≥9 min时,放电电压越高,膜璞积累量及产气能力下降;但产气效果差异不明显。最佳CPS处理条件为放电电压160 k V,处理时间9 min。在此优化条件下,当发酵31 h时,混菌体系中微生物生物量(OD_(600 nm)值)最低(1.35),有效减缓了乳酸菌和酵母菌的生长;pH值最高(4.12),抑制了微生物产酸,一定程度上缓解了后酸化。 展开更多
关键词 低温等离子体杀菌 乳酸菌 酵母菌 混菌体系 泡菜
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乳酸菌与酵母菌互作对萝卜泡菜发酵进程及风味品质的影响
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作者 黄玉立 葛黎红 +3 位作者 马思尧 梅源 卢伟 赵楠 《中国酿造》 CAS 北大核心 2024年第4期197-202,共6页
为了明确萝卜泡菜发酵过程中的乳酸菌和酵母菌互作对其发酵进程及风味的影响,该研究通过以无菌盐水发酵萝卜作为对照组(CK),考察植物乳杆菌(Lactobacillus plantarum,Lp)、甘草乳杆菌(Liquorilactobacillus nagelii,Ln)和少孢哈萨克斯... 为了明确萝卜泡菜发酵过程中的乳酸菌和酵母菌互作对其发酵进程及风味的影响,该研究通过以无菌盐水发酵萝卜作为对照组(CK),考察植物乳杆菌(Lactobacillus plantarum,Lp)、甘草乳杆菌(Liquorilactobacillus nagelii,Ln)和少孢哈萨克斯坦酵母(Kazachstania exigua,Ke)单菌和混菌(总接种量均为1%)的条件下萝卜泡菜发酵过程中微生物、理化参数的变化,并对比分析了不同菌种发酵终点的挥发性风味物质差异,并对挥发性风味成分进行正交偏最小二乘法判别分析(OPLS-DA)和层次聚类分析(HCA)。结果表明,随着发酵的进行,不同处理组中乳酸菌数量和菌落总数的变化无明显差异,而酵母数量和还原糖含量在单乳酸菌组和CK组中的变化规律一致,并与混菌组呈显著性差异(P<0.05);Lp+Ln+Ke(1:1:1)组的产酸速度和最终酸积累量依次高于双菌发酵组和单菌组。挥发性风味物质分析表明,混菌发酵比单菌发酵产生的风味物质更丰富,且乙酸乙酯仅在Lp+Ln+Ke(1:1:1)组检测到。OPLS-DA和HCA结果表明,可以将不同菌种发酵的泡菜进行有效区分。以上结果表明,多乳酸菌与酵母菌互作,提高了萝卜泡菜发酵进程及品质。 展开更多
关键词 泡菜 乳酸菌 酵母菌 相互作用 挥发性风味物质
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Postbiotics from Saccharomyces cerevisiae fermentation stabilize microbiota in rumen liquid digesta during grain-based subacute ruminal acidosis(SARA) in lactating dairy cows
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作者 Junfei Guo Zhengxiao Zhang +3 位作者 Le Luo Guan Ilkyu Yoon Jan C.Plaizier Ehsan Khafipour 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2059-2080,共22页
Background Subacute ruminal acidosis(SARA)is a common metabolic disorder of high yielding dairy cows,and it is associated with dysbiosis of the rumen and gut microbiome and host inflammation.This study evaluated the i... Background Subacute ruminal acidosis(SARA)is a common metabolic disorder of high yielding dairy cows,and it is associated with dysbiosis of the rumen and gut microbiome and host inflammation.This study evaluated the impact of two postbiotics from Saccharomyces cerevisiae fermentation products(SCFP)on rumen liquid associated microbiota of lactating dairy cows subjected to repeated grain-based SARA challenges.A total of 32 rumen cannulated cows were randomly assigned to 4 treatments from 4 weeks before until 12 weeks after parturition.Treatment groups included a Control diet or diets supplemented with postbiotics(SCFPa,14 g/d Original XPC;SCFPb-1X,19 g/d Nutri Tek;SCFPb-2X,38 g/d Nutri Tek,Diamond V,Cedar Rapids,IA,USA).Grain-based SARA challenges were conducted during week 5(SARA1)and week 8(SARA2)after parturition by replacing 20%DM of the base total mixed ration(TMR)with pellets containing 50%ground barley and 50%ground wheat.Total DNA from rumen liquid samples was subjected to V3–V416S r RNA gene amplicon sequencing.Characteristics of rumen microbiota were compared among treatments and SARA stages.Results Both SARA challenges reduced the diversity and richness of rumen liquid microbiota,altered the overall composition(β-diversity),and its predicted functionality including carbohydrates and amino acids metabolic pathways.The SARA challenges also reduced the number of significant associations among different taxa,number of hub taxa and their composition in the microbial co-occurrence networks.Supplementation with SCFP postbiotics,in particular SCFPb-2X,enhanced the robustness of the rumen microbiota.The SCFP supplemented cows had less fluctuation in relative abundances of community members when exposed to SARA challenges.The SCFP supplementation promoted the populations of lactate utilizing and fibrolytic bacteria,including members of Ruminococcaceae and Lachnospiraceae,and also increased the numbers of hub taxa during non-SARA and SARA stages.Supplementation with SCFPb-2X prevented the fluctuations in the abundances of hub taxa that were positively correlated with the acetate concentration,andα-andβ-diversity metrics in rumen liquid digesta.Conclusions Induction of SARA challenges reduced microbiota richness and diversity and caused fluctuations in major bacterial phyla in rumen liquid microbiota in lactating dairy cows.Supplementation of SCFP postbiotics could attenuate adverse effects of SARA on rumen liquid microbiota. 展开更多
关键词 Postbiotics Rumen microbiota Saccharomyces cerevisiae fermentation products SARA
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Promoting role of Ru species on Ir-Fe/BN catalyst in 1,2-diols hydrogenolysis to secondary alcohols
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作者 Ben Liu Yoshinao Nakagawa +1 位作者 Mizuho Yabushita Keiichi Tomishige 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期89-102,共14页
Noble metal-based-bimetallic catalysts have been highly investigated and applied in wide applications including biomass transformation via regioselective C−O hydrogenolysis while further modification especially with n... Noble metal-based-bimetallic catalysts have been highly investigated and applied in wide applications including biomass transformation via regioselective C−O hydrogenolysis while further modification especially with noble metal is highly promising yet still under investigation.Herein,Ru was found as an effective modifier among the screened noble metals(Ru,Pt,Rh,Pd,Au,and Ag)for Ir-Fe/BN(Ir=5 wt%,Fe/Ir=0.25)catalyst in terminal C−O hydrogenolysis of 1,2-butanediol(1,2-BuD)to 2-butanol(2-BuOH).Only trace amount of Ru(up to 0.5 wt%)was effective in terms of high 2-BuOH selectivity(>60%)and activity(about twice).Larger amount of Ru species(3 wt%)highly enhanced the activity but gave low selectivity to 2-BuOH with by-products of terminal C−C bond scission.Optimized catalyst(Ru(0.5)-Ir-Fe/BN)was reusable at least 4 times and gave moderate 2-BuOH yield(47%)in hydrogenolysis of 1,2-BuD.The promoting effect of Ru addition(0.5 wt%)to Ir-Fe/BN on hydrogenolysis of various alcohols was also confirmed.Combining catalytic tests with various characterizations,the promotion mechanism of Ru species in trimetallic catalysts was clarified.The Ru species in Ru(0.5)-Ir-Fe/BN form alloy with Ir and are enriched at the interface with BN surface,and direct interaction between Ru and Fe was not necessary in Ru-Ir-Fe alloy.The interface of Ir and Fe on the surface of Ir-Fe alloy may work as active sites for 1,2-diols to secondary alcohols via direct C−O hydrogenolysis,in which Ru-modified Ir activates H_(2) to form hydride-like species.The activity of Ru species in C−C bond cleavage was highly suppressed due to the direct interaction with Ir species and less exposed to substrate.Larger loading amount of Ru species(3 wt%)led to the formation Ru-rich trimetallic alloy,which further works as active sites for C−C bond scission. 展开更多
关键词 Biomass-based polyols Secondary alcohol HYDRODEOXYGENATION Trimetallic alloy Boron nitride
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Bacteria colonization and gene expression related to immune function in colon mucosa is associated with growth in neonatal calves regardless of live yeast supplementation
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作者 Koki Nishihara Clothilde Villot +2 位作者 Lautaro Cangiano Le Luo Guan Michael Steele 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期1980-1995,共16页
Background As Holstein calves are susceptible to gastrointestinal disorders during the first week of life,understanding how intestinal immune function develops in neonatal calves is important to promote better intesti... Background As Holstein calves are susceptible to gastrointestinal disorders during the first week of life,understanding how intestinal immune function develops in neonatal calves is important to promote better intestinal health.Feeding probiotics in early life may contribute to host intestinal health by facilitating beneficial bacteria colonization and developing intestinal immune function.The objective of this study was to characterize the impact of early life yeast supplementation and growth on colon mucosa-attached bacteria and host immune function.Results Twenty Holstein bull calves received no supplementation(CON)or Saccharomyces cerevisiae boulardii(SCB)from birth to 5 d of life.Colon tissue biopsies were taken within 2 h of life(D0)before the first colostrum feeding and 3 h after the morning feeding at d 5 of age(D5)to analyze mucosa-attached bacteria and colon transcriptome.Metagenome sequencing showed that there was no difference inαandβdiversity of mucosa-attached bacteria between day and treatment,but bacteria related to diarrhea were more abundant in the colon mucosa on D0 compared to D5.In addition,q PCR indicated that the absolute abundance of Escherichia coli(E.coli)decreased in the colon mucosa on D5 compared to D0;however,that of Bifidobacterium,Lactobacillus,and Faecalibacterium prausnitzii,which could competitively exclude E.coli,increased in the colon mucosa on D5 compared to D0.RNA-sequencing showed that there were no differentially expressed genes between CON and SCB,but suggested that pathways related to viral infection such as“Interferon Signaling”were activated in the colon mucosa of D5 compared to D0.Conclusions Growth affected mucosa-attached bacteria and host immune function in the colon mucosa during the first 5 d of life in dairy calves independently of SCB supplementation.During early life,opportunistic pathogens may decrease due to intestinal environmental changes by beneficial bacteria and/or host immune function.Predicted activation of immune function-related pathways may be the result of host immune function development or suggest other antigens in the intestine during early life.Further studies focusing on the other antigens and host immune function in the colon mucosa are required to better understand intestinal immune function development. 展开更多
关键词 Colon biopsy Dairy calves RNA-sequencing Saccharomyces cerevisiae boulardii 16S rRNA amplicon-sequencing
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Gas microchannel plate-pixel detector for X-ray polarimetry
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作者 Huan-Bo Feng Hong-Bang Liu +16 位作者 Dong Wang Zi-Li Li Shu-Lin Liu Qian Liu Hang-Zhou Li Bin-Long Wang Yan-Jun Xie Zong-Wang Fan Hui Wang Ran Chen Di-Fan Yi Rui-Ting Ma Fei Xie Bo Peng Xiang-Ming Sun Jin Li En-Wei Liang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期60-73,共14页
POLAR-2 is a gamma-ray burst(GRB)polarimeter that is designed to study the polarization in GRB radiation emissions,aiming to improve our knowledge of related mechanisms.POLAR-2 is expected to utilize an on-board polar... POLAR-2 is a gamma-ray burst(GRB)polarimeter that is designed to study the polarization in GRB radiation emissions,aiming to improve our knowledge of related mechanisms.POLAR-2 is expected to utilize an on-board polarimeter that is sensitive to soft X-rays(2-10 keV),called low-energy polarization detector.We have developed a new soft X-ray polari-zation detector prototype based on gas microchannel plates(GMCPs)and pixel chips(Topmetal).The GMCPs have bulk resistance,which prevents charging-up effects and ensures gain stability during operation.The detector is composed of low outgassing materials and is gas-sealed using a laser welding technique,ensuring long-term stability.A modulation factor of 41.28%±0.64% is obtained for a 4.5 keV polarized X-ray beam.A residual modulation of 1.96%±0.58% at 5.9 keV is observed for the entire sensitive area. 展开更多
关键词 X-ray polarimetry Gas microchannel plate-pixel detector Gamma-ray bursts
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Effects of improved amino acid balance diet on lysine mammary utilization, whole body protein turnover and muscle protein breakdown on lactating sows
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作者 Sai Zhang Juan C.Marini +4 位作者 Vengai Mavangira Andrew Claude Julie Moore Mahmoud A.Mohammad Nathalie L.Trottier 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2031-2043,共13页
Background The study objective was to test the hypothesis that low crude protein(CP)diet with crystalline amino acids(CAA)supplementation improves Lys utilization efficiency for milk production and reduces protein tur... Background The study objective was to test the hypothesis that low crude protein(CP)diet with crystalline amino acids(CAA)supplementation improves Lys utilization efficiency for milk production and reduces protein turnover and muscle protein breakdown.Eighteen lactating multiparous Yorkshire sows were allotted to 1 of 2 isocaloric diets(10.80 MJ/kg net energy):control(CON;19.24%CP)and reduced CP with“optimal”AA profile(OPT;14.00%CP).Sow body weight and backfat were recorded on d 1 and 21 of lactation and piglets were weighed on d 1,14,18,and 21 of lactation.Between d 14 and 18,a subset of 9 sows(CON=4,OPT=5)was infused with a mixed solution of 3-[methyl-2H3]histidine(bolus injection)and[13C]bicarbonate(priming dose)first,then a constant 2-h[13C]bicarbonate infusion followed by a 6-h primed constant[1-13C]lysine infusion.Serial blood and milk sampling were performed to determine plasma and milk Lys enrichment,Lys oxidation rate,whole body protein turnover,and muscle protein breakdown.Results Over the 21-d lactation period,compared to CON,sows fed OPT had greater litter growth rate(P<0.05).Compared to CON,sows fed OPT had greater efficiency of Lys(P<0.05),Lys mammary flux(P<0.01)and whole-body protein turnover efficiency(P<0.05).Compared to CON,sows fed OPT tended to have lower whole body protein breakdown rate(P=0.069).Muscle protein breakdown rate did not differ between OPT and CON(P=0.197).Conclusion Feeding an improved AA balance diet increased efficiency of Lys and reduced whole-body protein turnover and protein breakdown.These results imply that the lower maternal N retention observed in lactating sows fed improved AA balance diets in previous studies may be a result of greater partitioning of AA towards milk rather than greater body protein breakdown. 展开更多
关键词 Amino acid Efficiency Lactating sows Protein breakdown Protein turnover Reduced protein diet
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Highly Aligned Ternary Nanofiber Matrices Loaded with MXene Expedite Regeneration of Volumetric Muscle Loss
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作者 Moon Sung Kang Yeuni Yu +5 位作者 Rowoon Park Hye Jin Heo Seok Hyun Lee Suck Won Hong Yun Hak Kim Dong‑Wook Han 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期269-292,共24页
Current therapeutic approaches for volumetric muscle loss(VML)face challenges due to limited graft availability and insufficient bioactivities.To overcome these limitations,tissue-engineered scaffolds have emerged as ... Current therapeutic approaches for volumetric muscle loss(VML)face challenges due to limited graft availability and insufficient bioactivities.To overcome these limitations,tissue-engineered scaffolds have emerged as a promising alternative.In this study,we developed aligned ternary nanofibrous matrices comprised of poly(lactide-co-ε-caprolactone)integrated with collagen and Ti_(3)C_(2)T_(x)MXene nanoparticles(NPs)(PCM matrices),and explored their myogenic potential for skeletal muscle tissue regeneration.The PCM matrices demonstrated favorable physicochemical properties,including structural uniformity,alignment,microporosity,and hydrophilicity.In vitro assays revealed that the PCM matrices promoted cellular behaviors and myogenic differentiation of C2C12 myoblasts.Moreover,in vivo experiments demonstrated enhanced muscle remodeling and recovery in mice treated with PCM matrices following VML injury.Mechanistic insights from next-generation sequencing revealed that MXene NPs facilitated protein and ion availability within PCM matrices,leading to elevated intracellular Ca^(2+)levels in myoblasts through the activation of inducible nitric oxide synthase(i NOS)and serum/glucocorticoid regulated kinase 1(SGK1),ultimately promoting myogenic differentiation via the m TOR-AKT pathway.Additionally,upregulated i NOS and increased NO–contributed to myoblast proliferation and fiber fusion,thereby facilitating overall myoblast maturation.These findings underscore the potential of MXene NPs loaded within highly aligned matrices as therapeutic agents to promote skeletal muscle tissue recovery. 展开更多
关键词 Ti_(3)C_(2)T_(x)MXene nanoparticle Ternary nanofibrous matrices Myogenesis Regeneration of volumetric muscle loss Next generation sequencing
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基于医院的延续性护理模式干预对静脉血栓栓塞症患者术后焦虑抑郁情绪及生活质量的影响 被引量:5
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作者 张桂凌 肖影 +1 位作者 张洁 孙玉玺 《临床心身疾病杂志》 CAS 2023年第1期131-134,143,共5页
目的基于医院的延续性护理模式干预对静脉血栓栓塞症患者术后焦虑抑郁情绪及生活质量的影响,为建立延续性护理模式及静脉疾病专病数据库提供依据。方法将90例静脉血栓栓塞症患者按不同干预方法分为研究组和对照组,每组45例。住院期间两... 目的基于医院的延续性护理模式干预对静脉血栓栓塞症患者术后焦虑抑郁情绪及生活质量的影响,为建立延续性护理模式及静脉疾病专病数据库提供依据。方法将90例静脉血栓栓塞症患者按不同干预方法分为研究组和对照组,每组45例。住院期间两组均接受常规抗凝治疗、手术治疗及护理干预,出院后对照组给予常规家庭护理干预,研究组给予基于医院的延续性护理模式干预,观察6个月。比较出院时及出院3个月、6个月两组焦虑自评量表、抑郁自评量表和中文版静脉功能不全患者生活质量/症状问卷子问卷评分,比较出院后6个月两组护理满意度。结果出院3个月、6个月研究组焦虑自评量表、抑郁自评量表评分均较出院时显著降低(P<0.01),且显著低于对照组(P<0.01),对照组出院6个月焦虑自评量表、抑郁自评量表评分均较出院时显著升高(P<0.01)。研究组仅出院6个月中文版静脉功能不全患者生活质量/症状问卷子问卷评分均较出院时显著降低(P<0.01),但出院3个月、6个月仍显著高于对照组(P<0.01),对照组出院3个月、6个月评分均较出院时显著降低(P<0.01)。出院6个月研究组护理总满意率显著高于对照组(P<0.01)。结论基于医院的延续性护理模式干预能有效缓解静脉血栓栓塞症患者术后焦虑、抑郁情绪,提高其生活质量及护理满意度。 展开更多
关键词 静脉血栓栓塞症 延续性护理 焦虑 抑郁 生活质量 护理满意度
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计算弥散加权成像联合瘤周DWI高信号征象评估胶质瘤IDH-1基因分型的临床应用
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作者 王晓青 曹梦秋 +4 位作者 程佳慧 张一铭 吴洪 张晓华 周滟 《中国医学计算机成像杂志》 CSCD 北大核心 2023年第2期111-116,共6页
目的:探讨计算弥散加权成像(cDWI)拟合得到的高b值DWI图像及瘤周DWI高信号(NePDH)征象在区分不同IDH-1基因型胶质瘤中的临床价值。方法:回顾性纳入60例Ⅱ~Ⅳ级胶质瘤患者(IDH-1突变型25例,野生型35例),均行常规MRI平扫、增强及DWI(b=0、... 目的:探讨计算弥散加权成像(cDWI)拟合得到的高b值DWI图像及瘤周DWI高信号(NePDH)征象在区分不同IDH-1基因型胶质瘤中的临床价值。方法:回顾性纳入60例Ⅱ~Ⅳ级胶质瘤患者(IDH-1突变型25例,野生型35例),均行常规MRI平扫、增强及DWI(b=0、1000、3000 s/mm^(2))扫描。使用cDWI技术将DWI_(0,1000)拟合得到cDWI_(0,3000)图像。比较DWI_(0,3000)、cDWI_(0,3000)图像的信噪比(SNR)、对比噪声比(CNR),及医师判读NePDH征象的一致性。评价NePDH征象阳性、肿瘤实质区域表观弥散系数(ADC)_(0,1000)与IDH-1基因型的相关性。绘制受试者工作特征(ROC)曲线并评价各参数的诊断效能。结果:cDWI_(0,3000)图像SNR、CNR优于DWI_(0,3000)(P<0.05)。医师在DWI_(0,3000)、cDWI_(0,3000)上判读NePDH征象的一致性极高(κ=0.958)。不同IDH-1基因型组间,cDWI_(0,3000)上NePDH征象阳性例数差异具有统计学意义(P<0.05),且诊断效能与DWI_(0,3000)相仿(P>0.05)。NePDH征象结合肿瘤实质区ADC值诊断的灵敏度为96.00%,特异度为71.4%,ROC曲线下面积达0.834。结论:高b值cDWI及NePDH征象为术前诊断胶质瘤IDH-1基因型提供了一种无创、可靠的方法。 展开更多
关键词 磁共振成像 弥散加权成像 脑胶质瘤 IDH-1基因 基因分型
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体验经济视角下医学期刊编辑为作者提供人性化服务的困境的质性研究
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作者 戴丽 胡永国 +1 位作者 黄文杰 吴宗辉 《学术出版与传播》 2023年第1期177-183,共7页
目前,我国极力倡导“把论文写在祖国大地上”,而当下我国优秀医学论文外流的现象较突出。鉴于此,医学期刊理应为培育优秀作者、吸引优秀论文做好基础性工作,保障我国医学科研成果。本研究采用质性研究方法,从医学期刊编辑角度,发现影响... 目前,我国极力倡导“把论文写在祖国大地上”,而当下我国优秀医学论文外流的现象较突出。鉴于此,医学期刊理应为培育优秀作者、吸引优秀论文做好基础性工作,保障我国医学科研成果。本研究采用质性研究方法,从医学期刊编辑角度,发现影响期刊为作者提供人性化服务的原因包括:编辑部人员配套不足、工作任务繁杂、工作要求高、职业发展自信不强、人性化服务意识不强,并结合实际从主办单位、编辑部、编辑三个层面提出相应对策。 展开更多
关键词 体验经济学 医学期刊编辑 投稿体验
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基于站点数据分析中国大陆区域喜凉/温作物界限温度的时空演变 被引量:9
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作者 和骅芸 胡琦 +4 位作者 唐书玥 赵金媛 潘学标 潘志华 王靖 《中国农业气象》 CSCD 北大核心 2023年第2期85-95,共11页
喜凉/温作物界限温度的时空分布能够影响作物物候和种植区域。利用全国585个气象站点1961-2020年地面气象观测资料,以喜凉/温作物界限温度(0℃和10℃)的积温、初日、终日作为农业热量资源研究指标,基于ANUSPLIN气象插值软件,从年际和年... 喜凉/温作物界限温度的时空分布能够影响作物物候和种植区域。利用全国585个气象站点1961-2020年地面气象观测资料,以喜凉/温作物界限温度(0℃和10℃)的积温、初日、终日作为农业热量资源研究指标,基于ANUSPLIN气象插值软件,从年际和年代际时间尺度分析1961-2020年喜凉/温作物界限温度的时空演变特征,并探讨热量资源变化对全国农业生产格局的影响。结果表明:受纬度和地形影响,全国热量资源变化幅度较大,东部地区≥0℃、≥10℃积温随纬度变化呈阶梯状分布,而在西部地区主要受海拔影响,总体表现为由南向北逐渐递减。各地≥0℃和≥10℃积温范围分别为700.0~8960.0℃·d和46.3~8960.0℃·d,≥0℃和≥10℃积温气候倾向率平均为72.8℃·d·10a^(-1)和73.7℃·d·10a^(-1)。60a内,界限温度0℃、10℃初日分别提前9.6d和8.4d,终日分别推迟4.8d和7.8d。界限温度初日的提前和终日推迟使60a内日平均气温≥0℃和≥10℃的持续日数分别增加14.4d和16.2d。2011-2020年是研究时段内最温暖10a,与P1时段(1961-1970年)相比,P6时段(2011-2020年)≥0℃和≥10℃积温平均值分别增加了6.3%和8.2%。P6时段≥0℃积温为6000~7000℃·d的区域面积增加了2.11×10^(5)km^(2);≥10℃积温为5000~6000℃·d的区域面积增加了3.37×10^(5)km^(2)。气候变暖背景下,活动积温增加对农业系统产生了重要影响,农业生产布局以及种植制度应及时做出调整,充分适应气候变化。 展开更多
关键词 气候变化 热量资源 界限温度 活动积温
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