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λ-Red重组技术结合复合诱变提高大肠杆菌L-异亮氨酸合成能力
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作者 汪吉鹏 朱滕滕 +4 位作者 刘璐 马铖 魏晓博 刘慧燕 方海田 《食品工业科技》 北大核心 2025年第2期167-174,共8页
本研究旨在通过λ-Red重组技术结合复合诱变方法提高大肠杆菌L-异亮氨酸合成能力。以E. coli NXA为出发菌株,首先采用λ-Red同源重组敲除编码支链氨基酸转运蛋白基因brnQ,获得突变菌株E. coli NXA1。然后将E. coli NXA1经常温常压等离子... 本研究旨在通过λ-Red重组技术结合复合诱变方法提高大肠杆菌L-异亮氨酸合成能力。以E. coli NXA为出发菌株,首先采用λ-Red同源重组敲除编码支链氨基酸转运蛋白基因brnQ,获得突变菌株E. coli NXA1。然后将E. coli NXA1经常温常压等离子体(ARTP)、紫外(UV)与亚硝基胍(NTG)多轮复合诱变,以α-氨基丁酸(α-AB)为结构类似物进行筛选,筛选得到突变菌株E. coli NXA2。摇瓶发酵结果表明,在37℃、200 r/min条件下发酵40 h后,E. coli NXA1的L-异亮氨酸滴度为2.76 g/L,较E. coli NXA提高了33.98%;E. coli NXA2的L-异亮氨酸滴度为3.22 g/L,较E. coli NXA1提高了16.67%,较E. coli NXA提高了56.31%。对菌株E. coli NXA2经连续传代20代后,表现出较好的遗传稳定性。λ-Red重组技术结合复合诱变对大肠杆菌提高L-异亮氨酸合成能力有明显效果,为选育L-异亮氨酸高产菌株奠定理论基础。 展开更多
关键词 大肠杆菌 λ-red重组技术 brnQ基因 复合诱变 发酵 L-异亮氨酸
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Historical, Economical and Environmental Impacts of Suez Canal Connecting the Mediterranean Sea and Red Sea
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作者 Kenneth R. Olson Sergey S. Chernyanskii 《Journal of Water Resource and Protection》 2025年第2期68-95,共28页
The Suez Canal is a unique sea-level waterway between northern Africa and southern Asia that connects the Mediterranean Sea to the Red Sea via the Isthmus of Suez. The canal’s artificial navigation route substantiall... The Suez Canal is a unique sea-level waterway between northern Africa and southern Asia that connects the Mediterranean Sea to the Red Sea via the Isthmus of Suez. The canal’s artificial navigation route substantially reduced the sailing distance between countries in Europe and East Asia and offered a more direct route between the North Atlantic Ocean and the Indian Ocean through the Mediterranean Sea and the Red Sea. The primary objective of this study is to document the historical, economical, and environmental impacts of connecting the Mediterranean Sea and the Red Sea via a canal. After the completion of the Suez Canal in 1869 the canal became an economically lifeline for Egypt. However, the economic gains were partially offset by negative environmental impacts. The impact of port activities on the environment depends on their cargo volume and location, seaports can have an impact on the air quality and therefore on the health of the communities along the Suez Canal. The salinity barrier to migration was removed and animals and plants from the Red Sea began colonizing the eastern Mediterranean. Since the 1880s, species from the Indo-Pacific Ocean have been introduced, via the canal, into the Mediterranean ecosystem. They are endangering some local and endemic species and impacting the ecology. The results showed significant changes in the shoreline and land cover due to climate change and anthropogenic activities that necessitate the implementation of adequate protective measures. The findings of this study may assist policymakers in formulating adaptation plans to protect this crucial area, the communities along the Suez Canal and the Red Sea and Mediterranean ports, from climate change and human activities. 展开更多
关键词 Suez Canal EGYPT Mediterranean Sea red Sea
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基于Node-red的云端智能生产线控制系统设计与实现 被引量:1
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作者 陈玄烨 张鑫 +2 位作者 张景翔 文世华 李红利 《山东工业技术》 2024年第3期58-62,共5页
针对传统生产线在刚性生产过程中面临的成本过高、远程实施难、兼容性低等关键问题,基于目前中小企业的技术基础相对薄弱,无法将云计算平台、数据存储和处理等设备及技术运用到实际生产中的现状,本文利用西门子S7-1200 PLC作为核心控制... 针对传统生产线在刚性生产过程中面临的成本过高、远程实施难、兼容性低等关键问题,基于目前中小企业的技术基础相对薄弱,无法将云计算平台、数据存储和处理等设备及技术运用到实际生产中的现状,本文利用西门子S7-1200 PLC作为核心控制器,基于Node-red平台设计了成本低、兼容性高的云端智能生产线监控系统,便于实现对于生产线的监视和控制,提高生产效率与产品质量。现场运行表明,该系统运行稳定,满足智能生产线的设计要求,同时具备部署成本低、兼容性高的突出优势。 展开更多
关键词 工业物联网 Node-red 智能生产线 云端控制系统
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基于Node-RED的基建现场微气象监测与告警系统设计与实现 被引量:1
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作者 李瑞喜 何锐 +1 位作者 辛卫东 张博 《科学技术创新》 2024年第2期119-122,共4页
为了更好地满足输变电工程基建现场应用中对现场环境数据监测与告警的需求,本文设计实现了一种基于Node-RED的基建现场微气象监测与告警系统。该系统通过搭建基于Node-RED的监测预警服务,能够快速完成设备接入,实时监测PM2.5等各项微气... 为了更好地满足输变电工程基建现场应用中对现场环境数据监测与告警的需求,本文设计实现了一种基于Node-RED的基建现场微气象监测与告警系统。该系统通过搭建基于Node-RED的监测预警服务,能够快速完成设备接入,实时监测PM2.5等各项微气象指标,并且能够通过自动执行预设的处置策略就地进行告警或将数据推送至相关平台。该系统可以有效提升基建现场环境监测与告警的效率,在推进电力基建领域的数字化、智能化转型方面具有显著意义。 展开更多
关键词 Node-red 变电工程 基建现场 监测告警
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Red/ET同源重组介导的基因克隆载体pBACS的构建、鉴定与应用
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作者 侯少阳 李岚芳 +5 位作者 杜丽霞 孙林慧 李典 禚惠荣 姜莉莉 张大虎 《沈阳药科大学学报》 CAS CSCD 2024年第5期590-597,共8页
目的通过Red/ET同源重组技术构建pBACS基因克隆及测序质粒载体。方法以质粒pBAC2015、pET28a为模板设计四对引物,PCR扩增得到四段彼此间有50 bp同源区域的基因片段,分别命名为bac-sop、bac-ori、bac-kan和bac-T7。利用Red/ET同源重组技... 目的通过Red/ET同源重组技术构建pBACS基因克隆及测序质粒载体。方法以质粒pBAC2015、pET28a为模板设计四对引物,PCR扩增得到四段彼此间有50 bp同源区域的基因片段,分别命名为bac-sop、bac-ori、bac-kan和bac-T7。利用Red/ET同源重组技术,将四段基因片段电转至E.coli GB05-dir感受态中进行线线重组。经酶切、测序验证阳性克隆质粒。此外,对重组质粒pBACS进行稳定性鉴定;利用pBACS分别进行细菌16S rDNA和真菌ITS基因克隆和基因测序。结果酶切和测序的验证结果显示,质粒的大小、元件方向及序列正确;pBACS具有较强的稳定性,适用于作为基因工程的克隆载体;可高效用于细菌16S rDNA和真菌ITS序列的克隆,阳性率为100%。结论成功利用Red/ET技术构建克隆载体pBACS,质粒载体具有稳定性强、重组效率高的特点,在基因克隆和基因测序等方面具有良好的应用潜力。 展开更多
关键词 pBACS 克隆 red/ET技术 同源重组
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优化逆序发生率的RED-TOPSIS模型
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作者 陈勇明 谢照敏 郭弘 《调研世界》 CSSCI 2024年第1期51-66,共16页
为解决TOPSIS模型中存在的逆序问题,本文提出一种基于纪录值的TOPSIS模型,称为RED-TOPSIS模型,该模型针对有纪录值数据的多属性决策问题,采用区间化公式或最大最小化公式作无量纲化处理,利用纪录值构造理想解。由于纪录客观存在且有不... 为解决TOPSIS模型中存在的逆序问题,本文提出一种基于纪录值的TOPSIS模型,称为RED-TOPSIS模型,该模型针对有纪录值数据的多属性决策问题,采用区间化公式或最大最小化公式作无量纲化处理,利用纪录值构造理想解。由于纪录客观存在且有不易打破的特点,以此确定的理想解具有近似于绝对理想解的稳定性兼具相对理想解的客观性,使得RED-TOPSIS模型理论上仅当纪录被打破时才可能产生逆序,从而在实际应用中易于操作且能大幅降低逆序现象的发生。 展开更多
关键词 多属性决策 TOPSIS模型 逆序 red-TOPSIS模型
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Using Optical Tweezers to Study the Friction of the Red Blood Cells
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作者 Edoukoua Jean Michel Konin Pavel Yale +3 位作者 Abadê Ange-Boris N’guessan Kouassi Benoit Kouakou Abaka Michel Kouacou Eugene Megnassan 《Advances in Bioscience and Biotechnology》 CAS 2024年第2期100-111,共12页
In the last two decades the study of red blood cell elasticity using optical tweezers has known a rise appearing in the scientific research with regard to the various works carried out. Despite the various work done, ... In the last two decades the study of red blood cell elasticity using optical tweezers has known a rise appearing in the scientific research with regard to the various works carried out. Despite the various work done, no study has been done so far to study the influence of friction on the red blood cell indentation response using optical tweezers. In this study, we have developed a new approach to determine the coefficient of friction as well as the frictional forces of the red blood cell. This approach therefore allowed us to simultaneously carry out the indentation and traction test, which allowed us to extract the interfacial properties of the microbead red blood cell couple, among other things, the friction coefficient. This property would be extremely important to investigate the survival and mechanical features of cells, which will be of great physiological and pathological significance. But taking into account the hypothesis of friction as defined by the isotropic Coulomb law. The experiment performed for this purpose is the Brinell Hardness Test (DB). 展开更多
关键词 FRICTION INDENTATION Optical Tweezers TRIBOLOGY red Blood Cells
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Analysis and Assessment on the Heavy Metals in a Severely Degraded Subtropical Red Soil Region
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作者 Fang Wang Yun Zhou +5 位作者 Xiangping Fu Yuxiao Zhao Yiyao Wen Xintao Cui Shunbao Lu Yanjie Zhang 《American Journal of Plant Sciences》 CAS 2024年第2期110-121,共12页
5 different forests of Pinus massoniana, Schima superba, Liquidambar formosana, P. massoniana × S. superba, P. massoniana × L. formosana as the research object were set up to study the Cr, Cu and Zn content ... 5 different forests of Pinus massoniana, Schima superba, Liquidambar formosana, P. massoniana × S. superba, P. massoniana × L. formosana as the research object were set up to study the Cr, Cu and Zn content of degraded red soil region in subtropics. The soil heavy metal pollution degree was evaluated by national environmental quality standard (II class). The results showed that three soil metals of P. massoniana × S. superba were the highest, and the soil metals enrichment ability was strong. The order of single factor pollution index of metal elements was Cu (1.38) > Cr (0.81) > Zn (0.42), and moderately pollution, pollution warning and no pollution, respectively. There was no significant correlation between three soil heavy metals and soil total carbon (TC), total nitrogen (TN) and total phosphorus (TP). These results suggested that the accumulation of heavy metal elements was not derived from the parent material of soil. There was a significant positive correlation between the three metal elements which indicated that the sources of the three elements were similar. The structural equation model showed that the direct and indirect effects among the influencing factors ultimately affected the activity of heavy metals by cascade effects. 展开更多
关键词 Subtropical Forest Type Degraded red Soil Heavy Metals Pollution Evaluation
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Diversity, Abundance and Distribution Patterns of Epibenthic Echinoderms in Dungonab Bay, Red Sea, Sudan
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作者 Abdelmoneim Karamalla Gaiballa 《Open Journal of Ecology》 2024年第4期366-380,共15页
The abundance, distribution and diversity of epibenthic echinoderm were investigated at Dungonab Bay in the Red Sea coastal water of the Sudan. Four permanent line transects were chosen. Eight (30 × 2) square met... The abundance, distribution and diversity of epibenthic echinoderm were investigated at Dungonab Bay in the Red Sea coastal water of the Sudan. Four permanent line transects were chosen. Eight (30 × 2) square metre belt transects along each permanent line transect at 20 metre intervals were used to collect data. The data were subjected to univariate and multivariate analyses. Spatial variations of epibenthic echinoderm abundance were assessed with one-way analysis of variance. Hierarchical agglomerative clustering was used to identify and illustrate the similarities in echinoderm abundance between line transects and between belt transects. Indices of richness (d), diversity (H'), evenness (J') and dominance (C) were used to explain the diversity of epibenthic echinoderm species. The distribution pattern of each echinoderm species was determined in each permanent line transect. A total of 986 individuals were recorded within sixteen species of epibenthic echinoderms in the four line transects. Holothuriidae was the dominant family (5 species and 342 individuals). The most abundant echinoderms species was Pearsonothuria graeffei (77 individuals, about 7.81%). Abundances intra-transects and intra-families were insignificant (f = 1.67, p = 0.183, df = 3 and f = 3.24, p = 0.083, df = 9, respectively). The highest values of Shannon-Wiener diversity index (H'), Pielou evenness index (J'), Margalef species richness index (d), and Simpson Dominance index (C) were 2.738, 0.9875, 2.791 and 0.07159, respectively. The distribution patterns of all species in the study transects varied between clumped and uniform, with the exception of Asthenosoma varium of the Echinothuridae family, which had clumped distribution patterns in all transects. The study concluded that Dungonab Bay supports rich and diverse communities of epibenthic echinoderms. 展开更多
关键词 SUDAN red Sea ECHINODERM DIVERSITY Abundance and Distribution
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基于物联网平台Node-RED设计开发的鱼菜共生系统
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作者 皇甫开心 陶思棋 +2 位作者 刘春新 王祎玮 李宗轩 《农机使用与维修》 2024年第11期20-23,共4页
基于物联网平台Node-RED设计了一款鱼菜共生系统。通过图文介绍该系统总体设计思路以及硬件选型方向和软件设计方法。用硬件树莓派、传感器等,软件Node-RED、MQTT等建立一套远程观察检测系统,并实现鱼菜共生循环。此系统还可以拓展应用... 基于物联网平台Node-RED设计了一款鱼菜共生系统。通过图文介绍该系统总体设计思路以及硬件选型方向和软件设计方法。用硬件树莓派、传感器等,软件Node-RED、MQTT等建立一套远程观察检测系统,并实现鱼菜共生循环。此系统还可以拓展应用于智能家居,其成本低廉,操作简单,适宜大规模推广,有一定市场价值。 展开更多
关键词 鱼菜共生 Node-red 树莓派 MQTT 垂直农场
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基于PLC和Node-RED的远程油箱液位监控与邮件报警控制系统设计
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作者 徐光辉 樊晓宇 《佳木斯大学学报(自然科学版)》 CAS 2024年第8期80-82,共3页
主要介绍了如何使用Node-RED与西门子S7-1515 PLC通过S7通讯方式,实现油箱液位远程监控与邮件报警功能。首先介绍了Node-RED和西门子S7-1515 PLC的相关技术,然后详细阐述了系统的设计与实现过程,最后对系统进行了测试与应用。该系统的... 主要介绍了如何使用Node-RED与西门子S7-1515 PLC通过S7通讯方式,实现油箱液位远程监控与邮件报警功能。首先介绍了Node-RED和西门子S7-1515 PLC的相关技术,然后详细阐述了系统的设计与实现过程,最后对系统进行了测试与应用。该系统的成功应用为工业自动化领域提供了一个有效的解决方案,能够实时监控油箱液位,并在超出预设范围时及时发送报警邮件,提高了生产安全和效率。 展开更多
关键词 Node-red 西门子S7-1515 PLC 油箱液位 远程监控 邮件报警
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Importance of Stewards and Other Protection Efforts for Conservation of Red Knots (Calidris canutus rufa) and Other Shorebirds on Delaware Bay, New Jersey
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作者 Joanna Burger Amanda Dey Larry Niles 《Natural Science》 2024年第9期162-182,共21页
Understanding the factors that contribute to population stability in long-distance migrant birds is increasingly important, particularly given global climate change, sea level rise, and loss or disturbance at essentia... Understanding the factors that contribute to population stability in long-distance migrant birds is increasingly important, particularly given global climate change, sea level rise, and loss or disturbance at essential habitats. While the populations of most shorebirds are declining worldwide, those that migrate through Delaware Bay, New Jersey and Delaware, are declining at the most rapid rate despite conservation efforts. In this paper, we 1) provide background information on population declines of red knots (Calidris canutus rufa) using Delaware Bay, threats to their foraging, and efforts to reduce threats, 2) summarize briefly our studies of the effects of human activities on knots and other shorebirds, 3) present data on management efforts to protect knots and other shorebirds from the activities of people, and 4) discuss the efficacy of such efforts (usually referred to as “decreasing the effect of human disturbances”). The Shorebird Project on Delaware Bay is over 25 years old and provides long-term data to help assess the status of shorebird numbers, particularly for red knot, as well as the density of horseshoe crabs (Limulus polyphemus) and their eggs. Red knots have continued to decline even more precipitously in the last few years, presenting cause for concern. Protective efforts have been successful in reducing human disruption on the N.J. Delaware Bay beaches, but the lack of uniformity in implementation across the New Jersey side, and across the whole Bay have hampered further improvements. Implementation of signs, fencing, and stewards on some beaches significantly enhanced the use of these beaches by red knots, determined by examining the use of beaches pre- and post-implementation. Implementation of fencing and stewards had the greatest effect. From 1986 to 2018, there was a significant shift in the percent of Delaware Bay red knots using the NJ side, where protection efforts had been implemented on many of the beaches. Merely restricting access (without fencing or other efforts) did not result in more knots using the beaches post-restriction. This is the first paper that clearly shows the protective effects of having beach stewards. We discuss the long-term needs for continued management of Delaware Bay beaches, and other beaches coastwide, and of determining the causes of population declines of red knots. 展开更多
关键词 red Knot Calidris canutus rufa CONSERVATION Beach Monitors Human Disturbance Habitat Restoration Management Stewards Education Population Declines Coastal
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Python和Node-Red在整车制造工厂能源数据采集与企业能源管理中的应用
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作者 刘德昊 彭松 +1 位作者 王恺 刘放 《自动化应用》 2024年第14期280-283,共4页
面对日益严格的节能环保标准,汽车制造企业必须精细化监控生产设备的能源消耗。以北京奔驰顺义工厂为例,展示了一种基于Python和Node-Red的自动能耗数据采集和上传系统。该系统首先利用Node-Red实时获取车间内各设备PLC的电能和燃气消... 面对日益严格的节能环保标准,汽车制造企业必须精细化监控生产设备的能源消耗。以北京奔驰顺义工厂为例,展示了一种基于Python和Node-Red的自动能耗数据采集和上传系统。该系统首先利用Node-Red实时获取车间内各设备PLC的电能和燃气消耗数据并存至数据库中,其次通过Python将数据整合并存入Excel,最后在计算近2日的能耗差值后,将其上传至企业能源论坛。若数据提取或上传出现异常,系统则会自动发送邮件提醒用户。目前,该系统已成功应用于喷漆车间和总装车间的电能数据自动获取和上传,监控的数据类型也将扩展至包括用水量、蒸汽用量、压缩气用量等在内的各类能源消耗。通过该方式,汽车制造企业能更有效地满足节能环保要求,为可持续发展作贡献。此外,该系统的应用进一步凸显了Python和Node-Red在能源管理中的关键作用,为汽车制造业的能源管理提供了新的视角和工具。 展开更多
关键词 Node-red PLC PYTHON 能源管理 车间数字化
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特早熟红肉油桃优系“4-86-2”选育初报
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作者 王富荣 黄小平 +12 位作者 艾小艳 王会良 刘勇 朱炜 张杨 甘志猛 顾霞 刘模发 诸小敏 黎刚 吴文鹏 何华平 龚林忠 《中国南方果树》 北大核心 2025年第1期200-203,共4页
“4-86-2”桃是以“枣油桃”为母本,“早仙红”为父本杂交而成的特早熟红肉油桃优系。该优系树势较强,树姿半开张;在武汉地区始花期3月中旬,果实成熟期5月中旬;花蔷薇型,花粉可育,果实近圆形,平均单果质量80~100 g,最大146 g;果面光滑无... “4-86-2”桃是以“枣油桃”为母本,“早仙红”为父本杂交而成的特早熟红肉油桃优系。该优系树势较强,树姿半开张;在武汉地区始花期3月中旬,果实成熟期5月中旬;花蔷薇型,花粉可育,果实近圆形,平均单果质量80~100 g,最大146 g;果面光滑无毛,果皮、果肉均呈鲜红色,完熟时暗红色,花青素含量高达151.67 mg/kg;黏核,肉质硬溶质,较耐贮运;风味浓甜,可溶性固形物含量10%~12%,可滴定酸含量0.19%~0.24%;3~4年进入盛果期,平均产量18.0 t/hm^(2)。 展开更多
关键词 红肉桃 油桃 特早熟 栽培技术
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中熟红皮梨新品种灿玉的选育
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作者 李龙飞 高丽娟 +4 位作者 徐金涛 冀明辉 刘欢 曾庆明 郝宝锋 《果树学报》 北大核心 2025年第3期668-671,共4页
灿玉是红茄梨自然杂交选育的优质鲜食中熟红皮梨新品种。平均单果质量325.1 g,粗颈葫芦形,果皮底色黄绿色,盖色橘红,果心小,无籽,可食率高,果肉乳白色,软溶,肉质细腻多汁,风味酸甜、香,可溶性固形物含量(w)为14.5%,鲜食品质上等。树势强... 灿玉是红茄梨自然杂交选育的优质鲜食中熟红皮梨新品种。平均单果质量325.1 g,粗颈葫芦形,果皮底色黄绿色,盖色橘红,果心小,无籽,可食率高,果肉乳白色,软溶,肉质细腻多汁,风味酸甜、香,可溶性固形物含量(w)为14.5%,鲜食品质上等。树势强,成枝力、萌芽力强,树姿开张,1年生枝向阳面主要颜色为赤黄色。叶缘锐锯齿,叶尖长渐尖。花芽较易形成,早果丰产性好,适宜纺锤形栽培。在河北昌黎地区3月中旬花芽开始萌动,8月中旬果实成熟,果实发育期约120 d。适宜在河北昌黎、曹妃甸、泊头及相似生态区种植。 展开更多
关键词 新品种 灿玉 中熟 红皮
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干湿循环下石灰改良红层泥岩填料力学性能劣化规律研究
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作者 陈康 刘先峰 +3 位作者 蒋关鲁 袁胜洋 马杰 陈忆涵 《岩土力学》 北大核心 2025年第1期43-54,共12页
红层泥岩水敏性高,作路基填料时可用石灰改良。受季节变化影响,路基基床经历干湿循环,导致服役性能降低。为研究干湿循环下改良填料力学特性劣化规律,开展一系列干湿循环试验、无侧限抗压试验和弯曲元试验测定改良填料无侧限抗压强度和... 红层泥岩水敏性高,作路基填料时可用石灰改良。受季节变化影响,路基基床经历干湿循环,导致服役性能降低。为研究干湿循环下改良填料力学特性劣化规律,开展一系列干湿循环试验、无侧限抗压试验和弯曲元试验测定改良填料无侧限抗压强度和小应变刚度。结合连续滴水扫描电镜(scanning electron microscope,简称SEM)试验,揭示干湿循环后填料微观结构劣化特征。结果表明:低幅度循环下试样在干侧和湿侧均产生体胀。高幅度循环下试样在湿侧产生体胀。在干侧先产生体缩,随循环次数增加,即使含水率较低,试样也产生体胀。体胀导致强度和小应变刚度均有不同程度的劣化。当试样产生体缩时,强度有所增长,但小应变刚度由于裂缝衍生而持续衰减。试样强度随损伤体变可用统一劣化方程表示。但高幅度循环下试样干燥后的小应变刚度远低于劣化线,且劣化速率远大于强度。试样滴水后能维持基本形貌,但观察到团聚体松散、微粒剥落和新生裂缝等结构劣化特征,从而导致宏观力学性能衰减。 展开更多
关键词 路基填料 干湿循环 石灰改良 红层泥岩 性能劣化
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国家卫生健康行业标准《儿科输血指南》造血干细胞移植患儿输血的编制说明与解读
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作者 黄蓉 何庆南 +17 位作者 黑明燕 竺晓凡 卢俊 徐晓军 袁天明 张蓉 王旭 刘晋萍 王静 邵智利 赵明一 郭永建 吴心音 陈佳睿 陈琦蓉 郭佳 桂嵘 杨明华 《中国当代儿科杂志》 北大核心 2025年第2期139-143,共5页
为了指导儿童患者的临床输血实践,国家卫生健康委员会发布了卫生健康行业标准《儿科输血指南》(WS/T 795-2022)。造血干细胞移植患儿输血极具复杂性和挑战性,该指南对这些患儿的输血阈值、血液成分的选择给出了指导和建议。该文将介绍... 为了指导儿童患者的临床输血实践,国家卫生健康委员会发布了卫生健康行业标准《儿科输血指南》(WS/T 795-2022)。造血干细胞移植患儿输血极具复杂性和挑战性,该指南对这些患儿的输血阈值、血液成分的选择给出了指导和建议。该文将介绍造血干细胞移植患儿输血条款内容的证据与解读,希望对《儿科输血指南》的理解和贯彻实施有所助益。 展开更多
关键词 造血干细胞移植 红细胞输注 血小板输注 儿童
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Development of Non-ABO Red Blood Cell Alloantibodies in Patient Undergoing Allogeneic Haematopoietic Stem Cell Transplant
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作者 Ahmed Alsuhaibani Khalid Batarfi +14 位作者 Ahmed Alharbi Haya Alwasel Abdullah Alenazi Abdulmohsen Alotaibi Jalal Hassan Rayyan Alotaibi Hajer Aziz Nourah Alharethi Sara Alobaidi Maram Alonayzan Sanad Alharthi Majd Alanazi Sarah Alotaibi Ahmed Shareefi Bandar Alqahtani 《Case Reports in Clinical Medicine》 2024年第5期162-170,共9页
Alloantibodies that are non ABO Alloimmunization to protein antigens happens only after exposure, in contrast to ABO isohaemagglutinins, which are present naturally, even in the absence of prior exposure. It is recogn... Alloantibodies that are non ABO Alloimmunization to protein antigens happens only after exposure, in contrast to ABO isohaemagglutinins, which are present naturally, even in the absence of prior exposure. It is recognized that while non-ABO RBC antibodies are less common than ABO antibodies, they generate essentially the same issues that lead to unfavorable clinical results. If non-ABO alloantibodies are identified early on, these issues related complications may be avoided This call for an in-depth understanding of the recipient and donor’s ABO-Rh grouping, antibody screening, and the phenotype of certain antigens. Equally important, the temporal association time between transplantation and hemolysis can help identify the underlying mechanism of hemolysis and direct appropriate management. Therefore, for that, it is crucial to identify the etiology of post-HSCT anemia for prevention and therapy, in addition to a thorough grasp of the mechanism of anemia in non-ABO-incompatible HSCT and the temporal link between HSCT and anemia. Finding the cause of post-HSCT anemia is essential for prevention and therapy, in addition to a thorough grasp of the mechanism of anemia in non-ABO-incompatible HSCT and the temporal link between HSCT and anemia. Therefore, for that, it is crucial to identify the etiology of post-HSCT anemia. In this case report review, we would like to highlight the vital role of transfusion medicine services and stem cell clinical teams in paying particular attention to the clinical significance of non-ABO alloantibodies involved to avoid causing overt hemolysis of incompatible donor RBCs or delayed erythropoiesis. Considering the fact that some of the Haematopoietic stem cell transplant centers do not give an attention to the other non-ABO RBC antigens. 展开更多
关键词 Haematopoietic Stem Cell Transplant (HSCT) Non-ABO red Blood Cell Antibodies ALLOANTIBODIES
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桂北苗儿山铀矿田铀源分析:来自周缘红盆碎屑锆石的制约
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作者 谭双 刘晓东 +5 位作者 雷勇亮 陈琪 万建军 吴昆明 欧阳平宁 黄宏业 《大地构造与成矿学》 北大核心 2025年第1期70-84,I0006-I0010,共20页
花岗岩型热液铀矿床铀源的认识目前存在一定分歧,部分观点认为铀矿床周缘红盆可能提供成矿物质来源。苗儿山铀矿田是华南地区典型的花岗岩型铀矿田之一,但关于周缘红盆与铀矿床之间的关系尚未开展过系统研究。本次研究选取苗儿山地区红... 花岗岩型热液铀矿床铀源的认识目前存在一定分歧,部分观点认为铀矿床周缘红盆可能提供成矿物质来源。苗儿山铀矿田是华南地区典型的花岗岩型铀矿田之一,但关于周缘红盆与铀矿床之间的关系尚未开展过系统研究。本次研究选取苗儿山地区红盆内的碎屑岩为研究对象,对其开展岩相学、碎屑锆石U-Pb年代学和地球化学研究,旨在限定碎屑岩的形成时代上限和物质来源,进而探讨区内铀矿床的铀源问题。锆石CL图像和稀土元素分布特征显示,研究区内碎屑岩的锆石为岩浆锆石, LA-ICP-MS锆石U-Pb年龄为416~2485 Ma,主要峰值集中在721~839 Ma和416~436 Ma,与苗儿山铀矿田晋宁期和加里东期构造-岩浆热事件时间一致。锆石元素面扫描图像特征显示,其具有较强的流体交代痕迹,U元素存在明显的活化迁移行为,记录了一定程度的蚀变改造或矿物溶解沉淀过程。通过系统收集苗儿山铀矿田及其周边侵入岩的年代学数据并进行对比分析,认为721~839 Ma的碎屑锆石可能主要来自苗儿山地区花岗岩和湖南城步地区新元古代花岗岩;而416~436 Ma的锆石主要来自越城岭-苗儿山加里东期复式花岗岩基。结合前人研究,认为苗儿山铀矿田中的部分铀源可能来自区内新资断陷红盆碎屑岩,富含CO_(2)等矿化剂的幔源流体沿着深大断裂上升与循环的地下水结合形成热液,与富铀花岗岩、红盆碎屑岩等相互作用,进而形成富铀的成矿流体。 展开更多
关键词 新资断陷红盆 苗儿山铀矿田 碎屑锆石 年代学 稀土元素 铀源
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福建客家“红菌豆渣”微波真空干燥技术研究
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作者 黎英 蔡源昊 +3 位作者 赵金花 杨彩凤 林标声 陈小红 《中国调味品》 北大核心 2025年第2期180-186,共7页
为解决发酵后“红菌豆渣”存在的菌丝塌陷、老化和水分含量高等问题,同时获得品质较好的干制品,以“红菌豆渣”为对象开展了微波真空干燥研究,通过测试不同微波功率密度、真空度、切片厚度条件下“红菌豆渣”的平均干燥速率、色差值和... 为解决发酵后“红菌豆渣”存在的菌丝塌陷、老化和水分含量高等问题,同时获得品质较好的干制品,以“红菌豆渣”为对象开展了微波真空干燥研究,通过测试不同微波功率密度、真空度、切片厚度条件下“红菌豆渣”的平均干燥速率、色差值和复水率,并借助多元回归数学模型对工艺参数进行优化。结果表明,在50℃条件下,其最优干燥条件为微波功率密度53 W/g、真空度-0.05 MPa、切片厚度9 mm,此时平均干燥速率为(3.27±0.29)%/min,“红菌豆渣”的色泽与鲜样的差异ΔE为2.61±0.31,复水比为5.19±0.23;扫描电镜下其质构较好且内部空隙较均匀。该工艺既提高了“红菌豆渣”的干燥效率和品质,又为“红菌豆渣”的产业化生产提供了参考。 展开更多
关键词 微波真空干燥 红菌豆渣 工艺优化 干燥特性 微观结构
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