mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
强烈免疫抑制联合脐血输注治疗重型再生障碍性贫血25例临床观察

SAA-I病情凶险,死亡率高,虽然指南中指出SAA宜及早行HLA匹配同胞供体的异基因骨髓移植(allo-BMT),但由于我国国情限制,同胞供者难以寻找,因此大剂量免疫抑制剂治疗在SAA治疗中占重要地位. 免疫抑制治疗常见药物为CsA、CTX、ATG/ALG等,ATG联合CsA是目前治疗SAA的标准方案,有效率为70%- 80%,其疗效优于单独应用~[2]. 文献报道大剂量CTX(40-50 mg/kg,连用4d)治疗SAA,患者外周血ANC达到0.5×10~9/L的平均时间为54(35 - 119) d,总有效率为40%- 70%,且大剂量CTX的不良反应----出血性膀胱炎也不容忽视. 目前免疫抑制治疗失败的原因主要包括:①免疫抑制剂(特别是ATG)剂量不足,不能充分实现其免疫抑制与免疫刺激的联合效应;②HSC储备耗竭,即使解除异常免疫,残存HSC亦不能重建造血;③非免疫因素导致骨髓造血功能衰竭,如Fanconi贫血、先天性角化不良症等先天性骨髓衰竭综合征;④诊断性偏差~[2]. 陈纯等~[3]回顾性分析31例儿童SAA患者,应用CsA联合ATG强化免疫抑制治疗,起效平均时间为2.5(1 -5)个月,有效率为81%,主要死亡原因为严重感染. 郑以州等~[4]采用前瞻性同期对照研究方法,比较ALG单独应用或联合CsA(强化免疫抑制治疗,IIST)治疗SAA的疗效,其中IIST的43例患者中24例 (55.8%)达到基本治愈,缓解6例(14.0%),明显进步6例 (14.0%),无效7例(16.3%),总有效率为83. 7%. 14例 (32.6%)发生严重感染,感染相关死亡3例(7.0%). 美国国立卫生研究院(NIH)以ATG+CsA治疗51例SAA患者,3个月和12个月的有效率分别为67%和78%,1年和2年实际生存率为86%和72%~[5-6]
基于淫羊藿苷测定及HPLC指纹图谱分析的淫羊藿药材质量差异评价

目的建立客观评价淫羊藿药材质量差异的方法.方法采用高效液相色谱法, Kromasil C18柱(250 mm×4.6 mm,5μm),流动相为乙腈-水(23:77),体积流量1 mL/min,检测波长270 nm,进样量10μL,建立不同产地,不同品种淫羊藿药材不同生长部位(茎与叶)的HPLC指纹图谱,并测定其不同生长部位中淫羊藿苷的量.结果 淫羊藿药材不同生长部位(茎与叶)的HPLC指纹图谱和淫羊藿苷的量存在差异,从其叶和茎的特征指纹图谱中分别提取出19和10个共有峰,且叶中淫羊藿苷的量是茎中的48倍;叶与叶,茎与茎之间的化学特征存在差异,叶与茎化学特征差异最显著.结论建立的淫羊藿苷测定方法和指纹图谱的精密度,稳定性,重现性好,可表征淫羊藿药材质量的差异性,为淫羊藿药材的质量研究和建立淫羊藿药材的商品规格提供参考依据
基于企业能力的商誉计量方法研究

本文认为能力是商誉的内在支撑,商誉是能力的外在表现,其价值是可以降低市场交易双方的风险和成本.根据商誉与能力的内在联系,可通过对能力进行评价,实现对商誉计量的目标.并提出基于能力的商誉指数和商誉价值计量方法
后金融危机时期企业财务活力提升的有效途径

2007年夏季爆发的金融危机导致全球经济遭到重创,经济增长明显放缓,全球市场动荡加剧,资产价格大幅缩水;自2009年6月,世界经济回暖初见端倪,并在缓慢波动中复苏,种种迹象表明"后金融危机时期"已经来临.在此背景下,要使企业尽快恢复活力并取得新的发展机会,笔者认为,必须从提高企业核心竞争力这一基础环节入手,而提高企业核心竞争力的关键就在于提升企业财务活力,即提升企业资源利用、技术与管理创新和处理本金投入与收益活动及其财务关系的能力.鉴于此,本文从发展方式、市场资源、公司治理和企业创新能力等方面探讨了后金融危机时期企业财务活力提升的有效途径
多委托人框架下的电力产业监管模型研究

电力产业的监管涉及多个监管者.研究发现,监管者不合作情况下的整体监管效果要差于合作的情况,并且监管者决策顺序的差异也会对电力监管的效果产生影响.鉴于监管者不会自动达到合作状态,建议设立一个高级别的组织,对电力监管中的多个监管者进行协调,提高电力监管的整体效果
不同元素品牌联合模式下的主品牌联合效应研究冰

本文研究了不同元素品牌联合模式下的主品牌联合效应以及元素品牌的知名度、元素在主品牌产品属性中的地位、主品牌的知名度对主品牌联合效应的影响,并使用消费者归因选择数据对结论进行了检验.基于3个前测和一个来自北京市4 36位消费者的正式调研数据,我们发现:(1)不同联合模式下主品牌获得的联合效应不同且在感知质量维度显著高于购买意愿维度;(2)元素品牌知名度越高,主品牌获得的联合效应越大;(3)知名元素在主品牌中的地位越重要,主品牌感知质量的提升幅度越高;(4)主品牌的知名度越高,其获得的联合效应越小;(5)影响联合品牌属性优化的3大因素依次为:知名主品牌、知名元素品牌和联合匹配性
风沙干旱区紫花苜蓿大面积高产栽培技术

紫花苜蓿是世界上最重要的豆科牧草,兼有"牧草之王"的美誉,不仅营养价值高,适口性好,而且具有很强的改土培肥,蓄水和保持生态平衡的能力,是发展人工草地的优质牧草品种,同时也是发展畜牧业,调整农业种植结构的重要作物之一,在现代农业生产中受到普遍重视
江苏省高效设施茶业发展中存在的困难与对策

对江苏省发展高效设施茶业中存在的困难因素进行分析,针对性地提出江苏省高效设施茶业发展策略:加强高效设施茶叶生产基地的规模化;提高高效设施茶园的技术含量与水平;综合开发利用夏秋茶;推广全程清洁化,连续化的加工生产线;建设紧密型茶叶合作组织;加造强势品牌;建立并健全茶业科技创新服务机构与体系
我国梨果产业现状及发展战略研究

通过对我国梨果栽培面积,产量,区域化布局,品种结构和贸易现状的分析,指出我国梨果产业发展所面临的"瓶颈",提出加强产业引导,良种繁育体系建设,品牌建设,精品高效标准化生产,市场体系建设,技术培训,产业化经营和保障支撑等发展战略,为实现梨果产业可持续发展提供参考
2000--2008年邛海公园水质变化趋势

据2000--2008年邛海公园主要水质参数的实测资料,运用季节性肯达尔检验方法对邛海公园水质变化趋势进行分析,结果表明:邛海公园5 d生化需氧量(BOD5),溶解氧,粪大肠菌群和总磷都呈上升趋势;总氮呈下降趋势
红河州小米辣中矿物元素比较

用原子吸收光谱法测定了云南省红河州蒙自县,石屏县,屏边县和金平县的小米辣中矿物元素Ca,Mg,Fe,Zn,Cu,Co,Ni等的含量,相对标准偏差在0.43%1.86%之间,回收率在96.58%106.92%之间.结果表明: Mg含量最高的是屏边小米辣,为2 266.6μg/g;Ca,Fe,Co含量最高的是蒙自小米辣,分别为750.0,57.55,0.625 0μg/g;Zn,Cu,Ni含量最高的是金平小米辣,分别为15.70,15.18,1.875μg/g.Mg在测定的元素中含量最高,平均含量高达1 853.8μg/g,其次是Ca,平均含量为631.9μg/g, Fe平均含量为43.54μg/g,所测元素含量大小顺序为: Mg>Ca>Fe>Zn>Cu>Ni>Co.小米辣中含有人体必需的矿物元素Ca,Mg,Fe,Zn,Cu等
高油脂物料物性对其微细粉碎特性的影响

高油脂物料的微细粉碎十分困难,本研究从常见的一种高油脂物料----花生的物理性质着手分析其粉碎特性.对不同含水率的花生进行质构分析,从粉碎作用力学角度探讨花生物料较为合理的粉碎方式.认为通过适当降低原料含水量,强冷手段控制颗粒表面温升和采用有效粉碎作用力使颗粒局部受力等方法,使高油脂物料微细粉碎工艺得到改进,为深入研究高油脂物料的微细粉碎提供了试验依据和方法
几种植物净化能力的比较及浮床应用效果研究

以美人蕉等4种植物为材料,在温室内进行氮磷静态耗竭试验,筛选合适的浮床植物并研究组合浮床对巢湖池塘富营养化水体的改善效果.静态耗竭试验结果表明:除氮效果上,美人蕉仅次于水葫芦,但优于蕹菜和水芹;除磷效果上,美人蕉要优于水葫芦,蕹菜和水芹;综合比较植株生物量增重情况和根系发育状况,美人蕉更适合作为浮床植物.野外浮床试验结果表明:60 d的试验期内,组合浮床对池塘总氮净化率为79.2%,对总磷净化率为94.0%,叶绿素浓度比对照塘降低26.2%,每平方米组合浮床的净化能力为氮55.2 g,磷4.08 g,总氮,总磷的平均去除负荷为0.92 g/(m2.d)和0.068 g/(m2.d),浮床生态系统对巢湖水源地水质有明显的改善作用
13种农药在气相色谱仪分离过程中稳定性的差异分析

对13种农药在气相色谱仪分离过程中表现的稳定性差异进行了分析,发现同一浓度不同农药的RSD有很大差异.13种农药在浓度为0.10 mg/kg的条件下,多次进样得到的RSD和峰面积大小,极差值和保留时间没有明显相关性.13种农药在浓度为0.10 mg/kg时,农药在气相色谱仪分离过程中的稳定性与农药进样量以及特有化学性质等有关.要减少这方面误差最好的方法是尽量多次进样,去掉最大值和最小值,取平均值可能会更接近真值
江苏滩涂围垦区土壤养分空间变异研究

采用地理信息系统(GIS)和地统计方法,研究20世纪80年代初围垦王竹垦区的土壤养分空间变异特征.结果表明:有机质,碱解氮,全磷,速效磷块金基台比介于7.9%19%之间,表现出强烈的空间相关性;土壤pH值,全氮,全钾,速效钾的块金基台比值介于29.8%49.9%之间,表现出中等的空间相关性.土壤pH值,全氮,全磷,全钾的空间分布呈带状,以较大区域变异为主;碱解氮,速效钾的空间渐变性稍差,以中等大小区域变异为主;有机质,速效磷的空间分布呈团状,以较小区域变异为主.土壤各养分的空间分布图可直观表示出各养分的空间变异特征和丰歉程度,样区有机质含量处于中低水平,碱解氮含量极低,速效钾,速效磷含量较高.建议多施氮肥和有机肥,少施或不施钾肥和磷肥
长白山区野生桔梗与栽培桔梗主要农艺性状的变异比较

在对长白山区24个地点野生桔梗的生境和生长情况进行调查的基础上,采集野生桔梗种子种植在试验田,测定分析1年生野生桔梗的株高等8个主要农艺性状的变异范围,并与24份栽培桔梗进行比较.结果表明:现存的野生桔梗大多数生长在生境比较恶劣的地方,所以植株细小,根也较小;但种植在试验田的野生桔梗后代生长旺盛,株高等8个主要农艺性状的变异范围与栽培桔梗基本相似,说明野生桔梗与栽培桔梗之间还没有形成明显的差异,有的野生桔梗种质资源可以在桔梗生产中直接利用
不同预处理方法对模拟动态逆流提取灵芝多糖的影响

以灵芝为对象,研究了动态逆流结合预处理的提取方法,比较了一般浸润,真空微波,挤压,真空微波与挤压组合4种预处理方法对动态逆流提取灵芝多糖的影响.研究结果表明,4种预处理方法,灵芝多糖提取率由高到低的顺序为:真空微波+挤压>微波>挤压>一般浸润.其中真空微波+挤压预处理比一般的浸润处理灵芝多糖的提取率高23%
香菇生产中高效安全杀虫剂的筛选

以农业上广泛应用的植物杀虫剂为供试药物,采用平板加药法和杀虫剂杀灭菇蝇的试验,研究植物杀虫剂对香菇菌丝生长的影响和对菇蝇的杀灭效果.结果表明,不同药剂对香菇菌丝生长的影响和对菇蝇的防效存在显著差异,在低浓度下印楝素对菌丝生长的抑制作用较小,且对菇蝇的防效比高效氯氰菊酯好,可作为理想的高效安全杀虫剂在食用菌栽培中应用
海涂米草与水稻远缘杂交种质资源发掘与创新(Ⅱ)

为了发掘米草耐盐和水稻高产种质资源以创制耐盐水稻新种质,在2005--2007年开展的米草与水稻属间远缘杂交研究的基础上,2008--2009年开展了海涂耐盐水稻新种质创制研究.2008年进行海涂播种,育苗移栽耐盐适应性试验,米草/水稻杂交种34号,32号,杂交种子产量248 kg/667m2.2009年海涂筛选结合分子标记辅助双选择,海涂筛选32个组合中,耐盐稻谷产量207 kg/667m2以上有20个组合,平均稻谷产量326 kg/667m2,最低稻谷产量207.5 kg/667m2,最高稻谷产量596 kg/667m2.选育出了产量在400500 kg/667m2的耐盐水稻新组合6个,取得了突破性的进展.发现了耐盐甜秆水稻种质资源育种材料,秸秆可溶性糖含量在5.0%以上,比对照水稻提高65%以上.在60份杂交材料中选择18个杂交组合,经RAPD分析,有9个组合具有与大米草亲本共同条带且水稻亲本中有缺失的情形,表明9个组合远缘杂交种具有大米草亲本遗传成分
墨西哥玉米及其栽培管理措施

墨西哥玉米具有产量高,抗逆性强,分蘖多,生长快,再生性强,高产优质等特点,是我国北方和热带南方广泛种植的一种优良人工栽培牧草,但在我国亚热带地区引种和栽培较少,需要对其种植表现,适宜性,丰产性和饲用性进行引种栽培试验.本研究对墨西哥玉米的来源,品种特性,栽培管理,产量和饲用品质等进行总结,为对其进行进一步研究提供理论依据
IBA对金叶过路黄水插生根及株高增长量的影响

以野生金叶过路黄的老枝,嫩枝为插穗,探讨了0,10,50,100 mg/L IBA 4种浓度对金叶过路黄水插生根及株高增长量等指标的影响.结果表明:(1)老枝插穗的生根率,生根数量,株高增长量等生长指标均高于嫩枝,老枝插穗的水插效果优于嫩枝.(2)3种浓度IBA处理老枝的生根率,根数均极显著高于未处理老枝,而根长和侧根数差异不显著.(3)3种浓度IBA处理嫩枝的生根率,根数,根系发育指数和株高增长量均显著高于未处理嫩枝.(4)以50 mg/LIBA处理老枝的生根效果最好,生根率达100%,根系发育指数为1.73,显著高于其他处理
冷冻对猪体外成熟卵母细胞透明带消化时间和皮质颗粒分布的影响

采集猪卵巢表面直径25 mm卵泡中卵丘-卵母细胞复合体,经体外成熟后进行玻璃化冷冻,观察其解冻后透明带消化所需时间和皮质颗粒分布状况,探讨冷冻对体外成熟卵母细胞透明带消化时间和皮质颗粒分布的影响.结果表明:卵母细胞冷冻-解冻后,透明带消化时间显著缩短,皮质颗粒仍呈线状排列于细胞质膜下
禽源大肠杆菌多重耐药性与Ⅰ类整合子的关系

对1980--1990年的37株禽源致病性大肠杆菌进行14种抗菌药物敏感性测定和Ⅰ类整合子(IntI)PCR扩增,测序以及相同大小的IntI酶切分析等.结果表明,37株分离菌中有26株大肠杆菌是多重耐药菌株(耐受3种以上抗菌药物),多重耐药率为70.3%;有23株检测到了IntI,阳性检测率为62.3%.IntI大小为5003 300 bp;整合子中最常见的基因盒为dfr17(甲氧苄啶耐药基因),aad A5(链霉素,大观霉素耐药基因),最主要的基因盒排列为dfr17-aad A5.携带dfr17的绝大多数菌株对磺胺嘧啶耐药,携带aad A5的大多数菌株对链霉素不敏感,大小相同的I类整合子有相同的酶切图谱.大肠杆菌的多重耐药性与IntI的阳性检测率相关
适合中国南方栽培的蚕豆新品种及其高产栽培技术

蚕豆是我国人民喜爱食用的冷季食用豆新品种之一,也是长江流域主要的速冻出口豆类品种.本地区常年蚕豆栽培面积在26.67万hm2左右,其中40%左右用来鲜销,但适合本地区栽培的专用蚕豆新品种非常缺乏.为进一步给本地区广大豆农提供新品种及高产栽培技术,本文就适合中国南方栽培的高产,优质蚕豆新品种和高产栽培技术进行综合评述,供广大科研工作者和农业技术推广人士及广大豆农参考
氯虫·噻虫嗪对稻纵卷叶螟的毒力及田间试验

研究了氯虫.噻虫嗪(氯虫苯甲酰胺与噻虫嗪)混配对稻纵卷叶螟的室内毒力,田间防效,对稻飞虱的兼治作用和对天敌蜘蛛的影响,以及对水稻增产的效果.结果表明:氯虫.噻虫嗪对稻纵卷叶螟48 h致死中浓度为5.23 mg/L.氯虫.噻虫嗪等量混配药剂的共毒系数为227.38,具有很好的增效作用;40%氯虫.噻虫嗪水分散粒剂在使用量为48 g/hm2下对稻纵卷叶螟的防治效果为97.41%.同时对稻飞虱的兼治作用达66.96%;对天敌蜘蛛的影响小于对照药剂且对水稻具有明显增产效果
盐胁迫对棉种萌发及幼苗生长的影响

对2个耐,感盐碱棉花品种在不同盐分浓度土壤中的种子萌发特性和幼苗生长情况进行了研究.结果表明:盐分浓度越高,对棉花种子萌发的抑制作用越明显;在低盐土壤环境中,耐盐碱新品系苏研128种子萌发的耐盐胁迫能力强于盐碱敏感品种泗抗1号;当土壤盐分浓度≥0.40%时,耐,感盐碱品种均丧失发芽能力;2个品种在无盐土壤中棉苗生长势相同,在低盐胁迫条件下,耐盐碱新品系比感盐碱品种具有较强的干物质积累能力和发根能力;盐碱植棉过程中,盐分对棉苗根部的抑制作用强于地上部分,提高棉花在盐碱土壤中的发根能力是今后棉花耐盐碱育种的关键技术
旱作条件下播期对洛旱6号小麦生育规律的影响

对洛旱6号小麦的幼穗分化,籽粒灌浆和分蘖成穗三大生育规律进行了研究.结果表明,随着播期的推迟,洛旱6号幼穗分化的总时间缩短,二棱期经历的时间先增加后减少,10月4日播种和10月24日播种分别比10月14日播种缩短了4 d和18 d.洛旱6号的自我调节能力较强,平均灌浆速率在1.5531.806 g/(d.1 000粒)之间.在10月4日播种情况下平均灌浆速率和最大灌浆速率较大,灌浆时间3538 d,千粒重稳定在46 g以上.针对灌浆速率而言,以10月上旬播种对洛旱6号最为有利.洛旱6号主要依靠主茎和第1个和第2个一级分蘖成穗,随着播期的推迟,总分蘖数和成穗数逐渐减少.因此,洛旱6号适宜早播,最佳播种期为10月4--14日
2009年江苏省泰兴市小麦测产报告分析

为了解江苏省泰兴市不同小麦品种以及不同乡镇间种植小麦品种的产量情况,在小麦乳熟末期,随机测定了全市21个乡镇310个村9个小麦品种的单位面积穗数,每穗粒数,并估算了理论产量.结果表明,2009年全市小麦理论产量为6 663.6 kg/hm2,宁麦13和扬麦16产量较高,分别为6 994.5和6 987.5 kg/hm2,比全市平均理论产量分别高26.1%和24.4%,均达极显著水平.不同乡镇间产量变幅为5 435.18 404.7 kg/hm2,元竹镇和泰兴镇的理论产量最高,均超过8 250 kg/hm2.全市310个村小麦理论产量分布范围接近于正态分布,扬麦16,宁麦13和华麦2号3个品种在8个村的理论产量均超过9 000 kg/hm2
离体培养下小麦幼胚愈伤组织诱导率与分化率的研究

以5个小麦品种的幼胚为外植体,采用MS诱导培养基和分化培养基,研究不同基因型间愈伤组织诱导的差异,以及2,4-D浓度和不同的光照条件对愈伤组织的影响.随2,4-D浓度的增大,小麦幼胚分化率呈单峰曲线变化,且品种间差异很大,对多数品种而言,适宜的2,4-D浓度为15 mg/L
斜纹夜蛾核型多角体病毒ⅡORF56基因的序列分析及原核表达

对斜纹夜蛾核型多角体病毒ⅡORF56基因的序列特征及原核表达进行了初步研究.ORF56基因编码区全长675 bp,编码224个氨基酸,预测编码蛋白分子量25.9 ku.序列分析显示,ORF56具有典型的晚期启动子特征序列GTAAG,推导的氨基酸序列中含有13个磷酸化位点和3个N-糖基化位点.PCR扩增获得该基因,克隆到融合表达载体pET-32 a(+)中,在大肠杆菌BL21中诱导表达.用纯化的融合蛋白免疫家兔,制备了多克隆抗体,为深入研究Sp ltMNPVⅡORF56的结构与功能提供基础
科技创新团队建设的实践与思考

科技创新团队是培养人才和催生重大科研成果的一种有效模式,加强创新团队建设是迅速提高科研实力和推动学科发展的一条有效途径.本文以江苏省农业科学院植物保护研究所如何加强科技创新团队建设为实例,提出在专业所科技创新团队的建设中,首先要确立为全省农业生产发展服务的宗旨,在为政府,企业,农户解决植物病虫害服务中谋求发展.如何把创新思路转化为推动科技创新团队建设的具体行动,只有抓住人才,抓住交流,抓住培养及配套措施,以重点项目为纽带,结合单位传统优势学科和研究特色,结合各级政府重大需求进行,才能取得突破性进展
国内外麻疯树最新研究进展

麻疯树是一种生长在热带和亚热带地区的落叶灌木,近年来由于各国能源危机显现而越来越受到广大研究人员重视.笔者根据最近几年国内外学者对麻疯树研究的最新进展作综述,特别是有关麻疯树与近缘作物如变叶珊瑚花和佛肚树的种间杂交后代农艺性状变化作重点介绍,供相关研究人员参考
细菌生物膜及细菌群体感应系统的研究进展

细菌生物膜(BBF)是细菌耐药性形成的重要机制之一,也是许多慢性感染性疾病反复发作和难以控制的主要原因.在BBF形成过程中,细菌的群体感应(QS)系统起重要作用.本文就细菌生物膜的结构以及细菌的群体感应系统在细菌生物膜形成中的作用进行综述
笫四脑室巨大畸胎瘤1例报告

讨论 颅内畸胎瘤相对少见,约占所有颅内肿瘤的 0.5%,可发生于任何年龄,但年龄越小发病率越高.几乎一半的畸胎瘤发生在松果体区,其次是鞍上区.本例位于第四脑室的巨大畸胎瘤实属罕见.诊断通常需高分辨CT和 MRI完成.畸胎瘤呈多样性,常为多囊性表现.半数.成熟畸胎瘤存在钙化,也可发现成熟的骨骼和牙齿.本例术前 MRI不易与表皮样及皮样囊肿、低级别胶质瘤和髓母细胞瘤区别,只能依靠病理检查确诊.不成熟畸胎瘤生长迅速,发现时已很大,患者多数年龄较小并且有复发趋势,单独行外科治疗效果不理想.成熟畸胎瘤生长缓慢,脑积水可能是主要症状,手术切除后预后相对较好.四脑室畸胎瘤易梗阻脑脊液循环通道引起脑积水,本例病程较短,颅高压症状显著,术中与四脑室底部、小脑上动脉等重要脑组织粘连紧密的包膜未强行剥离,故解除占位效应,疏通脑脊液循环是本例手术治疗的关键.成熟和不成熟的畸胎瘤都可发生恶变,故患者出院后要定期复查
Preparation, Morphology Transformation and Magnetic Behavior of Co_3O_4 Nano-Leaves

A series of cubic phase Co_3O_4 nano-leaves were prepared via a combined approach of solution reaction and calcination. According to x-ray diffraction and electron microscopy, we find that the Co_3O_4 grain size increases with calcination temperature. This can induce many gaps in the products. M-T and M-H magnetization measurements reveal the typical antiferromagnetic behavior of nano-leaves. The effective moments of the samples prepared at 300, 400 and 500℃ are 5.6, 5.8 and 5.7μB per formula unit (FU), respectively, larger than the bulk value of 4.14 μB/FU
Preparation of a Pd-Cu-Si Bulk Metallic Glass with a Diameter up to 11 mm

Pd_(77.5)Cu_6sSi_(6.5)(at.%) bulk metallic glass with a diameter up to 11mm was successfully fabricated by water quenching method together with melt purification. By using x-ray diffraction and transmission electron microscopy techniques, the structure of the as-prepared sample is confirmed to be glassy. The resulted sample with 11mm diameter indicates that the melt purification by fluxing method can effectively enhance the glass forming ability of Pd-Cu-Si alloy, and increase its critical size of glassy sample
超声速混合层气动光学畸变与抖动----BOS测量技术及其应用

超声速混合层的气动光学畸变与抖动严重恶化其光学性能,但现有测量技术限制了相关研究的时空分辨率.通过系统集成与开发,提出了基于背景纹影(background orient schlieren,BOS)矢量场的高分辨率全场气动光学畸变与抖动测量方法,分析了BOS的系统结构,灵敏度与分辨率等基本问题.利用BOS研究了超声速混合层流向结构的气动光学畸变与抖动,定量化不稳定涡运动造成的气动光学效应,利用时间相关技术确定了气动光学抖动效应的时间尺度.超声速混合层展向结构的畸变场展示了光线穿越超声速混合层流场所出现的条带型畸变结构,这种结构是制约其光学性能的主要瓶颈之一.气动光学畸变与抖动效应的定量化为超声速混合层光学应用提供了重要的实验依据
一种求解带有时间调度的四维长方体装填问题的启发式算法

长方体的Packing问题被证明是NP-hard问题. 对于低维度Packing问题,国内外学者给出了模拟退火算法、遗传算法、分枝限界算法、拟人算法等求解算法. 文中针对带有时间调度的三维长方体的Packing问题,引入封装级别、空间距离和周边生成序数等评判标准,提出了一种基于贪心策略的启发式算法. 该算法对每个长方体每一占角位置进行评判,依据空间利用率选择给定格局下的最佳放置长方体及其放置方式,并进行填放. 算法的运算复杂度是一个与容器参数A,B,C,T以及长方体数目n有关的多项式O(A2B2C2T2n5). 利用该算法对非闸断模式和闸断模式测试样例进行实验,算法求解得到非闸断模式测试样例的平均空间利用率为98.81%,闸断模式测试样例的空间平均利用率为99.87%. 并且,对于一半以上样例,该算法能够求出最优解. 实验说明该算法对于求解带有时间调度的三维长方体Packing问题十分有效
基于机械/电气坐标系变换的无轴承永磁同步电机建模

无轴承永磁同步电机具有两套定子绕组,即转矩绕组与悬浮力绕组.通过分析这两套绕组之间的磁链交链情况,提出机械/电气坐标系变换方法,基于该方法推导出无轴承永磁同步电机转矩绕组与悬浮力绕组的磁链方程与电压方程.在分析无轴承永磁同步电机内各部分洛仑兹力作用的基础上,给出无轴承永磁同步电机电磁转矩方程.在分析无轴承永磁同步电机各部分径向力数学表达形式的基础上,得出无轴承永磁同步电机径向悬浮力方程的完整形式.最后给出了实验系统控制框图和部分结果.该数学模型为无轴承永磁同步电机的仿真研究,实验波形分析及结构设计提供了理论依据
利用NARX神经网络由IMF与太阳风预测暴时SYM-H指数

SYM-H是一个重要的空间天气指数,它与Dst指数相似,是磁暴强度的表征,但SYM-H具有更高的时间分辨率.本文发展了一种具有输出时延反馈的非线性自回归神经网络(NARX)预测模式,由太阳风和IMF参数预测暴时SYM-H指数的变化.与BP网络和Elman网络相比,预测效果显著改善.用15个强磁暴(含5个Minimal SYM-H<-200nT的超强磁暴)进行检验,预测与实测SYM-H指数的相关系数总体达到0.91;对于5个超强磁暴,相关系数最低为0.91,相应的磁暴为2001年3月最小SYM-H达-434nT的磁暴,对两个SYM-H小于-300nT的磁暴预测相关系数分别达0.93和0.96.在NARX网络中将适当长度(约120min)的SYM-H指数输出,反馈给网络外部输入,即输入中包含环电流内部准实时与历史状态信息,是使模式预测能力在已有基础上得以大大提高的关键;说明除了行星际的直接驱动之外,环电流自身状态对磁暴的发展变化,特别是对于恢复相过程有重要作用,在利用神经网络对环电流指数进行预测时必须恰当地加以考虑
中国科学家首次合成一个完整的核酸分子----酵母丙氨酸转移核糖核酸的人工全合成

<正>"酵母丙氨酸转移核糖核酸(酵母丙氨酸tRNA)人工全合成"研究结果先后发表在1982年的<<科学通报>>[1]和1983年的<<中国科学>>[2]上.本工作启动于1968年,完成于1981年11月,是继我国1965年在世界上首次人工合成蛋白质----结晶牛胰岛素后,又在世界上首次人工合成一个核酸分子,其组成,序列和
8.64-11.62 GHz CMOS VCO and divider in a zero-IF 802.11a/b/g WLAN and Bluetooth application

A fully integrated VCO and divider implemented in SMIC 0.13-μm RFCMOS 1P8M technology with a 1.2 V supply voltage is presented. The frequency of the VCO is tuning from 8.64 to 11.62 GHz while the quadrature LO signals for 802.11a WLAN in 5.8 GHz band or for 802.11b/g WLAN and Bluetooth in 2.4 GHz band can be obtained by a frequency division by 2 or 4, respectively. A 6 bit switched capacitor array is applied for precise tuning of all necessary frequency bands. The testing results show that the VCO has a phase noise of-113 dBc @ 1 MHz offset from the carrier of 5.5 GHz by dividing VCO output by two and the VCO core consumes 3.72 mW. The figure-of-merit for the tuning-range (FOMT) of the VCO is -192.6 dBc/Hz
Theoretical analysis of enhanced light output from a GaN light emitting diode with an embedded photonic crystal

The enhancement of the light output of an embedded photonic crystal light emitting diode is investigated based on the finite-difference time-domain modeling. The embedded photonic crystal (PC) lattice type, multi-layer embedded PC, distance between the multiple quantum well and the embedded PC are studied. It is found that the embedded one dimensional PC can act as well as embedded two dimensional PCs. The emitted light flux in the up direction can be increased by a new kind of multi-layer embedded PC. Also, we show that the light output in the up direction for the LED with both surfaces and embedded PC could be as high as five times that of a conventional LED
Biases in hydrostatic mass profiles introduced by hot gas substructures: Chandra study of four galaxy clusters

By analyzing the azimuthal variations of total gravitating mass profiles in the central 300 h_(71)~(-1) kpc regions of four galaxy clusters with Chandra data, we find that the azimuthally-averaged mass profiles may have been systematically underestimated by 16_(-8)~(+9)% at lσ significance in the 50-100 h_(71)~(-1) kpc regions, probably due to the prevailing existence of 2-D hot gas substructures in 100-300 h_(71)~(-1) kpc. The mass biases become negligible (-7_(_9)~(+11)%) at > 150 h_(71)~(-1) kpc. We confirm the results that the gas temperature maps can be used to probe the departure from hydrostatic equilibrium and help quantify the systematic biases in X-ray mass measurements in the central regions of clusters
Plant Immunity Triggered by Microbial Molecular Signatures

Pathogen/microbe-associated molecular patterns (PAMPs/MAMPs) are recognized by host cell surfacelocalized pattern-recognition receptors (PRRs) to activate plant immunity. PAMP-triggered immunity (PTI) constitutes the first layer of plant immunity that restricts pathogen proliferation. PTI signaling components often are targeted by various Pseudomonas syringae virulence effector proteins, resulting in diminished plant defenses and increased bacterial virulence. Some of the proteins targeted by pathogen effectors have evolved to sense the effector activity by associating with cytoplasmic immune receptors classically known as resistance proteins. This allows plants to activate a second layer of immunity termed effector-triggered immunity (ETI). Recent studies on PTI regulation and P. syringae effector targets have uncovered new components in PTI signaling. Although MAP kinase (MAPK) cascades have been considered crucial for PTI, emerging evidence indicates that a MAPK-independent pathway also plays an important role in PTI signaling
Effects of fractal gating of potassium channels on neuronal behaviours

The classical model of voltage-gated ion channels assumes that according to a Markov process ion channels switch among a small number of states without memory, but a bunch of experimental papers show that some ion channels exhibit significant memory effects, and this memory effects can take the form of kinetic rate constant that is fractal. Obviously the gating character of ion channels will affect generation and propagation of action potentials, furthermore, affect generation, coding and propagation of neural information. However, there is little previous research on this series of interesting issues. This paper investigates effects of fractal gating of potassium channel subunits switching from closed state to open state on neuronal behaviours. The obtained results show that fractal gating of potassium channel subunits switching from closed state to open state has important effects on neuronal behaviours, increases excitability, rest potential and spiking frequency of the neuronal membrane, and decreases threshold voltage and threshold injected current of the neuronal membrane. So fractal gating of potassium channel subunits switching from closed state to open state can improve the sensitivity of the neuronal membrane, and enlarge the encoded strength of neural information
Control of reaction channels of CsI molecule by ultra-short laser pulse

The influence of the ultra-short pulse wavelength on the populations in the three electronic states of CsI molecule is investigated using the time-dependent wave packet method. The calculated results show that the populations in the two excited states approach to the maxima at the wavelengths of 369 nm and 297 nm, respectively. The photodissociation reaction channels of the CsI molecule can be chosen by controlling the pump pulse wavelength
Quantum thermal discord in a two-spin-1/2 XXZ model

We study the quantum discord in a two-spin-1/2 XXZ model in thermal equilibrium at temperature T in the presence of an external magnetic field B. Special attention is paid to the dependence of quantum discord on the temperature T and magnetic field B. It is found that quantum thermal discord is more robust than concurrence against temperature, in the sense that quantum thermal discord does not vanish at finite temperatures, but concurrence vanishes completely at a critical temperature
Development and validation of a liquid chromatography-mass spectrometry metabonomic platform in human plasma of liver failure caused by hepatitis B virus

This paper presents an liquid chromatography (LC)/mass spectrometry (MS)-based metabonomic platform that combined the discovery of differential metabolites through principal component analysis (PCA) with the verification by selective multiple reaction monitoring (MRM). These methods were applied to analyze plasma samples from liver disease patients and healthy donors. LC-MS raw data (about 1000 compounds), from the plasma of liver failure patients (n +AD0- 26) and healthy controls (n +AD0- 16), were analyzed through the PCA method and a pattern recognition profile that had significant difference between liver failure patients and healthy controls (P +ADw- 0.05) was established. The profile was verified in 165 clinical subjects. The specificity and sensitivity of this model in predicting liver failure were 94.3 and 100.0+ACU-, respectively. The differential ions with m/z of 414.5, 432.0, 520.5, and 775.0 were verified to be consistent with the results from PCA by MRM mode in 40 clinical samples, and were proved not to be caused by the medicines taken by patients through rat model experiments. The compound with m/z of 520.5 was identified to be 1-Linoleoylglycerophosphocholine or 1-Linoleoylphosphatidylcholine through exact mass measurements performed using Ion Trap-Time-of-Flight MS and METLIN Metabolite Database search. In all, it was the first time to integrate metabonomic study and MRM relative quantification of differential peaks in a large number of clinical samples. Thereafter, a rat model was used to exclude drug effects on the abundance of differential ion peaks. 1-Linoleoylglycerophosphocholine or 1-Linoleoylphosphatidylcholine, a potential biomarker, was identified. The LC/MS-based metabonomic platform could be a powerful tool for the metabonomic screening of plasma biomarkers
Effects of C0_2 Enrichment on Photosynthesis, Growth, and Biochemical Composition of Seagrass Thalassia hemprichii (Ehrenb.) Aschers

The effects of CO_2 enrichment on various ecophysiological parameters of tropical seagrass Thalassia hemprichii (Ehrenb.) Aschers were tested. T. hemprichii, collected from a seagrass bed in Xincun Bay, Hainan island of Southern China, was cultured at 4 CO_2(aq) concentrations in flow-through seawater aquaria bubbled with CO_2. CO_2 enrichment considerably enhanced the relative maximum electron transport rate (RETRmax) and minimum saturating irradiance (E_k) of T. hemprichii. Leaf growth rate of CO_2enriched plants was significantly higher than that in unenriched treatment. Nonstructural carbohydrates (NSC) of T. hemprichii, especially in belowground tissues, increased strongly with elevated CO_2(aq), suggesting a translocation of photosynthate from aboveground to belowground tissues. Carbon content in belowground tissues showed a similar response with NSC, while in aboveground tissues, carbon content was not affected by CO_2 treatments. In contrast, with increasing C0_2(aq), nitrogen content in aboveground tissues markedly decreased, but nitrogen content in belowground was nearly constant. Carbon: nitrogen ratio in both tissues were obviously enhanced by increasing CO_2(aq). Thus, these results indicate that T. hemprichii may respond positively to CO_2-induced acidification of the coastal ocean. Moreover, the CO_2-stimulated improvement of photosynthesis and NSC content may partially offset negative effects of severe environmental disturbance such as underwater light reduction
Quantitative Analysis of Cytokinins in Plants by High Performance Liquid Chromatography: Electronspray Ionization Ion Trap Mass Spectrometry

The present paper introduces a highly sensitive and selective method for simultaneous quantification of 12 cytokinins (free form and their conjugates). The method includes a protocol of extraction with methanol/water/formic acid (15/411, v/v/v) to the micro-scale samples, pre-purification with solid phase extraction (SPE) cartridges of the extracts, separation with a high performance liquid chromatography (HPLC) and detection by an electrospray ionization ion trap mass spectrometry (ESI-lon trap-MS) system in a consecutive ion monitoring (CRM) mode at the three stage fragmentation of mass spectrometry (MS3). The lowest detection level of the cytokinins of the method reaches 0.1-2.0 pg with a very wide range of linear regression from 1-512 pg, at the coefficient factors of 0.98-0.99. The feasibility of this method has been proven in the application of the method to the analysis of the trace-amount contents of cytokinins in the micro-scale samples of various types of plant materials, such as aerial parts of rice and poplar leaves etc. 12 endogenous cytokinins had been identified and quantified in the plant tissues, with an acceptable relatively higher recovery rate from 40% to 70%
Promotion of markerless deletion of the actinorhodin biosynthetic gene cluster in Streptomyces coelicolor

The standard gene disruption and replacement to delete the actinorhodin biosynthetic gene cluster (Act) in Streptomyces coelicolor was inefficient, and the polymerase chain reaction-targeting of the cosmid could efficiently delete the Act, but still was a time-consuming procedure for markerless gene replacement. By using optimal Streptomyces codons, we synthesized a sce S gene encoding identical amino acid sequence as the chromosome rarecutting meganuclease I-sce I of the Saccharomyces cerevisiae mitochondria. Expression of sce S gene in S. coelicolor resulted in promotion of homologous recombination and subsequently, successful achieved markerless deletion of the Act. The sce S system may be useful for the sequential markerless deletions of chromosomal segments in Streptomyces