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21.
台湾医学图书馆联盟的发展与特色   总被引:1,自引:0,他引:1  
介绍了台湾地区5个知名的医学图书馆联盟,并进一步分析其基本特色。  相似文献   
22.
网络图书馆有效拓展了传统图书馆联盟的各项服务功能,为现代图书馆提供了更为广泛的信息服务条件,是数字时代图书馆联盟合作的新形式。大力加强网络图书馆建设,使资源共知、共建、共享的理念更好地融入图书馆业务之中,不断推进图书馆联盟的发展。  相似文献   
23.
Due to evolving molecular and informatics technologies, modern genome sequencing projects have more different characteristics than what most biologists have become accustomed to during the capillary-based sequencing era. In this paper, we explore the characteristics that made past insect genome projects successful and place them in the context of next-generation sequencing. By taking into account the intricacies of whitefly biology and the community, we present a roadmap for whitefly-omics, which focuses on the formation of an international consortium, deployment of informatic platforms and realistic generation of reference sequence data.  相似文献   
24.
A selected microbial consortium (SMC) capable of degrading two specific herbicides, alachlor (2-chloro-2′,6′-diethyl-N-[methoxymethyl]-acetanilide; AL) and atrazine (2-chloro-4-ethylamino-6-isopropylamino-S-triazine; AT) was isolated from a pesticide-contaminated mix-load site soil. Evaluation of bioaugmentation as a feasible bioremediation strategy for this mix-load site soil (Site 5A) was initiated in standard laboratory biometer flasks utilizing the isolated SMC. The biometer flasks were monitored for CO2 evolution and pesticide degradation. The total amount of CO2 evolved from the treated biometer flasks was significantly different from the control flasks. The rate of CO2 evolution was 2.6 times faster in the treated soil (0.0123 mM CO2 d−1 vs. 0.0048 mM CO2 d−1). The total net CO2 produced in the treated biometer flasks was 0.9481 mM, representing mineralization of approximately 10% of the AT and AL initially present. Forty-eight percent of AT and 70% of AL was degraded in the inoculated biometer flasks. The first-order rate constants were 0.0064 d−1 and 0.1331 d−1 for AT and AL, respectively. The calculated half-life of AT was 108 d while a 50% decrease in AL occurred by Day 5. In just 2 d, 20% of the AT was degraded while only 10% of the AL disappeared. The initial fast degradation rate of AT was followed by a much slower, more gradual degradation rate period that lasted about 35 d. Alternatively, the rate of AL degradation increased after the second day resulting in 60% of the AL being transformed by the end of the first week. Alachlor degradation appeared to be dependent upon AT degradation especially during the first several days of the incubation period. Complete disappearance of the herbicides over the study time was not achieved.  相似文献   
25.
Perennial fruits crops by the virtue of their nutritional qualities have already emerged as a major alternative, cutting short the menacing load on the consumption of traditional monotonous cereal/tuber crop-based diet. A nutrient management-based production system of perennial fruit crops is inherently complex to understand due to large variation in nutrient use efficiency (NUE). The current state of diagnosis of nutrient constraints in the current season-standing crop has minimum efficacy. Therefore, the development of production-linked nutrient norms using crop-specific index plant parts needs a thorough revisit at the orchard level using conventional basin irrigation versus fertigation. The application of hyperspectral analysis as proximal sensing of nutrient stress has started imparting precision to nutrient constraint diagnosis. On the other hand, the biggest constraint in making soil test ratings more purposeful is the non-redressal of spatial variation in soil fertility in the form of soil fertility analogs vis-a-vis fruit crops. The conjoint use of geoinformatics and Nutrient Experts as decision support tool(s) accommodating site-specific nutrient management strategy, newer concept of fertigation such as open-field hydroponics and variable-rate application as possible improvements in NUE collectively using a logical relationship between canopy volume and nutrient requirement, and exploiting further the nutrient–harmone and nutrient–microbe (in the consortium mode) synergies have yielded a definite edge over conventional methods of nutrient management options in fruit crops.  相似文献   
26.
玉米秸秆低温降解菌的分离与鉴定及复配菌降解效果研究   总被引:2,自引:0,他引:2  
在15℃下利用纤维素刚果红培养基,采用平板涂布法分离具有明显水解圈的单菌株11株,并根据单菌特性进行有效组配,在液态、固态和模拟环境培养模式下,通过测定滤纸酶活性及玉米秸秆降解率进行复配菌筛选及降解效果评价。组配获得10组复配菌,复配菌A、D、G在15℃条件下培养可分解滤纸,且复配菌的降解能力优于单菌。复配菌在3种培养模式条件下的玉米秸秆降解率总体趋势为模拟环境培养>固体培养≥液体培养,其中复配菌G在模拟环境培养条件下降解效果最优,滤纸酶活性(FPA)为32.96 U/mL,较CK增加20.98 U/mL;秸秆降解率为47.56%,较CK增加21.56%。经16SrDNA分子鉴定,复配菌G由Pseudomonas sp.CellulosimicrobiumcellulansAchromobactermarplatensisPseudomonas fuscovaginae组成。  相似文献   
27.
针对基于属性的联盟链应用访问控制模型可能存在拜占庭节点而导致属性信息、访问控制策略查询结果不可信的问题,结合猕猴桃溯源场景的实际需求,提出了一种基于PBFT的联盟链应用访问控制方案。该方案使用属性权威作为联盟链实体组织的属性证书颁发机构以及PBFT的查询验证节点,对访问请求内容生成签名并验证;属性证书中存储主体与权限相关的属性信息;基于PBFT对用户属性、数据属性、访问控制策略查询验证,确保访问控制过程的可信性。基于Hyperledger Fabric原型系统测试表明,当记账节点中的拜占庭节点少于节点总数1/3时系统能够正常运行;当交易发送率在100~1 500 TPS之间变化时,交易吞吐量在交易发送率达到300 TPS后趋于稳定,平均时延在交易发送率达到400 TPS后趋于稳定,满足联盟链猕猴桃溯源的应用需求。  相似文献   
28.
利用鸡粪和锯末为原料进行自然通风堆肥试验,引入复合菌剂,研究外源微生物对堆肥的影响。实验共设6个处理,从接种量出发,设堆肥初始加入菌剂量0.1%、0.2%、0.5%及空白;从接种时间考虑,设初始不接种、第14d加入0.2%,以及初始接种0.1%、第14d又接入0.1%的菌剂。结果表明,初始接种对温度升高有促进作用,在后期起保温作用,温度多次出现回升,有利于物料的充分分解,并且该菌剂有利于有机碳的分解和氮的保存,而后期接种加速了温度下降,影响效果小。综合各个处理,初始接种0.2%的处理效果最佳。  相似文献   
29.
Contaminated soil from a 100-year-old mix-load site located in Reading, PA was evaluated for its potential to provide indigenous microorganisms capable of degrading two widely utilized herbicides, atrazine (2-chloro-4-ethylamino-6-isopropylamino-S-triazine; AT) and alachlor (2-chloro-2′,6′-diethyl-N-[methoxymethyl]-acetanilide; AL). Three different locations from the site were chosen for experimentation based on herbicide handling activities. Standard enrichment techniques were used to isolate a selective microbial consortium (SCM) with the desirable degrading capabilities. Three enrichment treatment schemes were evaluated; AT and AL, AL alone, and only AT. Degradative organisms were isolated from only one of the sample locations. Considerable differences in the soil parameters of the three sample locations were found that might have had an effect on the ability of the indigenous microbial populations within the soil to degrade AT and AL. In the initial cultures from this location, degradation occurred in the AT and AL treatment only. Because the AT and AL were the only sources of carbon and nitrogen (N) for the microbes, these results suggest that AL alone was not a sufficient N source. In general, the ability to degrade AL by the SMC was dependent on AT degradation. Alachlor degradation did not begin until approximately 15% of the AT was transformed. Once all of the AT was removed very little further AL degradation occurred. The average half-life (t1/2) of AT was 7.5 d, while average t1/2 for AL degradation was 11 d. Individual colonies from the SMC were identified by fatty acids methyl ester (FAME) analysis. Five strains were identified with similarity indexes above 70%. These isolates included the following: Alcaligenes xylosoxydans subsp. denitrificans, Alcaligenes xylosoxydans subsp. xylosoxydans, Pseudomonas putida, Pseudomonas marginalis, and Providencia rustigianii.  相似文献   
30.
通过对电子文献联盟采购主题研究的概述,简析了联盟采购中的组织模式、采购模式、资源共享模式、集团内的利益问题,以及在采购中与生产者的合作和需兼顾的长远方针。目的在于给参加电子文献联盟采购成员和从事该主题研究者一些相关参考。  相似文献   
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