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1.
指出了低温是影响冬季寒冷地区生活污水处理效果的一个主要原因,在低温环境下,活性污泥中大多数中温菌的生长活性受到抑制,只有少数的耐冷菌可以存活下来并保持一定的活性。简要介绍了低温微生物的概念及分类,从细胞膜结构、低温酶、蛋白质合成以及冷休克蛋白等方面对耐冷菌的适冷机制进行分析,最后对耐冷菌在污水处理中的应用现状与发展方向进行了展望。  相似文献   
2.
Journal of Crop Science and Biotechnology - Due to the negative consequences of synthetic herbicides use and their reducing effectiveness due to development of resistant weeds, promotion of...  相似文献   
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A new cytotoxic thiodepsipeptide, verrucosamide (1), was isolated along with the known, related cyclic peptide thiocoraline, from the extract of a marine-derived actinomycete, a Verrucosispora sp., our strain CNX-026. The new peptide, which is composed of two rare seven-membered 1,4-thiazepane rings, was elucidated by a combination of spectral methods and the absolute configuration was determined by a single X-ray diffraction study. Verrucosamide (1) showed moderate cytotoxicity and selectivity in the NCI 60 cell line bioassay. The most susceptible cell lines were MDA-MB-468 breast carcinoma with an LD50 of 1.26 µM, and COLO 205 colon adenocarcinoma with an LD50 of 1.4 µM. Also isolated along with verrucosamide were three small 3-hydroxy(alkoxy)-quinaldic acid derivatives that appear to be products of the same biosynthetic pathway.  相似文献   
5.
This study assesses the impacts of local business incentives in the largest urban areas of Illinois, Michigan, and Wisconsin, three Midwestern states that share similar histories and settings. We assembled a unique dataset combining information on two types of incentives, tax increment financing districts and tax abatements, together with socio‐economic, geographic, fiscal, and spatial competitive characteristics for all of the municipalities in six metropolitan areas. The outcome measures include employment growth, establishment formation, and business relocation. The analysis extends knowledge of the effects of economic development incentives in two ways. First, we improve upon previous research by incorporating key factors in municipal decisions to offer incentives. Second, we add to limited empirical evidence concerning local incentives following the Great Recession. Variation in the use of incentives reflects not only local decision‐making but also differing fiscal capacities and situations of adaptation to adverse economic conditions, with some governments pulling back on incentives and others initiating new approaches to retain or lure businesses.  相似文献   
6.
梁毅  李晓杰 《蔬菜》2020,(12):81-82
“秀球赤玉”是以高花青素深紫皮不育系562A为母本,以高花青素深紫皮自交系2014-7-10-6为父本培育的中日照、早熟、高花青素三系杂交种。其表现:鳞茎大圆球形,花青素含量高达68.8 mg/g;洋葱鳞片从外至里均为深紫色,色泽亮,外观漂亮,商品率高;辣味轻,口感脆甜,可生食;植株长势强,抗病,耐抽薹,分球、裂球少;假茎细且收口紧,耐贮性好;平均单球质量600~1 000 g,667 m2产量8 000~12 000 kg;适宜在中日照地区推广,2019—2020年累计推广面积超过1 500 hm2。  相似文献   
7.
Direct seeding is increasingly being practiced in rice cultivation areas because it saves labour and reduces cost of production and management. In this study, four japonica‐type breeding lines were developed from a cross of a japonica cultivar and an AG‐tolerant donor, KHO, using marker‐assisted selection. Validation of the target genes AG1 and AG2 in the selected lines was examined by PCR analysis and the background recovery rate by the recurrent parent was confirmed by genotyping using a 6K SNP chip. Compared to the recurrent, the survival rates of the selected lines were improved in a range from 33% to 115% in three conditions; in particular, the survival rate was increased in more than twice that of the recurrent parent under the hypoxic condition. The main agronomic trait, yield and quality‐related traits were similar to those of the recurrent parent. The use of these lines will contribute to the expansion of the cultivation area due to the proven economic benefits of direct seeding in Korea.  相似文献   
8.
As suggested by the Office International des Epizooties (OIE), fishes belonging to the genus Oplegnathus are more sensitive to megalocytivirus infection than other fish species including red sea bream (Pagrus major). To assess the roles of the innate immune response to these different susceptibilities, we cloned the genes encoding inflammatory factors including IL‐8 and COX‐2, and the antiviral factor like Mx from red sea bream for the first time and performed phylogenetic and structural analysis. Analysed expression levels of IL‐1β, IL‐8 and COX‐2 and the antiviral factor like Mx genes performed with in vivo challenge experiment showed no difference in inflammatory gene expression or respiratory burst activity between red sea bream and rock bream (Oplegnathus fasciatus). However, the Mx gene expression levels in red sea bream were markedly higher than those in rock bream, suggesting the importance of type I interferon (IFN)‐induced proteins, particularly Mx, during megalocytivirus infection, rather than inflammation‐related genes. The in vitro challenge experiments using embryonic primary cultures derived from both fish species showed no difference in cytopathic effects (CPE), viral replication profiles, and inflammatory and Mx gene expression pattern between the two fish species.  相似文献   
9.
Graphene is classified as a carbon-based material. Structurally, graphene is made up of carbon-based two-dimensional atomic crystals and a one atom thick planar sheet of sp2-bonded carbon atoms. This sort of arrangement in graphene makes it a unique material with exceptional mechanical, physicochemical, thermal, electrical, optical, and biomedical properties. Methods for graphene-based fabric production mainly use graphene-based materials such as graphene (G), graphene oxide (GO), and reduced graphene oxide (rGO) coated on fabric or yarn. Waterborne polyurethane (WPU) is one of the most rapidly developing and active branches of polyurethane chemistry. More and more attention is being paid to graphene-coated fabrics owing to their low temperature flexibility, the presence of zero or very few VOCs (volatile organic compounds), water resistance, pH stability, superior solvent resistance, excellent weathering resistance, and desirable chemical and mechanical properties. It is used as a coating agent or adhesive for fibers, textiles, and leather. Also, graphene-containing materials have been used to enhance the properties of WPU. In this study, graphene/WPU composite solution and film was prepared to conduct basic research for developing electrical heating textiles which is not harmful to the human body, flexible and excellent in electrical properties. Graphene/WPU composite solutions were prepared with a graphene content of 0, 2, 4, 8, and 16 wt%, and graphene/WPU film was prepared with solution casting method. The graphene contents were analyzed for their surface morphology, electrical properties, and electrical heating properties.  相似文献   
10.
茶氨酸合成酶基因的SNP挖掘和遗传定位   总被引:1,自引:0,他引:1  
茶氨酸合成酶(Theanine synthetase,TS)基因是茶树茶氨酸代谢过程中的关键酶基因。本研究以氨基酸含量差异明显的亲本及其杂交所得F_1子代为研究材料,克隆TS基因的c DNA序列,挖掘其SNPs位点,并成功将杂合SNP位点定位在遗传连锁群上。研究结果显示,通过序列比对在亲本间检测到3个SNPs,验证得到1个杂合的位点SNP735。将此位点成功转化为dCAPS标记,该标记在子代中的基因型分离比为1∶1,利用该群体已构建的茶树遗传图谱进行遗传定位,将dCAPS标记定位在连锁群LG03上,相邻标记为TM299和TM517。联合此标记及其相邻标记与游离氨基酸总含量和茶氨酸含量进行统计分析,表明具有显著的相关性。  相似文献   
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