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81.
Cluster Computing - Cloud computing model offers various platforms services and provides a scalable, on-demand service at any time-anywhere manner. However, in the outsourcing strategy, users no...  相似文献   
82.
Russian Journal of Bioorganic Chemistry - In search of better antibacterial agents, a series of novel 5-((aryl)methyl)-3-(1H-indol-2-yl)isoxazole (IIIa–e) and...  相似文献   
83.
Crop growth largely depends on radiation. Radiation is the main impetus for photosynthesis and movement of photosynthates from source to sink. Therefore, identification of the optimum sowing windows and suitable cultivars for efficient utilization of radiation is of prime importance. A field study was conducted in red clay soil during 2014 and 2015 Kharif season and the treatments consisted of three genotypes and three sowing windows by using randomized complete block design with three replications. The effect of genotypes and sowing windows was found significant with respect to number of trifoliate leaves, leaf area ratio, dry matter production, grain numbers, pod length, test weight, grain yield, and stover yield of guar during 2014 as compared to 2015 sown crop. Statistically significant plant height, number of trifoliate leaves, number of branches, leaf area ratio, absolute growth rate, leaf area index, dry matter, grain number, pod length, grain yield, stover yield and a higher cumulative radiation interception were recorded with 15th August sown crop as compared to other sowing windows. The plant height, number of trifoliate leaves, number of branches, leaf area ratio, absolute growth rate, leaf area index, dry matter, grain number, pod length, grain yield, stover yield and maximum cumulative interception of radiation were significant with RGC-1003 as compared to RGC-936 and HG-365. It is observed that the incident PAR to dry matter accumulation conversion efficiency was varied with cultivars and different sowing windows which ranges from 0.74 g MJ−1 to 0.79 g MJ−1.  相似文献   
84.
Cholesterol is a fundamental molecule necessary for the maintenance of cell structure and is vital to various normal biological functions. It is a key factor in lifestyle-related diseases including obesity, diabetes, cardiovascular disease, and cancer. Owing to its altered serum chemistry status under pathological states, it is now being investigated to unravel the mechanism by which it triggers various health complications. Numerous clinical studies in cancer patients indicate an alteration in blood cholesterol level (either decreased or increased) in comparison to normal healthy individuals. This article elaborates on our understanding as to how cholesterol is being hijacked in the malignancy for the development, survival, stemness, progression, and metastasis of cancerous cells. Also, it provides a glimpse of how cholesterol derived entities, alters the signaling pathway towards their advantage. Moreover, deregulation of the cholesterol metabolism pathway has been often reported to hamper various treatment strategies in different cancer. In this context, attempts have been made to bring forth its relevance in being targeted, in pre-clinical and clinical studies for various treatment modalities. Thus, understanding the role of cholesterol and deciphering associated molecular mechanisms in cancer progression and therapy are of relevance towards improvement in the management of various cancers.  相似文献   
85.
Background: Breast cancer, a type of malignant tumor, affects women more than men. About one third of women with breast cancer die of this disease. Hence, it is imperative to find a tool for the proper identification and early treatment of breast cancer. Unlike the conventional data mining algorithms, fuzzy logic based approaches help in the mining of association rules from quantitative transactions.Methods: In this study a novel fuzzy methodology IFFP (Improved Fuzzy Frequent Pattern Mining), based on a fuzzy association rule mining for biological knowledge extraction, is introduced to analyze the dataset in order to find the core factors that cause breast cancer. This method consists of two phases. During the first phase, fuzzy frequent itemsets are mined using the proposed algorithm IFFP. Fuzzy association rules are formed during the second phase, indicating whether a person belongs to benign or malignant. This algorithm is applied on WBCD (Wisconsin Breast Cancer Database) to detect the presence of breast cancer.Results: It is determined that the factor, Mitoses has low range of values on both malignant and benign and hence it does not contribute to the detection of breast cancer. On the other hand, the high range of Bare Nuclei shows more chances for the presence of breast cancer.Conclusion: Experimental evaluations on real datasets show that our proposed method outperforms recently proposed state-of-the-art algorithms in terms of runtime and memory usage.  相似文献   
86.
Abstract

The decolorization of toxic azo dye Ponceau 4R by three strains of bacteria Bacillus sp. strain AK1, Lysinibacillus sp. strain AK2 and Kerstersia sp. strain VKY1 individually and in consortia was studied. At optimal conditions, up to 95%, 93% and 87% of the dye was decolorized by the strains AK1, AK2 and VKY1, respectively, in 24?h at 200?mg/L of the dye. Decolorization of the dye was optimized for different parameters such as the concentration of dye, pH, temperature and NaCl concentration. These strains were able to decolorize Ponceau 4R up to an initial concentration of 800?mg/L in the pH range of 5–10, temperature 25–55?°C and NaCl concentration up to 30?g/L. The dye decolorization efficiency of these strains was further enhanced by using different consortia of AK1, AK2 and VKY1 in various combinations. The complete decolorization of the dye by a consortium was achieved within 18?h at 200?mg/L. The cell-free extract of these strains grown on this dye exhibited a remarkable activity of azoreductase which is involved in the breakage of the azo bond. The steady-state kinetics of azoreductase, validated the ping pong Bi-Bi mechanism of enzyme action. UV–Vis spectra, HPLC, FTIR and LC-MS analysis of the dye decolorized samples showed the formation of 4-aminonaphthalene-1-sulphonic acid and 5-amino-6-hydroxynaphthalene-2, 4-disulphonic acid as the products of azo bond breakage. The phytotoxicity test of decolorized sample revealed a considerable reduction in the toxicity in comparison with the parent dye.  相似文献   
87.
Of late non-coding RNAs (ncRNAs)-mediated gene silencing is an influential tool deliberately deployed to negatively regulate the expression of targeted genes. In addition to the widely employed small interfering RNA (siRNA)-mediated gene silencing approach, other variants like artificial miRNA (amiRNA), miRNA mimics, and artificial transacting siRNAs (tasiRNAs) are being explored and successfully deployed in developing non-coding RNA-based genetically modified plants. The ncRNA-based gene manipulations are typified with mobile nature of silencing signals, interference from viral genome-derived suppressor proteins, and an obligation for meticulous computational analysis to prevaricate any inadvertent effects. In a broad sense, risk assessment inquiries for genetically modified plants based on the expression of ncRNAs are competently addressed by the environmental risk assessment (ERA) models, currently in vogue, designed for the first generation transgenic plants which are based on the expression of heterologous proteins. Nevertheless, transgenic plants functioning on the foundation of ncRNAs warrant due attention with respect to their unique attributes like off-target or non-target gene silencing effects, small RNAs (sRNAs) persistence, food and feed safety assessments, problems in detection and tracking of sRNAs in food, impact of ncRNAs in plant protection measures, effect of mutations etc. The role of recent developments in sequencing techniques like next generation sequencing (NGS) and the ERA paradigm of the different countries in vogue are also discussed in the context of ncRNA-based gene manipulations.  相似文献   
88.
A new series of complexes is synthesized by template condensation of oxalyldihydrazide and glyoxal in methanolic medium in the presence of trivalent chromium, manganese and iron salts forming complexes of the type: [M(C8H8N8O4)X]X2 where M = Cr(III), Mn(III), Fe(III) and X = Cl? 1, , CH3COO? 1. The complexes have been characterized with the help of elemental analyses, conductance measurements, magnetic susceptibility measurements, electronic, NMR, infrared and far infrared spectral studies. On the basis of these studies, a five coordinate square pyramidal geometry for these complexes has been proposed. The biological activities of the metal complexes were tested in vitro against a number of pathogenic bacteria and some of the complexes exhibited remarkable antibacterial activities.  相似文献   
89.
Abstract

Purine analogues and derivatives exhibit a broad range of pharmacological activities and are used in the chemotherapy of cancer, parasitic and viral infections, and for the suppression of immune responses. Undoubtedly, this wide range of biological activities reflect an equally wide number of biochemical sites of action, one of which is the purine de novo pathway. New agents which can either serve as inhibitors of enzymes involved in this pathway or as substrates are continually sought. The unique series of nucleosides described herein should meet these desired needs.

The synthesis of 1involved glycosylation of a suitably 4,5-disubstituted imidazole and subsequent cyclization of the imidazole nucleoside so formed to the imidazo[4,5-d]pyridazine nucleoside. Such methodology was successfully employed1,2 in the preparation of certain 4,7-disubstituted imidazo[4,5-d]pyridazine nucleosides. Chlorination of 1furnished 4-chloro-1-(2,3,5-tri-O-acetyl-β-D-ribo-furanosyl)imidazo[4,5-dlpyridazine (2) in 80% yield. This versatile intermediate can now serve as a precursor to a variety of 4-substituted imidazo[4,5-d]pyridazine nucleosides.  相似文献   
90.
Eukaryotic ribosome assembly requires over 200 assembly factors that facilitate rRNA folding, ribosomal protein binding, and pre-rRNA processing. One such factor is Rlp7, an essential RNA binding protein required for consecutive pre-rRNA processing steps for assembly of yeast 60S ribosomal subunits: exonucleolytic processing of 27SA3 pre-rRNA to generate the 5′ end of 5.8S rRNA and endonucleolytic cleavage of the 27SB pre-rRNA to initiate removal of internal transcribed spacer 2 (ITS2). To better understand the functions of Rlp7 in 27S pre-rRNA processing steps, we identified where it crosslinks to pre-rRNA. We found that Rlp7 binds at the junction of ITS2 and the ITS2-proximal stem, between the 3′ end of 5.8S rRNA and the 5′ end of 25S rRNA. Consistent with Rlp7 binding to this neighborhood during assembly, two-hybrid and affinity copurification assays showed that Rlp7 interacts with other assembly factors that bind to or near ITS2 and the proximal stem. We used in vivo RNA structure probing to demonstrate that the proximal stem forms prior to Rlp7 binding and that Rlp7 binding induces RNA conformational changes in ITS2 that may chaperone rRNA folding and regulate 27S pre-rRNA processing. Our findings contradict the hypothesis that Rlp7 functions as a placeholder for ribosomal protein L7, from which Rlp7 is thought to have evolved in yeast. The binding site of Rlp7 is within eukaryotic-specific RNA elements, which are not found in bacteria. Thus, we propose that Rlp7 coevolved with these RNA elements to facilitate eukaryotic-specific functions in ribosome assembly and pre-rRNA processing.  相似文献   
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