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81.
OLAP (On-Line Analytical Processing) is an approach to efficiently evaluate multidimensional data for business intelligence applications. OLAP contributes to business decision-making by identifying, extracting, and analyzing multidimensional data. The fundamental structure of OLAP is a data cube that enables users to interactively explore the distinct data dimensions. Processing depends on the complexity of queries, dimensionality, and growing size of the data cube. As data volumes keep on increasing and the demands by business users also increase, higher processing speed than ever is needed, as faster processing means faster decisions and more profit to industry. In this paper, we are proposing an Adaptive Hybrid OLAP Architecture that takes advantage of heterogeneous systems with GPUs and CPUs and leverages their different memory subsystems characteristics to minimize response time. Thus, our approach (a) exploits both types of hardware rather than using the CPU only as a frontend for GPU; (b) uses two different data formats (multidimensional cube and relational cube) to match the GPU and CPU memory access patterns and diverts queries adaptively to the best resource for solving the problem at hand; (c) exploits data locality of multidimensional OLAP on NUMA multicore systems through intelligent thread placement; and (d) guides its adaptation and choices by an architectural model that captures the memory access patterns and the underlying data characteristics. Results show an increase in performance by roughly four folds over the best known related approach. There is also the important economical factor. The proposed hybrid system costs only 10 % more than same system without GPU. With this small extra cost, the added GPU increases query processing by almost 2 times.  相似文献   
82.
Targeting papain family cysteine proteases is one of the novel strategies in the development of chemotherapy for a number of diseases. Novel cysteine protease inhibitors derived from 1-pyridylimidazo[1,5-a]pyridine representing pharmacologically important class of compounds are being reported here for the first time. The derivatives were initially designed and screened in silico by molecular docking studies against papain to explore the possible mode of action. The molecular interaction between the compounds and cysteine protease (papain) was found to be very similar to the interactions observed with the respective epoxide inhibitor (E-64c) of papain. Subsequently, compounds were synthesized to validate their efficacy in wet lab experiments. When characterized kinetically, these compounds show their Ki and IC50 values in the range of 13.75 to 99.30 µM and 13.40 to 96.50 µM, respectively. The thermodynamics studies suggest their binding with papain hydrophobically and entropically driven. These inhibitors also inhibit the growth of clinically important different types of Gram positive and Gram negative bacteria having MIC50 values in the range of 0.6–1.4 µg/ml. Based on Lipinski’s rule of Five, we also propose these compounds as potent antibacterial prodrugs. The most active antibacterial compound was found to be 1-(2-pyridyl)-3-(2-hydroxyphenyl)imidazo[1,5-a]pyridine (3a).  相似文献   
83.

Background

Muscle satellite cells (MSCs) represent a devoted stem cell population that is responsible for postnatal muscle growth and skeletal muscle regeneration. An important characteristic of MSCs is that they encompass multi potential mesenchymal stem cell activity and are able to differentiate into myocytes and adipocytes. To achieve a global view of the genes differentially expressed in MSCs, myotube formed-cells (MFCs) and adipocyte-like cells (ALCs), we performed large-scale EST sequencing of normalized cDNA libraries developed from bovine MSCs.

Results

A total of 24,192 clones were assembled into 3,333 clusters, 5,517 singletons and 3,842contigs. Functional annotation of these unigenes revealed that a large portion of the differentially expressed genes are involved in cellular and signaling processes. Database for Annotation, Visualization and Integrated Discovery (DAVID) functional analysis of three subsets of highly expressed gene lists (MSC233, MFC258, and ALC248) highlighted some common and unique biological processes among MSC, MFC and ALC. Additionally, genes that may be specific to MSC, MFC and ALC are reported here, and the role of dimethylarginine dimethylaminohydrolase2 (DDAH2) during myogenesis and hemoglobin subunit alpha2 (HBA2) during transdifferentiation in C2C12 were assayed as a case study. DDAH2 was up-regulated during myognesis and knockdown of DDAH2 by siRNA significantly decreased myogenin (MYOG) expression corresponding with the slight change in cell morphology. In contrast, HBA2 was up-regulated during ALC formation and resulted in decreased intracellular lipid accumulation and CD36 mRNA expression upon knockdown assay.

Conclusion

In this study, a large number of EST sequences were generated from the MSC, MFC and ALC. Overall, the collection of ESTs generated in this study provides a starting point for the identification of novel genes involved in MFC and ALC formation, which in turn offers a fundamental resource to enable better understanding of the mechanism of muscle differentiation and transdifferentiation.  相似文献   
84.
Napiergrass (Pennisetum purpureum Schum.) is a high-yielding perennial biomass crop that is well adapted to the Southeast USA where poultry litter is readily available. This research was conducted to compare biomass production and nutrient utilization of napiergrass fertilized with either poultry litter or inorganic fertilizer. Each spring, approximately 100 kg ha?1 of N, 40 kg ha?1 P, and 90 kg ha?1 K were applied as poultry litter or equivalent inorganic fertilizer. Biomass was harvested each winter after senescence. For the first 2 years, dry matter yield did not differ among treatments, but in the third and fourth years, yields declined in all treatments and were lowest in the unfertilized treatment. Biomass N concentration and N removal were greatest in the inorganic treatment. In general, N removal exceeded the amount applied, suggesting that higher application rates may be necessary to maintain yields. Biomass P concentration and total P uptake were greatest in the litter fertilized treatment, demonstrating that napiergrass can remove some of the excess P from applied litter. Soil cores were taken periodically to assess changes in soil properties. After 2 years of production, soil pH in the surface layer (0–15 cm) was lower in the inorganic treatment than in the other treatments. After 4 years, total soil C had increased by an average of 3,180 kg ha?1 though fertilizer treatments did not differ. Yield declined in all treatments after 4 years and N supplementation is recommended for production in upland fields.  相似文献   
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87.
Latif  Sajid  Gurusinghe  Saliya  Weston  Paul A.  Quinn  Jane C.  Piltz  John W  Weston  Leslie A 《Plant and Soil》2020,447(1-2):199-218
Plant and Soil - Weed suppressive potential of annual pasture legumes has been previously described, the mechanism of interference with weeds has not been clearly elucidated. We, therefore, aimed...  相似文献   
88.
Abdul Malik  S. A.  Bazire  A.  Gamboa-Muñoz  A.  Bedoux  G.  Robledo  D.  García-Maldonado  J. Q.  Bourgougnon  N. 《Microbiology》2020,89(6):778-788
Microbiology - Macroalgae host a dense bacterial epibiome forming surface biofilms, which act as a biological defense by protecting the surface from macrofoulers. During experimental cultivation of...  相似文献   
89.
Abstract

Autoimmune responses against post-translationally modified antigens are a hallmark of several autoimmune diseases. In this work, we have studied the changes in alpha-2-macroglobulin (α2M) upon modification by peroxynitrite. Furthermore, we have evaluated the immunogenicity of modified α2M in experimental rabbits and rheumatoid arthritis (RA) patients. Peroxynitrite-modified α2M showed disturbed microenvironment and altered aromatic residues under UV and fluorescence studies. Aggregation, reduction in β-sheet content, production of nitrotyrosine and shift in amide I and II bands were observed in the modified α2M by polyacrylamide gel electrophoresis besides CD and FTIR spectroscopic analysis. The exposure of hydrophobic clusters and changes in contact positions were observed in ANS and ThT binding assays. Immunological studies using ELISA showed peroxynitrite-modified α2M as highly immunogenic producing high titre of specific antibodies in immunized rabbits. Cross-reactivity studies revealed the polyspecificity of the elicited antibodies. Direct binding ELISA and competitive inhibition studies confirmed the presence of circulating antibodies in the sera of RA patients having high specificity towards the peroxynitrite-modified α2M as compared to the native α2M. Sera from healthy (normal) human subjects showed lower binding with the native and modified protein. This study confirms that peroxynitrite induces structural modifications in α2M and makes it immunogenic. The presence of neo-antigenic determinants on modified α2M with enhanced binding for circulating autoantibodies in RA patients could offer new possibilities for diagnosis and etiopathology of the disease.

Communicated by Ramaswamy H. Sarma  相似文献   
90.
Haider  Saida  Sajid  Irfan  Batool  Zehra  Madiha  Syeda  Sadir  Sadia  Kamil  Noor  Liaquat  Laraib  Ahmad  Saara  Tabassum  Saiqa  Khaliq  Saima 《Neurochemical research》2020,45(11):2762-2774

Noise has always been an important environmental factor that induces health problems in the general population. Due to ever increasing noise pollution, humans are facing multiple auditory and non-auditory problems including neuropsychiatric disorders. In modern day life it is impossible to avoid noise due to the rapid industrialization of society. Continuous exposure to noise stress creates a disturbance in brain function which may lead to memory disorder. Therefore, it is necessary to find preventive measures to reduce the deleterious effects of noise exposure. Supplementation of taurine, a semi essential amino acid, is reported to alleviate psychiatric disorders. In this study noise-exposed (100 db; 3 h daily for 15 days) rats were supplemented with taurine at a dose of 100 mg/kg for 15 days. Spatial and recognition memory was assessed using the Morris water maze and novel object recognition task, respectively. Results of this study showed a reversal of noise-induced memory impairment in rats. The derangements of catecholaminergic and serotonergic levels in the hippocampus and altered brain antioxidant enzyme activity due to noise exposure were also restored by taurine administration. This study highlights the importance of taurine supplementation to mitigate noise-induced impaired memory via normalizing the neurochemical functions and reducing oxidative stress in rat brain.

  相似文献   
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