1,201 research outputs found
Web workload analysis and session characterization using clustering
Web servers have a significant presence in today\u27s Internet. Corporations want to achieve high availability, scalability, and consistent performance for respective Web systems, maintaining high customer service standards. Web Workload characterization and the analysis of Web log files are the basis on which Web server modeling for efficiency, scalability and availability can be planned. This thesis analyzes the Web access logs of six public Web sites: Department of Computer Science and Electrical Engineering at West Virginia University, West Virginia University, three NASA IVV servers, and Clarknet server. In addition, three private NASA IVV servers are also analyzed.;We characterize sessions using several attributes such as number of request per session, session length in time units, number of bytes transferred per session, and number of erroneous requests per session. We use clustering, as unsupervised learning methods, to classify Web server sessions. Unlike most other studies which were focused on building user profiles based on their navigational patterns, we use session attributes as basis for clustering. We also study the effectiveness of the Principal Component Analysis on session classification based on clustering
Role of histone methylation and variants in genome function
The eukaryotic genome is compacted in the form of chromatin, which is a complex of DNA and histone proteins. Regulation of chromatin structure influences all aspects of cellular processes, especially the DNA -dependent processes. The basic unit of chromatin is composed of DNA wrapped around a core of octameric histones, forming what is called the nucleosome core particle. The dynamic nature of this structure implies that there will be well-regulated processes and pathways that help in the interchanges between one form of chromatin and another. In chapter 1, I outline the current state of literature for mechanisms that regulate chromatin structure, with special emphasis on histone modifications and histone variants. I also review the literature for genome maintenance and how chromatin regulates genomic integrity. One of the most critical histone modifications that regulate chromatin structure is the methylation of histone H3 at lysine 36 (H3K36me). Set2 catalyzes H3K36me and its function is well established in regulation of chromatin structure during transcription elongation, but its function in maintaining the integrity of yeast genome was not known. In chapter 2, I describe its novel function in regulating chromatin structure after double strand break (DSB). Work from chapter 2 reveals that Set2-dependent H3K36me (2/3) and its interaction with RNA polymerase II (RNAPII) is critical for surviving DSBs after phleomycin. It also shows that H3K36me is critical for full activation of a DSB checkpoint. Furthermore, I show that H3K36me is also important for chromatin remodeling around a DSB, abrogation of which subsequently facilitates inappropriate end-processing. In chapter 3, I describe our ongoing efforts to delineate the dynamic incorporation/eviction of the histone variant Htz1 in yeast. I show that deletion of NAP1 and CHZ1 results in increased retention of Htz1 in yeast chromatin, and show that there are two non-overlapping surfaces on the Htz1-H2B nucleosome. Furthermore we show that specific point mutations of these residues have biochemical and biological effects on cells. In chapter 4, I describe the implications of my research, place it in the wider context of chromatin research and discuss the contribution of H3K36me and Htz1 in tumorigenesis.Doctor of Philosoph
A phytochemical and pharmacognostic approach of Ficus hispida Linn: a review
Herbal plants are arguably poised for a comeback as like sources of ethnic health products in the main due after their vast desire in accordance with synthesize complicated combinations on structurally diverse compounds, which ought to furnish a safer than more holistic approach in conformity with disease cure and prevention. Ficus hispida (FH) Linn belonging to the family Moraceae, who have various pharmacognostic properties. The class Ficus constitutes a necessary crew on trees, now not solely concerning their extensive medicinal virtue however also of their growth habits yet religious significance. Almost every part over those plants is ancient as a traditional belief on treatment because of the treatment on a variety of ailments through Indian traditional healers. The goal on the existing instruction is to accumulate competencies over ethno-medicinal and pharmacognostic importance about FH. FH includes extensive sorts on bioactives compounds as alkaloids, proteins and amino acids, carbohydrates, flavonoids, sterols, phenols, glycosides, gums and mucilage, saponins and terpenes. Multiple scientific researches have been published to establish the scientific foundation over common medicinal values attributed in conformity with FH of terms on ayurvedic usage the plant for blood disorders, anemia, dysentery, hemorrhoids, stomatorrhagia, jaundice and ulcers. The crop fruits are used namely aphrodisiac, lactagogue, emetic and tonic. Furthermore, pharmacological activities like anticancer, antioxidant, hepatoprotective, cardioprotective, anti-inflammatory have been additionally acknowledged recently. Till now, no action has been published in conformity with elaborate the pharmacognostic functions of FH Linn. The existing decrial is, therefore, an endeavour to relinquish a clear estimate of its pharmacognosy and phytochemistry and a considerable survey over its pharmacological activities
Anti-inflammatory activity of methanolic extract of Ficus hispida dried fruit
Background: Natural products are a valuable resource of novel bioactive metabolites and these products exist in which the anti-inflammatory activity. The present investigation studies the in vivo and in vitro anti-inflammatory activity of methanolic extract of Ficus hispida in rat’s model.Methods: Plant material was extracted with methanol in a Soxhlet extraction apparatus. Indomethacin was used as a standard drug here, which is a known potent inhibitor of PG synthesis. The carrageenin and histamine induced paw oedema were selected to represent models of acute inflammations. The test compounds and standard drugs were administered orally. After 60 minutes paw oedema was induced by giving 0.1 ml of 1% Carrageenan and 0.1 % histamine by sub-plantar administration. Paw volume-Plethysmometer by mercury displacement method, before and after 1 hr to 4 hours of carrageenan and histamine administration. Performed MTT-based cytotoxicity assay of the Ficus hispida on the RAW264.7 cell line to determine the IC50 and calculate the pro-inflammatory cytokines viz, IL-6, IL-1β and TNF-α and compared to the LPS control.Results: The result obtained from the in-vivo study shows that the Ficus hispida has significant anti- inflammatory activity in a dose dependent manner. This effect is similar to that produced by NSAIDS such as Indomethacin. The concentrations of IL-6, IL-1β and TNF-α, secreted by the cells after challenging with bacterial LPS (2 µg/ml) and subsequent treatment with 50 µg Ficus hispida has been found to reduce the production of all the three pro-inflammatory cytokines viz, IL-6, IL-1β and TNF-α as compared to the LPS control. The activity, in fact, is comparable to the standard NSAID Indomethacin.Conclusions: All these findings and phytoconstituents present in the extract could be the possible chemicals involved in the prevention of inflammations
Clinical presentation and bacteriological profile of diabetic foot in Eastern Bihar, India
Background: Diabetes is a worldwide problem. A majority of diabetic patients develop foot ulcers in one point of time or other during the course of their illness. Chronic wound, especially non-healing types are the most common surgical conditions. The etiopathogenesis of diabetic foot lesions are multi-factorial like diabetic neuropathies, vasculopathy, poor control of diabetes and bacterial infection. The aim of the present study was to study various modes of presentation and microbiological profile in management of diabetic foot.Methods: 100 diagnosed cases of diabetic foot were studied over a period of three years in the department of General Surgery at Katihar Medical College with emphasis on clinical features and microbiological picture of diabetic foot and its complications.Results: Males are more prone to surgical complications three times than females because of more outdoor activities. It is more prevalent in age group 51-60 years (36%). In the present study, cases presenting with ulcer were maximum (52%) followed by cellulitis (20%), cases presenting with gangrene of toe or foot was minimum (12%). Staphylococcus Aureus was found in majority of cases of septic lesions on culture of pus (41%). Other organisms isolated were Pseudomonas, Klebsiella, E.Coli, Proteus etc.Conclusions: Diabetic foot has varied presentation. The prevalence of diabetes mellitus and its surgical complications can be attributed to poor patient knowledge, education and awareness of the disease. Patient education for care of feet such as pairing of nails, wearing proper footwear and prompt reporting to doctor in case of early lesions is essential.
Doxorubicin induced histomorphometric changes in testes of albino rat
Anticancer drugs like doxorubicin have been found to affect male gonads thereby leading to infertility. This study was conducted to evaluate the effects of doxorubicin over short, mid and long term on testes of male albino rats. Sixty male albino rats aged 6-8 weeks were taken for study. The rats were randomly divided into 3 groups of experimental (each group containing 10 rats) and 3 groups of control (each group containing 10 rats). The experimental groups were given a single dose of doxorubicin i.e. 10 mg/kg body weight intra-peritoneally and sacrificed after 3 different duration for each group (second week, eighth week and sixteenth week). All rats under 3 control groups were given a single intra-peritoneal dose of 2.5 ml/kg body weight normal saline and sacrificed with their respective experimental groups. Significant difference in diameters (p=0.029) and cross-sectional area (p=0.028) of seminiferous tubules was observed between short term experimental and short term control rats. For both between midterm experimental and midterm control group, and between long term experimental and long term control group, a significant difference in right testis weight (p<0.001 for both), left testis weight (p<0.001 for both), volume of testis (p<0.001 and p=0.038), diameter (p<0.001 for both) and area (p<0.001 for both) of seminiferous tubules was observed. As compared to short term experimental group, midterm experimental group and long term experimental group had significantly lower right testis weight (p<0.001 for both), left testis weight (p<0.001 for both), diameter of seminiferous tubule (p<0.001 for both) and cross-sectional area of seminiferous tubule (p<0.001 both). Cross-sections of the seminiferous tubules of all the control groups had normal architecture. However, there was progressive destruction of seminiferous tubules structure across the experimental groups. Doxorubicin has deleterious effect on seminiferous tubules of albino rat testis.Nepal Journal of Biotechnology. Dec. 2015 Vol. 3, No. 1: 10-1
Pressure Induced Hydrogen Order–Disorder Transition in β-Ni(OH)2
Here we address the challenging problem of pressure induced hydrogen sublattice disordering in layered hydroxides using synchrotron X-ray powder diffraction (XRPD) and first-principles calculations..
An RNA polymerase II-coupled function for histone H3K36 methylation in checkpoint activation and DSB repair
Histone modifications are major determinants of DNA double-strand break (DSB) response and repair. Here we elucidate a DSB repair function for transcription-coupled Set2 methylation at H3 lysine 36 (H3K36me). Cells devoid of Set2/H3K36me are hypersensitive to DNA-damaging agents and site-specific DSBs, fail to properly activate the DNA-damage checkpoint, and show genetic interactions with DSB-sensing and repair machinery. Set2/H3K36me3 is enriched at DSBs, and loss of Set2 results in altered chromatin architecture and inappropriate resection during G1 near break sites. Surprisingly, Set2 and RNA polymerase II are programmed for destruction after DSBs in a temporal manner – resulting in H3K36me3 to H3K36me2 transition that may be linked to DSB repair. Finally, we show a requirement of Set2 in DSB repair in transcription units – thus underscoring the importance of transcription-dependent H3K36me in DSB repair
Efficacy of bioresorbable plating system in the treatment of pediatric maxillary fractures:A short clinical study
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