Prodigiosin, is a natural red pigment produced by various bacteria that firstly
characterized from Serratia marcescens. It is an alkaloid secondary metabolite with
a unique tripyrrol structure.This pigment is a promising drug owing to its reported
characteristics of having antifungal, immunosuppressive and anti-cancer activity. In
this study prodigiosin was produced by Serratia marcescens., which was isolated
from soil identified and characterized by morphology, Gram’s staining, biochemical
and carbohydrate fermentation tested and confirmed by the API 20E test.
From these samples, six isolates of Serratia marcescens( 24) % were obtained out
of 25 soil samples. Ability of these isolates in prodigiosin production was examined
to select the efficient isolate in prodigiosin production.Results showed that all of
these isolates are prodigiosin producers, and among them one isolate was the most
efficient in prodigiosin production.
The apoptotic effect of the pigment was assessed in blood lymphocytes cells by
DNA fragmentation analysis assay collected from anticoagulated human blood ,
prodigiosin at all concentrations were significantly increased the percentage of
fragmented DNA of peripheral blood Lymphocyte cells compared to control. This
study reveals that Prodigiosin has possessed apoptotic property.
The Effect of Prodigiosin Extracted from Serratia marcescens on DNA Fragmentation of Human Peripheral Blood Lymphocytes Cells
Serratia marcescens
Prodigiosin
apoptosis
DNA Fragmentation
Human Peripheral Blood and Lymphocytes Cells
Publication Date
Wed Apr 25 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Different Estimation Methods for System Reliability Multi-Components model: Exponentiated Weibull Distribution
Exponentiated Weibull Distribution (EWD)
Reliability of multi-component Stress – Strength models R(s
k)
Maximum likelihood estimator (MLE)
Moment estimator (MOM)
shrinkage method (Sh)
Least Squares Estimator (LS)
Rank Set Sampling (RSS). and mean squared error (MSE).
In this paper, estimation of system reliability of the multi-components in stress-strength model R(s,k) is considered, when the stress and strength are independent random variables and follows the Exponentiated Weibull Distribution (EWD) with known first shape parameter θ and, the second shape parameter α is unknown using different estimation methods. Comparisons among the proposed estimators through Monte Carlo simulation technique were made depend on mean squared error (MSE) criteria
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Publication Date
Sat Oct 01 2016
Journal Name
Journal Of Theoretical And Applied Information Technology
Factors affecting global virtual teams’ performance in software projects
Today the trend is to perform software development work via distributed geographical area among team
individual or even as an organization. However
due to the global market and international presence of many companies
there is a need to implement a global virtual teams. The global virtual team members are gradually engaged in globalized business environments across space
time and organizational boundaries via information and communication technologies. A global virtual team relies on communication
collaboration
and information exchange are the most important criteria in global virtual teams’ operations. The purpose of this paper is to answer two research questions. The first research question is to identify the factors affecting global virtual teams’ performance. A systematic literature review was conducted to answer the first research question. The second research question is on what the rank of the factor affecting the global virtual teams’ performance according to their level of effect on global virtual teams’ performance. Online survey was conducted within 103 developers and IT managers from eight IT companies to answer the second research question. The Statistical Package for Social Science (SPSS 22) was used to analyze the collected data. In this study
we investigated factors that affect global virtual teams’ performance
factors considered include cultural differences
language problems
time-zone differences
team size
technical problems
lack of trust
lack of sufficient training
and ICT problems. Also the findings indicated that lack of sufficient training is the highest level of effect on global virtual teams’ performance. On the other hand
team size is the lowest level of effect on global virtual teams’ performance. © 2005 - 2016 JATIT & LLS. All rights reserved.
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