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Search Results: 1 - 10 of 263 matches for " Kasim Sakran Abass "
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A Method for Fast Assessment of OP/CB Exposure in the Japanese Quail (Coturnix coturnix japonica) Using Combined Esterases Enzyme Activity as Biomarkers
Kasim Sakran Abass
Enzyme Research , 2014, DOI: 10.1155/2014/812302
Abstract: The aims of this study were to investigate the presence of different esterase activities in plasma and liver for Japanese quail and to combine determination of both carboxylesterase and cholinesterase as biochemical biomarker in order to identify the effects of carbamate and organophosphate compounds exposure. Carboxylesterase exhibits larger sensitivity to carbamate and organophosphate compounds than to cholinesterase and is present at higher levels. This permitted nature and distribution of carboxylesterase or cholinesterase to be measured. One predominant toxicological form of enzyme level constant in its patterns of motivation and inhibition with cholinesterase was identified in plasma with an apparent Michaelis constant for butyrylthiocholine iodide of 0.394?mM. Carboxylesterase activity in liver was considered by its preferential hydrolysis of the S-phenyl thioacetate. A concentration dependent decrease of carboxylesterase and cholinesterase has demonstrated during in vitro incubation of malathion, parathion, and trichlorfon in the range 0.125–2?mM, while with methomyl was in the range 0.25–4?mM. When quail ( ) was exposed orally for 48?h to concentrations of carbamate or organophosphate compounds of 3–200?mg/kg, the percentage inhibition of cholinesterase was in each case larger than that of carboxylesterase and reached statistical significance ( ) at lower concentrations. 1. Introduction Enzymes that preferentially catalyse the hydrolysis of ester bonds are classified as esterase (EC 3.1) and generally classified into two subgroups, carboxylesterase (CbE; EC 3.1.1.1) and cholinesterase (ChE; EC 3.1.1.7), depending on their substrate specificity and behaviour towards some inhibitors [1, 2]. There are many esterase decreases among carbamate (CB) and organophosphate (OP) compounds, which are the most important in the agriculture and veterinary medicine to control insect invasion; these compounds exert their toxic effects through inhibiting esterase enzyme activities [3–5]. CB and OP compounds exert acute toxicity by inhibition ChE, a serine hydrolase found in neuromuscular junctions of birds (connects the nervous system to the muscular system via synapses) as well as in peripheral and central cholinergic synapses [6, 7]. This leads to susceptible types in overaccumulation of the excitatory neurotransmitter acetylcholine and subsequent hyperpolarisation of the postsynaptic membrane. Determination of CbE and ChE enzyme activities levels is a valuable, dose dependent means of monitoring exposure to CB and OP pesticides in animal models and other
Comparison of Two Storage Methods for the Analysis of Cholinesterase Activities in Food Animals
Kasim Abass Askar,A. Caleb Kudi,A. John Moody
Enzyme Research , 2010, DOI: 10.4061/2010/904249
Abstract: Cholinesterases (ChE) are specialized carboxylic ester hydrolases that catalyse the hydrolysis of choline esters. They are classified into either acetylcholinesterase (AChE) or butyrylcholinesterase (BChE). Determination of ChE in the tissues is the appropriate tool for the diagnosis of organophosphorus and carbamate exposures. In general, a significant inhibition was seen in both AChE and BChE activities after 6 months of freezing at ?80°C and after 3 months of freezing at ?20°C. Linear regression of mean AChE and BChE was observed in all individual samples during the months of the two freezing methods. Bland and Altman plot of the ratios of the two freezing methods have showen the mean difference between the two freezing methods to be 8.8, and SD was 144.7 and ?127.6 for upper and lower limits, respectively, for liver, while in muscle the mean difference was 1.5 and SD was 32.5 and ?28.9 for upper and lower limits, respectively. 1. Introduction Cholinesterases (ChE) are specialized carboxylic ester hydrolases that catalyse the hydrolysis of choline esters. Two types of ChE activity have been identified in mammalian tissues; these are distinguished according to their substrate specificity and sensitivity to the selective inhibitors. The first is acetylcholinesterase (AChE, EC.3.1.1.7), which is systematically called acetylcholine acetylhydrolase. Other names include true cholinesterase, specific cholinesterase, red blood cell cholinesterase, erythrocyte cholinesterase, and cholinesterase I. The second is butyrylcholinesterase (BChE, EC.3.1.1.8), referred to systemically as acylcholine acylhydrolase. Other names include pseudocholinesterase, nonspecific cholinesterase, plasma cholinesterase, serum cholinesterase, propionylcholinesterase, benzoylcholinesterase, and cholinesterase II [1–4]. The preferred substrate for AChE is acetylcholine (ACh), BChE prefers butyrylcholine (BCh), and propionylcholine (PCh) [1, 2, 5]. AChE and BChE serve a pivotal role in regulating nerve impulse transmission by rapid hydrolysis of the neurotransmitter ACh [6, 7]. AChE appears to be the predominate enzyme performing this function, since AChE catalysis the hydrolysis of ACh much more rapidly than BChE [6, 8]. At present, the most widely used method for the determination of ChE activity is the colorimetric method of Ellman et al. [9]. This is a simple, accurate, fast, and direct method of measuring ChE activity in blood and tissues. It is based on the reaction between thiocholine, which is one of the products of the enzymatic hydrolysis of the synthetic substrates
Autonomy and interdependence: quandaries in research ethics  [PDF]
Bolatito Lanre-Abass
Health (Health) , 2012, DOI: 10.4236/health.2012.44026
Abstract: The autonomy of research participants is crucial in research ethics without which it will be difficult to carry out research. Central to the concept of autonomy is the debate on whether the cultural norms of individuals (particularly women) should be given priority in settings where these norms require that researchers should go through male heads such as husbands and traditional leaders. This paper examines issues relating to the autonomy of women in research ethics. It highlights the far-reaching implications of autonomy for women participating in research using Islam as a religion and Africa as case studies. The paper takes a look at what obtains in Ghana and Nigeria as African countries with diverse religious sects highlighting at the same time the extent to which women are autonomous in some Islamic parts of India and Pakistan. The paper stresses that in spite of certain factors limiting the autonomy of women in Africa and Islam, there is need for a more robust account of autonomy. It takes a relational approach to autonomy concluding at the same time that the best way to do bioethics is to be culture-sensitive.
Stability of Production Planning Problem with Fuzzy Parameters  [PDF]
Samir Abdou Abass
Open Journal of Applied Sciences (OJAppS) , 2012, DOI: 10.4236/ojapps.2012.23028
Abstract: The traditional production planning model based upon the famous linear programming formulation has been well known in the literature. The consideration of uncertainty in manufacturing systems supposes a great advance. Models for production planning which do not recognize the uncertainty can be expected to generate inferior planning decisions as compared to models that explicitly account the uncertainty. This paper deals with production planning problem with fuzzy parameters in both of the objective function and constraints. We have a planning problem to maximize revenues net of the production inventory and lost sales cost. The existing results concerning the qualitative and quantitative analysis of basic notions in parametric production planning problem with fuzzy parameters. These notions are the set of feasible parameters, the solvability set and the stability set of the first kind.
Numerical Solution of Klein/Sine-Gordon Equations by Spectral Method Coupled with Chebyshev Wavelets  [PDF]
Javid Iqbal, Rustam Abass
Applied Mathematics (AM) , 2016, DOI: 10.4236/am.2016.717167
Abstract: The basic aim of this paper is to introduce and describe an efficient numerical scheme based on spectral approach coupled with Chebyshev wavelets for the approximate solutions of Klein-Gordon and Sine-Gordon equations. The main characteristic is that, it converts the given problem into a system of algebraic equations that can be solved easily with any of the usual methods. To show the accuracy and the efficiency of the method, several benchmark problems are implemented and the comparisons are given with other methods existing in the recent literature. The results of numerical tests confirm that the proposed method is superior to other existing ones and is highly accurate
Social Engineering Threat and Defense: A Literature Survey  [PDF]
Islam Abdalla Mohamed Abass
Journal of Information Security (JIS) , 2018, DOI: 10.4236/jis.2018.94018
Abstract: This article surveys the literature on social engineering. There are lots of security application and hardware in market; still there are several methods that can be used to breach the information security defenses of an organization or individual. Social engineering attacks are interested in gaining information that may be used to carry out actions such as identity theft, stealing password or gaining information for another type of attack. The threat lies with the combinations of social engineering with another type of attacks like Phishing and Watering hole attack which make it hard to defense against. This research aims to investigate the impact of modern Social Engineering on the organization or individual. It describes the categories of Social Engineering, and how the attacker takes advantage of human behavior. At the same time, I also discuss the direct and indirect attack of social engineering and the defense mechanism against this attack.
Microstructure and Strength of Diffusion Bonded 2014 AA Alloys Using Copper Interlayer  [PDF]
Abass Ali Saleh
Open Journal of Applied Sciences (OJAppS) , 2019, DOI: 10.4236/ojapps.2019.95028
Abstract: The major awkwardness when joining AA2014 lies in the presence of creation of oxide films and brittle intermetallic in the bond region. However, diffusion bonding can be used to join these alloys without much difficulty. This paper reveals the characterization of diffusion connection of aluminum alloy AA 2014 with and without applying copper powder. Joining was achieved in vacuum up to (1 × 10-5 mbar) by means of vacuum system. Aluminum alloy AA2014 samples were done as cylinder form and interlayer thickness was equal 100 μm, under joining conditions of (325°C - 475°C) and 4 MPa and period of (1 hour). The ultimate strength was found equal to 188.36 MPa. Bonding joint was examined using light microscope, (SEM) with (EDS) for determining microstructure and depth of diffusion and microhardness was also used at connection zone. XRD outcomes display that the main intermetallic compound phase formula was Al2C. The maximum depth of diffusion obtained was 19.1 μm.
Universal Current-Mode Biquad Employing Dual Output Current Conveyors and MO-CCCA with Grounded Passive Elements  [PDF]
Kasim Karam Abdalla
Circuits and Systems (CS) , 2013, DOI: 10.4236/cs.2013.41013
Abstract:

A new universal multiple input multiple output (MIMO) type current-mode biquad employing two dual output current conveyors (DOCCII), one multiple output current controlled current amplifier (MOCCCA) and four passive grounded elements is proposed which can realize all the five basic filtering functions namely, low-pass (LP), high-pass (HP), band-pass (BP), band-stop (BR) and all-pass (AP) in current mode from the same configuration. The centre frequency\"\" can be set by the passive elements of the circuit and the quality factor Q0 is electronically tunable through bias currents of the MOCCCA. Therefore, the biquad filter has independent tenability for the\"\" and Q0. The active and passive sensitivities of Q0 and\"\" are low. The workability of the new configuration has been demonstrated by PSPICE simulation results based upon a CMOS CCII in0.35μm technology.

Optical and Morphological Studies of Chemical Bath Deposited Nanocrystalline Cd1-xZnxS Thin Films  [PDF]
Kasim Uthman Isah
Materials Sciences and Applications (MSA) , 2013, DOI: 10.4236/msa.2013.45036
Abstract:

Cadmium Zinc Sulfide, Cd1-xZnxS thin films were deposited by chemical bath deposition technique at bath temperature of 75°C. The morphology of the films was analyzed by scanning electron microscope, the optical constants of the films were estimated from the transmission and reflection spectra of the films in the wavelength range of 300 - 900 nm. The films had a transmittance between 75% and 85% and optical band gap in the range 2.8 - 3.4 eV. The dependence of the refractive index of the films on the wavelength was investigated using the single oscillator model, from which the dispersion parameters were determined. The high frequency dielectric constant εL and the ratio of the carrier concentration to the effective mass N/m* were estimated based on the Spitzer and Fan model. Both εL and N/m* show a decrease in value with increase in Zinc

An Agent-based Architecture for Developing E-learning System
Hasan Al-Sakran
Information Technology Journal , 2006,
Abstract: From the perspective of e-learning view, it is important to deliver dynamic learning content and manage educational material in an efficient way. An e-learning system should present personalized optimal content to the user, anytime and anywhere and encourage collaborative learning. It should guide specific individuals to their most relevant community or communities of knowledge by exploring the materials that others in the community are viewing or reading and linking learners and with experts. The purpose of this study is to formulate a functional architecture that supports the above e-learning objectives using mobile agent technology. This architecture gives users the ability to collect, analyze, distribute and use e-learning knowledge from multiple knowledge sources. The mobile agent technology is particularly suitable for developing distributed e-learning systems because it supports intelligent and distributed storage, allows an optimal personalized e-learning environment and enhances modularity, reusability, flexibility and reliability.
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