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Arsenic is a major threat to large part of the population due to its carcinogenic nature. The toxicity of Arsenic varies with its chemical form and oxidation states. Glutathione (GSH), a major intra-cellular tripeptide plays a major role in arsenic detoxification. The present study was designed to provide insight into the extent of changes in GSH level by inorganic arsenic in the form of Arsenic trioxide (ATO) and organic arsenic in the form of nitro benzene arsenic acid (NBA). Lymphocytes (T.cells and B.cells) were investigated for determination of change in GSH metabolic status caused by arsenic. The depletion of GSH level positively correlated with increasing arsenic concentration and time of incubation. The decline in GSH level was consistent with increasing pH and physiological temperature. Our findings show that changes in GSH status produced by Arsenic could be due to adduct (As-(SG)3) formation. This change in GSH metabolic status provides information regarding mechanism of toxicity of inorganic and organic arsenicals. These findings are important for the rational design of antidote for the prevention of arsenic induced toxicity.

The design of an engine carburetor is traditionally based on a mechanical device that uses a shutter to control the amount of fuel intake. The fuel is mixed with air to form fuel mixture that is burnt in engine cylinders. This approach has several inherent issues. First, the shutter opening is controlled by creating a vacuum that results in required amount of fuel injected into carburetor chamber. As the speed of a vehicle increases by pressing accelerator, more fuel is required in the carburetor chamber. The rate of increase in fuel cannot be accurately calculated by a mechanical device. Second, the amount of air intake results in an imbalance in fuel mixture ratio. Third, the carburetor's efficiency degrades with age, resulting poor fuel efficiency. This paper proposes EFI for small vehicles. A test case was developed for a two-wheel motor-bike by using an ARDUINO board. The proposed solution was implemented in the engine of motor-bike with minor changes in the carburetor. The cost was quite comparable with mechanical carburetor, and the results were quite promising.

Metallo-elements have strong affinity for sulfhydryl group (-SH) of glutathione (GSH) present in tissues. It is very important and interesting to study the reaction of gallium nitrate and glutathione as biomarker of glutathione role in detoxification and conjugation in whole blood components (plasma and cytosolic fraction). The effect of gallium nitrate different concentrations was examined on GSH present in whole blood components. Decrease in GSH level was dependant on gallium nitrate concentration. The decrease in GSH level of whole blood components was more prominent with the time of incubation of gallium nitrate. Decrease in the concentration of reduced glutathione may be due to the interaction of reduce glutathione and gallium nitrate to form oxidized glutathione (GSSG) or gallium-glutathione complex. This change in GSH metabolic status provides information regarding the role of GSH in detoxification of gallium nitrate. The effect of gallium metal on glutathione in blood components was discussed in this study in in vitro condition as a model for in vivo condition. Key words: Gallium nitrate, reduced glutathione (GSH), whole blood, plasma, cytosolic fraction (CF), oxidized glutathione (GSSG), Di-thiobis- dinitro-benzoic acid (DTNB).

The denial of service (DOS) attack is a known problem in computer networks. This paper reviews DOS attack at the Application layer using session initiation protocol (SIP). Most of the existing solutions are based on adaptive threshold, cumulative sum, and Hellinger distance (HD). The HD uses number of INVITE messages for prediction of the possible flooding attack. A limitation of these approaches is that they all need training phase before actually being tested in the real situation. The proposed method proposes a completely different solution where transport layer protocol based on UDP is used to block the stream of undesired packets. This approach is novel and found to be working in various situations. The algorithm is rigorously tested using the network simulator NS2.

Purpose : To formulate and prepare controlled release (CR) matrix tablets of tramadol HCl using Carbopol 974P and 934 polymers as rate-controlling agents. Methods : The tablets were prepared by direct compression method using various drug to polymer (D:P) ratios. Co-excipients, including carboxymethylcellulose, starch and/or hydroxypropyl methylcellulose were also used to modulate the formulations. Various physical tests and in vitro dissolution studies were carried out on the formulations. The dissolution data were subjected to various release models Results : As the concentration of the polymer (rate-controlling agent) increased, dissolution rate decreased, For the formulation containing Carbopol 974P at D:P ratio of 10:7, drug release decreased to 83 % compared with the release rate of 99 % for the formulation with D:P ratio of 10:3. Kinetic analysis indicates that drug release mechanism was anomalous non-Fickian diffusion. Conclusion : Both Carbopol 974P and 934 can be used as rate-controlling agents in the formulation of tramadol HCl CR tablets. Appropriate selection of drug/polymer ratio can be applied effectively to modulate the dissolution rate of the drug. Keywords : Tramadol, Carbopol, Carboxymethylcellulose (CMC), Hydroxypropyl methylcellulose, Controlled release

Metallo-elements including Vanadium (V) have strong affinity for sulfhydryl (-SH) groups in biological molecules including Glutathione (GSH) in tissues. Because of this fact it was of interest to further investigate the interaction of Ammonium Vanadate [NH(4)VO(3)] with Glutathione as a biomarker of toxicity and the role of Glutathione in the detoxification and conjugation pr(o)Cesses in whole blood components including plasma and cytosolic fraction. Effects of different concentrations of Ammonium Vanadate [NH(4)VO(3)] on the level of reduced Glutathione in whole blood components (Plasma and Cytosolic fraction) were examined. GSH depletion in plasma and cytosolic fraction was Ammonium Vanadate's concentration-dependent. Depleted GSH level was more pronounced with more incubation time period. These findings show that changes in the GSH status produced by Ammonium Vanadate could be due to either by adduct formation of Vanadium and glutathione i.e. (V-SG) or by increased production of oxidized Glutathione (2GSH +V(+5) → GSSG). This change in GSH metabolic status provides some information regarding the mechanism of toxicity by Ammonium Vanadate and the protective role of glutathione.

The objective of the study was to formulate and evaluate sustained release polymeric tablets of ketoprofen for the release rate, release patterns and the mechanism involved in the release process of the drug. Formulations with three different types of newly synthesized polymers and one grade of ethyl cellulose ether derivatives (FP100 premium) in several drug-to-polymer ratios (D:P ratio 10:1, 10:2 and 10:3) were compressed into tablets using the direct compression method. They were examined for their physical properties and appearance. Tablets dimensional tests (thickness, diameter) and Q.C tests (hardness, friability, disintegration) were performed according to the USP methods. For in vitro drug release studies of Ketoprofen controlled release (CR) tablets, the USP Method-1 (Rotating Basket Method) was used with Pharma test dissolution apparatus (D-63512 Hainburg, Germany). The medium used for dissolution was phosphate buffer having a pH of 7.4 kept at constant temperature of 37±1°C. In order to analyze the drug release kinetics from each of the prepared matrices, five different mathematical models were applied to the release data including zero order kinetics, first order kinetics, Higuchi kinetics, Hixson Crowell kinetics and Korsmeyer Peppas equations were applied to the release data. The results obtained from different parameters showed that polymers: Polyglycolide, PGA-co-caprolactone, PGA-co-pentadecalactone and Ethocel FP100 premium can be used successfully in order to develop directly compressed prolonged release tablets of slightly soluble drugs such as ketoprofen. Particle size of polymer is a determining factor in controlling the release of ketoprofen from tablets. Ethocel standard FP100 polymers extend the release rates of drug more efficiently than the conventional granular form of the other three polymers. Further, the three new polymers and Ethocel FP100 could efficiently extend the release of the drugs as compared to the reference conventional formulation. Key words: Polymers, Ketoprofen, controlled-release preparations.

We report experimental evidence for a Rayleigh-Taylor-like instability driven by radiation pressure of an ultraintense (${10}^{21}\text{ }\text{ }\mathrm{W}/{\mathrm{cm}}^{2}$) laser pulse. The instability is witnessed by the highly modulated profile of the accelerated proton beam produced when the laser irradiates a 5 nm diamondlike carbon (90% C, 10% H) target. Clear anticorrelation between bubblelike modulations of the proton beam and transmitted laser profile further demonstrate the role of the radiation pressure in modulating the foil. Measurements of the modulation wavelength, and of the acceleration from Doppler-broadening of back-reflected light, agree quantitatively with particle-in-cell simulations performed for our experimental parameters and which confirm the existence of this instability.

The aim of the study was to formulate and evaluate topically applied ketoprofen gels and patches and to see the effect of naturally occurring almond oil as penetration enhancer on the penetration of ketoprofen through artificial membrane/rabbit skin. Prior to ketoprofen gel and patch formulation, the particle size and particle size determination of ketoprofen was analyzed by Particle size analyzer (Horiba LA300). Ketoprofen gels and patches were formulated and almond oil was added in several concentrations i.e. 0.5%, 1%, 1.5%, 2%, 2.5% and 3%. The formulated gels were evaluated by several parameters like pH, spreadibility, consistency, homogeneity, skin irritation and drug content determination. In vitro drug permeation studies from transdermal gels and patches were carried out across artificial membrane and rabbit skin by using Franz Cell Apparatus (PermeGear, USA). Kinetics model was employed to the release patterns of ketoprofen from gel and patches in order to investigate the drug transport mechanism. The cumulative amount of drug penetrated from different formulations was statistically evaluated by using One-way analysis of variance (ANOVA). Stability study was performed for various batches of ketoprofen transdermal gel. Almond oil as penetration enhancer in various concentrations significantly enhances the penetration of drug from transdermal gels and patch across synthetic membrane/rabbit skin but was most significant when used in 3% concentration.

Lead has been found to have the ability to interfere in the metabolism and biological activities of many proteins. It has also been found that metalloelements have strong affinity for sulfhydryl (-SH) groups in biological molecules including glutathione (GSH) in tissues. Because of these facts, it was of interest to investigate further the interaction of lead acetate [Pb (CH 3 COO) 2 ] with GSH as a biomarker of toxicity and the role of GSH in the detoxification and conjugation processes in whole blood components. Effects of different concentrations of Pb(CH 3 COO) 2 on the level of reduced GSH in whole blood components (plasma and cytosolic fraction) were examined. GSH depletion in whole blood components was lead acetate concentration dependent. Depleted GSH level was however more pronounced with time. These findings show that changes in the GSH status produced by Pb(CH 3 COO) 2 could be due to either by adduct (Pb-SG) formation or by increased production of oxidized glutathione (2GSH Pb+2 GSSG). This change in GSH metabolic status provides information regarding the mechanism of toxicity of Pb(CH 3 COO) 2 . These findings are therefore important for the rational design of antidote against the prevention of lead induced toxicity. Key words : Lead acetate, glutathione (GSH), dithiobisdinitrobenzoic acid (DTNB), plasma and cytosolic fraction (CF).

The objective of this study was to develop directly compressed oral controlled-release ibuprofen matrix tablets containing hydrophobic polymer (Ethocel®) of different viscosity gardes (Ethocel®standard 7P, 7FP, 10P, 10FP 100P and 100FP). As ibuprofen like other non-steroidal anti-inflammatory drugs has dosage frequency and severe gastrointestinal tract (GIT) complications and patient non-compliance, so to avoid these problems, controlled release matrices were developed. Before development of matrix tablets, pre-formulation studies were performed for the determination of physicochemical interaction between polymer, drug and co-excipients, using differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR) and no interaction was found. Controlled-release matrix tablets were formulated by direct compression method. Effect of partial replacement of lactose by different co-excipients such as HPMC K100M, starch and CMC on the release of drug was also studied. The tablets were subjected to different physicochemical, dimensional and quality controlled tests, such as drug content, weight variations, friability, hardness, thickness and diameter, all these tests were within United Stated Pharmacopoeia (USP) range. The in vitro release profile in phosphate buffer (pH 7.4) for all formulations containing polymer and co-excipients was compared with a formulation developed without polymer and co-excipients for 24 h. Different kinetics models were used, such as first-order equation, zero-order equation, Higuachi equation, Hixon Crowel’s equation and Korsmeyer-Peppas to study and investigate the release mechanism. It was concluded that formulations containing different grades of ethylcellulose polymer showed prolonged release for 6 to 18 h, but the formulation containing polymer Ethocel® standard FP7 premium without co-excipient showed controlled release for 24 h, which can be used to develop controlled release matrices of ibuprofen with optimum release kinetics. All those formulations containing co-excipients showed enhanced release rate. Key words: Ethocel® standard FP premium, Ethocel® standard premium, ibuprofen, matrix tablets, co-excipients, controlled release.

Silver nitrate (AgNO3) effect on the status of reduced glutathione (GSH), the major non-protein thiol in blood components were examined using freshly isolated plasma and cytosolic fraction of whole blood of healthy human volunteer. AgNO3 had significant effects on GSH contents reduction in plasma and cytosolic fraction of blood. Effect or reduction in GSH content was more pronounced or significant at AgNO3 concentration with time intervals (minutes to hours). Depletion of GSH in plasma and cytosolic fraction of blood by the addition of AgNO3 indicates that AgNO3 penetrated the cell membrane and reacted with GSH, depleted its contents mostly due to oxidation of reduced Glutathione (GSH) to glutathione disulphide (GSSG) 2 GSH-GSSG+2H+ or likely that AgNO3 after penetration formed a Silver-Glutathione (Ag-SG) complex. Time dependent effect of AgNO3 on the chemical status of glutathione was discussed in vitro in this paper which in principle presents the model of in vivo reaction, which will be the precise indirect impression of AgNO3 detoxification resulting by the interaction with GSH.

The experimental study of the behavior of deuterium plasma with densities between 2× 1018 and 2× 1020 cm-3, subjected to a 6 TW, 30 ps, 3× 1018 W cm-2 laser pulse, is presented. Conclusive experimental proof that a single straight channel is generated when the laser pulse interacts with the lowest densities is provided. This channel shows no small-scale longitudinal density modulations, extends up to 2 mm in length and persists for up to 150 ps after the peak of the interaction. Bifurcation of the channel after 1 mm propagation distance is observed for the first time. For higher density interactions, above the relativistic self-focusing threshold, bubblelike structures are observed to form at late times. These observations have implications for both laser wakefield accelerators and fast ignition inertial fusion studies. © 2010 American Institute of Physics.

The expansion of electromagnetic postsolitons emerging from the interaction of a 30? ps, 3×1018Wcm⊃-2 laser pulse with an underdense deuterium plasma has been observed up to 100? ps after the pulse propagation, when large numbers of postsolitons were seen to remain in the plasma. The temporal evolution of the postsolitons has been accurately characterized with a high spatial and temporal resolution. The observed expansion is compared to analytical models and three-dimensional particle-in-cell results, revealing a polarization dependence of the postsoliton dynamics. © 2010 The American Physical Society.

Lithium remains a mainstay in the acute and prophylactic treatment of bipolar affective disorder. It is used in the augmentation of antidepressant treatment and, less frequently, in the augmentation of antipsychotic treatment of schizophrenia. It is reported to have specific anti-suicidal effects. Thus the effect of Lithium was interesting to study on the glutathione (GSH) level in vivo conditions. Ellman's method has been used to see the effect of lithium on glutathione (GSH) level in whole blood. The time dependent effect of Lithium on the chemical status of glutathione (GSH) was determined in the whole blood (Plasma and cytosolic fraction) of human. The concentration of Glutathione was drastically decreased. The decrease in the glutathione level was concentration and time of interaction dependent, probably due to oxidation of glutathione (GSH) to corresponding disulphide (GSSG). In this paper the effect of Lithium on the Thiol/GSH level was discussed in vitro, which in principal may present a model of in vivo reaction.

In order to manage a project and bring it to a successful completion, its project manager must have a complete understanding of the methods being used for the management of different parts of the project. Managers prefer specific project methodology/framework, while resist and face difficulties for an opportunity to manage another project with different methodology or a framework as they don't know how much commonality exists between the preferred and the new required methodology/framework. The crux of this paper is to present an understanding for managers and their organizations which can really augment their overall performance by having an understanding of different dynamics of different project management methodologies/frameworks and then use this understanding intelligently either by combining different powerful features or simply by knowing the equivalency with competitors which are using other project management methodologies/frameworks. This paper can be a good resource for the project managers having difficulty in deciding which and why a particular project management methodology/framework should be opted. To parameterize the scope of this paper, five important project management methodologies/frameworks were compared with PMBOK, which is a growing and established project management methodology. Finally a conclusion with a generic project management approach has been suggested.

Environmental contamination with metals through indus-trial wastes is one of the major health concerns ofdeveloping countries. Metal pollutants can easily enter thefood chain if heavy metal-contaminated soils are used forproduction of food crops. Farm productivity has beendecreased in toxic metal polluted areas (Gosavi et al. 2004;Principi et al. 2006).Chromium (Cr) is the seventh most abundant element onthe earth crust (Katz and Salem 1994) and in waters orig-inates from natural sources, such as weathering and rockconstituents, wet precipitation and dry fallout from theatmosphere and runoffs from terrestrial ecosystem. How-ever, chromium discharges from industries such aselectroplating units, from leather tanning, metal finishingtextile, nuclear power plants and paper industry increasedits concentration in surface water several fold higher thanits natural occurrence. Chromium exists in two oxidationstates as Cr (III) and Cr (VI). The hexavalent form is 500times more toxic than the trivalent form (Kowalski 1994).It is toxic to microorganisms, plants, animals and humans.Human toxicity includes lung cancer, as well as kidney,liver, and gastric damage (US Department of Health andHuman Services 1991; Cieslak-Golonka 1995).Lead contamination in surface water mainly comes fromanthropogenic sources (96%), particularly from combus-tion of leaded fuels, pyrometallurgical non-ferrous metalproduction and coal combustion. Lead in natural watersmay be in the form of organic lead complexes originallyfrom the fuel of ever growing automobile population andsubsequent break down of tetraethyl lead (Monterroso et al.2003; Andrews and Sutherland 2004). The most seriouseffects of lead are related to impacts of central nervoussystem (Goyer 1993). It is considered a non-essential metalwith no biological role in microorganisms, animals andplants (Bruins et al. 2000).Microbial metal bioremediation is an efficient strategydue to its low cost, high efficiency and ecofriendly nature.Recent advances have been made in understanding metal–microbe interaction and their application for metal detox-ification. Ciliate protozoa are cosmopolitan eukaryoticmicroorganisms adapted for life in soils and aquatic eco-systems. They are believed to be important grazers ofbacteria and other microorganisms and in some artificialecosystems such as activated sludge wastewater treatmentplants, ciliates significantly improve effluent quality (Curds1982; Nicolau et al. 2001).One of the objectives of this study was to evaluate thesurvival of protozoa in media containing Cd

A ciliate protozoan, Euplotes mutabilis, isolated from heavy metal laden industrial wastewater, has been shown to tolerate multiple heavy metals thus suggesting its significance in bioremediation of industrial effluents. This ciliate tolerated Zn(2+) up to 33 microg/mL, Cd(2+) up to 22 microg/mL and Ni(2+) up to 18 microg/mL. The ciliate could uptake 85% Zn(2+), 84% of Cd(2+) and 87% of Ni(2+) after 96 h of inoculation of growth medium containing 10 microg/mL of Zn(2+) and 5 microg/mL of Cd(2+) and Ni(2+), with actively growing ciliates. After 6 days of incubation the ciliate removed 87% Cd(2+), 92% Ni(2+), and 93% Zn(2+) from the wastewater. The heavy metal uptake capability of Euplotes mutabilis may be employed for metal detoxification operations.

A wireless network provides a significant advantage over the traditional wired network. The primary advantage is in the convenience, and in quick to deploy arrangement in at places with limited supports. This additional benefit is however not easy to realize without looking in to several points that requires more stringent analysis. One of the significant factor due to its very nature, wireless communication more prone to an unauthorized access by a user who happens to be in the vicinity, and is able to break in the security barriers. Most of the authentication mechanisms that use shared key mechanism carry the risk of loosing key during key distribution, or during authentication process. During this the highest amount of risk is present at the access points. The current wireless networks are based on 802.11b wired equivalent privacy (WEP) protocol that is based on shared key authentication. The protocol was originally designed keeping requirements of a wired network. This works fine under normal conditions, but in special circumstances it fails to provide data security. This research proposes a new approach that is based on public & private key encryptions. Once a session is established, a key is generated of that particular session. This session key shall be used through out the communications. The proposed approach is implemented on a simulator. This approach, in our finding applies more stringent requirements that are much harder to break by an intruder

Parallel distributed computing systems provide mechanisms for exploiting parallelism inherent in many scientific and engineering applications. One such programming environment that has successfully demonstrated operation on a collection of heterogeneous computing elements incorporated by one or more networks is the parallel virtual machine (PVM). It has been used on high end computing resources such as mainframe computers, multiprocessors, hypercubes, and the like. In Pakistan, the most common computing resource is a low cost PC. The abundance of such machines provides an opportunity to develop and use a "poor man's supercomputer". In addition, research on PVM has focused on Unix or similar platforms. None of the formal results, to evaluate certain benchmark applications, are available on Windows-based environments. The work reports the results of the local PVM implementation and compares them with results from conventional implementations of PVM.

This paper proposed a systematic approach to select a mathematical model for an industrial heating system by adopting system identification techniques with the aim of fulfilling the design requirement for the controller. The model identification process will begin by collecting real measurement data samples with the aid of MATLAB system identification toolbox. The criteria for selecting the model that could validate model output with actual data will based upon: parametric identification technique, picking the best model structure with low order among ARX, ARMAX and BJ, and then applying model estimation and validation tests. Simulated results have shown that the BJ model has been best in providing good estimation and validation based upon performance criteria such as: final prediction error, loss function, best percentage of model fit, and co-relation analysis of residual for output.