A modified generalized projective Riccati equation method

A modification of the generalized projective Riccati equation method is proposed to treat some nonlinear evolution equations and obtain their exact solutions. Some known methods are obtained as special cases of the proposed method. In addition, the method is implemented to find new exact solutions for the well-known Dreinfelds-Sokolov-Wilson system of nonlinear partial differential equations

Global Stability of Generalized Within-host Chikungunya Virus Dynamics Models

This paper proposes two models of a general nonlinear within-host Chikungunya virus (CHIKV) dynamics. The production, incidence, proliferation and removal rates of all compartments are modeled by general nonlinear functions that satisfy a set of reasonable conditions. The second model takes into consideration two forms of infected host cells: (i) latently infected cells which do not produce the CHIKV, (ii) actively infected cells which generate the CHIKV particles. We show that all the solutions of the models are nonnegative and bounded. The global stability of the steady states of the models is proven by applying Lyapunov method and LaSalle’s invariance principle. We perform numerical simulations to complement the obtained theoretical results

Ефективність використання засобів розосередженої генерації (відновлюваних та традиційних) для умов республіки Ірак

У статті зроблено спробу застосувати метод аналізу ієрархій для виявлення найбільш перспективних енерготехнологій генерування теплової та електричної енергії для умов республіки Ірак. Для аналізу взято вісім основних енерготехнологій і комплекс із семи критеріїв. Математичний апарат методу дає можливість визначити рівень перспективності, опираючись на паспортні дані енерготехнології та експертні оцінки фахівців.The article attempts to use the method of analytic hierarchy process to determine the most promising energy technologies generate heat and electricity for the conditions of the Republic of Iraq. For the analysis taken eight major energy technologies and a complex of seven criteria. The mathematical apparatus of the method makes it possible to determine the level of prospects based on the passport data of energy technologies and expert judgments.В статье предпринята попытка использовать метод анализа иерархий для определения наиболее перспективных энерготехнологий генерации тепловой и электрической энергии для условий республики Ирак. Для анализа взяты восемь основных энерготехнологий и комплекс из семи критериев. Математический аппарат метода дает возможность определить уровень перспективности опираясь на паспортные данные энерготехнологии и экспертные оценки специалистов

Chemical Investigation of Some Capparis Species Growing in Egypt and their Antioxidant Activity

Capparis cartilaginea and C. deserti growing in Egypt were investigated for their glucosiolates and rutin content. From Capparis cartilaginea four isothiocynates were isolated and identified using GC and EI/MS techniques. These compounds were butyl isothiocyanate (1), 6-methylsulphonylhexyl isothiocyanate (2), 7-methylsulphonylheptyl isothiocyanate (3) and 5-benzylsulphonyl-4-pentenyl isothiocyanate (4). In addition to compounds (1) and (2), two other compounds were isolated and identified from Capparis deserti. These compounds are 3-methylthiopropyl isothiocyanate (5) and [11-(2-butenylthio)6-undecenyl isothiocyanate] (6). Compounds (1), (2), (5) and (6) are reported in this study for the first time from Capparis deserti. The main flavonoid component in the studied species was isolated and identified as rutin by comparing the data with those reported. Also, quantitative evaluation of rutin in the two species was carried out by TLC-densitometric analysis. The antioxidant activity was done using diphenylpicrylhydrazyl (DPPH) radical scavenging method. The butanol fraction from C. cartilaginea and C. deserti showed the highest antioxidant properties

Effect of a Perioperative, Cardiac Output-Guided Hemodynamic Therapy Algorithm on Outcomes Following Major Gastrointestinal Surgery A Randomized Clinical Trial and Systematic Review

Importance: small trials suggest that postoperative outcomes may be improved by the use of cardiac output monitoring to guide administration of intravenous fluid and inotropic drugs as part of a hemodynamic therapy algorithm.Objective: to evaluate the clinical effectiveness of a perioperative, cardiac output–guided hemodynamic therapy algorithm.Design, setting, and participants: OPTIMISE was a pragmatic, multicenter, randomized, observer-blinded trial of 734 high-risk patients aged 50 years or older undergoing major gastrointestinal surgery at 17 acute care hospitals in the United Kingdom. An updated systematic review and meta-analysis were also conducted including randomized trials published from 1966 to February 2014.Interventions: patients were randomly assigned to a cardiac output–guided hemodynamic therapy algorithm for intravenous fluid and inotrope (dopexamine) infusion during and 6 hours following surgery (n=368) or to usual care (n=366).Main outcomes and measures: the primary outcome was a composite of predefined 30-day moderate or major complications and mortality. Secondary outcomes were morbidity on day 7; infection, critical care–free days, and all-cause mortality at 30 days; all-cause mortality at 180 days; and length of hospital stay.Results: baseline patient characteristics, clinical care, and volumes of intravenous fluid were similar between groups. Care was nonadherent to the allocated treatment for less than 10% of patients in each group. The primary outcome occurred in 36.6% of intervention and 43.4% of usual care participants (relative risk [RR], 0.84 [95% CI, 0.71-1.01]; absolute risk reduction, 6.8% [95% CI, ?0.3% to 13.9%]; P?=?.07). There was no significant difference between groups for any secondary outcomes. Five intervention patients (1.4%) experienced cardiovascular serious adverse events within 24 hours compared with none in the usual care group. Findings of the meta-analysis of 38 trials, including data from this study, suggest that the intervention is associated with fewer complications (intervention, 488/1548 [31.5%] vs control, 614/1476 [41.6%]; RR, 0.77 [95% CI, 0.71-0.83]) and a nonsignificant reduction in hospital, 28-day, or 30-day mortality (intervention, 159/3215 deaths [4.9%] vs control, 206/3160 deaths [6.5%]; RR, 0.82 [95% CI, 0.67-1.01]) and mortality at longest follow-up (intervention, 267/3215 deaths [8.3%] vs control, 327/3160 deaths [10.3%]; RR, 0.86 [95% CI, 0.74-1.00]).Conclusions and relevance: in a randomized trial of high-risk patients undergoing major gastrointestinal surgery, use of a cardiac output–guided hemodynamic therapy algorithm compared with usual care did not reduce a composite outcome of complications and 30-day mortality. However, inclusion of these data in an updated meta-analysis indicates that the intervention was associated with a reduction in complication rate

Coupling of thermal cracking with noncatalytic oxidative conversion of ethane to ethylene

Homogeneous thermal cracking of ethane, which is an endothermic and hence energy-intensive process, was carried out in the presence of limited O<SUB>2</SUB> under different process conditions (at 600&#176;-850&#176;C; O<SUB>2</SUB>/ethane ratio of 0-0.2; H<SUB>2</SUB>O/ethane ratio of 0-3.3; and space velocity of 2,000-11,000 h<SUP>-1</SUP>). The influence of a sulfur additive in the feed and reactor material on the process performance was also investigated. Noncatalytic oxycarcking of ethane in the presence of limited O<SUB>2</SUB>, greatly enhances not only the total conversion of ethane but also the conversion of ethane by purely thermal cracking. This process also occurs at a much lower contact time than that required to achieve the same conversion for the thermal cracking process. Also, both the exothermic oxidative conversion and the endothermic thermal cracking of ethane occur simultaneously, which makes this process very energy-efficeint, with a drastic reduction in external energy requirement and coke formation. By manipulating the process conditions, particularly the temperature and O<SUB>2</SUB>/C<SUB>2</SUB>H<SUB>6</SUB> ratio, the overall process can be made almost thermoneutral, mildly exothermic, or mildly endothermic

Mathematical Model for Problem of Stresses in ThermoMagneto-Piezoelectric Material

In this paper, an analytical solution for the stresses in a homogeneous, transversely isotropic, piezo-thermo-elastic material has investigated. The generalized theories of thermo-elasticity have used to investigate the problem. The surface subjected to thermally insulated or isothermal and electrically shorted boundary conditions. Finally, in order to illustrate the analytical development, numerical solution has carried out piezo - thermo-elastic material. The corresponding simulated results of various physical quantities such as displacements and stresses have presented graphically