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Resonances for positron–helium and positron–lithium systems in kappa-distribution plasma
No full textS-wave resonances of positron-helium and positron-lithium systems in kappa-distribution plasmas are investigated using Hylleraas-type wave functions in the framework of the stabilization method. A model potential approach is used to represent the interactions between the outer electron, the positron and the core. The resonance parameters (position and width) of positron-helium and positron-lithium systems below the Ps(2s) threshold are reported as a function of screening parameter and spectral index of plasma
Socio-economic status and risk of tuberculosis: a case-control study of HIV-infected patients in Asia
No full textSETTING: Tuberculosis (TB) is the most common human immunodeficiency virus (HIV) related opportunistic infection and cause of acquired immune-deficiency syndrome related death. TB often affects those from a low socio-economic background. OBJECTIVE : To assess the socio-economic determinants of TB in HIV-infected patients in Asia. DESIGN: This was a matched case-control study. HIVpositive, TB-positive cases were matched to HIVpositive, TB-negative controls according to age, sex and CD4 cell count. A socio-economic questionnaire comprising 23 questions, including education level, employment, housing and substance use, was distributed. Socio-economic risk factors for TB were analysed using conditional logistic regression analysis. RESULT S : A total of 340 patients (170 matched pairs) were recruited, with 262 (77.1%) matched for all three criteria. Pulmonary TB was the predominant type (n = 115, 67.6%). The main risk factor for TB was not having a university level education (OR 4.45, 95%CI 1.50-13.17, P=0.007). Burning wood or coal regularly inside the house and living in the same place of origin were weakly associated with TB diagnosis. CONCLUS IONS : These data suggest that lower socioeconomic status is associated with an increased risk of TB in Asia. Integrating clinical and socio-economic factors into HIV treatment may help in the prevention of opportunistic infections and disease progression
Control of switch-sharing-based multilevel inverter suitable for photovoltaic applications
No full textOwing to the higher amount and the better quality of power transferred, three-phase multilevel inverters have strengthened their presence in low-power photovoltaic (PV) applications. However, the existing topologies investigated for low-power PV systems are basically meant for medium- and high-power applications, thus making them underutilized for low-power range. In order to address this shortcoming, this paper proposes a three-phase multilevel inverter with a switch-sharing capability and its control solution. It combines the characteristics of the two-level full-bridge topology and the diode-clamped multilevel structure. As a result, the inverter can be used with full capacity and without being underutilized, and significantly improves the output quality. A control strategy that is able to maximize the full potential of the inverter is developed. A digital proportional-integral (PI) controller with a new tuning algorithm is designed to effectively deal with the load changes. The result reveals that the load current is always retained at the intended quality level despite the variations in load. The performance of the inverter is validated from the experimental work conducted on a laboratory prototype under closed-loop conditions
Carbon dioxide induced degradation of diethanolamine during absorption and desorption processes
No full textAlkanolamines are widely used in the purification of the sour gas sweetening process. During the sour gas absorption process, CO2 significantly degrades the amine solvent and creates enormous problems for plant operation. In this work, CO2 induced degradation of aqueous diethanolamine (DEA) solution was conducted in a 1.25 L jacketed glass reactor that functioned as an absorber and stripper at atmospheric conditions. Pure CO2 was bubbled through the reactor until the solution became saturated. In this study, the concentrations of DEA used were in the range of concentrations between 2 mol·L− 1 and 4 mol·L− 1. In the degradation experiment, six generic cycles were conducted for each run. Each cycle was configured with the absorption and desorption of carbon dioxide at 55 °C and 100 °C, respectively. Samples were collected after a predetermined experimental time and analyzed by ion chromatography (IC) to identify unknown ionic degradation products (DGPs). In the IC analysis, three different columns were used for anion, cation and ion exclusion systems, which are Metrosep A Supp 5 150/4.0, Metrosep C Supp 4 150/4.0 and Metrosep Organic Acids, respectively. The major identified DGPs of D01DEA2M, D02DEA3M, and D03DEA4M are nitrite, acetate and ammonium. Phosphate product was found in the degraded amine samples which might be due to the contamination of water or chromatographic system
Usage of Model Driven Environment for the Classification of ECG features: A Systematic Review
No full textElectrocardiography (ECG) constitutes a perfect and primary diagnostic tool for measuring the different morbidity conditions of the heart in the context of different heart diseases and arrhythmia. Various studies have proposed different techniques of classification of ECG features and defined the parametric structure of different features of ECG. This paper is primarily designed to provide a more accurate classification by inducting the concept of a model-driven environment (MDE). Such induction works on the basis of reusable factors that are fitted to the state-of-the-art parametric structure of the ECG features. Some issues and challenges related to the embedding process are highlighted in the form of research questions. The aim of this paper is to provide the solutions to these research questions. The literature review is completed in two phases. In the first phase, those articles are collected that have been published in IEEE Xplore, ACM Library, Science Direct, and Springer, from 2008 to 2017.The second phase as a part of the execution stage is completed at the three different levels of the rectification process by adhering to the Kitchen ham guideline. At the first level, articles are filtered according to title and abstract. At the second level, articles are filtered according to specific eligibility criteria, and at the last level, articles are selected based on the skills of different domain experts (authors) by checking the quality assessment parameters. The significance of MDE in the classification of different ECG features is reflected in their compatibility with the research questions. Furthermore, future directions are proposed that depict the significance of dependencies involvement in classification analysis of ECG. These future directions are identified based on the planning and execution of our operational investigation and our critical observation of the existing gaps between dependencies of features classification that is the major cause of cardiovascular diseases
Gender Differences in Motivations for Identity Reconstruction on Social Network Sites
No full textSocial network sites provide people a unique opportunity for self-presentation. Due to various reasons, people may build an online identity that is partly or even completely different from their identity in the real world. Adopting social role theory as the theoretical foundation, the current study investigated gender differences in the motivations for virtual identity reconstruction on QQ, a social network site based in China. A total of 418 respondents participated in the study. As hypothesized, the results showed that men and women are motivated differently when reconstructing their identity–while women focus more on physical vanity, men emphasize achievement vanity. The authors also identified gender differences in other motivations for online identity reconstruction: bridging social capital, disinhibition, and privacy concerns. The results, which suggest that men and women behave in gender-specific ways, are in line with the propositions made in social role theory
Effect of Calophyllum Inophyllum biodiesel-diesel blends on combustion, performance, exhaust particulate matter and gaseous emissions in a multi-cylinder diesel engine
No full textIn this work, the effects of adding of inedible Calophyllum Inophyllum biodiesel to diesel fuel on performance, gaseous emissions, particulate matter (PM) and combustion characteristics were studied in a medium-duty, high-pressure common-rail turbocharged four-cylinder diesel engine under different speed and torque conditions. The key physicochemical properties of neat biodiesel, biodiesel-diesel blends and diesel were characterized and analysed. The test fuels used were a fossil diesel fuel, B10, B20, B30, and B50 of biodiesel-diesel fuels. The results indicated that all blends of biodiesel fuels have physicochemical properties relatively close to those of petroleum diesel. The experimental results also demonstrated that there are some drawbacks in engine brake power, brake specific fuel consumption (BSFC), and nitrogen oxide (NOx) with the blend of biodiesel in the fuel. Besides, refinement in brake thermal efficiency (BTE) and exhaust emissions were recorded across all engine speeds. Moreover, the emission improvement was characterized by lower carbon monoxide (CO) and reduced in both of the smoke and PM emissions. Also, reduction in the magnitude of peak combustion pressure and heat release rate (HRR) were also found with biodiesel blends. Overall, the results indicated that Calophyllum Inophyllum biodiesel can be used satisfactorily in an unmodified multi-cylinder high-pressure common-rail diesel engine
Molecular detection of Bartonella spp. In Malaysian small flying foxes (Pteropus hypomelanus)
No full textBartonella spp. are emerging zoonotic pathogens responsible for a wide variety of clinical syndromes in humans. Bats have been increasingly reported as reservoirs for Bartonella spp. In this study, molecular investigation showed the presence of Bartonella DNA in two of 30 blood samples of Malaysian small flying foxes (Pteropus hypomelanus). Two strains (Bartonella sp. KS013a and KS013b) were isolated from a PCR-positive blood sample after five days of incubation on blood agar. Based on the dendrogram constructed from 16S rRNA gene sequences, the two strains were genetically most closely related to ruminant associated Bartonella spp. Both strains are regarded as potentially novel Bartonella species as their citrate synthase (gltA) sequences exhibit less than 96% similarities to all previously identified Bartonella spp. Additionally, high gltA sequence similarity was observed between the strains with that reported from a bat fly (Cyclopodia horsfieldi) collected from P. hypomelanus. Possible transmission of Bartonella infection through bat flies and the impact of the infection in P. hypomelanus are yet to be investigated
Antibacterial effects of 18 medicinal plants used by the Khyang tribe in Bangladesh
No full textContext: The resistance of bacteria to antibiotics is raising serious concern globally. Asian medicinal plants could improve the current treatment strategies for bacterial infections. The antibacterial properties of medicinal plants used by the Khyang tribe in Bangladesh have not been investigated. Objective: The present study examines the antibacterial properties of 18 medicinal plants used by the Khyang tribe in day-to-day practice against human pathogenic bacteria. Materials and methods: Leaves, bark, fruits, seeds, roots and rhizomes from collected plants were successively extracted with hexane, ethyl acetate and ethanol. The corresponding 54 extracts were tested against six human pathogenic bacteria by broth microdilution assay. The antibacterial mode of actions of phytoconstituents and their synergistic effect with vancomycin and cefotaxime towards MRSA was determined by time-killing assay and synergistic interaction assay, respectively. Results and discussion: Hexane extract of bark of Cinnamomum cassia (L.) J. Presl. (Lauraceae) inhibited the growth of MRSA, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae andAcinetobacter baumannii with MIC values below 100 µg/mL. From this plant, cinnamaldehyde evoked at 4 × MIC in 1 h an irreversible decrease of MRSA count Log10 (CFU/mL) from 6 to 0, and was synergistic with vancomycin for MRSA with fractional inhibitory concentration index of 0.3. Conclusions: Our study provides evidence that the medicinal plants in Bangladesh have high potential to improve the current treatment strategies for bacterial infection
Application of the hybrid ANFIS models for long term wind power density prediction with extrapolation capability
No full textIn this paper, the suitability and performance of ANFIS (adaptive neuro-fuzzy inference system), ANFIS-PSO (particle swarm optimization), ANFIS-GA (genetic algorithm) and ANFIS-DE (differential evolution) has been investigated for the prediction of monthly and weekly wind power density (WPD) of four different locations named Mersing, Kuala Terengganu, Pulau Langkawi and Bayan Lepas all in Malaysia. For this aim, standalone ANFIS, ANFIS-PSO, ANFIS-GA and ANFIS-DE prediction algorithm are developed in MATLAB platform. The performance of the proposed hybrid ANFIS models is determined by computing different statistical parameters such as mean absolute bias error (MABE), mean absolute percentage error (MAPE), root mean square error (RMSE) and coefficient of determination (R 2 ). The results obtained from ANFIS-PSO and ANFIS-GA enjoy higher performance and accuracy than other models, and they can be suggested for practical application to predict monthly and weekly mean wind power density. Besides, the capability of the proposed hybrid ANFIS models is examined to predict the wind data for the locations where measured wind data are not available, and the results are compared with the measured wind data from nearby stations