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Search Results: 1 - 10 of 304461 matches for " K. D. Beheng "
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Aerosol-cloud-precipitation effects over Germany as simulated by a convective-scale numerical weather prediction model
A. Seifert, C. K hler,K. D. Beheng
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2012,
Abstract: Possible aerosol-cloud-precipitation effects over Germany are investigated using the COSMO model in a convection-permitting configuration close to the operational COSMO-DE. Aerosol effects on clouds and precipitation are modeled by using an advanced two-moment microphysical parameterization taking into account aerosol assumptions for cloud condensation nuclei (CCN) as well as ice nuclei (IN). Simulations of three summer seasons have been performed with various aerosol assumptions, and are analysed regarding surface precipitation, cloud properties, and the indirect aerosol effect on near-surface temperature. We find that the CCN and IN assumptions have a strong effect on cloud properties, like condensate amounts of cloud water, snow and rain as well as on the glaciation of the clouds, but the effects on surface precipitation are – when averaged over space and time – small. This robustness can only be understood by the combined action of microphysical and dynamical processes. On one hand, this shows that clouds can be interpreted as a buffered system where significant changes to environmental parameters, like aerosols, have little effect on the resulting surface precipitation. On the other hand, this buffering is not active for the radiative effects of clouds, and the changes in cloud properties due to aerosol perturbations may have a significant effect on radiation and near-surface temperature.
Scavenging processes of atmospheric particulate matter: a numerical modeling of case studies
Gon?alves, Fábio Luiz Teixeira;Beheng, Klaus Dieter;Massambani, Oswaldo;Vautz, Wolfgang;Klockow, Dieter;
Revista Brasileira de Meteorologia , 2010, DOI: 10.1590/S0102-77862010000400003
Abstract: below cloud scavenging processes have been investigated considering a numerical simulation, local atmospheric conditions and particulate matter (pm) concentrations, at different sites in germany. the below cloud scavenging model has been coupled with bulk particulate matter counter tsi (trust portacounter dataset, consisting of the variability prediction of the particulate air concentrations during chosen rain events. the tsi samples and meteorological parameters were obtained during three winter campaigns: at deuselbach, march 1994, consisting in three different events; sylt, april 1994 and; freiburg, march 1995. the results show a good agreement between modeled and observed air concentrations, emphasizing the quality of the conceptual model used in the below cloud scavenging numerical modeling. the results between modeled and observed data have also presented high square pearson coefficient correlations over 0.7 and significant, except the freiburg campaign event. the differences between numerical simulations and observed dataset are explained by the wind direction changes and, perhaps, the absence of advection mass terms inside the modeling. these results validate previous works based on the same conceptual model.
Critical Data Delivery Using TOPSIS in Wireless Body Area Networks  [PDF]
K. Suriyakrishnaan, D. Sridharan
Circuits and Systems (CS) , 2016, DOI: 10.4236/cs.2016.76053
Abstract: Technology development in the Wireless Sensor Network (WSN) has paved the way for body area network for remote health monitoring. For this purpose, a message or a data packet should be transmitted from the patient to the medical evaluator without any loss. In this work, Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) algorithm is implemented for Wireless Body Area Networks (WBAN) to deliver the message, based on the criticality of the pa- tient. Finally, we compare the results for both the real-time data and the simulated (random) values in terms of packet-size forwarding for different parameters such as Packet Delivery Ratio (PDR), Delay and Throughput. The result shows better performance in the real time value by using TOPSIS scheme in the WBAN. By improving the quality of service in body area networks, health monitoring system can be automated with good performance.
Expression of a Bacterial Chitinase (ChiB) Gene Enhances Resistance against Erysiphae polygoni Induced Powdery Mildew Disease in the Transgenic Black Gram (Vigna mungo L.) (cv. T9)  [PDF]
D. K. Das
American Journal of Plant Sciences (AJPS) , 2018, DOI: 10.4236/ajps.2018.98128
Abstract: To enhance the antifungal response of blackgram (Vigna mungo L.), transgenic plants were generated by transferring bacterial chitinase gene with a CaMV 35S promoter. The chopped multiple shoot cells developed on the cotyledonary node were transformed by Particle gun method. Thecalli were raised on the Murashige and Skoog (MS) modified media supplemented with 50 m·gl-1 kanamycin. The transformation efficiency was 13% approximately. The resultant shoot buds were selected and the antibiotic resistant transgenic plantlets were regenerated. The development of the transgenic plants from the shoot buds took about four to six months. The integration of the transgene was confirmed by PCR, RT-PCR, Southern and western blot analyses. The transgenic plants exhibited higher chitinase activity than the non-transformed ones. The chitinase activity was examined by native polyacrylamide in-gel assay. The transgenic plants showed fungal tolerance as evidenced by the delayed onset of the disease and smaller lesions following an in vitro inoculation of the powdery mildew pathogen (Erysiphae polygoni DC). The transgenic plants adapted well to the greenhouse and did not show any phenotypic alterations.
Efficacy of Bacterial Adaptation on Copper Biodissolution from a Low Grade Chalcopyrite Ore by A. ferrooxidans  [PDF]
. Abhilash, K. D. Mehta, Bansi D. Pandey
International Journal of Nonferrous Metallurgy (IJNM) , 2012, DOI: 10.4236/ijnm.2012.11001
Abstract: A low-grade ore containing ~0.3% Cu, remains unutilized for want of a viable process at Malanjkhand Copper Project (MCP), India in which copper is present as chalcopyrite associated with pyrite in quartz veins and granitic rocks. In order to extract copper from this material, bioleaching has been attempted on bench scale using Acidithiobacillus fer-rooxidans (A. ferrooxidans) isolated from the native mine water. The enriched culture containing A. ferrooxidans when adapted to the ore and employed for the bioleaching at 5% (w/v) pulp density, pH 2.0 and 25°C with three particle sizes viz.150 -76 μm, 76 - 50 μm and <50 μm, resulted in recovery of 38.31%, 29.68% and 47.5% Cu respectively with a maximum rise in redox potential (ESCE) from 530 to 654 mV in 35 days. Under similar conditions, the unadapted strains gave a recovery of 44.0% for <50 μm size particles with a rise in ESCE from 525 to 650 mV. On using unadapted bacte-rial culture directly in shake flask at pH 2.0 and 35°C temperature and 5% (w/v) pulp density (PD) for <50 μm size par-ticles, 72% Cu bio-dissolution was achieved in 35 days. Copper biorecovery increased to 75.3% under similar condi-tions with a rise in bacterial count from 1 × 107 cells/mL to 1.13 × 109 cells/mL in 35 days. The higher bio-recovery of copper with the adapted bacterial culture may be attributed to the improved iron oxidation (Fe2+ to Fe3+) exhibiting higher ESCE as compared to that of unadapted strains.
Parameters Estimation of an Electric Fan Using ANN  [PDF]
Himanshu Vijay, D. K. Chaturvedi
Journal of Intelligent Learning Systems and Applications (JILSA) , 2010, DOI: 10.4236/jilsa.2010.21006
Abstract: Electric Fans are very commonly used in the industries, domestic applications and in tunnels for cooling and ventila-tion purposes. Fan parameters estimation is an important task as far as the reliable operation of a fan system is con-cerned. Basically, a fan is mainly consisting of a single phase induction motor and therefore fan system parameters are essentially the electrical parameters e.g. resistances, reactances and some load parameters (fan blades).These parame-ters often change under varying operating conditions and the knowledge of these parameters is necessary to have opti-mum and efficient operation of the system. Therefore, fan system parameters are required to be estimated. Further, fan system parameters estimation is required to ensure the smooth system operation and to avoid any malfunctioning of the system during abnormal working conditions. In this paper, Artificial Neural Networks (ANN) approach has been used for parameter estimation of a fan system. The simulated and experimental results are compared.
Cooperative binding of calcium ions modulates the tertiary structure and catalytic activity of Matrix-Metalloproteinase-9  [PDF]
Shakila Tobwala, D. K. Srivastava
Advances in Enzyme Research (AER) , 2013, DOI: 10.4236/aer.2013.12002
Abstract: To ascertain the molecular basis of Ca2+-mediated activation of matrix metalloproteinase-9 (MMP-9), we determined the accessibility of tryptophan residues to externally added acrylamide as quencher in the absence and presence of the metal ion. The steady-state and time resolved fluorescence data revealed that MMP-9 possesses two classes of tryptophan residues, “exposed” and “buried” which are quenched by the collisional rate constants (kq) of 3.2′ 109M-1.s-1 and 7.5′ 108M-1.s-1, respectively. These values are impaired by approximately two and three-fold, respectively, in the presence of 10 mM Ca2+. The Stern-Volmer constants (Ksv values) predicted from the time resolved fluorescence data (in the absence of Ca2+ ) satisfied the dynamic quenching model of the enzyme’s tryptophan residues. This was not the case in the presence of Ca2+ ; the steady-state acrylamide quenching data could only be explained by a combination of “dynamic” and “static” quenching models. A cumulative account of these data led to the suggestion that the binding of Ca2+ modulated the tertiary structure of the protein by decreasing the dynamic flexibility of the enzyme, which is manifested in further structuring of the enzyme’s active site pocket toward facilitating catalysis. Arguments are presented that the binding of Ca2+ at distal sites “dynamically” communicates with the
active site residues of MMP-9 during catalysis.


Phenolic Compositions of Litchi Shoot Tips and Zygotic Embryos Collected in Different Months and Their Effects on the Explant Browning and Its Control  [PDF]
D. K. Das, A. Rahman
Advances in Anthropology (AA) , 2016, DOI: 10.4236/aa.2016.64008
Abstract: In the research it was examined the changes in total phenolic contents and seven major phenolic compounds (gallic acids, +() catechin, catechol, Chlorogenic acid, o-coumaric acid, rutin and quercetin) of two litchi cultivars (Purbi and Bedana) shoot tips and fruits (for zygotic embryos) collected in different months, in order to determine their effects on the explants browning during establishment stage of shoot tip culture. The concentrations of phenolic compounds varied depending on the cultivars and the months. Phenolic compounds showed various correlation coefficients with the explants browning. Total phenolic content and some individual phenolic compounds including +() catechin, catechol, gallic acid, chlorogenic acid and rutin quantified in this study showed significant positive correlations with the explants browning, while o-coumaric acid and quercetin did not exhibit any significant one. According to our results, explants browning are affected by the phenolic compounds at different ranges. In both litchi cultivars, shoot tips and fruits (for zygotic embryos) collected in March exhibited the lowest explants browning during the establishment stage as compared to those collected in the other months. So it may be possible to increase the success of shoot tip and zygotic embryo culture with the selection of the most suitable terms of explants collection. Browning of explants could be controlled by the use of antioxidants both in semi-solid and liquid culture.
Translation and Validation of the Nepalese Version of Derriford Appearance Scale (DAS59)  [PDF]
Varun Pratap Singh, R. K. Singh, T. P. Moss, D. K. Roy, D. D. Baral
Modern Plastic Surgery (MPS) , 2013, DOI: 10.4236/mps.2013.32010
Abstract:

Objectives: To establish a valid and reliable translated version of Derriford Appearance Scale (DAS59) for Nepali population. Methods: A standard translation-back-translation procedure was used followed by evaluation of semantic, conceptual and society equivalence by the committee and changes were made according to recommendations. This corrected version was pretested and a final version was developed. A validation study was performed using the final version on 424 patients including 212 patients with clinical appearance problems and similar number of young adults who had no concern for facial appearance. Reliability was assessed by Cronbach’s alpha value and test-retest correlation coefficient. Discriminate and convergent validity were assessed by comparison between clinical and normal population and correlation with Beck’s Anxiety Inventory (BAI), Beck’s Depression Inventory (BDI) and General Health questionnaire (GHQ). Results: The results indicated excellent internal consistency (Cronbach’s alpha = 0.98) and good test-retest reliability (0.91 for clinical population, 0.86 for normal population). The Discriminate validity was good with statistically significant differences between clinical and normal population. The convergent validity was confirmed by good correlation with other related psychometric tools. Conclusion: A valid and reliable Nepali DAS59 version was developed which can be used for research and clinical assessment of patients with appearance problems and concerns.

Effect of abiotic factors on the molluscicidal activity of oleoresin of Zingiber officinale against the snail Lymnaea acuminata  [PDF]
Vijya Singh, Pradeep Kumar, V. K. Singh, D. K. Singh
Natural Science (NS) , 2010, DOI: 10.4236/ns.2010.210142
Abstract: Earlier it has been observed that oleoresin of Zingiber officinale is a potent molluscicide ag- ainst Lymnaea acuminata. This snail is the vector of Fasciola species, which cause ende- mic fascioliasis in eastern Uttar Pradesh. As this snail breeds and maintain their population constant through out the year, so that the present study has been designed to find out the effect of variations in some environmental factors in different seasons, on the molluscicidal activity of oleoresin of Zingiber officinale and its relative effect on certain enzymes viz., acetylcholinesterase, acid and alkaline phosphatases in the nervous tissue of the snail Lymnaea acuminata. In this study temperature, pH, dissolve oxygen, free carbon dioxide, conductivity of the water in control, as well as molluscicide treated water, was measured simultaneously. LC50 value of oleoresin was determined in each month of the year. Toxicity of oleoresin in June-July (24 h LC50 16.54-14.28 mgL-1) is highest. Acetylcholinesterase, acid and alkaline phosphatases activity in the nervous tissue of the snails treated with sub-lethal concentration of oleoresin was simultaneously measured. Sig- nificant positive rank correlation, in between the acetylcholinesterase or acid phosphatase activity and LC50 of oleoresin was observed. The pre- sent study conclusively shows that variant abi- otic factors can significantly alter the toxicity of oleoresin of Z. officinale in L. acuminata. The most suitable period for control of L. acuminata is June-July.
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