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Search Results: 1 - 10 of 581932 matches for " D. A.;Borrely "
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Síntese e caracteriza??o de zeólita de cinzas de carv?o modificada por surfactante cati?nico
Fungaro, D. A.;Borrely, S. I.;
Ceramica , 2012, DOI: 10.1590/S0366-69132012000100013
Abstract: zeolite synthesized from coal fly ash was modified with different concentrations (2 and 20 mmol.l-1) of hexadecyltrimethylammonium bromide (hdtma-br). the non-modified zeolite (nmz) and surfactant-modified zeolites (smz) were characterized by x-ray fluorescence spectrometry, x-ray diffraction, fourier transform infrared spectroscopy (ftir), scanning electron microscopy, thermogravimetric analysis, among others. the sms presented negative charge probably due to the formation of a partial bilayer of hdtma on exchangeable active sites on the external surface of nmz. a decrease in surface area was observed for smz as compared to nmz indicating zeolite surface coverage with hdtma-br molecules. the crystalline nature of the zeolite remained intact after adsorption of surfactant and heating for drying. ftir analysis indicated that there were no significant changes in the structure of the zeolite after adsorption of surfactant.
Schistosomiasis Control Using Piplartine against Biomphalaria glabrata at Different Developmental Stages
Ludmila Nakamura Rapado,Alessandro de Sá Pinheiro,Priscila Orechio de Moraes Victor Lopes,Harold Hilarion Fokoue,Marcus Tullius Scotti,Joaquim Vogt Marques,Fernanda Pires Ohlweiler,Sueli Ivone Borrely,Carlos Alberto de Bragan?a Pereira,Massuo Jorge Kato,Eliana Nakano ?,Lydia Fumiko Yamaguchi ?
PLOS Neglected Tropical Diseases , 2013, DOI: 10.1371/journal.pntd.0002251
Abstract: Background Schistosomiasis is one of the most significant diseases in tropical countries and affects almost 200 million people worldwide. The application of molluscicides to eliminate the parasite's intermediate host, Biomphalaria glabrata, from infected water supplies is one strategy currently being used to control the disease. Previous studies have shown a potent molluscicidal activity of crude extracts from Piper species, with extracts from Piper tuberculatum being among the most active. Methods and Findings The molluscicidal activity of P. tuberculatum was monitored on methanolic extracts from different organs (roots, leaves, fruit and stems). The compounds responsible for the molluscicidal activity were identified using 1H NMR and ESIMS data and multivariate analyses, including principal component analysis and partial least squares. These results indicated that the high molluscicidal activity displayed by root extracts (LC50 20.28 μg/ml) was due to the presence of piplartine, a well-known biologically-active amide. Piplartine was isolated from P. tuberculatum root extracts, and the molluscicidal activity of this compound on adults and embryos of B. glabrata was determined. The compound displayed potent activity against all developmental stages of B. glabrata. Next, the environmental toxicity of piplartine was evaluated using the microcrustacean Daphnia similis (LC50 7.32 μg/ml) and the fish Danio rerio (1.69 μg/ml). The toxicity to these organisms was less compared with the toxicity of niclosamide, a commercial molluscicide. Conclusions The development of a new, natural molluscicide is highly desirable, particularly because the commercially available molluscicide niclosamide is highly toxic to some organisms in the environment (LC50 0.25 μg/ml to D. similis and 0.12 μg/ml to D. rerio). Thus, piplartine is a potential candidate for a natural molluscicide that has been extracted from a tropical plant species and showed less toxic to environment.
Introducing Intelligent Agents Potential into a competent Integral Multi-Agent Sensor Network Simulation Architecture Design  [PDF]
A. Filippou, D. A. Karras
Journal of Software Engineering and Applications (JSEA) , 2013, DOI: 10.4236/jsea.2013.67B008
Abstract:

During this research we spot several key issues concerning WSN design process and how to introduce intelligence in the motes. Due to the nature of these networks, debugging after deployment is unrealistic, thus an efficient testing method is required. WSN simulators perform the task, but still code implementing mote sensing and RF behaviour consists of layered and/or interacting protocols that for the sake of designing accuracy are tested working as a whole, running on specific hardware. Simulators that provide cross layer simulation and hardware emulation options may be regarded as the last milestone of the WSN design process. Especially mechanisms for introducing intelligence into the WSN decision making process but in the simulation level is an important aspect not tackled so far in the literature at all. The herein proposed multi-agent simulation architecture aims at designing a novel WSN simulation system independent of specific hardware platforms but taking into account all hardware entities and events for testing and analysing the behaviour of a realistic WSN system. Moreover, the design herein outlined involves the basic mechanisms, with regards to memory and data management, towards Prolog interpreter implementation in the simulation level.

Water Quality and Ecotoxicity Assessment in Surface Waters from Cubat?o River and Surroundings, S?o Paulo, Brazil  [PDF]
Vanessa Silva Granadeiro Garcia, Eduardo Toshio Domingues Matsushita, Letícia Cristina Alves Mesquita, Deborah Inês Teixeira Fávaro, Sueli Ivone Borrely
Journal of Water Resource and Protection (JWARP) , 2017, DOI: 10.4236/jwarp.2017.912096
Abstract: The monitoring of water bodies means the attempt of protecting vulnerable groups of organisms inhabiting streams and rivers. Industrial and domestic discharges may worsen the water quality and affect biological balance, structure and the functioning of the ecosystem. Cubat?o City, is one of the largest industrial centers in Brazil and in Latin America, where the constant discharge of effluents into Cubat?o River and its tributaries caused a degradation scenario in the hydrographic basin of the region. The objective of this study was to evaluate the acute and chronic effects of surface water from Cubat?o River and two of its tributaries (Perequê and Pil?es) by ecotoxicological assays. In addition, physical chemical parameters were analyzed. Ceriodaphnia dubia and Vibrio fischeri were exposed-organisms during the studied period. The study was conducted between 2010 and 2011 in four campaigns and nine sites along the basin of Cubat?o River. The ecotoxicity was measured by Vibrio fischeri bioluminescence, EC50 values ranging from 31.25% to 71.61%. In contrast, based on a bioequivalence t-test statistical analysis, the results obtained with Ceriodaphnia dubia revealed no toxicity in the sampling sites. A critical analysis of raw data of luminescence was carried out showing higher values during the 2nd campaign. From the numbers obtained for physical-chemical parameters P5 was far the worst due to chlorides, hardness and conductivity. From the Pearson correlation analysis carried out with toxicity to V. fischeri and the physical chemical parameters, the dissolved oxygen in water resulted in a moderate positive correlation. Sediment contamination was also demonstrated in the region.
Serum lipid growth curves for children and adolescents in predicting adult dyslipidemia (Data from the Slovak Lipid Community Study)  [PDF]
Roman Alberty,Dá?a Albertyová
Advances in Biological Chemistry (ABC) , 2013, DOI: 10.4236/abc.2013.35045
Abstract: Objectives: To create age-and sex-specific growth curves for serum lipids in Slovak children and adolescents, and to compare age-and sex-specific cut-off points with the currently recommended procedure using a single set of risk values for the whole child and adolescent population. Methods: Data were extracted from a cross-sectional Slovak Lipid Community Study conducted in 2005-2007; 873 healthy children and adolescents aged 7-18 years were selected for this study. Smoothed percentile curves were generated by LMS Pro software. Results: All lipid parameters (except for total cholesterol and LDL-cholesterol in girls) were higher in puberty than in adolescence, with the lowest serum lipids between the ages of 15 and 16 years. Mean triglyceride levels were higher in girls than in boys in all age groups. At the age of 18 years, about 19% boys and 25% girls had borderline and 6% boys and 15% girls had elevated total cholesterol. Elevated triglyceride levels were seen in 13% of boys and 11% of girls while abnormally low levels of HDL-cholesterol were found in 17% of boys and 10% of girls. Conclusions: The results of this study suggest that 1) age and gender play a strong role in lipid measurements in children and adolescents, 2) Slovak children and adolescents have a relative high proportion of abnormal lipid levels, and 3) age-and sex-specific cut-off points for serum lipids could be used to identify children and adolescents with an elevated risk of dyslipidemia in adulthood.
Evaluation of Onchocerciasis: A Decade of Post Treatment with Ivermectin in Zainabi and Ririwai Doguwa Local Government Area of Kano State  [PDF]
D. A. Sufi, Tukur Zainab
Advances in Entomology (AE) , 2015, DOI: 10.4236/ae.2015.31001
Abstract: Rapid Assessment Method (RAM) were carried out to assess the current situation of Onchocerciasis after repetition of annual community directed distribution of Ivermectin in Zainabi and Ririwai of Doguwa Local Government area of Kano State. Certain manifestations, like nodules, leopard skin and blindness, were used to measure the endemicity level in the community. The subjects of 30 - 50 years who are engaged in rural occupation, resident in that community, were examined for the presence of nodules, skin lesion and blindness. The common manifestation in both communities is nodules with 3 (3.40%) and 2 (3.44%). Leopard skin and blindness were found in Zainabi with 2 (2.27%) and 2 (2.27%). The manifestation of Onchocerciasis was found in older age groups of 49 - 70 and 50 - 69 respectively, which give an indication that the disease was eliminated in the community due to mass distribution of Ivermectin in the previously known endemic community. We recommend mass distribution of Mectizan in other identified endemic foci.
A Short Vector Solution of the Foucault Pendulum Problem  [PDF]
I. A. Ciureanu, D. Condurache
World Journal of Mechanics (WJM) , 2015, DOI: 10.4236/wjm.2015.52002
Abstract: The paper studies the motion of the Foucault Pendulum in a rotating non-inertial reference frame and provides a closed form vector solution determined by vector and matrix calculus. The solution is determined through vector and matrix calculus in both cases, for both forms of the law of motion (for the Foucault Pendulum Problem and its “Reduced Form”). A complex vector which transforms the motion equation in a first order differential equation with constant coefficients is used. Also, a novel kinematic interpretation of the Foucault Pendulum motion is given.
Performance of a 270 MW Gas Power Plant Using Exergy and Heat Rate  [PDF]
D. A. Aderibigbe, G. Osunbor
Energy and Power Engineering (EPE) , 2019, DOI: 10.4236/epe.2019.112002
Abstract: The performance of a 270 MW (9 × 30 MW) AES Corporation barge mounted gas turbine power plant in Nigeria is evaluated using the heat rate and entropy generation by the components of the plant to characterize the irreversibility in each component when operating at different loads between 90% and 25%. The power plants have the peculiarity that three of the plants were supplied by three (3) different Original Equipment Manufacturers (OEM); A, B and C. This study is sequel to the fact that the gas turbines were the first independent power plants in the country and after more than fifteen years of operation, it is reasonable to evaluate the performance of the major components. By analyzing the thermodynamic performance of these components, the study demonstrates the utility value of exergy efficiency as an important parameter in the evaluation of major components in a gas power plant. Exergy efficiency is shown to be an important parameter in ranking the power plant components, identifying and quantifying the possible areas of reduction in thermodynamic losses and improvement in efficiencies. A new relationship is derived to demonstrate the correlation between the exergy efficiency and the heat rate of a 30 MW gas power plant. The prediction of the derived relationship correlates well with the observed operational performance of the 30 MW power plants. The combustion chamber in each of the plants provides the maximum exergy destruction during operation. Its exergy efficiency is shown to exhibit good correlation with its energy efficiency and the plant rational exergy. The implication is that from an operational and component selection viewpoint in the specifications of a gas power plant, knowledge of the Heat Rate which is usually provided by the OEM is adequate to make a reasonable inference on the performance of some critical components of the plant.
The Role of Prophylactic Antibiotics for Percutaneous Procedures in Orthopaedic Surgery  [PDF]
A. Gulati, A. Dixit, D. M. Williamson
Surgical Science (SS) , 2011, DOI: 10.4236/ss.2011.26075
Abstract: Introduction This study investigates the current practice of surgeons in the United Kingdom with regards to their usage of prophylactic antibiotics for percutaneous orthopaedic procedures. Methods An electronic survey of 10 questions was devised and sent to all members of the British Orthopaedic Association. Three hundred and three replies were obtained (172 consultants, 131 trainees). Results Only half the numbers of orthopaedic surgeons would routinely use antibiotics for percutaneous K-wire fixation. Of the other half, 28% would never prescribe antibiotics and 22% would use them in special circumstances only. These ‘special circumstances’ were also not standardised. 92% of those who did prescribe antibiotics would administer single dose only and the majority (90%) would administer them during induction. There was no significant difference between trainees and consultants or between different orthopaedic procedures with regards to whether prophylactic antibiotics were prescribed or not. Discussion This survey highlights the split of opinion amongst practising orthopaedic surgeons as to the necessity or otherwise of antibiotic prophylaxis in percutaneous orthopaedic procedures. There are no reliable guidelines and further work should be carried out to investigate this subject.
Estadio Candlestick Park, San Francisco (EE. UU.)
D'Amico, D. A.
Informes de la Construccion , 1978,
Abstract: The scope of the job is the enlargement of an existing base-ball stadium in order to increase by 50% its seating capacity and at the same time use the resulting larger field area to include an american foot-ball field. The adoption of a prefab concrete structure not only permitted to carry out the work at a faster pace, also the gradual opening to the public of the sections as they were being completed. The mounting of the structural elements by means of high capacity cranes permitted the construction work to proceed without interfering with the sports activities in the stadium during the three years that took to build the new area. Prefab concrete structure served also the purpose of giving the flnished work a sober feeling, yet lively, whiles at the same time allowing a high degree of functionality and a beauty hard to find in this type of buildings. Se trata de la ampliación de un estadio de baseball ya existente con el fin de aumentar en un 50% su capacidad de asientos y permitir, por otra parte, su conversión en estadio de rugby, aprovechando la superficie sobrante de la cancha de baseball, de mayor extensión. La adopción de una estructura prefabricada de hormigón posibilitó no sólo una aceleración notable de las obras, sino una habilitación progresiva de los tramos terminados para uso público. El procedimiento de montaje de los elementos estructurales mediante grúas de gran capacidad facilitó la no interferencia de las obras en el funcionamiento del estadio a lo largo de los 3 a os que duró su construcción. El hormigón prefabricado fue utilizado, además, para la obtención de un acabado sobrio y, a la vez, rico en movimientos, dotando al estadio, simultáneamente, de un alto grado de funcionalidad y una categoría estética difícil de encontrar en este tipo de edificios.
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