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Verma R.K.,Jadavpur University | Pal P.K.,Jadavpur University | Kandpal B.C.,IPEC Inc
ICCCCM 2016 - 2nd IEEE International Conference on Control Computing Communication and Materials | Year: 2017

In the 21st century, GFRP composites have been successfully substituted majority of the traditional engineering materials and widely used in manufacturing sectors. As there are a number of favorable properties associated with GFRP composites; but machining of GFRP is significantly different as compared to other engineering materials, because, GFRPs are non-homogeneous in nature (which consist of distinctly different phases), so that their machining operation is characterized by uncontrolled intermittent fiber fracture causing oscillating cutting forces and critical bending stresses, poor surface properties due to crushed fiber or resin pull out. For effective use of any machining process, it becomes important to find optimum parametric setting to achieve improved quality as well as increased productivity. In this present context, a case study on optimal machining parameters selection has been reported to ensure high productivity as well as satisfactory surface quality of machined glass fiber reinforced epoxy composites. Utility function based on Taguchi optimization approach has been proposed in this research. During GFRP drilling, fiber breakage, entry and exit delamination are encountered as the major issues leading to decrease in product quality and overall productivity of manufacturing processes and products. Taguchi L16, 4 level orthogonal array have been used to study the influence of various combinations of process parameters Present work aims to conduct a case experimental research on drilling of GFRP (epoxy) composites in order to select the most appropriate process parameter combination by utility theory based approach to ensure satisfactory process performance yields as well as hole quality. © 2016 IEEE.


Ivakhnenko O.P.,Kazakh-British Technical University | Ivakhnenko O.P.,IPEC Inc | Abirov R.,Kazakh-British Technical University | Logvinenko A.,Kazakh National Technical University
Energy Procedia | Year: 2015

Mineral deposit precipitation is encountered in oil and gas production and transportation causing obstruction of technological operations. It causes damage to hydrocarbon-producing formations including conventional and unconventional petroleum reservoirs. This study outlines approach for magnetic analysis some of the dominant varieties of petroleum mineral deposits (scales). The results show that the petroleum scales have distinct magnetic differences. They also establish three magnetic classes: diamagnetic, paramagnetic and ferrimagnetic scales. The majority of the hydrocarbon deposits containing Ca, Sr, Ba cations are diamagnetic. Therefore, magnetic susceptibility can be used to rapidly distinguish between different reservoir scales.


Retamal J.,University of Santiago de Chile | Retamal J.,Uppsala University Hospital | Bergamini B.C.,Federal University of Rio de Janeiro | Carvalho A.R.,Federal University of Rio de Janeiro | And 8 more authors.
Critical Care | Year: 2014

Introduction: When alveoli collapse the traction forces exerted on their walls by adjacent expanded units may increase and concentrate. These forces may promote its re-expansion at the expense of potentially injurious stresses at the interface between the collapsed and the expanded units. We developed an experimental model to test the hypothesis that a local non-lobar atelectasis can act as a stress concentrator, contributing to inflammation and structural alveolar injury in the surrounding healthy lung tissue during mechanical ventilation.Methods: A total of 35 rats were anesthetized, paralyzed and mechanically ventilated. Atelectasis was induced by bronchial blocking: after five minutes of stabilization and pre-oxygenation with FIO2 = 1.0, a silicon cylinder blocker was wedged in the terminal bronchial tree. Afterwards, the animals were randomized between two groups: 1) Tidal volume (VT) = 10 ml/kg and positive end-expiratory pressure (PEEP) = 3 cmH2O (VT10/PEEP3); and 2) VT = 20 ml/kg and PEEP = 0 cmH2O (VT20/zero end-expiratory pressure (ZEEP)). The animals were then ventilated during 180 minutes. Three series of experiments were performed: histological (n = 12); tissue cytokines (n = 12); and micro-computed tomography (microCT; n = 2). An additional six, non-ventilated, healthy animals were used as controls.Results: Atelectasis was successfully induced in the basal region of the lung of 26 out of 29 animals. The microCT of two animals revealed that the volume of the atelectasis was 0.12 and 0.21 cm3. There were more alveolar disruption and neutrophilic infiltration in the peri-atelectasis region than the corresponding contralateral lung (control) in both groups. Edema was higher in the peri-atelectasis region than the corresponding contralateral lung (control) in the VT20/ZEEP than VT10/PEEP3 group. The volume-to-surface ratio was higher in the peri-atelectasis region than the corresponding contralateral lung (control) in both groups. We did not find statistical difference in tissue interleukin-1β and cytokine-induced neutrophil chemoattractant-1 between regions.Conclusions: The present findings suggest that a local non-lobar atelectasis acts as a stress concentrator, generating structural alveolar injury and inflammation in the surrounding lung tissue. © 2014 Retamal et al.; licensee BioMed Central Ltd.


Singh A.P.,IPEC Inc | Varun,National Institute of Technology Hamirpur | Siddhartha,National Institute of Technology Hamirpur
Solar Energy | Year: 2014

In this present experimental investigation the effect of geometrical parameters of multiple arc shaped roughness element on heat transfer and friction characteristics of rectangular duct solar air heater having roughness on the underside of the absorber plate have been studied. The parameters were selected on the basis of practical considerations and operating conditions of solar air heaters. The experiments carried out encompasses Reynolds number (Re) in the range of 2200-22,000, relative roughness height (e/. D) range of 0.018-0.045, relative roughness width (W/. w) ranges from 1 to 7, relative roughness pitch (p/. e) range of 4-16 andarc angle (α) ranges from 30 to 75°. The thermo-hydraulic performance parameter was found to be best for relative roughness width (W/. w) of 5. © 2014 Elsevier Ltd.


Singh A.P.,IPEC Inc | Varun,National Institute of Technology Hamirpur | Siddhartha,National Institute of Technology Hamirpur
Experimental Thermal and Fluid Science | Year: 2014

Incorporating artificial roughness on the underside of the absorber plate is an established effective and economic method for improving the thermal performance of a solar air heater. The present experimental investigation is undertaken to analyze the effect of various geometrical parameters for multiple arc shape ribs on heat transfer and friction characteristics. The experiments carried out encompasses Reynolds number (Re) in the range of 2200-22,000, relative roughness height (e/. D) values of 0.018-0.045, arc angle (α) range of 30-75° and relative roughness width (W/. w) ranges from 1 to 7 and relative roughness pitch (p/. e) range of 4-16. Thorough experimentation has been conducted to accumulate data on heat transfer and friction characteristics of a rectangular duct roughened solar air heater. Utilizing these experimental data, correlations for Nusselt number and friction factor are also developed. © 2014 Elsevier Inc.


Paula F.L.,Escola Nacional de Saude Publica | da Fonseca M.J.M.,Escola Nacional de Saude Publica | de Oliveira R.V.C.,IPEC Inc | Rozenfeld S.,Ensp da FIOCRUZ
Revista Brasileira de Epidemiologia | Year: 2010

Objective: To describe the common characteristics of elderly people admitted to public hospitals of Niterói (RJ) due to falls. Methods: Cross-sectional study with 110 elderly patients (60 years and more) admitted to public hospitals in Niteroi - RJ, with fractures after falls. Data were collected by a multidimensional questionnaire. Multiple correspondence and cluster analysis were used to describe the characteristics of this population. Results: The results indicated four groups. The first group was formed by individuals with better physical conditions who did not have a hip fracture, were more independent, used to go out more than twice a week, had good vision, had a short hospital stay, and were discharged to their homes. There was a group with worse conditions including those who were less independent, had a long hospital stay (more than 30 days), and died at the hospital. A third group was formed by those who had had a hip fracture, had poor vision, and used to go out less than once a week. The fourth group was comprised of those who stayed in the hospital from 11 to 30 days and used to go out once or twice a week. Conclusions: The multiple correspondence analysis proved to be a good technique to identify subgroups with common characteristics, which provides tools for the creation of strategies for fall prevention programs.


Gupta G.,IPEC Inc | Gupta V.K.,IPEC Inc | Chandra M.,BIT
Advances in Intelligent Systems and Computing | Year: 2016

This paper presents a technical reviewon various watermarking techniques applied to different videos. In this paper watermarking techniques are categorized according to two domains: spatial domain and transform domain. These techniques are studied and research progress in both the techniques in the field of watermarking has been shown in this paper. A summary of various watermarking technique in both domain are also presented in tabular form which provides an overview about the recent research work going on about video watermarking. © Springer India 2016.


Clemmer L.,La Jolla Bioengineering Institute | Martins Y.C.,La Jolla Bioengineering Institute | Zanini G.M.,La Jolla Bioengineering Institute | Zanini G.M.,IPEC Inc | And 2 more authors.
Antimicrobial Agents and Chemotherapy | Year: 2011

The murine model of cerebral malaria (ECM) caused by Plasmodium berghei ANKA (PbA) infection in susceptible mice has been extensively used for studies of pathogenesis and identification of potential targets for human CM therapeutics. However, the model has been seldom explored to evaluate adjunctive therapies for this malaria complication. A first step toward this goal is to define a treatment protocol with an effective antimalarial drug able to rescue mice presenting late-stage ECM. We evaluated the efficacy of artemisinin, artemether, artesunate, and quinine given intraperitoneally once a day, and combinations with mefloquine, in suppressing PbA infection in mice with moderate parasitemia. Artemether, artesunate, and quinine were then evaluated for efficacy in rescuing PbA-infected mice with ECM, strictly defined by using objective criteria based on the presentation of clinical signs of neurological involvement, degree of hypothermia, and performance in a set of six motor behavior tests. Artemether at 25 mg/kg presented the fastest parasite killing ability in 24 h and fully avoided recrudescence in a 5-day treatment protocol. Artemether and artesunate were equally effective in rescuing mice with late-stage ECM (46 and 43% survival, respectively), whereas quinine had a poor performance (12.5% survival). Artemether caused a marked decrease in brain leukocyte accumulation 24 h after the first dose. In conclusion, artemether and artesunate are effective in rescuing mice with late-stage ECM and decrease brain inflammation. In addition, the described protocols for more strict clinical evaluation and for rescue treatment provide a framework for studies of CM adjunctive therapies using this mouse model. Copyright © 2011, American Society for Microbiology. All Rights Reserved.


Cabrales P.,La Jolla Bioengineering Institute | Zanini G.M.,La Jolla Bioengineering Institute | Zanini G.M.,IPEC Inc | Meays D.,La Jolla Bioengineering Institute | And 2 more authors.
American Journal of Pathology | Year: 2010

Brain hemodynamics in cerebral malaria (CM) is poorly understood, with apparently conflicting data showing microcirculatory hypoperfusion and normal or even increased blood flow in large arteries. Using intravital microscopy to assess the pial microvasculature through a closed cranial window in the murine model of CM by Plasmodium berghei ANKA, we show that murine CM is associated with marked decreases (mean: 60%) of pial arteriolar blood flow attributable to vasoconstriction and decreased blood velocity. Leukocyte sequestration further decreased perfusion by narrowing luminal diameters in the affected vessels and blocking capillaries. Remarkably, vascular collapse at various degrees was observed in 44% of mice with CM, which also presented more severe vasoconstriction. Coadministration of artemether and nimodipine, a calcium channel blocker used to treat postsubarachnoid hemorrhage vasospasm, to mice presenting CM markedly increased survival compared with artemether plus vehicle only. Administration of nimodipine induced vasodilation and increased pial blood flow. We conclude that vasoconstriction and vascular collapse play a role in murine CM pathogenesis and nimodipine holds potential as adjunctive therapy for CM. Copyright © American Society for Investigative Pathology.


Miranda L.H.M.,Institute Pesquisa Clinica Evandro Chagas IPEC | Conceicao-Silva F.,Instituto Oswaldo Cruz | Quintella L.P.,IPEC Inc | Kuraiem B.P.,Institute Pesquisa Clinica Evandro Chagas IPEC | And 2 more authors.
Comparative Immunology, Microbiology and Infectious Diseases | Year: 2013

Cutaneous lesions of feline sporotrichosis show high fungal load and are associated with severe disease and elevated zoonotic potential. The present study describes the histopathology and fungal load of the lesions in different clinical presentations of feline sporotrichosis. Cats with sporotrichosis were separated into groups L1, L2 and L3 (lesions in one, two and three or more locations, respectively) and subjected to skin biopsies for histopathology. Eighty-six cats were included in the study. Lesions were suppurative granulomatous in 84 cases and poorly formed granulomas were predominant. The well-formed granulomas were associated with group L1. The high fungal load was predominant in group L3 and in poorly formed granuloma cases and did not occur in well-formed granulomas cases. The good general condition was associated with low fungal load. These findings suggest that the fungal load control in animals with more localized lesions and well-organized response is linked with the improvement in the outcome of infected cats. © 2013 Elsevier Ltd.

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