209 research outputs found
Analysis of Inductance Gradient and Current Density Distribution Over Different Cross-section of Rails
In a rail gun system the armature accelerated due to the Lorentz force caused by the current which is diffused in to the rails. The entire system depends on the inductance gradient of the rail which is directly connected to the accelerating performance and efficiency of railgun. Hence, the exact analysis of inductance gradient is extremely significant for the railgun design. Since short duration of current pulse is applied to the rails determination of inductance gradient is very difficult. The inductance gradient varies with the geometric dimensions of the rails and armature. And it can be calculated with analytical method and numerical methods. In this paper inductance gradient of the rail has been computed and compared with the different rail cross-sectional models using Ansoft Maxwell Eddy current solver uses finite element technique to calculate the field distribution in a space. The current density, magnetic flux density, repulsive force acting on the rails also computed to analyze the performance of rail gun
Formulation and Optimization of Prolonged Release Buccal Patch of Melatonin
Melatonin is a hormone which is used for the treatment of chronic insomnia, jet lag and regulation of circadian rhythm. Since it has a very low oral bioavailability of less than 15% and very short half-life of less than 45 min, therefore mucoadhesive buccal patch formulation was investigated.
In the present work successful attempt was made to formulate prolonged release melatonin buccal patch by solvent casting method using hydrophilic polymers HPMC K4M, Carbopol 974P and Polyethylene glycol 400 as plasticizer. The drug polymer compatibility was verified by FT-IR studies. The standard curve of melatonin in pH 6.8 phosphate buffer was prepared.
A two factor and three-level factorial design was used to optimize the formulation, where concentration of HPMC K4M (X1) and Carbopol 974P (X2) taken as two independent variables and dependent variables were T50 (Y1), drug release at 8h (Y2), mucoadhesion time (Y3). Totally 9 trial buccal patches were prepared and evaluated for weight variation, thickness, drug content, folding endurance, swelling property, surface pH, percent moisture loss, ex vivo mucoadhesion time, in vitro dissolution test and ex vivo permeation study.
It was observed that increasing the HPMC K4M concentration has a significant increase in mucoadhesion time and decrease in drug release.
Then using the design expert software the optimized formulation was obtained. The best polymer composition was found to be HPMC K4M (629.74 mg) and Carbopol 974P (120 mg).
The optimized formulation shows satisfactory results in the parameters such as thickness, hardness, drug content, swelling index, mucoadhesion time, in vitro dissolution and diffusion studies. It shows zero order drug release profile depending on the regression value and shown required mucoadhesion time of 512 min as well as a satisfactory release of 92.59 % at 8h with good mechanical properties. A hydrophobic backing layer was attatched to the patch for unidirectional release. Slow, controlled and maximum release of melatonin over a period of 8 h was obtained from the optimized buccal patch.
Buccal delivery has been extensively investigated for both local and systemic therapy of various drug molecules by different delivery approaches. Currently, there are only few commercial formulations available or under clinical trials.
This low commercial success is probably due to the high production cost. Nevertheless, the recent technological advances in mucoadhesive presents new opportunities and is likely to pave way for several other molecules into clinical use. In this study, a full factorial (32) design was constructed to optimize the mucoadhesive buccal patch of melatonin.
The suggested formulation could successfully achieve prolonged drug release and maintain drug concentration required for inducing and maintaining sleep, which consequently enhance patient compliance
Exploring the perspectives of allied health practitioners toward the use of journal clubs as a medium for promoting evidence-based practice: a qualitative study
<p>Abstract</p> <p>Background</p> <p>Research evidence suggests that journal clubs (JCs) are one approach which can be used to bridge the gap between research and clinical practice. However, there are issues which potentially threaten their viability such as on-going participation or compliance with attendance, which require further exploration. The objectives of this study are: to explore the views and perspectives of allied health practitioners (AHPs) regarding the use of any type of JC in promoting evidence-based practice (EBP); to identify ways in which an innovative model of JC developed by the International Centre for Allied Health Evidence (<it>i</it>CAHE) might be refined.</p> <p>Methods</p> <p>A qualitative descriptive study utilising focus group interviews with various groups of AHP was undertaken-- those who have been exposed to the <it>i</it>CAHE JC model and those who have no experience of the <it>i</it>CAHE model (although they may have had exposure to other forms of JC). Maximum variation sampling was used to recruit participants for the study. Transcripts of focus groups were coded and distilled into content-related categories.</p> <p>Results</p> <p>Six focus groups with 39 AHPs were facilitated. Allied health practitioners perspectives' on JCs were classified in five broad categories: utility and benefits of a JC, elements of an effective and sustainable JC, barriers to participation, incentives for participation, and opportunities for improvement in the current <it>i</it>CAHE JC model. Overall, JCs were seen as a forum for reflective practice and keeping up-to-date with research evidence, and a venue for learning the processes involved in critical appraisal. Limited knowledge of statistics and heavy clinical workload were reported as barriers to participation in a JC. Strategies such as mentoring, strong support from managers, and providing CPD (continuing professional development) points can potentially address these barriers. Opportunities for refinement of the current <it>i</it>CAHE model were raised.</p> <p>Conclusions</p> <p>This study suggests that a structured model of JC such as <it>i</it>CAHE's model is acceptable, and likely to be used with enthusiasm by AHP to achieve EBP. Future research should explore the impact of <it>i</it>CAHE JC compared with no JC exposure, and other forms of exposure to JCs, in influencing change in allied health practitioners behaviours and evidence implementation.</p
Development of Needle Punched Non-woven Fabrics for Acoustic Application
Abstract: Acoustic insulation is an important requirement for the human life today, since noise affects the efficiency of day-to-day activities and even causes various health problems. Materials based on fibrous structures show very good acoustic insulation properties, which however strongly depends on the type of structures used. The present paper focuses on qualitative analysis of the acoustic insulation behaviour of various needle punched nonwoven fabrics. Non -woven fabric shows higher sound reduction than the woven fabric. Produced nonwoven fabric combinations of three types of recycled raw materials like polypropylene 50%, PET 20% and hollow PET 30% were taken blended. webs have been produced by needle punched nonwoven with three different stitch density (punches per square meter)) of 250 , 300 and 450 for the acoustic application. The results shows that the acoustic insulation is better in 250 SD needle punched nonwoven than the other samples. Also non woven made from recycled fibres like PET, hollow PET and polypropylene show better performance than the materials made from jute, wool and wood charcoal
Online Shopping In The UK
This paper will contribute to current academic literature in the area of online retailing and consumer behaviour. Our research outlines a survey conducted with respondents from the UK to ascertain their attitudes to grocery shopping both off and online. The findings indicate that, whilst the vast majority of our sample has experience of online shopping, few actively engage in online grocery shopping. Some of the reasons for this are highlighted and the key issues relate to consumer trust and confidence in both online and offline aspects of the service. If these issues are addressed, it is proposed that more people would be encouraged to shop for groceries online
Evaluation of Antiproliferative Activity of Red Sorghum Bran Anthocyanin on a Human Breast Cancer Cell Line (MCF-7)
Breast cancer is a leading cause of death in women worldwide both in the developed and developing countries. Thus effective treatment of breast cancer with potential antitumour drugs is important. In this paper, human breast cancer cell line MCF-7 has been employed to evaluate the antiproliferative activity of red sorghum bran anthocyanin. The present investigation showed that red sorghum bran anthocyanin induced growth inhibition of MCF-7 cells at significant level. The growth inhibition is dose dependent and irreversible in nature. When MCF-7 cells were treated with red sorghum bran anthocyanins due to activity of anthocyanin morphological changes were observed. The morphological changes were identified through the formation of apoptopic bodies. The fragmentation by these anthocyanins on DNA to oligonuleosomal-sized fragments, is a characteristic of apoptosis, and it was observed as concentration-dependent. Thus, this paper clearly demonstrates that human breast cancer cell MCF-7 is highly responsive by red sorghum bran anthocyanins result from the induction of apoptosis in MCF-7 cells
Anticoagulant property of sulphated polysaccharides extracted from marine brown algae collected from Mandapam Island, India
The marine brown algae: Sargassum tenerrimum, Sargassum wightii, Turbinaria conoides, Turbinaria ornata and Padina tetrastromatica were collected from Mandapam Island, India. The crude sulphated polysaccharides (SPS) were extracted using hot water and examined for anticoagulation activity. The sugar, sulphate and protein in crude SPS were analyzed. The presence of sulphated polysaccharide was confirmed by agarose gel electrophoresis and further characterized by Fourier transform infrared spectroscopy (FTIR). The FTIR analysis of crude SPS showed characteristic band of polysaccharides at 900, 1740 cm-1 and ester sulphate at 1250 to 1260 cm-1. Moreover, the absorbance band at 820 cm-1 for S. tenerrimum, S. wightii, T. conoides and T. ornata denotes sulphation at equatorial position, but in the case of P. tetrastromatica, sulphation at axial position is denoted by absorbance band at 850 cm-1. The heparin like activity of crude SPS was determined by metachromatic assay. The anticoagulant activity of crude SPS was evaluated by activated partial thromboplastin time (APTT) and prothrombin time (PT) assays. The metachromatic, APTT and heparinoid activities of crude SPS from S. tenerrimum, S. wightii, T. conoides, T. ornata and P. tetrastromatica were in the range of 0.045 to 0.0347, 134 to 89 s and 25.47 to 14.5 USP units/mg, respectively. The prolongation of prothrombin time by crude SPS was not found.Keywords: Brown algae, sulphated polysaccharides, Fourier transform infrared spectrometer (FTIR), agarose gel, metachromatic activity, activated partial thromboplastin time (APTT), heparinAfrican Journal of Biotechnology Vol. 12(16), pp. 1937-194
Design and Analysis of Fast and Zero Voltage Switching Of Interleaved Flyback Converter with H6 Type Inverter for Photovoltaic Applications
A design and load analysis of interleaved flyback converter with H6 inverter topology is proposed. Flyback converter is one among the DC-DC converter with high frequency which is used or low power applications. Because of high frequency operation switching losses and stresses are more. To reduce stresses and losses across the switch of interleaved flyback converter is proposed. In the grid tied inverter system leakage current is one of the disadvantages and to avoid this H6 type inverter is used. With this advantage of H6 inverter and flyback converter this paper is mainly focused on stresses across switches and eliminating leakage current, harmonic reduction. Further the fast switching is proposed within converter in order to deliver maximum power transfer delivered to load through grid. To validate the overall performance the proposed converter modeled in MATLAB-SIMULINK and prototype developed using DSP DSP TMS320F28377S and connected to grid connected load
Immune associated LncRNAs identify novel prognostic subtypes of renal clear cell carcinoma
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/148402/1/mc22949_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148402/2/mc22949.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148402/3/mc22949-sup-0001-SuppData-S1.pd
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