964 research outputs found
Development of an integrated model for process planning and parameter selection for machining processes
The concept of Do it right the first time in the machining industry not only expects the best quality products but also at the best possible cost. The cost of machining depends on intelligent process planning and selection of machining parameters such as speed, feed, and depth of cut. The problem of machining parameter selection has received great attention by researchers and many techniques have been developed. A review of these techniques reveals that the selection of the machine and cutting tool is done before the process of cutting parameter selection and process sequencing, and often the selection is based on experience. The current research is an attempt to develop an integrated model (ExIMPro: EXpert system based Integrated model for Machining PROcesses) which finds the sequence of operations with set of machines, tools, and other process parameters to minimize the cost of machining for a cylindrical part. This system consists of existing expert system Machining Parameter SELection (MPSEL) for machine and tool selection and a Microsoft ExcelRTM and Visual BasicRTM based parameter selection model. The present model focuses on turning and cylindrical grinding operations but other processes can be incorporated with little modification to the software
Energy-sensitive machining parameter optimization model
Manufacturing industries are one of the most important elements in the economic growth and stability of any country. It is very important that the process parameters are given proper attention to maximize the value addition and increased profits for these industries. Parameter optimization for different manufacturing processes has been a challenging and interesting problem in the past. Many researchers have studied the problem of optimizing the process parameters for the turning process. In all the cases studied so far, no one has considered the significance of energy required and its cost for the machining process as an integral part of the optimization process. With the recent problems in the supply of energy and the increasing energy demand and cost, consideration of issues and problems related to energy usage has become a priority for the manufacturing industry.;The proposed research aims to bridge the gap between the concept of machining economics and the energy conservation. A single pass turning operation was considered, to demonstrate the optimization of process parameters so that the overall cost of manufacturing is minimized. A geometric programming mathematical model was developed to address the concept of energy sensitive parameter optimization process. The proposed model adds a new dimension to the existing literature on machining economics problems since the energy cost has never been considered in the optimization process. A solution methodology had been developed to find the optimal or near optimal process parameters. Last but not the least; this research is focused on today\u27s need of the world, the energy efficiency awareness
Whimsical Nature of Tughlaq
The present research paper deals with Whimsical nature of Tughlaq. Tughlaq is protagonist of Girish Karnad’s famous play Tughlaq. He was the sultan of Delhi in 14th century. The play was written by Girish Karnad in 1964. Tughlaq by Girish Karnad is a classic in Indian English drama. It tells the story of Muhammad Bin Tughlaq, exploring the rationale behind his actions and exploring his psyche. The action of the play takes place in 14th century and it gives a clear picture of that time and character of Tughlaq. In the play Tughlaq is Impulsive and Whimsical king. He always thinks that he is right and all his actions are right too. Nobody can foretell his moods and actions in his own fate. As a king Tughlaq took many decisions but all the plan of Tughlaq has failed due to his negligence and becomes problem for Delhi residents. Thus for his mad plans he was regarded as a mad king
Biodegradable microparticulate drug delivery system of diltiazem HCl
The efficacy of a drug in a specific application requires the maintenance of appropriate drug blood level concentration during a prolonged period of time. Controlled release delivery is available for many routes of administration and offers many advantages (as microparticles and nanoparticles) over immediate release delivery. These advantages include reduced dosing frequency, better therapeutic control, fewer side effects, and, consequently, these dosage forms are well accepted by patients. Advances in polymer material science, particle engineering design, manufacture, and nanotechnology have led the way to the introduction of several marketed controlled release products and several more are in pre-clinical and clinical development. The objective of this work is to prepare and evaluate diltiazem HCl loaded albumin microparticles using a factorial design. Albumin (natural polymer) microparticles were prepared by emulsion heat-stabilization method. Selected formulations were characterized for their entrapment efficiency, particle size, surface morphology, and release behavior. Analysis of variance for entrapment efficiency indicates that entrapment efficiency is best fitted to a response surface linear model. Surface morphology was studied by scanning electron microscopy. Scanning electron microscopy of the microparticles revealed a spherical, nonporous and uniform appearance, with a smooth surface. The geometric mean diameter of the microparticles was found to be 2-9 µm, which more than 75% were below 3.5 µm and drug incorporation efficiency of 59.74 to 72.48% (w/w). In vitro release profile for formulations containing diltiazem HCl loaded BSA microparticles with heat stabilization technique shows slow controlled the release of the drug up to 24 hours. The release pattern was biphasic, characterized by an initial burst effect followed by a slow release. All selected microparticles exhibited a prolonged release for almost 24 hours. On comparing regression-coefficient (r²) values for Hixson Crowel, Higuchi and Peppas kinetic models, different batches of microparticles showed Fickian, non-Fickian, and diffusion kinetics. The release mechanism was regulated by D:P ratio. From the statistical analysis it was observed that as the drug:polymer (D:P) ratio increased, there was a significant increase in the encapsulation efficiency. Based on the particle size, entrapment efficiency and physical appearance, DTM-3 formulations were selected for in vivo release study and stability study. The in vivo result of drug loaded microparticles showed preferential drug targeting to liver followed by lungs, kidneys and spleen. Stability studies showed that maximum drug content and closest in vitro release to initial data were found in the formulation stored at 4 ºC. In present study, diltiazem HCl loaded BSA microparticles were prepared and targeted to various organs to satisfactory level and were found to be stable at 4 ºC.A eficácia terapêutica de um fármaco depende da manutenção de seu nível plasmático adequado em determinado intervalo de tempo. Nesse sentido, a liberação modificada de fármacos está disponível em muitas vias de administração e oferece muitas vantagens (como micropartículas e nanopartículas) quando comparada às formulações de liberação imediata. Essas vantagens incluem reduzida frequência da dosagem, melhor controle terapêutico e menos efeitos colaterais. Assim sendo, esses produtos apresentam maior aceitação pelos pacientes. Os avanços na ciência dos materiais, na engenharia das partículas, em manufatura e em nanotecnologia permitiram a introdução no mercado de vários produtos de liberação modificada e vários outros se encontram em desenvolvimento pré-clínico e clínico. O objetivo do presente trabalho foi preparar e avaliar o fármaco cloridrato de diltiazem associado a micropartículas de albumina utilizando planejamento fatorial. As micropartículas de albumina, um polímero natural, foram preparadas por método de emulsão empregando estabilização por calor. As formulações selecionadas foram caracterizadas no que se refere à sua eficiência de encapsulamento, tamanho médio de partículas, morfologia de superfície e perfil de liberação do fármaco. A análise de variância relativa à eficiência de encapsulamento indicou superfície de resposta linear. Com referência à morfologia superficial, essa foi avaliada empregando microscopia eletrônica de varredura. Essa análise revelou micropartículas esféricas, não porosas e de aparência uniforme, com superfície lisa. O diâmetro médio das micropartículas foi entre 2 e 9 µm, sendo que mais de 75% das micropartículas se apresentaram abaixo de 3,5 µm. Além disso, a eficiência de encapsulamento foi entre 59,74 e 72,48%. Quanto ao ensaio para avaliação do perfil de liberação in vitro do fármaco associado às micropartículas, as formulações apresentaram liberação lenta até 24 horas. O comportamento foi caracterizado por liberação inicial (efeito burst) seguida por liberação lenta. Todas as fórmulas selecionadas apresentaram liberação prolongada por aproximadamente 24 horas. Na comparação entre os valores de coeficientes de regressão (R²), os modelos propostos por Hixson Crowel, Higuchi e Peppas, para diferentes formulações de micropartículas, demonstraram cinética de liberação de acordo com modelo Fickiano e não-Fickiano. O mecanismo de liberação do fármaco foi regulado pela razão entre o fármaco e o polímero. A análise estatística revelou significativo aumento da eficiência de encapsulamento quando essa razão aumentou. As avaliações relativas à análise dimensional das micropartículas, à eficiência de encapsulamento do fármaco e à morfologia permitiram a seleção da formulação DTM-3 para os ensaios de liberação in vivo e para o estudo da estabilidade. O ensaio de liberação in vivo do fármaco associado às micropartículas demonstrou sítio-alvo preferencial no fígado, seguido pelos pulmões rins e baço. No presente estudo, as micropartículas de albumina contendo cloridrato de diltiazem foram adequadamente preparadas e orientadas satisfatoriamente para vários órgãos. Além disso, a formulação selecionada apresentou estabilidade físico-química a 4 ºC
Biodegradable microparticulate drug delivery system of diltiazem HCl
A eficácia terapêutica de um fármaco depende da manutenção de seu nível plasmático adequado em determinado intervalo de tempo. Nesse sentido, a liberação modificada de fármacos está disponível em muitas vias de administração e oferece muitas vantagens (como micropartículas e nanopartículas) quando comparada às formulações de liberação imediata. Essas vantagens incluem reduzida frequência da dosagem, melhor controle terapêutico e menos efeitos colaterais. Assim sendo, esses produtos apresentam maior aceitação pelos pacientes. Os avanços na ciência dos materiais, na engenharia das partículas, em manufatura e em nanotecnologia permitiram a introdução no mercado de vários produtos de liberação modificada e vários outros se encontram em desenvolvimento pré-clínico e clínico. O objetivo do presente trabalho foi preparar e avaliar o fármaco cloridrato de diltiazem associado a micropartículas de albumina utilizando planejamento fatorial. As micropartículas de albumina, um polímero natural, foram preparadas por método de emulsão empregando estabilização por calor. As formulações selecionadas foram caracterizadas no que se refere à sua eficiência de encapsulamento, tamanho médio de partículas, morfologia de superfície e perfil de liberação do fármaco. A análise de variância relativa à eficiência de encapsulamento indicou superfície de resposta linear. Com referência à morfologia superficial, essa foi avaliada empregando microscopia eletrônica de varredura. Essa análise revelou micropartículas esféricas, não porosas e de aparência uniforme, com superfície lisa. O diâmetro médio das micropartículas foi entre 2 e 9 µm, sendo que mais de 75% das micropartículas se apresentaram abaixo de 3,5 µm. Além disso, a eficiência de encapsulamento foi entre 59,74 e 72,48%. Quanto ao ensaio para avaliação do perfil de liberação in vitro do fármaco associado às micropartículas, as formulações apresentaram liberação lenta até 24 horas. O comportamento foi caracterizado por liberação inicial (efeito burst) seguida por liberação lenta. Todas as fórmulas selecionadas apresentaram liberação prolongada por aproximadamente 24 horas. Na comparação entre os valores de coeficientes de regressão (R²), os modelos propostos por Hixson Crowel, Higuchi e Peppas, para diferentes formulações de micropartículas, demonstraram cinética de liberação de acordo com modelo Fickiano e não-Fickiano. O mecanismo de liberação do fármaco foi regulado pela razão entre o fármaco e o polímero. A análise estatística revelou significativo aumento da eficiência de encapsulamento quando essa razão aumentou. As avaliações relativas à análise dimensional das micropartículas, à eficiência de encapsulamento do fármaco e à morfologia permitiram a seleção da formulação DTM-3 para os ensaios de liberação in vivo e para o estudo da estabilidade. O ensaio de liberação in vivo do fármaco associado às micropartículas demonstrou sítio-alvo preferencial no fígado, seguido pelos pulmões rins e baço. No presente estudo, as micropartículas de albumina contendo cloridrato de diltiazem foram adequadamente preparadas e orientadas satisfatoriamente para vários órgãos. Além disso, a formulação selecionada apresentou estabilidade físico-química a 4 ºC.The efficacy of a drug in a specific application requires the maintenance of appropriate drug blood level concentration during a prolonged period of time. Controlled release delivery is available for many routes of administration and offers many advantages (as microparticles and nanoparticles) over immediate release delivery. These advantages include reduced dosing frequency, better therapeutic control, fewer side effects, and, consequently, these dosage forms are well accepted by patients. Advances in polymer material science, particle engineering design, manufacture, and nanotechnology have led the way to the introduction of several marketed controlled release products and several more are in pre-clinical and clinical development. The objective of this work is to prepare and evaluate diltiazem HCl loaded albumin microparticles using a factorial design. Albumin (natural polymer) microparticles were prepared by emulsion heat-stabilization method. Selected formulations were characterized for their entrapment efficiency, particle size, surface morphology, and release behavior. Analysis of variance for entrapment efficiency indicates that entrapment efficiency is best fitted to a response surface linear model. Surface morphology was studied by scanning electron microscopy. Scanning electron microscopy of the microparticles revealed a spherical, nonporous and uniform appearance, with a smooth surface. The geometric mean diameter of the microparticles was found to be 2-9 µm, which more than 75% were below 3.5 µm and drug incorporation efficiency of 59.74 to 72.48% (w/w). In vitro release profile for formulations containing diltiazem HCl loaded BSA microparticles with heat stabilization technique shows slow controlled the release of the drug up to 24 hours. The release pattern was biphasic, characterized by an initial burst effect followed by a slow release. All selected microparticles exhibited a prolonged release for almost 24 hours. On comparing regression-coefficient (r²) values for Hixson Crowel, Higuchi and Peppas kinetic models, different batches of microparticles showed Fickian, non-Fickian, and diffusion kinetics. The release mechanism was regulated by D:P ratio. From the statistical analysis it was observed that as the drug:polymer (D:P) ratio increased, there was a significant increase in the encapsulation efficiency. Based on the particle size, entrapment efficiency and physical appearance, DTM-3 formulations were selected for in vivo release study and stability study. The in vivo result of drug loaded microparticles showed preferential drug targeting to liver followed by lungs, kidneys and spleen. Stability studies showed that maximum drug content and closest in vitro release to initial data were found in the formulation stored at 4 ºC. In present study, diltiazem HCl loaded BSA microparticles were prepared and targeted to various organs to satisfactory level and were found to be stable at 4 ºC
Spitzer Space Telescope observations of hot Jupiters
Currently the Spitzer Space Telescope is the most reliable telescope for conducting secondary eclipse observations of exoplanets. The depth and the time of mid-eclipse are two important parameters that come from a secondary eclipse analysis. The eclipse depth gives information on the temperature of the atmosphere, and can provide evidence for the presence of molecules in the atmosphere of the planet. If multiple wavelengths have secondary eclipse depths measured then it is possible to constrain the spectral energy distribution (SED) of the atmosphere given some assumptions on, for example, the metallicity of the planet's atmosphere. The time of mid-eclipse gives e cos which, with an analysis including transit, radial velocity and secondary eclipse data, can strongly constrain the eccentricity of the planet's orbit. To fully understand the conclusions drawn from these two parameters realistic error bars must be quoted
on the measurement of these parameters. It is generally understood that error bars that come from MCMC analyses of secondary eclipse observations are underestimated
because the correlated noise in the data is not accounted for in the analysis. The goal of this thesis was to find a method to improve the estimates of the uncertainties on these two parameters as derived from Spitzer secondary eclipse lightcurves at 3.6 um and 4.5 um. This work was conducted through the generation and fitting of semi-synthetic Spitzer secondary eclipse light curves. I estimate the amount the uncertainties on these parameters need to be inflated by and show how my results compare with other similar work in the field. I show that the amount of inflation does affect the conclusions drawn
when fitting these data with model atmospheres. This could also mean that for systems where complex chemistry is invoked to explain the observed data, simpler model can now fit the data due to the increase in the error bars. I also find that when multiple realisations of the same, simulated, secondary eclipse lightcurve are fit with the standard MCMC code, the amplitude and time of mid-eclipse can be recovered and found to be more than 3 away from the true value of the injected signal. This can mean that, because usually only 1 lightcurve is obtained per observation of the secondary eclipse, some detections of eccentricity and molecules may not be real detections but simply a result of noise in the data
The Effect of Coduse Group Exercise Improves Balance and Reduce Falls in Patients with Multiple Sclerosis: A Comparative study
BACKGROUND:
Imbalance leading to falls is common in people with multiple sclerosis (PwMS).
OBJECTIVE:
To evaluate the effects of a balance group exercise programme (CoDuSe) on balance and walking in PwMS (Expanded Disability Status Scale, 4.0–7.5).
METHODS:
A multi-centre, randomized, controlled single-blinded pilot study with random allocation to early or late start of exercise, with the latter group serving as control group for
the physical function measures. In total, 14 supervised 60-minute exercise sessions were delivered over 7 weeks. Pretest–posttest analyses were conducted for self-reported near falls and falls in the group starting late. Primary outcome was Berg Balance Scale (BBS). A total of 51 participants were initially enrolled; three were lost to follow-up.
RESULTS:
Post-intervention, the exercise group showed statistically significant improvement (p = 0.015) in BBS and borderline significant improvement in MS Walking Scale (p = 0.051),
both with large effect sizes (3.66; −2.89). No other significant differences were found between groups. In the group starting late, numbers of falls and near falls were statistically significantly reduced after exercise compared to before (p < 0.001 ; p < 0.004).
CONCLUSION:\ud
This pilot study suggests that the CoDuSe exercise improved balance and reduced perceived walking limitations, compared to no exercise. The intervention reduced falls and near falls frequency
Glycemic control in smokers and risk of type 2 diabetes
Chronic cigarette smoking seems to markedly aggravate insulin resistance that could be due to the increase in counter-regulatory hormones such as GH, cortisol and catecholamine's that elevates blood glucose, Weight gain usually follows the cessation of smoking and increasingly, fear of weight gain discourages many smokers from attempting to quit Yet, weight gain after quitting smoking has proved so unresponsive  to preventive attempt  as to suggest that weight control  might even be incompatible with successful smoking cessation . Innovative treatments that can prevent or minimize weight gain are badly needed to encourage quitting smoking. However recently featured review and research on smoking and diabetes concluded the evidence that smoking is associated with the preparation for development of type 2 diabetes in men and women Therefore, this review focuses in the possible features of smoking cessation on the glycemic control and risk of type 2 diabetes.key words: Hyperglycemia,Smokers, types 2 diabete
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