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New Method for Synthesis of Coatings of Molybdenum, Tungsten, Their Carbides and Composites  [PDF]
Rhushikesh V. Godbole, Mahendra A. More, Anil S. Gupte, Vijay P. Godbole
Open Journal of Synthesis Theory and Applications (OJSTA) , 2013, DOI: 10.4236/ojsta.2013.22010
Abstract:

In this paper we report, for the first time, a new approach for synthesis of high quality faceted microcrystalline coatings of molybdenum (Mo), tungsten (W), their carbides and composites. These studies are carried out using Hot Filament Chemical Vapor Deposition (HF-CVD) method wherein parent materials (Mo and/or W) are taken in the form of wires (~0.5 mmdia) and are heated to a high temperature (TF ~ 1500 - 2000 C), in ambient of oxygen (O2) diluted hydrogen (H2) gas. Due to high filament temperature (TF), a series of pyrolytic reactions take place. Firstly, the gasification of wire material (Mo and/or W) occurs in the form of its oxide. The oxide molecules reach the substrate which is kept underneath the filament assembly. Secondly, molecular hydrogen gets dissociated into atomic hydrogen and subsequently reaches the substrate to react with oxide molecules, finally leading to the precipitation of a pure metal. This method can also be used, in situ, to convert metallic coatings into their carbides and/or composites. The method offers many other attractive features, which can not be rendered by the conventionalCVD/PVDmethods. The results are discussed in terms of temperature induced “Red-ox” reactions.

Microwave Plasma Enhanced Chemical Vapor Deposition of Carbon Nanotubes  [PDF]
Ivaylo Hinkov, Samir Farhat, Cristian P. Lungu, Alix Gicquel, Fran?ois Silva, Amine Mesbahi, Ovidiu Brinza, Cornel Porosnicu, Alexandru Anghel
Journal of Surface Engineered Materials and Advanced Technology (JSEMAT) , 2014, DOI: 10.4236/jsemat.2014.44023
Abstract:

Multi-walled carbon nanotubes (MWCNTs) were grown by plasma-enhanced chemical vapor deposition (PECVD) in a bell jar reactor. A mixture of methane and hydrogen (CH4/H2) was decomposed over Ni catalyst previously deposited on Si-wafer by thermionic vacuum arc (TVA) technology. The growth parameters were optimized to obtain dense arrays of nanotubes and were found to be: hydrogen flow rate of 90 sccm; methane flow rate of 10 sccm; oxygen flow rate of 1 sccm; substrate temperature of 1123 K; total pressure of 10 mbar and microwave power of 342 Watt. Results are summarized and significant main factors and their interactions were identified. In addition a computational study of nanotubes growth rate was conducted using a gas phase reaction mechanism and surface nanotube formation model. Simulations were performed to determine the gas phase fields for temperature and species concentration as well as the surface-species coverage and carbon nanotubes growth rate. A kinetic mechanism which consists of 13 gas species, 43 gas reactions and 17 surface reactions has been used in the commercial computational fluid dynamics (CFD) software ANSYS Fluent. A comparison of simulated and experimental growth rate is presented in this paper. Simulation results agreed favorably with experimental data.

Prevalence of daily or near daily aspirin use by US adults with diabetes: A cross-sectional study using a multi-year national database  [PDF]
Michael F. Akers, M. Nawal Lutfiyya, Maria L. Amaro, Michael T. Swanoski
Health (Health) , 2012, DOI: 10.4236/health.2012.46049
Abstract: Introduction: For persons with diabetes, cardiovascular disease is the major cause of morbidity and mortality that is reflected in a two-to- four times greater risk for both heart disease and stroke when compared to adults without diabetes. Although not without controversy, diabetes and cardiovascular disease (CVD) management guidelines in the US recommend the use of once-daily aspirin. This epidemiological study was undertaken to fill the knowledge gap regarding the prevalence of daily or near daily aspirin use for US age-appropriate adults with diabetes. Methods: Using bivariate and multivariate techniques, a cross-sectional analysis of an amalgamated database using 2005, 2007, and 2009 Behavioral Risk Factor Surveillance Survey data was performed. The dependent variable for this analysis was daily or near daily aspirin use. The population of interest was US adults, men >= 45 - 79 and women >= 55 - 79 years of age. Results: Overall the prevalence of daily or near daily aspirin use by age-appropriate US adults with diabetes was 62.5%; it was 41.0% for similar non-diabetic adults. Logistic regression analysis yielded that age-appropriate adults, of both genders, with diabetes taking daily or near daily aspirin were more likely to be: physically active, male, live in rural locales, not have a health care provider, have deferred medical care because of cost, have an elevated BMI, a smoker, and have hypertension. Conclusion: It was determined that the age-appropriate use of aspirin in the US adult population with diabetes is underutilized. The role of the pharmacist through- out the continuum of care is one way to improve appropriate aspirin use in patients with diabetes.
The Pharmacogenomic Consideration of Lipid Homeostasis: Role of Pharmacist in Ethical and Economic Consideration  [PDF]
Paul Serafin, Mohammad Newaz
Pharmacology & Pharmacy (PP) , 2013, DOI: 10.4236/pp.2013.41017
Abstract: Usage of lipid lowering drugs is a common therapeutic steps in preventing or treating diseases. With the advent of Pharmacogenetics and Pharmacogenomics, it is now important to understand the implication of pharmacogenetic testing in patient care. Ethical and economic concerns are wide considered to be an issue in a pharmacy setting and it is important that the health care professionals in the pharmacy setting need to be aware. This article encompasses current pharmacogenomic information that is relevant to lipid homeostasis and addressed the concerns of patient that may be a factor in ultimate decision making process.
Combined Therapy of Pioglitazone and Atorvastatin Alleviate Diabetes in Rats More Effectively than That of Mono Therapy  [PDF]
Hazrat Ali, A. F. M. Towheedur Rahman, Saiful Islam, Al Mamun, Shaheda Zannah, A. H. M. Khurshid Alam, Aziz Abdur Rahman, Mamunur Rashid
Pharmacology & Pharmacy (PP) , 2014, DOI: 10.4236/pp.2014.55060
Abstract:

Present research was designated to investigate the hypoglycemic, hypolipidemic and antioxidant activity of the combination of pioglitazone and atorvastatin on long-term alloxan-induced diabetes rats (AIDRs). The experiments were carried out to determine blood glucose level, lipid profile, free radial scavenging activities, superoxide dismutase (SOD) and catalase in liver tissue. In addition, left ventricular (LV) hypertrophy and cardiomyocyte size were also determined by histological analysis. It was found that in short-term induction, pioglitazone significantly reduced the blood glucose level without having any considerable effect on lipid profile and antioxidant enzymes (SOD and catalase) in rats. On the other hand, atorvastatin significantly reduced total cholesterol (TC), triglyceride (TG) and low density lipoprotein cholesterol (LDL-C) with marked increase in the level of high density lipoprotein cholesterol (HDL-C) and improved activity of SOD and catalase enzymes. However, pathological changes of heart and pancreas were not observed after short-term exposure to alloxan in rats. Long-term diabetes induction resulted in LV hypertrophy and prominent shrinkage of islets of Langerhans cells. Treatment with atorvastatin in combination with pioglitazone significantly reduced the LV hypertrophy, TC, TG and LDL level whereas they noticeably increased HDL level, DPPH (1,1-Diphenyl-2-picryl-hydrazyl) free radical scavenging activity, SOD and catalase activity with satisfactory recovery of Langerhans cells. The result demonstrated that combination therapy was more effective than that of mono-therapy for preventing diabetes with cardiovascular diseases (CVD) in rats.

Nitrogen Desorption and Positron Sensitive Defect of CVD Diamond  [PDF]
Kasey R. Lund, Kelvin G. Lynn, Marc H. Weber, Chao Liu, Elgin Eissler
Journal of Modern Physics (JMP) , 2017, DOI: 10.4236/jmp.2017.85049
Abstract: The chemical vapor deposition (CVD) process can produce single or poly-crystalline diamond samples of high purity or with controlled doping concentrations. The defect type in the CVD diamonds can be changed by heating the samples. Controlling the defect type can be used to create devices for quantum diamond switches that could be used in radiation sensors and quantum information technology. Eight samples of CVD diamonds were analyzed with Doppler broadening of positron annihilation radiation (DBAR) before and after annealing in high vacuum with an electron gun. Between temperatures of 1700 - 1850 K, nitrogen was liberated from the diamond sample. At these high temperatures, the surface was graphitized and a change in the color and transparency of the diamond was observed. Some of the samples were analyzed with DBAR during periods with and without light. The defect properties were observed to change depending on the time exposure to the positron beam and were then regenerated by exposure to light. The DBAR data is compared to photoluminescence data and a time varying defect state is discussed for detector and optical grade type II CVD diamonds.
Synthesis and Fabrication of Graphene and Graphene Oxide: A Review  [PDF]
Adeniji Adetayo, Damilola Runsewe
Open Journal of Composite Materials (OJCM) , 2019, DOI: 10.4236/ojcm.2019.92012
Abstract: The field of nanotechnology has advanced following the discovery of a two-dimensional material of sp2 hybridized carbon atoms, graphene in 2004 by Geim and Novoselov. Graphene has received so much attention due to its exceptional electronic, thermal, mechanical, and optical properties in addition to its large surface area and single-atom thickness. This has led to the discovery of several techniques to obtain graphene such as chemical exfoliation, chemical vapor deposition (CVD), chemical synthesis etc. However, these techniques are majorly challenged with developing graphene with fewer defects and in large scale; thus, there is an increasing need to produce graphene in large quantities with high quality. Several studies have been carried out to find routes to producing high-quality graphene. This paper focuses majorly on the synthesis and fabrication methods of producing graphene and its derivative, graphene oxide. Characterization techniques to identify graphene such as optical microscopy, scanning electron microscopy (SEM), Raman spectroscopy, scanning probe microscopy (SPM) used to determine number of layers, quality, atomic structures, and defects in graphene is also briefly discussed. This article also covers a short description of graphene applications in transparent electrodes, composites and energy storage devices.
State level correlations between high heart attack and stroke symptomology knowledge scores and CVD risk factors and mortality rates  [PDF]
Mary Nawal Lutfiyya, Krista L. Huot, Maria L. Amaro, Michael F. Akers, Michael Swanoski
Health (Health) , 2013, DOI: 10.4236/health.2013.510220
Abstract:

Introduction: In 2008, cardiovascular disease (CVD) accounted for one in three deaths in the United States. Epidemiological analyses suggest that two or more risk factors are the indicator of high risk and/or poor CVD outcomes. Knowledge of heart attack and stroke symptomology has been the focus of much research based on the assumption that accurate identification of an event is critical to reducing time to treatment. There is a paucity of research showing a clear association between knowledge of heart attack and stroke symptomology, risk factors, and mortality rates. In this study, we hypothesized that high stroke and heart attack symptomology knowledge scores would correspond to lower stroke or CVD mortality rankings as well as to a lower prevalence of two or more CVD risk factors. Methods: State was the unit of analysis used to examine data from two different sources and combined into a customized database. The first source was a multiyear Behavioral Risk Factor Surveillance Survey (BRFSS) heart attack and stroke symptom knowledge module database. CVD and stroke mortality data used came from the American Heart Association’s (AHA) 2012 Heart Disease and Stroke Statistics Update. Spearman’s Rho was the test statistic. Results: A moderate negative correlation was found between high heart attack and stroke symptom knowledge scores and the percentage of adults with two or more CVD or stroke risk factors. Likewise, a similar correlation resulted from the two variables, high heart attack and stroke symptoms knowledge score and CVD mortality rank. Conclusions: This study demonstrated a significant relationship between high heart attack and stroke symptom knowledge and lower CVD mortality rates and lower prevalence of two or more CVD risk factors at the state level. Our findings suggest that it is important to continue education efforts regarding heart attack and stroke symptom knowledge. Pharmacists are one group of health care providers who could enhance the needed public health education efforts.

Sistema RTP: uma técnica poderosa para o monitoramento da forma??o de nanotubos de carbono durante o processo por deposi??o de vapor químico
Trist?o, Juliana Cristina;Moura, Flávia Cristina Camilo;Lago, Rochel Montero;Sapag, Karim;
Química Nova , 2010, DOI: 10.1590/S0100-40422010000600028
Abstract: in this work, a tpr (temperature programmed reduction) system is used as a powerful tool to monitor carbon nanotubes production during cvd (chemical vapour deposition), the experiments were carried out using catalyst precursors based on fe-mo supported on al2o3 and methane as carbon source. as methane reacts on the fe metal surface, carbon is deposited and h2 is produced. tpr is very sensitive to the presence of h2 and affords information on the temperature where catalyst is active to form different forms of carbon, the reaction kinetics, the catalyst deactivation and carbon yields.
The role of aspirin in women’s health
Verheugt FWA, Bolte AC
International Journal of Women's Health , 2011, DOI: http://dx.doi.org/10.2147/IJWH.S18033
Abstract: ole of aspirin in women’s health Review (6350) Total Article Views Authors: Verheugt FWA, Bolte AC Published Date June 2011 Volume 2011:3 Pages 151 - 166 DOI: http://dx.doi.org/10.2147/IJWH.S18033 Freek WA Verheugt1, Antoinette C Bolte2 1Department of Cardiology, Onze Lieve Vrouwe Gasthuis (OLVG), Amsterdam, The Netherlands; 2VU University Medical Center, Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, Amsterdam, The Netherlands Background: The aim of this review is to discuss the role of aspirin for various conditions in women. Methods: A nonsystematic review of articles published on PubMed that examines the role of aspirin in women. Results: Aspirin is associated with a significant reduction of stroke risk in women, which may be linked to age. However, despite this evidence, underutilization of aspirin in eligible women is reported. In women of reproductive age, it may also have a role to play in reducing early-onset preeclampsia and intrauterine growth restriction, and in the prevention of recurrent miscarriage in women with antiphospholipid antibodies; it may also reduce cardiovascular risk in associated systemic conditions such as lupus. Aspirin may reduce colorectal cancer risk in women, but its role in breast cancer warrants further data from controlled trials. Conclusions: The risk–benefit threshold for aspirin use in women has been established for several conditions. Reasons why women are less likely to be prescribed aspirin have not been established, but the overall underuse of aspirin in women needs to be addressed.
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