Role of garnet and silicon carbide abrasives in abrasive waterjet cutting of aluminum-silicon carbide particulate metal matrix composites

This paper covers studies on machinability of aluminum-silicon carbide particulate metal matrix composites (Al-SiCp MMCs) with abrasive waterjets (AWJs) produced by two different types of abrasives. Four different compositions of Al-SiCp MMCs were processed with 60, 80 and 120 mesh size garnet and SiC abrasives with a view to identify the correct type and size of abrasive for effective processing of MMCs with AWJs. The maximum penetration ability of AWJs in different MMCs was examined by conducting the experiments on a wedge shaped Al-SiCp MMC specimens, prepared with stir casting method. Optical micrographs of MMC samples and scanning electron microscopic (SEM) examination of AWJ cut surfaces enabled to explain the trends of material removal with both types of abrasives. Analysis of results clearly indicated the choice of 80 mesh size SiC abrasives for effective processing of Al-SiCp MMCs with AWJs

Influence of rootstock scion combinations on morpho-physiological traits in Coffee

An experiment was conducted using coffee seedlings to find out the influence of rootstock scion interactions on morpho-physiological traits. Commercially important arabica cultivars such as S.795, Sln.10 and S.4202 were grafted on drought tolerant rootstocks of arabica cultivars such as Sln.9, Sln.5 (B), Sln.11and two high vigour robusta cultivars like S.274 and C x R. Results on morpho-physiological traits indicated significant differences between rootstock scion combinations. The interaction effects in comparison with pure line seedlings of scion materials indicated that, the robusta rootstocks being diploid species (2n=22), significantly reduced the growth of tetraploid (2n=44) arabica scion materials. Results on physiological and morphological traits indicated that the higher vigour in arabica/arabica combinations compared to robusta/arabica and self graft combinations might be due to the influence of genetically divergent rootstocks of same species. Correlation analysis indicated significant positive relationship between specific leaf area and absolute growth rate (r=0.560), net assimilation rate (r=0.498) and relative leaf growth rate (r=0.587) and also leaf area duration with absolute growth rate (r=0.753) indicating role of specific leaf area and leaf area duration in governing growth and development of coffee graft combinations. The Sln.9 and Sln.5B rootstocks for S.4202 scion, Sln.5B and Sln.11 for Sln.10 scion and Sln.9 and Sln.5B rootstocks for S.795 scion were found to be efficient and could be field evaluated for yielding performance

Awareness and practices on eye effects among people with diabetes in rural Tamil Nadu, India

Background: Recently eye effects of Diabetes Mellitus (DM) are an important concern due to increase in its trend especially in developing countries.Objectives: To assess the awareness related to eye effects of DM and its prevention practices among people with diabetes.Methods: This cross sectional study was conducted from January 2013 to April 2013 in Villupuram district of Tamil Nadu, India. All 105 people with diabetes from the service area of two sub-centres were included. Data on socio demographic details, history of DM, awareness on systemic complications of DM, effects of DM on eyes, practice on regular blood check-up, eye examination and source of information were collected by interview technique using a structured questionnaire. Univariate and multiple logistic regression analysis were done to assess the association of awareness of eye examination with socio-demographic variables.Results: Mean age of the study population was 56.7 years. About 93 people with diabetes (88.6%) tested their blood sugar at least once in every 3 months. About 80 people with diabetes (76.2%) were aware of at least one systemic complication of DM. Although 78 (74.3%) people with diabetes were aware that DM could affect the eyes, majority of this group (68, 87.2%) did not know the specific effects of DM on eyes. In this group, about 28(35.9%) people with diabetes were not aware of the reasons for eye effects, while others mentioned that persistent high blood sugar level (n=26, 33.3%), longer duration of DM (n=14, 17.9%) and lifestyle (n=10, 12.8%) were the reasons for the eye effects of DM. Only 31 (29.5%) of them knew that their eyes must be regularly examined. People with diabetes who had post-secondary and above (>10th standard) level of education had significantly higher awareness on examination of eye (Adjusted OR=19.63).Conclusion: Although awareness of people with diabetes on systemic effects of DM was more, their awareness on specific eye effects and need for regular screening was low. Systematic efforts are required to increase awareness on eye effects and importance of regular screening in this population.Keywords: Awareness, diabetes, eye effects, India, practic

Control of Time Scale Dynamical Systems with an Application to Concurrency Control for Real-time Database Systems

Main objective in this paper is to unify results on controllability and observability on time scales and deduce the results of classical theory as a particular case and then resolve the time constraints on concurrency control by incorporating jump operators on time scale dynamical systems.Обобщены результаты исследований управляемости и наблюдаемости при масштабировании во времени. Получены результаты классической теории как частного случая, при этом устранены ограничения по времени при параллельном управлении операторами перехода для динамических масштабируемых систем.Узагальнено результати досліджень керованості та спостережуваності при масштабуванні за часом. Отримано результати класичної теорії як окремого випадку, при цьому усунуто обмеження за часом при паралельному керуванні операторами переходу для динамічних систем, що масштабуються