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With the progression in technologies, conventional cutting of metal with flood cooling is superseded by some other means, viz. minimum quantity lubrication (MQL). Here, in this current work, we present that hexagonal boron nitride (hBN) nano-fluid particles are used in terms of percentage mixed in SAFCO lubricant oil. The factors, viz. cutting velocity, depth and percentage of nanoparticles are varied to obtain the mathematical models and optimisation of responses, viz. temperature and surface roughness. Desirability function analysis (DFA) approach is adopted for the optimisation process, and regression analysis is executed for the mathematical modelling. Also, criteria importance through inter criteria (CRITIC) approach was implemented to evaluate the weightage of responses first before the DFA application. The analysis of variance reveals that all the factors taken into the existent are significantly affecting the outcomes, and nanoparticles percentage being the most one. The percentage increase of nanoparticles in oil leads to better surface conditions, as depicted by the result. The ideal settings for the optimisation of responses undertaken may be expressed as follows: 600 rpm cutting speed, 0.1 mm of depth and 2% nanoparticle percentage in MQL. The mathematical modelling confirms that first-order linear models are sufficient for both the responses under the given set of design of experiments. [ABSTRACT FROM AUTHOR]

Background: Type II Diabetes Mellitus (Type II DM) is a metabolic disorder characterized by glucotoxicity and lipotoxicity. Markers of glycemic control are HbA1c, fasting blood glucose and postprandial blood glucose. There is altered lipid parameters in Type II DM which possess significant cardiovascular risk to the patient. Recent studies have shown that ceruloplasmin, an inflammatory marker having antioxidant property,is ideal marker to know the cardiovascular status, degree of insulin resistance and cancer risk. Aims and Objectives: Present study was carried out to determine the relation between glycemic status and serum ceruloplasmin along with lipid parameters which reflects the cardiovascular status in these patients. Materials and Methods: Blood samples were collected from eighty-eight patients with type II diabetes mellitus along with age and sex matched forty-two healthy controls. Fasting lipid profile and blood glucose, postprandial blood glucose, serum ceruloplasmin and HbA1c levels were determined using auto analyser in the department of clinical biochemistry in Institute of Medicine.Appropriate tests of significance were computed by SPSS version 20. Results: Serum ceruloplasmin was found higher in type II DM than nondiabetic group, median 52.0 (95% CI: 49-53) mg/dl versus median 45.0 (95% CI: 41-47) mg/dl, at significant level of 0.001 probability test. Similarly, fasting blood glucose, post prandial glucose, HbA1c and TG/HDL cholesterol ratio correlated significantly with serum ceruloplasmin.The cut off value of 46.5 mg/dL was obtained for serum ceruloplasmin with sensitivity of 87.5% and specificity of 62% which has good discriminating value for type II diabetic patients versus non-diabetic patients. Conclusion: Findings in our study shows that increased glycation coupled with altered lipid profile in type II DM causes enhanced generation of ceruloplasmin which could be used as potential marker for identifying acceleratedglycation and atherogenesis in these subjects. [ABSTRACT FROM AUTHOR]

Background: The hypothesis that circadian clocks confer adaptive advantage to organisms has been proposed based on its ubiquity across almost all levels of complexity and organization of life-forms. This thought has received considerable attention, and studies employing diverse strategies have attempted to investigate it. However, only a handful of them have examined how selection for circadian clock controlled rhythmic behaviors influences lifehistory traits which are known to influence Darwinian fitness. The 'early' and 'late' chronotypes are amongst the most widely studied circadian phenotypes; however, life-history traits associated with these chronotypes, and their consequences on Darwinian fitness remain largely unexplored, primarily due to the lack of a suitable model system. Here we studied several life-history traits of Drosophila melanogaster populations that were subjected to laboratory selection for morning (early) and evening (late) emergence. Results: We report that the late eclosion chronotypes evolved longer pre-adult duration as compared to the early eclosion chronotypes both under light/dark (LD) and constant dark (DD) conditions, and these differences appear to be mediated by both clock dependent and independent mechanisms. Furthermore, longer pre-adult duration in the late chronotypes does not lead to higher body-mass at pupariation or eclosion, but the late females were significantly more fecund and lived significantly shorter as compared to the early females. Conclusions: Coevolution of multiple life-history traits in response to selection on timing of eclosion highlights correlations of the genetic architecture governing timing of eclosion with that of fitness components which suggests that timing ecologically relevant behaviors at specific time of the day might confer adaptive advantage. [ABSTRACT FROM AUTHOR]

Studies on circadian entrainment have traditionally been performed under controlled laboratory conditions. Although these studies have served the purpose of providing a broad framework for our understanding of regulation of rhythmic behaviors under cyclic conditions, they do not reveal how organisms keep time in nature. Although a few recent studies have attempted to address this, it is not yet clear which environmental factors regulate rhythmic behaviors in nature and how. Here, we report the results of our studies aimed at examining (i) whether and how changes in natural light affect activity/rest rhythm and (ii) what the functional significance of this rhythmic behavior might be. We found that wild-type strains of fruit flies, Drosophila melanogaster, display morning (M), afternoon (A), and evening (E) peaks of activity under seminatural conditions (SN), whereas under constant darkness in otherwise SN, they exhibited M and E peaks, and under constant light in SN, only the E peak occurred. Unlike the A peak, which requires exposure to bright light in the afternoon, light information is dispensable for the M and E peaks. Visual examination of behaviors suggests that the M peak is associated with courtship-related locomotor activity and the A peak is due to an artifact of the experimental protocol and largely circadian clock independent. [ABSTRACT FROM AUTHOR]

To investigate whether circadian clocks in fruit flies Drosophila melanogaster evolve as a consequence of selection on the timing of adult emergence, we raised four replicate populations each of early (early1..4) and late (late1..4) emerging flies by selecting for adults that emerged during the morning and the evening hours. We estimated the percentage of flies that emerged during the two selection windows to evaluate the direct response to selection, and the circadian phenotypes of adult emergence and locomotor activity rhythms under light/dark (LD) and constant darkness (DD) to assess the correlated response to selection. After 55 generations, the percentage of flies emerging during the morning window increased in the early populations, but decreased in the late populations. The percentage of flies emerging during the evening window increased in the late populations, but decreased in the early populations. The time course and waveform of emergence and locomotor activity rhythms of the selected populations diverged from each other as well as from the controls. Further, the circadian periodicity of the early populations was significantly shorter than the controls, while that of the late populations was significantly longer than the controls. The light-induced phase response curve of the selected populations differed significantly within groups as well as from the controls. Such modifications in the circadian phenotypes of the selected populations due to heritable changes in genetic architecture, in response to imposed selection pressure, suggest that the circadian clocks underlying emergence and locomotor activity rhythms in D. melanogaster evolve as a correlated response to selection on the timing of adult emergence. [ABSTRACT FROM AUTHOR]

In this paper, we report the results of our extensive study on eclosion rhythm of four independent populations of Drosophila melanogaster that were reared in constant light (LL) environment of the laboratory for more than 700 generations. The eclosion rhythm of these flies was assayed under LL, constant darkness (DD) and three periodic light-dark (LD) cycles (T20, T24, and T28). The percentage of vials from each population that exhibited circadian rhythm of eclosion in DD and in LL (intensity of approximately 100 lux) was about 90% and 18%, respectively. The mean free-running period (τ) of eclosion rhythm in DD was 22.85 ± 0.87 h (mean ± SD). Eclosion rhythm of these flies entrained to all the three periodic LD cycles, and the phase relationship (ψ) of the peak of eclosion with respect to “lights-on” of the LD cycle was significantly different in the three periodic light regimes (T20, T24, and T28). The results thus clearly demonstrate that these flies have preserved the ability to exhibit circadian rhythm of eclosion and the ability to entrain to a wide range of periodic LD cycles even after being in an aperiodic environment for several hundred generations. This suggests that circadian clocks may have intrinsic adaptive value accrued perhaps from coordinating internal metabolic cycles in constant conditions, and that the entrainment mechanisms of circadian clocks are possibly an integral part of the clockwork. [ABSTRACT FROM AUTHOR]

Objective: Prevalence of hypertension was examined in a widely dispersed (45 110 km(2)) representative group of Ladakhi in Northern India. The influence of hypoxic environment of wide-ranged altitude (2600-4900 m) and lifestyle change on hypertension was studied., Methods: 2800 participants (age 20-94 years) were enrolled. Systolic blood pressure ≥140 mm Hg and/or diastolic blood pressure of ≥90 mm Hg and/or taking current anti-hypertensive medicine was defined as hypertension. Height and weight for body mass index and SpO₂ were examined. The rural population comprised six subdivisions with a distinct altitude, dietary and occupational pattern. Participants in the urban area of Leh consist of two groups, that is, migrants settled in Leh from the Changthang nomadic area, and dwellers born in Leh. The prevalence of hypertension in the two groups was compared with that in the farmers and nomads in rural areas. The effects of ageing, hypoxia, dwelling at high altitude, obesity, modernised occupation, dwelling in an urban area, and rural-to-urban migration to hypertension were analysed by multiple logistic regression., Results: The prevalence of hypertension was 37.0% in all participants and highest in migrants settled in Leh (48.3%), followed by dwellers born in Leh town (41.1%) compared with those in rural areas (33.5). The prevalence of hypertension in nomads (all: 27.7%, Tibetan/Ladakhi: 19.7/31.9%)) living at higher altitude (4000-4900 m) was relatively low. The associated factors with hypertension were ageing, overweight, dwelling at higher altitude, engagement in modernised sedentary occupations, dwelling in urban areas, and rural-to-urban migration. The effects of lifestyle change and dwelling at high altitude were independently associated with hypertension by multivariate analysis adjusted with confounding factors., Conclusions: Socioeconomic and cultural factors play a big role with the effect of high altitude itself on high prevalence of hypertension in highlanders in Ladakh., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)