218 research outputs found
Effects of dietary fat saturation on lipoprotein metabolism in rodents and humans
Consumption of trans-fatty acids (tFA) and saturated fatty acids (SFA) have been associated with higher incidence of coronary heart disease. Experimental and observational data suggests that consumption of PHVO containing tFA, like SFA leads to increased total cholesterol and LDL-cholesterol (LDL-C) but compared to tFA, SFA raises HDL-cholesterol (HDL-C). An attempt to eliminate PHVO from the food supply has resulted in the need to find alternatives which despite their higher dietary fat saturation as compared to naturally occurring vegetable oils, may be preferable to PHVO. However, amongst SFA, the effects on plasma lipoproteins are variable. Thus, we hypothesized that specific combinations of dietary SFA will not contribute to an adverse lipid profile.
We used gerbils and hamsters as our study models to determine the effects of Lauric and Myristic Acid (Hi-LM), Oleic Acid (Hi-OL), Palmitic Acid (Hi-PO), Linoleic Acid (Hi-LO Low-LN), Stearic acid and Linoleic Acid (Hi-SLO) supplemented diets on plasma and liver lipids and lipoproteins. The results revealed that compared to the Hi-LM diet, all diets had lower TC, LDL-C and HDL-C. Liver lipids were similar for all the diet groups. Also, we analyzed the gene expression for the reverse Cholesterol transport genes. No significant differences in ABCA1, ApoA1, CETP or SR-B1 were observed between the diet groups compared with Hi-LM diet. The data suggested no additional adverse effects on CHD risk factors compared with Hi-LM diet.
Carbohydrates are generally considered a safe replacement for SFA. We used a hamster model to evaluate the extent to which the amount and type of SFA affect lipoproteins. Diets were formulated such that percentage of calories from protein, MUFA and PUFA were kept constant while calories from Lauric and Myristic (60%LM, 45%LM, 30% LM) or Palmitic Acid (45%PA, 30% PA) were replaced with calories from carbohydrate and compared to 21% CON diet. Plasma TC and n-HDL-C was lower in all diet groups compared with 60%LM and 45% LM supplemented groups. Liver lipids were similar in all diet groups. Analysis of Reverse Cholesterol Transport genes revealed no significant differences in expression between the diet groups compared with 21% CON. Data suggests no adverse effect of PA at any level of consumption and no net effect of replacing CHO for at any level of SFA.
The postprandial state is a reflection of the metabolic state in humans due to regular diet intake. We used an oral challenge to test oils with various fatty acid compositions (Hi-PO, Hi-LO and Hi-OL) to evaluate postprandial changes in lipids at 0, 2, 4 and 8 hours. No significant differences were seen in TC, HDL-C, TC:HDL-C and TG between the test oils. We analyzed the chylomicron fractions following the oral fat challenge and data revealed no significant differences in the chylomicron fractions between the test oils. Additionally, we measured CETP activity in plasma following the challenge and no significant differences were observed. The data suggests in agreement with the hypothesis, oil formulations with specific SFA will not cause any adverse effects in lipids and lipoproteins
Antipsychotics - a key line treatment for various psychotic symptoms
âPsychosisâ is the state of mental disorder characterized by loss of contact with reality followed by delusions, hallucinations, disorganised thoughts etc. which mainly occurs because of the imbalance of neurotransmitters like dopamine, serotonin or glutamate. About 5-8% of people suffer from mental disorders in the whole world. In the earlier time it was difficult to treat such psychotic patients. So, when antipsychotics came in the market the treatment of such serious mental conditions became possible. Mainly two categories of antipsychotics are prescribed, out of which second generation are commonly prescribed because of their less adverse effects
Early lifestyle determinants of adiposity trajectories from childhood into late adolescence
Contexte: L'obĂ©sitĂ© infantile est un facteur de risque majeur de mortalitĂ© et de morbiditĂ©, car les enfants avec obĂ©sitĂ© ont tendance Ă maintenir leur obĂ©sitĂ© Ă lâĂąge adulte. Parmi les enfants canadiens, 27% ont un surpoids ou une obĂ©sitĂ©, ce qui pose un grave problĂšme de santĂ© publique, vu les consĂ©quences en termes de morbiditĂ© et mortalitĂ© de lâobĂ©sitĂ© Ă lâĂąge adulte. Objectifs: Les principaux objectifs de ma recherche sont les suivants: (1) examiner le lien entre l'activitĂ© physique durant la prĂ©-pubertĂ© et les trajectoires d'adipositĂ© de lâenfance Ă l'adolescence; (2) examiner le lien entre les comportements sĂ©dentaires dans la prĂ©-pubertĂ© et les trajectoires d'adipositĂ© de lâenfance Ă l'adolescence; et (3) examiner les associations entre les apports alimentaires dans la prĂ©-pubertĂ© et les trajectoires d'adipositĂ© de lâenfance Ă l'adolescence. Mon hypothĂšse est que moins d'activitĂ© physique, plus de temps sĂ©dentaire et une alimentation moins saine (ex. moins de fruits et lĂ©gumes, plus de boissons sucrĂ©es) pendant l'enfance seront associĂ©s Ă des trajectoires dĂ©favorables dâobĂ©sitĂ© de lâenfance Ă l'adolescence. MĂ©thodes: Cette recherche porte sur les donnĂ©es de lâĂ©tude QUALITY (QUebec Adipose and Lifestyle Investigation in Youth). Cette cohorte comprend 630 enfants caucasiens ĂągĂ©s de 8 Ă 10 ans, recrutĂ©s au dĂ©part sur la base dâantĂ©cĂ©dent d'obĂ©sitĂ© chez leurs parents. De ce nombre, 377 ont Ă©tĂ© suivis Ă 10-12 ans et Ă 15-17 ans. Les comportements sĂ©dentaires et l'activitĂ© physique ont Ă©tĂ© mesurĂ©s par accĂ©lĂ©romĂ©trie sur une pĂ©riode de 7 jours, le temps d'Ă©cran a Ă©tĂ© mesurĂ© par questionnaire et l'apport alimentaire avec trois rappels alimentaires de 24 heures. Le poids et la taille ont Ă©tĂ© mesurĂ©s Ă chaque pĂ©riode et transformĂ©s en scores z de l'indice de masse corporelle (IMC-z) selon les normes de l'OMS (Organisation Mondiale de la SantĂ©). La modĂ©lisation des trajectoires basĂ©e sur les groupes a Ă©tĂ© utilisĂ©e pour identifier les trajectoires longitudinales de l'IMC-z. Des rĂ©gressions logistiques multinomiales ont ensuite Ă©tĂ© utilisĂ©es pour examiner les associations entre les habitudes de vie durant lâenfance et les trajectoires dâadipositĂ©, en ajustant lâĂąge, le sexe, les stades du dĂ©veloppement pubertaire de Tanner et lâĂ©ducation parentale. RĂ©sultats principaux: Six trajectoires distinctes dâIMC-z ont Ă©tĂ© identifiĂ©es: Poids-Faible-Ă -Normal-Stable (5,7%), deux groupes de Poids-Normal-Stable qui ont ensuite Ă©tĂ© combinĂ©s (33,0% et 24,8%), Surpoids-Stable (19,8%), ObĂšse-Stable (8,8%) et Surpoids-DĂ©croissants (7,9%). Pour chaque portion supplĂ©mentaire de fruits et lĂ©gumes Ă 8-10 ans, la probabilitĂ© de faire partie du groupe en Surpoids-DĂ©croissants est augmentĂ©e de 26% (OR 1,26, IC 95% 1,06-1,49) par rapport Ă ceux du groupe Poids-Normal-Stable. Pour chaque heure supplĂ©mentaire de comportement sĂ©dentaire mesurĂ©e par l'accĂ©lĂ©romĂštre Ă 8-10 ans, la probabilitĂ© d'appartenir au groupe Surpoids-DĂ©croissants est augmentĂ©e de 51% (OR 1,51, IC Ă 95% 1,03- 2,22) par rapport au groupe Poids-Normal-Stable. En termes d'activitĂ© physique, toutes les 10 minutes supplĂ©mentaires d'activitĂ© physique modĂ©rĂ©e Ă vigoureuse (APMV) au dĂ©part Ă©taient associĂ©es Ă une probabilitĂ© plus faible d'appartenir au groupe ObĂšse-Stable (OR 0,75, IC Ă 95% 0,61-0,91) et Groupe Surpoids-DĂ©croissants (OR 0,78, IC 95% 0,62-0,98) par rapport au groupe Poids-Normal-Stable. Importance: Cette Ă©tude a permis dâidentifier diffĂ©rents groupes de trajectoires de dĂ©veloppement du score IMC-z qui restent stables de lâenfance Ă la fin de l'adolescence ainsi quâun groupe dâenfants qui sont passĂ©s d'un surpoids Ă un poids normal. Ces derniers avaient un apport alimentaire plus favorable en fruits et lĂ©gumes Ă 8-10 ans. Cependant, ils avaient Ă©galement une APMV infĂ©rieure et un comportement plus sĂ©dentaire comparativement au groupe de Poids-Normal-Stable.Background: Childhood obesity is a major risk factor for mortality and morbidity as children with obesity tend to remain obese into adulthood. Among Canadian children, 27 % have overweight or obesity, which is a serious public health concern. Objectives: The main objectives of my research are to (1) examine the associations between physical activity in pre-puberty or early puberty and obesity trajectories across childhood and adolescence; (2) examine the associations between sedentary behaviors in pre-puberty or early puberty and obesity trajectories across childhood and adolescence; and (3) to examine associations between dietary intake in pre-puberty or early puberty and obesity trajectories across childhood and adolescence. My hypothesis is that lower physical activity, more time spent in sedentary behaviours and unhealthy diets (e.g., higher sugar-sweetened beverage consumption, lower fruit and vegetable intake) in childhood (pre to early puberty) will be associated with adverse patterns of obesity into adolescence. Methods: This study uses data from the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) study. This cohort includes 630 Caucasian children aged 8-10 years, recruited at baseline based on a parental history of obesity. Of these, 377 were re-assessed at 10-12 years and at 15-17 years. Sedentary behavior and physical activity using 7-day accelerometry, self-reported screen time and dietary intake with three 24-hr diet recalls were measured. Weight and height were measured at each time period and transformed to body mass index (BMI) z-scores using WHO (World Health Organization) Standards. Group based trajectory modeling was used to identify longitudinal trajectories of z-BMI. Multinomial logistic regressions were used to examine associations between lifestyle behaviors at 8-10 years and distinct obesity trajectory groups, while adjusting for age, sex, tanner stage and parental education. Results: Six distinct z-BMI trajectory groups were identified: Stable-Low-Normal-Weight (5.7%), two Stable-Normal-Weight groups that were subsequently combined (33.0% and 24.8%), Stable-Overweight (19.8%), Stable-Obese (8.8%) and Overweight-Decreasers (7.9%). For every additional vegetable and fruit serving at baseline, the likelihood of being in the OverweightâDecreasers group increased by 26% (OR 1.26, 95% CI: 1.06, 1.49) compared to those in the Stable-Normal-Weight group. For every additional hour of sedentary behavior at baseline, the likelihood of belonging to the Overweight-Decreasers group increased by 51% (OR 1.51, 95% CI: 1.03, 2.22) as compared to Stable-Normal-Weight group. In terms of physical activity, every additional 10 mins of Moderate to Vigorous Physical Activity (MVPA) at baseline was associated with a lower likelihood of belonging to the Stable-Obese group (OR 0.75, 95% CI: 0.61, 0.91) and to the Overweight-Decreasers group (OR=0.78, 95% CI: 0.62, 0.98) compared to the Stable-Normal-Weight group. Conclusion: Stable trajectories of z-BMI from childhood to late adolescence were found, with the exception of one decreasing trajectory from overweight in childhood to normal weight in adolescence. The latter had more favourable dietary intake of fruits and vegetables at baseline, however, they also had lower MVPA and more sedentary behavior
Virtual learning environment for watershed science education
Environmental education has been evolving for many years. Today it has become imperative that the colleges and universities modify their curricula to impart the students with adequate knowledge of earth and environmental sciences. The revolution in information and communication technologies (ICTs) has shaken the foundations of higher education and life-long learning in general. Undergraduate education, utilizing these new technologies, which involves active student participation and inquiry based pedagogy, will be the key to developing a workforce and environmentally literate citizenry who can critically evaluate issues related to environment and natural resources. This research is focused towards the creation and development of a set of interactive, student centered, inquiry-based online learning modules, including simulation and visualization tools that enhance watershed ecosystem science education. The basic aim of this research was to create learning materials that lead students through problem-solving exercises involving real-world watershed management problems and integrates modern technologies to provide a richer vision of complex environmental processes and concepts
Feasibility of a Carbon Consumption Tax for sustainable development â A case study of India
Global climate change is a major issue confronting policymakers worldwide, and there is widespread scientific acceptance of the reality of climate change and its adverse consequences In terms of economic analysis, greenhouse gas emissions (GHG), which cause planetary climate changes, represent both an environmental externality and the overuse of a common property resource. The paper is premised around the hypothesis that tax policy can be used to address climate concerns by making less Green House Gas intensive purchases and investments more financially attractive. However, in the absence of an international framework capping GHG emissions, countries adopting mitigation policies incur costs that would not exist under global cooperation such as the loss of competitiveness and emissions leakage. A consumption tax based on the carbon footprint of a product levied on all products at the point of purchase by the final end-user, regardless of where the goods are produced using a Credit-method would be capable of addressing these concerns of emissions leakage and loss of competitiveness, while being WTO compliant. The author intends to test the feasibility and effectiveness of such a carbon consumption tax in the Indian Context. The author shall test the feasibility of levy of such a consumption tax in the context of India and evaluate the effectiveness in mitigating climate change and catering to the goal of sustainable development
Does Size Matter? An Investigation of Collaborative Information Technology Adoption by US Firms
We explore the adoption pattern of seven IT innovations to support taskoriented collaboration between group members working asynchronously or synchronously and the impact of two size-related variables, organization size and the size of the internal IT function, on the adoption of these seven IT innovations. IT adoption is viewed as a transition from the state of non-adoption to adoption (adoption status) and then to the extent of accessibility of the IT to organizational end-users (adoption level). Analysis of data collected from one hundred and eighteen U.S. organizations suggests that adoption patterns of the seven IT clusters vary considerably and that size (organization and IT function) is associated with the aggregate adoption status of the ITs investigated. Larger organizations with larger IT functions had adopted more of the ITs than their smaller counterparts. However, when exploring effects of size-related variables on adoption status of individual IT clusters, our findings suggest that size is associated with adoption of only those IT clusters that may require large resource infusions for acquisition, are fairly complex to use, and require substantial technical support. Size was not found to be associated with the adoption level of the majority of individual IT clusters. However, interestingly, at the aggregate level, our results suggest that once adopted, the IT clusters had higher adoption level in smaller organizations than their larger counterparts. Implications of these findings are discussed along with some directions for practice and research
Organizational Readiness for Business Intelligence and Analytics Systems Success
BI&A systems have the potential to improve business performance by facilitating innovations, creating new products and service, and enhancing decision making effectiveness. However, it requires certain technological and organizational capabilities to fully realize the values of BI&A systems. This study investigates how an organization needs to prepare itself to harvest from its investments in BI&A systems. We build a model using the contingency approach to test factors that affect the success of BI&A systems. The insights from this study can inform managers of business organizations about their organizational readiness for the success of their BI&A systems and identify best practices to implement BI&A systems in business organizations. It will also help advance our knowledge in how to accurately assess the success of BI&A systems
Generalizable improvement of the Spalart-Allmaras model through assimilation of experimental data
This study focuses on the use of model and data fusion for improving the
Spalart-Allmaras (SA) closure model for Reynolds-averaged Navier-Stokes
solutions of separated flows. In particular, our goal is to develop of models
that not-only assimilate sparse experimental data to improve performance in
computational models, but also generalize to unseen cases by recovering
classical SA behavior. We achieve our goals using data assimilation, namely the
Ensemble Kalman Filtering approach (EnKF), to calibrate the coefficients of the
SA model for separated flows. A holistic calibration strategy is implemented
via a parameterization of the production, diffusion, and destruction terms.
This calibration relies on the assimilation of experimental data collected
velocity profiles, skin friction, and pressure coefficients for separated
flows. Despite using of observational data from a single flow condition around
a backward-facing step (BFS), the recalibrated SA model demonstrates
generalization to other separated flows, including cases such as the 2D-bump
and modified BFS. Significant improvement is observed in the quantities of
interest, i.e., skin friction coefficient () and pressure coefficient
() for each flow tested. Finally, it is also demonstrated that the newly
proposed model recovers SA proficiency for external, unseparated flows, such as
flow around a NACA-0012 airfoil without any danger of extrapolation, and that
the individually calibrated terms in the SA model are targeted towards specific
flow-physics wherein the calibrated production term improves the re-circulation
zone while destruction improves the recovery zone
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