140 research outputs found
LES, DNS, and RANS for the Analysis of High-Speed Turbulent Reacting Flows
A filtered density function (FDF) method suitable for chemically reactive flows is developed in the context of large eddy simulation. The advantage of the FDF methodology is its inherent ability to resolve subgrid scales (SGS) scalar correlations that otherwise have to be modeled. Because of the lack of robust models to accurately predict these correlations in turbulent reactive flows, simulations involving turbulent combustion are often met with a degree of skepticism. The FDF methodology avoids the closure problem associated with these terms and treats the reaction in an exact manner. The scalar FDF approach is particularly attractive since it can be coupled with existing hydrodynamic computational fluid dynamics (CFD) codes
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Mental Health Services in Louisiana School-Based Health Centers Post-Hurricanes Katrina and Rita
Following Hurricanes Katrina and Rita, Louisiana school-based health centers (SBHCs) were called on to respond to a sharp increase in mental health needs, especially for displaced students coping with grief, loss, trauma, and uncertainty. To assess the impact of the hurricanes on the students and the needs of SBHC mental health providers (MHPs), we surveyed MHPs in each of the SBHCs under the auspices of the Louisiana Department of Health and Hospitals, Office of Public Health. SBHC practitioners from around the state reported that mental health service utilization rose during the 2005–2006 school year, but utilization of services increased most significantly in schools receiving the majority of displaced students. Anxiety and adjustment problems were noted as increasing the most following the hurricanes. A multitude of other conditions was also reported. By the time of this survey in April 2006, the reported prevalence of most symptoms had declined, but all remained above their pre-hurricane levels. Selfreported needs of SBHC MHPs are also discussed in light of the major natural disasters
Fast Foods, Sweets and Beverage Consumption and Risk of Colorectal Cancer: A Case-Control Study in Jordan
Background: The effects of consuming fast foods, sweets and beverages on the development of colorectal cancer (CRC) are unclear. The aim of this case-control study was to assess possible associations between the consumption of different fast foods, sweets and beverages and CRC risk in a Jordanian population. Methods: Two hundred and twenty diagnosed CRC cases and 281 controls were enrolled. Diet history was obtained using a validated quantitative questionnaire. Results: Consumption of some types of fast food, and particularly falafel, was associated with an increased risk of developing CRC. Elevated risk was found for potato and corn chips with an AOR of 4.36 (95%CI: 1.24-15.28) for daily consumption and 3.33 (95%CI: 1.00-11.11) for ≥5 servings/week. Consuming 1-2 or >5 servings per week of fried potatoes or 2-3 servings per week of chicken in sandwiches also increased the risk while exposure to fresh tomato juice and hot pepper sauce on a monthly basis appeared to exert a protective effect. Conclusions: Consumption of fried fast food items was significantly linked with an increased risk of developing CRC in Jordan
Macro- and micronutrients consumption and the risk for colorectal cancer among Jordanians
OBJECTIVE:
Diet and lifestyle have been reported to be important risk factors for the development of colorectal cancer (CRC). However, the association between total energy and nutrient intake and the risk of developing CRC has not been clearly explained. The aim of our study is to examine the relationship between total energy intake and other nutrients and the development of CRC in the Jordanian population.
RESEARCH METHODS AND PROCEDURES:
Dietary data was collected from 169 subjects who were previously diagnosed with CRC, and 248 control subjects (matched by age, gender, occupation and marital status). These control subjects were healthy and disease free. Data was collected between January 2010 and December 2012, using interview-based questionnaires. Logistic regression was used to evaluate the association between quartiles of total energy, macro- and micronutrient intakes with the risk of developing CRC in our study population.
RESULTS:
Total energy intake was associated with a higher risk of developing CRC (OR = 2.60 for the highest versus lowest quartile of intake; 95% CI: 1.21-5.56, p-trend = 0.03). Intakes of protein (OR = 3.62, 95% CI: 1.63-8.05, p-trend = 0.002), carbohydrates (OR = 1.41, 95% CI: 0.67-2.99, p-trend = 0.043), and percentage of energy from fat (OR = 2.10, 95% CI: 0.38-11.70, p-trend = 0.009) significantly increased the risk for the development of CRC. Saturated fat, dietary cholesterol and sodium intake showed a significant association with the risk of developing CRC (OR = 5.23, 95% CI: 2.33-11.76; OR = 2.48, 95% CI: 1.18-5.21; and OR = 3.42, 95% CI: 1.59-7.38, respectively), while vitamin E and caffeine intake were indicative of a protective effect against the development of CRC, OR = 0.002 (95% CI: 0.0003-0.011) and 0.023 (95%CI: 0.008-0.067), respectively.
CONCLUSION:
Our results suggest an increased risk for the development of CRC in subjects with high dietary intake of energy, protein, saturated fat, cholesterol, and sodium, and diets high in vitamin E and caffeine were suggestive of a protective effect against the risk of developing CRC.
IMPACT:
This is the first study in Jordan to suggest that it may be possible to reduce CRC risk by adjusting the intake of some macro-and micronutrients.Higher Council of Science and Technolog
Identifying a Milk-Replacer and Weaning Strategy for Holstein Calves Using Automated Behavioral Measures of Lying and Environmental Enrichment Device Use
In dairy production, “weaning readiness” is often based on solid feed intake. The goal of this study was to determine weaning readiness using feed-intake, lying-behaviors, and the use of an environmental enrichment device (EED) in calves that underwent 1 of 4 milk-replacer and weaning protocols. Twenty-eight male Holstein calves (95 ± 2.6 lb BW at 1 d of age) were housed in individual pens and initially fed one type of milk replacer (25% crude protein (CP), 17% fat, 1.45 lb of dry matter (DM)) via nipplebuckets twice a day (AM and PM), and one type of textured calf starter (ad libitum; 20% CP and 37% starch). At age 3 days, calves were randomly assigned to one of the four nutrition-weaning strategies:1. MOD-STEP - 1.46 lb per day of milk replacer; 2-step weaned, initiated at age 6 weeks, completed 3 days later; 2. HI-STEP - 2.4 lb per day of milk replacer; 2-step weaned, initiated at age 5 weeks and completed 1 week later; 3. HI-LATE - 2.4 lb per day of milk replacer; 2-step weaned, initiated at age 7 weeks and completed 1 week later; and 4. HI-GRAD - 2.4 lb per day of milk replacer; 5-step weaned, initiated at age 6 week and completed 2 weeks later.
Each calf’s pen had an EED, which included a dummy-nipple attached to a bottle and holder. A sensor and automated logger tracked each event (1 Hz) that the calf manipulated the EED (25 Hz sensitivity). Each calf was fitted with an accelerometer on the back leg to automatically measure lying behaviors. The device collected the y-axis (lie vs. stand) and z-axis (right or left percent during lying) of the calf every minute. For this experiment, 3-day sample periods were analyzed before and after weaning was initiated. In addition, the 3 days following weaning-completion were sampled.
Feed intake among MOD-STEP calves increased by 1.0 ± 0.19 lb after the first bottle was removed (P ≤ 0.05), and then by 1.5 ± 0.19 SE lb after completion of weaning (P ≤ 0.05). The use of EED did not change among MOD-STEP calves (P \u3e 0.05), but after weaning, they increased their lying time, especially on their left side (P ≤ 0.05). These changes in lying-behaviors may indicate increased comfort and maturity of the rumen. On the contrary, calves in the HI-STEP treatment ate the least amount of feed overall (P \u3c 0.05), and they used the EED the most (P \u3e 0.05). Calves in the HI-STEP treatment showed reduced lying bouts after weaning (P ≤ 0.05), but no other lying-measures changed (P \u3e 0.05).
The HI-LATE calves had similar feed intake and EED use compared to MOD-STEP calves. These findings suggest that weaning age needs to be more than 8 weeks for calves fed 2.4 lb of milk replacer per day. Gradual weaning may also improve feed intake and reduce EED use. When calves were gradually weaned starting at age 6 weeks and completed at age 8 weeks, they had the same amount of solid feed intake as HI-LATE calves. More research is needed to determine if increased feed intake and reduced EED use are also indicators that cross-sucking is less likely to occur when calves are grouped after weaning
Clay calcination technology: state-of-the-art review by the RILEM TC 282-CCL
The use of calcined clays as supplementary cementitious materials provides the opportunity to significantly reduce the cement industry’s carbon burden; however, use at a global scale requires a deep understanding of the extraction and processing of the clays to be used, which will uncover routes to optimise their reactivity. This will enable increased usage of calcined clays as cement replacements, further improving the sustainability of concretes produced with them. Existing technologies can be adopted to produce calcined clays at an industrial scale in many regions around the world. This paper, produced by RILEM TC 282-CCL on calcined clays as supplementary cementitious materials (working group 2), focuses on the production of calcined clays, presents an overview of clay mining, and assesses the current state of the art in clay calcination technology, covering the most relevant aspects from the clay deposit to the factory gate. The energetics and associated carbon footprint of the calcination process are also discussed, and an outlook on clay calcination is presented, discussing the technological advancements required to fulfil future global demand for this material in sustainable infrastructure development
Direct Numerical Simulation of Turbulent Heat Transfer Modulation in Micro-Dispersed Channel Flow
The object of this paper is to study the influence of dispersed micrometer
size particles on turbulent heat transfer mechanisms in wall-bounded flows. The
strategic target of the current research is to set up a methodology to size and
design new-concept heat transfer fluids with properties given by those of the
base fluid modulated by the presence of dynamically-interacting,
suitably-chosen, discrete micro- and nano- particles. We run Direct Numerical
Simulation (DNS) for hydrodynamically fully-developed, thermally-developing
turbulent channel flow at shear Reynolds number Re=150 and Prandtl number Pr=3,
and we tracked two large swarms of particles, characterized by different
inertia and thermal inertia. Preliminary results on velocity and temperature
statistics for both phases show that, with respect to single-phase flow, heat
transfer fluxes at the walls increase by roughly 2% when the flow is laden with
the smaller particles, which exhibit a rather persistent stability against
non-homogeneous distribution and near-wall concentration. An opposite trend
(slight heat transfer flux decrease) is observed when the larger particles are
dispersed into the flow. These results are consistent with previous
experimental findings and are discussed in the frame of the current research
activities in the field. Future developments are also outlined.Comment: Pages: 305-32
Multipoint genome-wide linkage scan for nonword repetition in a multigenerational family further supports chromosome 13q as a locus for verbal trait disorders
Verbal trait disorders encompass a wide range of conditions and are marked by deficits in five domains that impair a person’s ability to communicate: speech, language, reading, spelling, and writing. Nonword repetition is a robust endophenotype for verbal trait disorders that is sensitive to cognitive processes critical to verbal development, including auditory processing, phonological working memory, and motor planning and programming. In the present study, we present a six-generation extended pedigree with a history of verbal trait disorders. Using genome-wide multipoint variance component linkage analysis of nonword repetition, we identified a region spanning chromosome 13q14–q21 with LOD = 4.45 between 52 and 55 cM, spanning approximately 5.5 Mb on chromosome 13. This region overlaps with SLI3, a locus implicated in reading disability in families with a history of specific language impairment. Our study of a large multigenerational family with verbal trait disorders further implicates the SLI3 region in verbal trait disorders. Future studies will further refine the specific causal genetic factors in this locus on chromosome 13q that contribute to language traits. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00439-016-1717-z) contains supplementary material, which is available to authorized users
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