Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope

Lateral intakes are common in rivers.The pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division width.The hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be investigated.Meanwhile,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be clarified.Hence,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side bank.The flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel velocities.This study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this phenomenon.The average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank conditions.With a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical direction.Under inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope conditions.The results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains.

Studies on Human Dietary Requirements and Safe Range of Dietary Intakes of Selenium in China and Their Application in the Prevention of Related Endemic Diseases

The human dietary selenium requirement in China has been estimated by various methods. The minimum dietary selenium requircment for the prevention of Keshan disease (KD) was found to be around 17 μg/d. On the other hand, an intake of 40 μg/d is required to maintain the plasma glutathione peroxidase (GPx) activity at plateau. Hence 40 μg/d is considered as the adequate dietary selenium requirement. Studies conducted in a chronic selenosis area indicate thai the toxic dietary selenlum inlake (adverse effect level), which would maintain the characteristic fingernail changes, was approximately 1600 μg/d. The mean value of dietary selenium intakes, which enabled the five patients to recover from fingernail lesions, was found to be 819 ±126μg/d. At a 95% confidence limit, the lower limit is around 600μg/d. Therefore, 600 and 400μg/d were suggested as the individual daily maximum safe selenium intake and the safe dietary selenium intake, respectively,The results were used in the prevention of Se-related endemic KD and Kashin-Beck disease (KBD)

Comparison of dietary intakes of Canadian Armed Forces personnel consuming field rations in acute hot, cold, and temperate conditions with standardized infantry

Background:Dietary Reference Intakes are used to guide the energy intake of the Canadian Armed Forces(CAF)field rations provided to military personnel deployed for training or operations.However,the high energy expenditures likely to occur under harsh environmental/metabolically challenging deployment conditions may not be adequately considered.This study examined the Ad libitum energy and nutrient intakes of CAF personnel(n=18)consuming field rations in a resting thermoneutral environment and during a day of standardized strenuous infantry activities at varying environmental temperatures.Methods:Dietary intake was assessed using a measured food intake/food waste method during the experimental treatment and for 6 h after treatment.Four treatments were administered in a randomized counterbalanced design:exercise(as standardized infantry activities)in the heat(30℃),exercise in the cold(–10℃),exercise in temperate thermoneutral(21℃)air temperatures and a resting(sedentary)trial(21℃).Results:The average Ad libitum consumption of field rations was 70%of the provided total energy(2776±99 kcal/8 h)during all treatments.Even with an acute challenge of increased energy expenditure and temperature stress in the simulated field conditions,participants’energy intakes(1985±747 kcal/8 h)under hot,cold and temperate treatments did not differ from energy intake during the sedentary condition(1920±640 kcal/8 h).Participants’energy intakes(1009±527 kcal/6 h)did not increase during the 6 h posttreatment period when the stresses of the strenuous physical activities and the harsh environmental temperatures had subsided.Conclusions:These results should be considered when planning the provision of field rations for CAF personnel expected to be engaged in strenuous physical activities with prolonged exposure to temperature extremes.

Evaluation of the Dietary Reference Intakes for Japanese (2010 Edition): Recommended Protein, Pantothenic acid, Vitamin D, and Iron Intakes for Breast-Fed Infants Aged 6 - 11 Months

Objective: With regard to the 2010 edition of Dietary Reference Intakes for Japanese (DRIs-2010), we investigated whether the DRIs for two age groups, breast-fed infants aged 6-8 and 9-11 months, can be fulfilled for every nutrient in actual dietary practice. Design: We evaluated (1) whether the DRIs for all nutrients can be fulfilled in a formula with energy and protein exceeding their DRIs, (2) whether the DRIs for all nutrients can be fulfilled in a formula prepared in accordance with Japanese government-recommended weaning guidelines, and (3) what kinds of formulas can be prepared if the DRIs for all nutrients are fulfilled without referring to the weaning guidelines. Setting: Simulation of diet menu on the basis of published data in our university and survey of diet menu in a university hospital attached to a national medical school. Subjects: The three types of formulas were planned for ten days. Results: It was impossible to simultaneously fulfil the DRIs for 6 - 8-month-old infants concerning pantothenic acid, vitamin D, and iron and those for 9 - 11-month-old infants concerning these nutrients plus protein. Conclusion: According to the DRIs-2010, the DRI for all nutrients could not be fulfilled in an ingestible formula.

Effects of Ovariectomy and 17<i>β</i>-Estradiol Replacement on Dopamine D2 Receptors in Female Rats: Consequences on Sucrose, Alcohol, Water Intakes and Body Weight

Background: Mechanisms underlying overeating-induced obesity in post-menopausal woman include functional lack of 17β-estradiol dysregulating dopamine D2 receptors, thereby inducing food addiction, glucose craving or alcohol dependence through reward circuitry. This study aimed at further understanding 17β-estradiol and dopamine D2 receptors interferences in the etiology of woman obesity. Method: Seventy-two Wistar female rats weighing 200 - 205 g, individually-housed, were divided into non-ovariectomized control (C = 6 groups) and ovariectomized rats (OVX = 6 groups) which were concurrently subjected to the following treatments: Non-drug-treated (DMSO vehicle), 17β-estradiol (E2, 5 μg/kg, s.c.), sulpiride (SUL, 20 mg/kg, i.p.), bromocriptine (BR, 0.1 mg/kg, i.p.), E2 + SUL or E2 + BR, designating the 6 constitutive groups of either control or ovariectomy. Within each experimental group, consumption of different solutions (10% alcohol, 10% sucrose and water) as well as food intake and body weight were daily measured, for 10 consecutive days. Results: This study indicated that D2S was a specific inducer of alcohol and food intakes, but reduced sugar consumption. In addition, 17β- estradiol regulated the body weight set point, modulating D2S functions towards increased food intake at lower weights and decreased food intake at higher weights. D2S met the slow genomic actions induced by 17β-estradiol. Conversely, D2L inhibited alcohol and food intakes, but induced specifically sugar consumption, thereby regulating blood glucose levels and promoting energy expenditure in reducing body weight. Indeed, 17β-estradiol exerted a tonic inhibition on D2L which was released by OVX, exacerbating sugar intake and increasing body weight. D2L mediated the rapid metabolic effects of 17β-estradiol. Conclusion: Our results supported physiological data reporting that activation of the mostly expressed presynaptically D2S-class autoreceptors decreased dopamine release stimulating food intake, whereas activation of the predominantly postsynaptic isoform D2L receptors increased dopamine activity inhibiting food intake. Our studies indicated that 17β-estradiol acted on the two types of D2 receptors showing opposite functions to equilibrate energy intake vs. expenditure for weight set point regulation. Our data also supported biochemical findings reporting that 17β-estradiol induced D2 genes transcriptional regulation, thereby involving both types of D2 receptors in the etiology of obesity. The combined dysregulated effects of D2L and D2S receptors, as 17β-estradiol was lacking, would be causal factors underlying the etiology of obesity.

Assessment of Usual Fruit, Vegetable and Vitamin C Intakes in a Sample of Egyptian Children: Pilot Study

The objective was to create an Egyptian database on the contributors of fruit and vegetables in the diets of preschool children and to estimate the usual daily intakes of fruits, vegetables and vitamin C. A total of 59 healthy boys and girls aged 2.5 - 6 years attending day care centers in urban Giza governorate completed the study by interviewing their mothers on 6x non-consecutive days using the 24 h dietary recall. Participants were classified according to age, gender and socioeconomic class. Prevalence of daily consumptions of fruits and vegetables amounted to 22% and 54%, respectively of the total children. The daily intakes of fruits and vegetables averaged 117.5 and 56.4 g, respectively. The consumption of different types of fruits and vegetables was unevenly distributed by different personal and social variables. Estimated daily vitamin C supply from the diet was 38 mg per child, which satisfied the respective recommended nutrient intake (RNI) of 30 mg for the first six years of life. However, the diet of 15% of the children covered less than 75% of RNI. Top fruits contributing to vitamin C were oranges, guava, watermelon, pears and grapes. Extra foods such as chipsy was consumed by 81% of the children, contributed 18% to daily vitamin C supply and also 58.6 mg sodium. A multilevel intervention strategy is warranted for promoting daily fruit and vegetable intake and healthy eating in early childhood.

Effects of 17<i>β</i>-Estradiol on Dopamine D2 Receptors in Thiamine-Deficient Female Rats: Consequences on Sucrose, Alcohol, Water Intakes and Body Weight

Our previous studies showed that 17β-estradiol (E2) modulated dopamine D2 receptor in regulating body weight set-point. The aim of this study was to understand whether thiamine deficiency influenced the E2 modulation on dopamine D2 receptors, using bromocriptine mesylate (BR) and sulpiride (SUL) as selective central dopamine-D2 receptors agonist and antagonist respectively. We studied the E2-dopamine D2 receptors interferences in a 10-day thiamine-deficient female rats for which consumptions of water, sugar, alcohol and food were daily-recorded and their consequences on body weights assessed. Our results showed that the volume of water daily ingested doubled in thiamine-deficient female rats (OXT), while sugar and alcohol consumptions collapsed with decreased weight and food consumption. On the one hand, thiamine potentiated D2/BR activity (bromocriptine-activated D2 receptors) to induce sugar intake and inhibited the same D2/BR receptors to induce water intake. On the other hand, thiamine promoted D2/SUL receptors (sulpiride-inhibited D2 receptors) for enhanced alcohol intake, increased food consumption and weight gain. Taking together, thiamine modulated the actions of 17β-estradiol on both D2/BR and D2/SUL receptors activities.

Certain Grain Food Patterns Are Associated with Improved 2015 Dietary Guidelines Shortfall Nutrient Intakes, Diet Quality, and Lower Body Weight in US Adults: Results from the National Health and Nutrition Examination Survey, 2005-2010

Objective: The goal of this study was to identify commonly consumed grain food patterns in US adults (≥19 years old;N = 14,384) and compare nutrient intakes, with focus on 2015-2020 Dietary Guidelines’ shortfall nutrients, diet quality, and health parameters of those consuming various grain food patterns to those not consuming grains. Methods: This study conducted secondary analyses of the National Health and Nutrition Examination Survey, 2005-2010. Cluster analysis was used and identified 8 grain patterns: 1) no consumption of main grain groups, 2) crackers and salty snacks, 3) yeast breads and rolls, 4) cakes, cookies, and pies, 5) cereals, 6) pasta, cooked cereals and rice, 7) quick breads, and 8) mixed grains. Results: Adults consuming “cereals”, “pasta, cooked cereals and rice”, and “mixed grains” had a better diet quality compared to no grains. Consuming many, but not all, of the grain food patterns resulted in less saturated fat and lower added sugars. Adults consuming “cereals”, “pasta, cooked cereals and rice” and “quick breads” had greater dietary fiber intake vs. no grains group. Calcium intake was increased in the cereals group, while magnesium intake was greater in adults consuming “cereals” and “pasta, cooked cereals and rice” vs. no grains. Vitamin D (D2 + D3) intake was higher in adults consuming “cereals”, “pasta, cooked cereals and rice”, and “mixed grains” vs. no grain group. Adults consuming “pasta, cooked cereals and rice” had lower body weights (79.1 ± 0.7 vs. 82.5 ± 1.2 kg;P = 0.009) and waist circumference (95.2 ± 0.6 vs. 98.2 ± 1.0 cm;P = 0.004) in comparison to those consuming no grains. Conclusions: Certain grain food patterns are associated with greater 2015-2020 Dietary Guidelines’ shortfall nutrients, better diet quality and lower body weights in adults. Additionally, certain grain food patterns are associated with lower intake of nutrients to limit, including saturated fat and added sugars.

Trans Fatty Acid Levels in Foods and Intakes among Population Aged 3 Years and above in Beijing and Guangzhou Cities,China

Objective To understand the dietary intake levels of trans fatty acids （TFA） in a Chinese population and establish a basis for health risk assessment of trans fatty acids. Methods The TFA contents data of 2613 food items and food consumption data of 10,533 people aged 3 years and above in two large cities in China were matched and a simple assessment method was used to estimate the distribution of dietary TFA intake. Results The mean content of TFA was highest in margarine （1.68±0.83 g/100g）, followed by chocolate and candy （0.89±2.68 g/100g）, edible vegetable oils （0.86±0.82 g/100g）, milk （0.83±1.56 g/100g）, and bakery foods （0.41±0.91 g/100g）. TFA intake accounted for 0.34%, 0.30%, 0.32%, and 0.29% of the total energy intake in the 3-6, 7-12, 13-17, and 〉18 year age groups, respectively. Of the populations studied, 0.42% demonstrated TFA intakes （as percentage of energy intake） greater than 1%. The main sources of dietary TFA intake were edible vegetable oils, milk, mutton, and beef, and baked foods, which accounted for 49.8%, 16.56%, 12.21%, and 8.87%, respectively. Conclusion The current intake of TFA among concern regarding the threshold of TFA intake people in two cities did not appear to be of major health as the percentage of total energy recommended by the World Health Organization. Because most TFA were derived from industrially processed foods, the government should reinforce nutrition labeling and regulate food producers to further reduce TFA in food and to provide scientific instruction for consumers to make sound choices.

Correlation between intakes of carbohydrates,protein,and fat with random blood sugar levels in menopausal women

Objective: Carbohydrates, proteins, and fats are energy sources needed by the body for performing daily activities and generating primary energy substances. In women who have undergone menopause, the function of thyroid hormone in their body begins to decline and thus affects the ability of the body to produce energy. The purpose of this study was to determine the correlation between the intakes of carbohydrates, proteins, and fats and random blood sugar levels in menopausal women.Methods: This study was a correlational analytical research with a cross-sectional design, which was conducted in 72 menopausal women recruited by the purposive sampling technique. In this study, a 24-hour food recall form was used, and randomized blood sugar levels were measured using a glucometer. The analysis of the data was performed using a Pearson product moment and multiple linear regression.Results: Carbohydrates and fats together affected random blood sugar levels with an F-value of 25.810 and a p-value of 0.000.Meanwhile, adjusted R^2 showed the value of 0.411, indicating that the difference in the intake of carbohydrates and fats together affected random blood sugar levels by 41.1%.Conclusions: Intake of carbohydrates and fats affected random blood sugar levels, whereas the rest were influenced by other factors,and protein intake was unrelated to random blood sugar levels in menopausal women.

Nutrient Intakes from Food of Lactating Women Do Not Meet Many Dietary Recommendations Important for Infant Development and Maternal Health

Literature describing dietary intakes of lactating mothers in the United States (US) is limited and none of the existing studies attempts to identify whether dietary shortcomings of lactating mothers are distinct from those of women of childbearing age in the US. The first objective of this observational study was to comprehensively analyze the dietary intakes of lactating mothers in the US to determine whether nutrient intakes from food were sufficient to meet recommendations. The second objective was to compare these intakes to those of women of childbearing age in the US. Weekly 3-day food records were collected from subjects for six weeks in 2012-2013. Subject mean daily intakes of food groups, macronutrients, vitamins, minerals, carotenoids, and specific fats including omega-3 and omega-6 fatty acids were determined and compared to daily recommendations. Intakes were compared to US women using the 2009-2010 National Health and Nutrition Examination Survey. Fruit, vegetable, and dairy intakes of mothers were ≤50% of recommendations, resulting in 12 of 26 analyzed vitamins or minerals including potassium, iodine, chromium, choline, and vitamins A, D, and E having mean daily intakes below the Estimated Average Requirement. Vitamin D intake of subjects was 18% lower than US women, while most other nutrients showed intakes within 10% of each other between populations. Lactating women are not meeting the increased dietary needs associated with breastfeeding, supporting education initiatives and interventions specifically tailored to breastfeeding populations to increase intakes of vitamin D, vitamin E, iodine, biotin, carotenoids, and polyunsaturated fatty acids from food.

Changes in fat but not fruit and vegetable intakes linked with body weight change in Mexican women immigrants in Quebec

The objective of the present study was to identify dietary parameters for predicting body weight change (ΔBW) in Mexican-born women (Mexicans) following immigration to Quebec City, Canada. Methods: Changes in fruit (ΔF), vegetable (ΔV), fruit and vegetable (ΔFV), and fat (ΔFat) intake were assessed according to post-immigration periods (1-5 years, 6-10 years, 11-20 years) using a food frequency questionnaire (FFQ). Anthropometric measures were also conducted in 87 Mexicans (study group) and 88 native-born Quebecers (comparison group) aged 18-65 years. Associations were calculated using full and partial robust regression models adjusting for potential confounders (origin, education, income, age, length of residence in Quebec City). Results: There was no difference in ΔBW between the groups. Body weight (BW) increased significantly in both Mexican (5.5 ± 0.9 kg, P < 0.0001) and Quebec women (4.7 ± 0.8 kg, P < 0.0001). ΔBW was positively correlated with ΔFat (β = 0.03, P = 0.003), but not correlated with origin, ΔF, or ΔV. ΔBW was negatively associated with education (β = –4.33, P = 0.007) and positively associated with length of residence (β = 0.3, P = 0.003). Partial models indicated ΔF (β = –1.35, P β = –1.04, P = 0.0001), and ΔFV (β = –2.27, P < 0.0001) were associated with origin, whereas net annual household income (β = 0.16, P = 0.04) was positively associated with ΔFat. Conclusions: Change in body weight could be predicted by length of residence, education, and change in fat intake in Mexican immigrant women and native-born Quebecers whereas changes in fruit and vegetable intakes could be predicted by Mexican or Quebec origin.

Consistent prevalence of inadequate micronutrient intakes across six years of second-year medical school students

Background: The dietary behaviors of physicians and medical students are strongly associated with their nutrition counseling practices. Little research to date describes their dietary intakes and no recent studies have assessed the adequacy of their micronutrient intakes. As micronutrient imbalances are associated with a variety of chronic diseases, public guidelines target increasing dietary nutrient density. The purpose of this study was to identify micronutrient imbalances in the diets of medical students and determine whether intakes are becoming more compliant with dietary guidelines over time. Methods: From 2000 to 2006, 409 second-year Vanderbilt University medical students completed the Block Brief 2000 food frequency questionnaire prior to the required “Introduction to Clinical Nutrition” course. Nutrient data were compared to Dietary Reference Intake values. Results: Dietary intakes of male students were consistently inadequate for vitamin E, vitamin D, calcium, magnesium and potassium across the six cohorts. Despite a significant increase over time in the number of vegetable servings consumed, the intakes of female students revealed the same inadequacies, as well as inadequate folate and iron intakes. Multivitamin and multimineral supplementation, consumed regularly by 51% of students, closed the gap in meeting estimated micronutrient requirements, except vitamin E. Conclusions: These data can be used to inform the content of nutrition interventions for medical students focused on making optimal food selection choices as well as the content of nutrition education in the medical school curriculum. It is important to enhance medical students’ preparedness as fu- ture health care providers—not only to serve as role models for healthy dietary behaviors, but also to better recognize the nutrition needs of their future patients.

Dietary Intakes by Different Markers of Socioeconomic Status: A Cross-Sectional Study

Previous studies show that diet quality varies by socioeconomic gradient. We compared the influence of individual- and area-level socioeconomic characteristics on food choice behavior and dietary nutrient intakes in a cross-sectional survey. Daily nutrient intakes were calculated from a food frequency questionnaire. Participants comprised 4007 people (1915 men, 2092 women) aged 35 to 74 years. Socioeconomic measures included the area-based deprivation NZDep2001, gross household income, education level and the occupation-based New Zealand Socioeconomic Index (NZSEI96). Results: Nutrients expressed as their percentage contribution to total energy intakes and adjusted for age, gender and ethnicity, showed that intakes of cholesterol were higher in the lower income groups, and fibre, alcohol and calcium were lower compared to the highest income group. Similarly adjusted nutrients expressed as their contribution to total energy intakes showed lower alcohol intakes in the lower NZDep2001 classes compared to the highest NZDep2001 class. Lower fruit, cheese, wine, and spirit servings were found in both the lower income and NZDep2001 groups. Lower vegetables, milk and cereal servings were found in the lowest income group compared with the highest. Higher chicken, eggs and bread servings were found in the lowest NZDep2001 group compared to the highest NZDep2001 group. Few statistically significant associations were observed with the NZSEI96 or education. Conclusion: Income was more strongly associated with nutrient intakes and NZDep2001 with food group selections. Lower fruit, cheese, wine and spirit servings in the lower SES strata showed independent associations with income and NZDep2001. However, NZDep2001 and income appear to be measuring different elements of dietary intakes and food group servings, with income being associated with lower vegetable, milk and cereal servings, and increased dietary cholesterol and lower fibre, and calcium intakes and NZDep2001 with increased chicken, eggs and bread servings. More in depth, research into area-level determinants of diet is warranted.

Integrated multi-omics reveals the relationship between growth performance,rumen microbes and metabolic status of Hu sheep with different residual feed intakes

Residual feed intake(RFI)is a metric that provides a more accurate measure of feed efficiency.The lower the RFI,the higher the feed efficiency.The changes in the host microbiome and metabolome contribute to the greater feed efficiency of low RFI(LRFI)animals.The aim of this study was to explore the differences in rumen microorganisms,rumen metabolites and plasma metabolites of Hu sheep with differing RFI through the microbiome and metabolome.A total of 80 Hu sheep were used.The experiment consisted of a 15-d pretrial period and a 128-d experimental period.The RFI in the experimental period was calculated for all sheep,and the sheep were screened into high RFI(HRFI,n=8)and LRFI(n=8)groups.The HRFI and LRFI sheep did not differ in their initial and final body weights,average daily gain and body measurements,but the dry matter intake of LRFI sheep was significantly decreased(28.4%,P<0.001).The sheep with LRFI had higher digestibility of crude protein(P=0.010)and ether extract(P=0.010)compared to HRFI group.The concentrations of acetate(P=0.036),propionate(P=0.010),valerate(P=0.027)and total volatile fatty acids(P=0.048)in rumen of LRFI group were higher compared to HRFI group.The results of 16S rDNA sequencing indicated that the sheep with LRFI had higher proportions of Prevotella genus in rumen liquid(P=0.031).The rumen metabolome and plasma metabolome results showed that the citrate cycle,pyruvate metabolism and alanine,aspartate and glutamate metabolism processes were more active for sheep in LRFI group,which provided more energy substrate such as malic acid,oxoglutaric acid and citric acid.In conclusion,sheep with LRFI can utilize feed more efficiently,and the more active energy metabolism pathway and the production of energy substances may account for the higher feed efficiency.

Mercury levels and estimated total daily intakes for children and adults from an electronic waste recycling area in Taizhou, China: Key role of rice and fish consumption

In order to assess the potential health risks of Hg pollution, total mercury（T–Hg） and methyl mercury（Me Hg） concentrations were determined in air, dust, surface soil, crops, poultry,fish and human hair samples from an electronic waste（e-waste） recycling area in Taizhou,China. High concentrations of T–Hg and Me Hg were found in these multiple matrices, and the mean concentration was 30.7 ng/m3 of T–Hg for atmosphere samples, 3.1 μg/g of T–Hg for soil, 37.6 μg/g of T–Hg for dust, 20.3 ng/g of Me Hg for rice and 178.1 ng/g of Me Hg for fish,suggesting that the e-waste recycling facility was a significant source of Hg. The inorganic Hg（I–Hg） levels（0.84 μg/g） in hair samples of e-waste workers were much higher than that in the reference samples. Pearson＇s correlation coefficients showed that strong positive correlations（p 〈 0.01） between hair I–Hg and time staying in industrial area（r = 0.81） and between Me Hg and fish consumption frequency（r = 0.91）, imply that workers were mainly exposed to Hg vapor through long-time inhalation of contaminated air and dust, while other population mainly exposed to Me Hg through high-frequency fish consumption. The estimated daily intakes of Hg showed that dietary intake was the major Hg exposure source,and Hg intakes from rice and fish were significantly higher than from any other foods. The estimated total daily intakes（TDIs） of Me Hg for both children（696.8 ng/（kg·day）） and adults（381.3 ng/（kg·day）） greatly exceeded the dietary reference dose（Rf D） of 230 ng/（kg·day）,implying greater health risk for humans from Hg exposures around e-waste recycling facilities.

Effect of bank slope on the flow patterns in river intakes

In this work, we studied the dimensions of stream tube in the vertical as well as inclined bank conditions. Data were collected from both a physical model and a 3-D numerical model（SSIIM 2）. Equations for predicting stream tube dimensions were presented and compared with existing formulae. In comparison with vertical bank, it is found that inclining bank causes the bottom stream tube width to be greater than at the surface. The strength of secondary current formed at the entrance of branch channel is reduced. These changes in flow pattern can reduce the amount of sediment delivery into the intake.

Applications of Three-Dimensional LBM-LES Combined Model for Pump Intakes

Lattice Boltzmannmodel(LBM)in conjunction with an accurate Large Eddy Simulation(LES)technology was proposed to simulate various vortical structures and their evolutions in open pump intakes.The strain rate tensor in the LES model is locally calculated by means of non-equilibrium moments based on Chapman-Enskog expansion,and bounce-back scheme was used for non-slip condition on solid walls and reflection scheme for free surface.The presentedmodel was applied to investigate free-surface and wall-attached vortices for different water levels and flow rate.The vortex position,shapes and vorticities were predicted successfully under three flowing cases(i.e.critical water level(CWL),lower water level,lower flow rate),and the numerical velocity and streamline distribution were analyzed systematically.For CWL based on Froude number considering open channel flows,the shape and the location of various dynamic vortices were captured.Compare to the experimental results of CWL,more vortices were predicted for lower water level,and less vortices were observed for lower flow rate.The predicted velocities and vortex locations are in good agreement with the experimental of a small physical model.The comparisons demonstrated the feasibility and stability of above-mentioned model and numerical method in predicting vortex flows inside open pump intakes.

Formation of air-entraining vortices at horizontal intakes without approach flow induced circulation

The aim of this experimental study is to investigate the effects of hydraulic parameters on the formation of air-entraining vortices at horizontal intake structures without approach flow induced circulation. Six intake pipes of different diameters were tested in the study. The intake pipe to be tested was horizontally mounted to the front side of a large reservoir and then for a wide range of discharges experiments were conducted and critical submergences were detected with adjustable approach channel sidewalls. Empirical equations were derived for the dimensionless critical submergence as a function of the relevant dimensionless parameters. Available data is also checked for the possible scale effect. Then, these obtained equations were compared with the similar ones in the literature which showed a quite good agreement.