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Effect of Food Availability on the Physiological Responses to Water Deprivation in Ponies النص الكامل
2013
Norris, Moira L. | Houpt, Katherine A. | Houpt, T Richard
Six ponies were deprived of drinking water and food and compared over 24 hours with nondeprived ponies, ponies deprived of water but with food available, and ponies deprived of food but with water available. When food was eaten during water deprivation, plasma osmolality rose 4% from 284 mOsm/kg to 295 mOsm/kg. During water and food deprivation, plasma osmolality failed to rise, even over 24 hours, and usually fell. Packed cell volume was higher when food but not water was available. Food and/or water deprivation had no significant effect on plasma protein concentration. When food was available, the ponies drank three times more water (13.1 ± 2.1 kg) than when water but not food was available (3.5 ± 1.4 kg). Blood volume changes were calculated from packed cell volume and plasma protein data, and it was found that blood volume did not change significantly with deprivation. Urine volume did not vary with deprivation, but free water clearance changed significantly, falling when food but not water was available. Under these conditions, blood volume is maintained, but the mechanisms are not clear. When deprived of both drinking water and food, ponies failed to develop the hyperosmolality expected under these conditions. Water deprivation while food is available is a more powerful challenge to water and electrolyte homeostasis than deprivation of both food and water.
اظهر المزيد [+] اقل [-]The energy-water-food nexus: Strategic analysis of technologies for transforming the urban metabolism النص الكامل
2014
Villarroel Walker, R. | Beck, M.B. | Hall, J.W. | Dawson, R.J. | Heidrich, O.
Urban areas are considered net consumers of materials and energy, attracting these from the surrounding hinterland and other parts of the planet. The way these flows are transformed and returned to the environment by the city is important for addressing questions of sustainability and the effect of human behavior on the metabolism of the city. The present work explores these questions with the use of systems analysis, specifically in the form of a Multi-sectoral Systems Analysis (MSA), a tool for research and for supporting decision-making for policy and investment. The application of MSA is illustrated in the context of Greater London, with these three objectives: (a) estimating resource fluxes (nutrients, water and energy) entering, leaving and circulating within the city-watershed system; (b) revealing the synergies and antagonisms resulting from various combinations of water-sector innovations; and (c) estimating the economic benefits associated with implementing these technologies, from the point of view of production of fertilizer and energy, and the reduction of greenhouse gases. Results show that the selection of the best technological innovation depends on which resource is the focus for improvement. Urine separation can potentially recover 47% of the nitrogen in the food consumed in London, with revenue of $33 M per annum from fertilizer production. Collecting food waste in sewers together with growing algae in wastewater treatment plants could beneficially increase the amount of carbon release from renewable energy by 66%, with potential annual revenues of $58 M from fuel production.
اظهر المزيد [+] اقل [-]Veterinary antibiotics in food, drinking water, and the urine of preschool children in Hong Kong النص الكامل
2017
Li, Na | Ho, Keith W.K. | Ying, Guang-Guo | Deng, Wen-Jing
Due to the harmful effects of veterinary antibiotics (VAs) residues in food on children's health, urine samples from 31 preschool and primary school children were analyzed for 13 common VAs. Samples of raw and cooked pork, chicken, fish, milk and drinking water from the children's living areas were also analyzed for residual VAs. Urinalysis revealed one to four target antibiotics in 77.4% of the sample group, with concentrations as high as 0.36ng/mL. Norfloxacin and penicillin had the highest detection rates (48.4% and 35.5%, respectively), with median concentrations of 0.037 and 0.13ng/mL, respectively. The VA burden of children in HK was lower than that in Shanghai. Enrofloxacin, penicillin, and erythromycin were the most detected VAs in raw and cooked food. Only oxytetracycline was detected in terminal tap water, and none were detected in milk. Tetracycline and doxycycline hyclate were detected in organic eggs (up to 7.1ng/g) and regular eggs (up to 6.6ng/g), which were common in children's diets. Traditional Chinese cooking processes did not completely eliminate VAs, and the concentrations of some VAs increased, especially after frying and roasting. The estimated daily intake (EDI) results show that the contribution of dietary intake and that based on the urine concentrations of VAs were far below the acceptable daily intake (ADI). The EDIs from urine were significantly lower than those based on cooked foods. The highest level of achievement percentage (LAP) based on dietary consumption and urine concentrations were 39.7% and 1.79%, respectively, and thus current levels of exposure to VAs would not seem to pose a risk to children's health. However, harmful effects of residual VAs during developmental periods may occur with exposure to much lower doses than those considered harmful to adults, and further investigation of these emerging pollutants is urgently encouraged.
اظهر المزيد [+] اقل [-]Effects of water dilution, housing, and food on rat urine collected from the metabolism cage
1998
Lee, K.M. | Reed, L.L. | Bove, D.L. | Dill, J.A.
The objective of the study reported here was to investigate three factors that may affect the amounts of water consumed and urine excreted by a rat in the metabolism cage: water dilution, housing, and food. Young F344/N rats (eight per group) were used for all experiments. Food was withheld from rats before each 16-h urine collection, then rats were transferred into a metabolism cage. For trial A (water dilution), urine was collected from rats supplied with dyed water (0.05%,vol/vol). This was repeated three times over a 2-week period. Dye in water or urine was quantified, using a spectrophotometer. For trial B (housing), rats were individually housed in wire cages for 3 weeks before the first urine collection. Then they were group housed in the solid-bottom cage (four per cage). After 2 weeks of acclimation, urine collection was repeated. For trial C (food), one group of rats was provided with food, the other was not, during urine collection. About 8% of urine samples of small volume (less than or equal to 3 ml) from trial A were contaminated with drinking water up to 13% of volume. The average urine volume associated with individual housing was approximately twice as large as that associated with group housing. When food was provided during urine collection, rats consumed similar amounts of water but excreted significantly smaller amounts of urine than did rats without food. It was concluded that water dilution of a urine sample from a sipper bottle is relatively small; rats individually housed in wire caging before urine collection can consumed and excrete a larger quantity of water, compared with rats group housed in solid-bottom cages: and highly variable urine volumes are, in part, associated with lack of access to food during urine collection.
اظهر المزيد [+] اقل [-]Anaerobic co-digestion of source segregated brown water (feces-without-urine) and food waste: For Singapore context النص الكامل
2013
Rajagopal, Rajinikanth | Lim, Jun Wei | Mao, Yu | Chen, Chia-Lung | Wang, Jing-Yuan
The objective of this study was to evaluate the feasibility of anaerobic co-digestion of brown water (BW) [feces-without-urine] and food waste (FW) in decentralized, source-separation-based sanitation concept. An effort has been made to separate the yellow water (urine) and brown water from the source (using no-mix toilet) primarily to facilitate further treatment, resource recovery and utilization. Batch assay analytical results indicated that anaerobic co-digestion [BW+FW] showed higher methane yield (0.54–0.59L CH4/gVSadded) than BW or FW as a sole substrate. Anaerobic co-digestion was performed in the semi-continuously fed laboratory scale reactors viz. two-phase continuous stirred-tank reactor (CSTR) and single-stage sequencing-batch operational mode reactor (SeqBR). Initial 120d of operation shows that SeqBR performed better in terms of organic matter removal and maximum methane production. At steady-state, CODs, CODt, VS removals of 92.0±3.0, 76.7±5.1 and 75.7±6.6% were achieved for SeqBR at 16d HRT, respectively. This corresponds to an OLR of 2–3gCOD/Ld and methane yield of about 0.41L CH4/gVSadded. Good buffering capacity did not lead to accumulation of VFA, showing better process stability of SeqBR at higher loading rates. The positive findings show the great potential of applying anaerobic co-digestion of BW+FW for energy production and waste management. In addition, daily flush water consumption is reduced up to 80%. Decentralized, source-separation-based sanitation concept is expected to provide a practical solution for those countries experiencing rapid urbanization and water shortage issues, for instance Singapore.
اظهر المزيد [+] اقل [-]Prenatal and childhood arsenic exposure through drinking water and food and cognitive abilities at 10 years of age: A prospective cohort study النص الكامل
2020
Vahter, Marie | Skröder, Helena | Rahman, Syed Moshfiqur | Levi, Michael | Derakhshani Hamadani, Jena | Kippler, Maria
Our studies of children in a rural Bangladeshi area, with varying concentrations of arsenic in well-water, indicated modest impact on child verbal cognitive function at 5 years of age.Follow-up of arsenic exposure and children’s cognitive abilities at school-age.In a nested sub-cohort of the MINIMat supplementation trial, we assessed cognitive abilities at 10 years of age (n = 1523), using Wechsler Intelligence Scale for Children (WISC-IV). Arsenic in maternal urine and erythrocytes in early pregnancy, in child urine at 5 and 10 years, and in hair at 10 years, was measured using Inductively Coupled Plasma Mass Spectrometry.Median urinary arsenic at 10 years was 58 µg/L (range 7.3–940 µg/L). Multivariable-adjusted regression analysis showed that, compared to the first urinary arsenic quintile at 10 years (<30 µg/L), the third and fourth quintiles (30–45 and 46–73 µg/L, respectively) had 6–7 points lower Full developmental raw scores (B: −7.23, 95% CI −11.3; −3.18, and B: −6.37, 95% CI −10.5; −2.22, respectively), corresponding to ~0.2 SD. Verbal comprehension and Perceptual reasoning seemed to be affected. Models with children’s hair arsenic concentrations showed similar results. Maternal urinary arsenic in early pregnancy, but not late pregnancy, showed inverse associations with Full developmental scores (quintiles 2–4: B: −4.52, 95% CI −8.61; −0.43, B: −5.91, 95% CI −10.0; −1.77, and B: −5.98, 95%CI −10.2; −1.77, respectively, compared to first quintile), as well as with Verbal comprehension, Perceptual reasoning, and Processing speed, especially in girls (p < 0.05 for interaction of sex with Full developmental scores and Perceptual reasoning). In models with all exposure time points included, both concurrent exposure at 10 years and early prenatal exposure remained associated with cognitive abilities.Both early prenatal and childhood arsenic exposure, even at low levels (about 50 µg/L in urine), was inversely associated with cognitive abilities at school-age, although the estimates were modest.
اظهر المزيد [+] اقل [-]Optimizing extraction and analysis of pharmaceuticals in human urine, struvite, food crops, soil, and lysimeter water by liquid chromatography-tandem mass spectrometry النص الكامل
2017
Mullen, Rachel A. | Wigginton, Krista R. | Noe-Hays, Abraham | Nace, Kim | Love, Nancy G. | Bott, Charles B. | Aga, Diana S.
Human urine is an abundant, renewable resource that can be used as a valuable source of fertilizer because it is rich in nitrogen, phosphorus and potassium. As fertilizers derived from urine become more widely used, it is important to understand how excreted pharmaceuticals are transported from urine to the environment. Many pharmaceuticals are excreted from the human body in their native form; therefore, when urine is used as a fertilizer, biologically active pharmaceuticals can be released into the environment. The goal of this study was to develop sensitive methods for the analysis of pharmaceuticals in urine, struvite, lysimeter water, soil, and food crops using liquid chromatography with tandem mass spectrometry (LC-MS/MS). The ability to detect low levels of pharmaceutical residues in various environmental matrices will aid in assessing the potential risks associated with the field application of urine that is used to fertilize croplands. The optimized method reported in this paper, which utilizes solid phase extraction for sample clean-up and pre-concentration, offers analyte recoveries ranging from 29 to 112 percent, and detection limits ranging from 0.89 ng L⁻¹ to 0.0047 μg g⁻¹. The optimized extraction method provides intra-day and inter-day reproducibility of less than 10% for all analytes in all matrices investigated, with the exception for ciprofloxacin in urine. The use of isotope dilution for quantification proved necessary to compensate for matrix effects, especially in urine where matrix effects can range from about 21% to 79%. Overall, the method described here is robust and widely applicable to various types of environmental samples.
اظهر المزيد [+] اقل [-]Food intake, water intake, urine output, growth rate and wool growth of lambs accustomed to high or low intake of sodium chloride
1987
Hamilton, J.A. | Webster, M.E.D. (New England Univ., Armidale (Australia))
Lambs artificially reared were given either no salt supplement (LS lambs) or 2.0 g NaCl supplementation per kg body weight (HS lambs) by oral route from an early age. Growth rate of HS lambs, although relatively high, was significantly less than in LS lambs, owing mainly to HS lambs having a reduced food intake. Linear relationships between water and food intakes were maintained, but shifted to a new plane for the HS lambs. The high intake of NaCl caused water intake to increase, which appeared to be mostly used to excrete the NaCl through increased urine output. Lambs given a high intake of NaCl had a lower food intake, but the reasons for the reduction could not be defined in this experiment. Wool production was reduced, but not significantly, by a high intake of NaCl. Diarrhoea was observed on more than one occasion in HS lambs during the experimental period.
اظهر المزيد [+] اقل [-]Estimation of Arsenic Intake from Drinking Water and Food (Raw and Cooked) in a Rural Village of Northern Chile. Urine as a Biomarker of Recent Exposure النص الكامل
2015
Oscar Diaz | Rafael Arcos | Yasna Tapia | Rubén Pastene | Dínoraz Velez | Vicenta Devesa | Rosa Montoro | Valeska Aguilera | Miriam Becerra
The aim of this study was to estimate both the contribution of drinking water and food (raw and cooked) to the total (t-As) and inorganic (i-As) arsenic intake and the exposure of inhabitants of Socaire, a rural village in Chile´s Antofagasta Region, by using urine as biomarker. The i-As intake from food and water was estimated using samples collected between November 2008 and September 2009. A 24-hour dietary recall questionnaire was given to 20 participants. Drinking water, food (raw and cooked) and urine samples were collected directly from the homes where the interviewees lived. The percentage of i-As/t-As in the drinking water that contributed to the total intake was variable (26.8–92.9). Cereals and vegetables are the food groups that contain higher concentrations of i-As. All of the participants interviewed exceeded the reference intake FAO/OMS (149.8 µg∙i-As·day−1) by approximately nine times. The concentration of t-As in urine in each individual ranged from 78 to 459 ng·mL−1. Estimated As intake from drinking water and food was not associated with total urinary As concentration. The results show that both drinking water and food substantially contribute to i-As intake and an increased exposure risk to adult residents in contaminated areas.
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