Quantifying cumulative effectiveness of green stormwater infrastructure in improving water quality.

Stormwater runoff is one of the main sources of pollution in streams and receiving water bodies of major cities. Green Stormwater Infrastructure (GSI) is a set of distributed stormwater best management practices that absorb excess water, filter out sediment and pollutants, and help recharge groundwater. Despite the increasing popularity of GSI as means of stormwater management, our knowledge of their cumulative performance is limited. In this research, we apply an empirical approach to study the effectiveness of GSI in improving the water quality of four major receiving water bodies of Seattle, Washington, at the watershed scale. We use a Bayesian structural time series model and synthetic control method to build counterfactual scenarios of water quality in absence of GSI implementation and estimate the causal impact of GSI on water quality. We use monthly time series data of water quality parameters (water temperature, dissolved oxygen, surface PAR, chlorophyll a, Secchi depth, pH, light transmission, and fecal coliform) in Seattle's urban watersheds from 2004 to 2017. We also use a set of nine control variables to estimate the counterfactual water quality parameters. Our findings show that GSI improve some water quality parameters such as chlorophyll a, light transmission and Secchi depth, but increase water temperature and decrease dissolved oxygen in some water bodies.

In patients with HIV-infection, chromium supplementation improves insulin resistance and other metabolic abnormalities: a randomized, double-blind, placebo controlled trial.

Chromium is an essential micronutrient; chromium deficiency has been reported to cause insulin resistance, hyperglycemia and hyperlipidemia. The aim was to investigate the effect of chromium supplementation on insulin-resistance, other metabolic abnormalities, and body composition in people living with HIV. This was a randomized, double-blind, placebo-controlled trial. Fifty-two HIV-positive subjects with elevated glucose, lipids, or evidence of body fat redistribution, and who had insulin-resistance based on the calculation of homeostasis model of assessment (HOMA-IR > or = 2.5) were assessed. Subjects who were on insulin or hypoglycemic medications were excluded. Subjects were randomized to receive either 400 microg/day chromium-nicotinate or placebo for 16 weeks. Forty-six subjects, 23 in each group, completed the study. Fasting blood insulin, glucose, lipid profile and body composition were measured before and after intervention. Chromium was tolerated without side effects and resulted in a significant decrease in HOMA-IR (median (IQR) (pre:4.09 (3.02-8.79); post: 3.66 (2.40-5.46), p=0.004), insulin (pre: 102 (85-226); post: 99 (59-131) pmol/L, p=0.003), triglycerides, total body fat mass (mean+/-SEM) (pre: 17.3+/-1.7; post: 16.3+/-1.7 kg; p=0.002) and trunk fat mass (pre: 23.8+/-1.9; post: 22.7+/-2.0 %; p=0.008). Blood glucose, C-peptide, total, HDL and LDL cholesterol, and hemoglobin A1c remained unchanged. Biochemical parameters did not change in the placebo group except for LDL cholesterol which increased significantly. Body weight and medication profile remained stable throughout the study for both groups. In summary, chromium improved insulin resistance, metabolic abnormalities, and body composition in HIV+ patients. This suggests that chromium supplements alleviate some of the antiretroviral-associated metabolic abnormalities.

Dietary intake and physical activity in a Canadian population sample of male patients with HIV infection and metabolic abnormalities.

Objective was to assess dietary intake and physical activity in a Canadian population sample of male patients with HIV and metabolic abnormalities and to compare the data to Canadian recommendations. Sixty-five HIV-infected men with at least one feature associated with the metabolic syndrome (insulin resistance, dyslipidemia, central obesity, or lipodystrophy) were enrolled. Results from 7-day food records and activity logs were compared to the Dietary Reference Intakes and recommendations of Canada's Physical Activity Guide, respectively. Anthropometric data were also measured. Fifty-two percent of the subjects were overweight, another 15% were obese. However, energy intake (mean+/-SEM) (2153+/-99 kcal/d) was lower than the estimated requirement (2854+/-62 kcal/d; p<0.0001), and 84.5% of the patients reached the recommended minimum of 60 min of mild or 30 min of moderate daily exercise. Intake was adequate for protein, but high for fat and cholesterol in 40% of patients. No patient reached the recommendation for fiber. Intake from diet alone was suboptimal for most micronutrients. Prevalence was highest for low vitamin E (91% of patients) and magnesium (68%) intake, and high sodium intake (72%). In summary, a large proportion of HIV patients with metabolic abnormalities were overweight or obese. However, this was not associated with high energy intake, or reduced physical activity. High fat, low fiber and inadequate micronutrient intakes were prevalent.

Nutritional assessment and hepatic fatty acid composition in non-alcoholic fatty liver disease (NAFLD): a cross-sectional study.

BACKGROUND/AIMS: Low hepatic n-6 and n-3 polyunsaturated fatty acid (PUFA) may contribute to steatosis and steatohepatitis and can be affected by diet and oxidative stress. METHODS: Seventy-three patients referred for elevated liver enzymes and suspected NAFLD were assessed. Nutritional assessment, hepatic FA composition and oxidative stress were compared between these groups: simple steatosis (SS, n=18), steatohepatitis (NASH, n=38) and minimal findings on liver biopsy (MF, n=17). RESULTS: Patients with NASH had higher: BMI, central obesity, body fat, insulin resistance, dyslipidemia and lower physical activity compared to the other groups. They also had relatively lower hepatic n-3 and n-6 PUFA, a decrease in the ratio of metabolites to essential FA precursors for both n-6 and n-3 FA (eicosapentaenoic+docosahexaenoic/linolenic and arachidonic/linoleic acid ratios) and higher liver lipid peroxides with lower antioxidant power, when compared to MF. Overall, there was no significant difference between SS and NASH in FA composition. Self-reported dietary intake and red blood cell FA composition were similar among the three groups. CONCLUSIONS: NASH patients have more metabolic abnormalities. This is associated with higher oxidative stress and lower n-3 and n-6 PUFA in the liver in the absence of any differences in dietary FA composition.