Search

The accurate evaluation of denitrification rate and greenhouse gas (GHG) emission in field-scale woodchip bioreactors for onsite wastewater treatment are problematic due to inevitably varied environmental conditions and underestimated GHG production with limited analysis of dissolved gas in field samples. To address these problems, batch incubation experiments were conducted with controlled conditions to precisely evaluate the denitrification kinetics and N 2 O and CH 4 emission of both gaseous and dissolved phases in fresh (6 months) and aged (5 years) woodchip bioreactors treating onsite wastewater at high (1-3 mg L -1 ) and no (0 mg L -1 ) dissolved oxygen (DO) levels. NO 3 - removal rate decreased from 37.5-119.0 g NO 3 - -N m -3 d -1 at no DO to 8.8-16.6 g NO 3 - -N m -3 d -1 at high DO (1-3 mg L -1 ) due to the growth suppression of NO 2 - reducing microorganisms (37-55 % lower nirS+nirK abundance). However, the presence of high DO increased N 2 O emission level from 5.6-6.9 mg N 2 ON m -3 at no DO to 179.5-273.6 mg N 2 -C m -3 ) due to the enhanced growth of NO reducing microorganisms (1-7 times higher norB levels) and the decreased abundance of N 2 O reducing microorganisms (53-75 % lower nosZ abundance). On the other hand, increased DO level negatively correlated with CH 4 production (1.0-3.9 g CH 4 -C m -3 d -1 ) in fresh woodchips, while showed insignificant impact on CH 4 production (0.1-1.4 g CH 4 -C m -3 d -1 ) in aged woodchips. Woodchip age increase (5 years) negatively impacted the NO 3 - removal rate (75-85 % lower than fresh woodchips) and CH 4 production rate (>3 times lower than fresh woodchips), probably due to the reduced biomass density of NO 2 - reducing microorganisms (52-58 % lower nirS+nirK abundance) and methanogens (95-98 % lower mcrA levels). The incubation results suggested that long hydraulic retention time (>2-5 days) and anaerobic/anoxic condition are preferred for the optimal NO 3 - removal and low N 2 O emission potential of woodchip bioreactors treating onsite wastewater., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Xinwei Mao reports financial support was provided by New York State Department of Environmental Conservation. Xinwei Mao reports financial support was provided by National Science Foundation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Our objective was to optimize a novel damage control resuscitation (DCR) cocktail composed of hydroxyethyl starch, vasopressin, and fibrinogen concentrate for the polytraumatized casualty. We hypothesized that slow intravenous infusion of the DCR cocktail in a pig polytrauma model would decrease internal hemorrhage and improve survival compared with bolus administration., Methods: We induced polytrauma, including traumatic brain injury (TBI), femoral fracture, hemorrhagic shock, and free bleeding from aortic tear injury, in 18 farm pigs. The DCR cocktail consisted of 6% hydroxyethyl starch in Ringer's lactate solution (14mL/kg), vasopressin (0.8U/kg), and fibrinogen concentrate (100mg/kg) in a total fluid volume of 20mL/kg that was either divided in half and given as two boluses separated by 30 minutes as control or given as a continuous slow infusion over 60 minutes. Nine animals were studied per group and monitored for up to 3 hours. Outcomes included internal blood loss, survival, hemodynamics, lactate concentration, and organ blood flow obtained by colored microsphere injection., Results: Mean internal blood loss was significantly decreased by 11.1mL/kg with infusion compared with the bolus group (p = .038). Survival to 3 hours was 80% with infusion and 40% with bolus, which was not statistically different (Kaplan Meier log-rank test, p = .17). Overall blood pressure was increased (p < .001), and blood lactate concentration was decreased (p < .001) with infusion compared with bolus. There were no differences in organ blood flow (p > .09)., Conclusion: Controlled infusion of a novel DCR cocktail decreased hemorrhage and improved resuscitation in this polytrauma model compared with bolus. The rate of infusion of intravenous fluids should be considered as an important aspect of DCR., (2023.)

The presence and release of 1,4-dioxane to groundwater from onsite-wastewater treatment systems (OWTS), which represent 25% of the total wastewater treatment in the U.S., has not been studied to date. In this study we monitored 1,4-dioxane in six septic tank effluents (STE) and receiving OWTS installed at residences on Long Island (LI), NY, for a period of 15 months. We specifically evaluated the performance of Nitrogen Removing Biofilters (NRBs) as an innovative/alternative-OWTS, consisting of a top sand layer and a bottom woodchip/sand layer, to simultaneously remove nitrogen and 1,4-dioxane. 1,4-Dioxane levels in STE (mean: 1.49 μg L -1 ; range: 0.07-8.45 μg L -1 ; n = 37) were on average > 15 times higher than tap water from these residences, demonstrating that 1,4-dioxane primarily originated from the use of household products. NRBs were effective in removing both 1,4-dioxane and total nitrogen with an overall removal efficiency of 56 ± 20% and 88 ± 12%, respectively. The majority of 1,4-dioxane removal (~80%) occurred in the top oxic layer of the NRBs. The detection of functional genes (dxmB, prmA, and thmA), which encode for metabolic and co-metabolic 1,4-dioxane degradation, in NRBs provides the first field evidence of aerobic microbial degradation of 1,4-dioxane occurring in a wastewater system. Given that there are ~500,000 conventional OWTS on LI, the 1,4-dioxane discharge to groundwater from residential wastewater was estimated at 195 ± 205 kg yr -1 , suggesting high risk of contamination to shallow aquifers. The results also demonstrate that installation of NRBs can reduce 1,4-dioxane to levels even lower than the NY State drinking water standard of 1 μg L -1 ., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

The activities of solutes and solvents in solutions govern numerous physical phenomena in a wide range of practical applications. In prior work, we used statistical mechanics and multilayer adsorption isotherms to develop a transformative model for capturing thermodynamic properties of multicomponent aqueous solutions over the entire concentration range (Dutcher et al. J. Phys. Chem. 2011, 2012, 2013). That model needed only a few adsorption energy values to represent the solution thermodynamics of each solute. In the current work, we posit that the adsorption energies are due to dipole-dipole electrostatic forces in solute-solvent and solvent-solvent interactions. This hypothesis was tested in aqueous solutions on (a) 37 1:1 electrolytes, over a range of cation sizes, from H(+) to tetrabutylammonium, for common anions including Cl(-), Br(-), I(-), NO3(-), OH(-), ClO4(-), and (b) 20 water-soluble organic molecules including alcohols and polyols. For both electrolytes and organic solutions, the energies of adsorption can be calculated with the dipole moments of the solvent, molecular size of the solvent and solute, and the solvent-solvent and solvent-solute intermolecular bond lengths. Many of these physical properties are available in the literature, with the exception of the solute-solvent intermolecular bond lengths. For those, predictive correlations developed here enable estimation of solute and solvent solution activities for which there are little or no activity data.

Background: In Peru, the incidence of primary focal segmental glomerulosclerosis (PFSGS) has considerably increased in the last decade and at the present; it is the first cause of primary glomerulonephritis in adults. Because of its prevalence and high probability to progress to end-stage renal disease (ESRD), we searched for factors with prognostic value for renal survival and proteinuria remission., Subjects and Methods: Historical cohort of 44 patients. We studied clinical and histological characteristics at the time of renal biopsy and clinical condition and renal function at the end of follow-up. PRINCIPAL OUTCOMES: renal impairment (increase >or=50% of basal creatinine levels and/or ESRD), proteinuria remission (partial 0.3-3.49 g/day and complete < 0.3g/day). Kaplan-Meier's curves and Cox's Multivariate Regression were used., Results: The 59% of patients were men. The 54.5% had renal failure, 53.5% nephrotic syndrome and 43.2% hypertension or high blood pressure (HBP) at renal biopsy. The frequency of histological variants was: not otherwise specified (NOS) 75%, cellular 13.6%, tip 6.8% and perihilar 4.5%. The 56.8% received steroids for 4.3 +/- 4.5 months and 32% of these patients were corticodependent. After a mean follow-up of 21.6 +/- 27.8 months, the renal function decreased in 18.2% of patients. The 37.8% and 32.4% of patients reached partial and complete proteinuria remission respectively. Treatment with steroids, antihypertensive therapy and IgM and C3 glomerular deposits were associated with a high renal survival. The treatment with steroids was the only factor that forecasted a high renal survival (hazard ratio or HR: 0.07, 0.01-0.9) and proteinuria remission (HR: 0.2, 0.04-0.9). In general, high blood pressure (HR: 6.2, 1.1-35.2), renal failure (HR: 2.9, 1.1-7.6), cellular variant and interstitial fibrosis (HR: 5.2, 1.02-26.7) were prognostic factors for not achieving proteinuria remission., Conclusions: In primary focal segmental glomerulosclerosis, treatment with steroids forecasted a high renal survival and proteinuria remission. Renal failure and interstitial fibrosis were prognostic factors for not achieving proteinuria remission.

Aim: We performed both a retrospective and prospective study to elucidate the types of glomerular diseases present in adults in Lima, Peru., Material and Methods: In the retrospective study, we analyzed 1,263 renal biopsies over a 10-year period (1985 -1995) that were processed at a central reference renal pathology laboratory in Lima. 101 cases were examined in the prospective study., Results: The most common glomerular diseases observed were those due to systemic lupus erythematosus (30.2%), membranoproliferative glomerulonephritis (MPGN, 14.8%), and focal and segmental glomerulosclerosis (FSGS, 13.9%). Although mesangial-proliferative nephritis was observed in 9.5% of cases, IgA nephropathy was rare (0.9%). Examination of the year to year frequency showed that MPGN has tended to decrease in frequency with time whereas FSGS has been increasing. Although there is known to be a high frequency of infections in Peru, only 4.2% of the cases in the retrospective study were associated with infection. Furthermore, in the prospective study, only one case of hepatitis C and no cases of hepatitis B viral infection were detected, including in the 11 cases of MPGN observed., Conclusion: We conclude that the epidemiology of glomerular disease in Lima, Peru, is distinct from most areas of the world, but has similarities to certain regions in Africa, in that MPGN is common whereas IgA nephropathy appears to be rare. Further studies are necessary to elucidate the reasons why the patterns of glomerular disease are different from that observed in other parts of the world.

In orthostatic hypotensive patients renin is reported to increase in response to head-up tilt unless the lesion involves postganglionic sympathetic efferent nerves. The authors examined responses of plasma renin activity (PRA) to acute blood pressure reduction in 4 patients with orthostatic hypotension. When the coexistence of normal plasma norepinephrine (PNE) and normal or high-normal pressor response to alpha stimulant is considered to be a sign of preserved function of postganglionic fibers, 2 of the patients had sympathetic lesions mainly confined to central and/or preganglionic fibers. They were diagnosed as having multiple system atrophy (MSA). The other 2 were diagnosed as having idiopathic orthostatic hypotension with possible postganglionic lesions. Although 1 MSA patient showed an increase in PRA from 2.0 to 4.7 ng/mL/hr in response to the tilt, the other MSA patient showed no PRA response to the tilt. The head-up tilt did not provoke an apparent PRA response in patients with idiopathic orthostatic hypotension. The authors infused sodium nitroprusside (SNP) in the 3 patients whose PRA did not respond to the head-up tilt. The infusion decreased blood pressure by 40 mmHg or more, but PRA responses were inappropriately small or suppressed. In all cases, PNE did not respond at all to the head-up tilt and to the infusion of SNP. These findings suggest that possible preservation of postganglionic fibers does not necessarily indicate an intact responsiveness of PRA. The PRA profiling may not be an accurate predictor for the site of the fiber degeneration in orthostatic hypotension.