Modeling the fate of viruses in aquifers: Multi-kinetics reactive transport, risk assessment, and governing parameters.

The transport of viruses in groundwater is a complex process controlled by both hydrodynamic and reaction parameters. Characterizing the transport of viruses in groundwater is of crucial importance for investigating health risks associated with groundwater consumption from private individual or residential pumping wells. Setback distances between septic systems, which are the source of viruses, and pumping wells must be designed to offer sufficient groundwater travel times to allow the viral load to degrade sufficiently to be acceptable for community health needs. This study consists of developing numerical simulations for the reactive transport of viruses in the subsurface. These simulations are validated using published results of laboratory and field experiments on virus transport in the subsurface and applying previously developed analytical solutions. The numerical model is then exploited to investigate the sensitivity of the fate of viruses in saturated porous media to hydraulic parameters and the coefficients of kinetic reactions. This sensitivity analysis provides valuable insights into the prevailing factors governing health risks caused by contaminated water in private wells in rural residential contexts. The simulations of virus transport are converted into health risk predictions through dose-response relationships. Risk predictions for a wide range of input parameters are compared with the international regulatory health risk target of a maximum of 10-4 infections/person/year and a 30 m setback distance to identify critical subsurface contexts that should be the focus of regulators.

Removal of nickel from neutral mine drainage using peat-calcite, compost, and wood ash in column reactors.

The effectiveness of compost, peat-calcite, and wood ash to remove Ni from a circum-neutral-contaminated mine water was tested in continuous flow experiments. Materials were compared in 4.8-L columns at hydraulic residence times (HRT) of ∼ 16.5 h over the course of 2.5-4 months. During this period, all columns successfully treated over 400 L of synthetic contaminated neutral drainage (4.05 mg/L Ni), mainly through sorption processes. Mid-column results (HRT ∼ 9 h) indicated that wood ash was the most effective material for Ni removal, and chemical extractions revealed that retained Ni was less mobile in this spent material. The pH-increasing properties of wood ash played a major role in this material's performance, but a pH correction would be required in the initial stages of full-scale treatment to maintain the effluent within regulatory limits (6-9.5). Scaled to full-sized, mid-column results indicated that treatment cell sizes, designed for the 1-year treatment of a high discharge (10 m3/h)-contaminated effluent (4.05 mg/L Ni), would be the smallest with wood ash (< 500 m3), followed by compost (600 ± 140 m3) and peat-calcite (720 ± 50 m3).

Analgesic gas for rehabilitation of frozen shoulder: Protocol for a randomized controlled trial.

BACKGROUND: There is little evidence regarding the best way to treat adhesive capsulitis. Physical therapy can reduce pain and improve function and range of motion. However, we lack clear indications on the regimen, techniques or intensity of physical therapy to achieve better results. Intensive physical therapy seems to be confined to the later stages of adhesive capsulitis (chronic stage) given that rehabilitation-induced pain could worsen the outcomes. Here we describe a protocol for a study comparing the efficacy of a standardized program of intensive mobilization under analgesic gas to a similar program under placebo gas and questioning the impact of pain. METHOD/DESIGN: A randomized, double-blind, multicenter study - the MEOPA Trial - was designed to include adults with strictly defined clinical adhesive capsulitis for a 14-day intensive physical rehabilitation program under an equimolar mixture of oxygen and nitrous oxide or sham gas administration. Efficacy will be assessed by the Constant-Murley score. Data for secondary criteria including pain, disability, quality of life and perceived efficacy by the patient or physiotherapist will be collected over 6 months. DISCUSSION: This randomized controlled trial has been designed to test the effectiveness of intensive physical therapy under a simple and safe analgesic method. This study will also address the effect of pain during rehabilitation in adhesive capsulitis. Furthermore, results from the 6-month multidimensional follow-up of painful mobilization for this condition could be extrapolated to other musculoskeletal conditions. TRIAL REGISTRATION: ClinicalTrials.gov No. NCT01087229.

Determination of point of zero charge of natural organic materials.

This study evaluates different methods to determine points of zero charge (PZCs) on five organic materials, namely maple sawdust, wood ash, peat moss, compost, and brown algae, used for the passive treatment of contaminated neutral drainage effluents. The PZC provides important information about metal sorption mechanisms. Three methods were used: (1) the salt addition method, measuring the PZC; (2) the zeta potential method, measuring the isoelectric point (IEP); (3) the ion adsorption method, measuring the point of zero net charge (PZNC). Natural kaolinite and synthetic goethite were also tested with both the salt addition and the ion adsorption methods in order to validate experimental protocols. Results obtained from the salt addition method in 0.05 M NaNO3 were the following: 4.72 ± 0.06 (maple sawdust), 9.50 ± 0.07 (wood ash), 3.42 ± 0.03 (peat moss), 7.68 ± 0.01 (green compost), and 6.06 ± 0.11 (brown algae). Both the ion adsorption and the zeta potential methods failed to give points of zero charge for these substrates. The PZC of kaolinite (3.01 ± 0.03) was similar to the PZNC (2.9-3.4) and fell within the range of values reported in the literature (2.7-4.1). As for the goethite, the PZC (10.9 ± 0.05) was slightly higher than the PZNC (9.0-9.4). The salt addition method has been found appropriate and convenient to determine the PZC of natural organic substrates.

Prevalence of early dementia after first-ever stroke: a 24-year population-based study.

BACKGROUND AND PURPOSE: No data about temporal change in the prevalence of poststroke dementia are available. We aimed to evaluate trends in the prevalence of early poststroke dementia. METHODS: From 1985 to 2008, overall first-ever strokes occurring within the population of the city of Dijon, France (150 000 inhabitants) were recorded. The presence of dementia was diagnosed during the first month after stroke, according to Diagnostic and Statistical Manual of Mental Disorders, Third and Fourth Editions criteria. Time trends were analyzed according to 4 periods: 1985 to 1990, 1991 to 1996, 1997 to 2002, and 2003 to 2008. Logistic regression was used for nonmultivariate analyses. RESULTS: Over the 24 years, 3948 first-ever strokes were recorded. Among patients with stroke, 3201 (81%) were testable of whom 653 (20.4%) had poststroke dementia (337 women and 316 men). The prevalence of nontestable (mostly due to death) patients declined from 28.0% to 10.2% (P<0.0001). Multivariate analysis revealed significant temporal changes in the prevalence of poststroke dementia; prevalence in the second and fourth periods was, respectively, almost half and twice that in the first period. The prevalence of poststroke dementia associated with lacunar stroke was 7 times higher than that in intracerebral hemorrhage but declined over time as did prestroke antihypertensive medication. Age, several vascular risk factors, hemiplegia, and prestroke antiplatelet agents were associated with an increased prevalence of poststroke dementia. CONCLUSIONS: This study covering a period of 24 years highlights temporal changes in the prevalence of early dementia after first-ever stroke. These changes may be explained by concomitant determinants of survival and incidence such as stroke care management or prestroke medication.

RT-PCR for mammaglobin genes, MGB1 and MGB2, identifies breast cancer micrometastases in sentinel lymph nodes.

In the present study, we examined the expression of the mammaglobin genes, MGB1 and MGB2, in the sentinel lymph nodes (SLNs) of patients with breast cancer and compared our results with the histologic status of the same SLNs. Compared with immunohistochemical staining for cytokeratin 8, which detected metastases in 17 of 42 patients, reverse transcription-polymerase chain reaction (RT-PCR) for MGB1 or MGB2 genes was positive in 22 patients. The concordance between the expression of any mammaglobin and histologic status was 79% (33/42), with a sensitivity of 88% and specificity of 72%. The detection of patients with metastases was more sensitive when testing for both MGB1 and MGB2 (P < .0001) rather than MGB2 (P < .0005) or MGB1 (P < .05) alone. The increased detection rate relative to histologic examination suggests that using RT-PCR for the mammaglobin genes might identify patients at higher risk compared with patients with negative RT-PCR results.

Post-Traumatic Pseudoaneurysm of the Left Sinus of Valsalva Revealed by an Acute Coronary Compression: An Echocardiographic Case Report.

A 69-year-old woman presented with chest pain and electrocardiographic evidence of subacute anterior ischaemia. Transthoracic and transesophageal echocardiography allowed correct diagnosis of a posttraumatic pseudoaneurysm of the left sinus of Valsalva. The large pseudoaneurysm caused compression of the left main coronary artery and was successfully treated by aortic root replacement, left main coronary artery ligation, and arterial bypass.