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Metals including Cu, Cd, Ni, Pb, Zn, Hg, Fe and Cr can be found in significant concentrations in acid mine drainage effluent from previous gold mining operations. Even at very low levels, heavy metals and their compounds are very toxic, carcinogenic, mutagenic and teratogenic. Acid mine drainage discharge must therefore be properly treated before disposal. In this study, iron removal from acid mine drainage effluent using immobilized green microalgae is explored. The impact of pH on iron metal concentrations was studied at multiple pH values between 2 and 12 using 0.1 M HCl or NaOH solutions. At pH 6, the optimal value, 82% and 90% of Fe (II) were removed from Ca-alginate beads and immobilized Desmodesmus sp., respectively. It was shown that Fe (II) ions were biosorbed by immobilized microalgae cells in a pseudo-second-order manner. This study demonstrated how immobilized green microalgae showed potential to remove iron from acid mine drainage effluent.

We test whether X-ray micro-computed tomography (microCT) imaging can be used as a tool for screening magnetite grains to improve the accuracy and precision of cosmogenic 3He exposure dating. We extracted detrital magnetite from a soil developed on a fanglomerate at Whitewater, California, which was offset by the Banning strand of the San Andreas Fault. This study shows that microCT screening can distinguish between inclusion-free magnetite and magnetite with fluid or common solid inclusions. Such inclusions can produce bulk 3He concentrations that are significantly in excess of the expected spallation production. We present Li concentrations, major and trace element analyses, and estimated magnetite (U–Th) / He cooling ages of samples in order to model the contribution from fissiogenic, nucleogenic, and cosmogenic thermal neutron production of 3He. We show that mineral inclusions in magnetite can produce 3He concentrations of up to 4 times that of the spallation component, leading to erroneous exposure ages. Therefore, grains with inclusions must be avoided in order to facilitate accurate and precise magnetite 3He exposure dating. Around 30 % of all grains were found to be without inclusions, as detectable by microCT, with the largest proportion of suitable grains in the grain size range of 400–800 µm. While grains with inclusions have 3He concentrations far in excess of the values expected from existing 10Be and 26Al data in quartz at the Whitewater site, magnetite grains without inclusions have concentrations close to the predicted depth profile. We measured 3He concentrations in aliquots without inclusions and corrected them for Li-produced components. By comparing these data to the known exposure age of 53.5 ± 2.2 ka, we calibrate a production rate for magnetite 3He at sea level and high latitude (SLHL) of 116 ± 13 at g−1 a−1. We suggest that this microCT screening approach can be used to improve the quality of cosmogenic 3He measurements of magnetite and other opaque mineral phases for exposure age and detrital studies.

Exothermic reversiblereactions are an industrially important classof processes, and many have complex kinetics associated with them.This article shows how experimentally measured variables such as residencetime, temperature, and conversion can be used to construct a three-dimensionalattainable region for a typical exothermic reversible reaction withouttaking into consideration the kinetics associated with the reaction.The experiments were conducted using an adiabatic batch reactor fittedwith a thermistor for temperature measurement. The article also showshow the two-dimensional conversion–temperature plot was obtainedfrom the three-dimensional residence time–temperature–conversionplot. The two-dimensional plot was then used to propose the optimalprocess configuration for the process where preheating, reaction,and mixing are allowed. Examination of the boundary of the two-dimensionalattainable region of the conversion–temperature plot providedthe optimal combination of reaction and mixing and thus the optimalreactor structure. The optimal reactor consists of the following reactorsin series: a CSTR, a PFR, a differential reactor, and finally anotherPFR. The article therefore concludes that, in principle, without knowledgeof the kinetics, measured variables such as residence times, temperaturesand conversions can be used to generate the attainable region ofthe process which can be used to propose the optimal process structurefor the process. This result can provide the process engineer witha benchmark for what can be obtained and also what the optimal reactorconfiguration should be for the process. [ABSTRACT FROM AUTHOR]

Wound healing is a complex dynamic biomechanical process as the body attempts to restore the integrity of traumatized or devitalized tissues. There are four stages of wound of healing that begins with hemostasis followed by inflammation, proliferation and finally weeks later wound remodeling. Full thickness wounds usually are covered with a dressing material after hemostasis, which allows for controlled hydration. We investigated the potential of a visco-liquid hemostat, polyhedral oligomeric silsesquioxane (POSS), for providing hemostasis and to maintain a microenvironment in the wound bed that would maintain moisture content and promote early re-epithelialization. We hypothesized that the hemostatic agent POSS if left in the wound bed would maintain a protective barrier and accelerate wound healing similar to using saline to irrigate the wound to keep the wound moist. We compared the early phase of wound repair (3-7 days) in a porcine full thickness wound model to evaluate the efficacy of the material. Biopsies were taken after 3 and 7 days to determine the acute response of the POSS hemostat or saline on inflammation, cell migration, concentrations of metalloproteinase (MMPs), and tissue inhibitors of metalloproteinase (TIMPs). Accelerated healing was observed in POSS treated wounds by changes in wound contraction, keratinocyte migration, and development of granulation tissue in comparison to saline treated wounds. Increased concentrations at day 3 of MMP-2, MMP-3, and in MMP-1 at day 7 in POSS treated wounds compared to saline coincide with keratinocyte migration observed in the tissue histology and changes in wound contraction. Tissue concentrations of TIMP-1 and TIMP-2 in POSS treated wounds appear to coordinate the sequence of MMP events in the healing tissue. Matrix metalloproteinase-13, a marker for tissue remodeling, was not upregulated in the early wound healing cascade in either POSS or saline treated wounds at 3 or 7 days. Overall, the data suggests POSS treatment contributed to enhanced early cell migration and wound closure compared to saline treatment.

Covalent organic frameworks (COFs) face limited processability challenges as photoelectrodes in photoelectrochemical water reduction. Herein, sub-10 nm benzothiazole-based colloidal conjugated reticular oligomers (CROs) are synthesized using an aqueous nanoreactor approach, and the end-capping molecular strategy to engineer electron-deficient units onto the periphery of a CRO nanocrystalline lattices (named CROs-Cg). This results in stable and processable "electronic inks" for flexible photoelectrodes. CRO-BtzTp-Cg and CRO-TtzTp-Cg expand the absorption spectrum into the infrared region and improve fluorescence lifetimes. Heterojunction device engineering is used to develop interlayer heterojunction and bulk heterojunction (BHJ) photoelectrodes with a hole transport layer, electron transport layer, and the main active layers, using a CROs/CROs-Cg or one-dimensional (1D) electron-donating polymer HP18 mixed solution via spinning coating. The ITO/CuI/CRO-TtzTp-Cg-HP18/SnO 2 /Pt photoelectrode shows a photocurrent of 94.9 µA cm ‒2 at 0.4 V versus reversible hydrogen electrode (RHE), which is 47.5 times higher than that of ITO/Bulk-TtzTp. Density functional theory calculations show reduced energy barriers for generating adsorbed H* intermediates and increased electron affinity in CROs-Cg. Mott-Schottky and charge density difference analyses indicate enhanced charge carrier densities and accelerated charge transfer kinetics in BHJ devices. This study lays the groundwork for large-scale production of COF nanomembranes and heterojunction structures, offering the potential for cost-effective, printable energy systems., (© 2024 The Authors. Advanced Science published by Wiley‐VCH GmbH.)

A series of crystalline, stable Metal (Metal = Zn, Cu, Ni, Co, Fe, and Mn)-Salen covalent organic framework (COF) EDA complex are prepared to continuously tune the band structure of Metal-Salen COF EDA , with the purpose of optimizing the free energy intermediate species during the hydrogen evolution reaction (HER) process. The conductive macromolecular poly(3,4-ethylenedioxythiophene) (PEDOT) is subsequently integrated into the one-dimensional (1D) channel arrays of Metal-Salen COF EDA to form heterostructure PEDOT@Metal-Salen COF EDA via the in situ solid-state polymerization method. Among the Metal-Salen COF EDA and PEDOT@Metal-Salen COF EDA complexes, the optimized PEDOT@Mn-Salen COF EDA displays prominent electrochemical activity with an overpotential of 150 mV and a Tafel slope of 43 mV dec -1 . The experimental results and density of states data show that the continuous energy band structure modulation in Metal-Salen COF EDA has the ability to make the metal d-orbital interact better with the s-orbital of H, which is conducive to electron transport in the HER process. Moreover, the calculated charge density difference indicates that the heterostructures composed of PEDOT and Metal-Salen COF EDA induce an intramolecular charge transfer and construct highly active interfacial sites., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

High-capacity Ni-rich layered oxides are considered as promising cathodes for lithium-ion batteries. However, the practical applications of LiNi 0.83 Co 0.07 Mn 0.1 O 2  (NCM83) cathode are challenged by continuous transition metal (TM) dissolution, microcracks and mixed arrangement of nickel and lithium sites, which are usually induced by deleterious cathode-electrolyte reactions. Herein, it is reported that those side reactions are limited by a reliable cathode electrolyte interface (CEI) layer formed by implanting a nonsacrificial nitrile additive. In this modified electrolyte, 1,3,6-Hexanetricarbonitrile (HTCN) plays a nonsacrificial role in modifying the composition, thickness, and formation mechanism of the CEI layers toward improved cycling stability. It is revealed that HTCN and 1,2-Bis(2-cyanoethoxy)ethane (DENE) are inclined to coordinate with the TM. HTCN can stably anchor on the NCM83 surface as a reliable CEI framework, in contrast, the prior decomposition of DENE additives will damage the CEI layer. As a result, the NCM83/graphite full cells with the LiPF6-EC/DEC-HTCN (BE-HTCN) electrolyte deliver a high capacity retention of 81.42% at 1 C after 300 cycles at a cutoff voltage of 4.5 V, whereas BE and BE-DENE electrolytes only deliver 64.01% and 60.05%. This nonsacrificial nitrile additive manipulation provides valuable guidance for developing aggressive high-capacity Ni-rich cathodes., (© 2022 Wiley-VCH GmbH.)

Several anthropogenic activities reduce the supply of freshwater to living organisms in all ecological systems, particularly the human population. Organic matter in derived wastewater can be converted into potential energy, such as biogas (methane), through microbial transformation during anaerobic digestion (AD). To address the current lack of data and values for wastewater generation in Sub-Saharan Africa, this review analyzes and estimates (at 50% and 90% conversion rates) the potential amount of wastewater-related sludge that can be generated from domestic freshwater withdrawals using the most recent update in 2017 from the World Bank repository and database on freshwater status in Sub-Saharan Africa. The Democratic Republic of the Congo (DRC) could potentially produce the highest estimate of biogas in Sub-Saharan Africa from domestic wastewater sludge of approximately 90 billion m 3 , which could be converted to 178 million MWh of electricity annually, based on this extrapolation at 50% conversion rates. Using same conversion rates estimates, at least nine other countries, including Guinea, Liberia, Nigeria, Sierra Leone, Angola, Cameroon, Central African Republic, Gabon, and Congo Republic, could potentially produce biogas in the range of 1-20 billion m 3 . These estimates show how much energy could be extracted from wastewater treatment plants in Sub-Saharan Africa. AD process to produce biogas and energy harvesting are essential supplementary operations for Sub-Saharan African wastewater treatment plants. This approach could potentially solve the problem of data scarcity because these values for Freshwater withdrawals are readily available in the database could be used for estimation and projections towards infrastructure development and energy production planning. The review also highlights the possibilities for energy generation from wastewater treatment facilities towards wastewater management, clean energy, water, and sanitation sustainability, demonstrating the interconnections and actualization of the various related UN Sustainable Development Goals., Competing Interests: The authors declare no conflict of interest., (© 2022 University of South Africa, Florida Campus. College of Science, Engineering and Technology, 28 Pioneer Ave, Florida Park.)

The effectiveness of the adsorption process is determined by the type of adsorbent used, but some adsorbents require a significant amount of processing to achieve the desired quality, and this has become a drawback economically and environmentally. This study focused on mitigating the issue of waste management and land pollution by using amarula waste biomass, which is a low-cost adsorbent that is obtained from the industrial waste by-product. The amarula shell (AmSh) waste was found to have a higher adsorption efficiency of 30 ± 3% compared to the amarula seed (AmSe) waste and the amarula fruit (AmWa) waste, which had 19 ± 5% and 9.5 ± 0.7% efficiency, respectively. It was found that the amarula waste biomass performed better at lower adsorption temperatures. The adsorption capacity was found to decrease with an increase in the quantity of the biomass. Kinetic models were applied to the experimental data. Thermodynamic parameters were also studied to determine the spontaneity of the adsorption process. The characteristics of both the fresh and used amarula waste biomass was analyzed by using Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy with Energy Dispersive Spectroscopy (FESEM-EDS), Brunauer-Emmett-Teller (BET) and Thermogravimetric Analysis (TGA). It was then concluded that cellulose and hemicellulose structures in amarula waste biomass played a major role in reducing the content of dibenzothiophene in model diesel fuel., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The main process of carbon dioxide (CO 2 ) photoreduction is that excited electrons are transported to surface active sites to reduce adsorbed CO 2 molecules. Obviously, electron transfer to the active site is one of the key steps in this process. However, current catalysts for CO 2 adsorption, activation, and electron reduction occur in different locations, which greatly reduce the efficiency of photocatalysis. Herein, through a spontaneous chemical redox approach, the plasmonic photocatalysts of Au-BiOCl-OV with enhanced interfacial interaction were fabricated for visible light CO 2 reduction through the simultaneous adsorption, activation and in situ reduction of CO 2 without a sacrificial agent. By loading gold (Au) on the oxygen vacancy (OV), Au and BiOCl-OV formed a direct and tight interface contact, whose fine structure was confirmed by SEM, TEM, EPR and XPS, which not only effectively boosts the light utilization efficiency and the light carrier separation ability, but also can simultaneously adsorb, activate and in situ reduce carbon dioxide for highly efficient visible light photocatalysis. Thanks to the synergistic influence of Au and OV, Au-BiOCl-OV exhibits excellent photocatalytic performance without sacrificial agent and outstanding stability with a high CO and CH 4 production yield, reaching 4.85 μmol g -1 h -1 , which were 2.8 times higher than C-Au-BiOCl-OV (obtained by traditional NaBH 4 reduction). This study proposes a new strategy for the production of high-performance collaborative catalysis in photocatalytic CO 2 reduction.

The COVID-19 pandemic has highlighted resource constraints in respiratory support. The oxygen transfer characteristics of a specific hollow fiber membrane dialyser was investigated with a view to repurposing the device as a low-cost, readily available blood oxygenator. Oxygen transfer in a low-flux hollow fiber dialyser with a polysulfone membrane was studied by passing first water and then blood through the dialyser in countercurrent to high-purity oxygen. Oxygen transfer rates of about 15% of the nominal 250 ml (STP)/min of a typical adult oxygen consumption rate were achieved for blood flow rates of 500 ml/min. Using two such dialysis devices in parallel could provide up to 30% of the nominal oxygen consumption. Specific hollow fiber dialysis devices operating with suitable pumps in a veno-venous access configuration could provide a cost-effective and readily available supplementation of respiratory support in the face of severe resource constraints., Competing Interests: Dr Claudia Do Vale's clinical practice includes managing patients at Fresenius Dialysis units. The authors declare that there are no other potential conflicts of interest., (Copyright © 2020 David M. Rubin et al.)

Biomass integrated gasification combined cycle (IGCC) is attracting increased interest because it can achieve high system energy efficiency (>50%), which is predicted to increase with the increase in the solar share in biomass IGCC. This study evaluated the potential of crop residues numerically for the co-production of power and bio-fertilizer using ASPEN Plus® simulation software. The results showed that the gas yield increases with increasing temperature and decreasing pressure while the yield of bio-fertilizer is dependent on the biomass composition. The biomass with a low ash content produces high bio-fertilizer at the designated gasification temperature. The IGCC configuration conserves more energy than a directly-fired biomass power plant. In addition, the solar-assisted IGCC attains a higher net electricity output per unit of crop residue feed and achieves net thermal efficiencies of around 53%. The use of such hybrid systems offer the potential to produce 0.55 MW of electricity per unit of solar-thermal energy at a relatively low cost. The ASPEN Plus model predicted that the solar biomass-based IGCC set up is more efficient in increasing the power generation capacity than any other conversion system. The results showed that a solar to electricity efficiency of approximately 55% is achievable with potential improvements. This work will contribute for the sustainable bioenergy production as the relationship between energy production and biomass supplies very important to ensure the food security and environmental sustainability., 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 © 2020 Elsevier Ltd. All rights reserved.)

The gentamicin drug product is a complex mixture of numerous components, many of which have not individually undergone safety and efficacy assessments. This is in contrast to the majority of medicines that require rigorous characterizations of trace impurities and are dosed as single components. In gentamicin, four components, known as gentamicin congeners C1, C1a, C2, and C2a, comprise the majority of the mixture. A liquid chromatography-mass spectroscopy analysis revealed that the relative abundances of each gentamicin congener in commercial formulations can vary up to 1.9-fold depending on the commercial source of the gentamicin. To determine if the gentamicin used for antibiotic susceptibility testing (AST) would be predictive of the microbiological activity of the product used to dose patients, the relative abundances of the four congeners contained on commercial AST disks were measured. It was found that the congener abundances on the commercial AST disks varied up to 4.1-fold. After purification of the four gentamicin congeners, similar potencies against bacterial strains lacking aminoglycoside-modifying enzymes (AMEs) were observed. However, the potency of the congeners against strains harboring a common AME differed up to 128-fold. Nephrotoxicity of the individual gentamicin congeners also differed significantly in cell-based and repeat-dose rat nephrotoxicity studies. Variations in the composition of commercial gentamicin products combined with toxicity differences between gentamicin congeners suggest that some gentamicin formulations may be more nephrotoxic. Our results also raise the concern that gentamicin susceptibility test results may not be predictive of patient outcomes and could lead to unexpected clinical treatment failures., (Copyright © 2020 American Society for Microbiology.)

New drugs with novel mechanisms of resistance are desperately needed to address both community and nosocomial infections due to Gram-negative bacteria. One such potential target is LpxC, an essential enzyme that catalyzes the first committed step of lipid A biosynthesis. Achaogen conducted an extensive research campaign to discover novel LpxC inhibitors with activity against Pseudomonas aeruginosa We report here the in vitro antibacterial activity and pharmacodynamics of ACHN-975, the only molecule from these efforts and the first ever LpxC inhibitor to be evaluated in phase 1 clinical trials. In addition, we describe the profiles of three additional LpxC inhibitors that were identified as potential lead molecules. These efforts did not produce an additional development candidate with a sufficiently large therapeutic window and the program was subsequently terminated., (Copyright © 2019 American Society for Microbiology.)

Background: Prehospital ECG-based cardiac catheterization laboratory (CCL) activation for ST-segment-elevation myocardial infarction reduces door-to-balloon times, but CCL cancellations (CCL X ) remain a challenging problem. We examined the reasons for CCL X , clinical characteristics, and outcomes of patients presenting as ST-segment-elevation myocardial infarction activations who receive emergent coronary angiography (EA) compared with CCL X ., Methods and Results: We reviewed all consecutive CCL activations between January 1, 2012, and December 31, 2014 (n=1332). Data were analyzed comparing 2 groups stratified as EA (n=466) versus CCL X (n=866; 65%). Reasons for CCL X included bundle branch block (21%), poor-quality prehospital ECG (18%), non-ST-segment-elevation myocardial infarction ST changes (18%), repolarization abnormality (13%), and arrhythmia (8%). A multivariate logistic regression model using age, peak troponin, and initial ECG findings had a high discriminatory value for determining EA versus CCL X (C statistic, 0.985). CCL X subjects were older and more likely to be women, have prior coronary artery bypass grafting, or a paced rhythm ( P<0.0001 for all). All-cause mortality did not differ between groups at 1 year or during the study period (mean follow-up, 2.186±1.167 years; 15.8% EA versus 16.2% CCL X ; P=0.9377). Cardiac death was higher in the EA group (11.8% versus 3.0%; P<0.0001). After adjusting for clinical variables associated with survival, CCL X was associated with an increased risk for all-cause mortality during the study period (hazard ratio, 1.82; 95% CI, 1.28-2.59; P=0.0009)., Conclusions: In this study, prehospital ECG without overreading or transmission lead to frequent CCL X . CCL X subjects differ with regard to age, sex, risk factors, and comorbidities. However, CCL X patients represent a high-risk population, with frequently positive cardiac enzymes and similar short- and long-term mortality compared with EA. Further studies are needed to determine how quality improvement initiatives can lower the rates of CCL X and influence clinical outcomes.

The ability of electronic structure methods (11 density functionals, HF, and MP2 calculations; two basis sets and two solvation models) to accurately calculate the 19 F chemical shifts of 31 structures of fluorinated amino acids and analogues with known experimental 19 F NMR spectra has been evaluated. For this task, BHandHLYP, ωB97X, and Hartree-Fock with scaling factors (provided within) are most accurate. Additionally, the accuracy of methods to calculate relative changes in fluorine shielding across 23 sets of structural variants, such as zwitterionic amino acids versus side chains only, was also determined. This latter criterion may be a better indicator of reliable methods for the ultimate goal of assigning and interpreting chemical shifts of fluorinated amino acids in proteins. It was found that MP2 and M062X calculations most accurately assess changes in shielding among analogues. These results serve as a guide for computational developments to calculate 19 F chemical shifts in biomolecular environments. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Aims: End-stage renal disease (ESRD) is associated with high morbidity and mortality. A prior study showed that many Canadian patients regretted their decision to start dialysis. We sought to determine if US patients also regretted dialysis., Materials and Methods: We surveyed hemodialysis patients within 55 miles of Rochester, MN, with a 25-question survey about their perceptions of their health, preparedness for dialysis, advance care planning, and regrets about starting dialysis. Surveys were administered in person at the patients' usual dialysis session from July 1 through December 1, 2014; responses were captured electronically., Results: Of the 198 eligible patients, 128 participated (70% men); 80% received dialysis for more than 1 year; 38% reported their health and 58% described their quality of life as "good" or "very good"; 51% had started dialysis in the hospital; and 68% agreed they were prepared for what to expect. Only 35% of patients reported being offered supportive care without dialysis. Most patients (82%) recalled a discussion about prognosis. Only 43% completed an advance directive, but 72% thought it was at least "very important" to plan for the end of life. Nine (7%) reported regretting the decision to start dialysis., Conclusions: Most of our patients were optimistic about their health and prognosis. Few regretted the decision to start dialysis.
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Background: Urine production in the kidney is generally thought to be an energy-intensive process requiring large amounts of metabolic activity to power active transport mechanisms. This study uses a thermodynamic analysis to evaluate the minimum work requirements for urine production in the human kidney and provide a new perspective on the energy costs of urine production. In this study, black-box models are used to compare the Gibbs energy inflow and outflow of the overall kidney and physiologically-based subsections in the kidney, to calculate the work of separation for urine production., Results: The results describe the work done during urine production broadly and for specific scenarios. Firstly, it shows glomerular filtration in both kidneys requires work to be done at a rate of 5 mW under typical conditions in the kidney. Thereafter, less than 54 mW is sufficient to concentrate the filtrate into urine, even in the extreme cases considered. We have also related separation work in the kidney with the excretion rates of individual substances, including sodium, potassium, urea and water. Lastly, the thermodynamic calculations indicate that plasma dilution significantly reduces the energy cost of separating urine from blood., Conclusions: A comparison of these thermodynamic results with physiological reference points, elucidates how various factors affect the energy cost of the process. Surprisingly little energy is required to produce human urine, seeing that double the amount of work can theoretically be done with all the energy provided through pressure drop of blood flow through the kidneys, while the metabolic energy consumption of the kidneys could possibly drive almost one hundred times more separation work. Nonetheless, the model's outputs, which are summarised graphically, show the separation work's nuances, which can be further analysed in the context of more empirical evidence.

Background and Objectives: ESRD requiring dialysis is associated with increased morbidity and mortality rates, including increased rates of cognitive impairment, compared with the general population. About one quarter of patients receiving dialysis choose to discontinue dialysis at the end of life. Advance directives are intended to give providers and surrogates instruction on managing medical decision making, including end of life situations. The prevalence of advance directives is low among patients receiving dialysis. Little is known about the contents of advance directives among these patients with advance directives., Design, Setting, Participants, & Measurements: We retrospectively reviewed the medical records of all patients receiving maintenance in-center hemodialysis at a tertiary academic medical center between January 1, 2007 and January 1, 2012. We collected demographic data, the prevalence of advance directives, and a content analysis of these advance directives. We specifically examined the advance directives for instructions on management of interventions at end of life, including dialysis., Results: Among 808 patients (mean age of 68.6 years old; men =61.2%), 49% had advance directives, of which only 10.6% mentioned dialysis and only 3% specifically addressed dialysis management at end of life. Patients who had advance directives were more likely to be older (74.5 versus 65.4 years old; P<0.001) and have died during the study period (64.4% versus 46.6%; P<0.001) than patients who did not have advance directives. Notably, for patients receiving dialysis who had advance directives, more of the advance directives addressed cardiopulmonary resuscitation (44.2%), mechanical ventilation (37.1%), artificial nutrition and hydration (34.3%), and pain management (43.4%) than dialysis (10.6%)., Conclusions: Although one-half of the patients receiving dialysis in our study had advance directives, end of life management of dialysis was rarely addressed. Future research should focus on improving discernment and documentation of end of life values, goals, and preferences, such as dialysis-specific advance directives, among these patients., (Copyright © 2016 by the American Society of Nephrology.)

Various models have been proposed to explain the urine concentrating mechanism in mammals, however uncertainty remains regarding the origin of the energy required for the production of concentrated urine. We propose a novel mechanism for concentrating urine. We postulate that the energy for the concentrating process is derived from the osmotic potentials generated by the separation of afferent blood into protein-rich efferent blood and protein-deplete filtrate. These two streams run in mutual juxtaposition along the length of the nephron and are thus suitably arranged to provide the osmotic potential to concentrate the urine. The proposed model is able to qualitatively explain the production of various urine concentrations under different clinical conditions. An approach to testing the feasibility of the hypothesis is proposed., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Understanding pediatric sudden cardiac death (SCD) may inform age-specific prevention strategies., Objective: To characterize potential underlying causes of SCD in children and adolescents, Methods: We performed a retrospective population-based study in Ontario, Canada, of all SCD cases in a 5-year period (2005-2009) involving persons aged 1-19 years identified from the comprehensive database of the Office of the Chief Coroner. Of 1204 coroner's cases, 351 potential SCD cases were reviewed., Results: Of 116 cases of adjudicated SCD, there was no identifiable cause of death in 60 (52%). The majority were males (66%), and median age was 12.7 years. The incidence of SCD was greatest between 1 and 2 years (3.14 per 100,000 person-years), decreased, and then increased to 1.01 per 100,000 person-years (15-19 years). Autopsy findings were normal in 29 of 35 (83%) of children younger than 5 years and were more likely to be abnormal in those 10 years and older (odds ratio 9.0; 95% confidence interval 3.3-24.9). In 9%, the pathology findings may be of uncertain significance. Most events occurred in the home (68%). Activity level at the time of the event was associated with both age group (χ(2) = 34.9; P < .001) and autopsy findings (χ(2) = 28.9; P < .001). Events during moderate or vigorous activity were more common in those older than 10 years 16 of 66 (24%), and the majority had abnormal autopsy findings 13 of 18 (72%)., Discussion: Death in the very young is often caused by presumed primary arrhythmia syndromes, and death during exertion is typically seen in those with structural heart disease., Conclusion: These differences should inform age-specific diagnostic and prevention strategies., (© 2014 Heart Rhythm Society Published by Heart Rhythm Society All rights reserved.)

Background: Understanding sudden cardiac death in the young may inform prevention strategies., Objective: To determine the scope and nature of sudden death in a geographically defined population., Methods: We performed a retrospective population-based cohort study in Ontario, Canada, of all sudden cardiac death cases involving persons aged 2-40 years identified from the 2008 comprehensive Coroner database. Of 1741 Coroner's cases, 376 were considered potential sudden cardiac death cases and underwent review., Results: There were 174 cases of adjudicated sudden cardiac death from a population of 6,602,680 persons aged 2-40 years. Structural heart disease was present in 126 cases (72%), 78% of which was unrecognized. There was no identifiable cause of death in 48 cases (28%), representing primary arrhythmia syndromes. The majority of decedents were men (76%) over the age of 18 (90%). The overall incidence of sudden cardiac death increased with age from 0.7/100,000 (2-18 years) to 2.4/100,000 (19-29 years) to 5.3/100,000 (30-40 years) person-years. Persons experiencing sudden cardiac death before age 30 were more likely to have a primary arrhythmia syndrome (odds ratio 2.97; P<.001). The majority of events occurred in the home (72%); 33% of the events in children/adolescents and 9% of the events in adults occurred during reported moderate or vigorous exercise (P = .002). There were no pediatric deaths during organized competitive sports., Conclusions: The incidence of sudden cardiac death increases with age, typically occurring in a man at rest in the home with unrecognized underlying heart disease or a primary arrhythmia syndrome. Prevention strategies should consider targeting identification of unrecognized structural heart disease and primary arrhythmia syndromes., (Copyright © 2013 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: The impact of the prescription opioid public health crisis has been illustrated by the dramatic increase in opioid-related deaths in North America. We aimed to identify patterns and characteristics amongst opioid-users whose cause of death was related to opioid toxicity., Methods: This was a population-based study of Ontarians between the years 2006 and 2008. All drug-related deaths which occurred during this time frame were reviewed at the Office of the Chief Coroner of Ontario, and opioid-related deaths were identified. Medical, toxicology, pathology, and police reports were comprehensively reviewed. Narratives, semi-quantitative, and quantitative variables were extracted, tabulated, and analyzed., Results: Out of 2330 drug-related deaths in Ontario, 58% were attributed either in whole or in part, to opioids (n = 1359). Oxycodone was involved in approximately one-third of all opioid-related deaths. At least 7% of the entire cohort used opioids that were prescribed for friends and/or family, 19% inappropriately self-administered opioids (injection, inhalation, chewed patch), 3% were recently released from jail, and 5% had been switched from one opioid to another near the time of death. Accidental deaths were significantly associated with personal history of substance abuse, enrollment in methadone maintenance programs, cirrhosis, hepatitis, and cocaine use. Suicides were significantly associated with mental illness, previous suicide attempts, chronic pain, and a history of cancer., Significance/conclusion: These results identify novel, susceptible groups of opioid-users whose cause of death was related to opioids in Ontario and provide the first evidence to assist in quantifying the contribution of opioid misuse and diversion amongst opioid-related mortality in Canada. Multifaceted prevention strategies need to be developed based on subpopulations of opioid users.

The critical issues in the development of diagnostics, which need to work robust and reliable under quasi-steady state conditions for the discharge durations of 30 min and which cannot be maintained throughout the one week duration of each operation phase of the Wendelstein 7-X stellarator, are being discussed.

The status of the diagnostic developments for the quasistationary operable stellarator Wendelstein 7-X (maximum pulse length of 30 min at 10 MW ECRH heating at 140 GHz) will be reported on. Significant emphasis is being given to the issue of ECRH stray radiation shielding of in-vessel diagnostic components, which will be critical at high density operation requiring O2 and OXB heating.

Fatal opioid toxicity occurred in a developmentally delayed child aged 5 years 9 months who was inadvertently administered high doses of hydrocodone for a respiratory tract infection. The concentration of hydrocodone in postmortem blood was in the range associated with fatality; however, hydromorphone, a major metabolite catalyzed by cytochrome P450 2D6 (CYP2D6), was not detected when using mass spectrometry. Genetic analysis revealed that the child had a reduced capability to metabolize the drug via the CYP2D6 pathway (CYP2D6*2A/*41). Coadministration of clarithromycin (a potent cytochrome P450 3A4 inhibitor) for an ear infection and valproic acid for seizures since birth further prevented drug elimination from the body. This case highlights the interplay between pharmacogenetic factors, drug-drug interactions, and dose-related toxicity in a child.

Objectives: The objective was to determine if 9-1-1 paramedics trained in ultrasound (US) could adequately perform and interpret the Focused Assessment Sonography in Trauma (FAST) and the abdominal aortic (AA) exams in the prehospital care environment., Methods: Paramedics at two emergency medical services (EMS) agencies received a 6-hour training program in US with ongoing refresher education. Paramedics collected US in the field using a prospective convenience methodology. All US were performed in the ambulance without scene delay. US exams were reviewed in a blinded fashion by an emergency sonographer physician overreader (PO)., Results: A total of 104 patients had an US performed between January 1, 2008, and January 1, 2009. Twenty AA exams were performed and all were interpreted as negative by the paramedics and the PO. Paramedics were unable to obtain adequate images in 7.7% (8/104) of the patients. Eighty-four patients had the FAST exam performed. Six exams (6/84, 7.1%) were read as positive for free intraperitoneal/pericardial fluid by both the paramedics and the PO. FAST and AA US exam interpretation by the paramedics had a 100% proportion of agreement with the PO., Conclusions: This pilot study shows that with close supervision, paramedics can adequately obtain and interpret prehospital FAST and AA US images under protocol. These results support a growing body of literature that indicates US may be feasible and useful in the prehospital setting., ((c) 2010 by the Society for Academic Emergency Medicine.)

Objectives: To follow blood pressure change over time in participants who had participated in a 1- year chronic disease management program focused on blood pressure reduction. The expectation was that blood pressure would return back to the baseline once the study was completed., Study Design: Prospective, single-arm observational study., Methods: Study participants were Status Indians living on-reserve with type 2 diabetes and persistent hypertension who had participated in the DREAM3 study. Blood pressure was measured with the BpTRU automated device every 6 months for 2 years. The primary endpoint was the change in systolic blood pressure over the follow-up period., Results: Sixty of the original 96 participants agreed to participate in the follow-up. Mean blood pressure at the beginning of the follow-up was 130/76 (SD 18/12) mmHg. Mean blood pressure at the end of the follow-up period was 132/76 (17/9 SD) mmHg. Target blood pressure (<130/80 mmHg) was present in 53%. The 99% confidence limit around change of blood pressure over the 24 months of follow-up was +/-4.7 mmHg., Conclusions: Contrary to expectations, the participants maintained their blood pressure control and did not revert to baseline levels. Community awareness and engagement resulting from the chronic disease management program led to a sustainable improvement in the health parameters of the participants and the community that lasted beyond the duration of the 1-year DREAM3 project.