Vicia faba Crop Residues for Sustainable Electricity Generation Using a Sludge-based Microbial Fuel Cell

Microbial fuel cells (MFC) simultaneously degrade organic substrates and generate electricity in a sustainable and eco-friendly way. Here, we built a 4-unit MFC and studied the efficiency of MFC at different conditions, including pH, substrate concentration of Vicia faba agricultural wastes with exoelectrogenic bacteria P. aeruginosa. The exoelectrogenic bacteria were obtained from industrial effluents and used to inoculate the MFCs. The optimized conditions in terms of yielding maximum potential of 802 mV, yielding maximum power density of 283 mW m–2 were reported at a substrate concentration of 6 g L–1 of V. faba waste and pH of 5.5, corresponding to a current density 1255.93 mA m–2. Using exoelectrogenic bacteria from industrial effluents and agricultural wastes resulted in efficient MFC. Thus, the developed MFCs using V. faba agricultural wastes can be used in rural areas that have limited access to electricity, by reusing agricultural wastes and concomitant electricity generation. This work is licensed under a Creative Commons Attribution 4.0 International License

Adsorptive stripping voltammetric determination of trace level Ricin in castor seeds using a boron-doped diamond electrode.

Ricin, (Ricinus communis agglutinin, RCA) is one of the most poisonous of naturally occurring substances and has great potential for bioterrorism because no antidote exists. Fast detection at low concentrations is a challenge, and vital to the development of proper countermeasures. In this study, a square wave adsorptive stripping voltammetric (SWAdSV) method for determining RCA using a cathodically polarized boron-doped diamond (BDD) electrode is presented. An irreversible electrochemical RCA oxidation peak was identified on the BDD electrode by different voltammetric techniques using both direct and adsorptive stripping modes. An adsorption-controlled (slope log Ip vs log v of 0.80) pHdependent process was observed. For values of 1.0pH 9.0, the numbers of protons and electrons associated with the oxidation reaction were estimated (ca. 1.0) by differential pulse voltammetry. The RCA oxidation step may correspond to the oxidation of tryptophan amino acid residues, and occurs in a complex mechanism. The excellent analytical performance of the cathodically polarized BDD electrode in combination with the stripping mode ramp was verified with RCA by using a short deposition time in an open circuit potential (120 s). Under optimized analysis conditions, a linear response in the range of (3.3?94.0)3109 mol L1 (r2=0.9944) and a limit of detection of 6.231010 mol L1 were estimated. This LOD is lower than several methods found in the literature. For example, it is 168 times lower than that obtained by using square wave voltammetric with a glassy carbon electrode. Moreover, an even lower LOD might be achieved by using the SWAdSV method with a higher pre-concentration time. In addition, trace levels of RCA were successfully determined in different castor seed cultivars with an overall average recovery from 99.2 1.6% for the three different RCA-A concentration levels. The high accuracy of the analytical data highlights the use of the proposed method for determining RCA in other samples

Outstanding performance of the microwave-made MMO-Ti/RuO2IrO2 anode on the removal of antimicrobial activity of Penicillin G by photoelectrolysis

This paper studies the applicability of a novel microwave-prepared mixed metal oxide (MMO-Ti/RuO2IrO2) anode in the electrolysis and photo-electrolysis of synthetic urine intensified with Penicillin G. Results are compared with those obtained using boron-doped diamond (BDD) as the anode. In general, electrolysis with both anodes are effective in terms of penicillin removal, and the combination with UV radiation shows a clear synergistic effect on the degradation of Penicillin G: 420% and 355% using MMO and BDD, respectively. The outstanding performance of the MMO-Ti/RuO2IrO2 anode is demonstrated by the decrease in toxicity and the reduction of the antibiotic effect on the urine observed during photo-electrolysis. Notably, photo-electrolysis using the MMO-Ti/RuO2IrO2 anode generates solutions with almost zero residual toxicity and without antibiotic effect, with lower specific energy consumption than using BDD anode. The remarkable performance of the microwaves-prepared MMO-Ti/RuO2IrO2 coatings makes them very promising for being used in the electrochemical treatment of sanitary wastes.Este artículo estudia la aplicabilidad de un novedoso ánodo de óxido metálico mixto (MMO-Ti/RuO 2 IrO 2 ) preparado con microondas en la electrólisis y fotoelectrólisis de orina sintética intensificada con penicilina G. Los resultados se comparan con los obtenidos usando diamante (BDD) como ánodo. En general, la electrólisis con ambos ánodos es efectiva en términos de eliminación de penicilina, y la combinación con radiación UV muestra un claro efecto sinérgico en la degradación de Penicilina G: 420% y 355% usando MMO y BDD, respectivamente. El excelente rendimiento del MMO-Ti/RuO 2 IrO 2ánodo se demuestra por la disminución de la toxicidad y la reducción del efecto antibiótico en la orina observado durante la fotoelectrólisis. En particular, la fotoelectrólisis utilizando el ánodo MMO-Ti/RuO 2 IrO 2 genera soluciones con una toxicidad residual casi nula y sin efecto antibiótico, con un consumo de energía específico menor que utilizando el ánodo BDD. El notable rendimiento de los recubrimientos MMO-Ti/RuO 2 IrO 2 preparados con microondas los hace muy prometedores para su uso en el tratamiento electroquímico de desechos sanitarios

Platinum: A key element in electrode composition for reversible chloralkaline electrochemical cells

In this work, the performance of a reversible electrochemical cell using three different electrodes (Ti/Ru0.5Ir0.5O2, Ti/Ru0.3Ti0.7O2, and Ti/Ru0.3Ti0.6O2Pt0.1) is evaluated and compared for the oxidation of chlorides and reduction of chlorine. Results indicate that this technology is successful and that its efficiency depends significantly on the composition of the electrode in charge of the chlorine electrochemistry. Operating at 0.5 V allows us to obtain near 7 mA cm−2 and power efficiencies around 120 Wh mmol−1 hydrogen supplied. In electrolytic mode, efficiencies around 4 mol Cl2 mWh−1 can be obtained. The best performance is shown by the Ti/Ru0.3Ti0.6O2Pt0.1 electrode resulting from its roughest morphology and the presence of Pt. In shifting from electrolyzer to fuel cell mode, the current produced is rapidly stabilized for Ti/Ru0.3Ti0.6O2Pt0.1 and Ti/Ru0.5Ir0.5O2 electrodes. However, the electrode Ti/Ru0.5Ir0.5O2 showed a progressive change, which suggests a change in its composition that negatively affects the system.En este trabajo se evalúa y compara el desempeño de una celda electroquímica reversible utilizando tres electrodos diferentes (Ti/Ru 0.5 Ir 0.5 O 2 , Ti/Ru 0.3 Ti 0.7 O 2 , y Ti/Ru 0.3 Ti 0.6 O 2 Pt 0.1 ). para la oxidación de cloruros y reducción de cloro. Los resultados indican que esta tecnología es exitosa y que su eficiencia depende significativamente de la composición del electrodo a cargo de la electroquímica del cloro . Operando a 0,5 V nos permite obtener cerca de 7 mA cm −2y eficiencias energéticas de alrededor de 120 Wh mmol- 1 de hidrógeno suministrado. En modo electrolítico se pueden obtener eficiencias en torno a 4 mol Cl 2 mWh− 1 . El electrodo Ti/Ru 0.3 Ti 0.6 O 2 Pt 0.1 presenta el mejor comportamiento debido a su morfología más rugosa ya la presencia de Pt. Al pasar del modo electrolizador al modo de pila de combustible, la corriente producida se estabiliza rápidamente para los electrodos Ti/Ru 0,3 Ti 0,6 O 2 Pt 0,1 y Ti/Ru 0,5 Ir 0,5 O 2 . Sin embargo, el electrodo Ti/Ru0.5 Ir 0.5 O 2 mostró un cambio progresivo, lo que sugiere un cambio en su composición que afecta negativamente al sistema

Electrochemical systems equipped with 2D and 3D microwave-made anodes for the highly efficient degradation of antibiotics in urine

This work focuses on the importance of choosing a suitable electrochemical cell to remove antibiotics from urines. For this purpose, we investigate the use of two electrochemical cells for electrolysis and photo-electrolysis of urine polluted with a mixture of Penicillin G, Meropenem, and Chloramphenicol. The two reactors studied were a conventional flow pass electrochemical cell (E-cell) and a microfluidic flow-through reactor (MF-Reactor). Both reactors are equipped with a mixed metal oxide anode (MMO-RuO2IrO2) produced by hybrid heating using microwaves. The MMO coating was deposited on a Ti plate for the E-cell (2-D electrode) and on a Ti foam for the MF-Reactor (3-D electrode). Results demonstrate that the MF-Reactor stands out to reduce two important factors in electrochemical oxidation, the ohmic resistance associated with the microfluidic concept and the mass transfer limitations associated with the flow-through configuration. Moreover, it allows operating at a lower effective current density because of its larger active anodic surface area. Photo-electrolysis results in faster removal of all antibiotics studied in the MF-Reactor and E-cell, compared to the single electrolysis, thereby highlighting the significance of UV light-mediated electrochemical oxidation processes. This work highlights that despite the large number of papers focused on the selection of suitable electrodes for the electrochemical treatment of different types of wastes, the choice of the electrochemical cell can be even more important than the selection of those electrode materials, and it demonstrates that even using the same coating as the anode, highly different outcomes can be reached.Este trabajo se centra en la importancia de elegir una celda electroquímica adecuada para eliminar los antibióticos de las orinas. Para ello, investigamos el uso de dos celdas electroquímicas para la electrólisis y fotoelectrólisis de orina contaminada con una mezcla de Penicilina G, Meropenem y Cloranfenicol. Los dos reactores estudiados fueron una celda electroquímica de paso de flujo convencional (celda E) y un reactor de flujo continuo microfluídico (reactor MF). Ambos reactores están equipados con un ánodo de óxido metálico mixto (MMO-RuO 2 IrO 2) producido por calentamiento híbrido usando microondas. El recubrimiento de MMO se depositó en una placa de Ti para la celda E (electrodo 2D) y en una espuma de Ti para el reactor MF (electrodo 3D). Los resultados demuestran que el MF-Reactor se destaca por reducir dos factores importantes en la oxidación electroquímica, la resistencia óhmica asociada con el concepto de microfluidos y las limitaciones de transferencia de masa asociadas con la configuración de flujo continuo. Además, permite operar a una menor densidad de corriente efectiva debido a su mayor área de superficie anódica activa. La fotoelectrólisis da como resultado una eliminación más rápida de todos los antibióticos estudiados en el reactor MF y la celda E, en comparación con la electrólisis única, lo que destaca la importancia de los procesos de oxidación electroquímica mediados por luz ultravioleta

Scale-up of Ru-based mesh anodes for the degradation of synthetic hospital wastewater

The disposal of hospital wastewaters, particularly urine with high concentrations of pharmaceuticals, is a critical problem. These pharmaceuticals can enter the environment and lead to the development of superbacteria (in the case of antibiotics) due to the inefficiency of conventional treatment of these aqueous wastes. Hence, this report focuses on the scale-up of a photoelectrochemical (PEC) system equipped with a Ru-based mixed metal oxide anode (MMO-RuO2TiO2) for the efficient removal of synthetic urine polluted with three antibiotics of different therapeutic classes (i.e., meropenem, penicillin G, and chloramphenicol). In addition, the elimination of the antibiotic effect of synthetic polluted urine after the treatments was examined. A conventional mixed electrochemical cell (MEC) with 0.15 L capacity and a microfluidic flow-through cell (MFC) with a 2.25 L reservoir were compared, and the same current density and charge passed were applied in both cells. In both cases, MMO-RuO2TiO2 anodes were used (with a 16.5-fold increase in the geometric area from MEC to MFC) and the synthetic urine was doped with 50 mg L−1 of each antibiotic. The results demonstrate that, although photoelectrolysis attained the efficient removal of all antibiotics in both systems, the removal in the MFC was faster. This outcome is attributed to the improved mechanical design of the microfluidic cell. An evaluation using different bacteria (E. coli and E. faecalis) showed no residual antibiotic effect remained after PEC treatment regardless of the system used. These data indicate that this technology is efficient and can ensure the safe disposal of treated polymedicated urine. Additionally, a smaller amount of energy is spent to remove antibiotics, an order of magnitude less in PECs, especially in MFCs (2-fold less than for MECs). Thus, the treatment of antibiotics using MFCs is promising to reduce the dangers of polymedicated hospital urine.La eliminación de aguas residuales hospitalarias, particularmente orina con altas concentraciones de productos farmacéuticos, es un problema crítico. Estos productos farmacéuticos pueden ingresar al medio ambiente y provocar el desarrollo de superbacterias (en el caso de los antibióticos) debido a la ineficiencia del tratamiento convencional de estos desechos acuosos. Por lo tanto, este informe se centra en la ampliación de un sistema fotoelectroquímico (PEC) equipado con un ánodo de óxido de metal mixto basado en Ru (MMO-RuO 2 TiO 2) para la eliminación eficaz de orina sintética contaminada con tres antibióticos de diferentes clases terapéuticas (es decir, meropenem, penicilina G y cloranfenicol). Además, se examinó la eliminación del efecto antibiótico de la orina contaminada sintética después de los tratamientos. Se compararon una celda electroquímica mixta convencional (MEC) con una capacidad de 0,15 L y una celda de flujo continuo (MFC) de microfluidos con un depósito de 2,25 L, y se aplicó la misma densidad de corriente y carga en ambas celdas. En ambos casos se utilizaron ánodos de MMO-RuO 2 TiO 2 (con un aumento del área geométrica de MEC a MFC de 16,5 veces) y la orina sintética se dopó con 50 mg L- 1de cada antibiótico. Los resultados demuestran que, aunque la fotoelectrólisis logró la eliminación eficiente de todos los antibióticos en ambos sistemas, la eliminación en el MFC fue más rápida. Este resultado se atribuye al diseño mecánico mejorado de la celda microfluídica. Una evaluación utilizando diferentes bacterias ( E. coli y E. faecalis) no mostró ningún efecto antibiótico residual después del tratamiento con PEC, independientemente del sistema utilizado. Estos datos indican que esta tecnología es eficiente y puede garantizar la eliminación segura de la orina polimedicada tratada. Además, se gasta una menor cantidad de energía para eliminar los antibióticos, un orden de magnitud menor en las PEC, especialmente en las MFC (2 veces menos que en las MEC). Por lo tanto, el tratamiento de antibióticos con MFC es prometedor para reducir los peligros de la orina hospitalaria polimedicada

Endomicroscopic and transcriptomic analysis of impaired barrier function and malabsorption in environmental enteropathy

Introduction: Environmental enteropathy (EE) is associated with growth failure, micronutrient malabsorption and impaired responses to oral vaccines. We set out to define cellular mechanisms of impaired barrier function in EE and explore protective mechanisms. Methods: We studied 49 adults with environmental enteropathy in Lusaka, Zambia using confocal laser endomicroscopy (CLE); histology, immunohistochemistry and mRNA sequencing of small intestinal biopsies; and correlated these with plasma lipopolysaccharide (LPS) and a zinc uptake test. Results: CLE images (median 134 for each study) showed virtually ubiquitous small intestinal damage. Epithelial defects, imaged by histology and claudin 4 immunostaining, were predominantly seen at the tips of villi and corresponded with leakage imaged in vivo by CLE. In multivariate analysis, circulating log-transformed LPS was correlated with cell shedding events (β = 0.83; P = 0.035) and with serum glucagon-like peptide-2 (β = -0.13; P = 0.007). Zinc uptake from a test dose of 25mg was attenuated in 30/47 (64%) individuals and in multivariate analysis was reduced by HIV, but positively correlated with GLP-2 (β = 2.72; P = 0.03). There was a U-shaped relationship between circulating LPS and villus surface area. Transcriptomic analysis identified 23 differentially expressed genes in severe enteropathy, including protective peptides and proteins. Conclusions: Confocal endomicroscopy, claudin 4 immunostaining and histology identify epithelial defects which are probably sites of bacterial translocation, in the presence of which increased epithelial surface area increases the burden of translocation. GLP 2 and other protective peptides may play an important role in mucosal protection in EE

Platinum–rhodium–tin/carbon electrocatalysts for ethanol oxidation in acid media: effect of the precursor addition order and the amount of tin

Carbon-supported Pt x –Rh y –Sn z catalysts (x:y:z = 3:1:4, 6:2:4, 9:3:4) are prepared by Pt, Rh, and Sn precursors reduction in different addition order. The materials are characterized by X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy techniques and are evaluated for the electrooxidation of ethanol in acidic media by cyclic voltammetry, chronoamperometry, and anode potentiostatic polarization. The influence of both the order in which the precursors are added and the composition of metals in the catalysts on the electrocatalytic activity and physico-chemical characteristics of Pt x –Rh y –Sn z /C catalysts is evaluated. Oxidized Rh species prevail on the surface of catalysts synthesized by simultaneous co-precipitation, thus demonstrating the influence of synthesis method on the oxidation state of catalysts. Furthermore, high amounts of Sn in composites synthesized by co-precipitation result in very active catalysts at low potentials (bifunctional effect), while medium Sn load is needed for sequentially deposited catalysts when the electronic effect is most important (high potentials), since more exposed Pt and Rh sites are needed on the catalyst surface to alcohol oxidation. The Pt3–Rh1–Sn4/C catalyst prepared by co-precipitation is the most active at potentials lower than 0.55 V (related to bifunctional effect), while the Pt6–Rh2–Sn4/C catalyst, prepared by sequential precipitation (first Rh and, after drying, Pt + Sn), is the most active above 0.55 V.The authors thank the Brazilian National Council of Technological and Scientific Development-CNPq (Grants: 402243/2012-9, 303630/2012-4, 474261/2013-1, 407274/2013-8, and 310282/2013-6) for the scholarships and financial support for this work

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead