Bio-Hydrogen Production from Wastewater: A Comparative Study of Low Energy Intensive Production Processes

Billions of litres of wastewater are produced daily from domestic and industrial areas, and whilst wastewater is often perceived as a problem, it has the potential to be viewed as a rich source for resources and energy. Wastewater contains between four and five times more energy than is required to treat it, and is a potential source of bio-hydrogen—a clean energy vector, a feedstock chemical and a fuel, widely recognised to have a role in the decarbonisation of the future energy system. This paper investigates sustainable, low-energy intensive routes for hydrogen production from wastewater, critically analysing five technologies, namely photo-fermentation, dark fermentation, photocatalysis, microbial photo electrochemical processes and microbial electrolysis cells (MECs). The paper compares key parameters influencing H2 production yield, such as pH, temperature and reactor design, summarises the state of the art in each area, and highlights the scale-up technical challenges. In addition to H2 production, these processes can be used for partial wastewater remediation, providing at least 45% reduction in chemical oxygen demand (COD), and are suitable for integration into existing wastewater treatment plants. Key advancements in lab-based research are included, highlighting the potential for each technology to contribute to the development of clean energy. Whilst there have been efforts to scale dark fermentation, electro and photo chemical technologies are still at the early stages of development (Technology Readiness Levels below 4); therefore, pilot plants and demonstrators sited at wastewater treatment facilities are needed to assess commercial viability. As such, a multidisciplinary approach is needed to overcome the current barriers to implementation, integrating expertise in engineering, chemistry and microbiology with the commercial experience of both water and energy sectors. The review concludes by highlighting MECs as a promising technology, due to excellent system modularity, good hydrogen yield (3.6–7.9 L/L/d from synthetic wastewater) and the potential to remove up to 80% COD from influent streams

Impact of obesity on global and regional systolic function in children: a CMR study

International audiencen.

Seebeck Effect in Magnetic Tunnel Junctions

Creating temperature gradients in magnetic nanostructures has resulted in a new research direction, i.e., the combination of magneto- and thermoelectric effects. Here, we demonstrate the observation of one important effect of this class: the magneto-Seebeck effect. It is observed when a magnetic configuration changes the charge based Seebeck coefficient. In particular, the Seebeck coefficient changes during the transition from a parallel to an antiparallel magnetic configuration in a tunnel junction. In that respect, it is the analog to the tunneling magnetoresistance. The Seebeck coefficients in parallel and antiparallel configuration are in the order of the voltages known from the charge-Seebeck effect. The size and sign of the effect can be controlled by the composition of the electrodes' atomic layers adjacent to the barrier and the temperature. Experimentally, we realized 8.8 % magneto-Seebeck effect, which results from a voltage change of about -8.7 {\mu}V/K from the antiparallel to the parallel direction close to the predicted value of -12.1 {\mu}V/K.Comment: 16 pages, 7 figures, 2 table

Use of radar detectors to track attendance of albatrosses at fishing vessels.

Despite international waters covering over 60% of the world's oceans, our understanding of how fisheries in these regions shape ecosystem processes is surprisingly poor. Seabirds are known to forage at fishing vessels, with potential deleterious effects for their population, but the extent of overlap and behavior in relation to ships are poorly known. Using novel biologging devices, which can detect radar emissions to record the position of boats and seabirds, we measured the true extent of the overlap between seabirds and fishing vessels, and generated estimates of the intensity of fishing and distribution of vessels in international waters. During breeding, wandering albatrosses from the Crozet islands patrolled an area of more than 10 million square kilometers and as much as 79.5% of birds equipped with loggers detected vessels, at distances up to 2500 km from the colony, modifying their natural foraging behavior to attend boats. The extent of this overlap has widespread implications for bycatch risk in seabirds and reveals the areas of intense fishing throughout the ocean. We suggest that seabirds equipped with radar detectors are excellent monitors of the presence of vessels in the southern ocean, offering a new way to monitor fisheries. The method used opens new perspectives to monitor the presence of illegal fisheries and to better understand the impact of fisheries on seabirds. This article is protected by copyright. All rights reserved

External sources of clean technology: evidence from the clean development mechanism

New technology is fundamental to sustainable development. However, inventors from industrialized countries often refuse technology transfer because they worry about reverse-engineering. When can clean technology transfer succeed? We develop a formal model of the political economy of North–South technology transfer. According to the model, technology transfer is possible if (1) the technology in focus has limited global commercial potential or (2) the host developing country does not have the capacity to absorb new technologies for commercial use. If both conditions fail, inventors from industrialized countries worry about the adverse competitiveness effects of reverse-engineering, so technology transfer fails. Data analysis of technology transfer in 4,894 projects implemented under the Kyoto Protocol’s Clean Development Mechanism during the 2004–2010 period provides evidence in support of the model

Qualidade de vida no trabalho nivel de estresse dos profissionais das UBS do Distrito Leste do Município de Foz do Iguaçu-PR

Trabalho de conclusão de Residência apresentado ao Programa Multiprofissional em Saúde da Família da Universidade Federal da Integração Latino-Americana, como requisito para obtenção do título de Especialista em Saúde da Família na modalidade de Residência. Orientador: Prof. Dr Thiago Luis de Andrade Barbosa Co-orientador: Prof. Ms. Gilberto Garcia da RochaObjetivo: Avaliar a qualidade de vida no trabalho (QVT) e nível de estresse dos trabalhadores da Atenção Primária à Saúde (APS) do distrito leste de Foz do Iguaçu-PR. Metodologia: Trata-se de estudo transversal no qual participaram 120 profissionais da APS pertencentes a 06 UBS do referido distrito. Os profissionais responderam questionários sociodemográfico, de QVT abreviado (QWLQ-Bref) e Escala do Estresse Percebido (PSS 13). Verificou-se associação da QVT e dos níveis de estresse com variáveis sociodemográficas com uso do teste t de Student, ANOVA, Mann-Whitney e Kruskal-Wallis. Nível de significância adotado foi de 5%. Resultados: A avaliação da QVT dos profissionais foi 62,8±10,0 e associou-se com sexo (p=0,016), idade (p=0,042), presença de dor (p=0,029) e satisfação com trabalho (p=0,002). Em relação aos domínios avaliados da QVT, houve associação com presença de dor e satisfação laboral. O escore total médio de estresse percebido dos participantes foi 24,5±6,0. Notou-se relação com as variáveis percepção quanto à alimentação saudável (p=0,013), presença de dor (p=0,002), dor relacionada ao trabalho (p=0,004) e satisfação com trabalho (p=0,001). Conclusão: Constatou-se satisfatória QVT e níveis médios de estresse dos profissionais o que demanda ações preventivas que melhorem esse panorama na APS do municípioObjective: To evaluate the quality of working life (QWL) and stress level of workers at Primary Health Care (PHC) in the east district of Foz do Iguaçu-PR. Methodology: Cross- sectional study with 120 PHC professionals from 06 basic health units of this district. Professionals answered sociodemographic questionnaire, abbreviated QLW (QWLQ-Bref) and Perceived Stress Scale (PSS 13). We verified the association of QWL and stress levels with sociodemographic variables using Student's t-test, ANOVA, Mann-Whitney and Kruskal-Wallis. Level of significance was 5%. Results: The professional QWL assessment was 62.8 ± 10.0 and was associated with gender (p=0.016), age (p=0.042), presence of pain (p = 0.029) and work satisfaction (p=0.002). In relation to the evaluated domains of QWL, there was an association with presence of pain and job satisfaction. The mean total perceived stress score of the participants was 24.5 ± 6.0. There was a relationship with the variables of perception regarding healthy eating (p=0.013), presence of pain (p=0.002), pain related to work (p=0.004) and satisfaction with work (p=0.001). Conclusion: We observed satisfactory QWL and mean levels of stress of PHC workers that demand improvement of this situationObjetivo: Evaluar la calidad de vida en el trabajo (QVT) y nivel de estrés de los trabajadores de la Atención Primaria a la Salud (APS) del distrito este de Foz do Iguaçu-PR. Metodología: Se trata de un estudio transversal en el que participaron 120 profesionales de la APS pertenecientes a 06 UBS de dicho distrito. Los profesionales respondieron cuestionarios sociodemográficos, de QVT abreviado (QWLQ-Bref) y Escala del estrés percibido (PSS 13). Se verificó asociación de QVT y de los niveles de estrés con variables sociodemográficas con el uso del test t de Student, ANOVA, Mann-Whitney y Kruskal-Wallis. El nivel de significancia adoptado fue del 5%. Resultados: La evaluación de la QVT de los profesionales fue de 62,8 ± 10,0 y se asoció con sexo (p=0,016), edad (p=0,042), presencia de dolor (p=0,029) y satisfacción con el trabajo (p=0,029) 0,002). En relación a los ámbitos evaluados de la QVT, hubo asociación con presencia de dolor y satisfacción laboral. La puntuación total promedio de estrés percibido de los participantes fue de 24,5 ± 6,0. Se observó relación con las variables percepción en cuanto a la alimentación sana (p=0,013), presencia de dolor (p=0,002), dolor relacionado al trabajo (p=0,004) y satisfacción con el trabajo (p=0,001). Conclusión: Se constató satisfactoria QVT y niveles medios de estrés de los profesionales lo que demanda acciones preventivas que mejoren ese panorama en la APS del municipi

The Hubble Constant from Observations of the Brightest Red Giant Stars in a Virgo-Cluster Galaxy

The Virgo and Fornax clusters of galaxies play central roles in determining the Hubble constant H_0. A powerful and direct way of establishing distances for elliptical galaxies is to use the luminosities of the brightest red-giant stars (the TRGB luminosity, at M_I = -4.2). Here we report the direct observation of the TRGB stars in a dwarf elliptical galaxy in the Virgo cluster. We find its distance to be 15.7 +- 1.5 Megaparsecs, from which we estimate a Hubble constant of H_0 = 77 +- 8 km/s/Mpc. Under the assumption of a low-density Universe with the simplest cosmology, the age of the Universe is no more than 12-13 billion years.Comment: 12 pages, LaTeX, with 2 postscript figures; in press for Nature, July 199