Transient phenomenological modelling of photoelectrochemical cells for water splitting: application to undoped hematite electrodes

A phenomenological model is proposed for a better understanding of the basic mechanismsof photoelectrochemical (PEC) cells. The main assumptions of the one-dimensionaltransient phenomenological model are: i) bulk recombination of the conduction bandelectrons with holes in the valence band; ii) the mobile charge transport takes place viadiffusion, which arises from the concentration profiles, and migration, caused bya macroscopic electric field; iii) negligible effects of microscopic electric fields in the celland screening effects, as well as negligible Helmholtz and diffuse layers. For modelingpurposes, the photoanode was assumed to be a homogeneous nanocrystalline hematitestructure, with thickness L, porosity 3p and tortuosity s. The TCO/semiconductor interfacewas modeled as an ideal ohmic contact, while the electrolyte/platinized TCO interface wasdescribed by a ButlereVolmer approach. An alkaline electrolyte solution was used,allowing the transport of the ionic species from the counter-electrode to the photoanode.The continuity and transport governing equations are defined for the mobile speciesinvolved: electrons in the conduction band of the semiconductor, holes in the valence bandand hydroxyl ions in the electrolyte. Simulated IeV characteristics were computed and thecorresponding results compared with the experimental values. The simulated results werein straight agreement with the experimental data

Dye-sensitized solar cells: A safe bet for the future.

This review describes the main features of dye-sensitized solar cells (DSCs) and highlights recent breakthroughs in this promising thin-film photovoltaic (PV) technology. After a brief presentation of the commercially available technologies, the general operation principles and the most relevant characteristics of DSCs are summarized. Recent major advances in high efficiency sensitizers, nanostructured semiconductors and robust electrolytes offer an opportunity for DSCs integration into the marketplace. With attractive features, like low-cost potential, simple processing, wide range of applicability - from low-power electronics to semi-transparent windowpanes for electricity generation - and good performance under typical operating conditions, these cells are one step from large-scale commercialization. We describe major strategies that are under way to make DSCs a key technology in the future PV paradigm

Tendência da mortalidade por câncer e principais tipos, segundo macrorregiões do Estado de Mato Grosso, 2000 a 2015

Objective: To describe the mortality trend from all causes of cancer and the five main causes in the state of Mato Grosso, Brazil, from 2000 to 2015. Methods: This is a descriptive, ecological, time series study, with data referring to deaths of residents of Mato Grosso due to neoplasms (ICD-10 codes C00 to C97), from the Mortality Information System (SIM). Time trend analyzes of the standardized mortality rate from all causes of cancer and five specific causes of cancer (lung, prostate, breast, colorectal and cervix) for the state and according to macroregions (South, West, North, East and Center -North) were performed using linear regression (p-value<0.05). Results: From 2000 to 2015, 28,525 deaths from all causes of cancer in residents of the state of Mato Grosso were recorded. An increasing trend was observed for all causes of cancer, in addition to lung, breast and colorectal cancers. Southern and Northern macroregions showed an increasing trend for all causes, breast and colorectal; North-Central for breast and colorectal. East was increasing for all causes, prostate and colorectal, and decreasing for cervix. Conclusions: In the state of Mato Grosso, there was an increasing trend in mortality from all causes of cancer and from specific causes, with emphasis on breast and colorectal cancer in most macroregions.Objetivo: Descrever a tendência da mortalidade por todas as causas de câncer e das cinco principais causas no Estado de Mato Grosso, Brasil, no período 2000 a 2015. Métodos: Trata-se de um estudo descritivo, ecológico, do tipo série temporal, com dados referentes aos óbitos de residentes de Mato Grosso por neoplasias (códigos C00 a C97 da CID-10), provenientes do Sistema de Informações sobre Mortalidade (SIM). A tendência temporal da taxa de mortalidade padronizada de todas as causas de câncer e cinco causas específicas de câncer (pulmão, próstata, mama feminina, colorretal e colo do útero) para o estado e segundo macrorregiões (Sul, Oeste, Norte, Leste e Centro-Norte) foi analisada por meio de regressão linear (p-valor<0,05). Resultados: De 2000 a 2015, ocorreram 28.525 óbitos por todas as causas de câncer em residentes no Estado de Mato Grosso. Tendência crescente foi observada para todas as causas de câncer, além dos cânceres de pulmão, mama e colorretal. Macrorregiões Sul e Norte apresentaram tendência crescente para todas as causas, mama e colorretal; Centro-Norte para mama e colorretal. Na Macrorregião Leste foi crescente para todas as causas, próstata e colorretal, e decrescente para colo do útero. Conclusões: No Estado de Mato Grosso, verificou-se tendência crescente da mortalidade por todas as causas de câncer e por causas específicas, com destaque para mama e colorretal na maioria das macrorregiões

Simplified sewerage to prevent urban leptospirosis transmission: a cluster non-randomised controlled trial protocol in disadvantaged urban communities of Salvador, Brazil.

INTRODUCTION: Leptospirosis is a globally distributed zoonotic and environmentally mediated disease that has emerged as a major health problem in urban slums in developing countries. Its aetiological agent is bacteria of the genus Leptospira, which are mainly spread in the urine of infected rodents, especially in an environment where adequate sanitation facilities are lacking, and it is known that open sewers are key transmission sources of the disease. Therefore, we aim to evaluate the effectiveness of a simplified sewerage intervention in reducing the risk of exposure to contaminated environments and Leptospira infection and to characterise the transmission mechanisms involved. METHODS AND ANALYSIS: This matched quasi-experimental study design using non-randomised intervention and control clusters was designed to assess the effectiveness of an urban simplified sewerage intervention in the low-income communities of Salvador, Brazil. The intervention consists of household-level piped sewerage connections and community engagement and public involvement activities. A cohort of 1400 adult participants will be recruited and grouped into eight clusters consisting of four matched intervention-control pairs with approximately 175 individuals in each cluster in baseline. The primary outcome is the seroincidence of Leptospira infection assessed through five serological measurements: one preintervention (baseline) and four postintervention. As a secondary outcome, we will assess Leptospira load in soil, before and after the intervention. We will also assess Leptospira exposures before and after the intervention, through transmission modelling, accounting for residents' movement, contact with flooding, contaminated soil and water, and rat infestation, to examine whether and how routes of exposure for Leptospira change following the introduction of sanitation. ETHICS AND DISSEMINATION: This study protocol has been reviewed and approved by the ethics boards at the Federal University of Bahia and the Brazilian National Research Ethics Committee. Results will be disseminated through peer-reviewed publications and presentations to implementers, researchers and participating communities. TRIAL REGISTRATION NUMBER: Brazilian Clinical Trials Registry (RBR-8cjjpgm)

Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

Search for stop and higgsino production using diphoton Higgs boson decays

Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top-quark (stop) and the Higgs boson (higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the stop mass below 360 to 410 GeV, depending on the higgsino mass

Severe early onset preeclampsia: short and long term clinical, psychosocial and biochemical aspects

Preeclampsia is a pregnancy specific disorder commonly defined as de novo hypertension and proteinuria after 20 weeks gestational age. It occurs in approximately 3-5% of pregnancies and it is still a major cause of both foetal and maternal morbidity and mortality worldwide1. As extensive research has not yet elucidated the aetiology of preeclampsia, there are no rational preventive or therapeutic interventions available. The only rational treatment is delivery, which benefits the mother but is not in the interest of the foetus, if remote from term. Early onset preeclampsia (<32 weeks’ gestational age) occurs in less than 1% of pregnancies. It is, however often associated with maternal morbidity as the risk of progression to severe maternal disease is inversely related with gestational age at onset2. Resulting prematurity is therefore the main cause of neonatal mortality and morbidity in patients with severe preeclampsia3. Although the discussion is ongoing, perinatal survival is suggested to be increased in patients with preterm preeclampsia by expectant, non-interventional management. This temporising treatment option to lengthen pregnancy includes the use of antihypertensive medication to control hypertension, magnesium sulphate to prevent eclampsia and corticosteroids to enhance foetal lung maturity4. With optimal maternal haemodynamic status and reassuring foetal condition this results on average in an extension of 2 weeks. Prolongation of these pregnancies is a great challenge for clinicians to balance between potential maternal risks on one the eve hand and possible foetal benefits on the other. Clinical controversies regarding prolongation of preterm preeclamptic pregnancies still exist – also taking into account that preeclampsia is the leading cause of maternal mortality in the Netherlands5 - a debate which is even more pronounced in very preterm pregnancies with questionable foetal viability6-9. Do maternal risks of prolongation of these very early pregnancies outweigh the chances of neonatal survival? Counselling of women with very early onset preeclampsia not only comprises of knowledge of the outcome of those particular pregnancies, but also knowledge of outcomes of future pregnancies of these women is of major clinical importance. This thesis opens with a review of the literature on identifiable risk factors of preeclampsia