285 research outputs found

    Identifying (subsurface) anthropogenic heat sources that influence temperature in the drinking water distribution system

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    The water temperature in the drinking water distribution system and at the customers’ taps approaches the surrounding soil temperature at ca. 1 meter depth. Water temperature is an important determinant of water quality, since it influences physical, chemical and biological processes, such as absorption of chemicals, microbial growth and chlorine decay. In the Netherlands drinking water is distributed without additional residual disinfectant and the temperature of drinking water at the customers’ tap is not allowed to exceed 25 ºC. Routine water quality samples at the tap in urban areas have shown locations with relatively high soil temperatures compared to the expected modelled soil temperatures, which indicate so called ‘underground hot-spots’. In the last decades, the urban sub-surface is getting more occupied with various types of sub-surface infrastructures and some of these can be heat sources. A few recent studies tackle the anthropogenic sources and their influence on the underground, at coarse spatial scales. Little is known about the urban shallow underground heat profile on small spatial scales, of the order of 10 m × 10 m. Our research focuses on developing a method to identify and to localise potential underground hot-spots at −1.0 m at a small spatial scale. In this article we describe a method to find anthropogenic heat sources that influence temperature in the drinking water distribution system through a combination of mapping urban anthropogenic heat sources, modelling the soil temperature and extensive measurements in Rotterdam

    Gynoecium size and ovule number are interconnected traits that impact seed yield

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    Angiosperms form the biggest group of land plants and display an astonishing diversity of floral structures. The development of the flowers greatly contributed to the evolutionary success of the angiosperms as they guarantee efficient reproduction with the help of either biotic or abiotic vectors. The female reproductive part of the flower is the gynoecium (also called pistil). Ovules arise from meristematic tissue within the gynoecium. Upon fertilization, these ovules develop into seeds while the gynoecium turns into a fruit. Gene regulatory networks involving transcription factors and hormonal communication regulate ovule primordium initiation, their spacing on the placenta, and ovule development. Ovule number and gynoecium size are usually correlated and several genetic factors that impact these traits have been identified. Understanding and fine-tuning the gene regulatory networks influencing ovule number and pistil length opens up strategies for crop yield improvement, which is pivotal in light of a rapidly growing world population. In this review, we present an overview of the current knowledge of the genes and hormones involved in determining ovule number and gynoecium size. We propose a model for the gene regulatory network that guides the developmental processes that determine seed yield

    Divergent responses of serum testosterone and cortisol in athlete men after a marathon race

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    Physical exercise alters homeostasis, as it requires prompt mobilization of metabolic sources. In this study, we measured serum testosterone (T) and cortisol (C) levels and the muscle-wastage enzymes CK, CKMB and LDH in 20 healthy male athletes (ages 25 to 40 years) in response to a marathon race (42.2 km). Venous blood samples were drawn in 3 different periods: (i) in the morning, 48 h before the competition (control), (ii) at the end of the race (end), and (iii) in the next morning, 20 h after the race (recovery). At the end, T was significantly lower (from 673 to 303 ng/dl) and C higher (from 20.3 to 42.5 µg/dl) as compared to the control period. At recovery, both were virtually identical to control levels. CK, CKMB and LDH were significantly higher at the end of the competition and even higher in the recovering period (except for CKMB), characterizing muscle wastage. CK and LDH disclosed a significant negative correlation with T (-0.412 and -0.546, respectively), whereas CKMB correlated positively with C (0.4521). We conclude that the inverse correlation observed between T and C levels, and the pattern of CK, CKMB and LDH increase, allow us to confirm that a marathon race may cause a marked physical stress, resulting in a distinct hormonal imbalance and severe cellular damage.O exercício físico altera a homeostase, pois requer rápida mobilização de fontes metabólicas. Neste estudo, analisamos a resposta dos níveis séricos de testosterona (T) e cortisol (C) e das enzimas de desgaste muscular CK, CKMB e LDH, em 20 atletas masculinos sadios (25 a 40 anos), participantes de uma maratona (42,2 km). Coletas de sangue venoso foram feitas em 3 períodos: (i) pela manhã, 48 h antes da maratona (controle), (ii) logo após o término da corrida (final) e (iii) na manhã seguinte, 20 h após a realização da prova (recuperação). Ao final, T estava significantemente mais baixa (de 673 para 303 ng/dl) e C mais elevado (de 20,3 para 42,5 µg/dl) que no período controle. Na recuperação, ambos praticamente retornaram aos níveis basais. CK, CKMB e LDH estavam significantemente mais elevadas ao final da corrida e mais ainda na recuperação (exceto a CKMB), caracterizando o desgaste muscular. Enquanto CK e LDH apresentaram significante correlação negativa com a T (-0,412 e -0,546, respectivamente), CKMB correlacionou-se positivamente com o C (0,4521). Concluímos que a correlação inversa entre T e C, e o comportamento das enzimas CK, CKMB e LDH, permite comprovar que uma corrida de maratona causa intenso stress físico, provocando desequilíbrio hormonal e lesão celular severa.Universidade Federal de São Paulo (UNIFESP) Departamento de Medicina Centro de Medicina da Atividade Física e do EsporteUNIFESP, Depto. de Medicina Centro de Medicina da Atividade Física e do EsporteSciEL

    Successful Thrombectomy via a Surgically Reopened Umbilical Vein for Extended Portal Vein Thrombosis Caused by Portal Vein Embolization prior to Extended Liver Resection

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    Selective portal vein embolization (PVE) before extended liver surgery is an accepted method to stimulate growth of the future liver remnant. Portal vein thrombosis (PVT) of the main stem and the non-targeted branches to the future liver remnant is a rare but major complication of PVE, requiring immediate revascularization. Without revascularization, curative liver surgery is not possible, resulting in a potentially life-threatening situation. We here present a new surgical technique to revascularize the portal vein after PVT by combining a surgical thrombectomy with catheter-based thrombolysis via the surgically reopened umbilical vein. This technique was successfully applied in a patient who developed thrombosis of the portal vein main stem, as well as the left portal vein and its branches to the left lateral segments after selective right-sided PVE in preparation for an extended right hemihepatectomy. The advantage of this technique is the avoidance of an exploration of hepatoduodenal ligament and a venotomy of the portal vein. The minimal surgical trauma facilitates additional intravascular thrombolytic therapy as well as the future right extended hemihepatectomy. We recommend this technique in patients with extensive PVT in which percutaneous less invasive therapies have been proven unsuccessful

    Primary adrenal insufficiency in adults: 150 years after Addison

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    Thomas Addison first described, 150 years ago, a clinical syndrome characterized by salt-wasting and skin hyperpigmentation, associated with a destruction of the adrenal gland. Even today, over a century after Addison's report, primary adrenal insufficiency can present as a life-threatening condition, since it frequently goes unrecognized in its early stages. In the 1850 s, tuberculous adrenalitis was present in the majority of patients, but nowadays, autoimmune Addison's disease is the most common cause of primary adrenal insufficiency. In the present report, we show the prevalence of different etiologies, clinical manifestations and laboratorial findings, including the adrenal cortex autoantibody, and 21-hydroxylase antibody in a Brazilian series of patients with primary adrenal insufficiency followed at Divisão de Endocrinologia da Universidade Federal de São Paulo (UNIFESP) and at Faculdade de Medicina de Ribeirão Preto - USP (FMRP-USP).Thomas Addison descreveu pela primeira vez, há 150 anos, uma síndrome clínica de perda de sal em indivíduos com hiperpigmentação cutânea, associada à destruição da glândula adrenal. Atualmente, a insuficiência adrenal ainda representa uma condição de risco, pois seu diagnóstico é freqüentemente não reconhecido nas fases iniciais da doença. A adrenalite tuberculosa era a causa mais freqüente na maioria dos casos descritos inicialmente, mas, na atualidade, a doença de Addison auto-imune está presente em uma grande porcentagem de pacientes com insuficiência adrenal primária. No presente trabalho, apresentamos a prevalência das diferentes causas, manifestações clínicas e achados laboratoriais, incluindo a determinação de anticorpos anticórtex adrenal e anti-21-hidroxilase em pacientes acompanhados com insuficiência adrenal primária seguidos nos Ambulatórios das Divisões de Endocrinologia da Universidade Federal de São Paulo (UNIFESP) e da Faculdade de Medicina de Ribeirão Preto - USP (FMRP-USP).Universidade Federal de São Paulo (UNIFESP)Universidade de São Paulo Faculdade de Medicina de Ribeirão Preto Departamento de Clínica MédicaUniversidade de São Paulo Faculdade de Medicina de Ribeirão Preto Departamento de FisiologiaUNIFESPSciEL

    REM34 and REM35 control female and male gametophyte development in Arabidopsis thaliana

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    The REproductive Meristem (REM) gene family encodes for transcription factors belonging to the B3 DNA binding domain superfamily. In Arabidopsis thaliana the REM gene family is composed of 45 members, preferentially expressed during flower, ovule and seed development. Only a few members of this family have been functionally characterized: VERNALIZATION1 (VRN1) and most recently TARGET OF FLC AND SVP1 (TFS1) regulate flowering time and VERDANDI (VDD), together with VALKYRIE (VAL) control the death of the receptive synergid cell in the female gametophyte. We investigated the role of REM34, REM35 and REM36, three closely related and linked genes similarly expressed in both female and male gametophytes. Simultaneous silencing by RNA interference (RNAi) caused about 50% of the ovules to remain unfertilized. Careful evaluation of both ovule and pollen development showed that this partial sterility of the transgenic RNAi lines was due to a post meiotic block in both female and male gametophytes. Furthermore, protein interaction assays revealed that REM34 and REM35 interact, which suggests that they work together during the first stages of gametogenesis

    Drinking water temperature around the globe: Understanding, policies, challenges and opportunities

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    Water temperature is often monitored at water sources and treatment works; however, there is limited monitoring of the water temperature in the drinking water distribution system (DWDS), despite a known impact on physical, chemical and microbial reactions which impact water quality. A key parameter influencing drinking water temperature is soil temperature, which is influenced by the urban heat island effects. This paper provides critique and comprehensive summary of the current knowledge, policies and challenges regarding drinking water temperature research and presents the findings from a survey of international stakeholders. Knowledge gaps as well as challenges and opportunities for monitoring and research are identified. The conclusion of the study is that temperature in the DWDS is an emerging concern in various countries regardless of the water source and treatment, climate conditions, or network characteristics such as topology, pipe material or diameter. More research is needed, especially to determine (i) the effect of higher temperatures, (ii) a legislative limit on temperature and (iii) measures to comply with this limit
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