75 research outputs found
Field testing of portable led flasher for nominal power measurements of pv-modules on-site
Nominal power measurements of individual PV modules are needed to quantify the critical modules of PV plants offering lower energy production than expected. Today’s state of the art procedure of shipping a small number of modules to a laboratory is time- and cost intensive and it bears the chance of accidental damage. The Portable LED Flasher (PLF) was developed to require no dismounting of the modules. The quality of the PLF was tested on three PV plants in Switzerland. Additionally, ten PV modules of each plant were measured in the certified indoor laboratory of SUPSI, resulting in a maximum deviation of 3% of the STC values. Furthermore, a round robin test on a single crystalline silicon reference module at 25°C was performed at the JRC’s ESTI laboratory, the Swiss Mobile Flasher Bus and SUPSI resulting in a maximum deviation of the mean values below 1% compared to the PLF. A throughput of up to 150 modules or 500 modules respectively per day is expected and the total measurement costs are estimated to be about a tenth of the costs compared to an indoor laboratory. Module temperature measurement is crucial for a low total uncertainty. Thus, methods such as pre-shadowing of the module and approximation of cell temperature are the current focus of further improvement of the PLF measurement method
State-of-the-art for assessment of solar energy technologies 2019
To realize the EU target of energy transition to a carbon neutral energy system, wide scale deployment of photovoltaic solar energy is required. This report describes the contribution of the European Solar Test Installation to enable this transition.JRC.C.2-Energy Efficiency and Renewable
Second international spectroradiometer intercomparison: results and impact on PV device calibration
This paper describes the results of an intercomparison of spectroradiometers for measuring global normal incidence and direct normal incidence spectral irradiance in the visible and in the near infrared, together with an assessment of the impact these results may have on the calibration of the short circuit current (I-sc) of triple-junction photovoltaic devices and on the relevant spectral mismatch calculation. The intercomparison was conducted by six European scientific laboratories and a Japanese industrial partner. Seven spectroradiometer systems, for a total of 13 different instruments/channels using two different technologies and made by four different manufacturers were involved. This group of systems represents a good cross section of the instrumentation for solar spectrum measurements available to date. The instruments were calibrated by each partner prior to the intercomparison following their usual procedure and traceability route in order to verify the entire measurement and traceability chain. The difference in measured spectral irradiance showed to have an impact on the calibration of a set of Iso-Type cells varying from +/- 2% to +/- 14% for middle and bottom cell, respectively
Second international spectroradiometer intercomparison: preliminary results and impact on PV device calibration
This paper describes the preliminary results of an intercomparison of spectroradiometers for global (GNI) and direct normal incidence (DNI) irradiance in the visible (VIS) and near infrared (NIR) spectral regions together with an assessment of the impact these results may have on the calibration of triple-junction photovoltaic devices and on the relevant spectral mismatch calculation. The intercomparison was conducted by six European scientific laboratories and a Japanese industrial partner. Seven institutions and seven spectroradiometer systems, representing different technologies and manufacturers were involved, representing a good cross section of the todays available instrumentation for solar spectrum measurements
Hacia el esclarecimiento del rol del aniĂłn cloruro en la hipertensiĂłn arterial: su vĂnculo con el daño oxidativo en el riñón
IntroducciĂłn: Se desconoce el papel del aniĂłn cloruro en los efectos deletĂ©reos del consumo excesivo de sal (NaCl) y si sus efectos son independientes de la presencia del sodio. Objetivo: Demostrar que tanto una sobrecarga de cloruro como una sobrecarga de sodio en la dieta producen efectos deletĂ©reos, en forma independiente, sobre la presiĂłn arterial sistĂłlica (PAS), la funciĂłn renal y los marcadores de estrĂ©s oxidativo en el riñón. Materiales y mĂ©todos: Ratas Wistar macho fueron divididas en cuatro grupos (n = 8/grupo) y fueron alimentadas con diferentes dietas durante tres semanas: C: control (dieta estándar), NaCl: hipersĂłdica-hiperclĂłrica, Na: hipersĂłdica sin cloruro, Cl: hiperclĂłrica sin sodio. Se determinaron la presiĂłn arterial sistĂłlica (PAS) y la funciĂłn renal y en la corteza renal se evaluĂł la producciĂłn de especies reactivas del ácido tiobarbitĂşrico (en inglĂ©s: TBARS) y la actividad y la expresiĂłn de las enzimas superĂłxido dismutasa (SOD), catalasa (CAT) y glutatiĂłn peroxidasa (GPx). Resultados: Al cabo de tres semanas, la PAS aumentĂł (*) en los dos grupos alimentados con cloruro. La excreciĂłn fraccional de sodio y de cloruro aumentĂł (*) en los grupos NaCl y Na. La diuresis y los TBARS en la corteza renal aumentaron (*) con las tres dietas, sin cambios en la actividad y en la expresiĂłn de SOD y CAT. La actividad de la GPx aumentĂł (*) en los dos grupos que recibieron cloruro; (*p < 0,05 vs C).ConclusiĂłn: Tanto la sobrecarga de sodio como la de cloruro se asocian a mayor estado oxidativo caracterizado por un incremento en la peroxidaciĂłn lipĂdica en la corteza renal. Sin embargo, solo el exceso de cloruro se asocia a mayor actividad de la GPx y de la hipertensiĂłn, sin cambios en la excreciĂłn urinaria de cloruro, sugiriendo un mayor estado prooxidante renal en comparaciĂłn con el grupo Na.Background: The role of the chloride anion on the deleterious effects of excessive salt (NaCl) intake is unknown and whether itseffects are independent of the presence of sodium.Objective: The aim of this study was to demonstrate that both chloride and sodium overload in the diet produce independent deleteriouseffects on systolic blood pressure (SBP), renal function and kidney markers of oxidative stress.Methods: Male Wistar rats were divided into four groups (n=8/group) and fed different diets for three weeks: C: control (standarddiet), NaCl: high sodium-high chloride diet; Na: high sodium without chloride diet and Cl: high chloride without sodium diet. Systolicblood pressure (SBP) and renal function were measured, and thiobarbituric acid reactive species (TBARS) production, andsuperoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) enzymatic activity and expression were evaluated inthe renal cortical tissue.Results: After three weeks, SBP increased (*) in the two groups fed with chloride. Fractional excretion of sodium and chloride increased(*) in the NaCl and Na groups. Diuresis and TBARS increased (*) in the renal cortex with the three diets, with no changesin SOD and CAT activity and expression. GPx activity increased (*) in the two groups that received chloride (* p <0.05 vs. C).Conclusions: Both sodium and chloride overload are associated with a higher oxidative state characterized by increased lipid peroxidationin the renal cortex. However, only chloride overload is associated with higher GPx activity and hypertension without changesin urinary chloride excretion, suggesting a higher renal pro-oxidant state in this experimental group with respect to the Na group.Fil: Kouyoumdzian, Nicolás MartĂn. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto Alberto C. Taquini de Investigaciones en Medicina Traslacional - Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones CardiolĂłgicas "Prof. Dr. Alberto C. Taquini". Instituto Alberto C. Taquini de Investigaciones en Medicina Traslacional; ArgentinaFil: Kim, Gabriel. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica; ArgentinaFil: Robbesaul, Gabriel Damián. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica; ArgentinaFil: Prince, Paula Denise. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BioquĂmica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de BioquĂmica y Medicina Molecular; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de QuĂmica Analitica y FisicoquĂmica. Cátedra de FisicoquĂmica; ArgentinaFil: PuyĂł, Ana MarĂa. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica; ArgentinaFil: Fernández, Belisario E.. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica; ArgentinaFil: Galleano, MĂłnica Liliana. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BioquĂmica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de BioquĂmica y Medicina Molecular; ArgentinaFil: Choi, Marcelo Roberto. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto Alberto C. Taquini de Investigaciones en Medicina Traslacional - Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones CardiolĂłgicas "Prof. Dr. Alberto C. Taquini". Instituto Alberto C. Taquini de Investigaciones en Medicina Traslacional; Argentin
State-of-the-art for assessment of solar energy technologies
Photovoltaics (PV) are expected to make a major contribution to achieving European and global climate change mitigation goals over the coming 35 years. It is the renewable energy technology with the largest scope for cost reduction and efficiency gains, as well as exploiting the largest resource. The rapid technical evolution needs to be matched by standards to ensure the highest level possible of product quality, reliability and sustainability, as well as transparent market conditions. This requires reliable, reproducible and widely applicable measurement protocols for the assessment of electrical performance of PV devices of traditional as well as emerging PV technologies. The Joint Research Centre (JRC) plays a prominent role in developing, validating and implementing such measurement protocols, exploiting more than 35 years of expertise developed in the European Solar Test Installation (ESTI), the European Commission’s reference laboratory to validate electrical performance and lifetime of PV devices. The JRC works together with policy makers, industry and the research community to monitor the progress of PV technology and helps develop the solutions for the future. This directly supports the European Union’s objective of attaining an increasing share of renewable energies in the market (20% in 2020 and at least 32% in 2030).
ESTI is an ISO/IEC 17025 accredited calibration laboratory. As such, it is involved in benchmarking, intercomparisons (bilateral and round robin (RR)) and proficiency tests to maintain and improve its measurement capabilities for solar irradiance and electrical performance of PV devices. The results of these international activities is directly used, mainly through the International Electrotechnical Commission’s Technical Committee 82 (IEC TC 82), as input for revision of existing standards or for development of new standards for assessment of the electrical performance of PV devices. This work concerns both measurement methods and PV technologies. Furthermore, ESTI actively promotes transfer of knowledge about the measurement procedures to the European and International research community, provides the PV traceability chain by generating PV reference materials for its partners and clients and offers verification of PV devices (mainly based on new technologies).
In this report the activities of 2018 are summarised. Starting from the traceability chain of solar irradiance measurements according to international standards, the activities of ESTI in establishing the PV traceability chain at its own laboratory is outlined. Then the activities in international intercomparison measurements for the major instruments used in the traceability chain are described, starting from cavity radiometers and spectroradiometers to PV devices (both cells and modules). These serve to establish the traceability, stability and conformity of ESTI calibration measurements. This in-house metrology activity is then used to provide the PV traceability chain to clients and partners by generating reference materials, i.e. by calibrating PV cells and modules for them under the ISO/IEC 17025 accreditation as calibration laboratory. Another crucial activity is to verify those PV devices which claim to have achieved extraordinary performance, be it world record efficiencies or other performance beyond the usual. Last not least, the activities on measurement methods are described, which span from the actual development of new methods and their validation to their implementation into the ESTI quality system and ISO/IEC 17025 accreditation scope.
Thereby, this annual report:
— verifies the status of ESTI’s unique independent traceability chain for solar irradiance measurements;
— summarises benchmarking activities with peer external international organisations;
— summarises results of PV device calibrations performed for EU industry and research organisations;
— provides an update on the adequacy of measurement methods used to assess the electrical performance of PV products and prototypes.JRC.C.2-Energy Efficiency and Renewable
Mate (Ilex paraguariensis) as an etiological agent of neoplasia in the aerodigestive tract an experimental study
Existem estudos que consideram o “chimarrĂŁo” como fator de risco para desenvolvimento do câncer de orofaringe, esĂ´fago e laringe (infusĂŁo de erva mate, Ilex paraguariensis). Comparar a histologia do trato aĂ©ro-digestivo de ratos submetidos ao consumo de erva mate Ilex paraguariensis, com um grupo controle. Setenta e cinco ratos Wistar adultos foram testados, 60 bebendo mate na temperatura ambiente e 15 bebendo água (grupo controle), durante 5 meses. A histologia do trato aĂ©ro-digestivo destes animais foi analisada. Os animais apresentaram alterações nos exames anátomo-patolĂłgicos havendo diferença significativa (p=0,02) entre os que tomaram mate e o grupo controle. Houve diferença estatĂstica entre o peso corporal dos grupos em estudo e o grupo controle (p<0,001). Este estudo indica que o consumo de mate afeta o trato aerodigestivo superior e Ă© responsável pela perda de peso dos animais estudados.There are studies that consider drinking “chimarrĂŁo” (an infusion of mate, Ilex paraguariensis) a risk factor for developing oropharynx, esophagus and larynx cancer. To make a histological comparison between the aerodigestive tracts of a group of rats submitted to the consumption of erva-mate Ilex paraguariensis, with a control group. Seventy-five adult Wistar rats were tested, 60 drinking mate at room temperature and 15 drinking water (control group), during a period of 5 months. The histology of the aerodigestive tracts of these animals was analyzed. The animals presented alterations in the anatomical-pathological exams. There was a significant difference (p=0.02) between those that were given mate and the control group. There is evidence to suggest that the consumption of mate affects the upper aerodigestive tract in the animals studied, but not inducing cancer
Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis
BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
Anastomosis configuration and technique following ileocaecal resection for Crohn's disease: a multicentre study
A limited ileocaecal resection is the most frequently performed procedure for ileocaecal CD and different anastomotic configurations and techniques have been described. This manuscript audited the different anastomotic techniques used in a national study and evaluated their influence on postoperative outcomes following ileocaecal resection for primary CD. This is a retrospective, multicentre, observational study promoted by the Italian Society of Colorectal Surgery (SICCR), including all adults undergoing elective ileocaecal resection for primary CD from June 2018 May 2019. Postoperative morbidity within 30 days of surgery was the primary endpoint. Postoperative length of hospital stay (LOS) and anastomotic leak rate were the secondary outcomes. 427 patients were included. The side to side anastomosis was the chosen configuration in 380 patients (89%). The stapled anastomotic (n = 286; 67%), techniques were preferred to hand-sewn (n = 141; 33%). Postoperative morbidity was 20.3% and anastomotic leak 3.7%. Anastomotic leak was independent of the type of anastomosis performed, while was associated with an ASA grade ≥ 3, presence of perianal disease and ileocolonic localization of disease. Four predictors of LOS were identified after multivariate analysis. The laparoscopic approach was the only associated with a reduced LOS (p = 0.017), while age, ASA grade ≥ 3 or administration of preoperative TPN were associated with increased LOS. The side to side was the most commonly used anastomotic configuration for ileocolic reconstruction following primary CD resection. There was no difference in postoperative morbidity according to anastomotic technique and configuration. Anastomotic leak was associated with ASA grade ≥ 3, a penetrating phenotype of disease and ileo-colonic distribution of CD
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