65 research outputs found

    Early degradation of PV modules and guaranty conditions

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    CIEMAT PVLabDER has largely increased its demand on testing and characterizing PV plants, according to the fast growth of PV installed capacity in Spain. One of the topics in which manufacturers, promoters, and owners of the plants are more interested in, is the possible degradation of PV modules and its relationship to guarantee contracts, as it is related to subsidies. This paper presents some findings in campaigns of PV plants evaluation carried out during last years. This evaluation usually consists of visual inspection, I-V curve measurement in the fields (the whole plant or selected areas), thermal evaluation by IR imaging, and, in some cases, measurement of the I-V characteristic and thermal behaviour of selected modules in the plant, chosen by the laboratory. It must be noticed that new defects that grow when the module is into operation may appear in modules initially free of them (named as hidden manufacturing defects). Usually some of these hidden defects that only appear in normal operation are not detected in reliability tests (EN61215 or EN 61646) [4][5] due to the different operational conditions of the module in the standard tests and in the field (serial-parallel connection of many PV modules, power inverter influence, over voltage on wires, etc.

    Early degradation of PV modules and guaranty conditions

    Get PDF
    CIEMAT PVLabDER has largely increased its demand on testing and characterizing PV plants, according to the fast growth of PV installed capacity in Spain. One of the topics in which manufacturers, promoters, and owners of the plants are more interested in, is the possible degradation of PV modules and its relationship to guarantee contracts, as it is related to subsidies. This paper presents some findings in campaigns of PV plants evaluation carried out during last years. This evaluation usually consists of visual inspection, I-V curve measurement in the fields (the whole plant or selected areas), thermal evaluation by IR imaging, and, in some cases, measurement of the I-V characteristic and thermal behaviour of selected modules in the plant, chosen by the laboratory. It must be noticed that new defects that grow when the module is into operation may appear in modules initially free of them (named as hidden manufacturing defects). Usually some of these hidden defects that only appear in normal operation are not detected in reliability tests (EN61215 or EN 61646) [4][5] due to the different operational conditions of the module in the standard tests and in the field (serial-parallel connection of many PV modules, power inverter influence, over voltage on wires, etc.

    Influence of initial power stabilization over crystalline-Si photovoltaic modules maximum power

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    Measurements that suppliers offer in specification sheets are not always close to the actual power measured in independent laboratories such as CIEMAT. Independent measurements tend to be lower than those printed on the label sometimes even lower than the allowed tolerance indicated by the manufacturer on the same label. Furthermore, a potentially significant power reduction has been reported when Standard EN50380 (which requires photovoltaic (PV) modules to be exposed to more than 20 kWh/m2 of sunlight prior to taking the measurements that appear on the label) is followed. This is the initial power stabilization and this work studies the power stabilization that tends to appear in crystalline PV modules. Crystalline PV modules usually decrease in power around 1%, but decreases >4% have also been reported. These power losses are only detected after the mentioned power stabilizatio

    Thim Films Modules Characterization Under Standard Test Conditions

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    Photovoltaic modules based on the relatively new thin film technology are gaining importance in the photovoltaic market. Some of these modules are made of silicon, consisting of layers of amorphous silicon or microcrystalline silicon. Other thin film PV modules are made of CIS, Cadmium Telluride (CdTe) or less frequently organic compounds. The materials used in thin film technologies pose problems in terms of measuring how much power is generated under standard test conditions (STC). This is due to the fact that the modulesÂŽ power rates could vary depending both on the amount of time they have been exposed to the sun and on their history of sunlight exposure. So it is necessary to know the previous periods of sunlight exposure in order to know the current state of the module. It is necessary to determine an easily accomplishable testing method that ensures the repeatability of the measurements of the power generated. This is essential because in order to have a reliable sample of the PV module population of a large PV plant, a huge number of modules must be measured. This paper shows different tests performed on different commercial thin film PV modules in order to find the best way to obtain measurements. A correlation was tested between sun exposure and power measured. A method for obtaining indoor measurements of these technologies that takes periods of sunlight exposure into account is proposed. Additionally, temperature and irradiance coefficients were also determined for different technologies in order to obtain accurate measurements

    Sequential Colocalization of ERa, PR, and AR Hormone Receptors Using Confocal Microscopy Enables New Insights into Normal Breast and Prostate Tissue and Cancers

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    Multiplex immunohistochemistry (mIHC) use markers staining different cell populations applying widefield optical microscopy. Resolution is low not resolving subcellular co-localization. We sought to colocalize markers at subcellular level with antibodies validated for clinical diagnosis, including the single secondary antibody (combination of anti-rabbit/mouse-antibodies) used for diagnostic IHC with any primary antibody, and confocal microscopy. We explore colocalization in the nucleus (ColNu) of nuclear hormone receptors (ERa, PR, and AR) along with the baseline marker p63 in paired samples of breast and prostate tissues. We established ColNu mIHCF as a reliable technique easily implemented in a hospital setting. In ERa+ breast cancer, we identified different colocalization patterns (nuclear or cytoplasmatic) with PR and AR on the luminal epithelium. A triple-negative breast-cancer case expressed membrane-only ERa. A PR-only case was double positive PR/p63. In normal prostate, we identified an ERa+/p63+/AR-negative distinct population. All prostate cancer cases characteristically expressed ERa on the apical membrane of the AR+ epithelium. We confirmed this using ERa IHC and needle-core biopsies. ColNu mIHCF is feasible and already revealed a new marker for prostate cancer and identified sub-patterns in breast cancer. It could be useful for pathology as well as for functional studies in normal prostate and breast tissues

    SUCCESS POSSIBILITIES OF GRID PARITY IN PARTICULAR CASES IN THE NEW SPANISH REGULATORY FRAMEWORK

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    ABSTRACT: During the last 10 years the Spanish photovoltaic market has experienced one of the most important increases worldwide. The continuous raise on the price of the electricity in Spain, as in other European countries, USA and Japan, as well as the decrease of the cost of solar photovoltaic systems along this decade is opening a new way to reach grid parity point in some particular scenarios. A new Spanish legislation is being performed toward selfconsumption, and it is in this new context where the grid parity in a wide sense could be achieved. This work will study different cases in Spain, in order to determine whether grid parity would be possible along 2012

    RET signalling provides tumorigenic mechanism and tissue specificity for AIP-related somatotrophinomas

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    International audienceIt is unclear how loss-of-function germline mutations in the widely-expressed co-chaperone AIP , result in young-onset growth hormone secreting pituitary tumours. The RET receptor, uniquely co-expressed in somatotrophs with PIT1, induces apoptosis when unliganded, while RET supports cell survival when it is bound to its ligand. We demonstrate that at the plasma membrane, AIP is required to form a complex with monomeric-intracellular-RET, caspase-3 and PKCÎŽ resulting in PIT1/CDKN2A-ARF/p53-apoptosis pathway activation. AIP-deficiency blocks RET/caspase-3/PKCÎŽ activation preventing PIT1 accumulation and apoptosis. The presence or lack of the inhibitory effect on RET-induced apoptosis separated pathogenic AIP variants from non-pathogenic ones. We used virogenomics in neonatal rats to demonstrate the effect of mutant AIP protein on the RET apoptotic pathway in vivo. In adult male rats altered AIP induces elevated IGF-1 and gigantism, with pituitary hyperplasia through blocking the RET-apoptotic pathway. In females, pituitary hyperplasia is induced but IGF-1 rise and gigantism are blunted by puberty. Somatotroph adenomas from pituitary-specific Aip -knockout mice overexpress the RET-ligand GDNF, therefore, upregulating the survival pathway. Somatotroph adenomas from patients with or without AIP mutation abundantly express GDNF, but AIP -mutated tissues have less CDKN2A-ARF expression. Our findings explain the tissue-specific mechanism of AIP-induced somatotrophinomas and provide a previously unknown tumorigenic mechanism, opening treatment avenues for AIP -related tumours

    Unmasking a new prognostic marker and therapeutic target from the GDNF-RET/PIT1/p14ARF/p53 pathway in acromegaly

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    Background: Acromegaly is produced by excess growth hormone secreted by a pituitary adenoma of somatotroph cells (ACRO). First-line therapy, surgery and adjuvant therapy with somatostatin analogs, fails in 25% of patients. There is no predictive factor of resistance to therapy. New therapies are investigated using few dispersed tumor cells in acute primary cultures in standard conditions where the cells do not grow, or using rat pituitary cell lines that do not maintain the full somatotroph phenotype. The RET/PIT1/p14ARF/p53 pathway regulates apoptosis in normal pituitary somatotrophs whereas the RET/GDNF pathway regulates survival, controlling PIT1 levels and blocking p14ARF (ARF) and p53 expression. Methods: We investigated these two RET pathways in a prospective series of 32 ACRO and 63 non-functioning pituitary adenomas (NFPA), studying quantitative RNA and protein gene expression for molecular-clinical correlations and how the RET pathway might be implicated in therapeutic success. Clinical data was collected during post-surgical follow-up. We also established new'humanized’ pituitary cultures, allowing 20 repeated passages and maintaining the pituitary secretory phenotype, and tested five multikinase inhibitors (TKI: Vandetanib, Lenvatinib, Sunitinib, Cabozantinib and Sorafenib) potentially able to act on the GDNF-induced RET dimerization/survival pathway. Antibody arrays investigated intracellular molecular pathways. Findings: In ACRO, there was specific enrichment of all genes in both RET pathways, especially GDNF. ARF and GFRA4 gene expression were found to be opposing predictors of response to first-line therapy. ARF cut-off levels, calculated categorizing by GNAS mutation, were predictive of good response (above) or resistance (below) to therapy months later. Sorafenib, through AMPK, blocked the GDNF/AKT survival action without altering the RET apoptotic pathway. Interpretation: Tumor ARF mRNA expression measured at the time of the surgery is a prognosis factor in acromegaly. The RET inhibitor, Sorafenib, is proposed as a potential treatment for resistant ACRO. Fund: This project was supported by national grants from Agencia Estatal de Investigación (AEI) and Instituto Investigación Carlos III, with participation of European FEDER funds, to IB (PI150056) and CVA (BFU2016-76973-R). It was also supported initially by a grant from the Investigator Initiated Research (IIR) Program (WI177773) and by a non-restricted Research Grant from Pfizer Foundation to IB. Some of the pituitary acromegaly samples were collected in the framework of the Spanish National Registry of Acromegaly (REMAH), partially supported by an unrestricted grant from Novartis to the Spanish Endocrine Association (SEEN). CVA is also supported from a grant of Medical Research Council UK MR/M018539/1

    Unmasking a new prognostic marker and therapeutic target from the GDNF-RET/PIT1/p14ARF/p53 pathway in acromegaly

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    Most of acromegaly is caused by a sporadic somatotropinoma and a couple of novel gene mutations responsible for somatotropinoma have recently been reported. To determine the cause of sporadic somatotropinoma in Japanese patients, we analyzed 61 consecutive Japanese patients with somatotropinoma without apparent family history. Comprehensive genetic analysis revealed that 31 patients harbored guanine nucleotide-binding protein, alpha stimulating (GNAS) mutations (50.8%) and three patients harbored aryl hydrocarbon receptor interacting protein (AIP) mutations (4.9%). No patients had G protein-coupled receptor 101 (GPR101) mutations. The patients in this cohort study were categorized into three groups of AIP, GNAS, and others and compared the clinical characteristics. The AIP group exhibited significantly younger age at diagnosis, larger tumor, and higher nadir GH during oral glucose tolerance test. In all patients with AIP mutation, macro- and invasive tumor was detected and repetitive surgery or postoperative medical therapy was needed. One case showed a refractory response to postoperative somatostatin analogue (SSA) but after the addition of cabergoline as combined therapy, serum IGF-I levels were controlled. The other case showed a modest response to SSA and the switching to cabergoline monotherapy was also effective. These data suggest that although resistance to SSA has been reported in patients with AIP mutations, the response to dopamine agonist (DA) may be retained. In conclusion, the cause of sporadic somatotropinoma in Japanese patients was comparable with the previous reports in Caucasians, patients with AIP mutations showed unique clinical characteristics, and DA may be a therapeutic option for patients with AIP mutations

    Effective and efficient polarity estimation in blogs based on sentence-level evidence

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    One of the core tasks in Opinion Mining consists of esti-mating the polarity of the opinionated documents found. In some scenarios (e.g. blogs), this estimation is severely af-fected by sentences that are off-topic or that simply do not express any opinion. In fact, the key sentiments in a blog post often appear in specific locations of the text. In this paper we propose several effective and robust polarity de-tection methods based on different sentence features. We show that we can successfully determine the polarity of doc-uments guided by a sentence-level analysis that takes into account topicality and the location in the blog post of the subjective sentences. Our experimental results show that some of our proposed variants are both highly effective and computationally-lightweight
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