Comparison of Two Common Maximum Power Point Trackers by Simulating of PV Generators

AbstractPower point tracker algorithms play an important role in the optimization of the power and the efficiency of a photovoltaic generator (PVG).We made the comparison between two algorithms currently implemented for the power optimization of PVG. These algorithms are based on the Perturb Observe and the Conductance-Increment methods allowing the Maximum Power Point Tracking, MPPT, principle. The study leads us to conclude that these algorithms are not well adapted for PVG exposures in very unfavorable but realistic external conditions

Salivary biomarkers for the diagnosis and monitoring of neurological diseases

Current research efforts on neurological diseases are focused on identifying novel disease biomarkers to aid in diagnosis, provide accurate prognostic information and monitor disease progression. With advances in detection and quantification methods in genomics, proteomics and metabolomics, saliva has emerged as a good source of samples for detection of disease biomarkers. Obtaining a sample of saliva offers multiple advantages over the currently tested biological fluids as it is a non-invasive, painless and simple procedure that does not require expert training or harbour undesirable side effects for the patients. Here, we review the existing literature on salivary biomarkers and examine their validity in diagnosing and monitoring neurodegenerative and neuropsychiatric disorders such as autism and Alzheimer\u27s, Parkinson\u27s and Huntington\u27s disease. Based on the available research, amyloid beta peptide, tau protein, lactoferrin, alpha-synuclein, DJ-1 protein, chromogranin A, huntingtin protein, DNA methylation disruptions, and micro-RNA profiles display a reliable degree of consistency and validity as disease biomarkers

Uma abordagem comparativa de algoritmos de aprendizado supervisionado para classificação dos cultivares da planta Paullinia cupana.

O guaranazeiro (Paullinia cupana) vem sendo estudado pela Embrapa Amazonia Ocidental desde o final da década de 70, resultando no desenvolvimento e disponibilizac¸ao de 19 cultivares resistentes as principais pragas e doenças. Contudo, a distinção dentre esses espécimes ainda é restrita a procedimentos manuais e técnicos, sujeitos à falha humana. Dessa forma, buscou-se identificar os melhores métodos de aprendizado supervisionado para o contexto de classificação desses cultivares a partir de imagens de suas folhas. Das técnicas utilizadas como Árvores de Decisao, Maquinas de Vetores de Suporte e Redes Neurais Convolucionais, essa última obteve melhor performance alcançando 89,6% de acurácia

Classificação de guaranazeiros através do padrão de venação e formato de folíolos utilizando aprendizagem de máquina.

O guaranazeiro é uma importante fonte de renda para estados amazônicos que o cultivam, porém sua produção é afetada devido à proliferação de pragas e doenças locais. Embrapa, então, lançou cultivares resistentes aos principais problemas que afetam a guaranaicultura na Amazônia, mas o processo de identificação desses cultivares são manuais, custosos e carente de recursos humanos. Assim, este trabalho buscou comparar técnicas de aprendizagem de máquinas como Florestas Aleatórias, Máquinas de Vetores de Suporte e Redes Perceptron aplicadas à tarefa de classificação desses cultivares, através do padrão da nervura e formato dos folíolos. Os resultados apresentam-se estáveis e satisfatórios, sugerindo uma nova perspectiva para o problema em questão

Chaperone holdase activity of human papillomavirus E7 oncoprotein

E7 oncoprotein is the major transforming activity in human papillomavirus and shares sequence and functional properties with adenovirus E1A and SV40 T-antigen, in particular by targeting the pRb tumor suppressor. HPV 16 E7 forms spherical oligomers that display chaperone activity in thermal denaturation and chemical refolding assays of two model polypeptide substrates, citrate synthase and luciferase, and it does so at substoichiometric concentrations. We show that the E7 chaperone can stably bind model polypeptides and hold them in a state with significant tertiary structure, but does not bind the fully native proteins. The E7 oligomers bind native in vitro translated pRb without the requirement of it being unfolded, since the N-terminal domain of E7 containing the LXCXE binding motif is exposed. The N-terminal domain of E7 can interfere with pRb binding but not with the chaperone activity, which requires the C-terminal domain, as in most reported E7 activities. The ability to bind up to ∼72 molecules of pRb by the oligomeric E7 form could be important either for sequestering pRb from Rb-E2F complexes or for targeting it for proteasome degradation. Thus, both the dimeric and oligomeric chaperone forms of E7 can bind Rb and various potential targets. We do not know at present if the chaperone activity of E7 plays an essential role in the viral life cycle; however, a chaperone activity may explain the large number of cellular targets reported for this oncoprotein.Fil: Alonso, Leonardo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Smal, Clara. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Garcia Alai, Maria M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Chemes, Lucia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Salame, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: de Prat Gay, Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentin

A Combination of Approved Antibodies Overcomes Resistance of Lung Cancer to Osimertinib by Blocking Bypass Pathways.

<b>Purpose:</b> Because of emergence of resistance to osimertinib, a third-generation EGFR tyrosine kinase inhibitor (TKI), no targeted treatments are available for patients with lung cancer who lose sensitivity due to new mutations or bypass mechanisms. We examined in animals and <i>in vitro</i> an alternative therapeutic approach making use of antibodies. <b>Experimental Design:</b> An osimertinib-sensitive animal model of lung cancer, which rapidly develops drug resistance, has been employed. To overcome compensatory hyperactivation of ERK, which we previously reported, an anti-EGFR antibody (cetuximab) was combined with other antibodies, as well as with a subtherapeutic dose of osimertinib, and cancer cell apoptosis was assayed. <b>Results:</b> Our animal studies identified a combination of three clinically approved drugs, cetuximab, trastuzumab (an anti-HER2 mAb), and osimertinib (low dose), as an effective and long-lasting treatment that is able to prevent onset of resistance to osimertinib. A continuous schedule of concurrent treatment was sufficient for effective tumor inhibition and for prevention of relapses. Studies employing cultured cells and analyses of tumor extracts indicated that the combination of two mAbs and a subtherapeutic TKI dose sorted EGFR and HER2 for degradation; cooperatively enhanced apoptosis; inhibited activation of ERK; and reduced abundance of several bypass proteins, namely MET, AXL, and HER3. <b>Conclusions:</b> Our <i>in vitro</i> assays and animal studies identified an effective combination of clinically approved drugs that might overcome resistance to irreversible TKIs in clinical settings. The results we present attribute the long-lasting effect of the drug combination to simultaneous blockade of several well-characterized mechanisms of drug resistance. <i>Clin Cancer Res; 24(22); 5610-21. ©2018 AACR</i> <i>See related commentary by Fan and Yu, p. 5499</i>

The effect of reverse current on the dark properties of photovoltaic solar modules

AbstractForward and reverse dark current-voltage (I-V) and capacitance-voltage (C-V) characteristics of commercial amorphous silicon solar modules, were measured in order to study their performance under the influence of induced reverse currents. Maximum module surface temperatures were directly related to each value of the induced reverse current and in to the amount of current leakage respectively. Microscopic changes as a result of hot spots defects and overheating of the solar module, linked to reverse current effects, were also documented and discussed. Experimental evidence showed that different levels of reverse currents are confirmed to be a major degrading factor affecting the performance, efficiency, and power of solar modules

Aplicativo móvel para recomendação de adubação e calagem para produção de mandioca no Amazonas.

Em decorrência da necessidade de elevar a produção de mandioca no Amazonas e ao difícil acesso dos produtores rurais às informações de manejo e cultivo, foi proposto e desenvolvido um aplicativo para smartphone com a plataforma Android, que tem como objetivo fornecer recomendação de adubação e calagem para correção do solo a partir do resultado da análise química realizada. Fornece ainda dicas práticas para manejo e cultivo da mandioca e ferramentas de cálculos e conversões necessárias para um bom planejamento e execução para um plantio de qualidade