Incorporation Of Nanocrystals With Different Dimensionalities In Hybrid Tio2/p3ht Solar Cells

We investigate the effect of TiO2 nanoparticles-nanospheres and nanorods-inserted in the poly(3-hexylthiophene) (P3HT) matrix of TiO2?P3HT inverted hybrid solar cells. X-ray diffraction, high-resolution transmission electron microscopy, small-angle x-ray scattering, photoluminescence, and photoelectrochemical experiments were employed to investigate the structure, morphology, and photoactivity of TiO2 nanoparticles modified with 2-thiopheneacetic acid, mixed or not with P3HT. Both TiO2 nanospheres and TiO2 nanorods presented a good dispersion in the polymer matrix. The incorporation of TiO2 nanospheres and nanorods has improved the photocurrent generation, and devices with efficiency values up to 1.35% were obtained. Our results reveal that the nanoscale morphology enables an enhanced interfacial area for exciton dissociation. 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CURSO DE FORMAÇÃO PEDAGÓGICA PARA MONITORES DA UFAPE: CONTRIBUIÇÕES ACADÊMICAS E PROFISSIONAIS

Nesse artigo a partir da experiência vivenciada no projeto de ensino coordenado pela Comissão de Ensino, em parceria com a Coordenação Geral de Cursos de Graduação, da Unidade Acadêmica de Garanhuns (UFRPE), atual Universidade Federal do Agreste de Pernambuco - UFAPE, em 2019, analisam-se as contribuições do curso para formação dos monitores para a formação acadêmica e profissional dos estudantes participantes do evento. Adota como fundamentação teórica os estudos de Lee Shulman que investigam conhecimentos necessários para o ensino. Os dados foram coletados por meio de um formulário on-line composto, em sua maior parte, por perguntas que deveriam ser respondidas atribuindo pontuação de 1 a 5, utilizando a escala de Likert. O perfil dos participantes foi diversificado, incluindo discentes ligados aos programas de monitoria e tutoria bolsistas ou voluntários. As motivações, indicadas pelos discentes participantes do curso, para ingresso nos programas de monitoria ou tutoria estão alinhadas com as definidas na resolução UFRPE 262/2001. Os participantes citaram positivamente a relação dos temas tratados com as atividades práticas da monitoria destacando-se o estímulo à profissão docente, especialmente ao contribuir para o desenvolvimento de conhecimentos pedagógicos, sobre avaliação; aprendizagem; metodologias de ensino, entre outros, importantes aspectos para a profissionalização docente

Economic analysis of an agrosilvipastoral system for a mountainous area in Zona da Mata Mineira, Brazil

The objective of this work was to evaluate the economic viability of an agrosilvipastoral system developed for Zona da Mata mountainous areas in Minas Gerais state, Brazil, as well as to compare different options for wood (Eucalyptus grandis and Acacia mangium) commercialization of the second thinning. The data were obtained from a 10 year-old agrosilvipastoral system established in four hectares at Embrapa Gado de Leite station in Coronel Pacheco, MG, Brazil. As evaluation criteria for the economic viability analysis, the adopted methods were the net present value (NPV) and the internal rate of return (IRR), both calculated at 6% interest rate. Despite the small difference, adding value to forest products increased the attractiveness of the proposed system. Considered separately, the agricultural activity was impracticable, whereas the forestry and livestock activities were independently viable. The studied system seems to be equally tolerant to price variations for forest and livestock products, as well as strongly tolerant to variations in production costs

Correction of Basic Equations for Deep Bed Filtration with Dispersion

Copyright © 2006 Elsevier B.V. All rights reserved.Deep bed filtration of particle suspensions in porous media occurs during water injection into oil reservoirs, drilling fluid invasion into reservoir productive zones, fines migration in oil fields, bacteria, virus or contaminant transport in groundwater, industrial filtering, etc. The basic features of the process are advective and dispersive particle transport and particle capture by the porous medium. Particle transport in porous media is determined by advective flow of carrier water and by hydrodynamic dispersion in micro-heterogeneous media. Thus, the particle flux is the sum of advective and dispersive fluxes. Transport of particles in porous media is described by an advection–diffusion equation and by a kinetic equation of particle capture. Conventional models for deep bed filtration take into account hydrodynamic particle dispersion in the mass balance equation but do not consider the effect of dispersive flux on retention kinetics. In the present study, a model for deep bed filtration with particle size exclusion taking into account particle hydrodynamic dispersion in both mass balance and retention kinetics equations is proposed. Analytical solutions are obtained for flows in infinite and semi-infinite reservoirs and in finite porous columns. The physical interpretation of the steady-state flow regimes described by the proposed and the traditional models favours the former.Altoe, J. E., Bedrikovetski, P.G., Siqueira, A. G., de Souza, A. L., Shecaira, F.http://www.elsevier.com/wps/find/journaldescription.cws_home/503345/description#descriptio

C9ORF72 patient-derived endothelial cells drive blood-brain barrier disruption and contribute to neurotoxicity

The blood-brain barrier (BBB) serves as a highly intricate and dynamic interface connecting the brain and the bloodstream, playing a vital role in maintaining brain homeostasis. BBB dysfunction has been associated with multiple neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS); however, the role of the BBB in neurodegeneration is understudied. We developed an ALS patient-derived model of the BBB by using cells derived from 5 patient donors carrying C9ORF72 mutations. Brain microvascular endothelial-like cells (BMEC-like cells) derived from C9ORF72-ALS patients showed altered gene expression, compromised barrier integrity, and increased P-glycoprotein transporter activity. In addition, mitochondrial metabolic tests demonstrated that C9ORF72-ALS BMECs display a significant decrease in basal glycolysis accompanied by increased basal and ATP-linked respiration. Moreover, our study reveals that C9-ALS derived astrocytes can further affect BMECs function and affect the expression of the glucose transporter Glut-1. Finally, C9ORF72 patient-derived BMECs form leaky barriers through a cell-autonomous mechanism and have neurotoxic properties towards motor neurons