2,555 research outputs found

    Application of a cost-benefit model to evaluate the investment viability of the small-scale cogeneration systems in the Portuguese context

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    Increasingly, modern society is dependent on energy to thrive. Remarkable attention is being drawn to high energy-efficient conversion systems such as cogeneration. World energy sustainability depends on the rational use of energy, fulfilling the demands without compromising the future of energy supply. The market trends foresee the use of decentralized production and the increasing replacement of conventional systems by small-scale cogeneration units as solutions to meet the energy needs of the building sector. Analysing the influence of the variables that determine the economic viability of decentralized energy production systems has become more important given the scenario of energy dependence and high energy costs for the final consumer. A cost-benefit model was developed and presented to identify the potential of small commercial scale cogeneration systems in the Portuguese building sector, based on cost-benefit analysis methodology. Five case-scenarios were analysed based on commercial models, using different technologies such as internal combustion engines, gas turbines and Stirling engines. A positive value of CBA analysis was obtained for all the tested cases, however, the use of classic economic evaluation criteria such as the net present value, internal rate of return and payback period results led to different investment decisions. The model also highlights the influence of energy prices in the economic viability of these energy power plants. The inclusion of subsidized tariffs for efficient energy production is the most contributing aspect in the analysis of the economic viability of small-scale cogeneration systems in the Portuguese building sector. Only in that case, it would be possible for an investor to recover the capital costs of such technology, even if the technical and societal benefits are accounted for

    Main neoplasic processes in psittacines birds kept in captivity

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    Um estudo anatomopatológico envolvendo 130 psitacídeos oriundos de centros de triagens, zoológicos e criadouros, visando a determinação da causa de morte destes animais, revelou a presença de neoplasias em sete animais, totalizando 5,4% dos casos. Os processos neoplasicos foram caracterizados como colangiocarcinoma, colangioma, linfoma, hemangiossarcoma e carcinoma renal primário, sendo o colangiocarcinoma o mais freqüentemente encontrado, presente em três animais. Este trabalho descreve estas neoplasias, levando em consideração os aspectos macro e microscópicos, meios de diagnósticos e espécies acometidas.An anatomopathologic study of 130 captivy psittacines from zoos, breeders and rehabilitation centers showed the presence of neoplastic disease in seven birds, totalizing 5.4% of the cases. The neoplasms were identified like cholangiocarcinoma, cholangioma, lymphoma, haemangiosarcoma and renal cell carcinoma. The cholangiocarcinoma was the tumor most commonly observed. it was present in birds. This study describes the macro and microscopic findings of these tumors; also reports diagnostic methods employed to identify these neoplasms.Fundação de Amparo à Pesquis

    Hermenêutica simbólica, Jung e transdiciplinariedade: luzes e sombras na educação

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    Este artigo de revisão e análise narrativa de literatura parte da perspectiva transdisciplinar com o objetivo de buscar alternativas epistêmico-metodológicas para que as pesquisas em educação desloquem-se da mera aquisição de conhecimentos à possibilidade de ampliação da consciência. O percurso narrativo do trabalho transita pelas interfaces dialógicas entre os pressupostos da transdisciplinariedade e os da hermenêutica simbólica do círculo de Eranos (HSCE). De forma inédita, alcança o objetivo no uso do conceito de unus mundus (Carl Gustav Jung) como ferramenta simbólica do fazer hermenêutico de transformação da realidade. No processo, via circularidade hermenêutica, múltiplas interfaces emergem a cada instância percorrida nas polaridades de luz e sombra, entre teorias e biografias

    Comparative Genome Analysis of Bacillus sporothermodurans with Its Closest Phylogenetic Neighbor, Bacillus oleronius, and Bacillus cereus and Bacillus subtilis Groups

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    Bacillus sporothermodurans currently possesses one of the most highly heat-resistant spores (HRS), which can withstand ultra-high temperature (UHT) processing. Determination of multiple whole genome sequences of B. sporothermodurans provided an opportunity to perform the first comparative genome analysis between strains and with B. oleronius, B. cereus, and B. subtilis groups. In this study, five whole genome sequences of B. sporothermodurans strains, including those belonging to the HRS clone (SAD and BR12) normally isolated from UHT milk, were compared with the aforementioned Bacillus species for gene clusters responsible for heat resistance. In the phylogenomic analysis, B. sporothermodurans, with its closest phylogenetic neighbor, B. oleronius, clustered with B. thermoamylovorans and B. thermotolerans. Heat shock proteins GrpE, GroES, GroEL, and DnaK presented identical sequences for all B. sporothermodurans strains, indicating that differences in functional efficiency are not involved in the thermal resistance variations. However, comparing all species evaluated, B. sporothermodurans exhibited a different gene configuration in the chromosomal region of the heat shock protein GrpE. Furthermore, only B. sporothermodurans strains presented the stage II sporulation protein P gene located in this region. Multisequence alignment and phylogenetic analysis of the ClpB protein showed differences for HRS and non-HRS strains. The study identified ClpC, ClpE, and ClpX as the three ATPases putatively involved in protein disaggregation in B. sporothermodurans. Bacillussporothermodurans exhibits high homology with other Bacillus species in the DnaK, DnaJ, GroEL, and GroES cluster of genes involved in heat resistance. The data presented here pave the way to select and evaluate the phenotypic effects of genes putatively involved in heat resistance

    Hypoxia impacts human MSC response to substrate stiffness during chondrogenic differentiation

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    Tissue engineering strategies often aim to direct tissue formation by mimicking conditions progenitor cells experience within native tissues. For example, to create cartilage in vitro, researchers often aim to replicate the biochemical and mechanical milieu cells experience during cartilage formation in the developing limb bud. This includes stimulating progenitors with TGF-β1/3, culturing under hypoxic conditions, and regulating mechanosensory pathways using biomaterials that control substrate stiffness and/or cell shape. However, as progenitors differentiate down the chondrogenic lineage, the pathways that regulate their responses to mechanotransduction, hypoxia and TGF-β may not act independently, but rather also impact one another, influencing overall cell response. Here, to better understand hypoxia's influence on mechanoregulatory-mediated chondrogenesis, we cultured human marrow stromal/mesenchymal stem cells (hMSC) on soft (0.167 kPa) or stiff (49.6 kPa) polyacrylamide hydrogels in chondrogenic medium containing TGF-β3. We then compared cell morphology, phosphorylated myosin light chain 2 staining, and chondrogenic gene expression under normoxic and hypoxic conditions, in the presence and absence of pharmacological inhibition of cytoskeletal tension. We show that on soft compared to stiff substrates, hypoxia prompts hMSC to adopt more spread morphologies, assemble in compact mesenchymal condensation-like colonies, and upregulate NCAM expression, and that inhibition of cytoskeletal tension negates hypoxia-mediated upregulation of molecular markers of chondrogenesis, including COL2A1 and SOX9. Taken together, our findings support a role for hypoxia in regulating hMSC morphology, cytoskeletal tension and chondrogenesis, and that hypoxia's effects are modulated, at least in part, by mechanosensitive pathways. Our insights into how hypoxia impacts mechanoregulation of chondrogenesis in hMSC may improve strategies to develop tissue engineered cartilage

    DESENVOLVIMENTO E VALIDAÇÃO DE UM DISPOSITIVO PARA MENSURAÇÃO DA FLEXIBILIDADE POR MEIO DO ACELERÔMETRO EM CRIANÇAS

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    The objectives of this study were to develop and validate a computerized device to measure joint flexibility; to measure flexibility in children in elementary school aged 8 to 10 years using the Wells bank; to compare the data obtained by the Wells bank and the computerized device developed in the present study and evaluate the usability of the device. 215 volunteers participated in this research, aged between 8 and 10 years, 63.72% (137) were female and 36.28% (78) were male, duly enrolled in an educational institution in the Alto Tietê region. For data collection, the volunteers performed the flexibility test using the Wells bank and the computerized device developed in this research to assess flexibility. The computerized device it was made on a 3D printing technology printer. A usability evaluation was carried out with 15 Physical Education teachers for the product developed through a usability questionnaire based on the System Usability Scale (SUS) form, which contains 10 multiple-choice questions. The data obtained by the objective measures determined were evaluated in terms of frequency, mean and standard deviation. The arithmetic means of the three measurements performed at each stage were calculated. Mann-Whitney and Kruskal-Wallis tests and Spearman's correlation were performed for the investigation. For all analyses, significant differences were considered p<0.05. It is concluded that the computerized device to measure joint flexibility is capable of evaluating the range of motion in degrees, and was qualified as easy to handle by professionals in the field of physical education.Los objetivos de este estudio fueron desarrollar y validar un dispositivo computarizado para medir la flexibilidad articular; medir la flexibilidad en niños en la escuela primaria de 8 a 10 años a través del banco Wells; comparar los datos obtenidos por la base de datos Wells y el dispositivo computarizado desarrollado en el presente estudio y evaluar la usabilidad del dispositivo. Un total de 215 voluntarios participaron en esta investigación, con edades de 8 a 10 años, 63,72% (137) mujeres y 36,28% (78) hombres, debidamente matriculados en una institución educativa de la región del Alto Tietê. Para la recolección de datos, los voluntarios realizaron la prueba de flexibilidad utilizando la base de datos Wells y el dispositivo computarizado desarrollado en esta investigación para evaluar la flexibilidad. El dispositivo fue hecho de una impresora de tecnología de impresión 3D. Se realizó una evaluación de usabilidad con 15 profesores de Educación Física para el producto desarrollado a través del cuestionario de usabilidad basado en el formulario System Usability Scale (SUS) que contiene 10 preguntas de opción múltiple. Los datos obtenidos por las mediciones objetivas determinadas fueron evaluados para la frecuencia, media y desviación estándar. Se calcularon las medias aritméticas de las tres mediciones realizadas en cada etapa. Las pruebas de Mann-Whitney y Kruskal-Wallis y la correlación de Spearman se realizaron para la investigación. Para todos los análisis, se consideraron diferencias significativas p<0,05. Se concluye que el dispositivo computarizado para medir la flexibilidad articular es capaz de evaluar el rango de movimiento en grados, y fue calificado fácil de manejar por profesionales de la educación física.Os objetivos deste estudo foram desenvolver e validar um dispositivo computadorizado para mensurar a flexibilidade articular; mensurar a flexibilidade em crianças no ensino fundamental de 8 a 10 anos por meio do banco de Wells; comparar os dados alcançados pelo banco de Wells e o dispositivo computadorizado desenvolvido no presente estudo e avaliar a usabilidade do dispositivo. Participaram desta pesquisa 215 voluntários, com idade de 8 a 10 anos, sendo 63,72% (137) do sexo feminino e 36,28% (78) do sexo masculino, devidamente matriculados em uma instituição de ensino na região do Alto Tietê. Para coleta de dados, os voluntários realizaram o teste de flexibilidade utilizando o banco de Wells e o dispositivo computadorizado desenvolvido nessa pesquisa para avaliar a flexibilidade.O dispositivo foi confeccionado numa impressora de tecnologia de impressão 3D. Foi realizada uma avaliação da usabilidade com 15 professores de Educação Física para o produto desenvolvido através da interação de usabilidade baseada no formulário System Sustainability Scale (SUS) que contém 10 questões de múltipla-escolha. Os dados obtidos por medidas objetivas determinadas foram avaliadas quanto à frequência, média e desvio padrão. Foram seguidas como médias aritméticas das três medidas realizadas em cada etapa. Para investigar realizou-se os testes de Mann-Whitney e de Kruskal-Wallis e a tradução de Spearman. Para todas as análises foram consideradas diferenças significativas p<0,05.Conclui-se que o dispositivo computadorizado para medir a flexibilidade articular é capaz de avaliar em graus a amplitude de movimento

    Incubation parameters, offspring growth, and behavioral adaptations to heat stress of Black Skimmers (Rynchops niger) in a Neotropical inland colony (Aves, Charadriiformes, Laridae)

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    This study focuses on incubation parameters, egg morphometrics, and body mass development, hatching, and behavioral adaptations to heat stress within a colony of freshwater-breeding Black Skimmers (Rynchops niger) located in the private nature reserve of Serviço Social do Comércio (SESC) in the northern Pantanal, Mato Grosso, Brazil. Temperatures of nest, eggs, and surface substratum, as well as the development of embryos, were surveyed using thermal imaging, a method allowing digital recording from a distance and in a fraction of the time of traditional measuring techniques. The mean egg dimensions (n = 71) were 4.48 (± 0.13) × 3.27 (± 0.07) cm; the mean mass at hatching was 24.3 (± 1.9) g, with a significant decrease over incubation time. The mean surface temperature of eggs varied from 30.9℃ to 39.7℃, while the sand surface temperature was 20℃ at 06:00 h, rising to 47.7℃ at 11:00 h. There was a significant increase (7%) in egg surface temperature throughout incubation. Incubation-bout durations (n = 2108) were correlated with the microclimatic conditions of the substratum, becoming shorter with increasing sand-surface temperature around midday. Egg hatching lasted one day, and siblings hatched no more than 24 h apart. The mean body mass on Day 1 after hatching was 16.8 (± 1.6) g (n = 6). Three days after hatching, chicks moved to new sand depressions provided by parents near the original nest, where they remained motionless or tried to hide under riparian vegetation. The single chick that fledged had a growth rate of K = 0.117 and a t₁₀₋₉₀ value of 37.3 days. On Day 7, dorsal pintail feathers and primaries appeared, which were open on Day 15. After 14 days, the chick was able to regulate its body temperature, and no more feeding by parental birds during the daytime was observed. On Day 21, the immature plumage was fully developed. Fledging was completed on Day 27. Our study demonstrates that thermal imaging is a useful method of surveying egg and embryo development in the Black Skimmer, reducing nest disturbance and observation efforts

    Short chain U(600) di-urea cross-linked poly(oxyethylene)/siloxane ormolytes doped with lanthanum triflate salt

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    Promising La3+-doped electrolytes based on a hybrid poly(oxyethylene)/siliceous host matrix, U(600), have been produced. The organic and inorganic components of the hybrid structure are covalently bonded through urea linkages. The low molecular weight of the polyether segments of U(600) is thought to be responsible for the total amorphous character and high conductivity at room temperature (1.1×10−4 S cm−1) of these ormolytes.Fundação para a Ciência e a Tecnologia (FCT

    Morphological and conductivity studies of di-ureasil xerogels containing lithium triflate

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    Sol–gel derived poly(oxyethylene)/siloxane hybrids doped with lithium triflate, LiCF3SO3, have been investigated. The host hybrid matrix of these materials, named di-ureasil and represented by U(600), is composed by a siliceous framework to which polyether chains containing 8.5 oxyethylene repeat units are covalently bonded through urea linkages. Xerogel samples U(600)nLiCF3SO3 with n (where n is the molar ratio of oxyethylene moieties per Li+ ion) between ∞ and 0.1 have been examined. X-ray diffraction and differential scanning calorimetry have provided conclusive evidence that the xerogels analyzed are entirely amorphous. The salt-rich material with n=1 exhibits the highest conductivity over the whole range of temperature analyzed (e.g. 4.3×10−6 and 2.0×10−4 Ω−1 cm−1, respectively, at 25 and 94 °C).Fundação para a Ciência e a Tecnologia (FCT

    Noonan syndrome: from phenotype to growth hormone therapy

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    A síndrome de Noonan (SN) é uma síndrome genética comum que constitui importante diagnóstico diferencial em pacientes com baixa estatura, atraso puberal ou criptorquidia. A SN apresenta grande variabilidade fenotípica e é caracterizada principalmente por dismorfismo facial, cardiopatia congênita e baixa estatura. A herança é autossômica dominante com penetrância completa. O diagnóstico é clínico, com base em critérios propostos por van der Burgt, em 1994. Recentemente, diversos genes envolvidos na via de sinalização RAS-MAPK foram identificados como causadores da SN: PTPN11, KRAS, SOS1, RAF1 e MEK1. O tratamento com hormônio de crescimento (hrGH) é proposto para corrigir a baixa estatura observada nestes pacientes. Estudos recentes apontam que pacientes com SN por mutações no gene PTPN11 apresentam pior resposta ao tratamento com hrGH quando comparado com pacientes sem mutações no PTPN11. Este artigo revisará os aspectos clínicos, moleculares e do tratamento da baixa estatura de crianças com SN com hrGH.Noonan Syndrome (NS) is one of the most common genetic syndromes and it is an important differential diagnosis in children with short stature, delayed puberty and cryptorchidism. NS is characterized by dysmorphic facial features, congenital heart defects and short stature, but there is a great variability in phenotype. NS may occur in a pattern consistent with autosomal dominant inheritance with almost complete penetrance. The diagnosis is based on a clinical score system proposed by van der Burgt e cols. in 1994. In recent years, germline mutations in the components of RAS-MAPK (mitogen activated protein kinase) pathway have been shown to be involved in the pathogenesis of NS. Mutations in PTPN11, KRAS, SOS1, RAF1 e MEK1 can explain 60-70% of NS molecular cause. Growth hormone therapy is proposed to correct the short stature observed in these patients. Recent studies suggest that the presence of PTPN11 mutations in patients with NS indicates a reduced growth response to short-term hrGH treatment. In this article, it is reviewed clinical and molecular aspects of NS and hrGH treatment for short stature.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
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