679 research outputs found

    Recent Progress and Trends in the Development of Microbial Biofuels from Solid Waste—A Review

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    This review covers the recent progress in the design and application of microbial biofuels, assessing the advancement of genetic engineering undertakings and their marketability, and lignocellulosic biomass pretreatment issues. Municipal solid waste (MSW) is a promising sustainable biofuel feedstock due to its high content of lignocellulosic fiber. In this review, we compared the production of fatty alcohols, alkanes, and n-butanol from residual biogenic waste and the environmental/economic parameters to that of conventional biofuels. New synthetic biology tools can be used to engineer fermentation pathways within micro-organisms to produce long-chain alcohols, isoprenoids, long-chain fatty acids, and esters, along with alkanes, as substitutes to petroleum-derived fuels. Biotechnological advances have struggled to address problems with bioethanol, such as lower energy density compared to gasoline and high corrosive and hygroscopic qualities that restrict its application in present infrastructure. Biofuels derived from the organic fraction of municipal solid waste (OFMSW) may have less environmental impacts compared to traditional fuel production, with the added benefit of lower production costs. Unfortunately, current advanced biofuel production suffers low production rates, which hinders commercial scaling-up efforts. Microbial-produced biofuels can address low productivity while increasing the spectrum of produced bioenergy molecules

    Immunity related genes in dipterans share common enrichment of AT-rich motifs in their 5' regulatory regions that are potentially involved in nucleosome formation

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    <p>Abstract</p> <p>Background</p> <p>Understanding the transcriptional regulation mechanisms in response to environmental challenges is of fundamental importance in biology. Transcription factors associated to response elements and the chromatin structure had proven to play important roles in gene expression regulation. We have analyzed promoter regions of dipteran genes induced in response to immune challenge, in search for particular sequence patterns involved in their transcriptional regulation.</p> <p>Results</p> <p>5' upstream regions of <it>D. melanogaster </it>and <it>A. gambiae </it>immunity-induced genes and their corresponding orthologous genes in 11 non-melanogaster drosophilid species and <it>Ae. aegypti </it>share enrichment in AT-rich short motifs. AT-rich motifs are associated with nucleosome formation as predicted by two different algorithms. In <it>A. gambiae </it>and <it>D. melanogaster</it>, many immunity genes 5' upstream sequences also showed NFκB response elements, located within 500 bp from the transcription start site. In <it>A. gambiae</it>, the frequency of ATAA motif near the NFκB response elements was increased, suggesting a functional link between nucleosome formation/remodelling and NFκB regulation of transcription.</p> <p>Conclusion</p> <p>AT-rich motif enrichment in 5' upstream sequences in <it>A. gambiae, Ae. aegypti </it>and the <it>Drosophila </it>genus immunity genes suggests a particular pattern of nucleosome formation/chromatin organization. The co-occurrence of such motifs with the NFκB response elements suggests that these sequence signatures may be functionally involved in transcriptional activation during dipteran immune response. AT-rich motif enrichment in regulatory regions in this group of co-regulated genes could represent an evolutionary constrained signature in dipterans and perhaps other distantly species.</p

    Factores domiciliarios asociados con la presencia de hidatidosis humana en tres comunidades rurales de Junín, Perú

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    Introduction. Hydatid disease, a zoonosis caused by the larval stage of the parasite Echinococcus granulosus, is a public health problem at national level, especially in those regions dedicated to raising livestock. By now, there are many factors, at individual level, that have been associated to the infection by E. granulosus; nevertheless there is not any previous report that explore the association between household characteristics and the presence of the disease among household members. Objective. To explore the association between household characteristics and the presence of hydatid disease among household members. Material and methods. We performed a cross-sectional study in the households of 3 rural communities located in Junín, we evaluated the association between household characteristics and the presence of hydatid disease by multiple logistic regression (MLR). Results. from 417 evaluated households, 56 (13%) of them had at least one positive case among its members. Multivariate analysis showed that households with three or more members, located in the community with the lowest quintile of poverty, that reported raising livestock, and with evaluation coverage greater than 25% were more likely to have at least one positive case among its members. Conclusion. The observed characteristics be taken into account in the preliminary definition of high-risk subgroups, optimizing the use of resources and improving the effectiveness of screening programs. Introducción. La hidatidosis, zoonosis producida por el estadio larvario de la taenia Echinococcus granulosus, es un problema de salud pública a nivel nacional, en especial en aquellas regiones dedicadas a la crianza de ganado. A la fecha, se han descrito factores, a nivel individual, asociados con la infección por E. granulosus; sin embargo, no se encontró reporte previo que explore la asociación entre características de la vivienda y la presencia de esta enfermedad en alguno de sus miembros. Objetivos. Explorar la asociación entre las características de la vivienda y la presencia de hidatidosis entre las personas que la habitan. Materiales y métodos. Se realizó un estudio transversal en viviendas de tres comunidades rurales de Junín. Se evaluó el grado de asociación entre las características de la vivienda y la presencia de hidatidosis en el hogar mediante un análisis de regresión logística múltiple (RLM). Resultados. De un total de 417 viviendas evaluadas, 56 (13%) de ellas tenían al menos un caso positivo entre sus miembros; luego del análisis de RLM se observó que aquellas viviendas con más de tres miembros, localizadas en la comunidad con quintil de pobreza más bajo, que refirieron crianza de animales, y con una cobertura de evaluación mayor al 25% presentaron una mayor probabilidad de tener al menos un caso de positivo entre sus miembros. Conclusión. Las características observadas deben ser tomadas en cuenta para la determinación preliminar de subgrupos de alto riesgo, optimizando así el uso de los recursos y mejorando la eficacia de los programas de despistaje

    The Entropy of the Rotating Charged Black Threebrane from a Brane-Antibrane System

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    We show that a model based on a D3-brane--anti-D3-brane system at finite temperature, proposed previously as a microscopic description of the non-rotating black threebrane of type IIB supergravity arbitrarily far from extremality, can also successfully reproduce the entropy of the rotating threebrane with arbitrary charge (including the neutral case, which corresponds to the Kerr black hole in seven dimensions). Our results appear to confirm in particular the need for a peculiar condition on the energy of the two gases involved in the model, whose physical interpretation remains to be elucidated.Comment: 12 pages, references added in section 1 and

    Quality appraisal of clinical guidelines for recurrent urinary tract infections using AGREE II:a systematic review

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    INTRODUCTION AND HYPOTHESIS: Recommendations for preventing and diagnosing recurrent urinary tract infection (UTI) tend to vary between clinical practice guidelines (CPGs) because of low-quality scientific evidence, potentially leading to practice variation and suboptimal care. We assessed the quality of existing CPGs for recurrent UTI. METHODS: A systematic search was performed from January 2000 to June 2021 in PubMed and EMBASE for CPGs on recurrent UTI prevention or hospital diagnostics in Dutch, English, and Spanish. Each CPG was assessed by four appraisers in a multidisciplinary review team, using the Appraisal of Guidelines, Research, and Evaluation II (AGREE II) instrument. RESULTS: We identified and assessed eight CPGs published between 2013 and 2021. The scope and purpose (mean and standard deviation: 67.3 ± 21.8) and clarity of presentation (74.8 ± 17.6) domains scored highly. However, issues with methods, patient participation, conflict of interests, and facilitators and barriers were common and resulted in lower scores for the rigour of development (56.9 ± 25.9), applicability (19.6 ± 23.4), stakeholder involvement (50.4 ± 24.6), and editorial independence (62.1 ± 23.1) domains. Overall, two CPGs were recommended, three were recommended with modifications, and three were not recommended. CONCLUSIONS: Significant room for improvement exists in the quality of CPGs for recurrent UTI, with most displaying serious limitations in the stakeholder involvement, rigour of development, and applicability domains. These aspects must be improved to decrease diagnostic and therapeutic uncertainty. Developers could benefit from using checklists and following guidelines when developing de novo CPGs

    Validación de la Escala Breve de Optimismo Interactivo-G en México antes de la COVID-19

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    The primary objectives of this study were determining the construct, convergent, and discriminant validity of the Brief Interactive Optimism Scale-G (BIOS-G) in participants from six states of Mexico and estimating its internal consistency. In this study 3 289 Mexicans participated (2 028 men and 1 243 women). The average age was = 30.43 years and SD = 10.52. Confirmatory factor analysis (CFA) and multiple regression analysis (MRA) were applied. There were appropriate fit indexes (e. g., CFI = .99; RMSEA = .07.). Convergent validity showed ANR (3 289)=.52(p=&lt;.01;d=medium), with the Satisfaction with Life Scale (SWLS) and the estimation of discriminant validity was r (3 289) r = -.19 with the Brief Scale for Assessing Anger Proneness (APS-G) (p = &lt; .01; d = almost small), Alpha = .70 (3 289); p = &lt; .01; omega = .76. The conclusion is that there is partial national evidence supporting the use of BIOS-G, because Mexico lacks a measure of this kind, being useful, at least, for research purposes.Los objetivos primarios del presente estudio fueron determinar la validez de constructo, convergente y discriminante de la Escala Breve de Optimismo Interactivo-G (EBOI-G), en participantes de seis estados de México y calcular su consistencia interna. Participaron 3289 mexicanos, 2028 hombres y 1243 mujeres (18 casos no contestaron cuál era su género). Su edad promedio = 30.43 años, de = 10.52. Se usó el análisis factorial confirmatorio y análisis de regresión múltiple, y se encontraron buenos indicadores promedio de bondad de ajuste (e. g., CFI = .99; RMSEA = .07.). Se evaluó la validez convergente, r (3 289) = .52 (p = &lt; .01; d = mediano), con la Escala de Satisfacción con la Vida. Se estimó la validez discriminante, r (3 289) r = -.19, con la Escala Breve de Disposición a la IRA (p = &lt; .01; d = casi pequeño). El alfa = .70 (3 289); p = &lt; .01; el omega = .76. Se concluye que hay evidencia parcial nacional que apoya el uso de la EBOI-G, debido a la carencia de una medida de este tipo en México, útil cuando menos para propósitos de investigación.Os objetivos primários do estudo foram determinar a validade convergente e discriminante do construto da Escala Breve de Otimismo Interativo-G (EBOI-G), em participantes de seis estados do México e calcular sua consistência interna. Participaram 3 289 mexicanos, sendo 2 028 homens e 1 243 mulheres. A média de idade foi = 30.43 anos, DP = 10.52. Foram utilizadas análises fatoriais confirmatórias e análises de regressão múltipla. Bons indicadores médios de qualidade de ajuste foram encontrados (por exemplo, CFI = .99; RMSEA = .07.) A validade convergente foi avaliada, r (3 289) = .52 (p = &lt;.01; d = mediana), com a Escala de satisfação com a vida. A validade discriminante, r (3 289) = -.19 foi estimada com a Escala Breve de Disposição à Raiva (p = &lt;.01; d = quase pequeno). O alfa = 0,70 (3 289); p = &lt;0,01; o ômega = 0,76. Conclui-se que há evidências nacionais parciais que apoiam o uso da EBOI-G, devido à falta de uma medida desse tipo no México, sendo útil pelo menos para fins de pesquisa

    Multiphysics simulation of a microfluidic perfusion chamber for brain slice physiology

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    Understanding and optimizing fluid flows through in vitro microfluidic perfusion systems is essential in mimicking in vivo conditions for biological research. In a previous study a microfluidic brain slice device (μBSD) was developed for microscale electrophysiology investigations. The device consisted of a standard perfusion chamber bonded to a polydimethylsiloxane (PDMS) microchannel substrate. Our objective in this study is to characterize the flows through the μBSD by using multiphysics simulations of injections into a pourous matrix to identify optimal spacing of ports. Three-dimensional computational fluid dynamic (CFD) simulations are performed with CFD-ACE + software to model, simulate, and assess the transport of soluble factors through the perfusion bath, the microchannels, and a material that mimics the porosity, permeability and tortuosity of brain tissue. Additionally, experimental soluble factor transport through a brain slice is predicted by and compared to simulated fluid flow in a volume that represents a porous matrix material. The computational results are validated with fluorescent dye experiments
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