Enzymatic hydrolysis of Cytisus striatus: acid sulfite pretreatment optimization

Ethanol production from lignocellulosic material includes three major steps: biomass pretreatment, which fragments the lignocellulosic matrix to facilitate the enzymes access to the substrate; hydrolysis, where the polysaccharides are converted into fermentable sugars (e.g. glucose and xylose) [1]; and finally, fermentation that produces ethanol or other biologically based chemicals (e.g. lactic acid, succinic acid) [2]. The aim was to study the effect of pretreatment operative variables, namely sodium bisulfite and sulfuric acid loadings, temperature and time, on released sugars in Cytisus striatus enzymatic hydrolysis with a Novozymes® cocktail. Pre-treatment intends lignin and hemicelluloses removal, reduced cellulose crystallinity and lignocellulosic network porosity increase in order to facilitate enzyme access.info:eu-repo/semantics/publishedVersio

Refining rheological response of chemical pulp fibre suspensions

The purpose of this work was to study the influence of the refining operating variables on the rheological response of chemical pulp fibre suspensions using a Valley beater. Pinus sylvestris, Eucalyptus globulus and Betula verrucosa bleached pulps were used. The normal and tangential average forces exerted on the pulp suspension in the gap clearance were evaluated, the gap between rotor and stator was measured and the apparent viscosity evolution during refining was obtained. The refining essays took place in a laboratory Valley beater, and the studied variables were the load on the roll, the rotor speed of rotation and the specific applied energy. Relationships between apparent viscosity and shear rate were tested for the three species fibre suspensions, which showed shear-thinning behaviour (Fig.1). The results were analysed in terms of fiber and flock properties. The computed crowding factors, Nc, (Kerekes and Schell) decrease from pine to eucalypt to birch. Thus, flock dimensions and resistance are significantly higher for pine. Pine had significantly wider gap, due to its greater and more resistant flocks. This produced smaller shear rate and thus higher apparent viscosity. The smaller and weaker eucalyptus and birch flocks induced smaller gaps, higher shear rates and smaller apparent viscosity. For each pulp suspension, the apparent viscosity diminished with refining time due to increased fibre flexibility and shortening, which promoted smaller flocks and reduced gap clearance (producing higher shear rates). The different rheological behaviors under the same operating conditions for different pulps lead to the inference that from the hydrodynamical point of view one should treat pulps with different morphological characteristics separately, considering the optimization of the energy transfer efficiency in pulp refining.info:eu-repo/semantics/publishedVersio

On the interplay between material flaws and dynamic necking

In this paper we investigate the interplay between material defects and flow localization in elastoplastic bars subjected to dynamic tension. For that task, we have developed a 10 finite difference scheme within a large deformation framework in which the material is modelled using rate-dependent J(2) plasticity. A perturbation of the initial yield stress is introduced in each node of the finite difference mesh to model localized material flaws. Numerical computations are carried out within a wide spectrum of strain rates ranging from 500 s(-1) to 2500 s(-1). On the one hand, our calculations reveal the effect of the material defects in the necking process. On the other hand, our results show that the necking inception, instead of being a random type process, is the deterministic result of the interplay between the mechanical behaviour of the material and the boundary conditions. This conclusion agrees with the experimental evidence reported by Rittel et al. [1] and Rotbaum et al. [2].The authors are indebted to the Ministerio de Economía y Competitividad de España (Project DPI2014-57989-P) for the financial support received which allowed conducting this work.Publicad

Elastoplastic solids subjected to dynamic tension: new experimental and computational insights

This Doctoral Thesis provides new insights into the mechanisms which control flow localization in elastoplastic solids subjected to dynamic tension. For that task, we have a developed a methodology which combines experiments and numerical calculations. Dynamic tension tests have been performed in a high-speed testing machine using specimens with six different gauge lengths, ranging from 20 �� to 140 ��, that have been tested within a wide spectrum of loading velocities from 1 �/� to 7.5 �/�. The experiments show that variations in the applied velocity and the gauge length of the samples lead to the systematic motion of the fracture location along the specimen. A key outcome is that we have provided experimental evidences of the deterministic nature of the flow localization in dynamic tensile specimens. Finite element calculations have been conducted in ABAQUS/Explicit in order to complement our experimental findings. The finite elements predict, in agreement with the experiments, the interplay between fracture location, impact velocity and gauge length. Moreover, we have explored the role played by initial and boundary conditions in plastic flow localization. A salient feature is that we have demonstrated that the intervention of stress waves within the specimen is a limiting factor for the sample ductility. On the one hand we have observed that the strain to failure, instead of being a material property, is strongly dependent on the specimen size. On the other hand, we have shown that the topology of the localization pattern is closely connected to the post-uniform elongation of the specimen. Finite difference calculations have been conducted in MATLAB in order to rationalize the experimental and finite element outcomes. For that task, we have developed a simple one-dimensional model within a finite deformation framework. The key point of our finite difference computations is that, unlike the finite element calculations, we solved the kinematics, and thus obtained a complete control of the problem. We show that the intervention of wave propagation phenomena within the specimen is responsible for the interplay between flow localization, impact velocity and gauge length. Moreover, we have explored the role of selected material properties in the kinetics of flow localization. A key outcome is that we have shown that material flaws (may) play a secondary role within the mechanisms which govern plastic localization in dynamic tensile specimens. All in all, we have developed a comprehensive and innovative research to establish: (1) the deterministic nature of flow localization and (2) the material properties and the initial and boundary conditions which control the process at handAgradecer al Ministerio de Ciencia e Innovación de España por el soporte financiero necesario para la consecución de este trabajo a través del proyecto DPI/2011-24068.Programa Oficial de Doctorado en Ingeniería Mecánica y de Organización IndustrialPresidente: José Fernández Sáez.- Secretario: Sebastián Mercier.- Vocal: Daniel Maurice Ritte

Células Stem mesenquimales en el transplante alogénico de progenitores hematopoyéticos: análisis de la experiencia clínica de la unidad de producción celular del Complejo Asistencial Universitario de Salamanca

[ES]El trasplante alogénico de progenitores hematopoyéticos (Alo-TPH) es un procedimiento utilizado con el objetivo de sustituir el tejido hematopoyético y el sistema inmune de un receptor que presenta una insuficiencia medular, una hemopatía maligna u otras alteraciones del sistema inmune (p. ej. inmunodeficiencias), empleando progenitores de médula ósea (MO), sangre periférica (SP) o cordón umbilical (SCU) de un donante sano, pudiendo ser emparentado (DE) o no emparentado (DnE). Recientemente se ha publicado la revisión del European Group for Blood and Marrow Transplantation (EBMT) sobre las indicaciones para la realización de trasplantes hematopoyéticos en adultos [1] . Describiremos en cuáles ha demostrado una superioridad estadísticamente significativa frente a otras estrategias terapéuticas sin trasplante. La principal indicación del alo-TPH es la leucemia aguda mieloblástica, siendo su realización favorable en las de intermedio y alto riesgo tras alcanzar la primera remisión completa o pacientes del grupo de riesgo favorable que fueron refractarios a un tratamiento de inducción con quimioterapia. En la leucemia aguda linfoblástica su indicación está establecida en los pacientes que presentan la t(9;21) o en las de alto riesgo en ausencia de esta traslocación, tras alcanzar la primera remisión completa. Así como, pacientes que han recaído tras quimioterapia que logran alcanzar una segunda remisión completa. En los síndromes mielodisplásicos el Alo-TPH aparece como una buena opción terapéutica si se realiza antes de la progresión de la enfermedad o en remisión completa tras quimioterapia o agentes hipometilantes. La decisión debe tomarse en función del riesgo de la enfermedad, del trasplante y del relacionado con el paciente. En los pacientes afectos por leucemia mieloide crónica está indicada la realización del trasplante en aquellos que están en fases avanzadas (especialmente crisis blástica) o en fase crónica multirresistente a inhibidores de tirosina quinasa. En el caso de la leucemia linfática crónica la introducción de fármacos inhibidores de vías de señalización ha cambiado el algoritmo terapéutico, siendo los pacientes candidatos a Alo-TPH los que no alcanzan respuesta con la quimioterapia estándar, ni a dichos fármacos. En mielofibrosis primaria se debe valorar el trasplante en los casos con DIPSS de intermedio II o alto riesgo. Los linfomas tienen la indicación favorable para la realización de un Alo-TPH cuando han padecido una recaída quimiosensible tras un trasplante autólogo (Auto-TPH), aunque la irrupción de las células CAR-T está modificando los algoritmos terapéuticos. En el mieloma múltiple el Alo-TPH es un tratamiento con potencial curativo, pero se asocia con una considerable mortalidad sin recaída, su uso podría usarse en pacientes seleccionados de alto riesgo, aunque de nuevo los CAR-T y los anticuerpos biespecíficos están modificando los consensos terapéuticos previos. Una indicación sin discusión es el caso de la aplasia medular grave de nuevo diagnóstico en pacientes jóvenes con donante emparentado HLA-idéntico

The power of self-love: an artificial neural network based on neuroscience inference to predict university students self-reported mental health dimensions

In line with the sustainable development goals of the United Nations 2030 agenda, namely goal number 3 – Good health and well-being -, student mental health is a global goal, first because it is health we are talking about and secondly because it has implications in the quality of learning and, consequently, in the adequate preparation of professionals for society. This study aimed to conduct an artificial neural network (ANN) to predict the student’s self-reported mental health dimensions. This is a cross-sectional and observational study enrolling data collected by applying a questionnaire comprising sociodemographic and health state variables from 2050 university students aged (18-30 years). The algorithm predicted the student’s overall mental health state self-perception with 94% accuracy (weighted average= [precision= 0.67%, recall= 0.67%, F-1 score0 0.67%]) and was cross-validated with reasonable accuracy (60%). The student’s depressive state was predicted with 97% accuracy (weighted average= [precision= 0.79%, recall=0.79%, F-1 score0 0.79%], and was cross-validated with good accuracy (73%). The student’s lack of interest in performing their activities of daily living (ADLs) was predicted with 94% accuracy (weighted average= [precision= 0.69%, recall=0.77%, F-1 score0 0.76%], and was cross-validated with reasonable accuracy (67%). The ANN presented excellent learning performance (>90%) for all targeted variables, within reasonable to good generalization capacity (60-73%). Finally, the university student’s depressive state was the best-predicted variable (73%).info:eu-repo/semantics/publishedVersio

The power of self-love: an artificial neural network based on neuroscience inference to predict university students self-reported mental health dimensions

Student mental health is a global goal, first because it is health we are talking about and secondly because it has implications in the quality of learning and, consequently, in the adequate preparation of professionals for society. The ANN presented excellent learning performance (> 90%) for all targeted variables, within reasonable to good generalization capacity (60-73%). Finally, the university student’s depressive state was the best-predicted variable (73%).info:eu-repo/semantics/publishedVersio

Failure behavior of 2024-T3 aluminum under tension-torsion conditions

Experimental and numerical investigations of the failure strain of aeronautical 2024-T3 aluminum were conducted. Experiments on the Double notched tube (DNT) specimen loaded in combined tension and torsion were applied to an aluminum alloy for the first time. Numerical analysis showed that the specimen exhibited uniformity in stress-strain as plastic strain developed. Low triaxiality values and a wide range of Lode parameter values were obtained at failure conditions. The failure strain of 2024-T3 aluminum showed strong dependence on the Lode parameter in agreement with the observations reported by other authors. The use of the DNT specimen was proven to be efficient in calibrating the ductile failure model of aluminum alloys.The researchers are indebted to the Ministerio de Ciencia e Innovación (DPI/2011-24068) for the financial support received, which enabled this work to be conducted

A eficácia de um programa de formulação de objectivos na performance e nas competências psicológicas, nos ensaios de uma tuna universitária – Monitorização dos ensaios e análise do PSIM

Dissertação de Mestrado apresentada ao ISPA - Instituto UniversitárioA formulação de objectivos implica aspectos como a eficácia da performance, o envolvimento e a participação do indivíduo (no nosso caso, do tuno), a competição no interior do grupo e o apoio do ensaiador. Este envolvimento é determinante para que o tuno sinta que tem um papel activo em todo o processo de formulação de objectivos. Os objectivos da performance prendem-se com o conseguir atingir padrões que se comparam com excelentes execuções anteriores, para os quais é necessário trabalhar a motivação, o controlo de ansiedade e a concentração, ou seja, a performance e as competências psicológicas surgem correlacionadas, na literatura revisitada. Uma Tuna Universitária consiste num grupo musical composto exclusivamente por alunos ou ex-alunos do ensino superior e que tem um papel importante na divulgação da cultura musical portuguesa. Este estudo é longitudinal e experimental, tendo sido realizado com 10 sujeitos masculinos. Pretendeu-se estudar o impacto de um Programa de Formulação de Objectivos na Performance (medida através de uma Base-Line) e nas Competências Psicológicas (medidas através de uma adaptação do PSIS) dos tunos da Estudantina Universitária de Lisboa, nomeadamente no que respeita aos seus ensaios, partindo-se do pressuposto de que seria positivo. Por outro lado, pretendeu-se verificar a existência de correlação entre a Performance e as Competências Psicológicas. Os resultados revelam que, para a maioria das dimensões de cada uma das variáveis, não existe correlação e que o impacto do Programa de Formulação de Objectivos foi reduzido, não se confirmando as nossas hipóteses para a maioria das dimensões.Goal-Setting implies aspects such as performance effectiveness, entanglement and participation of the individual (in our case, the tuno – an amateur musician), competition among the group and rehearser support. This entanglement is pivotal for the tuno to feel as an active part on all of the goal-setting process. Performance Objectives are binded to the accomplishment of patterns that can be compared with early high performances, for which it is needed to work motivation, anxiety control and concentration, ergo, performance and psychological skills come together correlated, in revisited literature. A Tuna Universitaria is a musical group formed exclusively by undergraduates or former undergraduates, having an important part on divulging portuguese musical culture. This study is longitudinal and experimental, having been made with 10 male individuals. We intended to study the influence of a Goal-Setting Program on Performance (measured through a Base-Line) and Psychological Skills (measured by an adaptation of the PSIS inventory) on the musicians (tunos) of the Estudantina Universitaria de Lisboa, moreover in what’s related to their rehearsals, postulating that it would be positive. On the other hand, we intended to verify the existence of a correlation between Performance and Psychological Skills. Results reveal, for a majority of dimensions of each variable, no correlation and the influence of the Goal-Setting Program was reduced, having no confirmation on our hypotheses, for most dimensions

Variáveis psicológicas associadas à performance no futebol Relação entre as perceções de competência, a ansiedade e o conhecimento tático de crianças e jovens

A excelência no contexto do futebol parece depender sobremaneira de um complexo sistema de variáveis interligadas, de entre as quais se destacam, entre outras, os fatores psicológicos relativos à perceção de competência (i.e., perceção de competência do desportista e perceção de competência refletida dos pais), a ansiedade e o conhecimento tático para se jogar. Face a esta constatação decidimos realizar dois estudos exploratórios. No primeiro estudo pretendeu-se saber que relações se estabelecem entre as perceções de competência e a ansiedade no futebol juvenil. Participaram no estudo 183 jovens praticantes de futebol do sexo masculino, com idades compreendidas entre os 11 e os 16 anos (14,2 ± 1,1). No segundo estudo pretendeu-se perceber que relação existia entre as perceções de competência, a ansiedade e o conhecimento tático no futebol juvenil. Neste estudo participaram 183 jovens praticantes de futebol do sexo masculino, com idades compreendidas entre os 11 e os 16 anos (14,2 ± 1,1). Para atingir os objetivos, recolheram-se informações relativamente à perceção de competência utilizando-se um questionário de cinco itens. No âmbito da perceção de competência refletida utilizou-se uma versão do Perceptions Mirroirs des Parents. Os dados sobre a ansiedade foram recolhidos através de uma versão da Sport Anxiety Scale - 2 e de uma Escala de Avaliação Cognitiva da Competição Perceção de Ameaça/Perceção de desafio Traço. Por fim, as informações relativas aos conhecimentos táticos foram obtidas através do questionário adaptado do Tactical Skills Inventory for Sports - TACSIS. Posteriormente, os dados foram analisados no SPSS, recorrendo ao tratamento estatísticos de correlação e regressão. Os resultados do primeiro estudo permitiram-nos concluir que a perceção de competência do desportista estava relacionada com baixos níveis de ansiedade. Já a partir dos resultados do segundo estudo, inferiu-se que a perceção de competência do desportista estava relacionada com melhores níveis de conhecimento tático do futebol. Concluímos que será importante que os diferentes agentes desportivos e os Psicólogos do Desporto promovam o feedback positivo enquanto ferramenta pedagógica de ensino, o reconhecimento de conquistas e facultem o suporte emocional necessário de modo a fortalecer a perceção de competência dos jogadores.Excellence in the context of soccer seems to depend heavily on a complex system of interconnected variables, including psychological factors relating to perceived competence (i.e. the sportsperson's perceived competence and the parents' reflected perception of competence), anxiety and tactical knowledge of how to play. Given this finding, we decided to carry out two exploratory studies. The first study aimed to find out what relationships exist between perceptions of competence and anxiety in youth soccer. 183 young male soccer players aged between 11 and 16 (14.2 ± 1.1) took part in the study. The second study aimed to understand the relationship between perceptions of competence, anxiety and tactical knowledge in youth soccer. This study involved 183 young male soccer players aged between 11 and 16 (14.2 ± 1.1). In order to achieve the objectives, information was collected on the perception of competence using a five-item questionnaire. As part of the perception of reflected competence, a version of the Parents' Perceptions Mirroirs was used. Data on anxiety was collected using a version of the Sport Anxiety Scale - 2 and a Cognitive Assessment of Competition Scale - Perception of Threat/Perception of Trait Challenge. Finally, information on tactical knowledge was obtained using a questionnaire adapted from the Tactical Skills Inventory for Sports - TACSIS. The data was then analyzed in SPSS, using correlation and regression statistics. The results of the first study allowed us to conclude that the sportsperson's perception of competence was related to low levels of anxiety. From the results of the second study, it was inferred that perceived competence was related to better levels of tactical knowledge of soccer. We conclude that it is important for sports agents and sports psychologists to promote positive feedback as a pedagogical teaching tool, to recognize achievements and to provide the necessary emotional support in order to strengthen players' perception of competence