232 research outputs found
3D Topology Optimization of Spatially Reinforced Composites
Topology optimization is a numerical design tool used to generate structural concepts that present optimal load paths for a given set of functional requirements. This functional generative design capability has been used to lightweight high performance structures with 1D, 2D and 3D stress states. On the other hand, fiber-reinforced composites are the perfect candidate material to use in high performance structures due to the tailorability of their stiffness and strength properties. Although numerical tools that simultaneously tailor the composite material properties while optimizing the structural topology exist, these tools are inherently limited to 1D and 2D stress states.
This work aims to address this limitation by presenting a new topology optimization framework for 3D design of fiber-reinforced composites. Such computational design framework is composed of three key elements: (i) a macromechanical model, called multi-thread theory, that estimates the stiffness properties of 3D fiber reinforced composites; (ii) a stable coupling algorithm between macro-mechanics and structural analysis codes; and (iii) a scalable optimization algorithm.
To evaluate the feasibility of this framework, 2D and 3D topology optimization results are presented. The 2D numerical results are used to investigate the benefits of the new continuation scheme formulated within the optimization algorithm. Moreover, by optimizing 3D topologies with geometric conditions such that the stress state is approximately plane stress, the 2D results are used to show consistency between this computational design framework and other 2D approaches based on classical laminate theory. Finally, to demonstrate the capability of this framework a 3D MBB-beam is simultaneously optimized for both topology and fiber reinforcement orientation. This problem optimized 249,452 design variables to yield an optimized MBB 3D-beam that is 75% lighter, yet only 16.5% more flexible. Such step-change improvement in performance was due to the complex geometry of the optimized MBB 3D-beam (and its aligned reinforcement) involving structural elements such as curvilinear arches, variable-thickness sidewalls and uni-axial struts connecting these walls
BIOMedical search engine framework: lightweight and customized implementation of domain-specific biomedical search engines
The Smart Drug Search is publicly accessible at http://sing.ei.uvigo.es/sds/. The BIOMedical Search Engine Framework is freely available for non-commercial use at https://github.com/agjacome/biomsefBackground and Objectives: Text mining and semantic analysis approaches can be applied to the construction of biomedical domain-specific search engines and provide an attractive alternative to create personalized and enhanced search experiences. Therefore, this work introduces the new open-source BIOMedical Search Engine Framework for the fast and lightweight development of domain-specific search engines. The rationale behind this framework is to incorporate core features typically available in search engine frameworks with flexible and extensible technologies to retrieve biomedical documents, annotate meaningful domain concepts, and develop highly customized Web search interfaces.
Methods: The BIOMedical Search Engine Framework integrates taggers for major biomedical concepts, such as diseases, drugs, genes, proteins, compounds and organisms, and enables the use of domain-specific controlled vocabulary. Technologies from the Typesafe Reactive Platform, the AngularJS JavaScript framework and the Bootstrap HTML/CSS framework support the customization of the domain-oriented search application. Moreover, the RESTful API of the BIOMedical Search Engine Framework allows the integration of the search engine into existing systems or a complete web interface personalization.
Results
The construction of the Smart Drug Search is described as proof-of-concept of the BIOMedical Search Engine Framework. This public search engine catalogs scientific literature about antimicrobial resistance, microbial virulence and topics alike. The keyword-based queries of the users are transformed into concepts and search results are presented and ranked accordingly. The semantic graph view portraits all the concepts found in the results and the researcher may look into the relevance of different concepts, the strength of direct relations, and non-trivial, indirect relations. The number of occurrences of the concept shows its importance to the query, and the frequency of concept co-occurrence is indicative of biological relations meaningful to that particular scope of research. Conversely, indirect concept associations, i.e. concepts related by other intermediary concepts, can be useful to integrate information from different studies and look into non-trivial relations.
Conclusions
The BIOMedical Search Engine Framework supports the development of domain-specific search engines. The key strengths of the framework are modularity and extensibility in terms of software design, the use of open-source consolidated Web technologies, and the ability to integrate any number of biomedical text mining tools and information resources. Currently, the Smart Drug Search keeps over 1,186,000 documents, containing more than 11,854,000 annotations for 77,200 different concepts.This work was partially funded by the [14VI05] ContractProgramme from the University ofVigo and theAgrupamento INBIOMED from DXPCTSUG-FEDER unha maneira de facer Europa(2012/273).The research leading to these results has also received funding from the European Union Seventh Framework Programme FP7/REGPOT-2012-2013.1 under grant agreement n° 316265,BIOCAPS.This document reflects only the author’s views, and the European Union is not liable for any use that may be made of the information contained herei
Distância genética ente algumas variedades brasileiras de algodão medida por marcadores RAPDs.
bitstream/CNPA/19677/1/COMTEC254.pd
A retrospective analysis of oral and maxillofacial lesions in children and adolescents reported in two different services
Most epidemiological studies involving oral and maxillofacial lesions assess only data from histopathological analysis. This may lead to a poor notification of diseases whose diagnosis is predominantly clinical. Aim: To evaluate and to compare the freque
Uranyl complexes formed with apara-t-butylcalix[4]arene bearing phosphinoyl pendant arms on the lower rim. Solid and solution studies
The current interest in functionalized calixarenes with phosphorylated pendant arms resides in their coordination ability towards f elements and capability towards actinide/rare earth separation. Uranyl cation forms 1:1 and 1:2 (M:L) complexes with atetra-phosphinoylated p-tert-butylcalix[4]arene, B4bL4: UO2(NO3)2(B4bL4)n· xH2O (n = 1, x = 2, 1; n = 2, x = 6, 2). Spectroscopic data point to the inner coordination sphere of 1 containing one monodentate nitrate anion, one water molecule and the four phosphinoylated arms bound to UO22+ while in 2, uranyl is only coordinated to calixarene ligands. In both cases the U(VI) ion is 8-coordinate. Uranyl complexes display enhanced metal-centred luminescence due to energy transfer from the calixarene ligands; the luminescence decays are bi-exponential with associated lifetimes in the ranges 220μs <τs <250μs and 630μs <τL < 640μs, pointing to the presence of two species with differently coordinated calixarene, as substantiated by aXPS study of U(4f5/2,7/2), O(1s) and P(2p) levels on solid state samples. The extraction study of UO22+ cation and trivalent rare-earth (Y, La, Eu) ions from acidic nitrate media by B4bL4 in chloroform shows the uranyl cation being much more extracted than rare earth
Digital maturity and its determinants in General Practice: a cross- sectional study in 20 countries
Background: The extent to which digital technologies are employed to promote the delivery of high-quality healthcare is known as Digital Maturity. Individual and systemic digital maturity are both necessary to ensure a successful, scalable and sustainable digital transformation in healthcare. However, digital maturity in primary care has been scarcely evaluated. Objectives: This study assessed the digital maturity in General Practice (GP) globally and evaluated its association with participants' demographic characteristics, practice characteristics and features of Electronic Health Records (EHRs) use. Methods: GPs across 20 countries completed an online questionnaire between June and September 2020. Demographic data, practice characteristics, and features of EHRs use were collected. Digital maturity was evaluated through a framework based on usage, resources and abilities (divided in this study in its collective and individual components), interoperability, general evaluation methods and impact of digital technologies. Each dimension was rated as 1 or 0. The digital maturity score was calculated as the sum of the six dimensions and ranged between 0 to 6 (maximum digital maturity). Multivariable linear regression was used to model the total score, while multivariable logistic regression was used to model the probability of meeting each dimension of the score. Results: One thousand six hundred GPs (61% female, 68% Europeans) participated. GPs had a median digital maturity of 4 (P25–P75: 3–5). Positive associations with digital maturity were found with: male gender [B = 0.18 (95% CI 0.01; 0.36)], use of EHRs for longer periods [B = 0.45 (95% CI 0.35; 0.54)] and higher frequencies of access to EHRs [B = 0.33 (95% CI 0.17; 0.48)]. Practicing in a rural setting was negatively associated with digital maturity [B = −0.25 (95%CI −0.43; −0.08)]. Usage (90%) was the most acknowledged dimension while interoperability (47%) and use of best practice general evaluation methods (28%) were the least. Shorter durations of EHRs use were negatively associated with all digital maturity dimensions (aOR from 0.09 to 0.77). Conclusion: Our study demonstrated notable factors that impact digital maturity and exposed discrepancies in digital transformation across healthcare settings. It provides guidance for policymakers to develop more efficacious interventions to hasten the digital transformation of General Practice
Evaluation of two methods for computational HLA haplotypes inference using a real dataset
<p>Abstract</p> <p>Background</p> <p>HLA haplotype analysis has been used in population genetics and in the investigation of disease-susceptibility locus, due to its high polymorphism. Several methods for inferring haplotype genotypic data have been proposed, but it is unclear how accurate each of the methods is or which method is superior. The accuracy of two of the leading methods of computational haplotype inference – Expectation-Maximization algorithm based (implemented in Arlequin V3.0) and Bayesian algorithm based (implemented in PHASE V2.1.1) – was compared using a set of 122 HLA haplotypes (A-B-Cw-DQB1-DRB1) determined through direct counting. The accuracy was measured with the Mean Squared Error (<it>MSE</it>), Similarity Index (<it>I</it><sub><it>F</it></sub>) and Haplotype Identification Index (<it>I</it><sub><it>H</it></sub>).</p> <p>Results</p> <p>None of the methods inferred all of the known haplotypes and some differences were observed in the accuracy of the two methods in terms of both haplotype determination and haplotype frequencies estimation. Working with haplotypes composed by low polymorphic sites, present in more than one individual, increased the confidence in the assignment of haplotypes and in the estimation of the haplotype frequencies generated by both programs.</p> <p>Conclusion</p> <p>The PHASE v2.1.1 implemented method had the best overall performance both in haplotype construction and frequency calculation, although the differences between the two methods were insubstantial. To our knowledge this was the first work aiming to test statistical methods using real haplotypic data from the HLA region.</p
Evaluación de los modelos CMIP5 del IPCC en el Perú : proyecciones al año 2030 en la región Huánuco, reporte ejecutivo
El cambio climático es un hecho calificado por el IPCC (2007a) como “inequívoco”, y sus impactos son ya relevantes.
Según los resultados del Grupo de Trabajo II del Cuarto informe Científico AR4 del IPCC para América Latina (IPCC, 2007b), el Perú, como parte de la región andina tropical, es uno de los países que se verá más afectado por las consecuencias del cambio climático.
Para realizar estudios de impactos de los posibles cambios del clima en el futuro en la Región Huánuco, se requiere de modelos que simulan el sistema climático. Estos modelos requieren como entrada los escenarios futuros de emisiones de Gases de Efecto Invernadero, los que a su vez se basan en modelos socio-económicos globales.
En el presente estudio se ha considerado la evaluación de los últimos modelos globales CMIP5 del IPCC, con miras a implementar técnicas combinadas de regionalización en un futuro próximo para generar escenarios con mayor detalle para la Región Huánuco. El horizonte de evaluación corresponde al time-slice 2016-2045 centrado en el año 2030, bajo el contexto del nuevo escenario pesimista de altas emisiones RCP8.5, habiéndose considerado como período de línea de base climática 1971-2000
Epigenetic Landscape in Blood Leukocytes Following Ketosis and Weight Loss Induced by a Very Low Calorie Ketogenic Diet (VLCKD) in Patients With Obesity
[Abstract] Background:The molecular mechanisms underlying the potential health benefits of a ketogenic diet areunknown and could be mediated by epigenetic mechanisms.Objective:To identify the changes in the obesity-related methylome that are mediated by the inducedweight loss or are dependent on ketosis in subjects with obesity underwent a very-low calorie ketogenicdiet (VLCKD).Methods:Twenty-one patients with obesity (n¼12 women, 47.9±1.02 yr, 33.0±0.2 kg/m2) after 6months on a VLCKD and 12 normal weight volunteers (n¼6 women, 50.3±6.2 yrs, 22.7±1.5 kg/m2)were studied. Data from the Infinium MethylationEPIC BeadChip methylomes of blood leukocytes wereobtained at time points of ketotic phases (basal, maximum ketosis, and out of ketosis) during VLCKD(n¼10) and at baseline in volunteers (n¼12). Results were further validated by pyrosequencing inrepresentative cohort of patients on a VLCKD (n¼18) and correlated with gene expression.Results:After weight reduction by VLCKD, differences were found at 988 CpG sites (786 unique genes).The VLCKD altered methylation levels in patients with obesity had high resemblance with those fromnormal weight volunteers and was concomitant with a downregulation of DNA methyltransferases(DNMT)1, 3a and 3b. Most of the encoded genes were involved in metabolic processes, protein meta-bolism, and muscle, organ, and skeletal system development. Novel genes representing the top scoringassociated events were identified, includingZNF331,FGFRL1(VLCKD-induced weight loss) andCBFA2T3,C3orf38,JSRP1, andLRFN4(VLCKD-induced ketosis). Interestingly,ZNF331andFGFRL1were validated inan independent cohort and inversely correlated with gene expression.Conclusions:The beneficial effects of VLCKD therapy on obesity involve a methylome more suggestive ofnormal weight that could be mainly mediated by the VLCKD-induced ketosis rather than weight loss.This work was supported by the PronoKal Group® and grants from the Fondo de Investigacion Sanitaria as well as PI17/01287, PI20/00628 and PI20/00650 research projects and CIBERobn from the Instituto de Salud Carlos III (ISCIII)-Subdireccion General de Evaluacion y Fomento de la Investigación; Fondo Europeo de Desarrollo Regional (FEDER) Ana B Crujeiras is funded by a research contract “Miguel Servet” (CP17/00088) from the ISCIII, co-financed by the European Regional Development Fund (FEDER) and Xunta de Galicia-GAIN (IN607B2020)Xunta de Galicia; IN607B202
Seleção de isolados de rizóbio para nodulação de amendoim.
O processo de fixação de N atmosférico realizado pela simbiose entre plantas de 2 amendoim e bactérias do gênero Bradyrhizobium pode ser otimizado com a seleção de estirpes mais eficientes. Para verificar se existe variabilidade na capacidade de nodulação, foram isoladasbactériasa partirde nódulosde plantasde amendoim cultivadasno agreste paraibano. Para a inoculação, as bactérias foram cultivadas em meio líquido e transferidas para osolo, próximas à raizde cada Foram conduzidos dois ensaios. A eficiência da simbiose foi avaliada pelo número de nódulos e pelos pesos secos dos nódulos, da parte aérea e da raiz. Todas as plantas inoculadas apresentaram nódulos, o que não aconteceu com as não inoculadas. Isso demonstra que os isolados eram, realmente, rizóbios. O teste de Tukeymostrou, a 5% de probabilidade, que o número de nódulosdiferiu entre isolados e foi maior para os isolados EAV1. Este isolado, especialmente selecionado em uma planta muito produtiva, pode ser um bom candidato como estirpeeficiente. O estudo sugere quão importante é dar continuidade à seleção de estirpes e à integração ao programa de melhoramento do amendoim
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