2,579 research outputs found
A 1.2-V 165-μW 0.29-mm² Multibit Sigma-Delta ADC for Hearing Aids Using Nonlinear DACs and With Over 91 dB Dynamic-Range
Genome-scale modeling of Chinese hamster ovary cells by hybrid semi-parametric flux balance analysis
Funding Information: This work was sponsored by GlaxoSmithKline Biologicals SA whereby the NOVA University Lisbon was engaged under an Agreement for R and D Services. All authors were involved in the conception and design of the study. PD’s lab performed the experiments/acquired the data. JR, GO, RO analyzed and interpreted the data. All authors were involved in drafting the manuscript or critically revising it for important intellectual content. All authors had full access to the data and approved the manuscript before it was submitted by the corresponding author. Publisher Copyright: © 2022, The Author(s).Flux balance analysis (FBA) is currently the standard method to compute metabolic fluxes in genome-scale networks. Several FBA extensions employing diverse objective functions and/or constraints have been published. Here we propose a hybrid semi-parametric FBA extension that combines mechanistic-level constraints (parametric) with empirical constraints (non-parametric) in the same linear program. A CHO dataset with 27 measured exchange fluxes obtained from 21 reactor experiments served to evaluate the method. The mechanistic constraints were deduced from a reduced CHO-K1 genome-scale network with 686 metabolites, 788 reactions and 210 degrees of freedom. The non-parametric constraints were obtained by principal component analysis of the flux dataset. The two types of constraints were integrated in the same linear program showing comparable computational cost to standard FBA. The hybrid FBA is shown to significantly improve the specific growth rate prediction under different constraints scenarios. A metabolically efficient cell growth feed targeting minimal byproducts accumulation was designed by hybrid FBA. It is concluded that integrating parametric and nonparametric constraints in the same linear program may be an efficient approach to reduce the solution space and to improve the predictive power of FBA methods when critical mechanistic information is missing.publishersversionpublishe
Digital Inclusion for Students with Attention Deficit Hyperactivity Disorder
The Attention Deficit Hyperactivity Disorder is a syndrome characterized by distraction, impulsivity, forgetfulness and disorganization. The diagnosis requires considerable care and experience. There are multiples approaches to treatments available, which can be used in combination to meet specific needs. In the academic field, virtual learning environment emerges as a watershed in the life and destiny of students who suffer from the disorder. The objective of this study is to promote digital inclusion for students with ADHD, through a virtual learning environment, in web platform, which will provide tools able to attract attention and stimulate interest in academic activities, aiming to generate significant changes in the process of student development
Recycling of Reinforced Glass Fibers Waste: Current Status
UID/00667/2020In this paper, a review of the current status and future perspectives for reinforced glass fiber waste is undertaken, as well as an evaluation of the management hierarchy for these end-of-life materials. Waste levels are expected to increase in the coming years, but an improvement of collection routes is still necessary. The recycling processes for these materials are presented. The associated advantages and disadvantages, as well as the corresponding mechanical characteristics, are described. Although mechanical shredding is currently the most used process, there is a potential for thermal processes to be more competitive than others due to the fiber quality after the recycling process. However, the energy requirements of each of the processes are not yet well explained, which compromises the determination of the economic value of the recycled fibers when included in other products, as well as the process feasibility. Nevertheless, the work of some authors that successfully integrated recycled glass fibers into other elements with increased mechanical properties is evaluated. Future recommendations for the recycling of glass fiber and its commercialization are made.publishersversionpublishe
Electromagnetic dual Einstein-Maxwell-scalar models
Electromagnetic duality is discussed in the context of
Einstein-Maxwell-scalar (EMS) models including axionic-type couplings. This
family of models introduces two non-minimal coupling functions and
, depending on a real scalar field . Interpreting the scalar
field as a medium, one naturally defines constitutive relations as in
relativistic non-linear electrodynamics. Requiring these constitutive relations
to be invariant under the electromagnetic duality rotations of
Maxwell's theory, defines 1-parameter, closed in the
space of EMS models, connecting different electromagnetic fields in "dual"
models with different coupling functions, but leaving both the scalar field and
the spacetime geometry invariant. This mapping works as a solution generating
technique, extending any given solution of a specific model to a (different)
solution for any of the dual models along the whole duality orbit. We
illustrate this technique by considering the duality orbits seeded by specific
EMS models wherein solitonic and black hole solutions are known. For dilatonic
models, specific rotations are equivalent to -duality.Comment: 18 pages, 1 figur
Algorithm of dynamic programming for optimization of the global matching between two contours defined by ordered points
This paper presents a new assignment algorithm with order restriction. Our optimization algorithm was developed using dynamic programming. It was implemented and tested to determine the best global matching that preserves the order of the points that define two contours to be matched. In the experimental tests done, we used the affinity matrix obtained via the method proposed by Shapiro, based on geometric modeling and modal matching. \newline The proposed algorithm revealed an optimum performance, when compared with classic assignment algorithms: Hungarian Method, Simplex for Flow Problems and LAPm. Indeed, the quality of the matching improved when compared with these three algorithms, due to the disappearance of crossed matching, which is allowed by the conventional assignment algorithms. Moreover, the computational cost of this algorithm is much lower than the ones of other three, leading to enhanced execution times
Optimization of the global matching between two contours defined by ordered points using an algorithm based on dynamic programming
This paper presents a new assignment algorithm with order restriction, developed using the paradigm of dynamic programming. The algorithm was implemented and tested to determine the best global matching between two sets of points that represent the contours to be matched. In the experimental tests done, we used the affinity matrix obtained via the method proposed by Shapiro based on geometric modeling and modal matching.The proposed algorithm revealed an optimum performance, when compared with the classic assignment algorithms considered in this work: Hungarian method, Simplex for Flow Problems and LAPm. Indeed, the quality of the matching improved when compared with these three algorithms, because the crossed matching, allowed by the conventional assignment algorithms, disappeared. Besides, the computational cost of our algorithm is very low in comparison with the other three, resulting in lesser execution times
Sex workers' narratives about clients with disabilities: can training improve sexual health in Portugal? = Narrativas de trabalhadores(as) do sexo sobre clientes com diversidade funcional: poderá a formação melhorar a saúde sexual em Portugal?
People with disabilities face barriers that limit their sexual lives. In Portugal, some individuals with physical impairments have shown interest in resorting to sexual assistance provided by trained professionals, according to the client’s preferences and needs. However, in Portugal, sex workers lacking any formal training represent the only way to access commercial sex services. Thus, this study analyzes the experiences of sex workers that provide services for disabled clients. The interviews of thirteen sex workers were analyzed using the thematic analysis method proposed by Braun and Clarke. The key findings show that men seek out sexual and emotional satisfaction from sex work. Additionally, specificities inherent to the lack of training and the relationships established tend to embarrass professionals. Finally, we conclude that training coupled with sexual education and popular awareness about gender differences in the pursuit of sex is fundamental to improve the sexual health of those who choose sex services as a way of sexual expression.info:eu-repo/semantics/publishedVersio
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