Ultra-High-Energy Cosmic Ray Acceleration by Magnetic Reconnection in Newborn Accretion Induced Collapse Pulsars

We here investigate the possibility that the ultra-high energy cosmic ray (UHECR) events observed above the GZK limit are mostly protons accelerated in reconnection sites just above the magnetosphere of newborn millisecond pulsars which are originated by accretion induced collapse (AIC). We show that AIC-pulsars with surface magnetic fields $10^{12} G < B_{\star} \lesssim 10^{15}$ G and spin periods $1 ms \lesssim P_{\star} < 60 ms$, are able to accelerate particles to energies $\geq 10^{20}$ eV. Because the expected rate of AIC sources in our Galaxy is very small (\sim 10^{-5} yr^{-1}), the corresponding contribution to the flux of UHECRs is neglegible, and the total flux is given by the integrated contribution from AIC sources produced by the distribution of galaxies located within the distance which is unaffected by the GZK cutoff ($\sim 50$ Mpc). We find that the reconnection efficiency factor needs to be $\xi \gtrsim 0.1$ in order to reproduce the observed flux of UHECRs.Comment: Latex file, 16 pages, 2 figures, replaced with revised version accepted for publication in the ApJ letter

Noether's Symmetry Theorem for Variational and Optimal Control Problems with Time Delay

We extend the DuBois-Reymond necessary optimality condition and Noether's symmetry theorem to the time delay variational setting. Both Lagrangian and Hamiltonian versions of Noether's theorem are proved, covering problems of the calculus of variations and optimal control with delays.Comment: This is a preprint of a paper whose final and definite form will appear in the international journal Numerical Algebra, Control and Optimization (NACO). Paper accepted for publication 15-March-201

(De)Bonding with embryos: The emotional choreographies of Portuguese IVF patients

In this article we develop the new concept of emotional choreography to describe how patients bond, debond and/or rebond with their embryos created in vitro using assisted reproductive technologies (ART). Using this concept, we explore how the patients' management of their own emotions intertwines with political, scientific, and religious factors. Our analysis relies on and further advances Thompson's concepts of ethical and ontological “choreography”. It is through these forms of choreography that complex contemporary biomedical issues with high political, ethical, and scientific stakes are negotiated, and through which different actors, entities, practices, roles, and norms undergo mutual constitution, reinforcement and (re)definition. Our article draws on the analysis of 69 in-depth interviews and the results of an online survey with 85 respondents.info:eu-repo/semantics/publishedVersio

The mixed capacitated arc routing problem with non-overlapping routes

Real world applications for vehicle collection or delivery along streets usually lead to arc routing problems, with additional and complicating constraints. In this paper we focus on arc routing with an additional constraint to identify vehicle service routes with a limited number of shared nodes, i.e. vehicle service routes with a limited number of intersections. This constraint leads to solutions that are better shaped for real application purposes. We propose a new problem, the bounded overlapping MCARP (BCARP), which is defined as the mixed capacitated arc routing problem (MCARP) with an additional constraint imposing an upper bound on the number of nodes that are common to different routes. The best feasible upper bound is obtained from a modified MCARP in which the minimization criteria is given by the overlapping of the routes. We show how to compute this bound by solving a simpler problem. To obtain feasible solutions for the bigger instances of the KARP heuristics are also proposed. Computational results taken from two well known instance sets show that, with only a small increase in total time traveled, the model BCARP produces solutions that are more attractive to implement in practice than those produced by the MCARP modelinfo:eu-repo/semantics/submittedVersio

Super-efficiency and stability intervals in additive DEA

This is a PDF file of an unedited manuscript that has been accepted for publication in Journal of the Operational Research Society. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. The final version will be available at: http://dx.doi.org/10.1057/jors.2012.1

Principais clostridioses dos ovinos e caprinos: sinais clínicos e medidas preventivas.

bitstream/item/31671/1/Comunicado-Tecnico-144.pd

Avaliação do crescimento de espécies florestais por grupo ecológico em áreas exploradas na Flona do Tapajós.

III ENAAg

Avaliação do potencial farmacológico de metabolitos secundários de Cystoseira abies-marina

Dissertação de Mestrado em Ciências Biomédicas.A pesquisa de Produtos Naturais com propriedades farmacológicas tem vindo a crescer, destacando-se a descoberta de moléculas vindas de organismos marinhos, que devido à sua considerável biodiversidade se reflecte em metabolitos secundários com estruturas únicas e com várias funcionalidades. Este trabalho surge no seguimento de uma investigação feita com algas do mar dos Açores, cujas actividades biológicas se mostraram promissoras. Nesta tese intitulada “Avaliação do potencial farmacológico de metabolitos secundários de Cystoseira abies-marina”, faz-se um estudo fitoquímico e determinam-se algumas actividades biológicas de compostos isolados. No capítulo I apresentam-se os objectivos e faz-se uma descrição das características da alga em estudo, bem como um pequeno resumo da literatura referente aos compostos isolados de algas do género Cystoseira. A elucidação estrutural dos cinco compostos isolados (o ácido benzóico, um composto natural já conhecido, o cystoazores A, o cystoazores B, o cystoazorona A e o cystoazorona B, meroditerpenos isolados pela primeira vez), e as actividades destes compostos (antitumoral, antioxidante, anticolinesterásica e anti-inflamatória) são apresentadas e discutidas no Capitulo II. Os resultados mostram que os compostos cystoazores A, cystoazores B e cystoazorona A apresentam actividade antitumoral, mas com baixa selectividade entre a linhagem tumoral HeLa e a linhagem não tumoral Vero usada como referência. Na actividade antioxidante, nenhum dos compostos testados apresentaram IC50 <500 μg/mL.. Os compostos mais activos como anticolinesterásicos foram o cystoazores A e B, apesar de não terem atingido 50% de inibição da enzima à concentração máxima testada (125 μg/mL). Quanto à actividade anti-inflamatória in vitro, o ácido benzóico e a cystoazorona B foram os únicos que inibiram ambas as formas da cicloxigenase (COX1 e COX2), comportando-se no entanto como pro-inflamatórios em relação à lipoxigenase 15-LOX. No capítulo III são apresentados os detalhes dos procedimentos experimentais utilizados neste trabalho de investigação.ABSTRACT: The search for Natural Products with pharmacological properties has been increasing, particularly the discovery of molecules isolated from marine organism, whose considerable biodiversity is reflected in secondary metabolites with unique structures and functions. This work is carried out in the sequence of a preliminary investigation on the marine algae of the Azores, which detected promising biological activities. In this thesis, entitled “Evaluation of the pharmacological potential of secondary metabolites from Cystoseira abies-marina”, a phytochemical study is carried out and several biological activities of isolated compounds are determined. Chapter I presents the objectives and characterizes the under study, and also a summary of the literature concerning compounds isolated from the Cystoseira genus. The structural elucidation of five isolated compounds (benzoic acid, a known natural compound, cystoazores A, cystoazores B, cystoazorone A and cystoazorone B, meroditerpenes isolated for the first time) and the activity of these compounds (antitumour, antioxidant, anticholinesterasic and anti-inflammatory) are presented and discussed in Chapter II. The results show that cystoazores A, cystoazores B and cystoazorone A are actively cytotoxic, but with low selectivity between HeLa tumour cell line and Vero non tumour cell line, used as reference. Concerning antioxidant activity, none of the compounds tested presented IC50<500 μg/mL. Cystoazores A and B had the strongest anticholinesterasic activity, although 50% inhibition of enzyme activity was not attained at the highest concentration tested (125 μg/mL). Regarding in vitro anti-inflammatory activity, benzoic acid and cystoazorone B were the only two that inhibited both isoforms of cyclooxygenase (COX1 and COX2), although they behaved as pro-inflammatory towards lipoxygenase 15-LOX. Chapter III presents details of experimental procedures used in this research