6,046 research outputs found

    Axial gravity, massless fermions and trace anomalies

    Get PDF
    This article deals with two main topics. One is odd parity trace anomalies in Weyl fermion theories in a 4d curved background, the second is the introduction of axial gravity. The motivation for reconsidering the former is to clarify the theoretical background underlying the approach and complete the calculation of the anomaly. The reference is in particular to the difference between Weyl and massless Majorana fermions and to the possible contributions from tadpole and seagull terms in the Feynman diagram approach. A first, basic, result of this paper is that a more thorough treatment, taking account of such additional terms { and using dimensional regularization}, confirms the earlier result. The introduction of an axial symmetric tensor besides the usual gravitational metric is instrumental to a different derivation of the same result using Dirac fermions, which are coupled not only to the usual metric but also to the additional axial tensor. The action of Majorana and Weyl fermions can be obtained in two different limits of such a general configuration. The results obtained in this way confirm the previously obtained ones.Comment: 55 pages, comments added in section 2 and 5. Sections 6.4, 6.6, 7, 7.1, 7.2 and Appendices 5.3, 5.5 partially modifie

    Happy 2 Smell (H2S)

    Get PDF
    A problem was initially identified: the emission of polluting gases into the atmosphere, namely hydrogen sulphide, H2S, by the tanneries close to our school district. After carrying out theoretical investigations in Biology and Chemistry, the students developed an idea for a project, which consisted of creating a biological filter, with a porous matrix that could be easily traversed by the H2S gas, using, for this purpose, the dry fruit of the plant Luffa aegyptiaca. This material possesses a high porosity and good physical and chemical resistance, serving as a support matrix for sulphur bacteria and, initially, also their culture medium. In collaboration with Alcanena's Wastwater Treatment Plant, sludge from different treatment stages containing sulphurous bacteria were collected. These bacteria manage to transform H2S into sulphur and water. Finally, in collaboration with CTIC (Technological Center for the Leather Industry), iodometric titrations were carried out, proving the effectiveness of the produced filter

    Modulation of Autophagy in Adrenal Tumors

    Get PDF
    Adrenal masses are one of the most common tumors in humans. The majority are benign and non-functioning and therefore do not require immediate treatment. In contrast, the rare adrenal malignant tumors are often highly aggressive and with poor prognosis. Besides usually being detected in advanced stages, often already with metastases, one of the reasons of the unfavorable outcome of the patients with adrenal cancer is the absence of effective treatments. Autophagy is one of the intracellular pathways targeted by several classes of chemotherapeutics. Mitotane, the most commonly used drug for the treatment of adrenocortical carcinoma, was recently shown to also modulate autophagy. Autophagy is a continuous programmed cellular process which culminates with the degradation of cellular organelles and proteins. However, being a dynamic mechanism, understanding the autophagic flux can be highly complex. The role of autophagy in cancer has been described paradoxically: initially described as a tumor pro-survival mechanism, different studies have been showing that it may result in other outcomes, namely in tumor cell death. In adrenal tumors, this dual role of autophagy has also been addressed in recent years. Studies reported both induction and inhibition of autophagy as a treatment strategy of adrenal malignancies. Importantly, most of these studies were performed using cell lines. Consequently clinical studies are still required. In this review, we describe what is known about the role of autophagy modulation in treatment of adrenal tumors. We will also highlight the aspects that need further evaluation to understand the paradoxical role of autophagy in adrenal tumors

    Giardia sp. and Cryptosporidium sp. in Iberian Wolf

    Get PDF
    ΔΕΝ ΔΙΑ΀ΙΘΕ΀ΑΙ ΠΕΡΙΛΗιΗA subsample consisting of fifty fecal samples from wild Iberian Wolf (Canis lupus signatus), from the northwest of Spain were collected in the field. The samples were analyzed for cysts of Giardia sp. and oocysts of Cryptosporidium sp. using a direct immunofluorescence antibody test (IFA). Giardia sp. and Cryptosporidium sp. were found in 20.0 % of the samples examined. Simple infections were more frequent (90.0 %) with seven (14.0 %) positive for Giardia sp. and two (4.0 %) positive for Cryptosporidium sp. To the authors’ knowledge, this is the first report of occurrence of Cryptosporidium sp. in Iberian Wolf

    How do families represent the functions of deliberate self-harm? A comparison between the social representations from Adolescents and Their Parents

    Get PDF
    Research has recognized the importance of understanding the social representations about the functions of deliberate self-harm, particularly in the context of clinical intervention. In addition, parents can play a relevant role in the rehabilitation of adolescents with these behaviors. However, there are few studies that focused on the description and comparison of the social representations about these functions, particularly in families. This article aimed to analyze the social representations about the functions of deliberate self-harm from adolescents and their parents. We developed two sets of analyses: first we compared the social representations from adolescents without a history of deliberate self-harm and their parents, and secondly we compared the social representations about the functions of deliberate self-harm from adolescents with a history of these behaviors and their parents' social representations. Results revealed significant differences between both groups of families, implying that the groups of participants represent the functions of deliberate self-harm differently. Overall, parents emphasized interpersonal functions and devalued intrapersonal functions. These differences were heightened in the families of adolescents with deliberate self-harm. The present article provides important insights regarding the social representations about the functions of deliberate self-harm and the differences between parents' social representations and their children experiences and social representations.info:eu-repo/semantics/publishedVersio

    Chitosan and polyethylene glycol based membranes with antibacterial properties for tissue regeneration

    Get PDF
    The prevention of microbial infections associated with implantable medical devices and superficial wounds represents one of the main research strategies in the field of biomaterials. The present study reports on the development of composite membranes of Chitosan (CS)-Polyethylene glycol (PEG) matrix, incorporating particles of biphasic calcium phosphate (BCP), zinc oxide (ZnO) and copper oxide (CuO). The properties that are relevant for intended applications in tissue regeneration and antibacterial coatings of implants were assessed. It was found that the addition of 1% (w/w - relative to the mass of CS) of each metal oxide promoted satisfactory bacteriostatic activity and exhibited no cytotoxic effects towards the Vero cell line. The formation of bonds between the CS/PEG matrix and ionic species from the powders enhanced the cross-linking degree and mechanical properties of composite membranes in comparison to the non-doped membrane with the same polymer matrix (CS/PEG = 70/30%). A gradual degradation of the composite membranes over the immersion time in simulated body fluid (SBF) was accompanied by a continuous surface deposition of uniform apatite layer.publishe

    Auditoria Ă  prĂĄtica profilĂĄtica e incidĂȘncia de nĂĄuseas e vĂłmitos pĂłs-operatĂłrios (NVPO)

    Get PDF
    Introdução: As NVPO sĂŁo uma das principais queixas dos doentes do pĂłs-operatĂłrio. Este trabalho teve como objetivo registar a prĂĄtica farmacolĂłgica para profilaxia de NVPO em cirurgia programada e avaliar a sua eficĂĄcia. Metodologia: IncluĂ­dos todos os doentes submetidos a cirurgia programada das especialidades de Cirurgia Geral, Urologia e Cirurgia Vascular entre 3 e 21 de Dezembro de 2012. ExcluĂ­dos se alta<24horas(h), pĂłs-operatĂłrio no Serviço Cuidados Intensivos/ IntermĂ©dios ou impossĂ­vel acesso aos registos. Tendo como modelos o Score Apfel Simplificado e as recomendaçÔes para cirurgia de ambulatĂłrio(1) (Tabela 1), a profilaxia instituĂ­da foi dividida em adequada, a mais ou a menos; avaliação da ocorrĂȘncia de NVPO na Unidade Cuidados PĂłs-AnestĂ©sicos e Ă s 24h (registos anestĂ©sicos e entrevista). Resultados apresentados em percentagem. Aplicação teste qui quadrado com p<0,05 para significĂąncia. Resultados: Avaliados 255 doentes (excluĂ­dos 68, incluĂ­dos 187). Com 0-1 fator risco (FR) 34%, 2 FR 45%, 3-4 FR 21%. A profilaxia foi adequada em 53% dos doentes, a mais em 16% e a menos em 31%. IncidĂȘncia total de NVPO - 22% (24% no grupo de doentes que fez profilaxia adequada e 20% no grupo de profilaxia inadequada (p=0.35012)). Neste Ășltimo grupo 13% realizaram profilaxia a mais e 24% a menos. Resultados da incidĂȘncia de NVPO por fator de risco na tabela 2. A incidĂȘncia de NVPO por FR nos doentes com profilaxia adequada foi menor ou igual em todos os grupos em relação ao previsto no Score Apfel simplicado(1,2). No grupo que fez profilaxia inadequada, esta foi a menos principalmente no grupo de 2 FR, com 71% de NVPO; e foi a mais essencialmente no grupo com 1 FR (4 doentes, todos com NVPO). IncidĂȘncia menor com anestesia locoregional (ALR) vs anestesia geral (AG) (13% vs 27%) (p<0.001). DiscussĂŁo e ConclusĂ”es: A profilaxia foi adequada, segundo as recomendaçÔes para cirurgia de ambulatĂłrio, em cerca de metade dos doentes. Apesar da profilaxia adequada, nos grupos de FR 1 e 2 nĂŁo houve redução da incidĂȘncia de NVPO comparando com a prevista pelo score de Apfel, alertando para a importĂąncia de outros fatores de risco nĂŁo previstos neste score e que estas recomendaçÔes poderĂŁo ser insuficientes para a profilaxia de NVPO em cirurgia em regime de internamento. A incidĂȘncia de NVPO foi menor com ALR vs AG, corroborando a ALR como melhor opção em doentes de risco de NVPO (1,2). Estes resultados salientam a importĂąncia da adoção de estratĂ©gias para redução do risco basal

    Development of a fast screening method for the direct determination of chlorinated persistent organic pollutants in fish oil by high-resolution continuum source graphite furnace molecular absorption spectrometry

    Get PDF
    The authors are grateful to the Conselho Nacional de Desenvolvimento Científico and Tecnológico (CNPq); the present research was mostly financed through Project no. CNPq 406877/2013-0. The authors are also grateful to the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for financial support and scholarships, and to Analytik Jena for financial support and donation of the contrAA 600 high-resolution continuum source atomic absorption spectrometer.Peer reviewedPostprin

    Esports Sponsorships: The Double-Edged Sword Effect of Having a Very Vocal Audience

    Get PDF
    Esports fans have been known for being heavy consumers of compet itive gaming content and for being digital natives who love to comment about esports on numerous social platforms. This has attracted various sponsors inter ested in capitalizing in this social buzz. However, there have been signs that this high vocality can in fact heavily damage several sponsors. Hence, this research aimed to determine if esports fans’ high vocality is a benefit and/or a risk to these sponsors. To achieve this, we adopted a qualitative exploratory design to interview, via digital platforms, 10 esports sponsorship experts. In total, we in terviewed two endemic and three non-endemic esports sponsors and five mar keting agencies with experience in esports sponsorships. They were sampled via a nonprobability purposive heterogeneous method and were reached via the companies’ website contact sections. Data were analyzed with the assistance of NVivo 10. The overall results showed that all experts agreed that this high vo cality can both benefit and damage esports sponsors. The uniformity in the an swers showed that this element is not a greater benefit or risk to a particular type of esports sponsor. Ergo we considered that the high vocality of esports fans is a double-edged sword. This study is necessary because, despite esports’ massive growth, this field has received scant scientific attention, with the spe cific areas of esports marketing and esports sponsorships being even more se verely overlooked. Besides, from a business standpoint, the findings are highly significant for every sponsor looking to better comprehend esports and its fan baseinfo:eu-repo/semantics/publishedVersio
    • 

    corecore