6,580 research outputs found

    Spontaneous symmetry breaking in amnestically induced persistence

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    We investigate a recently proposed non-Markovian random walk model characterized by loss of memories of the recent past and amnestically induced persistence. We report numerical and analytical results showing the complete phase diagram, consisting of 4 phases, for this system: (i) classical nonpersistence, (ii) classical persistence (iii) log-periodic nonpersistence and (iv) log-periodic persistence driven by negative feedback. The first two phases possess continuous scale invariance symmetry, however log-periodicity breaks this symmetry. Instead, log-periodic motion satisfies discrete scale invariance symmetry, with complex rather than real fractal dimensions. We find for log-periodic persistence evidence not only of statistical but also of geometric self-similarity.Comment: 4 pages, 2 color fig

    Polyomavirus Nephropathy: Ten-Year Experience

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    BACKGROUND: Polyomavirus nephropathy (BKVN) is an important cause of chronic allograft dysfunction (CAD). Recipient determinants (male sex, white race, and older age), deceased donation, high-dose immunosuppression, diabetes, delayed graft function (DGF), cytomegalovirus infection, and acute rejection (AR) are risk factors. Reducing immunosuppression is the best strategy in BKVN. The objective of our study was to evaluate CAD progression after therapeutic strategies in BKVN and risk factors for graft loss (GL). METHODS: Retrospective analysis of 23 biopsies, from patients with CAD and histological evidence of BKVN, conducted over a period of 10 years. Glomerular filtration rate was <30 mL/min in 16 patients at the time of the BKVN diagnosis. RESULTS: BKVN was histologically diagnosed in 23 recipients (19 men, 4 women). All patients were white, with age of 51.2 ± 12.1 years (6 patients, age >60 years), and 22 had a deceased donor. Diabetes affected 4 patients, DGF occurred in 3, cytomegalovirus infection in 2, and AR in 15. All patients were medicated with calcineurin inhibitors (CNI) (95.7% tacrolimus) and corticoids, and 16 also received an antimetabolite. One year after antimetabolite reduction/discontinuation and/or CNI reduction/switching and/or antiviral agents, graft function was decreased in 11 patients, increased/stabilized in 10, and unknown in 2. GL occurred in 9 patients. Older age (hazard ratio, 1.76; 95% confidence interval, 0.94-3.28) and DGF (hazard ratio, 2.60; 95% confidence interval, 0.54-12.64) were the main risk factors for GL. The lower GFR at the time of the BKVN diagnosis was associated with an increased risk of initiation of dialysis. CONCLUSIONS: GL occurred in 39.1% of patients with BKVN and DGF; older age and lower GFR at the time of diagnosis were important risk factors. Early diagnosis of BKVN is essential to prevent GL.info:eu-repo/semantics/publishedVersio

    Carbon Neutral Brazilian Beef: testing its guidelines through a case study.

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    The Carbon Neutral Brazilian Beef (CNBB) is a new concept for sustainable beef production in the tropics, developed by Embrapa and first reported by Alves et al. (2015). The CNBB concept is based in silvopastoral or agrosilvopastoral systems and requires greenhouse gases emissions to be neutralized, at first, by timber production. Aim of this work is to report the first case study of CNBB application for finishing steers and to present animal performance, beef quality, pasture characteristics, microclimate parameters and carbon balance estimates

    Expressed sequence-tag analysis of ovaries of Brachiaria brizantha reveals genes associated with the early steps of embryo sac differentiation of apomictic plants.

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    Abstract - In apomixis, asexual mode of plant reproduction through seeds, an unreduced megagametophyte is formed due to circumvented or altered meiosis. The embryo develops autonomously from the unreduced egg cell, independently of fertilization. Brachiaria is a genus of tropical forage grasses that reproduces sexually or by apomixis. A limited number of studies have reported the sequencing of apomixis-related genes and a few Brachiaria sequences have been deposited at genebank databases. This work shows sequencing and expression analyses of expressed sequence-tags (ESTs) of Brachiaria genus and points to transcripts from ovaries with preferential expression at megasporogenesis in apomictic plants. From the 11 differentially expressed sequences from immature ovaries of sexual and apomictic Brachiaria brizantha obtained from macroarray analysis, 9 were preferentially detected in ovaries of apomicts, as con?rmed by RT-qPCR. A putative involvement in early steps of Panicum-type embryo sac differentiation of four sequences from B. brizantha ovaries: BbrizHelic, BbrizRan, BbrizSec13 and BbrizSti1 is suggested. Two of these, BbrizSti1 and BbrizHelic, with similarity to a gene coding to stress induced protein and a helicase, respectively, are preferentially expressed in the early stages of apomictic ovaries development, especially in the nucellus, in a stage previous to the differentiation of aposporous initials, as veri?ed by in situ hybridization

    In Vitro Activity of Ceftolozane-Tazobactam Against Enterobacterales and Pseudomonas Aeruginosa Causing Urinary, Intra-Abdominal and Lower Respiratory Tract Infections in Intensive Care Units in Portugal: the STEP Multicenter Study

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    The STEP surveillance study was designed to increase knowledge about distribution of multidrug-resistant (MDR) Enterobacterales and Pseudomonas aeruginosa in Portugal, focusing on the intensive care unit (ICU). Antimicrobial susceptibility of common agents was also evaluated and compared with that of one of the latest therapeutic introductions, ceftolozane-tazobactam (C/T). Clinical isolates of Enterobacterales (n=426) and P. aeruginosa (n=396) from patients admitted in Portuguese ICUs were included. Activity of C/T and comparators was investigated using standard broth microdilution. Isolates were recovered from urinary tract (UTI, 36.9%), intra-abdominal (IAI, 24.2%) and lower respiratory tract (LRTI, 38.9%) infections. In P. aeruginosa, overall distribution of MDR/extremely-drug resistant (XDR)/pan-drug resistant (PDR) isolates accounted for 21.2%, 23.2% and 0.8%, respectively. C/T was the most potent agent tested against P. aeruginosa and MDR/XDR/PDR phenotypes. In Escherichia coli, extended-spectrum beta-lactamases (ESBL) and carbapenemase (CP) phenotypes accounted for 16.6% and 1.7%, respectively, whereas in Klebsiella spp., ESBL and CP-phenotypes represented 28.5% and 17.9%, respectively. Overall, susceptibility of C/T against Enterobacterales was 86.9%. C/T was the least affected agent in E. coli (99.4% susceptibility), whereas its activity was moderate in Klebsiella spp. (71.5%) and Enterobacter spp. (70.4%), due in part to a high rate of ESBL and CP-phenotypes. In Enterobacterales, blaKPC was the most prevalent CP gene (63.0%), followed by blaOXA-48 (33.3%) and blaVIM (3.7%). These microbiological results reinforce C/T as a therapeutic option in ICU patients with UTI, IAI or LRTI due to P. aeruginosa or Enterobacterales isolates, but not for CP producers.info:eu-repo/semantics/publishedVersio

    Evolução das principais doenças em lavouras de cafeeiros no município de Lavras, MG, nos anos agrícolas 2011-2012 e 2012-2013 - Projeto SIMAFF.

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    No Brasil, os órgãos de pesquisa envolvidos com a cultura cafeeira sempre têm procurado investimentos para os avanços tecnológicos para a produção, qualidade e competitividade no mercado nacional e internacional. Nesse sentido, a EMBRAPA/Café vem coordenando um projeto cuja finalidade consiste em realizar o monitoramento agrometeorológico, fenológico e fitossanitário do café arábica nos estados de Minas Gerais, São Paulo e Paraná, sendo que, essas informações serão disponibilizadas via internet no sistema denominado SIMAFF-Café. O SIMAFF-Café terá como principal função subsidiar os cafeicultores e/ou órgãos competentes quanto ao acompanhamento produtivo do cafeeiro, permitindo assim tomar decisões nesse agronegócio. Portanto, várias áreas de lavouras cafeeiras amostrais dos Estados envolvidos estão sendo constantemente monitoradas desde o início do projeto (novembro/2011). Especificamente para Lavras, MG, região Sul do Estado, quanto às doenças do cafeeiro, acompanhou-se, mensalmente, nos anos agrícolas 2011-2012 e 2012-2013, as suas respectivas evoluções para cada ano agrícola na fazenda denominada ?Macaco?. O acompanhamento das possíveis doenças auxilia o produtor na tomada de decisões quanto ao controle e até mesmo no manejo nutricional da lavoura. A escolha dos talhões atendeu à metodologia da Fundação PROCAFÉ sediada em Varginha, MG e adotada como padrão pelo SIMAFF. Foram selecionadas duas variedades Catuaí (CT) e Icatu (IC). No ano 2011-2012 para a ocorrência da ferrugem, em ambas as variedades, o auge da infestação foi entre abril e junho, sendo o CT mais intensamente infestado. Já no ano agrícola 2012-2013 os índices de ferrugem apresentaram valores atípicos para os meses compreendidos entre outubro e maio. Para ambos os anos agrícolas, a infestação por Cercóspora foi mais intensa para a variedade Catuaí, destacando os meses de novembro e dezembro. Quanto ao ataque da Phoma, no ano de 2011-2012, o Icatú atingiu índices de infestação ligeiramente superiores ao Catuaí, sendo que os maiores índices ocorreram entre maio e junho, atingindo até 60 % no IC, espaçamento largo (L) e carga alta (A). Contudo no ano 2012-2013, esse comportamento tendeu a se inverter, sendo que os maiores valores de infestação ocorreram em outubro e entre fevereiro e março

    Zootherapeutics utilized by residents of the community Poço Dantas, Crato-CE, Brazil

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    <p>Abstract</p> <p>Background</p> <p>Animals have been used as a source of medicine in Brazil since ancient times, and have played a significant role in healing practices. Specifically in Northeast Brazil, zootherapy is a very common practice, and together with medicinal plants, it plays an important role as a therapeutic alternative. In the state of Ceara, no works have been carried out on rural communities with regard to use of zootherapeutics, even though the practice of zootherapy is common in this region. Therefore, the aim of this study was to analyze the use of medicinal animals in a rural community (Poco Dantas) in the municipality of Crato, Ceara, Brazil.</p> <p>Methods</p> <p>The field survey was carried out from October 2008 to January 2009 by conducting interviews using structured questionnaires with 72 people (33 men and 39 women), who provided information on animal species used as remedies, body parts used to prepare the remedies, and ailments for which the remedies were prescribed. We calculated the informant consensus factor (ICF) to determine the consensus over which species are effective for particular ailments, as well as the species use value (UV) to determine the extent of utilization of each species.</p> <p>Results</p> <p>A total of 29 species, distributed in 17 families were categorized as having some medicinal property. The taxa most represented were: mammals (9), insects (7), reptiles and birds (4). <it>Progne chalybea</it>, a species not previously recorded as being of medicinal use, was cited in the present work, where it is utilized in the treatment of alcoholism. The animals are used in the treatment of 34 diseases or symptoms, where sore throat, inflammations and cough are the ailments with the greatest number of citations.</p> <p>Conclusion</p> <p>The data show that zootherapy represents an important therapeutic alternative for the inhabitants of the community. New studies on medicinal fauna should be conducted with the aim of determining the exploitation level of the species utilized, promoting sustainable development of medicinal species that are eventually threatened, and preserving and disseminating the knowledge developed by traditional individuals of the community.</p
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