712 research outputs found
Descritores morfológicos quantitativos de passiflora setacea em cultivos orgânicos e convencionais.
O gĂŞnero Passiflora tem como principais caracterĂsticas serem plantas trepadeiras herbáceas ou lenhosas de ramos cilĂndricos ou quadrangulares, angulosas, suberificadas, glabras ou pilosas (TEIXEIRA, 1994). O Brasil Ă© um dos centros da diversidade de espĂ©cies do gĂŞnero, com estimativas de que existam mais de 200 espĂ©cies muitas distribuĂdas nas áreas de Cerrado (Souza e Meletti, 1997). A Passiflora setacea Ă© uma dessas espĂ©cies nativas encontradas nos biomas Cerrado e Caatinga (OLIVEIRA; RUGIERO, 2005). De acordo com a descrição botânica da espĂ©cie, a P. setacea apresenta caule cilĂndrico tomentoso com tricomas suaves e macios. EstĂpulas setáceas, de 5 mm, decĂduas. PecĂolos de 3 cm, prĂłximos Ă base foliar, com um par de glândulas sĂ©sseis, medindo cerca de 1 mm de largura. Folhas de 5-8 Ă— 6-10 cm, trilobadas (lĂłbulos oblongos ou oblongo-lanceolados), serreadas nos bordos, cordadas na base, trinervadas, membranáceas a subcoriáceas, normalmente pilosas em ambas as superfĂcies; tricomas macios ao tato; raramente glabras em uma das superfĂcies. PedĂşnculos de 8-10 cm, robustos, articulados perto do ápice, tomentosos. Brácteas em nĂşmero de trĂŞs, verticiladas, situadas cerca de 1 cm da base floral, oblongo-lanceoladas, acuminadas no ápice, estreitando-se na base; bordo serreado ou da metade para o ápice. Flores com cerca de 10 cm de diâmetro. Tubo do cálice cilĂndrico campanulado, de 1,5 cm. SĂ©palas oblongas, margem verde e centro branco, carenadas (dorsalmente existe uma arista setácea de 1 a 1,5 cm de comprimento), na face abaxial numerosas glândulas sĂ©sseis. PĂ©talas linear-oblongas, alvas. Corona de filamentos em uma Ăşnica sĂ©rie, de 1 cm de comprimento; filamentos subulados, bandeados de branco e azul. OpĂ©rculo membranoso, tubular, ereto, fimbriado no terço superior. Limen cupuliforme, envolvendo frouxamente a base do androginĂłforo. Ovário elipsoidal, glabro. Fruto ovĂłide, aveludado. Sementes obovadas, foveoladas (CERVI, 1997). Os descritores morfolĂłgicos botânicos tĂŞm como objetivo a coleta de dados referentes a caracterĂsticas como dimensĂŁo, massa e cor de frutos, flores, folhas e sementes. Conhecimento esse que Ă© importante para a caracterização de espĂ©cies e variedades e sĂŁo determinantes para orientar trabalhos de melhoramento genĂ©tico, alem de gerar subsĂdios para o sistema de produção e servirem de referĂŞncia para o registro e proteção de cultivares no MinistĂ©rio da Agricultura, Pecuária e Abastecimento (MAPA). Essas caracterĂsticas observadas para a obtenção dos descritores botânicos, podem se alterar de acordo com o ambiente em que a planta esta localiza, já que plantas podem tem respostas diferentes em seu desenvolvimento frente Ă disponibilidade de nutrientes no solo, luz, água, suscetibilidade a pragas e outras questões ambientais (RAVEN, 1996). Dessa forma uma mesma espĂ©cie, quando cultivada em tratamentos orgânicos e convencionais, pode apresentar aspectos morfolĂłgicos diferentes entre os seus indivĂduos, e como nos Ăşltimos anos houve um constante crescimento da demanda por produtos orgânicos e ecologicamente corretos (ORMOND et al, 2002), Ă© indispensável que se tenha noção de como certas espĂ©cies se comportam frente a um tratamento orgânico, e se existe viabilidade comercial em sua produção. Portanto o objetivo do presente trabalho foi verificar se indivĂduos da espĂ©cie Passiflroa setacea apresentam diferenças morfolĂłgicas quando submetidos a cultivo convencional ou orgânico
Surgical Site Infections in Italy, 2009-2015: Incidence, Trends, and Impact of Surveillance Duration on Infection Risk
The Italian policy of mandating SARS-CoV-2 vaccination for healthcare workers: Analysis of the policy processes and preliminary outcomes
timed flat infusion tfi 5 fluorouracil with irinotecan and oxaliplatin in pancreatic adenocarcinomas a single institution experience with fir fox regimen
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Surgical antimicrobial prophylaxis prescribing practices and impact on infection risk: Results from a multicenter surveillance study in Italy (2012-2017)
Covalent functionalization enables good dispersion and anisotropic orientation of multi-walled carbon nanotubes in a poly(l-lactic acid) electrospun nanofibrous matrix boosting neuronal differentiation
A biocompatible porous scaffold obtained via electrospinning a nanocomposite solution of poly(l-lactic acid) and 4-methoxyphenyl functionalized multi-walled carbon nanotubes is presented here for the first time for the enhancement of neurite outgrowth. Optimization of blend preparation and deposition parameters paves the way to the obtainment of defect-free random networks of nanofibers with homogeneous diameters in the hundreds of nanometers length scale. The tailored covalent functionalization of nanotube surfaces allows a homogeneous dispersion of the nanofillers within the polymer matrix, diminishing their natural tendency to aggregate and form bundles. This results in a remarkable effect on the crystallization temperature, as evidenced through differential scanning calorimetry. Furthermore, transmission electron microscopy shows carbon nanotubes anisotropically aligned along the fiber axes, a feature believed to enhance neurite adhesion and growth. Indeed, microscopy images show neurites extension along the direction of nanofibers, highlighting the extreme relevance of scaffold morphology in engineering complex tissue environments. Furthermore, a remarkable effect on increasing the neurite outgrowth results when using the fibrous scaffold containing dispersed carbon nanotubes in comparison with an analogous one made of only polymer, providing further evidence of the key role played by carbon nanostructures in inducing neuronal differentiation
Revisiting the hyperdominance of Neotropical tree species under a taxonomic, functional and evolutionary perspective
Recent studies have leveraged large datasets from plot-inventory networks to report a phenomenon of hyperdominance in Amazonian tree communities, concluding that few species are common and many are rare. However, taxonomic hypotheses may not be consistent across these large plot networks, potentially masking cryptic diversity and threatened rare taxa. In the current study, we have reviewed one of the most abundant putatively hyperdominant taxa, Protium heptaphyllum (Aubl.) Marchand (Burseraceae), long considered to be a taxonomically difficult species complex. Using morphological, genomic, and functional data, we present evidence that P. heptaphyllum sensu lato may represent eight separately evolving lineages, each warranting species status. Most of these lineages are geographically restricted, and few if any of them could be considered hyperdominant on their own. In addition, functional trait data are consistent with the hypothesis that trees from each lineage are adapted to distinct soil and climate conditions. Moreover, some of the newly discovered species are rare, with habitats currently experiencing rapid deforestation. We highlight an urgent need to improve sampling and methods for species discovery in order to avoid oversimplified assumptions regarding diversity and rarity in the tropics and the implications for ecosystem functioning and conservation
Synthetic wastewaters treatment by electrocoagulation to remove silver nanoparticles produced by different routes
International audienceNanoscience is a field that has stood out in recent years. The accurate long-term health and environmental risks associated with these emerging materials are unknown. Therefore, this work investigated how to eliminate silver nanoparticles (AgNPs) from synthetic effluents by electrocoagulation (EC) due to the widespread use of this type of nanoparticle (NP) in industry and its potential inhibition power over microorganisms responsible for biological treatment in effluent treatment plants. Synthesized AgNPs were studied via four different routes by chemical reduction in aqueous solutions to simulate the chemical variations of a hypothetical industrial effluent, and efficiency conditions of the EC treatment were determined. All routes used silver nitrate as the source of silver ions, and two synthesis routes were studied with sodium citrate as a stabilizer. In route I, sodium citrate functioned simultaneously as the reducing agent and stabilizing agent, whereas route II used sodium borohydride as a reducing agent. Route III used d-glucose as the reducing agent and sodium pyrophosphate as the stabilizer; route IV used sodium pyrophosphate as the stabilizing agent and sodium borohydride as the reducing agent. The efficiency of the EC process of the different synthesized solutions was studied. For route I, after 85Â min of treatment, a significant decrease in the plasmon resonance peak of the sample was observed, which reflects the efficiency in the mass reduction of AgNPs in the solution by 98.6%. In route II, after 12Â min of EC, the absorbance results reached the detection limit of the measurement instrument, which indicates a minimum reduction of 99.9% of AgNPs in the solution. During the 4Â min of treatment in route III, the absorbance intensities again reached the detection limit, which indicates a minimum reduction of 99.8%. In route IV, after 10Â min of treatment, a minimum AgNP reduction of 99.9% was observed. Based on these results, it was possible to verify that the solutions containing citrate considerably increased the necessary times required to eliminate AgNPs from the synthesized effluent, whereas solutions free of this reagent showed better results on floc formation and, therefore, are best for the treatment. The elimination of AgNPs from effluents by EC proved effective for the studied routes
Transcribed ultraconserved noncoding RNAs (T-UCR) are involved in Barrett's esophagus carcinogenesis.
Barretts esophagus (BE) involves a metaplastic replacement of native esophageal squamous epithelium (Sq) by columnar-intestinalized mucosa, and it is the main risk factor for Barrett-related adenocarcinoma (BAc). Ultra-conserved regions (UCRs) are a class non-coding sequences that are conserved in humans, mice and rats. More than 90% of UCRs are transcribed (T-UCRs) in normal tissues, and are altered at transcriptional level in tumorigenesis. To identify the T-UCR profiles that are dysregulated in Barretts mucosa transformation, microarray analysis was performed on a discovery set of 51 macro-dissected samples obtained from 14 long-segment BE patients. Results were validated in an independent series of esophageal biopsy/surgery specimens and in two murine models of Barretts esophagus (i.e. esophagogastric-duodenal anastomosis). Progression from normal to BE to adenocarcinoma was each associated with specific and mutually exclusive T-UCR signatures that included up-regulation of uc.58-, uc.202-, uc.207-, and uc.223- and down-regulation of uc.214+. A 9 T-UCR signature characterized BE versus Sq (with the down-regulation of uc.161-, uc.165-, and uc.327-, and the up-regulation of uc.153-, uc.158-, uc.206-, uc.274-, uc.472-, and uc.473-). Analogous BE-specific T-UCR profiles were shared by human and murine lesions. This study is the first demonstration of a role for T-UCRs in the transformation of Barretts mucosa
Modeling functional network topology following stroke through graph theory:functional reorganization and motor recovery prediction
The study of functional reorganization following stroke has been steadily growing supported by advances in neuroimaging techniques, such as functional magnetic resonance imaging (fMRI). Concomitantly, graph theory has been increasingly employed in neuroscience to model the brain's functional connectivity (FC) and to investigate it in a variety of contexts. The aims of this study were: 1) to investigate the reorganization of network topology in the ipsilesional (IL) and contralesional (CL) hemispheres of stroke patients with (motor stroke group) and without (control stroke group) motor impairment, and 2) to predict motor recovery through the relationship between local topological variations of the functional network and increased motor function. We modeled the brain's FC as a graph using fMRI data, and we characterized its interactions with the following graph metrics: degree, clustering coefficient, characteristic path length, and betweenness centrality (BC). For both patient groups, BC yielded the largest variations between the two analyzed time points, especially in the motor stroke group. This group presented significant correlations (P<0.05) between average BC changes and the improvements in upper-extremity Fugl-Meyer (UE-FM) scores at the primary sensorimotor cortex and the supplementary motor area for the CL hemisphere. These regions participate in processes related to the selection, planning, and execution of movement. Generally, higher increases in average BC over these areas were related to larger improvements in UE-FM assessment. Although the sample was small, these results suggest the possibility of using BC as an indication of brain plasticity mechanisms following stroke
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