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6.
J Nematol ; 532021.
Artigo em Inglês | MEDLINE | ID: mdl-34079952

RESUMO

In conventional coffee farming, soil fauna can be negatively affected by the intensive management practices adopted and the use of an agroforestry system (AFS) is an alternative to reduce these impacts. In coffee AFS, soil nutrition is provided mainly using organic fertilizers. This soil management favors the microbiota and can alter the population dynamics of some organisms. Our objective was to evaluate the effect of organic fertilizers on the nematode community in coffee AFS and to determine their impact on soil ecology. Soil samples were collected from three coffee AFS and a nearby Atlantic rainforest fragment. Nematodes were extracted from the samples and identified to the genus. The identified populations were compared using several community and diversity indices to determine the environmental conditions of the systems under evaluation. No differences in total abundance among nematode communities were found in the four areas evaluated. Regarding trophic groups, the coffee AFS treated with either cow manure or poultry litter favored the trophic group of bacterivores. Plant-parasitic nematodes were more abundant in soils of both the naturally fertilized coffee AFS and the Atlantic rainforest fragment. The maturity and structural indexes indicated that the Atlantic rainforest fragment and the naturally fertilized coffee AFS had similar ecological functions. On the other hand, soils fertilized with cow manure were less diverse, had higher dominance in the community, and showed less ecological stability. The nematode communities found in the AFS were similar to those seen in the forest fragment indicating that is possible to produce coffee sustainably without negatively affecting soil quality.

7.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 769-777, May-June, 2020. ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1129174

RESUMO

Canine Hip Dysplasia (CHD) is a highly prevalent articular pathological condition. In this sense, radiography becomes an important diagnostic method to determine the presence and severity of the disease. The objective was to create 3D models and their respective radiographs representing the CHD (3D AMCHD). The research was carried out in the Laboratory of 3D Educational Technologies of UFAC, under no. 23107.007273/2017-49 (CEUA/UFAC). A canine skeleton (hip bone, femurs and patellae) was used without anatomical deformities compatible with DCF (pelvis, femurs and patella), which were scanned in order to obtain the files of the base model. In these files the deformations representing the different degrees of CHD were performed. Subsequently, the 3D AMCHD files were printed, mounted and X-rayed. The 3D AMCHD represented the bone deformations of the different degrees of CHD. In the radiographs of the 3D AMCHD it was possible to observe and determine each of the bones that constituted the hip joints. This allowed to reproduce the correct positioning to represent the CHD diagnosis and establish the precise points to determine the Norberg angle. In this way, it was evidenced that the 3D AMCHD can be a possible tool to be used in the Teaching of Veterinary Medicine.(AU)


A displasia coxofemoral canina (DCF) é uma condição patológica articular de grande prevalência. Nesse sentido, a radiografia torna-se um método de diagnóstico importante para determinar a presença e a gravidade da doença. O objetivo do presente trabalho foi criar modelos 3D e suas respectivas radiografias representando a DCF (MADCF 3D). A pesquisa foi realizada no Laboratório de Tecnologias Educacionais 3D da UFAC, sob o nº. 23107.007273/2017-49 (Ceua/Ufac). Foram utilizados esqueletos caninos (pelve, fêmures e patelas) sem deformidades anatômicas compatíveis com a DCF, os quais foram digitalizados a fim de se obterem os arquivos do modelo base. Nesses arquivos foram realizadas as deformações que representavam os diferentes graus da DCF. Posteriormente, os arquivos dos MADCF 3D foram impressos, montados e radiografados. Os MADCF 3D representaram as deformações ósseas dos diferentes graus da DCF. Nas radiografias dos MADCF 3D, foi possível observar e determinar cada um dos ossos que constituíam as articulações coxofemorais. Isso permitiu reproduzir o posicionamento correto para representação do diagnóstico DCF e estabelecer os pontos precisos para determinar o ângulo de Norberg. Dessa forma, evidenciou-se que os MADCF 3D podem ser uma possível ferramenta a ser empregada no ensino de medicina veterinária.(AU)


Assuntos
Animais , Cães , Ensino , Impressão Tridimensional/instrumentação , Displasia Pélvica Canina/diagnóstico por imagem , Modelos Anatômicos , Medicina Veterinária/instrumentação , Radiografia/veterinária
8.
J Laryngol Otol ; 134(5): 398-403, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32308176

RESUMO

OBJECTIVES: To evaluate the surgical techniques, approaches, audiological outcomes and complications of endoscopic stapes surgery. METHODS: Systematic searches of the literature were performed in PubMed, Web of Science and Scopus databases, to identify studies of patients who underwent stapes surgery using endoscopic approaches and studies reporting objective post-operative hearing outcomes. The following information was extracted: surgery duration, complications, surgical technique and audiometric results. RESULTS: Fourteen studies were selected for appraisal, which included a total of 282 ears subjected to endoscopic stapes surgery. Endoscopic stapes surgery seems to provide adequate visualisation of the middle-ear structures, thereby allowing less invasive surgery and potentially equivalent audiological outcomes as compared with a traditional microscopic approach. Other advantages of endoscopic stapes surgery include decreased surgery time, a reduced need for drilling, and auditory results comparable to those of microscopic techniques. CONCLUSION: Studies have shown that endoscopic stapes surgery has similar surgical and functional advantages as compared with microscopic surgery.


Assuntos
Endoscopia/métodos , Microcirurgia/métodos , Cirurgia do Estribo/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Perda Auditiva/complicações , Perda Auditiva/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Otosclerose/complicações , Otosclerose/cirurgia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Adulto Jovem
9.
Rev Sci Instrum ; 89(10): 10I126, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399810

RESUMO

A set of gamma ray spectrometers has been designed for ITER within the Radial Gamma Ray Spectrometer (RGRS) project. The aim of this project is designing a system, integrated with the ITER radial neutron camera, which is able to measure the gamma-rays emitted from the plasma with a good energy resolution (about 1.5% at 4.44 MeV) and at high counting rates (in excess of 1 MHz). The RGRS will be able to operate both in the D phase and in the full-power DT phase and will measure gamma rays from (i) reactions between fast ions, such as α particles, and light impurities and (ii) bremsstrahlung emission generated by runaway electron interactions with both plasma bulk and tokamak walls. The RGRS detectors are arranged in nine lines of sights (able to cover a radial region with r < a/3), each featuring a large LaBr3 scintillator crystal. Due to the high neutron flux and magnetic field, several solutions have been adopted to guarantee a good signal to background ratio and MHz counting rate capabilities. The RGRS is capable to combine space and energy distribution measurements of α particles and runaway electrons, which will help the study of the fast particle physics in a burning plasma.

10.
Rev Sci Instrum ; 89(10): 10I124, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399910

RESUMO

A new gamma-ray spectrometer with MHz capabilities has been developed to measure the bremsstrahlung emission spectrum in the gamma-ray energy band generated by MeV range runaway electrons in disruption experiments at ASDEX Upgrade. Properties of the runaway electrons are inferred from the measured bremsstrahlung spectrum by a deconvolution technique, particularly with regard to their maximum energy. Changes induced to the runaway electron velocity space are unambiguously observed both in massive gas injection and resonant magnetic perturbation experiments with the detector.

11.
Rev Sci Instrum ; 89(10): 10I116, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399923

RESUMO

The JET gamma-ray cameras have been recently upgraded within the gamma-ray camera upgrade project in support of development of JET high performance deuterium plasma scenarios and in preparation of deuterium-tritium experiments. New, dedicated detectors based on a LaBr3 crystal and silicon photo-multipliers have been developed and replaced pre-existing CsI detectors in all 19 channels. The new instrument gives opportunity of making two-dimensional gamma-ray measurements with a counting rate capability exceeding 1 MCounts/s (MCps) and energy resolution better than 5% at 1.1 MeV. The upgrade is of relevance for fast ion and runaway electron physics studies in high performance deuterium discharges and also in plasmas with tritium at neutron yields in the range up to about 5 × 1017 n/s.

12.
PLoS One ; 12(11): e0187126, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29095906

RESUMO

Chemical cues from sessile hosts can attract mobile and associated organisms and they are also impotant to maintain associations and overall biodiversity, but the identity and molecular structures of these chemicals have been little explored in the marine environment. Secondary metabolites are recognized as possible chemical mediators in the association between species of Laurencia and Aplysia, but the identity of the compounds has not been established. Here, for the first time, we experimentally verify that the sesquiterpene (+)-elatol, a compound produced by the red seaweed Laurencia dendroidea, is a chemical cue attracting the associated sea hare Aplysia brasiliana. In addition to revealing the nature of the chemical mediation between these two species, we provide evidence of a chemical cue that allows young individuals of A. brasiliana to live in association with L. dendroidea. This study highlights the importance of chemical cues in Laurencia-Aplysia association.


Assuntos
Aplysia/fisiologia , Alga Marinha/química , Animais , Bioensaio , Cromatografia Gasosa-Espectrometria de Massas
13.
Supercond Sci Technol ; 30(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28360455

RESUMO

We performed a feasibility study on a high-strength Bi2-x Pb x Sr2Ca2Cu3O10-x (Bi-2223) tape conductor for high-field solenoid applications. The investigated conductor, DI-BSCCO Type HT-XX, is a pre-production version of Type HT-NX, which has recently become available from Sumitomo Electric Industries (SEI). It is based on their DI-BSCCO Type H tape, but laminated with a high-strength Ni-alloy. We used stress-strain characterizations, single- and double-bend tests, easy- and hard-way bent coil-turns at various radii, straight and helical samples in up to 31.2 T background field, and small 20-turn coils in up to 17 T background field to systematically determine the electro-mechanical limits in magnet-relevant conditions. In longitudinal tensile tests at 77 K, we found critical stress- and strain-levels of 516 MPa and 0.57%, respectively. In three decidedly different experiments we detected an amplification of the allowable strain with a combination of pure bending and Lorentz loading to ≥ 0.92% (calculated elastically at the outer tape edge). This significant strain level, and the fact that it is multi-filamentary conductor and available in the reacted and insulated state, makes DI-BSCCO HT-NX highly suitable for very high-field solenoids, for which high current densities and therefore high loads are required to retain manageable magnet dimensions.

15.
J Tissue Eng Regen Med ; 11(6): 1876-1887, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27035732

RESUMO

Wharton's jelly stem cells (WJSCs) are a potential source of transplantable stem cells in cartilage-regenerative strategies, due to their highly proliferative and multilineage differentiation capacity. We hypothesized that a non-direct co-culture system with human articular chondrocytes (hACs) could enhance the potential chondrogenic phenotype of hWJSCs during the expansion phase compared to those expanded in monoculture conditions. Primary hWJSCs were cultured in the bottom of a multiwell plate separated by a porous transwell membrane insert seeded with hACs. No statistically significant differences in hWJSCs duplication number were observed under either of the culture conditions during the expansion phase. hWJSCs under co-culture conditions show upregulations of collagen type I and II, COMP, TGFß1 and aggrecan, as well as of the main cartilage transcription factor, SOX9, when compared to those cultured in the absence of chondrocytes. Chondrogenic differentiation of hWJSCs, previously expanded in co-culture and monoculture conditions, was evaluated for each cellular passage using the micromass culture model. Cells expanded in co-culture showed higher accumulation of glycosaminoglycans (GAGs) compared to cells in monoculture, and immunohistochemistry for localization of collagen type I revealed a strong detection signal when hWJSCs were expanded under monoculture conditions. In contrast, type II collagen was detected when cells were expanded under co-culture conditions, where numerous round-shaped cell clusters were observed. Using a micromass differentiation model, hWJSCs, previously exposed to soluble factors secreted by hACs, were able to express higher levels of chondrogenic genes with deposition of cartilage extracellular matrix components, suggesting their use as an alternative cell source for treating degenerated cartilage. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Condrogênese , Regulação da Expressão Gênica , Células-Tronco Mesenquimais/metabolismo , Cartilagem Articular/citologia , Condrócitos/citologia , Técnicas de Cocultura , Humanos , Células-Tronco Mesenquimais/citologia
17.
Rev Sci Instrum ; 87(11): 11E717, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910639

RESUMO

In this work, we describe the solution developed by the gamma ray camera upgrade enhancement project to improve the spectroscopic properties of the existing JET γ-ray camera. Aim of the project is to enable gamma-ray spectroscopy in JET deuterium-tritium plasmas. A dedicated pilot spectrometer based on a LaBr3 crystal coupled to a silicon photo-multiplier has been developed. A proper pole zero cancellation network able to shorten the output signal to a length of 120 ns has been implemented allowing for spectroscopy at MHz count rates. The system has been characterized in the laboratory and shows an energy resolution of 5.5% at Eγ = 0.662 MeV, which extrapolates favorably in the energy range of interest for gamma-ray emission from fast ions in fusion plasmas.

18.
Rev Sci Instrum ; 87(11): 11E722, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910673

RESUMO

A new multichannel frequency modulated continuous-wave reflectometry diagnostic has been successfully installed and commissioned on ASDEX Upgrade to measure the plasma edge electron density profile evolution in front of the Ion Cyclotron Range of Frequencies (ICRF) antenna. The design of the new three-strap ICRF antenna integrates ten pairs (sending and receiving) of microwave reflectometry antennas. The multichannel reflectometer can use three of these to measure the edge electron density profiles up to 2 × 1019 m-3, at different poloidal locations, allowing the direct study of the local plasma layers in front of the ICRF antenna. ICRF power coupling, operational effects, and poloidal variations of the plasma density profile can be consistently studied for the first time. In this work the diagnostic hardware architecture is described and the obtained density profile measurements were used to track outer radial plasma position and plasma shape.

19.
Revista Fitos Eletrônica ; 10(4): 446-459, 2016.
Artigo em Português | MOSAICO - Saúde integrativa | ID: biblio-880588

RESUMO

Objetivou-se com este estudo, caracterizar os aspectos epidemiológicos das intoxicações humanas, ocasionadas por plantas no Estado de Pernambuco (PE), através de uma abordagem transversal e descritiva a partir de notificações obtidas no Centro de Assistência Toxicológica deste Estado, no período de 1992 a 2009. Foram analisados 214 prontuários com base nas variáveis: sexo, faixa etária, agente tóxico vegetal, sazonalidade, zona de ocorrência, local do acidente, via de exposição, circunstância, tipo de atendimento, evolução clínica. As intoxicações predominaram no sexo feminino (52,34%), faixa etária de 1 a 4 anos (42,52%), e a maioria ocorreu nos meses de fevereiro, agosto e outubro. A maioria das intoxicações foi na área urbana (74,30%), em acidentes nas residências (72,90%), através de plantas, sendo que 85% por via oral. A família Araceae foi responsável por 35,98% das intoxicações, seguida das famílias Euphorbiaceae 23,83% e Solanaceae com 5,60% dos casos. Os pacientes foram atendidos e a gravidade dos casos, em sua maioria, evoluiu para melhora de saúde, não sendo possível fazer o registro de cura, pelo fato de os mesmos deixarem o hospital sem a devida alta. Espera-se alertar os profissionais de saúde da importância das plantas, como fator de risco de intoxicação, possibilitando o estabelecimento de políticas públicas de prevenção e promoção da saúde.(AU)


The objective of this study was to characterize the epidemiological aspects of human poisoning caused by plants in the State of Pernambuco. This is a cross-sectional descriptive study from notifications obtained in the Toxicological Assistance Centre of Pernambuco (CEATOX), between 1992-2009. 214 records were analyzed using these variables: sex, age group, vegetal toxic agent, seasonality, occurrence zone locations, poisoning site, way of contamination, circumstances of poisoning, type of treatment, and the outcome. Poisoning predominated in females (52.34%) aged 1 to 4 years (42.52%) and the majority occurred in February, August and October. Most poisonings took place in the urban zone (74.30%), caused by home accidents (72.90%) by the oral ingestion of the toxic agent (85%). The family Araceae accounted for (35.98%) of poisonings, followed by Euphorbiaceae families (23.83%) and Solanaceae with (5.60%). Patients were treated and mostly evolved into health improvement, but we lack data regarding cure due to the fact that the patients left the hospital without proper medical release. We hope to alert health professionals of the importance of poisonous plants as a risk factor, enabling the establishment of new public policies for health promotion and prevention for the general public.(AU)


Assuntos
Humanos , Intoxicação por Plantas/epidemiologia , Distribuição por Idade , Brasil/epidemiologia , Estudos Transversais , Fitoterapia/efeitos adversos , Centros de Controle de Intoxicações
20.
Braz J Biol ; 74(3): 545-52, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25296201

RESUMO

Species of Plocamium are known as prolific sources of halogenated secondary metabolites exhibiting few explored ecological roles. In this study the crude extracts from specimens of P. brasiliense collected in two distinct places, Enseada do Forno and Praia Rasa, Búzios, Estado do Rio de Janeiro, were evaluated as defense against the sea urchin Lytechinus variegatus and the crab Acanthonyx scutiformis. These specimens produce a similar amount of crude extract and also halogenated monoterpene compound-types, but individuals of P. brasiliense from Praia Rasa exhibit a major compound representing about 59% of the total chemicals. Natural concentrations of the crude extracts obtained from both specimens of P. brasiliense significantly inhibited the herbivory by the sea urchin L. variegatus, but had no significant effect on the feeding by A. scutiformis, a crab commonly associated to chemically defended host. Crude extract from P. brasiliense collected at Praia Rasa was more efficient as defense against L. variegatus than that crude extract from populations of this alga from Enseada do Forno, probably due to presence of a major secondary metabolite. These two studied population live under different environmental conditions, but they are only about 30 Km apart. However, it is impossible to affirm that environmental characteristics (abiotic or biotic) would be responsible for the difference of defensive potential found in the two populations of P. brasiliense studied here. Further genetic studies will be necessary to clarify this question and to explain why populations of a single species living in different but close locations can exhibit distinct chemicals.


Assuntos
Braquiúros/fisiologia , Herbivoria/fisiologia , Plocamium/química , Ouriços-do-Mar/fisiologia , Animais , Braquiúros/classificação , Fenômenos Fisiológicos Vegetais/fisiologia , Ouriços-do-Mar/classificação
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