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1.
Nanotechnology ; 35(6)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38009501

RESUMO

In this work, we present a theoretical model for domain wall (DW) oscillations in a curved magnetic nanowire with a constant curvature under the action of a uniaxial magnetic field. Our results show that the DW dynamics can be described as that of the mechanical pendulum, and both the NW curvature and the external magnetic field influence its oscillatory frequency. A comparison between our theoretical approach and experimental data in the literature shows an excellent agreement. The results presented here can be used to design devices demanding the proper control of the DW oscillatory motion in NWs.

2.
Nanotechnology ; 34(16)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36689765

RESUMO

Three dimensional magnetic textures are a cornerstone in magnetism research. In this work, we analyze the stabilization and dynamic response of a magnetic hopfion hosted in a toroidal nanoring with intrinsic Dzyaloshinskii-Moriya interaction simulating FeGe. Our results evidence that unlike their planar counterparts, where perpendicular magnetic anisotropies are necessary to stabilize hopfions, the shape anisotropy originated on the torus symmetry naturally yields the nucleation of these topological textures. We also analyze the magnetization dynamical response by applying a magnetic field pulse to differentiate among several magnetic patterns. Finally, to understand the nature of spin wave modes, we analyze the spatial distributions of the resonant mode amplitudes and phases and describe the differences among bulk and surface modes. Importantly, hopfions lying in toroidal nanorings present a non-circularly symmetric poloidal resonant mode, which is not observed in other systems hosting hopfions.

3.
Arq. bras. med. vet. zootec. (Online) ; 73(5): 1187-1193, Sept.-Oct. 2021. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345279

RESUMO

This research article aims to evaluate the effect of total replacement of corn by soybean meal and urea on intake and apparent digestibility of dry matter and its components, production and composition of milk and feeding behavior of lactating cows grazing, with intermittent stocking Mombaça grass (Megathyrsus maximus cv. Mombaça). Twelve milking cows were distributed in a triple 4 x 4 latin square. Experimental treatments consisted of four soybean meal replacement levels by corn more urea (0; 33; 66; 100%). The grass has an average content of crude protein and neutral detergent fiber of 19% and 59%, respectively. The replacement of soybean meal by corn and urea did not affect the intake and digestibility of nutrients. A linear reduction of milk production was observed, but there was no change in milk production corrected to 4.0% of fat. The milk components (g/kg) of fat, protein, lactose, and total solids were not altered, as well as feeding behavior. Under the conditions of this study, the replacement of the diets is suitable for crossbred dairy cows in lactation third medium, producing in average of 12.5 kg/day-1 when kept in quality pastures.(AU)


Este artigo de pesquisa tem como objetivo avaliar o efeito da substituição total do milho pelo farelo de soja e ureia sobre o consumo e a digestibilidade aparente da matéria seca e de seus componentes, a produção e a composição do leite e o comportamento alimentar de vacas em lactação mantidas em pastos capim-mombaça (Megathyrsus maximus cv. Mombaça) manejado sob lotação intermitente. Doze vacas em lactação foram distribuídas em um quadrado latino triplo 4 x 4. Os tratamentos experimentais consistiram de quatro níveis de substituição do farelo de soja pelo milho mais ureia (0; 33; 66; 100%). O capim-mombaça apresentou um teor médio de proteína bruta e de fibra em detergente neutro de 19% e 59%, respectivamente. A substituição do farelo de soja por milho e ureia não afetou o consumo e a digestibilidade dos nutrientes. Observou-se redução linear da produção de leite, mas não houve alteração na produção de leite corrigida para 4,0% de gordura. Os componentes do leite (g/kg): gordura, proteína, lactose e sólidos totais não foram alterados, assim como o comportamento ingestivo dos animais. Nas condições deste estudo, a substituição total do milho pelo farelo de soja e ureia nas dietas é adequada para vacas mestiças leiteiras em terço médio de lactação, produzindo, em média, 12,5 kg / dia-1 quando mantidas em pastagens de qualidade.(AU)


Assuntos
Animais , Feminino , Bovinos , Glycine max , Ureia , Zea mays , Dieta/veterinária , Ração Animal , Proteínas do Leite/análise
4.
J Phys Condens Matter ; 33(26)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-33902016

RESUMO

When the skyrmion dynamics beyond the particle-like description is considered, this topological structure can deform due to a self-induced field. In this work, we perform Monte Carlo simulations to characterize the skyrmion deformation during its steady movement. In the low-velocity regime, the deformation in the skyrmion shape is quantified by an effective inertial mass, which is related to the dissipative force. When skyrmions move faster, the large self-induced deformation triggers topological transitions. These transitions are characterized by the proliferation of skyrmions and a different total topological charge, which is obtained as a function of the skyrmion velocity. Our findings provide an alternative way to describe the dynamics of a skyrmion that accounts for the deformations of its structure. Furthermore, such motion-induced topological phase transitions make it possible to control the number of ferromagnetic skyrmions through velocity effects.

5.
Nanotechnology ; 32(17): 175702, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33370722

RESUMO

Magnetic skyrmions are quasiparticle-like textures that are topologically different from a single domain magnetization state. Their topological protection, combined with the low current density needed to move them, make these objects relevant to be used as information storage structures. In such a context, the analysis of the interactions between skyrmions is interesting and relevant for future applications. In this work, through micromagnetic simulations and numerical calculations, we studied the interaction between two skyrmions living on different parallel ferromagnetic racetracks connected by an exchange-like interaction. The upper and lower racetracks are separated by a height offset and the interaction between the upper and the lower skyrmion is analyzed in terms of the magnetic and geometrical parameters. Three states are predicted, as a function of these parameters: scattered or free skyrmions, bound skymions, and annihilated skyrmions. Our results, presented in a phase diagram, demonstrate that even in the case here called free skyrmions, there is a small and brief interaction when both are close enough, but the skyrmion in the top layer does not drag the skyrmion in the bottom layer. For bound skyrmions, both keep linked during larger times. In the latter case, there are strong changes in the velocity of the skyrmions induced by the effect of a higher effective mass when both are coupled.

6.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1449-1457, July-Aug. 2020. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1131489

RESUMO

This study aimed to assess different prebiotic concentrations and principles, in addition to calcium butyrate, aiming to replace colistin as a growth promoter. The sample consisted of 120 piglets weaned at 22 days old with mean initial weight of 5.475 ± 0.719kg. The animals were assigned to random blocks in six treatments corresponding to the use of the following dietary additives: T1) colistin (40 ppm); T2) ß-glucan/mannan-oligosaccharides (0.2%); T3) calcium butyrate (0.1%); T4) ß-glucan/mannan-oligosaccharides (0.1%) + fructooligosaccharides (0.01%) + galactooligosaccharides (0.09%); T5) ß-glucan/mannan-oligosaccharides (0.1%) + fructooligosaccharides (0.03%) + galactooligosaccharides (0.07%); and T6) ß-glucan/mannan-oligosaccharides (0.1%) + fructooligosaccharides (0.05%) + galactooligosaccharides (0.05%). The results showed no difference among treatments for the performance parameters in any of the phases evaluated. For diarrhea incidence and intensity, the results indicated that the treatments with alternative additives had similar effects as the group treated with colistin. A significant difference was found for the profile of propionic acid (0.23% colistin and 0.32%, 0.36%, 0.37% additives) and total fatty acids (0.67% colistin and 0.97% additives) values in the caecum. The supplementation with different compositions and concentrations of prebiotics and butyric acid may viably replace colistin in controlling diarrhea and modulating volatile fatty acid production in the caecum.(AU)


O objetivo deste trabalho foi avaliar as diferentes concentrações e princípios de prebióticos e do butirato de sódio, visando substituir a colistina como promotor de crescimento. Foram utilizados 120 leitões, desmamados aos 22 dias de idade, com peso médio inicial de 5,475 ± 0,719kg. Os animais foram distribuídos em blocos ao acaso, em seis tratamentos, que corresponderam ao uso dos seguintes aditivos dietéticos: T1) colistina (40ppm); T2) ß-glucanos/mananoligossacarídeos (0,2%); T3) butirato de cálcio (0,1%); T4) ß-glucanos/mananoligossacarídeos (0,1%) + frutoligossacarídeos (0,01%) + galactoligossacarídeos (0,09%); T5) ß-glucanos/mananoligossacarídeos (0,1%) + frutoligossacarídeos (0,03%) + galactoligossacarídeos (0,07%); e T6) ß-glucanos/mananoligossacarídeos (0,1%) + frutoligossacarídeos (0,05%) + galactoligossacarídeos (0,05%). Os resultados mostraram que não houve diferença entre os tratamentos para nenhum dos parâmetros de desempenho em nenhuma das fases avaliadas. Para a incidência e a intensidade de diarreia, os resultados apontam que os tratamentos com os aditivos alternativos apresentaram efeitos semelhantes aos do grupo tratado com colistina. Foi encontrada diferença significativa para perfil dos ácidos graxos propiônicos (0,23% colistina e 0,32%, 0,36%, 0,37% aditivos) e ácidos totais (0,67% colistina e 0,97% aditivos) no ceco. A suplementação com diferentes composições e concentrações de prebióticos e do ácido butírico pode substituir a colistina de forma viável no controle da diarreia e na modulação da produção volátil de ácidos graxos no ceco.(AU)


Assuntos
Animais , Suínos/crescimento & desenvolvimento , Ácido Butírico/administração & dosagem , Prebióticos/administração & dosagem , Aumento de Peso , Aditivos Alimentares/administração & dosagem
7.
Br J Dermatol ; 183(1): 146-154, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31605618

RESUMO

BACKGROUND: Skin tears are acute wounds that are frequently misdiagnosed and under-reported. A standardized and globally adopted skin tear classification system with supporting evidence for diagnostic validity and reliability is required to allow assessment and reporting in a consistent way. OBJECTIVES: To measure the validity and reliability of the International Skin Tear Advisory Panel (ISTAP) Classification System internationally. METHODS: A multicountry study was set up to validate the content of the ISTAP Classification System through expert consultation in a two-round Delphi procedure involving 17 experts from 11 countries. An online survey including 24 skin tear photographs was conducted in a convenience sample of 1601 healthcare professionals from 44 countries to measure diagnostic accuracy, agreement, inter-rater reliability and intrarater reliability of the instrument. RESULTS: A definition for the concept of a 'skin flap' in the area of skin tears was developed and added to the initial ISTAP Classification System consisting of three skin tear types. The overall agreement with the reference standard was 0·79 [95% confidence interval (CI) 0·79-0·80] and sensitivity ranged from 0·74 (95% CI 0·73-0·75) to 0·88 (95% CI 0·87-0·88). The inter-rater reliability was 0·57 (95% CI 0·57-0·57). The Cohen's Kappa measuring intrarater reliability was 0·74 (95% CI 0·73-0·75). CONCLUSIONS: The ISTAP Classification System is supported by evidence for validity and reliability. The ISTAP Classification System should be used for systematic assessment and reporting of skin tears in clinical practice and research globally. What's already known about this topic? Skin tears are common acute wounds that are misdiagnosed and under-reported too often. A skin tear classification system is needed to standardize documentation and description for clinical practice, audit and research. What does this study add? The International Skin Tear Advisory Panel Classification System was psychometrically tested in 1601 healthcare professionals from 44 countries. Diagnostic accuracy was high when differentiating between type 1, 2 and 3 skin tears using a set of validated photographs.


Assuntos
Lacerações , Lesões dos Tecidos Moles , Humanos , Lacerações/diagnóstico , Reprodutibilidade dos Testes , Pele/lesões , Inquéritos e Questionários
8.
Arq. bras. med. vet. zootec. (Online) ; 70(4): 1266-1274, jul.-ago. 2018. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-946529

RESUMO

Objetivou-se com este estudo avaliar os efeitos da substituição total do farelo de soja por milho e ureia sobre consumo e digestibilidade aparente da matéria seca, perfil metabólico proteico e balanço de nitrogênio de vacas mestiças em lactação em pastejo, com lotação intermitente de capim-mombaça (Panicum maximum). Foram utilizadas 12 vacas mestiças em lactação, com peso corporal médio inicial de 473,0+45,0kg, período de lactação médio de 95,0+42,2 dias e produção de leite de média inicial de 14,1+1,9kg/dia. As vacas eram primíparas e multíparas, mestiças de Girolando, Pardo-Suíço e Jersey. Os tratamentos consistiram em quatro níveis de substituição do farelo de soja por milho e ureia (0; 33; 66; 100% na matéria seca - MS). O capim-mombaça apresentou teor médio de proteína bruta e fibra em detergente neutro de 19 e 59% na MS, respectivamente. A substituição do farelo de soja por milho e ureia não alterou o consumo e a digestibilidade aparente da MS. As concentrações de ureia e N-ureico plasmáticos foram alteradas pela substituição do farelo de soja por milho e ureia. O balanço de nitrogênio foi positivo e não foi alterado com as substituições. Para vacas mestiças produzindo, em média, 12,5kg/dia e mantidas em pasto de qualidade, pode se substituir totalmente o farelo de soja por milho e ureia.(AU)


The objective of this study was to evaluate the effects of total replacement of corn by soybean meal and urea on intake and apparent digestibility of dry matter, protein metabolic profile, and nitrogen balance of lactating crossbred cows grazing with intermittent stocking Mombasa grass (Panicum maximum). Twelve milking cows were distributed in a triple 4 x 4 latin design, with a mean initial body weight of 473,0+45,0kg, average lactation period of 95,0+42,2 days and milk production of initial mean of 14,1+1,9kg/day. Cows were primiparous and multiparous. The treatments consisted of four levels of substitution of soybean meal for corn and urea (0; 33; 66; 100% in dry matter - DM). The Mombasa grass showed an average content of crude protein and neutral detergent fiber of 19 and 59% in DM, respectively. The concentrations of urea and plasma urea nitrogen were altered by replacing soybean meal with corn and urea. Protein metabolic profile was changed with the replacement of soybean meal by corn and urea. The nitrogen balance was positive and has not changed with the replacements. For mixed-race cows producing an average of 12.5kg/day and kept in good-quality pastures, one can replace soybean meal totally with corn and urea.(AU)


Assuntos
Animais , Feminino , Bovinos , Bovinos/metabolismo , Lactação , Ureia/análise , Zea mays/química
9.
Arq. bras. med. vet. zootec. (Online) ; 70(6): 1833-1839, nov.-dez. 2018. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-970535

RESUMO

Objetivou-se, com a presente pesquisa, avaliar a viabilidade de Aspergillus spp. com potencial probiótico durante o armazenamento e diante da pressão da microbiota autóctone, bem como a tolerância aos principais ácidos graxos da fermentação ruminal. Verificou-se também a inocuidade micotoxicológica desses isolados fúngicos cultivados em meio de cultivo sólido. Foram avaliados 20 isolados de Aspergillus spp., provenientes do trato gastrointestinal de bovinos criados em Urochloa decumbens lignificada. Esses fungos foram identificados por análise de sequências do DNAr e foram selecionados por apresentarem expressivo potencial celulolítico. O método vapor de amônia foi utilizado para detecção de cepas produtoras de micotoxinas. Os isolados foram avaliados quanto à viabilidade de crescimento em fluido ruminal por até 96 horas e estocagem em condições ambientais. Observou-se que os fungos avaliados não produziram aflatoxinas e que 95% dos isolados apresentaram resistência aos ácidos ruminais. Dois isolados, selecionados a partir das análises anteriores, apresentaram viabilidade sob a pressão da microbiota autóctone e de metabólitos do ecossistema ruminal e permanecem viáveis por, no mínimo, dois anos. Conclui-se que os isolados do gênero Aspergillus selecionados nesta pesquisa apresentam características fisiológicas para serem utilizados com aditivos microbianos ou probióticos para o ambiente ruminal.(AU)


The aims in this study were to evaluate the viability of Aspergillus spp. with probiotic potential during storage, pressure of autochthonous microbiota and tolerance to the main fatty acids of ruminal fermentation. The mycotoxicological safety was also verified. Twenty isolates from the gastrointestinal tract of cattle raised in lignified Urochloa decumbens were identified by rDNA sequence analysis and were previously selected because they showed significant cellulolytic potential. The ammonia vapor method was used to detect the production of mycotoxins. The isolates were evaluated for viability of ruminal fluid growth for up to 96 hours and storage under environmental conditions. The evaluated fungi did not produce aflatoxins, and 95% of them had resistance to ruminal acids. Two isolates, selected according these tests, presented viability on autochthonous microbiota pressure and metabolites from the ruminal ecosystem and remain viable for at least two years. In this research, the selected Aspergillus spp. isolates present physiological characteristics to be used with microbial additives or probiotic.(AU)


Assuntos
Animais , Bovinos , Aspergillus , Bovinos/microbiologia , Probióticos/toxicidade , Micotoxinas , Trato Gastrointestinal/microbiologia
10.
Microb Cell Fact ; 16(1): 155, 2017 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-28927409

RESUMO

BACKGROUND: Lactobacillus species produce biosurfactants that can contribute to the bacteria's ability to prevent microbial infections associated with urogenital and gastrointestinal tracts and the skin. Here, we described the biological and physicochemical properties of biosurfactants produced by Lactobacillus jensenii P6A and Lactobacillus gasseri P65. RESULTS: The biosurfactants produced by L. jensenii P6A and L. gasseri P65 reduced the water surface tension from 72 to 43.2 mN m-1 and 42.5 mN m-1 as their concentration increased up to the critical micelle concentration (CMC) values of 7.1 and 8.58 mg mL-1, respectively. Maximum emulsifying activity was obtained at concentrations of 1 and 5 mg mL-1 for the P6A and P65 strains, respectively. The Fourier transform infrared spectroscopy data revealed that the biomolecules consist of a mixture of carbohydrates, lipids and proteins. The gas chromatography-mass spectrum analysis of L. jensenii P6A biosurfactant showed a major peak for 14-methypentadecanoic acid, which was the main fatty acid present in the biomolecule; conversely, eicosanoic acid dominated the biosurfactant produced by L. gasseri P65. Although both biosurfactants contain different percentages of the sugars galactose, glucose and ribose; rhamnose was only detected in the biomolecule produced by L. jensenii P6A. Emulsifying activities were stable after a 60-min incubation at 100 °C, at pH 2-10, and after the addition of potassium chloride and sodium bicarbonate, but not in the presence of sodium chloride. The biomolecules showed antimicrobial activity against clinical isolates of Escherichia coli and Candida albicans, with MIC values of 16 µg mL-1, and against Staphylococcus saprophyticus, Enterobacter aerogenes and Klebsiella pneumoniae at 128 µg mL-1. The biosurfactants also disrupted preformed biofilms of microorganisms at varying concentrations, being more efficient against E. aerogenes (64%) (P6A biosurfactant), and E. coli (46.4%) and S. saprophyticus (39%) (P65 biosurfactant). Both strains of lactobacilli could also co-aggregate pathogens. CONCLUSIONS: This report presents the first characterization of biosurfactants produced by L. jensenii P6A and L. gasseri P65. The antimicrobial properties and stability of these biomolecules indicate their potential use as alternative antimicrobial agents in the medical field for applications against pathogens that are responsible for infections in the gastrointestinal and urogenital tracts and the skin.


Assuntos
Lactobacillus gasseri/metabolismo , Tensoativos/química , Tensoativos/metabolismo , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Infecções Bacterianas/microbiologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Lactobacillus/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/farmacologia
11.
Microsc Res Tech ; 80(8): 831-837, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28370895

RESUMO

Piper solmsianum C.DC., which is popularly known as pariparoba, is a shrub that measures 1-3 m in height and it inhabits areas with wet tropical soils. The objective of this study was to analyze the leaf and stem anatomy using light microscopy, scanning electron micrographs, and energy-dispersive X-ray spectroscopy in order to provide information for species identification. The anatomical profile showed the following main microscopic markers: hypostomatic leaf; hypodermis layer on both sides; pearl glands; biconvex midrib shape; five collateral vascular bundles in open arc with the central bundle larger than the others; circular stem shape; collateral vascular bundles arranged in two rings; sinuous sclerenchymatic sheath in the pith; secretory idioblasts; and starch grains in the mesophyll, in the ground parenchyma of the midrib, petiole, and in the stem; and six morphotypes of calcium oxalate crystals (styloids, cuneiform, tabular crystal rosettes, cuneiform crystal rosettes, elongated square dipyramids, as well as very elongated square dipyramids).


Assuntos
Piper/ultraestrutura , Folhas de Planta/ultraestrutura , Caules de Planta/ultraestrutura , Microscopia Eletrônica de Varredura , Piper/química , Folhas de Planta/química , Caules de Planta/química , Espectrometria por Raios X
12.
Genet Mol Res ; 16(1)2017 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-28218783

RESUMO

In the present study, we demonstrated the in vitro activity of endophytic phosphate-solubilizing bacteria (PSB). Fifty-five endophytic PSB that were isolated from sap, leaves, and roots of maize were tested for their ability to solubilize tricalcium phosphate and produce organic acid. Partial sequencing of the 16S rRNA-encoding gene showed that the isolates were from the genus Bacillus and different species of Enterobacteriaceae. The phosphate solubilization index on solid medium and phosphate solubilization in liquid medium varied significantly among the isolates. There was a statistically significant difference (P ≤ 0.05) for both, the values of phosphate-solubilizing activity and pH of the growth medium, among the isolates. Pearson correlation was statistically significant (P ≤ 0.05) between P-solubilization and pH (R = -0.38), and between the gluconic acid production and the lowering of the pH of the liquid medium at 6 (R = 0.28) and 9 days (R = 0.39). Gluconic acid production was prevalent in all the PSB studied, and Bacillus species were most efficient in solubilizing phosphate. This is the first report on the characterization of bacterial endophytes from maize and their use as potential biofertilizers. In addition, this may provide an alternative strategy for improving the phosphorus acquisition efficiency of crop plants in tropical soils.


Assuntos
Bactérias/classificação , Endófitos/classificação , Fosfatos/metabolismo , Zea mays/microbiologia , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , DNA Bacteriano/genética , DNA Ribossômico/genética , Endófitos/genética , Endófitos/isolamento & purificação , Endófitos/metabolismo , Gluconatos/metabolismo , Filogenia , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Microbiologia do Solo
13.
Braz. j. biol ; 76(4): 871-877, Oct.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-828081

RESUMO

Abstract Concentrations of ten elements (Cd, Cr, Cu, Fe, Ni, Pb, Se, Sr, V and Zn) were determinate in muscle tissues of 13 fish species from Aratu Bay, Bahia, Brazil by inductively coupled plasma optical emission spectrometry. The accuracy and precision of our results were checked by using two certified reference materials: BCR-422 cod muscle and SRM 1566b oyster tissue. The average trace element concentrations in the fish species varied in the following ranges, in μg g–1: 0.03-0.8 for Cr; 2.0-33.7 for Cu, 2.4-135.1 for Fe, 1.6-25.6 for Se; 1.6-35.1 for Sr; and 2.8-40.5 for Zn. The Diaptereus rhombeus (carapeba) specie presented the highest concentrations of Se, Cu and Fe. Chromium and Se were present at levels above the limit of tolerance allowed by the National Agency of Sanitary Vigilance (ANVISA). The results were also evaluated using the multivariate analysis techniques: principal component analysis (PCA) and hierarchical cluster analysis (HCA).


Resumo Foram determinadas as concentrações de dez elementos (Cd, Cr, Cu, Fe, Ni, Pb, Se, Sr, V and Zn) em tecidos de músculos de treze espécies de peixes da Baía de Aratu, Bahia, Brasil, utilizando a espectrometria de emissão ótica com plasma indutivamente acoplado. A precisão e exatidão dos resultados foram analisadas utilizando dois materiais de referência certificada: BCR-422 cod muscle e o SRM 1566b oyster tissue. A concentração média dos elementos traço nas espécies de peixes variaram nas seguintes faixas, em μg g−1: Cr = 0,03-0,8; Cu = 2,0-33,7, Fe = 2,4-135,1, Se = 1,6-25,6; Sr = 1,6-35,1; Zn = 2.8-40.5. A espécie Diaptereus rhombeus (carapeba) apresentou as maiores concentrações de Se, Cu e Fe. Cromo e Se apresentaram níveis acima do limite de tolerância estabelecido pela Agência Nacional de Vigilância Sanitária (ANVISA). Os resultados ainda foram avaliados usando técnicas de análises multivariadas: análise de componente principal (PCA) e análise de agrupamento hierárquico (HCA).


Assuntos
Animais , Oligoelementos/análise , Alimentos Marinhos/análise , Peixes , Brasil , Contaminação de Alimentos , Análise por Conglomerados , Baías , Análise de Componente Principal , Metais/análise , Músculos/química
14.
Braz J Biol ; 76(4): 871-877, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27143069

RESUMO

Concentrations of ten elements (Cd, Cr, Cu, Fe, Ni, Pb, Se, Sr, V and Zn) were determinate in muscle tissues of 13 fish species from Aratu Bay, Bahia, Brazil by inductively coupled plasma optical emission spectrometry. The accuracy and precision of our results were checked by using two certified reference materials: BCR-422 cod muscle and SRM 1566b oyster tissue. The average trace element concentrations in the fish species varied in the following ranges, in µg g-1: 0.03-0.8 for Cr; 2.0-33.7 for Cu, 2.4-135.1 for Fe, 1.6-25.6 for Se; 1.6-35.1 for Sr; and 2.8-40.5 for Zn. The Diaptereus rhombeus (carapeba) specie presented the highest concentrations of Se, Cu and Fe. Chromium and Se were present at levels above the limit of tolerance allowed by the National Agency of Sanitary Vigilance (ANVISA). The results were also evaluated using the multivariate analysis techniques: principal component analysis (PCA) and hierarchical cluster analysis (HCA).


Assuntos
Peixes , Alimentos Marinhos/análise , Oligoelementos/análise , Animais , Baías , Brasil , Análise por Conglomerados , Contaminação de Alimentos , Metais/análise , Músculos/química , Análise de Componente Principal
15.
Braz J Biol ; 76(1): 194-204, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26909636

RESUMO

In this study, concentrations of trace elements in tissues of shrimp species (Litopenaeus vannamei) from farming and zone natural coastal located in the northeastern Brazil were investigated. The elements determination was performed by optical emission spectrometry with inductively coupled plasma (ICP OES). The following ranges of concentrations in the tissues were obtained in µg g-1 dry weight: Al: 13.4-886.5, Cd: 0.93-1.80; Cu: 24.8-152; Fe: 3.2-410.9; Mn: 0.36-24.4; Se: 0.094-9.81 and Zn: 20.3-109.4. The shrimp muscle can be a good iron source (about 88.9 mg-1g dry weight). The distribution of Se concentration in tissues showed much variation between locations, and the concentration levels found in shrimp muscles of wild samples were high, where its levels in 67% of muscle and 50% of others tissues samples exceeded the ANVISA limit, indicating evidence of selenium bioaccumulation. Significant correlation was observed between the following pairs of elements: Fe-Zn (r= -0.70), Mn-Cu (r= -0.74), Se-Cu (r= -0.68), Se-Mn (r= 0.82) in the muscles; Fe-Al (r= 0.99), Mn-Al (r= 0.62), Mn-Fe (r= 0.62), Se-Al (r = 0.88), Se-Fe (r= 0.87), Se-Mn (r= 0.58) in the exoskeleton and Cu-Zn (r = 0.68), Al-Cu (r= 0.88), Fe-Cu (r= 0.95) and Fe-Al (r= 0.97) in the viscera.


Assuntos
Penaeidae/fisiologia , Oligoelementos/metabolismo , Animais , Aquicultura , Brasil , Espectrofotometria Atômica , Distribuição Tecidual
16.
Braz. j. biol ; 76(1): 194-204, Feb. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-774517

RESUMO

Abstract In this study, concentrations of trace elements in tissues of shrimp species (Litopenaeus vannamei) from farming and zone natural coastal located in the northeastern Brazil were investigated. The elements determination was performed by optical emission spectrometry with inductively coupled plasma (ICP OES). The following ranges of concentrations in the tissues were obtained in µg g–1 dry weight: Al: 13.4-886.5, Cd: 0.93-1.80; Cu: 24.8-152; Fe: 3.2-410.9; Mn: 0.36-24.4; Se: 0.094-9.81 and Zn: 20.3-109.4. The shrimp muscle can be a good iron source (about 88.9 mg–1g dry weight). The distribution of Se concentration in tissues showed much variation between locations, and the concentration levels found in shrimp muscles of wild samples were high, where its levels in 67% of muscle and 50% of others tissues samples exceeded the ANVISA limit, indicating evidence of selenium bioaccumulation. Significant correlation was observed between the following pairs of elements: Fe-Zn (r= –0.70), Mn-Cu (r= –0.74), Se-Cu (r= –0.68), Se-Mn (r= 0.82) in the muscles; Fe-Al (r= 0.99), Mn-Al (r= 0.62), Mn-Fe (r= 0.62), Se-Al (r = 0.88), Se-Fe (r= 0.87), Se-Mn (r= 0.58) in the exoskeleton and Cu-Zn (r = 0.68), Al-Cu (r= 0.88), Fe-Cu (r= 0.95) and Fe-Al (r= 0.97) in the viscera.


Resumo Esse estudo teve como objetivo avaliar as concentrações de elementos traço em tecidos da espécie de camarão Litopenaeus vannamei coletadas da zona costeira e de carciniculturas localizadas no nordeste do Brasil. Os elementos químicos foram determinados por espectrômetro de emissão óptica com plasma indutivamente acoplado (ICP OES). Foram encontradas as seguintes faixas de concentrações desses elementos nos tecidos (em mg g–1 peso seco): Al: 13,4-886,5; Cd: 0,93-1,80; Cu: 24,8-152; Fe: 3,2-4109; Mn: 0,36-24,4; Se: 0,094-9,81 and Zn: 20,3-109,4. O músculo do camarão investigado pode ser uma boa fonte de ferro (cerca de 88.9 mg-1g peso seco). A distribuição da concentração de Se nos tecidos apresentou muita variação entre as localidades, com níveis acima do estabelecido pela ANVISA para 67% dos musculos e 50% dos outros tecidos investigados, indicando evidências de bioacumulação do selênio. Houve correlações significativas entre os seguintes pares de elementos:: Fe-Zn (r= –0,70), Mn-Cu (r= –0,74), Se-Cu (r= –0,68), Se-Mn (r= 0,82) nos músculos, Fe-Al (r= 0,99), Mn-Al e Mn-Fe (r= 0,62), Se-Al (r = 0,88), Se-Fe (r= 0,87), Se-Mn (r= 0,58) no exoesqueleto e Cu-Zn (r = 068), Al-Cu (r= 0,88), Fe-Cu (r= 0,95) and Fe-Al (r= 0,97) nas vísceras.


Assuntos
Animais , Penaeidae/fisiologia , Oligoelementos/metabolismo , Aquicultura , Brasil , Espectrofotometria Atômica , Distribuição Tecidual
17.
Rev. bras. plantas med ; 18(1): 89-95, jan.-mar. 2016. graf
Artigo em Português | LILACS | ID: lil-780031

RESUMO

RESUMO Tanacetum vulgare L., conhecida popularmente como catinga-de-mulata, é utilizada na medicina tradicional como vermífugo, digestivo e emenagogo. Objetivou-se analisar a morfoanatomia de folhas e caules dessa espécie medicinal com vistas ao controle da qualidade. Foram utilizadas técnicas usuais de microscopia de luz e eletrônica de varredura. As folhas são compostas, pinatissectas e anfiestomáticas. Tricomas tectores flageliformes simples e glandulares capitados são observados. A nervura central tem formato biconvexo, o pecíolo é côncavo-convexo, a ráque é plano-convexa e o caule é arredondado. Feixes vasculares colaterais, calotas de fibras perivasculares e colênquima lamelar estão presentes na folha e no caule. Os caracteres morfoanatômicos evidenciados contribuem na identificação do táxon e fornecem subsídios farmacobotânicos para o controle da qualidade de drogas vegetais e fitoterápicos.


ABSTRACT Tanacetum vulgare L., popularly known as tansy, is used in traditional medicine as a vermifuge, digestive and emmenagogue. This study aimed to analyze the morphoanatomical leaves and stems of this medicinal plant in order to control the quality. Usual techniques of light and scanning electron microscopy were used. The leaves are composed, pinatissect and amphistomatic. Simple and flagelliform non- glandular trichomes and capitate glandular trichomes are observed. The midrib has biconvex shape, the petiole is concavo-convex, the rachis is plano-convex, and the stem is rounded. Collateral vascular bundles, perivascular fiber caps and laminar collenchyma are encountered in the leaves and stems. Evidenced the morphological and anatomical features contribute to the identification of the taxon and provide pharmacobotanical data for the quality control of herbal drugs.


Assuntos
/análise , Folhas de Planta/classificação , Controle de Qualidade , Asteraceae/classificação
18.
Bioresour Technol ; 146: 261-266, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23941709

RESUMO

Yeasts capable of growth on xylose were isolated from macaúba (Acrocomia aculeata) fruit, a Brazilian palm tree with great potential for use as biodiesel feedstock production. Candida boidinii UFMG14 strain achieved the highest ethanol production (5 g/L) and was chosen to ferment macaúba presscake hemicellulosic hydrolysate (MPHH). The MPHH was produced by the first time in this work and the resultant fivefold concentrate showed considerable sugar content (52.3 and 34.2 g/L xylose and glucose, respectively) and low furfural (0.01 g/L) and hydroxymethylfurfural (0.15 g/L) concentrations. C. boidinii UFMG14 fermentation was evaluated in supplemented and non-supplemented MPHH containing either 10 or 25 g/L of xylose. The maximum ethanol production (12 g/L) was observed after 48 h of fermentation. The ethanol yield was significantly affected by supplementation and concentration of MPHH while ethanol productivity was affected only by MPHH concentration. This is the first study demonstrating theC. boidinii potential for ethanol production from hemicellulose byproducts.


Assuntos
Biocombustíveis , Candida/metabolismo , Etanol/química , Frutas/química , Polissacarídeos/química , Xilose/química , Brasil , Fermentação , Glucose , Fatores de Tempo , Árvores , Xilitol/biossíntese
19.
Arq. bras. med. vet. zootec ; 65(2): 610-618, abr. 2013. tab
Artigo em Português | LILACS | ID: lil-673142

RESUMO

Avaliou-se o efeito da utilização de níveis crescente de minerais orgânicos sobre a qualidade externa e interna de ovos e a resistência de ossos da tíbia de poedeiras semi-pesadas. Foram utilizadas 256 aves, com idade inicial de 30 semanas, distribuídas em 64 gaiolas perfazendo quatro aves por gaiola em delineamento inteiramente ao acaso. Os tratamentos consistiram da inclusão de minerais inorgânicos ou níveis crescentes de orgânicos na dieta basal das poedeiras, resultando em quatro tratamentos. Foram avaliados peso do ovo (g), gravidade específica, peso (g) e espessura (mm) da casca, altura do albúmen (mm), unidade Haugh, peso da gema (g) e do albúmen (g) e resistência óssea (kg). Houve diferença significativa (P>0,05) entre as médias para peso do ovo e do albúmen. O fornecimento de dietas suplementadas com minerais orgânicos, em nível intermediário resultou na produção de ovos mais pesados, com maior peso de albúmen, e na manutenção das demais características de qualidade externa e interna dos ovos e de resistência óssea.


The effect of increasing levels of organic minerals on the external and internal quality of eggs and tibia bone strength of brown-egg laying hens was studied. A total of 256, 30-week old was equally distributed in 64 cages in a total of four birds per cage in a completely randomized experimental design. The dietary treatments consisted of inorganic or increasing levels of organic minerals in the diets of laying hens, resulting in four treatments. Egg weight (g), specific gravity, shell weight and thickness (mm), albumen height (mm), Haugh unit, yolk weight and albumen (g) and bone strength (kg) were evaluated. A significant difference (P<0.05) among treatment means for egg weight and albumen was found. Intermediate inclusion levels of organic minerals resulted in the production of heavier eggs, with higher albumen weight and maintenance of the other characteristics of internal and external quality of eggs and bone strength.


Assuntos
Animais , Minerais , Osso e Ossos/anatomia & histologia , Ovos/análise , Galinhas/classificação
20.
Br Poult Sci ; 54(6): 780-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24397514

RESUMO

1. This study evaluated the effects of diets with partial and total substitution of soya bean oil (SO) with flaxseed (linseed) oil (FO) on broiler chicken performance, carcass traits, meat chemical composition and blood serum metabolites. 2. A total of 448 one-d-old Cobb 500 broiler chicken were used. They were allotted among 4 treatments with 8 replications, using a completely randomised design, for 35 d. Four diets were compared: T1 = 100% SO (3%, 1-7 d; 4%, 8-21 d; and 5%, 22-35 d); T2 = 50% SO + 50% FO; T3 = 25% SO + 75% FO and T4 = 100% FO. 3. No significant differences were observed in body weight (BW), body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and blood serum metabolites (total triglycerides, TRI; total cholesterol, CHO; high-density lipoprotein, HDL; low-density lipoprotein, LDL; glucose, GLU; albumin, ALB; globulin, GLO; and total proteins, TPs). Significant effects were observed for TRI, CHO, HDL, GLU, HDL, LDL, ALB and GLO with regard to the day of collection. 4. Carcass traits did not show significant differences for the treatments. No significant differences were observed for breast and drumstick chemical compositions, with the exception of drumstick fat concentration (quadratic effect). 5. In conclusion, the partial or total substitution of SO with FO did not affect growth performance, carcass traits, meat chemical composition or blood serum profile in broiler chicken. Therefore, FO can be an alternative to SO in the diet formulation for broiler chicken.


Assuntos
Galinhas/fisiologia , Óleo de Semente do Linho/farmacologia , Carne/análise , Aumento de Peso/efeitos dos fármacos , Ração Animal/análise , Animais , Análise Química do Sangue/veterinária , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Relação Dose-Resposta a Droga , Óleo de Semente do Linho/administração & dosagem
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