Antiferromagnetic and ferromagnetic spintronics and the role of in-chain and inter-chain interaction on spin transport in the Heisenberg ferromagnet.

Spin-transport and current-induced torques in ferromagnet heterostructures given by a ferromagnetic domain wall are investigated. Furthermore, the continuum spin conductivity is studied in a frustrated spin system given by the Heisenberg model with ferromagnetic in-chain interaction [Formula: see text] between nearest neighbors and antiferromagnetic next-nearest-neighbor in-chain interaction [Formula: see text] with aim to investigate the effect of the phase diagram of the critical ion single anisotropy [Formula: see text] as a function of [Formula: see text] on conductivity. We consider the model with the moderate strength of the frustrating parameter such that in-chain spin-spin correlations that are predominantly ferromagnetic. In addition, we consider two inter-chain couplings [Formula: see text] and [Formula: see text], corresponding to the two axes perpendicular to chain where ferromagnetic as well as antiferromagnetic interactions are taken into account.

Human health risk assessment associated with the consumption of mussels (Perna perna) and oysters (Crassostrea rhizophorae) contaminated with metals and arsenic in the estuarine channel of Vitória Bay (ES), Southeast Brazil.

The estuarine channel of Vitória Bay was evaluated regarding bioaccumulation of metals (Al, Ba, Mn, Fe, Zn, Cu, Cr, Pb, Ni, Cd, Hg) and As in mollusks. Mussels from an aquaculture farm and transplanted into the estuary, whereas oysters were collected in situ in the same area. Concentrations of Al, Mn, Fe, Cr and As were higher in P. perna, whereas C. rhizophorae bioaccumulated more Ba, Zn and Cu. Arsenic concentrations in P. perna exceeded the limit of the Brazilian legislation in the outer estuary. Salinity seemed to influence metal uptake differently for each bivalve, with P. perna absorbing more metal at higher salinities and C. rhizophorae in areas of lower salinity. Hazard index (HI) >1 revealed risk for both bivalves for high level consumers. Target Cancer Risk (TCR) for As revealed threat for human health associated with the consumption of mussels and oysters from the study area.

Self-organizing three-dimensional Ising model of financial markets.

The three-dimensional Ising model in an external field is used as a mathematical model for price dynamics of financials market. The model allows us to test within the same framework the comparative explanatory power of rational agents versus irrational agents with respect to the stylized facts of the financial markets. We obtain the price dynamics in terms of the strength of the field that reinforces the sensitivity of the agent's sentiment to external news. The exponent of long-tail cumulative probability density is determined and satisfies the inverse of the cubic law. Furthermore, the long range memory of the model is studied using different methods to determine the Hurst index of the model. The results obtained display that the model does serve as a mathematical model for financial markets.

Influence of Nitric Oxide-Cyclic GMP and Oxidative STRESS on Amyloid-ß Peptide Induced Decrease of Na,K-ATPase Activity in Rat Hippocampal Slices.

Amyloid-ß peptide (Aß) has been shown to cause synaptic dysfunction and can render neurons vulnerable to excitotoxicity and oxidative stress. Na,K-ATPase plays an important role to maintain cell ionic equilibrium and it can be modulated by N-methyl-D-aspartate (NMDA)-nitric oxide (NO)-cyclic GMP pathway. Disruption of NO synthase (NOS) activity and reactive oxygen species (ROS) production could lead to changes in Na,K-ATPase isoforms' activities that may be detrimental to the cells. Our aim was to evaluate the signaling pathways of Aß in relation to NMDA-NOS-cyclic GMP versus oxidative stress on α1-/α2,3-Na,K-ATPase activities in rat hippocampal slices. Aß1-40 induced a concentration-dependent increase of NOS activity and increased cyclic guanosine monophosphate (cGMP), TBARS (thiobarbituric acid reactive substances), and 3-Nitrotyrosine (3-NT)-modified protein levels in rat hippocampal slices. The increase in NOS activity and cyclic GMP levels induced by Aß1-40 was completely blocked by MK-801 (inhibitor of NMDA receptor) and L-NAME (inhibitor of NOS) pre-treatment but changes in TBARS levels were only partially blocked by both compounds. The Aß treatment also decreased Na,K-ATPase activity which was reverted by N-nitro-L-arginine methyl ester hydrochloride (L-NAME) but not by MK-801 pre-treatment. The decrease in enzyme activity induced by Aß was isoform-specific since only α1-Na,K-ATPase was affected. These findings suggest that the activation of NMDA-NOS signaling cascade linked to α2,3-Na,K-ATPase activity may mediate an adaptive, neuroprotective response to Aß in rat hippocampus.

Evaluation of bioavailability of trace metals through bioindicators in a urbanized estuarine system in southeast Brazil.

The mussel Perna perna is one of the most used bioindicators of coastal areas and the most economically exploited species in Brazil through mariculture. In the present study, P. perna was used to investigate metal pollution in the estuarine area of Vitória Bay. Four sampling sites were located along an estuarine branch of Vitória Bay and stations were sampled during three campaigns. Trace metals in the tissues of P. perna were evaluated as well as dissolved trace metals and other ancillary variables in the water column. Dissolved Cd, Pb, Cu, Ni, and Fe concentrations surpassed the tolerance limits stablished by legislation in all the sampling campaigns. P. perna exhibited concentrations in disagreement with the Brazilian legislation for Cr and As. A general trend of higher concentrations in outer stations was observed for most metals, what suggested the occurrence of flocculation process in the lower estuary, reducing the concentrations of dissolved elements and increasing their bioavailability for the biota through the particulate form. Cd was highlighted with elevated concentrations in dissolved fraction but not detected in P. perna, probably due to chlor-complex formation under influence of more saline waters. Al, Ba, Mn, Fe, Cu, Zn, Ni, Cr, Pb, and As were considered bioavailable, once they were accumulated in the mussels' tissues. Hazard index (HI) and target cancer risk (TCR) showed that the consumption of mussels from the study area offers health risk issues, being iron and arsenic the main contributors for the high indexes.

Code of Ethics and Conduct of the Brazilian Association of Embryologists - PRONÚCLEO.

For more than three decades, Brazilian Clinical Embryologists have been working without specific regulations and following the standards adopted by other healthcare professionals. This document aims to guide behavior and decision-making, while providing directions to embryologist with the purpose of aiding professionals involved with assisted reproduction procedures and their patients. The Code of Ethics and Conduct is an important breakthrough and the first step toward regulating Clinical Embryology as a profession.

Detecting genomic damages in the frog Dendropsophus minutus: preserved versus perturbed areas.

The aim of the study was to use the comet assay (single-cell gel electrophoresis) and micronucleus test to assess the extent of genomic damage in the whole blood of Dendropsophus minutus from agroecosystems with great use of agrochemicals and to compare the results to those obtained from animals living in unpolluted areas. Our results indicated that specimens of D. minutus collected in perturbed areas exhibited higher amounts of DNA damage in blood cells in comparison to animals from areas free of agricultural activities. The average and standard deviation of all comet assay parameters (tail length, percentage of DNA in the tail, and olive tail moment) and micronuclei frequency were significantly higher in specimens collected in perturbed areas than in the animals from preserved areas. Our study showed that animals from perturbed areas, such as agroecosystems, tend to have higher amounts of DNA damage than animals from reference areas. Moreover, we can conclude that D. minutus tadpoles could be included as a model organism in biomonitoring studies.

Citrus pulp as a dietary source of antioxidants for lactating holstein cows fed highly polyunsaturated Fatty Acid diets.

The effects of feeding pelleted citrus pulp (PCP) as a natural antioxidant source on the performance and milk quality of dairy cows fed highly polyunsaturated fatty acid (FA) diets were evaluated. Four lactating Holstein cows were assigned to a 4×4 Latin-square. Treatments, on a dry matter (DM) basis, were i) control diet; ii) 3% soybean oil; iii) 3% soybean oil and 9% PCP and; iv) 3% soybean oil and 18% PCP. When cows fed on citrus pulp, the DM intake tended to decrease. The total tract apparent digestibility of DM and ether extract decreased when cows fed on the control diet compared to other diets. Cows fed PCP had higher polyphenols and flavonoids content and higher total ferric reducing antioxidant power (FRAP) in milk compared to those fed no pelleted citrus pulp. Cows fed 18% PCP showed higher monounsaturated FA and lower saturated FA in milk fat compared with cows fed the other diets. The lowest n-6 FA proportion was in milk fat from cows fed control. The present study suggests that pelleted citrus pulp added to 9% to 18% DM increases total polyphenols and flavonoids concentration, and the FRAP in milk.

Effect of inactive dry yeast from sugar cane as protein source on rumen fermentation in Saanen goats / Efeito da levedura seca inativa da cana-de-açúcar como fonte de proteína sobre a fermentação ruminal de caprinos Saanen

Five castrated and ruminally cannulated Saanen goats (±48.19kg) were used to evaluate intake, digestibility and rumen fermentation parameters of diets with inactive dry yeast as a soybean meal substitute (0, 25, 50, 75 and 100 percent). Goats were randomly assigned to a 5×5 (five levels of dry yeast x five periods) Latin square design. Diets were composed of corn silage (40 percent), ground corn, soybean meal and/or dry yeast and mineral supplement. The intake and digestibility of DM, OM, CP, NDF and TC were not influenced by the treatments. However, EE intake showed negative linear effect. The TDN content did not change with the inclusion of dry yeast in the diets. The pH, N-NH3 concentration and rumen short-chain fatty acids content did not differ among diets. Rumen content scanning electron microscopy observations did not suggest microbial colonization and degradation changes. Dry yeast from sugar cane can replace soybean meal in diets for Saanen goats without changing the rumen fermentation pattern, intake and digestibility.

Com o objetivo de avaliar a ingestão, a digestibilidade e os parâmetros de fermentação ruminal de rações com de levedura seca em substituição ao farelo de soja (0; 25; 50; 75 e 100 por cento), foram utilizados cinco caprinos Saanen (± 48,19kg) castrados e canulados no rúmen distribuídos em quadrado latino 5 x 5 (cinco níveis x cinco períodos). As rações foram compostas de silagem de milho (40 por cento), milho moído, farelo de soja e/ou levedura seca e suplemento vitamínico-mineral. A ingestão e a digestibilidade da MS, MO, PB, FDN e dos CT não foram alteradas. A ingestão de EE apresentou efeito linear negativo. O NDT não foi alterado com a inclusão da levedura seca. O pH e as concentrações de N-NH3 e de ácidos graxos de cadeia curta no rúmen não apresentaram alterações. As observações por microscopia eletrônica de varredura não indicaram mudanças na colonização microbiana e na degradação da digesta ruminal. A levedura seca da cana-de-açúcar não altera o padrão de fermentação ruminal, a ingestão e a digestibilidade, podendo substituir o farelo de soja em rações de caprinos Saanen.

Influence of N-methyl-D-aspartate receptors on ouabain activation of nuclear factor-κB in the rat hippocampus.

It has been shown that ouabain (OUA) can activate the Na,K-ATPase complex and mediate intracellular signaling in the central nervous system (CNS). Inflammatory stimulus increases glutamatergic transmission, especially at N-methyl-D-aspartate (NMDA) receptors, which are usually coupled to the activation of nitric oxide synthase (NOS). Nuclear factor-κB (NF-κB) activation modulates the expression of genes involved in development, plasticity, and inflammation. The present work investigated the effects of OUA on NF-κB binding activity in rat hippocampus and the influence of this OUA-Na,K-ATPase signaling cascade in NMDA-mediated NF-κB activation. The findings presented here are the first report indicating that intrahippocampal administration of OUA, in a concentration that did not alter Na,K-ATPase or NOS activity, induced an activation of NF-κB, leading to increases in brain-derived neurotrophic factor (Bdnf), inducible NOS (iNos), tumor necrosis factor-α (Tnf-α), and B-cell leukemia/lymphoma 2 (Bcl2) mRNA levels. This response was not linked to any significant signs of neurodegeneration as showed via Fluoro-Jade B and Nissl stain. Intrahippocampal administration of NMDA induced NF-κB activation and increased NOS and α(2/3) -Na,K-ATPase activities. NMDA treatment further increased OUA-induced NF-κB activation, which was partially blocked by MK-801, an antagonist of NMDA receptor. These results suggest that OUA-induced NF-κB activation is at least in part dependent on Na,K-ATPase modulatory action of NMDA receptor in hippocampus. The interaction of these signaling pathways could be associated with biological mechanisms that may underlie the basal homeostatic state linked to the inflammatory signaling cascade in the brain.

Avaliação da carcaça de cabritos Saanen alimentados com dietas com grãos de oleaginosas / Carcass evaluation of Saanen kids fed oilseeds diets

Foram utilizados 16 cabritos Saanen não castrados dos 15,16±1,60kg até 30,61±0,33kg de peso vivo, distribuídos em delineamento inteiramente ao acaso, alimentados com dietas (tratamentos) com grãos de linhaça, girassol ou canola. A dieta-controle foi formulada com feno de aveia, farelo de soja, milho moído e suplemento vitamínico-mineral. Os pesos da carcaça quente e fria e os rendimentos da carcaça e de cortes comerciais não foram modificados pelos tratamentos. A dieta com grãos de canola resultou em maior perda por resfriamento da carcaça e menor proporção de gordura no lombo, e a proporção de osso no lombo foi maior para os animais que receberam linhaça ou canola. Os teores de umidade, proteína, lipídios totais e cinzas do músculo Longissimus dorsi não foram alterados com a adição dos grãos de oleaginosas. A dieta com grãos de linhaça resultou em aumento do teor de ômega-3 no músculo, e o teor de colesterol e a razão ômega-6/ômega-3 foram menores nos tratamentos que continham linhaça, girassol e canola. A inclusão dos grãos de oleaginosas nas dietas não alterou as características quantitativas da carcaça de cabritos Saanen, mas melhorou a qualidade da carne, que apresentou menos colesterol e mais ômega-3, com o uso de linhaça.

Sixteen non-castrated Saanen kids from 15.16±1.60kg to 30.61±0.33kg of body weight, allotted into completely randomized experimental design, were fed experimental diets (treatments) containing flaxseed, sunflower, or canola oilseeds, and a control diet based on oat hay, soybean meal, ground corn, and vitamin-mineral supplement. Hot and cold carcass weight, carcass and commercial cuts yields were not modified by treatments. Canola seed in diets resulted in greater weight loss by cooling and lower loin fat proportion. Loin bone proportion was higher for kids fed flaxseed or canola. The moisture, protein, lipid, and ash contents in the Longissimus dorsi were not affected by oilseeds inclusion. Flaxseed in the diet increased the omega-3 content in muscle. Cholesterol content and omega-6/omega-3 ratio were lower to the treatments with flaxseed, sunflower, and canola. Oilseeds in diets of Saanen kids did not alter the carcass quantitative traits, but improved the quality of meat, with less cholesterol and more omega-3 using flaxseed.

Single nucleotide polymorphisms from Theobroma cacao expressed sequence tags associated with witches' broom disease in cacao.

In order to increase the efficiency of cacao tree resistance to witches' broom disease, which is caused by Moniliophthora perniciosa (Tricholomataceae), we looked for molecular markers that could help in the selection of resistant cacao genotypes. Among the different markers useful for developing marker-assisted selection, single nucleotide polymorphisms (SNPs) constitute the most common type of sequence difference between alleles and can be easily detected by in silico analysis from expressed sequence tag libraries. We report the first detection and analysis of SNPs from cacao-M. perniciosa interaction expressed sequence tags, using bioinformatics. Selection based on analysis of these SNPs should be useful for developing cacao varieties resistant to this devastating disease.

Low-temperature spin transport in a S = 1 one-dimensional antiferromagnet.

We study spin transport in the insulating antiferromagnet with S = 1 in one dimension. The spin conductivity is calculated, at zero temperature, using a modified spin wave theory and the Kubo formalism, within the ladder approximation. Two-magnon processes provide the dominant contribution to the spin conductivity. At finite temperature, free magnons are activated, and turn the system into a perfect spin conductor, i.e., the spin conductivity has a Drude form with infinite scattering time.

Amyloid beta-peptide activates nuclear factor-kappaB through an N-methyl-D-aspartate signaling pathway in cultured cerebellar cells.

Amyloid beta-peptide (A beta) likely causes functional alterations in neurons well prior to their death. Nuclear factor-kappaB (NF-kappaB), a transcription factor that is known to play important roles in cell survival and apoptosis, has been shown to be modulated by A beta in neurons and glia, but the mechanism is unknown. Because A beta has also been shown to enhance activation of N-methyl-D-aspartate (NMDA) receptors, we investigated the role of NMDA receptor-mediated intracellular signaling pathways in A beta-induced NF-kappaB activation in primary cultured rat cerebellar cells. Cells were treated with different concentrations of A beta1-40 (1 or 2 microM) for different periods (6, 12, or 24 hr). MK-801 (NMDA antagonist), manumycin A and FTase inhibitor 1 (farnesyltransferase inhibitors), PP1 (Src-family tyrosine kinase inhibitor), PD98059 [mitogen-activated protein kinase (MAPK) inhibitor], and LY294002 [phosphatidylinositol 3-kinase (PI3-k) inhibitor] were added 20 min before A beta treatment of the cells. A beta induced a time- and concentration-dependent activation of NF-kappaB (1 microM, 12 hr); both p50/p65 and p50/p50 NF-kappaB dimers were involved. This activation was abolished by MK-801 and attenuated by manumycin A, FTase inhibitor 1, PP1, PD98059, and LY294002. A beta at 1 microM increased the expression of inhibitory protein I kappaB, brain-derived neurotrophic factor, inducible nitric oxide synthase, tumor necrosis factor-alpha, and interleukin-1 beta as shown by RT-PCR assays. Collectively, these findings suggest that A beta activates NF-kappaB by an NMDA-Src-Ras-like protein through MAPK and PI3-k pathways in cultured cerebellar cells. This pathway may mediate an adaptive, neuroprotective response to A beta.

[Clinical response to inhalation and oral antibiotics in patients with bronchiectasis]. / Avaliação da resposta clínica ao uso de antibióticos por via oral e via inalatória em pacientes portadores de bronquiectasias.

INTRODUCTION: The aim of this technique was to achieve high concentration of the antibiotic that excedeed the minimal inhibitory concentration (MIC) of the microbial load present in the sputum. METHOD: To evaluate the bronchiectasis patients with pictures of infectious exacerbations response to the treatment with antibiotic by oral way (roxitromicin 300 mg/day for 21 days) and in cases of failure of this schema the use of antibiotic by inhalatory way (gentamicin 80 mg/2 times day for 21 days), 28 patients were evaluated a special ambulatory, some signs and respiratory symptoms according to the "Cotes modified scale" (sputum, cough, bronchospasm and dyspnea). STATISTICAL ANALYSIS: We used: Kappa concordant test and McNemar test for discordation in the evaluation of the degree of signal and respiratory symptoms, Wilcoxon test for periods without infection, Fisher test for the collaterals effects presented, G of Cochran test for the personal history analysis. RESULTS: The personal history did not influence the evolution of bronchopulmonary infeccion, the evaluated signs and symptoms had significant improvement except dyspnea that stayed the same in 80% of the cases. DISCUSSION: The group that had used the antibiotics schema by inhalatory way after oral scheme failure had a significant longer period without bronchopulmonary infection but with superior collateral effects without clinicals repercussions. CONCLUSION: The use of inhalatory antibiotic in infectious exacerbations in patients with bronchiectasis was better than the oral way.

Avaliaçäo da resposta clínica ao uso de antibióticos por via oral e via inalatória em pacientes portadores de bronquiectasias / Evaluation of clinical response in the antibiotics use by inhalatory and oral ways in patients with bronchiectasis

Objetivo. A base desta técnica foi obter alta concentração do antibiótico que excedia a concentração mínima inibitória (MIC) para a carga bacteriana presente no escarro. Método. Para avaliar a resposta de pacientes portadores de bronquiectasis em quadros de exacerbações infecciosas ao tratamento com antibiótico por via oral (roxitromicina 300 mg/dia por 21 dias) e nos casos de fracasso deste esquema uso de antibiótico por via inalatória (gentamicina 80 mg/2 vezes dia por 21 dias), foram avaliados em 28 pacientes atendidos noambulatório da especialidade, alguns sinais e sintomas respiratórios de acordo com a escala de Cotes modificada (secreção brônquica, tosse, broncoespasmo e dispnéia). Análise Estatística. Utilizamos o seguinte tratamento estatístico: teste de concordância Kappa e teste de McNemar para a discordância na avaliação dos graus de sinais e sintomas respiratórios, teste exato de Fischer para os efeitos colaterais apresentados, teste G de Cochran para análise dos antecedentes pessoais. Resultados. Observamos que a presença dos antecedentes pessoais não influenciaram a evolução da infecção brocopulmonar, houve melhora significante nos sinais e sintomas avaliados excetuando-se a dispnéia que permaneceu inalterada em 80 por cento dos casos. Discussão. O grupo que fez de esquema antibiótico por via inalatória após fracasso do esquema via oral foi beneficiado com período médio sem infecção brocopulmonar significantemente superior, embora a presença de efeitos colaterais tenha sido superior neste grupo, porém sem repercussão clínica. Conclusão. O controle de quadros de exacerbação infecciosa em portadores de bronquiectasias foi melhor com o antibiótico por via inalatória do que por via oral.

Cranio-orbital approach for the paraclinoidal and anterior communicating aneurysms.

Aneurysms arising at the proximal intracranial carotid artery (between cavernous sinus and posterior communicating artery) and at the anterior communicating complex may present with technical difficulties regarding appropriate access without excessive brain retraction. In a series of 15 patients the authors show the use of the cranio-orbital approach, formerly designed in the access of skull base tumors, for these subgroups of aneurysms. They discuss the advantages of a basal avenue in minimizing brain retraction, better anatomical orientation, obviation of tissue ressection and easier extra-dural bone removal. It was not identified any complication due to the described approach.