Análise da elasticidade de transmissão de preços no mercado brasileiro de algodão [Analysis of price transmission elasticity in the Brazilian cotton market]

The article analyzes the elasticity of price transmission in the Brazilian cotton market from January, 1985, to December, 2000. For this purpose, the Dickey-Fuller Augmented (ADF) unit root test, the Johansen cointegration test, the Vector Error Correction model (VEC), and the exogenicity test are applied. The results show that the One Price Law does not apply to the Brazilian cotton market, because variations in cotton international prices are not fully transmitted to domestic prices in Brazil in the long run. The exogenicity test shows that domestic cotton prices in Brazil do not react to changes in the long run equilibrium relationship. Possibly, these results are directly associated with government intervention in the sector (1985 to 1988) as well as to the credit conditions available for cotton acquisition in the international market between 1990 and 1997.cotton, the one price law, cointegration, international trade, price transmission

Microstructure, mechanical properties and chemical degradation of brazed AISI 316 stainless steel/alumina systems

The main aims of the present study are simultaneously to relate the brazing parameters with: (i) the correspondent interfacial microstructure, (ii) the resultant mechanical properties and (iii) the electrochemical degradation behaviour of AISI 316 stainless steel/alumina brazed joints. Filler metals on such as Ag–26.5Cu–3Ti and Ag–34.5Cu–1.5Ti were used to produce the joints. Three different brazing temperatures (850, 900 and 950 °C), keeping a constant holding time of 20 min, were tested. The objective was to understand the influence of the brazing temperature on the final microstructure and properties of the joints. The mechanical properties of the metal/ceramic (M/C) joints were assessed from bond strength tests carried out using a shear solicitation loading scheme. The fracture surfaces were studied both morphologically and structurally using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction analysis (XRD). The degradation behaviour of the M/C joints was assessed by means of electrochemical techniques. It was found that using a Ag–26.5Cu–3Ti brazing alloy and a brazing temperature of 850 °C, produces the best results in terms of bond strength, 234 ± 18 MPa. The mechanical properties obtained could be explained on the basis of the different compounds identified on the fracture surfaces by XRD. On the other hand, the use of the Ag–34.5Cu–1.5Ti brazing alloy and a brazing temperature of 850 °C produces the best results in terms of corrosion rates (lower corrosion current density), 0.76 ± 0.21 μA cm−2. Nevertheless, the joints produced at 850 °C using a Ag–26.5Cu–3Ti brazing alloy present the best compromise between mechanical properties and degradation behaviour, 234 ± 18 MPa and 1.26 ± 0.58 μA cm−2, respectively. The role of Ti diffusion is fundamental in terms of the final value achieved for the M/C bond strength. On the contrary, the Ag and Cu distribution along the brazed interface seem to play the most relevant role in the metal/ceramic joints electrochemical performance

Biomechanics of Competitive Swimming Strokes

The aim of this chapter has two folds: (i): to perform a biomechanical characterization of the four competitive swimming strokes, based on the kinematics, kinetics and neuromuscular analysis; (ii) to report the relationships established between all the domains and how it might influence the swimming performance

NAP-2 Secreted by Human NK Cells Can Stimulate Mesenchymal Stem/Stromal Cell Recruitment

SummaryStrategies for improved homing of mesenchymal stem cells (MSCs) to a place of injury are being sought and it has been shown that natural killer (NK) cells can stimulate MSC recruitment. Here, we studied the chemokines behind this recruitment. Assays were performed with bone marrow human MSCs and NK cells freshly isolated from healthy donor buffy coats. Supernatants from MSC-NK cell co-cultures can induce MSC recruitment but not to the same extent as when NK cells are present. Antibody arrays and ELISA assays confirmed that NK cells secrete RANTES (CCL5) and revealed that human NK cells secrete NAP-2 (CXCL7), a chemokine that can induce MSC migration. Inhibition with specific antagonists of CXCR2, a receptor that recognizes NAP-2, abolished NK cell-mediated MSC recruitment. This capacity of NK cells to produce chemokines that stimulate MSC recruitment points toward a role for this immune cell population in regulating tissue repair/regeneration

Favourable areas for co-occurrence of parapatric species: niche conservatism and niche divergence in Iberian tree frogs and midwife toads

Aim Predicting species responses to global change is one of the most pressing issues in conservation biogeography. A key part of the problem is understanding how organisms have reacted to climatic changes in the past. Here we use species distribution modelling to infer the effects of climate changes since the Last Interglacial (LIG, about 130,000 ybp) on patterns of genetic structure and diversity in the Western Spadefoot toad (Pelobates cultripes) in combination with spatially-explicit phylogeographic analyses. Location Iberian Peninsula and mainland France. Methods 524 individuals from 54 populations across the species range were sampled to document patterns of genetic diversity and infer their evolutionary history based on data from mtDNA and fourteen polymorphic microsatellites. Generalized linear models based on distribution data were used to infer climatic favourability for the species in the present and in paleoclimatic simulations for the LIG, the Mid Holocene and the last glacial maximum (LGM). Results Estimates of genetic diversity show a decreasing trend from south to north, suggesting persistence of high historical population sizes in the southern Iberian Peninsula. Species distribution models show differences in climatic favourability through time, with significant correlations between historically stable favourable areas and current patterns of genetic diversity. These results are corroborated by Bayesian Skyline Plots and continuous diffusion phylogeographic analyses. Main conclusions The results indicate the presence of southern refugia, with moderate recent expansions at the northern end of the species’ range. Toads at the northern range margin exhibit the lowest genetic diversity and occupy areas of high past climate variability, classified as marginal in terms of favourability, rendering these populations most vulnerable to climate-mediated changes in the long term

Relação entre precocidade de maturação e desidratação das sementes de pêssego

An experiment was performed at the Instituto Agronômico de Campinas, SP, Brazil, to determine the relation between fruit precociusness and degree of seed dehydration of 18 peach cultivar (Prunus persica (L.) Batsch) after exposure at room temperature for 96 hours. Results showed that the earlier the ripening period, the more drastic is seed dehydration. Loss of seed weight ranged from 89.6 to 46.4% for the earliest and latest muturing cultivar, respectively. The important implications of these findings to the peach breeding program are the following: a) peach cultivars could be adequately classified as to maturation period and, b) an appropriate method of seed germination could be established for each cultivar.Conduziu-se um experimento, no Instituto Agronômico de Campinas, SP, para averiguar a relação entre a precocidade de maturação de 18 cultivares de pêssego (Prunus persica (L.) Batsch) e o grau de desidratação das sementes, expostas às condições de ambientes fechado, por 96 horas. Os resultados mostraram que, quanto mais precoce a cultivar, mais drástica é a desidratação. A amplitude da desidratação foi de 89,6% na cultivar mais precoce, e 46.4% na mais tardia. Estes dados constituem valioso elemento para os trabalhos de melhoramento genético, pois: a) permitem classificar as cultivares com boa precisão quanto à respectiva faixa de maturação dos frutos; b) possibilitam estabelecer, para cada cultivar, um método adequado de germinação

Phenotypic and proliferative modulation of human mesenchymal stem cells via crosstalk with endothelial cells

AbstractThe purpose of this work was to investigate if a coculture system of human mesenchymal stem cells (hMSC) with endothelial cells (human umbilical vein endothelial cells, HUVEC) could modulate the phenotype and proliferation of harvested MSCs. In addition to previous investigations on the crosstalk between these two cell types, in the present work different relative cell ratios were analyzed for long, therapeutically relevant, culture periods. Moreover, MSCs osteogenic commitment was assessed in a non-osteogenic medium and in the presence of HUVECs through magnetic cell separation, cell quantification by flow cytometry, morphology by fluorescent microscopy, metabolic activity and gene expression of osteogenic markers. Collectively, the present findings demonstrate that, by coculturing MSCs with HUVECs, there was not only the promotion of osteogenic differentiation (and its enhancement, depending on the relative cell ratios used), but also a significant increase on MSCs proliferation. This augmentation in cell proliferation occurred independently of relative cell ratios, but was favored by higher relative amounts of HUVECs. Taken together, this data suggests that HUVECs not only modulate MSC phenotype but also their proliferation rate. Therefore, a coculture system of MSCs and HUVECs can a have a broad impact on bone tissue engineering approaches

Structural and dielectric properties of laser ablated BaTiO3 films deposited over electrophoretically dispersed CoFe2O4 grains

Thin film nanocomposites with mixed connectivity, composed by CoFe2O4 grains deposited by electrophoresis on Si|Pt substrates and subsequently covered by a laser ablation deposited BaTiO3 layer were prepared with different cobalt ferrite concentrations. Their structure presented a combination of BaTiO3, with its tetragonal and the orthorhombic phases coexisting at room temperature, and CoFe2O4 with the cubic spinel structure. The cobalt ferrite nanograins were under in-plane tensile stress, while the BaTiO3 phase was under in-plane compressive stress. The dielectric measurements showed that as the barium titanate grain size decreased, its ferroelectric Curie temperature shifted to lower temperatures relative to the bulk. This grain size dependent TC shift was associated and modeled by a core-shell structure of BaTiO3 grains in the films, with a tetragonal core and cubic shell. Additionally a diffuse tetragonal-orthorhombic phase transition was observed and, in agreement with Raman spectroscopy results, associated to the coexistence of barium titanate orthorhombic and tetragonal phases in the room temperature region. This led to the formation of polar nanoclusters with random polarization orientations, which induced a frustrated phase transition between the tetragonal and orthorhombic phases of barium titanate in the films.This work has been supported by Fundacao para a Ciencia e Tecnologia (FCT) and FEDER, through the projects PTDC/CTM/099415/2008 and PTDC/CTM-NAN/115125/2009 and by QREN-ON2-O Novo Norte, through the project Operacao Norte-070124-FEDER-000070. J. G. Barbosa and I. T. Gomes gratefully acknowledge PhD grants from Fundacao para a Ciencia e Tecnologia (SFRH/BD/41913/2007 and SFRH/BD/36348/2007, respectively)

13th FINA WORLD CHAMPIONSHIP FINALS: STROKE KINEMATICS AND RACE TIMES ACCORDING TO PERFORMANCE, GENDER AND EVENT

The aim of this work was to compare the stroke kinematics and race times of the freestyle final races at the 13th FINA World Championships between: (i) the three medalists versus the last three finalists; (ii) males versus female swimmers; (iii) all events in each gender. Data was collected from the champioships official web site. There were no significant differences in the stroke kinematics neither in the race times between medallists and non-medallists. There were significant effects in the stroke kinematics and race times according to race event. There were significant effects in the stroke kinematics and race times according to swimmers gender. It seems there are different tactics and biomechanical strategies according to gender and swimming event

Efeito do tipo de parto na colonização oral e cárie dentária nas crianças: revisão sistemática da literatura

ABSTRACT - This review investigated whether mode of delivery influences the colonization of infant’s oral cavity and the risk of early childhood caries (ECC). The search strategy included systematic searching of electronic databases (Web of Science and PubMed) for articles published (1995–2015) and hand searching of references lists. Outcomes of interest were the presence of oral caries-related microorganisms, oral species considered protective against caries, and dental caries. Other outcomes included severity of dental caries, dental claims, and age at first dental visit. Study quality was assessed using the EPHPP tool. For each study, we present odds ratios and respective 95% confidence intervals for the association between these outcomes and the mode of delivery. Fourteen studies were identified. In 5 out of 8 studies addressing oral colonization, children born by cesarean section were less likely to harbor caries-related microorganisms as well as protective bacteria against caries and acquired caries-related microorganisms earlier, when compared with vaginally delivered children. No consistent results were obtained for the association between mode of delivery and dental caries. Although there were differences in oral colonization by mode of delivery, it seems that other determinants rather than mode of delivery could be major contributors to the development of ECC.RESUMO - Esta revisão investigou se o tipo de parto influencia a colonização da cavidade oral do bebé e o risco de cárie precoce na infância (CPI). A estratégia de pesquisa incluiu a pesquisa sistemática em bases de dados eletrónicas (Web of Science e PubMed) para artigos publicados (1995–2015) e a pesquisa manual de listas de referências. Os principais resultados apontaram para a presença de microrganismos relacionados com a cárie oral, espécies orais consideradas protetoras contra a cárie e a cárie dentária. Outros resultados obtidos incluíram a gravidade da cárie dentária, as reclamações odontológicas e a idade na primeira consulta odontológica. A qualidade do estudo foi avaliada usando a ferramenta EPHPP. Para cada estudo apresentamos odds-ratio (OR) e respetivos intervalos de confiança de 95% (IC 95%) para a associação entre esses desfechos e o tipo de parto. Foram identificados catorze estudos. Em cinco de oito estudos abordando a colonização oral, as crianças nascidas por cesariana foram menos propensas a abrigar microrganismos relacionados com a cárie, bem como bactérias protetoras contra a cárie e micro-organismos relacionados com cárie adquirida anteriormente, quando comparadas com crianças nascidas de parto vaginal. Não foram obtidos resultados consistentes para a associação entre o tipo de parto e a cárie dentária. Embora houvesse diferenças na colonização oral por tipo de parto, parece que outros determinantes, em vez do tipo de parto, podem ser os principais fatores que contribuem para o desenvolvimento da CPI.info:eu-repo/semantics/publishedVersio