Indústria de máquinas agrícolas no Brasil: um modelo para estimação da demanda de tratores para o triênio 2016 – 2018

O objetivo desta dissertação foi estimar a demanda de tratores agrícolas para o mercado brasileiro no triênio 2016-2018, utilizando-se para isto de técnicas de econometria de séries temporais, neste caso, modelos univariados da classe ARIMA e SARIMA e ou multivariados SARIMAX. Justifica-se esta pesquisa quando se observa a indústria de máquinas agrícolas no Brasil, dados os ciclos econômicos e outros fatores exógenos aos fundamentos econômicos da demanda, onde esta enfrenta muitos desafios. Dentre estes, a estimação de demanda se destaca, pois exerce forte impacto, por exemplo, no planejamento e custo de produção de curto e médio prazo, níveis de inventários, na relação com fornecedores de materiais e de mão de obra local, e por consequência na geração de valor para o acionista. Durante a fase de revisão bibliográfica foram encontrados vários trabalhos científicos que abordam o agronegócio e suas diversas áreas de atuação, porém, não foram encontrados trabalhos científicos publicados no Brasil que abordassem a previsão da demanda de tratores agrícolas no Brasil, o que serviu de motivação para agregar conhecimento à academia e valor ao mercado através deste. Concluiu-se, após testes realizados com diversos modelos que estão dispostos no texto e apêndices, que o modelo univariado SARIMA (15,1,1) (1,1,1) cumpriu as premissas estabelecidas nos objetivos específicos para escolha do modelo que melhor se ajusta aos dados, e foi escolhido então, como o modelo para estimação da demanda de tratores agrícolas no Brasil. Os resultados desta pesquisa apontam para uma demanda de tratores agrícolas no Brasil oscilando entre 46.000 e 49.000 unidades ano entre os anos de 2016 e 2018.

Speculative bubbles and contagion: analysis of volatility's clusters during the DotCom bubble based on the dynamic conditional correlation model

Reviewing the de nition and measurement of speculative bubbles in context of contagion, this paper analyses the DotCom bubble in American and European equity markets using the dynamic conditional correlation (DCC) model proposed by (Engle and Sheppard 2001) as on one hand as an econometrics explanation and on the other hand the behavioral nance as an psychological explanation. Contagion is de ned in this context as the statistical break in the computed DCCs as measured by the shifts in their means and medians. Even it is astonishing, that the contagion is lower during price bubbles, the main nding indicates the presence of contagion in the di¤erent indices among those two continents and proves the presence of structural changes during nancial crisis

Estimativa do balanço térmico por radiação em vacas Holandesas expostas ao sol e à sombra em ambiente tropical

É apresentado um método para a estimativa do balanço térmico por radiação em vacas da raça Holandesa expostas ao sol e sob a sombra em uma pastagem, com o objetivo de estabelecer um padrão morfológico mais adequado para esses animais em região tropical. O método envolve a determinação das características do pelame (área de superfície de malhas negras, espessura da capa, comprimento e diâmetro dos pêlos, número de pêlos por unidade de área), temperatura da superfície da capa e da epiderme e variáveis ambientais (irradiância solar, temperatura do ar e de globo, vento). Foi determinada a quantidade de radiação de ondas curtas efetivamente transmitida através do pelame e que atinge as camadas profundas da epiderme. Demonstrou-se, por intermédio de um exemplo prático, que as áreas de pelame negro apresentaram balanço radiante mais elevado que as áreas brancas, mas estas últimas possuiam maior transmissividade para a radiação de ondas curtas. Animais predominantemente negros foram melhor protegidos contra a radiação de ondas curtas que os predominantemente brancos, especialmente quando a capa de pelame é pouco espessa (até 4 a 7 mm), mais adequada para ambientes tropicais.

Independent clonal origin of multiple uterine leiomyomas that was determined by X chromosome inactivation and microsatellite analysis

Objective: In an attempt to clarify the clonality and genetic relationships that are involved in the tumorigenesis of uterine leiomyomas, we used a total of 43 multiple leiomyomas from 14 patients and analyzed the allelic status with 15 microsatellite markers and X chromosome inactivation analysis.Study design: We have used a set of 15 microsatellite polymorphism markers mapped on 3q, 7p, 11, and 15q by automated analysis. The X chromosome inactivation was evaluated by the methylation status of the X-linked androgen receptor gene.Results: Loss of heterozygosity analysis showed a different pattern in 7 of the 8 cases with allelic loss for at least 1 of 15 microsatellite markers that were analyzed. A similar loss of heterozygosity findings at 7p22-15 was detected in 3 samples from the same patient. X chromosome inactivation analysis demonstrated the same inactivated allele in all tumors of the 9 of 12 informative patients;. different inactivation patterns were observed in 3 cases.Conclusion: Our data support the concept that uterine leiomyomas are derived from a single cell but are generated independently in the uterus. Loss of heterozygosity findings at 7p22-15 are consistent with previous data that suggested the relevance of chromosomal aberrations at 7p that were involved in individual uterine leiomyomas. (C) 2005 Mosby, Inc. All rights reserved.

Follicular deviation and acquisition of ovulatory capacity in bovine follicles

Selection of dominant follicles in cattle is associated with a deviation in growth rate between the dominant and largest subordinate follicle of a wave (diameter deviation). To determine whether acquisition of ovulatory capacity is temporally associated with diameter deviation, cows were challenged with purified LH at known times after a GnRH-induced LH surge (experiment 1) or at known follicular diameters (experiments 2 and 3). A 4-mg dose of LH induced ovulation in all cows when the largest follicle was greater than or equal to 12 mm (16 of 16), in 17% (1 of 6) when it was 11 mm, and no ovulation when it was less than or equal to 10 mm (0 of 19). To determine the effect of LH dose on ovulatory capacity, follicular dynamics were monitored every 12 h, and cows received either 4 or 24 mg of LH when the largest follicle first achieved 10 mm in diameter (experiment 2). The proportion of cows ovulating was greater (P < 0.05) for the 24-mg (9 of 13; 69.2%) compared with the 4-mg (1 of 13; 7.7%) LH dose. To determine the effect of a higher LH dose on follicles near diameter deviation, follicular dynamics were monitored every 8 h, and cows received 40 mg of LH when the largest follicle first achieved 7.0, 8.5, or 10.0 mm (experiment 3). No cows with a follicle of 7 mm (0 of 9) or 8.5 mm (0 of 9) ovulated, compared with 80% (8 of 10) of cows with 10-mm follicles. Thus, follicles acquired ovulatory capacity at about 10 mm, corresponding to about 1 day after the start of follicular deviation, but they required a greater LH dose to induce ovulation compared with larger follicles. We speculate that acquisition of ovulatory capacity may involve an increased expression of LH receptors on granulosa cells of the dominant follicle and that this change may also be important for further growth of the dominant follicle.

AT(1) receptor blockade in the lateral parabrachial nucleus reduces the effects of muscimol on sodium intake

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A NEW HOST RECORD, PALAEMONETES CARTERI (GORDON, 1935) (DECAPODA, PALAEMONIDAE), FOR TELOTHA HENSELII (VON MARTENS, 1869) (ISOPODA, CYMOTHOIDAE)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

ZapA, a possible virulence factor from Proteus mirabilis exhibits broad protease substrate specificity

The opportunistic bacterium Proteus mirabilis secretes a metalloprotease, ZapA, considered to be one of its virulence factors due to its IgA-degrading activity. However, the substrate specificity of this enzyme has not yet been fully characterized. In the present study we used fluorescent peptides derived from bioactive peptides and the oxidized ß-chain of insulin to determine the enzyme specificity. The bradykinin- and dynorphin-derived peptides were cleaved at the single bonds Phe-Ser and Phe-Leu, with catalytic efficiencies of 291 and 13 mM/s, respectively. Besides confirming already published cleavage sites, a novel cleavage site was determined for the ß-chain of insulin (Val-Asn). Both the natural and the recombinant enzyme displayed the same broad specificity, demonstrated by the presence of hydrophobic, hydrophilic, charged and uncharged amino acid residues at the scissile bonds. Native IgA, however, was resistant to hydrolysis by ZapA.

Proteomic characterization of the multiple forms of the PLAs from the venom of the social wasp Polybia paulista

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

OLIGOSTILBENOIDS FROM GNETUM-VENOSUM

The amazonian climber Gnetum venosum contains, besides the stilbenes resveratrol and rapontigentin (3-methoxyresveratrol), oxidative stilbene oligomers such as the dimer gnetin C and the trimers gnetin E, gnetin J (3''-hydroxygnetin E) and gnetin K (3''-methoxygnetin E). Gnetins J and K are described for the first time. Oligomers of stilbenoids constitute a new class of condensed tannins.

Photo-induced effects in Ge25Ga10S65 glasses studied by XPS and XAS

The present paper focuses on the structural, electronic, and compositional properties of Ge25Ga10S65 glasses before and after UV illumination in air using X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) techniques. The XPS Ge 3d spectra reveal the existence of Ge-O bonds in the surface region of illuminated glass. In the case of this sample, XAS O K-edge spectra showed the formation of an enriched region of oxygen atoms in the glass bulk, indicating a different bonding structure of oxygen at the surface and in the bulk of the glass. Moreover, the structural changes that occur after UV illumination in the glass sample are identified as the formation of a homogeneous germanium oxide surface layer followed by an intermediary Ge25Ga10S65-yOz subsurface region. (c) 2005 Elsevier B.V. All rights reserved.