Tecnologia de sementes de espécies florestais nativas da Amazônia.

Laboratório de sementes florestais; Introdução; Estudos de germinação; Tamanho e forma de sementes; Fitopatologia de sementes.bitstream/item/49443/1/fd090001.pdf1 folder

Transesterification Reactions With Mg-0/i-2 For The Synthesis Of Sitophilate, (2r*, 3s*) 1-ethylpropyl-2-methyl-3-hydroxypentanoate, An Aggregation Pheromone For Sitophilus Granarius Linnaeus, 1785 (coleoptera: Curculionidae)

The concern to minimize the environmental impacts caused by the use of pesticides in agriculture has led researchers to develop new pest control methods. Thus, the technology based on the use of pheromones has been noted for being highly specific substances, that is act only on individuals of the same species. In this context, we describe the synthesis of sitophilate, aggregation pheromone of Sitophilus granarius, a important pest of stored cereal grains. The sitophilate was obtained by transesterification of methyl-2-methyl-3-oxopentanoate with 3-pentanol mediated by Mg-0/I-2, with subsequent reduction of the ketone group of 1-ethylpropyl-2-methyl-3-oxopentanoate using NaBH4 in the presence of a Lewis acid (ZnCl2, MgCl2, CaCl2 and MnCl2). The experimental results showed that the MnCl2 is the most effective for the formation of syn diastereoisomers, since these are the compounds that exert biological activity on the insect.32413014

Association of ADAMTS7 gene polymorphism with cardiovascular survival in coronary artery disease

Recent genetic studies have revealed an association between polymorphisms at the ADAMTS7 gene locus and coronary artery disease (CAD) risk. Functional studies have shown that a CAD-associated polymorphism (rs3825807) affects ADAMTS7 maturation and vascular smooth muscular cell (VSMC) migration. Here, we tested whether ADAMTS7 (A/G) SNP is associated with cardiovascular (CV) survival in patients with established CAD. A cohort of 1,128 patients with angiographic proven CAD, who were followed up prospectively for a mean follow-up period of 63 (range 6-182) mo, were genotyped for rs3825807 A/G. Survival statistics (Cox regression) compared heterozygous (AG) and wild-type (AA) with the reference homozygous GG. Kaplan-Meier (K-M) survival curves were performed according to ADAMTS7 genotypes for CV mortality. Results showed that 47.3% of patients were heterozygous (AG), 36.5% were homozygous for the wild-type allele (AA) and only 16.2% were homozygous for the GG genotype. During the follow-up period, 109 (9.7%) patients died, 77 (6.8%) of CV causes. Survival analysis showed that AA genotype was an independent risk factor for CV mortality compared with reference genotype GG (HR = 2.7, P = 0.025). At the end of follow-up, the estimated survival probability (K-M) was 89.8% for GG genotype, 82.2% for AG and 72.3% for AA genotype (P = 0.039). Carriage of the mutant G allele of the ADAMTS7 gene was associated with improved CV survival in patients with documented CAD. The native overfunctional ADAMTS7 allele (A) may accelerate VSMC migration and lead to neointimal thickening, atherosclerosis progression and acute plaque events. ADAMTS7 gene should be further explored in CAD for risk prediction, mechanistic and therapeutic goals.info:eu-repo/semantics/publishedVersio

Evidences for Tsallis non-extensivity on CMR manganites

We found, from the analysis of $M$ vs. $T$ curves of some manganese oxides (manganites), that these systems do not follow the traditional Maxwell-Boltzmann statistics, but the Tsallis statistics, within the \QTR{em}{normalized} formalism. Curves were calculated within the mean field approximation, for various ferromagnetic samples and the results were compared to measurements of our own and to various other authors published data, chosen at random from the literature. The agreement between the experimental data and calculated $M_{q}$ vs. $T^{\ast}$ curve, where $T^{\ast}$ is an effective temperature, is excellent for all the compounds. The entropic parameter, $q$, correlates in a simple way with the experimental value of $T_{c}$, irrespect the chemical composition of the compounds, heat treatment or other details on sample preparation. Examples include $q<1$ (superextensivity), $q=1$ (extensivity) and $q>1$ (subextensivity) cases.Comment: 12 pages, 3 figure

Generalized Second Law and phantom Cosmology: accreting black holes

The accretion of phantom fields by black holes within a thermodynamic context is addressed. For a fluid violating the dominant energy condition, case of a phantom fluid, the Euler and Gibbs relations permit two different possibilities for the entropy and temperature: a situation in which the entropy is negative and the temperature is positive or vice-versa. In the former case, if the generalized second law (GSL) is valid, then the accretion process is not allowed whereas in the latter, there is a critical black hole mass below which the accretion process occurs. In a universe dominated by a phantom field, the critical mass drops quite rapidly with the cosmic expansion and black holes are only slightly affected by accretion. All black holes disappear near the big rip, as suggested by previous investigations, if the GSL is violated.Comment: 8 pp., no figure