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In this study, Ti-15Zr-xMo (5, 10, 15, and 20 wt%) alloys were submitted to solution and aging treatments and their effects evaluated in terms of phase composition and selected mechanical properties (Vickers microhardness and Young's modulus) for use as biomedical implants. The solution treatment was performed at 1123 K for 2 h, while aging treatments were carried out at 698 K for 4, 8, and 12 h, followed by water quenching. Phase composition and microstructure were dependent of the heat treatments, with Ti-15Zr-5Mo (α +â€¯ß type) and Ti-15Zr-10Mo (metastable ß type) alloys exhibiting intense α phase precipitation. The α-phase precipitates were related to α″ → α and ß → α phase decompositions. The Ti-15Zr-10Mo alloy exhibited an intermediary isothermal ω-phase precipitation after aging for 4 h. Vickers microhardness and Young's modulus values changed gradually with the amount of α phase. Aged Ti-15Zr-15Mo and Ti-15Zr-20Mo alloys presented better combinations of hardness and Young's modulus than CP-Ti and Ti-64 ELI for biomedical applications.

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Carbofuran is a toxic carbamate pesticide, and its use has increased in recent years. While marketing information indicates stability in different chemical media, carbofuran exhibits relative photolability. The aim of this research was to decompose carbofuran and to identify the photoproducts achieved when two different doped titania photocatalysts were employed under UV irradiation. The iron-doped TiO2 materials were obtained (a) via a hydrothermal method and (b) by an ultrasound-assisted sol-gel method. The precursors were TiOSO4⋅xH2O and Fe3(NO3)·9H2O. X-ray studies confirmed that the anatase phase of the iron-doped TiO2 resulted from the two preparation methods. The photocatalytic performance of the prepared materials was monitored by LC/ESI-QTOF-MS, enabling the identification of photoproducts: oxo-carbamates, hydroxylated benzofuranes, a carboxamide, and one amine. By using the iron-doped TiO2 materials, 2,2-dimethyl-2,3-dihydrobenzofuran-3,7-diol was the most abundant photoproduct, and N,2,2-trimethyl-2,3-dihydrobenzofuran-7-amine was the only compound that had not been previously reported in the photolysis and photocatalysis of carbofuran. The product 3-hydroxy carbofuran, a cholinesterase inhibitor, was quantified and was found to be transformed into compounds that lack this inhibitive property.

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Microcrystals of orthorhombic nickel (II) oxalate dihydrate were synthesized through a precipitation reaction of aqueous solutions of nickel chloride and oxalic acid. Magnetic susceptibility exhibits a sharp peak at 3.3 K and a broad rounded maximum near 43 K. We associated the lower maximum with a metamagnetic transition that occurs when the magnetic field is about ≥3.5 T. The maximum at 43 K is typical of 1D antiferromagnets, whereas weak ferromagnetism behavior was observed in the range of 3.3­43 K.

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Primary Health Care (PHC) is the basic health support that includes health promotion and disease prevention, considering social and developmental factors. It is the main axis to pregestational health programs with the basic elements for the women's self-care. This study evaluated the impact on health behavior and adherence to a community based pregestational preventive program in 224 women of reproductive age from Mexico City. The women were exposed to a health education intervention for twelve months, with free clinical examination every six months in a mobile screening unit close to their homes. Food and hygiene one to one orientation was offered, together with anthropometric, blood pressure and biochemical evaluations. Program adherence was 55%. Most of the women were less than 25 years of age, education above nine years, non-single, housework occupation as housewives, from an extended family, with social security and two or less live children and desire for more. No differences were found in the evaluated factors between those who continued and those who left the program. When comparing initial and final data, a significant larger proportion did breast self-examination, while this was not the case for the Pap smear test, no differences were found in prevalence of anemia or overweight. Drop-out was mainly due to a lack of interest, school or work problems and change of address. While breast self examination showed a positive effect, the negative or no effect on the other factors requires the intervention of other health professionals and implies more effort from the women. If one of the objectives of the PHC is health promotion, nurse intervention is a prominent role in the community.

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Extremely low birth weight infants with chronic lung disease (CLD) have frequent episodes of desaturation (hypoxemia). We quantified oxygenation and episodes of hypoxemia in 55 infants (birth weight < or = 1000 gm) with CLD in the supine versus prone position, for 1-hour time intervals. Oxygen saturation was measured with the Nellcor N-200 pulse oximeter and a computer program. Prone positioning increased oxygen saturation from 92.0% to 94.1% (p < 0.001) and significantly decreased episodes of hypoxemia to oxygen saturation levels of less than 90%, 85%, and 80% (p < 0.001). Our findings support prone positioning for the extremely low birth weight infant with CLD in an intensive care setting.

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The short term effects of norethisterone (NET), progesterone (P), estradiol (E2) and dihydrotestosterone (DHT) on the gonadotropin secretion of pituitary cells, from both male and female rats, in primary culture primed with E2 were studied. In female cells, NET only increased the GnRH-induced secretion of LH, while P increased both LH and FSH. Male pituitary cells showed an increased response to GnRH after P pretreatment only if the E2 concentration was augmented. However with the same E2 conditions pretreatment with NET decreased the stimulated LH, but not FSH secretion. Pretreatment with E2 inhibited LH stimulated secretion from pituitary cells of male but not female rats. Furthermore DHT treatment diminished the GnRH response for both LH and FSH in pituitary cells from both sexes. Androgen pretreatment increased basal gonadotropin secretion in male but not in female cells. Basal FSH secretion was increased by NET pretreatment in male cells. This suggests that NET is metabolized by cultured pituitary cells to A-ring reduced compounds during the 4 h incubation period. The formation of NET metabolites, particularly the 3 beta, 5 alpha and 5 alpha-NET might be responsible for the estrogenic and androgenic effects observed when NET was administered to the cultured pituitary cells.

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