In this investigation, pure and gadolinium-doped cobalt ferrites (Co1−xGdxFe2O4+δ, x= 0, 0.02, 0.04, 0.06, 0.08y 0.1), were synthesized through a modified route of the coprecipitation method. X-ray ...diffraction technique shows a cubic phase of the spinel-type structure typically associated with these compounds. According to Scherrer's equation, the crystallite size can be tuned through the Gd3+ content (26nm to x= 0 and 9nm to x= 0.1) or through the temperature of the thermal treatment (21nm to 400°C and 28nm to 700°C). The obtained powders show a ferrimagnetic behavior, at room temperature, with magnetization (reached at the maximum applied field) and coercivity values showing a dependence on the substitution grade of cobalt (II) by gadolinium (III) ions. At x= 0.02 the magnetization shows an increase of 7% (even when the particle size decreases a 40%) and the coercivity shows a decrease of 45%. DC conductivity of sintered ferrites is enhanced up to 3 orders of magnitude in the x= 0.1 substituted materials; while, keeping a constant transverse magneto-optical Kerr effect around 0.35%.
Treatment of sodium N-(o-azidobenzoyl)aminoacylglycinates 8 with acetic anhydride afforded 1-acetyl-4-(o-azidobenzoyl)-2,5-piperazinediones 7, with complete retention of the stereochemistry. The ...intramolecular aza Wittig reactions of compounds 7 in the presence of tributylphosphine followed by deacetylation gave 1,2-unsubstituted pyrazino2,1-bquinazoline-3,6-diones 1. This route was adapted to the synthesis of both enantiomers of the alkaloid glyantrypine.
β-Carboline alkaloids exhibit a great variety of pharmacological activities. The solid inclusion complexes of harmane and harmine with β-cyclodextrin and also with hydroxypropyl-β-cyclodextrin, have ...been prepared following different procedures. IR and NMR spectroscopies were employed to verify the interaction of the guest molecules with the cyclodextrin cavities. The differences observed in the IR and NMR spectra are in agreement with those described in the literature for other guest molecules. The shifts in the
13C- and
1H-NMR spectra confirm the existence of the inclusion complexes. The fluorescence emission spectra of these complexes dissolved in buffered aqueous solution (pH 7.3) exhibit the characteristic peaks of the cationic form for harmane alkaloids. The neutral bands are not present for the free alkaloids in aqueous solutions. Fluorescence quenching emission of the complexes is compared to that of the corresponding free alkaloids.
The excited states of unstable ^{20}O were investigated via γ-ray spectroscopy following the ^{19}O(d,p)^{20}O reaction at 8 AMeV. By exploiting the Doppler shift attenuation method, the lifetimes ...of the 2_{2}^{+} and 3_{1}^{+} states were firmly established. From the γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+} and 3_{1}^{+} states, the B(E2) and B(M1) were determined. Various chiral effective field theory Hamiltonians, describing the nuclear properties beyond ground states, along with a standard USDB interaction, were compared with the experimentally obtained data. Such a comparison for a large set of γ-ray transition probabilities with the valence space in medium similarity renormalization group ab initio calculations was performed for the first time in a nucleus far from stability. It was shown that the ab initio approaches using chiral effective field theory forces are challenged by detailed high-precision spectroscopic properties of nuclei. The reduced transition probabilities were found to be a very constraining test of the performance of the ab initio models.
The mitotic index and tumor size are currently the main prognostic indicators of gastrointestinal stromal tumors (GIST). The purpose of this study is to investigate the expression of different ...immunohistochemical markers and their relation to mortality and relapse, and especially concerning high-risk tumors.
We did a retrospective study of 68 patients who underwent surgery from 1997 to 2007 with a diagnostic of gastrointestinal stromal tumor.
The median follow-up period was 29 months. Relapse and mortality rates were 35.3% (24 cases) and 41.2% (28 cases), respectively. The mitotic index was related to p53 and the cellular proliferation index -Ki67- (p = 0.006 and p = 0.003, respectively). Considering both high and intermediate-risk neoplasms, a significant relation to Ki67 was obtained (p = 0.008). Relapse was related to the mitotic index (p = 0.032) and Ki67 (p = 0.024). Concerning mortality, statistically significant results were obtained with necrosis variables (p = 0.02), mitotic index (p = 0.013), p53 (p = 0.024) and Ki67 (p = 0.033).
Ki67 could be considered a prognostic marker for both relapse and mortality. Concerning high risk GIST, the usefulness the p53 protein and Ki67 nuclear antigen markers was also evident concerning relapse and mortality.
Malformation or dysmorphic syndromes are conditions that are defined by the combination of a set of major and minor malformations that generally have a genetic origin. We investigated the early ...Spanish descriptions of a large number of sydromes.
We started the study from the definition in a classic treatise on the subject. Among the 60 selected syndromes studied, at least two articles of each syndrome among those published in Spain and for the first time were listed in the Spanish Medical Index. For years prior to 1970, it expanded The search was expanded to PubMed, for the years before 1970.
We collected 64 articles that referred to 58 syndromes. Four articles were written during the first half of the twentieth century. Almost half of the works (n=30) appeared in the 1970's. The papers were published in ten Spanish pediatric, nine Spanish non-pediatric, three pediatric non-Spanish and two non-Spanish non-pediatric Journals. The Journals with the most articles published were Anales de Pediatría y Revista Española de Pediatría. The hospitals where the articles originate more often were Hospital La Paz, Madrid and Hospital Clinic, Barcelona. The rest of the works were written in 30 pediatric hospitals and two more in non-Spanish hospitals. The number of authors increased with the passage of time.
Although there were potential limitations, we have identified what may be the first descriptions of 58 syndromes, among the 60 chosen initially.
An efficient methodology based on low temperature microwave-induced pyrolysis has been developed for syngas production from macroalgae. The protocol provided unprecedented hydrogen production, with ...switchable H
2
/CO ratios depending on pyrolysis conditions which were found to remarkably improve conventional pyrolysis experiments even at significantly higher temperatures (400
vs.
800 °C). Arcing effects under microwave irradiation, which result in an interesting observed pseudo-catalytic effect promoted by the metal oxides contained in macroalgae, seem to account for the improved results.
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