86 resultados para Comparative achievement
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In this paper we present: 1. The available data on comparative gender inequality at themacroeconomic level and 2. Gender inequality measures at the microeconomic and case studylevel. We see that market openness has a significant effect on the narrowing of the human capitalgender gap. Globalization and market openness stand as factors that improve both the humancapital endowments of women and their economic position. But we also see that the effects ofculture and religious beliefs are very different. While Catholicism has a statistically significantinfluence on the improvement of the human capital gender gap, Muslim and Buddhist religiousbeliefs have the opposite effect and increase human capital gender differences.In the second global era, some Catholic Latin American countries benefited from market opennessin terms of the human capital and income gender gap, whereas we find the opposite impact inBuddhist and Muslim countries like China and South Korea where women s economic positionhas worsened in terms of human capital and wage inequality.
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The distribution patterns of benthic algal assemblages in the Tinto, Odiel and Piedras rivers were analyzed during the winter of 2005 in 18 sampling stations. The main objective was to assess and compare the algal communities and parameters affecting them both in the zones affected by acid mine drainage (AMD) and in naturally alkaline waters. A total of 108 benthic diatom taxa and 31 non-diatom taxa were identi ed. Results showed large differences between algal communities in the two environments: Pinnularia acoricola, P. subcapitata and Eunotia exigua were the most frequent diatom taxa in regions affected by acid mine drainage, along with algae like Klebsormidium and Euglena mutabilis were the most relevant non-diatom taxa. In alkaline waters the dominant diatom taxa were Planothidium frequentissimum, Gomphonema angustum, Fragilaria capucina, and some species of Navicula (N. viridula, N. veneta or N. radiosa), accompanied by Oscillatoria and Anabaena as well as by streptophytes of the group of zygnemataceae and desmidiaceae
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Background: Drug dosing errors are common in renal-impaired patients. Appropriate dosing adjustment and drug selection is important to ensure patients" safety and to avoid adverse drug effects and poor outcomes. There are few studies on this issue in community pharmacies. The aims of this study were, firstly, to determine the prevalence of dosing inadequacy as a consequence of renal impairment in patients over 65 taking 3 or more drug products who were being attended in community pharmacies and, secondly, to evaluate the effectiveness of the community pharmacist"s intervention in improving dosing inadequacy in these patients when compared with usual care. Methods: The study was carried out in 40 Spanish community pharmacies. The study had two phases: the first, with an observational, multicentre, cross sectional design, served to determine the dosing inadequacy, the drug-related problems per patient and to obtain the control group. The second phase, with a controlled study with historical control group, was the intervention phase. When dosing adjustments were needed, the pharmacists made recommendations to the physicians. A comparison was made between the control and the intervention group regarding the prevalence of drug dosing inadequacy and the mean number of drug-related problems per patient. Results: The mean of the prevalence of drug dosing inadequacy was 17.5% [95% CI 14.6-21.5] in phase 1 and 15.5% [95% CI 14.5-16.6] in phase 2. The mean number of drug-related problems per patient was 0.7 [95% CI 0.5-0.8] in phase 1 and 0.50 [95% CI 0.4-0.6] in phase 2. The difference in the prevalence of dosing inadequacy between the control and intervention group before the pharmacists" intervention was 0.73% [95% CI (−6.0) - 7.5] and after the pharmacists" intervention it was 13.5% [95% CI 8.0 - 19.5] (p < 0.001) while the difference in the mean of drug-related problems per patient before the pharmacists" intervention was 0.05 [95% CI( -0.2) - 0.3] and following the intervention it was 0.5 [95% CI 0.3 - 0.7] (p < 0.001). Conclusion: A drug dosing adjustment service for elderly patients with renal impairment in community pharmacies can increase the proportion of adequate drug dosing, and improve the drug-related problems per patient. Collaborative practice with physicians can improve these results.
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A comparative study of the parts played by technetium-99m diphosphonate and gallium-67 citrate bone scanning in the early diagnosis of infectious spondylodiscitis is presented. Nineteen patients were included in the study. All patients (11 men aged 19-70 years and eight women aged 18-72 years) had a history of back pain varying in duration from one to 15 weeks. A 99mTc diphosphonate bone scan was positive in 17 patients. The two patients with negative results had less than two weeks of back pain. The 67Ga citrate bone scan showed uptake in all patients.
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Evidence exists that many natural facts are described better as a fractal. Although fractals are very useful for describing nature, it is also appropiate to review the concept of random fractal in finance. Due to the extraordinary importance of Brownian motion in physics, chemistry or biology, we will consider the generalization that supposes fractional Brownian motion introduced by Mandelbrot.The main goal of this work is to analyse the existence of long range dependence in instantaneous forward rates of different financial markets. Concretelly, we perform an empirical analysis on the Spanish, Mexican and U.S. interbanking interest rate. We work with three time series of daily data corresponding to 1 day operations from 28th March 1996 to 21st May 2002. From among all the existing tests on this matter we apply the methodology proposed in Taqqu, Teverovsky and Willinger (1995).
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Surfactants are used as additives in topical pharmaceuticals and drug delivery systems. The biocompatibility of amino acid-based surfactants makes them highly suitable for use in these fields, but tests are needed to evaluate their potential toxicity. Here we addressed the sensitivity of tumor (HeLa, MCF-7) and non-tumor (3T3, 3T6, HaCaT, NCTC 2544) cell lines to the toxic effects of lysine-based surfactants by means of two in vitro endpoints (MTT and NRU). This comparative assay may serve as a reliable approach for predictive toxicity screening of chemicals prior to pharmaceutical applications. After 24-h of cell exposure to surfactants, differing toxic responses were observed. NCTC 2544 and 3T6 cell lines were the most sensitive, while both tumor cells and 3T3 fibroblasts were more resistant to the cytotoxic effects of surfactants. IC50-values revealed that cytotoxicity was detected earlier by MTT assay than by NRU assay, regardless of the compound or cell line. The overall results showed that surfactants with organic counterions were less cytotoxic than those with inorganic counterions. Our findings highlight the relevance of the correct choice and combination of cell lines and bioassays in toxicity studies for a safe and reliable screen of chemicals with potential interest in pharmaceutical industry.
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Complexity of biological function relies on large networks of interacting molecules. However, the evolutionary properties of these networks are not fully understood. It has been shown that selective pressures depend on the position of genes in the network. We have previously shown that in the Drosophila insulin/target of rapamycin (TOR) signal transduction pathway there is a correlation between the pathway position and the strength of purifying selection, with the downstream genes being most constrained. In this study, we investigated the evolutionary dynamics of this well-characterized pathway in vertebrates. More specifically, we determined the impact of natural selection on the evolution of 72 genes of this pathway. We found that in vertebrates there is a similar gradient of selective constraint in the insulin/TOR pathway to that found in Drosophila. This feature is neither the result of a polarity in the impact of positive selection nor of a series of factors affecting selective constraint levels (gene expression level and breadth, codon bias, protein length, and connectivity). We also found that pathway genes encoding physically interacting proteins tend to evolve under similar selective constraints. The results indicate that the architecture of the vertebrate insulin/TOR pathway constrains the molecular evolution of its components. Therefore, the polarity detected in Drosophila is neither specific nor incidental of this genus. Hence, although the underlying biological mechanisms remain unclear, these may be similar in both vertebrates and Drosophila.
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Chemoreception is a biological process essential for the survival of animals, as it allows the recognition of important volatile cues for the detection of food, egg-laying substrates, mates or predators, among other purposes. Furthermore, its role in pheromone detection may contribute to evolutionary processes such as reproductive isolation and speciation. This key role in several vital biological processes makes chemoreception a particularly interesting system for studying the role of natural selection in molecular adaptation. Two major gene families are involved in the perireceptor events of the chemosensory system: the odorant-binding protein (OBP) and chemosensory protein (CSP) families. Here, we have conducted an exhaustive comparative genomic analysis of these gene families in twenty Arthropoda species. We show that the evolution of the OBP and CSP gene families is highly dynamic, with a high number of gains and losses of genes, pseudogenes and independent origins of subfamilies. Taken together, our data clearly support the birth-and-death model for the evolution of these gene families with an overall high gene-turnover rate. Moreover, we show that the genome organization of the two families is significantly more clustered than expected by chance and, more important, that this pattern appears to be actively maintained across the Drosophila phylogeny. Finally, we suggest the homologous nature of the OBP and CSP gene families, dating back their MRCA (most recent common ancestor) to 380¿420 Mya, and we propose a scenario for the origin and diversification of these families.
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Background: Chemoreception is a widespread mechanism that is involved in critical biologic processes, including individual and social behavior. The insect peripheral olfactory system comprises three major multigene families: the olfactory receptor (Or), the gustatory receptor (Gr), and the odorant-binding protein (OBP) families. Members of the latter family establish the first contact with the odorants, and thus constitute the first step in the chemosensory transduction pathway.Results: Comparative analysis of the OBP family in 12 Drosophila genomes allowed the identification of 595 genes that encode putative functional and nonfunctional members in extant species, with 43 gene gains and 28 gene losses (15 deletions and 13 pseudogenization events). The evolution of this family shows tandem gene duplication events, progressive divergence in DNA and amino acid sequence, and prevalence of pseudogenization events in external branches of the phylogenetic tree. We observed that the OBP arrangement in clusters is maintained across the Drosophila species and that purifying selection governs the evolution of the family; nevertheless, OBP genes differ in their functional constraints levels. Finally, we detect that the OBP repertoire evolves more rapidly in the specialist lineages of the Drosophila melanogaster group (D. sechellia and D. erecta) than in their closest generalists.Conclusion: Overall, the evolution of the OBP multigene family is consistent with the birth-and-death model. We also found that members of this family exhibit different functional constraints, which is indicative of some functional divergence, and that they might be involved in some of the specialization processes that occurred through the diversification of the Drosophila genus.
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We conduct a large-scale comparative study on linearly combining superparent-one-dependence estimators (SPODEs), a popular family of seminaive Bayesian classifiers. Altogether, 16 model selection and weighing schemes, 58 benchmark data sets, and various statistical tests are employed. This paper's main contributions are threefold. First, it formally presents each scheme's definition, rationale, and time complexity and hence can serve as a comprehensive reference for researchers interested in ensemble learning. Second, it offers bias-variance analysis for each scheme's classification error performance. Third, it identifies effective schemes that meet various needs in practice. This leads to accurate and fast classification algorithms which have an immediate and significant impact on real-world applications. Another important feature of our study is using a variety of statistical tests to evaluate multiple learning methods across multiple data sets.
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Evidence exists that many natural facts are described better as a fractal. Although fractals are very useful for describing nature, it is also appropiate to review the concept of random fractal in finance. Due to the extraordinary importance of Brownian motion in physics, chemistry or biology, we will consider the generalization that supposes fractional Brownian motion introduced by Mandelbrot.The main goal of this work is to analyse the existence of long range dependence in instantaneous forward rates of different financial markets. Concretelly, we perform an empirical analysis on the Spanish, Mexican and U.S. interbanking interest rate. We work with three time series of daily data corresponding to 1 day operations from 28th March 1996 to 21st May 2002. From among all the existing tests on this matter we apply the methodology proposed in Taqqu, Teverovsky and Willinger (1995).
Resumo:
A comparative study of the parts played by technetium-99m diphosphonate and gallium-67 citrate bone scanning in the early diagnosis of infectious spondylodiscitis is presented. Nineteen patients were included in the study. All patients (11 men aged 19-70 years and eight women aged 18-72 years) had a history of back pain varying in duration from one to 15 weeks. A 99mTc diphosphonate bone scan was positive in 17 patients. The two patients with negative results had less than two weeks of back pain. The 67Ga citrate bone scan showed uptake in all patients.
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Background: The combination of oleoyl-estrone (OE) and a selective b3-adrenergic agonist (B3A; CL316,243) treatment in rats results in a profound and rapid wasting of body reserves (lipid). Methods: In the present study we investigated the effect of OE (oral gavage) and/or B3A (subcutaneous constant infusion) administration for 10 days to overweight male rats, compared with controls, on three distinct white adipose tissue (WAT) sites: subcutaneous inguinal, retroperitoneal and epididymal. Tissue weight, DNA (and, from these values cellularity), cAMP content and the expression of several key energy handling metabolism and control genes were analyzed and computed in relation to the whole site mass. Results: Both OE and B3A significantly decreased WAT mass, with no loss of DNA (cell numbers). OE decreased and B3A increased cAMP. Gene expression patterns were markedly different for OE and B3A. OE tended to decrease expression of most genes studied, with no changes (versus controls) of lipolytic but decrease of lipogenic enzyme genes. The effects of B3A were widely different, with a generalized increase in the expression of most genes, including the adrenergic receptors, and, especially the uncoupling protein UCP1. Discussion: OE and B3A, elicit widely different responses in WAT gene expression, end producing similar effects, such as shrinking of WAT, loss of fat, maintenance of cell numbers. OE acted essentially on the balance of lipolysislipogenesis and the blocking of the uptake of substrates; its decrease of synthesis favouring lipolysis. B3A induced a shotgun increase in the expression of most regulatory systems in the adipocyte, an effect that in the end favoured again the loss of lipid; this barely selective increase probably produces inefficiency, which coupled with the increase in UCP1 expression may help WAT to waste energy through thermogenesis. Conclusions: There were considerable differences in the responses of the three WAT sites. OE in general lowered gene expression and stealthily induced a substrate imbalance. B3A increasing the expression of most genes enhanced energy waste through inefficiency rather than through specific pathway activation. There was not a synergistic effect between OE and B3A in WAT, but their combined action increased WAT energy waste.
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The origin of magnetic coupling in KNiF3 and K2 NiF4 is studied by means of an ab initio cluster model approach. By a detailed study of the mapping between eigenstates of the exact nonrelativistic and spin model Hamiltonians it is possible to obtain the magnetic coupling constant J and to compare ab initio cluster-model values with those resulting from ab initio periodic Hartree-Fock calculations. This comparison shows that J is strongly determined by two-body interactions; this is a surprising and unexpected result. The importance of the ligands surrounding the basic metal-ligand-metal interacting unit is reexamined by using two different partitions and the constrained space orbital variation method of analysis. This decomposition enables us to show that this effect is basically environmental. Finally, dynamical electronic correlation effects have found to be critical in determining the final value of the magnetic coupling constant.