1,097 research outputs found

    Ovarian Carcinoma - Early Detection and Prognostication

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    Linear Relationship between Resilience, Learning Approaches, and Coping Strategies to Predict Achievement in Undergraduate Students

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    This research has been developed within the framework of the R & D Projects EDU2011-24805 (2011-2015) (MICIN, Spain). See:- http://www.estres.investigacion-psicopedagogica.org/englishThe aim of the present research was to analyze the linear relationship between resilience (meta-motivational variable), learning approaches (meta-cognitive variables), strategies for coping with academic stress (meta-emotional variable) and academic achievement, necessary in the context of university academic stress. A total of 656 students from a southern university in Spain completed different questionnaires: a resiliency scale, a coping strategies scale, and a study process questionnaire. Correlations and structural modeling were used for data analyses. There was a positive and significant linear association showing a relationship of association and prediction of resilience to the deep learning approach, and problem-centered coping strategies. In a complementary way, these variables positively and significantly predicted the academic achievement of university students. These results enabled a linear relationship of association and consistent and differential prediction to be established among the variables studied. Implications for future research are set out

    Capital budgeting practices in Spain

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    Producción CientíficaThis paper seeks to shed further light on the capital budgeting techniques used by Spanish companies. Our paper posits that the gap between theory and practice might be related to the nature of sources of value and to the efficiency of mechanisms aligning managerial and shareholder incentives, rather than to resource restrictions or model misinterpretation. We analyze data from a survey conducted in 2011, the final sample comprising 140 non-financial Spanish firms. Our findings show a behaviour pattern similar to that reported in prior research for firms in other countries. Particularly noteworthy is that payback appears to be the most widely used tool, while real options are used relatively little. Our results confirm that size and industry are related to the frequency of use of certain capital budgeting techniques. Further, we find that the relevance of growth opportunities and flexibility is an important factor explaining the use of real options.This work has benefited from financial support from the Spanish Ministry ofScience and Innovation (grant ref. ECO2011-29144-C03-01) and the Program of Advanced Human Capital Formation, Ministry of Education,Government of Chile. The authors assume all responsibility for any errors in this work

    Silencing of genes involved in Anaplasma marginale-tick interactions affects the pathogen developmental cycle in Dermacentor variabilis

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    <p>Abstract</p> <p>Background</p> <p>The cattle pathogen, <it>Anaplasma marginale</it>, undergoes a developmental cycle in ticks that begins in gut cells. Transmission to cattle occurs from salivary glands during a second tick feeding. At each site of development two forms of <it>A. marginale </it>(reticulated and dense) occur within a parasitophorous vacuole in the host cell cytoplasm. However, the role of tick genes in pathogen development is unknown. Four genes, found in previous studies to be differentially expressed in <it>Dermacentor variabilis </it>ticks in response to infection with <it>A. marginale</it>, were silenced by RNA interference (RNAi) to determine the effect of silencing on the <it>A. marginale </it>developmental cycle. These four genes encoded for putative glutathione S-transferase (GST), salivary selenoprotein M (SelM), H+ transporting lysosomal vacuolar proton pump (vATPase) and subolesin.</p> <p>Results</p> <p>The impact of gene knockdown on <it>A. marginale </it>tick infections, both after acquiring infection and after a second transmission feeding, was determined and studied by light microscopy. Silencing of these genes had a different impact on <it>A. marginale </it>development in different tick tissues by affecting infection levels, the densities of colonies containing reticulated or dense forms and tissue morphology. Salivary gland infections were not seen in any of the gene-silenced ticks, raising the question of whether these ticks were able to transmit the pathogen.</p> <p>Conclusion</p> <p>The results of this RNAi and light microscopic analyses of tick tissues infected with <it>A. marginale </it>after the silencing of genes functionally important for pathogen development suggest a role for these molecules during pathogen life cycle in ticks.</p

    Copy number signatures for early diagnosis of high-grade serous ovarian carcinoma

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    BackgroundThe detection of ovarian carcinoma-derived somatic mutations in cervical samples and uterine lavages in several studies since 2013, has brought hope for the development of new biomarkers for early detection. High-grade serous ovarian carcinoma (HGSC) is strongly dominated by copy number alterations (CNAs). These CNAs are the consequence of underlying mutational processes in HGSC. We interrogated CNAs from low coverage whole-genome sequencing (WGS) data in HGSC tumors, plasma, endometrial biopsies, and cervical samples to explore if copy number signatures can be used as a biomarker for early detection of HGSC.Methods A total of 204 samples were included from 18 patients with HGSC, four BRCA mutation carriers and seven benign controls. Estimations of ploidy and cellularity, and thus calculation of absolute copy number, were optimized through a combination of the ACE, Rascal, and ichorCNA bioinformatic tools. Mixture modelling was used to subgroup the six fundamental copy number features and non-negative matrix factorization was used to generate the signatures and cluster the samples.ResultsWe extracted six fundamental copy number features from 69 diagnostic and pre-diagnostic cervical samples from patients diagnosed with HGSC and generated six CN signatures. We found different distributions of features in benign samples compared to tumors and cervical samples from HGSC patients. We also observed different exposures to the six signatures in different patient groups.ConclusionsFurther understanding of the components and cell types contributing to each signature, and inclusion of more cervical samples into the approach, will hopefully identify a novel tumorigenic signature for early detection of HGSC in cervical samples

    On-POM Ring-Opening Polymerisation of N-Carboxyanhydrides

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    The ring-opening polymerisation of a-amino acid N-carboxyanhydrides (NCAs) offers a simple and scalable route to polypeptides with predicted and narrow molecular weight distributions. Here we show how polyoxometalates (POMs)-redox-active molecular metal-oxide anions-can serve as inorganic scaffold initiators for such NCA polymerisations. This "On-POM polymerisation" strategy serves as an innovative platform to design hybrid materials with additive or synergistic properties stemming from the inorganic and polypeptide component parts. We have used this synthetic approach to synthesise a library of bactericidal poly(lysine)-POM hybrid derivatives that can be used to prevent biofilm formation. This versatile "On-POM polymerisation" method provides a flexible synthetic approach for combining inorganic scaffolds with amino acids, and the potential to tailor and improve the specificity and performance of hybrid antimicrobial materials

    The influence of maternal respiratory allergy on obstetrics and perinatal outcomes: a nested case–control study

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    Objective: To evaluate the influence of respiratory allergy on obstetrics and perinatal outcomes. Methods: A nested case–control retrospective study on 41 035 pregnant women. Obstetrics and perinatal outcomes of women with or without respiratory allergy were compared. Rates of preterm delivery (<37 weeks of gestation), low birth weight (<2500 g), neonatal acidosis (pH < 7.20), low 5-min APGAR score (<7), cesarean section rate and indications, and perinatal morbidity and mortality were analyzed. Results are expressed as number and percentages. χ2 and Fisher exact tests were used for comparisons. Logistic regression was used. Statistical significance was set at 95% level (P < 0.05). Results: A total of 724 (1.8%) patients had respiratory allergy, and their rates of preterm delivery and low birth weight were significantly higher than those of control women (both P < 0.001). Nevertheless, analyzing the causes, multiple gestation rate was significantly higher in this group, and adjusting by this, no statistical difference was found in any of the perinatal outcomes studied. In addition, in vitro fertilization and sterility were also significantly higher in the respiratory allergy group (both P < 0.001). Conclusion: Women with respiratory allergy are at higher risks of prematurity and low birth weight but these results are mediated by sterility, in vitro fertilization, and multiple gestation rate. Nonetheless, participation of inflammatory mechanisms should be further studiedThis study did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sector

    Heavy metals in soil treated with sewage sludge composting, their effects on yield and uptake of broad bean seeds (Vicia faba, L.)

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    The final use that may be given to biosolids that result from the treatment of residual municipal waters depends on their physicochemical and microbiological characteristics. Their organic matter content and wealth of essential elements may allow their use for agricultural fertilization purposes. The objective of this research project was to evaluate the physicochemical interactions between soil treated with biosolids and compost from municipal residual waters, and the nutritional parameters of broad bean seeds (Vicia faba L.). The studied area is located in the central region of the Mexican Republic. The biosolids were treated with aerated static pile composting. The experimental work was performed in the area surrounding the East Toluca Macroplant, where nine 2 × 3m plots were defined and distributed in a Latin square; 3 plots were used as controls (without conditioning), 3 were conditioned with 4.5Mgha−1 of biosolids on a dry base, and 3 were conditioned with the same amount of compost. The parameters determined for biosolids, compost, and soil were: pH, electrical conductivity (EC), organic matter (OM), total nitrogen, available phosphorus, cation exchange capacity (CEC), exchangeable cations (Ca, Mg, Na and K), total and available heavy metals (Cd, Cr, Cu, Ni and Zn); for the plant: height reached, green seeds productivity and yield per treatment (ton ha−1); for the seeds: humidity, ashes, fiber, fats, protein, starch and total and available heavy metals (Cd, Cr, Cu, Ni and Zn). pH was slightly acid in soil treated with biosolids (6.71). OM and CEC did not represent significant differences. Total concentrations of Cr, Zn, Ni and Cu in soil presented significant differences (p < 0.05) between treated soil and the control, Cd was not detected. Cu was the most available metal in soil treated with compost (15.31%), Cd and Cr were not detected. The plants had higher growth rates with biosolids (112.22 cm) and compost (103.73 cm); higher Green broad bean productivity and higher seed yield, especially in plots containing biosolids, which had rates three times higher than the control. In regards to broad bean seeds, content of ashes, fiber, fats, protein, starch and heavy metals (Cu, Ni and Zn), there were no significant differences between the treatments. Cd and Cr were not detected. In conclusion, it has been proven that the use of biosolids and compost studied in this broad bean crop do not involve an environmental risk, and thus give way to a solution to the problem of final disposition of biosolids in the region

    Повышение эффективности работы газораспределительных станций путем утилизации энергии природного газа в системе газораспределения

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    Турбодетандеры – это турбомашины, у которых за счет расширения газообразного рабочего тела (природного газа) вырабатывается механическая энергия. Их использование позволяет увеличить эффективность работы газового комплекса за счет выработки электроэнергии. Актуальность работы по созданию энергосберегающих технологий с использованием турбодетандеров как за счет увеличения эффективности технологических схем подготовки газа, так и внедрения новых, более совершенных конструкций проточных частей этих машин, обусловлена достижением существенного экономического эффекта. Целью магистерской диссертационной работы является создание новых принципиальных технологических схем с использованием турбодетандеров в системе распределения природного газа, разработке новых конструкций.Turboexpanders - turbomachines in which mechanical energy is produced by expanding the gaseous working fluid (natural gas). Their use makes it possible to increase the efficiency of the gas complex by generating electricity. The urgency of work on the creation of energy-saving technologies with the use of turbo expanders, both due to the increase in the efficiency of technological schemes for gas preparation, and the introduction of new, more sophisticated designs of the flow parts of these machines, is due to the achievement of a significant economic effect. The purpose of this dissertation work is the creation of new principle technological schemes using turboexpanders in the distribution system of natural gas, the development of new designs

    The Metabolic Core and Catalytic Switches Are Fundamental Elements in the Self-Regulation of the Systemic Metabolic Structure of Cells

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    [Background] Experimental observations and numerical studies with dissipative metabolic networks have shown that cellular enzymatic activity self-organizes spontaneously leading to the emergence of a metabolic core formed by a set of enzymatic reactions which are always active under all environmental conditions, while the rest of catalytic processes are only intermittently active. The reactions of the metabolic core are essential for biomass formation and to assure optimal metabolic performance. The on-off catalytic reactions and the metabolic core are essential elements of a Systemic Metabolic Structure which seems to be a key feature common to all cellular organisms. [Methodology/Principal Findings] In order to investigate the functional importance of the metabolic core we have studied different catalytic patterns of a dissipative metabolic network under different external conditions. The emerging biochemical data have been analysed using information-based dynamic tools, such as Pearson's correlation and Transfer Entropy (which measures effective functionality). Our results show that a functional structure of effective connectivity emerges which is dynamical and characterized by significant variations of bio-molecular information flows. [Conclusions/Significance] We have quantified essential aspects of the metabolic core functionality. The always active enzymatic reactions form a hub –with a high degree of effective connectivity- exhibiting a wide range of functional information values being able to act either as a source or as a sink of bio-molecular causal interactions. Likewise, we have found that the metabolic core is an essential part of an emergent functional structure characterized by catalytic modules and metabolic switches which allow critical transitions in enzymatic activity. Both, the metabolic core and the catalytic switches in which also intermittently-active enzymes are involved seem to be fundamental elements in the self-regulation of the Systemic Metabolic Structure.Consejo Superior de Investigaciones Cientificas (CSIC),grant 201020I026. Ministerio de Ciencia e Innovacion (MICINN). Programa Ramon y Cajal. Campus de Excelencia Internacional CEI BioTIC GENIL, grant PYR-2010-14. Junta de Andalucia, grant P09-FQM-4682
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