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Abstract  

This paper analyses the scientific output and impact of 731 Ph.D. holders who were awarded their doctorate at Spanish universities between 1990 and 2002. The aim was to identify any differences in the amount of scientific output and the impact of publications, in terms of citations, according to gender. The analysis revealed no significant differences in the amount of scientific output between males and females. However, the proportion of female Ph.D. holders with no postdoctoral output was significantly higher than that of their male counterparts, and the median number of papers published after Ph.D. completion was also lower among women. As regards pre- and postdoctoral research, the data showed that early scientific output may be a good predictor of subsequent productivity in both gender groups. The results also indicated that articles by female Ph.D. holders were cited significantly more often, even when self-citations were excluded.

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Scientometrics
Authors: Maite Barrios, Angel Borrego, Andreu Vilaginés, Candela Ollé, and Marta Somoza

Abstract  

The psychology of tourism is a new, multidisciplinary research field. However, no systematic analyses of the scientific production in this field have been carried out to date. This study presents a bibliometric analysis of the area of psychology of tourism between 1990 and 2005. The evolution of scientific production during this period, Price’s, Lotka’s and Bradford’s laws and citation patterns were studied. The results show a significant growth in the literature on the subject, as well as an increase in coauthorship and institutional collaboration. Bibliometric laws and empiric regularities observed in other disciplines are also present in this new research field.

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Scientometrics
Authors: Anna Villarroya, Maite Barrios, Angel Borrego, and Amparo Frías

Abstract  

In this study we analyse gender equality in the preparation, supervision and defence of PhD theses in Spain in the period 1990–2004. The results indicate a tendency towards greater equality in the number of men and women successfully completing doctoral studies. However, the gender imbalance among thesis supervisors and on thesis assessment boards is more apparent, with a predominance of male academics. Moreover, the gender of the PhD student is clearly related to the gender of the supervisor, and both are related to the gender of the members of the assessment boards of PhD theses in Spain.

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Mass migration was, is, and will always be an important topic of discussion regardless of whether it is economically, socially, or politically motivated. This is certainly a matter of great concern for Romania, currently Europe’s largest sender of migrants to Western Europe. Considering that the educational system should be of the uttermost priority, we addressed the issue of emigration propensity among Romanian teachers making use of data from our own nationwide survey. Bivariate logistic models were employed to identify the main factors behind the emigration decisions of pre-university teachers. Aiming to enrich the narrow economic perspective, we adopted a novelty approach by focusing on an overlooked determinant in emigration research studies, namely ethnicity in relation to nationality. Among Romania’s minorities, Hungarians are the most important ethnic group, accounting for 6.1% of the population, hence we explored their migration behaviour compared to Romanian ethnics. The results from the logistic regression models indicate significant differences regarding the factors that trigger the intention to initiate the emigration process for our subjects, based on their ethnicity. We found that teachers of Hungarian ethnicity display 50.6% less propensity to emigrate compared to the ones of Romanian ethnicity and we were able to shape distinct emigration profiles for the two groups.

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Journal of Thermal Analysis and Calorimetry
Authors: Carmen Rodríguez-Tenreiro, Carmen Alvarez-Lorenzo, Ángel Concheiro, and J. Torres-Labandeira

Abstract  

The interactions between Carbopol and β-cyclodextrin (BCD) or hydroxypropyl-β-cyclodextrin (HPBCD) were studied by differential scanning calorimetry (DSC) and FTIR spectroscopy. Aqueous solutions of both components were desiccated by freeze-drying or heating in an oven (films) at various temperatures. The use of different drying procedures allowed their influence on the interactions to be studied. The evolution of the Carbopol glass-transition was also evaluated by DSC using first heating runs up to different temperatures. Disappearance of the Carbopol glass-transition was observed in the freeze-dried systems prepared with either of the cyclodextrins and in the films that contained HPBCD. The changes in the FTIR band of Carbopol at 1700 cm-1 confirmed the existence of interactions with both cyclodextrins, especially with HPBCD. This information may be useful for optimising the solubilizing capacity and controlled release performance of aqueous Carbopol-cyclodextrin systems.

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Valeria Palermo, Ángel G. Sathicq, Patricia G. Vázquez, Horacio J. Thomas, and Gustavo P. Romanelli

Abstract

In this research, we report the preparation of doped PMo Keggin heteropolyacids where Mo is partially replaced by V, Bi, and Bi–V. These catalysts were characterized by means of ICP-AES analysis, 31P-NMR, UV–visible spectra, FT-IR spectra, thermal analysis, and textural properties. In addition, the activities of the synthesized catalysts were evaluated in the selective oxidation of sulfides to sulfoxides/sulfones. The incorporation of V, Bi and Bi–V into the structure of H3PMo12O40 increases the catalytic activity. The two most active catalysts, those with V and V–Bi were supported on aminopropyl-functionalized silica (SiO2NH2) and they were found to be and efficient heterogeneous catalysts for the selective oxidation of diphenylsulfide to the corresponding sulfoxide/sulfone.

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Abstract  

Pacific Northwest National Laboratory (PNNL) has deployed a large array of radiation portal monitors for the Department of Homeland Security and U.S. Customs and Border Protection. These portal monitors scan incoming vehicles crossing the U.S. border and shipping containers leaving international ports for radioactive material via gamma-ray and neutron detection. Data produced and captured by these systems are recorded for every vehicle related to radiation signature, sensor/system status, local background, as well as a host of other variables. Within the Radiation Portal Monitor Project at PNNL, state-of-health observation and analysis for the whole RPM array using these data to determine functionality and performance is ongoing. Advanced state-of-health analysis and monitoring algorithms are being developed. Preparations are underway to incorporate the more difficult state-of-health monitoring of the mobile RPM and Advanced Spectroscopic Portals.

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Acta Oeconomica
Authors: Jorge de Andrés-Sánchez, Ángel Belzunegui-Eraso, and Francesc Valls-Fonayet

Abstract

The relationship between social expenditure, on the one hand, and poverty or income inequality indicators, on the other, focuses a great interest in the literature on welfare systems. In this paper, we evaluate the efficiency of the social transfer policies of the EU-28 states between 2011 and 2015 using deterministic and stochastic frontier models. Using the fuzzy clustering methods, we identify the patterns in the size of welfare systems, which we measure from the value and efficiency of social expenditure. In this way, we identify four clusters. The first cluster comprises many EU-15 countries (normally the Continental and the Nordic welfare states); the second comprises nations that were integrated into the EU in the last 15 years (mostly the former Communist countries); the third cluster comprises the culturally and geographically heterogeneous countries, such as Hungary, Ireland, Croatia and Luxemburg (whose main characteristic is the high efficiency of their social expenditure); and finally, the fourth group basically comprises the southern European countries, whose social transfer policy effectiveness is rather weak.

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European Journal of Microbiology and Immunology
Authors: Cosme Alvarado-Esquivel, Ángel Osvaldo Alvarado-Félix, and Gustavo Alexis Alvarado-Félix

The epidemiology of Toxocara infection in rural Mexico is largely unknown. Therefore, we sought to determine the seroprevalence of Toxocara infection in rural people in a northern Mexican state. We performed a cross-sectional seroprevalence study of 641 people living in rural Durango State including 282 subjects of the general population, 214 subjects of Huichol ethnicity, and 145 subjects of Mennonite ethnicity. Sera of participants were analyzed for the presence of anti-Toxocara immunoglobulin G (IgG) antibodies using a commercially available enzyme immunoassay. Three (0.5%) of the 641 subjects tested were positive for anti-Toxocara IgG antibodies. Of the 3 Toxocara seropositive subjects, two were females, aged 19 and 39 years, and one was male, aged 59 years. They had contacted with dogs, cleaned cat excrement, consumed unwashed raw fruits, contacted soil, or lived in a house with soil floors. Seroprevalence of Toxocara infection was similar among the 3 groups of population studied: 0.4% for the general population, 0.9% for Huicholes, and 0.0% for Mennonites (P = 0.41). In conclusion, the Toxocara seroprevalence found in subjects in rural Durango is low as compared with those reported in people from rural areas in other countries.

Open access

Abstract  

Advances in liquid scintillation counting (LSC) technologies, such as imporved scintillation cocktail formulations and alpha-beta radiation discrimination, make LSC suitable for applications in uranium process chemistry. Ease of use, low cost, and the huge dynamic range of LSC are distinct advantages for analytical support of actinide processing. All uranium isotopes decay primarily with alpha radiation emission. The immediate short-lived daughters of238U are234Th and234Pa. These nuclides are beta emitters having energy bands that overlap the uranium bands in a liquid scintillation spectrum. The resolution of these overlapping bands by alpha-beta radiation discrimination is useful for uranium quantification and purity verification. Protactinium-234 is a high-energy beta emitter that can be further identified and quantified from it's Cherenkov radiation. Energy spectra were collected on the Packard 2500AB liquid scintillator analyzer for uranyl solutions in diisopropylnaphthalene and pseudocumene based scintillator cocktails. Calibration curves were prepared for nitric, hydrochloric, and sulfuric acid media. Base titrations demonstrated the effect of acid quenching on those system. Ion exchange and water soluble polymer extraction studies are readily followed using liquid scintillation methods.

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