1,143 research outputs found
Gauge invariant fluctuations of the metric during inflation from new scalar-tensor Weyl-Integrable gravity model
We investigate gauge invariant scalar fluctuations of the metric during
inflation in a non-perturbative formalism in the framework of a recently
introduced scalar-tensor theory of gravity formulated on a Weyl-Integrable
geometry. We found that the Weyl scalar field can play the role of the inflaton
field in this theory. As an application we study the case of a power law
inflation. In this case the quasi-scale invariance of the spectrum for scalar
fluctuations of the metric is achieved for determined values of the
parameter of the scalar-tensor theory. In our formalism the physical inflaton
field has a geometrical origin.Comment: 9 pages, no figures. This is a revised version accepted for
publication in Physical Review
Modified Brans-Dicke theory of gravity from five-dimensional vacuum
We investigate, in the context of five-dimensional (5D) Brans-Dicke theory of
gravity, the idea that macroscopic matter configurations can be generated from
pure vacuum in five dimensions, an approach first proposed in the framework of
general relativity. We show that the 5D Brans-Dicke vacuum equations when
reduced to four dimensions lead to a modified version of Brans-Dicke theory in
four dimensions (4D). As an application of the formalism, we obtain two
five-dimensional extensions of four-dimensional O'Hanlon and Tupper vacuum
solution and show that they lead two different cosmological scenarios in 4D.Comment: 9 page
Effect of Rosmarinus Officinalis Essential Oil On Anxiety, Depression, And Sleep Quality
Introduction: The objective of this investigation was to evaluate the effect of Rosmarinus officinalis essential oil on anxiety, depression, and sleep quality. Methods: The essential oils were extracted by hydro-distillation using a modified Clevenger-type apparatus and the chemical composition was performed by Gas chromatography with flame ionization detection (GC-FID) and Gas chromatography mass spectrometry (GC–MS). Furthermore, a quasi-experimental study was conducted, where 81 participants were divided into two groups, comprising a waiting list control group and an experimental group treated with essential oils. Anxiety and depression indexes were evaluated using the Zung Self-Rating Anxiety Scale (SAS) and the Zung Self-Rating Depression Scale (SDS), and sleep quality was measured with the Pittsburgh Sleep Quality Inventory (PSQI). Results: Chemical analysis showed that 1,8 cineole (37.6%), α-pinene (19.9%), and linalool (15.8%) were the main components. Anxiety, depression, and sleep quality scores showed a decrease in the post-test study phase compared to the pre-test in the experimental group (p<0.05). A large size effect was found in the case of anxiety (d = 1.491; g= 1.490) with 1-β=0.996, while medium size effects were observed for depression (d = 0.581; g= 0.582) with 1-β=0.585; and sleep quality (d = 0.586; g = 0.588) with 1-β=0.638. Conclusion: Essential oils extracted from Rosmarinus officinalis are more effective in calming anxiety and show moderate changes in depression and sleep quality
Excess Enthalpies of Binary and Ternary Mixtures Containing Dibutyl Ether, Cyclohexane, and 1-Butanol at 298.15 K
Experimental excess enthalpies of the ternary system dibutyl ether (DBE) + cyclohexane + 1-butanol and
the corresponding binary systems at 298.15 K are reported. A quasi-isothermal flow calorimeter has been
built and tested to make the measurements. All the binary and the ternary systems show endothermic character.
The experimental data have been fitted using a polynomial equation for the binary and ternary systems. The
values of the standard deviation indicate good agreement between the experimental results and those calculated
from the equation.Ministerio de Educación y Ciencia, Spain, Projects ENE2006-
12620 and ENE2006-13349, and from the Consejería de Educación,
Junta de Castilla y León, Spain, Project BU015A0
Inducing the cosmological constant from five-dimensional Weyl space
We investigate the possibility of inducing the cosmological constant from
extra dimensions by embedding our four-dimensional Riemannian space-time into a
five-dimensional Weyl integrable space. Following approach of the induced
matter theory we show that when we go down from five to four dimensions, the
Weyl field may contribute both to the induced energy-tensor as well as to the
cosmological constant, or more generally, it may generate a time-dependent
cosmological parameter. As an application, we construct a simple cosmological
model which has some interesting properties.Comment: 7 page
Catálogo de firmes y unidades de obra con áridos reciclados de Residuos de Construcción y Demolición (RCD)
Application of Decision Theory methods for a Community of Madrid Soil classification case
A land classification method was designed for the Community of Madrid (CM), which has lands suitable for either agriculture use or natural spaces. The process started from an extensive previous CM study that contains sets of land attributes with data for 122 types and a minimum-requirements method providing a land quality classification (SQ) for each land. Borrowing some tools from Operations Research (OR) and from Decision Science, that SQ has been complemented by an additive valuation method that involves a more restricted set of 13 representative attributes analysed using Attribute Valuation Functions to obtain a quality index, QI, and by an original composite method that uses a fuzzy set procedure to obtain a combined quality index, CQI, that contains relevant information from both the SQ and the QI methods
Epidemiology of invasive candidiasis in a surgical intensive care unit: an observational study
Background: Invasive candidiasis (IC) is a frequent and life-threatening infection in critically ill patients. The aim of this study was to evaluate the epidemiology of IC and the antifungal susceptibility of etiological agents in patients admitted to our surgical intensive care unit (SICU) in Spain. Methods: We designed a prospective, observational, single center, population-based study in a SICU. We included all consecutive adult patients (≥18 years old) who had documented IC, either on admission or during their stay, between January 2012 and December 2013. Results: There were a total of 22 episodes of IC in the 1149 patients admitted during the 24-month study. The overall IC incidence was 19.1 cases per 1000 admissions. Thirteen cases of IC (59.1 %) were intra-abdominal candidiasis (IAC) and 9 (40.9 %) were candidemias. All cases of IAC were patients with secondary peritonitis and severe sepsis or septic shock. The overall crude mortality rate was 13.6 %; while, it was 33 % in patients with candidemia. All patients with IAC survived, including one patient with concomitant candidemia. The most common species causing IC was Candida albicans (13; 59.1 %) followed by Candida parapsilosis (5; 22.7 %), and Candida glabrata (2; 9.1 %). There was also one case each (4.5 %) of Candida krusei and Candida tropicalis. Thus, the ratio of non-C. albicans (9) to C. albicans (13) was 1:1.4. There was resistance to fluconazole and itraconazole in 13.6 % of cases. Resistance to other antifungals was uncommon. Conclusions: Candida parapsilosis was the second most common species after C. albicans, indicating the high prevalence of non-C. albicans species in the SICU. Resistance to azoles, particularly fluconazole, should be considered when starting an empirical treatment. Although IAC is a very frequent form of IC in critically ill surgical patients, prompt antifungal therapy and adequate source control appears to lead to a good outcome. However, our results are closely related to our ICU and any generalization must be taken with caution. Therefore, further investigations are needed. Keywords: Intensive care unit, Invasive candidiasis, Candidemia, Antifungal susceptibilit
Desarrollo coordinado de evaluación de competencias en materias de ingeniería
Ponencia presentada en: VIII Jornadas de Innovación Docente de la UBU, Burgos, 5 de abril de 2016, organizadas por el Instituto de Formación e Innovación Educativa-IFIE de la Universidad de Burgo
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