451 research outputs found
What makes slow samples slow in the Sherrington-Kirkpatrick model
Using results of a Monte Carlo simulation of the Sherrington-Kirkpatrick
model, we try to characterize the slow disorder samples, namely we analyze
visually the correlation between the relaxation time for a given disorder
sample with several observables of the system for the same disorder sample.
For temperatures below but not too low, fast samples (small relaxation
times) are clearly correlated with a small value of the largest eigenvalue of
the coupling matrix, a large value of the site averaged local field probability
distribution at the origin, or a small value of the squared overlap is more robust) . There is a strong correlation between the values of
the relaxation time for two distinct values of the temperature, but this
correlation decreases as the system size is increased. This may indicate the
onset of temperature chaos
Predicting Density and Refractive Index of Ionic Liquids
The determination of the physicochemical properties of ionic liquids (ILs), such as density and refractive index, is essential for the design of processes that involve ILs. Density has been widely studied in ILs because of its importance whereas refractive index has received less attention even though its determination is rapid, highly accurate and needs a small amount of sample in most techniques. Due to the large number of possible cation and anion combinations, it is not practical to use trial and error methods to find a suitable ionic liquid for a given function. It would be preferable to predict physical properties of ILs from their structure. We compile in this work different methods to predict density and refractive index of ILs from literature. Especially, we describe the method developed by the authors in a previous work for predicting density of ILs through their molecular volume. We also correlate our experimental measurements of density and refractive index of ILs in order to predict one of the parameters knowing the other one as a function of temperature. As the measurement of refractive index is very fast and needs only a drop of the ionic liquid, this is also a very useful approach
The Use of Multivariate Analysis in Tropical Grass and Legume Seed Production in Cuban Regions
Seed production is an important activity in developing countries where pastures are the main source for animal feeding (Febles et al. 2003). Another outstanding aspect is the mathematical analysis used when a large number of species, varieties and ecotypes are used in the same study. The objective of this paper was to examine the use of multivariate analysis in studies on the effects of edaphoclimatic factors on seed production from tropical grasses and legumes
Online positive interventions to promote well-being and resilience in the adolescent population: A narrative review
Numerous studies have shown an alarming prevalence of depression, anxiety, and behavior disorders in youth. Thus, prevention of psychological problems in this population becomes crucial. According to the World Health Organization (1), prevention should also include the promotion and development of the individual''s strengths in order to reduce vulnerability to suffering from mental disorders. In addition, other key elements of prevention are the reach, adoption, implementation, and maintenance of interventions. The information and communication technologies, especially the Internet, have much to offer in terms of the prevention and promotion of positive mental health in adolescents. This paper reviews these fields of research-prevention, positive psychology, Internet, and adolescents-and discusses the potential of positive interventions delivered over the Internet as effective and sustainable health promotion tools. The paper provides a brief description of the systems developed so far and a summary of selected features of the studies detected in the literature review. The overall conclusions are that there is a need for more controlled studies with long-term follow-ups, the interventions should be designed considering the specific features of the target users and the specific contexts where the interventions will be delivered, and they could be enhanced by the use of other technologies, such as smartphones, sensors, or social networks
Bird faunas of the humid montane forests of Mesoamerica: biogeographic patterns and priorities for conservation
The distribution of 335 species of birds in 33 islands of humid montane forest in
Mesoamerica is summarized, and patterns of distribution, diversity and endemism are
analysed. The montane forests of Costa Rica and western Panama far exceed other habitat
islands considered for species-richness, richness of species endemic to Mesoamerica,
and richness of species ecologically restricted to humid montane forests. Other regions,
such as the Sierra Madre del Sur of Guerrero and Oaxaca, the Los Tuxtlas region of
southern Veracruz and the mountains of Chiapas and Guatemala, also hold rich and
endemic avifaunas. Based on patterns of similarity of avifaunas, the region can be divided
into seven regions holding distinctive avifaunas (Costa Rica and western Panama;
northern Central America and northern Chiapas; southern Chiapas; eastern Mexico north
of the Isthmus of Tehuantepec; Sierra Madre del Sur; interior Oaxaca; and Transvolcanic
Belt and Sierra Madre Occidental), which serve as useful guides for the setting of
priorities for conservation action.
Se resumen las distribuciones de 335 especies de aves en 33 islas de bosque humedo de
montana en Mesoamerica, y se analizan patrones de distribution, diversidad y
endemismo. Los bosques montanos de Costa Rica y del oeste de Panama tienen la mas
alta riqueza de especies, riqueza de especies endemicas a Mesoamerica, y riqueza de
especies ecologicamente restringidas a bosque humedo de montana. Otras regiones, tales
como la Sierra Madre del Sur de Guerrero y Oaxaca, la region de Los Tuxtlas y las
montanas de Chiapas y Guatemala, tambien tienen avifaunas ricas en especies y en
endemicas. Basado en patrones de similitud de avifaunas, se puede dividir Mesoamerica
en siete regiones que tienen avifaunas distintas (Costa Rica y el oeste de Panama; el
norte de Centroamerica y el norte de Chiapas; el sur de Chiapas; el este de Mexico; la
Sierra Madre del Sur; el interior de Oaxaca; y el Eje Neovolcanico y la Sierra Madre
Occidental), las cuales pueden servir como guias en el establecimiento de prioridades
para la conservation
A numerical study of the overlap probability distribution and its sample-to-sample fluctuations in a mean-field model
In this paper we study the fluctuations of the probability distributions of
the overlap in mean field spin glasses in the presence of a magnetic field on
the De Almeida-Thouless line. We find that there is a large tail in the left
part of the distribution that is dominated by the contributions of rare
samples. Different techniques are used to examine the data and to stress on
different aspects of the contribution of rare samples.Comment: 13 pages, 11 figure
Ecological momentary assessment for chronic pain in fibromyalgia using a smartphone: A randomized crossover study
Background
Daily diaries are a useful way of measuring fluctuations in pain-related symptoms. However, traditional diaries do not assure the gathering of data in real time, not solving the problem of retrospective assessment. Ecological momentary assessment (EMA) by means of electronic diaries helps to improve repeated assessment. However, it is important to test its feasibility in specific populations in order to reach a wider number of people who could benefit from these procedures.
Methods
The present study compares the compliance and acceptability of an electronic diary running on a smartphone using a crossover design for a sample with a specific pain condition, fibromyalgia and low familiarity with technology. Forty-seven participants were randomly assigned to one of two conditions: (1) paper diary smartphone diary and (2) smartphone diary paper diary, using each assessment method for 1 week.
Results
The findings of this study showed that the smartphone diary made it possible to gather more accurate and complete ratings. Besides, this method was well accepted by a sample of patients with fibromyalgia referred by a public hospital, with an important proportion of participants with low level of education and low familiarity with technology.
Conclusions
The findings of this study support the use of smartphones for EMA even in specific populations with a specific pain condition, fibromyalgia and with low familiarity with technology. These methods could help clinicians and researchers to gather more accurate ratings of relevant pain-related variables even in populations with low familiarity with technology.The research presented in this paper was funded in part by Fundacio La Marato de TV3 (Ajuts de la Marato de TV3 2006), Plan de Promocion de la investigacion Universitat Jaume I, (Fundacio Caixa Castello-Bancaixa, P11B2009-30) and by Generalitat Valenciana, Redes de Excelencia ISIC (ISIC/2012/012).Garcia-Palacios, A.; Herrero, R.; Belmonte, M.; Castilla, D.; Guixeres Provinciale, J.; Molinari, G.; Baños, R.... (2014). Ecological momentary assessment for chronic pain in fibromyalgia using a smartphone: A randomized crossover study. European Journal of Pain. 18(6):862-872. https://doi.org/10.1002/j.1532-2149.2013.00425.xS86287218
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