1,310 research outputs found
Roughness of Sandpile Surfaces
We study the surface roughness of prototype models displaying self-organized
criticality (SOC) and their noncritical variants in one dimension. For SOC
systems, we find that two seemingly equivalent definitions of surface roughness
yields different asymptotic scaling exponents. Using approximate analytical
arguments and extensive numerical studies we conclude that this ambiguity is
due to the special scaling properties of the nonlinear steady state surface. We
also find that there is no such ambiguity for non-SOC models, although there
may be intermediate crossovers to different roughness values. Such crossovers
need to be distinguished from the true asymptotic behaviour, as in the case of
a noncritical disordered sandpile model studied in [10].Comment: 5 pages, 4 figures. Accepted for publication in Phys. Rev.
Decennial comparison of changes in social vulnerability: a municipal analysis in support of risk management
The concept of Social Vulnerability (SV) is characterized and distinguished by its complexity and multidisciplinarity. This concept takes into account the specific characteristics of the individual and his social and economic relations, as well as the physical environment where he is inserted. These differentiating characteristics make Social Vulnerability (SV) an indispensable work tool in the process of characterizing and understanding the degree of exposure of communities, as well as evaluating their capacity for resilience and recovery from hazardous events.
This paper presents a comparison between the SV performed in 2008 with the results obtained in 2017 for the 278 municipalities of mainland Portugal. The methodology was based on the work developed by the Center for Social Studies of the University of Coimbra, which is distinguished by the fact that SV is composed of two components: Criticity and Support Capability. The analysis of SV and its components was done using Principal Components Analysis (PCA) starting from an initial set of 235 variables (90 for Criticality and 145 for Support Capability).
With respect to Criticality, the results point out the importance of factors related to the economic condition, employment and factors related to the disadvantaged population and risk groups. Support Capability is strongly influenced by the population density and the most relevant factors for the final results are those related to civil protection response, economic and environmental dynamism and logistic and service capacity. Regarding the SV spatial distribution, the highest values are located mainly in the central and northern parts of the country, with emphasis on the Douro river valley and surrounding municipalities; also a general decrease of SV was recorded in the southern regions from 2008 to 2017.info:eu-repo/semantics/publishedVersio
High-pressure Raman study of L-alanine crystal
Pressure-dependent Raman scattering studies in the range 0.0 -- 32 kbar were
carried out in L-alanine in order to investigate its external mode phonon
spectra in relation to the phase transitions in the crystal. A careful analysis
of the spectra shows that the low-energy Raman modes exhibit variation both in
frequency and in intensity and between 26 and 28 kbar it is observed a
splitting of a external mode, indicating that the D_2 normal phase undergoes a
transition. Pressure coefficients for external modes are also given.Comment: 11 pages, Latex, 2 figure
Hierarchy problem and the cosmological constant in a five-dimensional Brans-Dicke brane world model
We discuss a new solution, admitting the existence of dS_{4} branes, in
five-dimensional Brans-Dicke theory. It is shown that, due to a special form of
a bulk scalar field potential, for certain values of the model parameters the
effective cosmological constant can be made small on the brane, where the
hierarchy problem of gravitational interaction is solved. We also discuss new
stabilization mechanism which is based on the use of auxiliary fields.Comment: 11 page
El cruce Alentejano x BÃsaro: un estudio en TREASURE
LBÃsara (BI) son las dos
razas porcinas locales más
importantes de Portugal, contando
con un número de cerdas
reproductoras de cerca de 6.500
(AL) y 5500 (BI) (datos de 2017,
ANCPA y ANCSUB). Desde el
punto de vista genético, fenotÃpico
y de sistema usual de producción,
son muy similares al cerdo Ibérico
y Celta, respectivamente, de
España. AsÃ, la raza Alentejana es
caracterizada por su baja prolificidad
(Nunes, 1993; Charneca et
al., 2012), crecimiento lento
(excepto en montanera, Freitas,
1998) y tipo adipogénico (Neves et
al., 1996). El cerdo BÃsaro tiene
mayor prolificidad (Carolino et al.
2009) y menor adiposidad, pero,
aun teniendo el mismo origen
genético de genotipos ahora
usados en producción intensiva
(ej. Large-White), no fue sometido
a programas de mejora genética,
lo que resulta en un cerdo cuya
productividad está alejada de las
razas mejoradas actuales.
En la primera mitad del
siglo pasado las razas de cerdos
autóctonas eran predominantes
en Portugal (el AL representaba
cerca de 45% del efectivo porcino,
Carvalho, 1964) distribuidos
generalmente en el sur (AL) y en
Centro/Norte (BI) del paÃs. Sin
embargo, en las regiones de
coexistencia (en la región de
Ribatejo, por ejemplo) los ganaderos
hacÃan cruces entre las dos
razas de forma común, para
obtener productos que al parecer
e r a n m u y a p r e c i a d o s .
Desafortunadamente no hay
información zootécnica sobre
esos animales cruzados o sobre
sus productos
High-cell-density fermentation of Saccharomyces cerevisiae for the optimisation of mead production
Mead is a traditional drink that contains 8 % and 18 % (v/v) of ethanol, resulting from the alcoholic fermentation of diluted honey by yeasts. Mead fermentation is a time-consuming process and the quality of the final product is highly variable. Therefore, the present investigation had two main objectives: first, to determine the adequate inoculum size of two commercial wine-making strains of Saccharomyces cerevisiae for the optimisation of mead fermentation; and second, to determine if an increase in yeast pitching rates in batch fermentations altered the resulting aroma profiles. Minor differences were detected in the growth kinetics between the two strains at the lowest pitching rate. With increasing pitching rates net growth of the strain ICV D47 progressively decreased, whereas for the QA23 the increasing inoculum size had no influence on its net growth. The time required to reach the same stage of fermentation ranged from 24 to 96 h depending on the inoculum size. The final aroma composition was dependent on the yeast strain and inoculum size. Fourteen of the twenty-seven volatile compounds quantified could contribute to mead aroma and flavour because their concentrations rose above their respective thresholds. The formation of these compounds was particularly pronounced at low pitching rates, except in mead fermented by strain ICV D47, at 106 CFUs/mL. The esters isoamyl acetate, ethyl octanoate and ethyl hexanoate were the major powerful odourants found in the meads. The results obtained in this study demonstrate that yeast strain and inoculum size can favourably impact mead’s flavour and aroma profiles.The research presented in this paper was partially funded by the Fundacao para a Ciencia e Tecnologia, (FCT) and by PTDC projects (contracts PTDC/AGR-ALI/68284/2006). A.P.P. is a recipient of a Ph.D. grant from FCT (SFRH/BD/45820/2008)
Towards self-organized service-oriented multi-agent systems
The demand for large-scale systems running in complex and even chaotic environments requires the consideration of new paradigms and technologies that provide flexibility, robustness, agility and responsiveness. Multiagents systems is pointed out as a suitable approach to address this challenge by offering an alternative way to design control systems, based on the decentralization of control functions over distributed autonomous and cooperative entities. However, in spite of their enormous potential, they usually lack some aspects related to interoperability, optimization in decentralized structures and truly self-adaptation. This paper discusses a new perspective to engineer adaptive
complex systems considering a 3-layer framework integrating several complementary
paradigms and technologies. In a first step, it suggests the integration of multi-agent systems with service-oriented architectures to overcome the limitations of interoperability and smooth migration, followed by the use of technology
enablers, such as cloud computing and wireless sensor networks, to provide a ubiquitous and reconfigurable environment. Finally, the resulted service-oriented multi-agent system should be enhanced with biologically inspired techniques, namely self-organization, to reach a truly robust, agile and adaptive system
Association Of Inflammation, Dyslipidemia, Obesity And Physical Activity Status In Children
The aim of this study was to verify the association between inflammatory biomarkers, dyslipidemia, obesity and physical activity status in 10-years old children. Ninety-four children participated in this study and were classified into eutrophic (n=36), overweight (n=34) or obese (n=24) according to their body mass index (BMI). The genic expression of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α) and chemokine C-C motif ligand 2 (CCL-2) mRNA; the serum concentration of high-density lipoprotein cholesterol (HDL-c) and triglycerides; BMI, percentage of body fat (% BF) and waist circumference; and the number of steps per day were determined. The expression of IL-6, TNF-α and CCL-2 were associated (p 0.05) between pro-inflammatory biomarkers and number of steps per day was found.222182
- …