3,292 research outputs found
Oral and general health conditions involved in periodontal status during pregnancy: a prospective cohort study
Purpose: Pregnancy is a period in a woman’s life that has important consequences on oral health, particularly for gingival health. Present study aims to identify women at higher risk of developing periodontal disease (gingivitis and periodontitis) during late pregnancy and evaluate how this condition evolves during this period. Methods: Prospective cohort study was designed with pregnant women who were assessed during the first and third trimesters of gestation in a southern Spanish public hospital. Data regarding gingival and periodontal health, oral hygiene, and overall health status (obesity and diabetes mellitus) were collected. Reporting followed STROBE checklist. Results: Significantly higher number of women had the periodontal and gingival disease in the third trimester of gestation compared with in early pregnancy. In the third trimester of gestation, 42 (28.6%) and 63 (42.9%) of women presented symptoms of periodontal disease and gingival disease, respectively. Obesity (OR 2.834; 95%CI 0.919–8.741), worse oral hygiene during the first trimester of gestation (OR: 4.031; 95%CI 2.12–7.65), and periodontal disease during early pregnancy (OR: 15.104; 95%CI 3.60–63.36) most effectively predicted periodontal disease during late pregnancy. Conclusions: Pregnancy is associated with exacerbated periodontal and gingival disease symptoms throughout the different trimesters of gestation. Obesity and oral hygiene during early pregnancy were the risk factors that most contributed to the aforementioned changes in periodontal disease.Ministerio de Ciencia, Innovación y UniversidadesRevisión por pare
A global analysis of field body temperatures of active squamates in relation to climate and behaviour
Aim
Squamate fitness is affected by body temperature, which in turn is influenced by environmental temperatures and, in many species, by exposure to solar radiation. The biophysical drivers of body temperature have been widely studied, but we lack an integrative synthesis of actual body temperatures experienced in the field, and their relationships to environmental temperatures, across phylogeny, behaviour and climate.
Location
Global (25 countries on six continents).
Taxa
Squamates (210 species, representing 25 families).
Methods
We measured the body temperatures of 20,231 individuals of squamates in the field while they were active. We examined how body temperatures vary with substrate and air temperatures across taxa, climates and behaviours (basking and diel activity).
Results
Heliothermic lizards had the highest body temperatures. Their body temperatures were the most weakly correlated with substrate and air temperatures. Body temperatures of non-heliothermic diurnal lizards were similar to heliotherms in relation to air temperature, but similar to nocturnal species in relation to substrate temperatures. The correlation of body temperature with air and substrate temperatures was stronger in diurnal snakes and non-heliothermic lizards than in heliotherms. Body-substrate and body-air temperature correlations varied with mean annual temperatures in all diurnal squamates, especially in heliotherms. Thermal relations vary with behaviour (heliothermy, nocturnality) in cold climates but converge towards the same relation in warm climates. Non-heliotherms and nocturnal species body temperatures are better explained by substrate temperature than by air temperature. Body temperature distributions become left-skewed in warmer-bodied species, especially in colder climates.
Main Conclusions
Squamate body temperatures, their frequency distributions and their relation to environmental temperature, are globally influenced by behavioural and climatic factors. For all temperatures and climates, heliothermic species' body temperatures are consistently higher and more stable than in other species, but in regions with warmer climate these differences become less pronounced. A comparable variation was found in non-heliotherms, but in not nocturnal species whose body temperatures were similar to air and substrate irrespective of the macroclimatic context
Influence of system dynamics in brake blending strategies for electric vehicles
Regenerative and friction braking blending strategies need to consider both system dynamics in order to optimize their performance. Usually, the priority in electric vehicles is battery regeneration through electric braking instead of friction braking. This work studies the dynamics of both systems and proposes an optimized brake-blending strategy. The goal is to maximize regeneration without affecting safety. Both dynamics are studied separately with commercial systems: electric drivetrain and friction brake-by-wire. The proposed strategy takes into account temporary response as well as the physical limitations of the systems. Therefore, this strategy limits the influence of the slowest system, in our case, the electric one, during the braking process while maximizing battery regeneration.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
UMA Racing Team: Una experiencia en participación en competiciones universitarias.
En este trabajo se presenta la experiencia del equipo UMA Racing Team de la Universidad de Málaga en la competición Motostudent. Esta competición consiste en el diseño de una motocicleta de competición por parte de estudiantes universitarios. No sólo se diseña y fabrica la motocicleta, sino que también se debe desarrollar un proyecto industrial para la comercialización de la misma. El proyecto desarrollado es evaluado bajo el punto de vista técnico, económico y también estético por un tribunal externo conformado por expertos del sector. Además, los prototipos son también evaluados en pruebas dinámicas y en una carrera. El equipo UMA Racing Team ha participado en cinco ediciones de esta competición con resultados destacables. Para los alumnos representa una oportunidad de trabajar en un proyecto real con plazos y presupuesto limitado y de exponer el resultado de su trabajo a profesionales que poseen un amplio conocimiento del sector. La interacción entre los estudiantes, las empresas y los profesionales contribuyen a que los participantes alcancen nuevas capacidades y habilidades muy valoradas por las empresas. La experiencia confirma que la incorporación al mercado laboral de los integrantes ha sido muy satisfactoria
Localization of gravity on a de Sitter thick braneworld without scalar fields
In this work we present a simple thick braneworld model that is generated by
an intriguing interplay between a 5D cosmological constant with a de Sitter
metric induced in the 3-brane without the inclusion of scalar fields. We show
that 4D gravity is localized on this brane, provide analytic expressions for
the massive Kaluza-Klein (KK) fluctuation modes and also show that the spectrum
of metric excitations displays a mass gap. We finally present the corrections
to Newton's law due to these massive modes. This model has no naked
singularities along the fifth dimension despite the existence of a mass gap in
the graviton spectrum as it happens in thick branes with 4D Poincare symmetry,
providing a simple model with very good features: the curvature is completely
smooth along the fifth dimension, it localizes 4D gravity and the spectrum of
gravity fluctuations presents a mass gap, a fact that rules out the existence
of phenomenologically dangerous ultralight KK excitations in the model. We
finally present our solution as a limit of scalar thick branes.Comment: 11 pages in latex, no figures, title and abstract changed, a new
section and some references adde
Estudio del Efecto de Hidrocoloides en el Control de la Actividad Acuosa en Gomitas Funcionales.
La tendencia actual es desarrollar alimentos funcionales en especial golosinas para la población infantil, puesto que estas contienen una alta concentración de azucares, sin proporcionar nutrientes que pudieran ser fundamentales para su correcto desarrollo. El objetivo fue desarrollar una gomita funcional a base de nopal y betabel con una actividad de agua (aw) que permita obtener una vida de anaquel aceptable. Se utilizaron hidrocoloides como goma guar, pectina y goma arábiga, los resultados muestran que la pectina presenta una mayor aw (0.893), comparada con la goma guar (0.853), el uso de goma guar y nopal incrementa la aw (0.926), comparada con el uso de betabel (0.901), debido a que el mucilago de nopal y la fibra insoluble disminuye las interacciones tipo gel, este fenómeno también se observa con el uso de betabel. Con un tiempo de almacenamiento de 8 días se observa que las formulaciones que contienen goma guar la aw va disminuyendo a pasar a valores de 0.867 (nopal) y 0.846 (betabel), para las formulaciones que contiene goma arábiga los valores incrementan de 0.839 a 0.857 (nopal) y 0.863 a 0.887 (betabel). Los resultados demuestran que el mejor hidrocolide para este sistema es la goma guar
q-Form fields on p-branes
In this paper, we give one general method for localizing any form (q-form)
field on p-branes with one extra dimension, and apply it to some typical
p-brane models. It is found that, for the thin and thick Minkowski branes with
an infinite extra dimension, the zero mode of the q-form fields with q<(p-1)/2
can be localized on the branes. For the thick Minkowski p-branes with one
finite extra dimension, the localizable q-form fields are those with q<p/2, and
there are also some massive bound Kaluza-Klein modes for these q-form fields on
the branes. For the same q-form field, the number of the bound Kaluza-Klein
modes (but except the scalar field (q=0)) increases with the dimension of the
p-branes. Moreover, on the same p-brane, the q-form fields with higher q have
less number of massive bound KK modes. While for a family of pure geometrical
thick p-branes with a compact extra dimension, the q-form fields with q<p/2
always have a localized zero mode. For a special pure geometrical thick
p-brane, there also exist some massive bound KK modes of the q-form fields with
q<p/2, whose number increases with the dimension of the p-brane.Comment: 14 pages, 2 figures, published versio
Nitrogen and Phosphorous Retention in Tropical Eutrophic Reservoirs with Water Level Fluctuations: A Case Study Using Mass Balances on a Long-Term Series
Nitrogen and phosphorous loading drives eutrophication of aquatic systems. Lakes and reservoirs are often effective N and P sinks, but the variability of their biogeochemical dynamics is still poorly documented, particularly in tropical systems. To contribute to the extending of information on tropical reservoirs and to increase the insight on the factors affecting N and P cycling in aquatic ecosystems, we here report on a long-term N and P mass balance (2003–2018) in Valle de Bravo, Mexico, which showed that this tropical eutrophic reservoir lake acts as a net sink of N (−41.7 g N m y) and P (−2.7 g P m y), mainly occurring through net sedimentation, equivalent to 181% and 68% of their respective loading (23.0 g N m y and 4.2 g P m y). The N mass balance also showed that the Valle de Bravo reservoir has a high net N atmospheric influx (31.6 g N m y), which was 1.3 times the external load and likely dominated by N fixation. P flux was driven mainly by external load, while in the case of N, net fixation also contributed. During a period of high water level fluctuations, the net N atmospheric flux decreased by 50% compared to high level years. Our results outlining water regulation can be used as a useful management tool of water bodies, by decreasing anoxic conditions and net atmospheric fluxes, either through decreasing nitrogen fixation and/or promoting denitrification and other microbial processes that alleviate the N load. These findings also sustain the usefulness of long-term mass balances to assess biogeochemical dynamics and its variability.This research was funded by UNAM, PAPIIT-IN207702 and CONACYT-SEMARNAT, C01-1125 projects to M.M-
Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC
The uncertainty on the calorimeter energy response to jets of particles is
derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the
calorimeter response to single isolated charged hadrons is measured and
compared to the Monte Carlo simulation using proton-proton collisions at
centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009
and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter
response to specific types of particles (positively and negatively charged
pions, protons, and anti-protons) is measured and compared to the Monte Carlo
predictions. Finally, the jet energy scale uncertainty is determined by
propagating the response uncertainty for single charged and neutral particles
to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3%
for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table,
submitted to European Physical Journal
Measurement of the cross-section and charge asymmetry of bosons produced in proton-proton collisions at TeV with the ATLAS detector
This paper presents measurements of the and cross-sections and the associated charge asymmetry as a
function of the absolute pseudorapidity of the decay muon. The data were
collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with
the ATLAS experiment at the LHC and correspond to a total integrated luminosity
of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements
varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the
1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured
with an uncertainty between 0.002 and 0.003. The results are compared with
predictions based on next-to-next-to-leading-order calculations with various
parton distribution functions and have the sensitivity to discriminate between
them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables,
submitted to EPJC. All figures including auxiliary figures are available at
https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13
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