3,622 research outputs found
Experiences Developing Safe and Fault-Tolerant Tele-Operated Service Robots. A Case Study in Shipyards
Human operators use tele-operated service robots for performing more or less hazardous
operations (manipulation of heavy and/or dangerous products) in more or less hostile
environments (nuclear reactors, space missions, warehouses, etc). Anyway, independently
of the operation, the robot has to interact with both the environment it is working on and
with human operators. Therefore, it is essential that the design (which include both software
and hardware) of the robot involves no risk, or at least an acceptable level of risk, neither for
the operators, nor for the environment nor for the robot itself.
Nevertheless, it is not always possible to make a system free of failures in its design or
operation. Apart from the risk inherent to the use of the mechanisms themselves, these
systems work in hazardous environments, where the probability of the risk is higher than
normal. Should a failure happen, its consequences could even involve the loss of human
lives. (Neumann, 1994) documents many cases of computer-related failures, such as the
Therac-25 (a radiation-therapy device), the missiles shield in Saudi Arabia, etc.
Nevertheless, safety aspects are seldom included in the early phases of the system design
process from the beginning, even though they are a critic aspect. Generally, safety has to
conform and adapt to the already designed system and not vice versa, when it is widely
known that safety involves not only the design of the software but also the hardware. Even
more, a simple hardware solution can eliminate a hazard or simplify the software design in
many situations.This research has been funded by the Spanish CICYT project MEDWSA (TIN2006-15175-
C05-02) and the Regional Government of Murcia SĂ©neca Program (02998-PI-05)
Child Head Circumference and Placental MFSD2a Expression Are Associated to the Level of MFSD2a in Maternal Blood During Pregnancy
Gestational diabetes mellitus (GDM) is a world-wide health challenge, which prevalence is expected to increase in parallel to the epidemic of obesity. Children born from GDM mothers have lower levels of docosahexaenoic acid (DHA) in cord blood, which might influence their neurodevelopment. Recently, the membrane transporter Major Family Super Domain 2a (MFSD2a) was associated with the selective transportation of DHA as lysophospholipids. The expression of the DHA membrane transporter MFSD2a is lower in GDM placentas, which could affect materno-fetal DHA transport. Humans with homozygous inactivating mutations in the MFSD2a gene present severe microcephaly and intellectual impairments. Herein, we intended to identify early blood biomarkers that may be of use during pregnancy to monitor the offspring development and the adequate nutritional interventions, such as nutritional supplementation, that may be selected to improve it. We evaluated MFSD2a expression in maternal blood at the third trimester of pregnancy, and its potential relationship with the expression of placental MFSD2a at delivery and child outcomes. Three groups of pregnant women were recruited: 25 controls, 23 GDM with dietary treatment, and 20 GDM with insulin treatment. Maternal and neonatal anthropometric and biochemical parameters were evaluated. MFSD2a was analyzed in placenta, blood and serum. MFSD2a protein expression in maternal blood was significantly lower in GDM groups and correlated with placental MFSD2a and Z-score neonatal head circumference during the first 6 months of life. The cord/maternal serum ratio of DHA, a solid indicator of materno-fetal DHA transport, was reduced in GDM groups and correlated with MFSD2a in maternal blood at the third trimester and in placenta at delivery. This indicates that altered MFSD2a levels in maternal blood during pregnancy might influence placental nutrient transport and fetal neurodevelopment. Furthermore, MFSD2a levels in maternal blood on the third trimester were inversely correlated to DHA in maternal serum lyso-PL. Thus, the level of MFSD2a in maternal blood could be used as a potential biomarker for the early detection of disturbances of MFSD2a expression during pregnancy and the subsequent consequences for the neurodevelopment of the child, as well as it may help to choose the optimal treatment approach for the affected subjects
Robustness of Cooperation in the Evolutionary Prisoner's Dilemma on Complex Networks
Recent studies on the evolutionary dynamics of the Prisoner's Dilemma game in
scale-free networks have demonstrated that the heterogeneity of the network
interconnections enhances the evolutionary success of cooperation. In this
paper we address the issue of how the characterization of the asymptotic states
of the evolutionary dynamics depends on the initial concentration of
cooperators. We find that the measure and the connectedness properties of the
set of nodes where cooperation reaches fixation is largely independent of
initial conditions, in contrast with the behavior of both the set of nodes
where defection is fixed, and the fluctuating nodes. We also check for the
robustness of these results when varying the degree heterogeneity along a
one-parametric family of networks interpolating between the class of
Erdos-Renyi graphs and the Barabasi-Albert networks.Comment: 18 pages, 6 figures, revised version accepted for publication in New
Journal of Physics (2007
Tritordeum breads are well tolerated with preference over gluten-free breads in non-celiac wheat-sensitive patients and its consumption induce changes in gut bacteria
BACKGROUND
The ingestion of wheat and other cereals are related to several gut disorders. The specific components responsible for non-celiac wheat-sensitivity (NCWS) may include gluten and other compounds. Tritordeum is a new cereal derived from crossing durum wheat with a wild barley species, which differs from bread wheat in its gluten composition. In the present work, we examined the response of NCWS patients to tritordeum bread Gastrointestinal symptoms as well as tritordeum acceptability, gluten immunogenic peptides excretion, and the composition and structure of the intestinal microbiota were evaluated.
RESULTS
Gastrointestinal symptoms of the subjects showed no significant change between the gluten-free bread and the tritordeum bread. Participating subjects rated tritordeum bread higher than the gluten-free bread. Analysis of the bacterial gut microbiota indicated that tritordeum consumption does not alter the global structure and composition of the intestinal microbiota, and only a few changes in some butyrate-producing bacteria were observed.
CONCLUSIONS
All the results derived from acceptability, biochemical and microbiological tests suggest that tritordeum may be tolerated by a sub-set of NCWS sufferers who do not require strict exclusion of gluten from their diet. (c) 2020 Society of Chemical Industry
RecuperaciĂłn espontánea despuĂ©s de interrumpir las maniobras de resucitaciĂłn tras parada cardĂaca. A propĂłsito de un caso
Semi-Automatic identification and pre-screening of geological–geotechnical deformational processes using persistent scatterer interferometry datasets
Highlights from the Pierre Auger Observatory
The Pierre Auger Observatory is the world's largest cosmic ray observatory.
Our current exposure reaches nearly 40,000 km str and provides us with an
unprecedented quality data set. The performance and stability of the detectors
and their enhancements are described. Data analyses have led to a number of
major breakthroughs. Among these we discuss the energy spectrum and the
searches for large-scale anisotropies. We present analyses of our X
data and show how it can be interpreted in terms of mass composition. We also
describe some new analyses that extract mass sensitive parameters from the 100%
duty cycle SD data. A coherent interpretation of all these recent results opens
new directions. The consequences regarding the cosmic ray composition and the
properties of UHECR sources are briefly discussed.Comment: 9 pages, 12 figures, talk given at the 33rd International Cosmic Ray
Conference, Rio de Janeiro 201
A search for point sources of EeV photons
Measurements of air showers made using the hybrid technique developed with
the fluorescence and surface detectors of the Pierre Auger Observatory allow a
sensitive search for point sources of EeV photons anywhere in the exposed sky.
A multivariate analysis reduces the background of hadronic cosmic rays. The
search is sensitive to a declination band from -85{\deg} to +20{\deg}, in an
energy range from 10^17.3 eV to 10^18.5 eV. No photon point source has been
detected. An upper limit on the photon flux has been derived for every
direction. The mean value of the energy flux limit that results from this,
assuming a photon spectral index of -2, is 0.06 eV cm^-2 s^-1, and no celestial
direction exceeds 0.25 eV cm^-2 s^-1. These upper limits constrain scenarios in
which EeV cosmic ray protons are emitted by non-transient sources in the
Galaxy.Comment: 28 pages, 10 figures, accepted for publication in The Astrophysical
Journa
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