3,838 research outputs found
Quantitative assessment of diffuse myocardial fibrosis in II-type diabetes mellitus patients using T1 mapping technique: preliminary data
In diabetic cardiomyopathy (DCM), ventricular remodelling consists in a progressive impairment of myocardial contraction (evolving from diastolic to combined diastolic-systolic dysfunction) occurring regardless of ischemic heart disease, hypertension or other macrovascular complications, which ultimately leads to heart failure. Early stages of DCM are asymptomatic and characterised by initial contractile disfunction and various degree of myocardial fibrosis, that may not be recognised by traditional cardiology tests. Our purpose was to detect myocardial fibrotic infiltration in DM-II patients by using T1-mapping technique with extracellular volume fraction (ECV) measurement
A Model For Late Dark Matter Decay
The standard cold dark matter cosmological model, while successful in
explaining the observed large scale structure of the Universe, tends to
overpredict structure on small scales. It has been proposed this problem may be
alleviated in a class of late-decaying dark matter models, in which the parent
dark matter particle decays to an almost degenerate daughter, plus a
relativistic final state. We construct explicit particle physics models that
realize this goal while obeying observational constraints. To achieve this, we
introduce a pair of fermionic dark matter candidates and a new scalar field,
which obey either a Z4 or a U(1) symmetry. Through the spontaneous breaking of
these symmetries, and coupling of the new fields to standard model particles,
we demonstrate that the desired decay process may be obtained. We also discuss
the dark matter production processes in these models.Comment: 10 pages, 8 figures; updated to match published version, minor
changes to text and figure
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Simulating movement devices used in hospital evacuation
In hospitals, the evacuation of those with severe movement impairments can be highly problematic for the patients, for the staff and for other evacuees. It is critical to understand the performance of horizontal and vertical evacuation procedures, including the means by which people with reduced mobility can be assisted during stair descent. Microsimulation modelling provides a useful tool to assess evacuation strategies, given the challenges of preparing and transporting patients in need of on-going care and the unfeasibility of real evacuation drills. However, current simulation models typically focus on the movement of individual agents, not the staff-patient interactions and sizable equipment required to carry out assisted evacuation. To address this, the buildingEXODUS evacuation model has been enhanced to represent moving objects in addition to moving individual agents. This paper describes the modelling theory behind this development, where dedicated data has been applied to enable the explicit specification of evacuation devices, operated by agents (for instance, representing the vertical travel speeds achieved—with averages ranging between 0.6 m/s and 0.84 m/s—when employing different movement devices). Algorithms are presented that calculate the movement of devices along corridors, through doorways and in stairway descent, including a method of geometric decomposition of the available hospital evacuation routes. This new functionality addresses the key evacuation components of repeated patient collection and has numerous applications, both in simulating hospital evacuation and in representing evacuation of other premises that include people with reduced mobility. Examination of the performance of this functionality found it predicated performance within 6% of expectation. Once further testing is completed, the resultant tool can be used to significantly enhance planning and diagnostic capabilities related to the evacuation of hospital and other healthcare facilities
A roadmap to integrate astrocytes into Systems Neuroscience
Systems Neuroscience is still mainly a neuronal field, despite the plethora of evidence supporting the fact that astrocytes modulate local neural circuits, networks, and complex behaviors. In this article, we sought to identify which types of studies are necessary to establish whether astrocytes, beyond their well-documented homeostatic and metabolic functions, perform computations implementing mathematical algorithms that sub-serve coding and higher-brain functions. First, we reviewed Systems-like studies that include astrocytes in order to identify computational operations that these cells may perform, using Ca transients as their encoding language. The analysis suggests that astrocytes may carry out canonical computations in time scales of sub-seconds to seconds in sensory processing, neuromodulation, brain state, memory formation, fear, and complex homeostatic reflexes. Next, we propose a list of actions to gain insight into the outstanding question of which variables are encoded by such computations. The application of statistical analyses based on machine learning, such as dimensionality reduction and decoding in the context of complex behaviors, combined with connectomics of astrocyte-neuronal circuits, are, in our view, fundamental undertakings. We also discuss technical and analytical approaches to study neuronal and astrocytic populations simultaneously, and the inclusion of astrocytes in advanced modeling of neural circuits, as well as in theories currently under exploration, such as predictive coding and energy-efficient coding. Clarifying the relationship between astrocytic Ca and brain coding may represent a leap forward towards novel approaches in the study of astrocytes in health and disease.Junior Leader Fellowhip Program by 'la Caixa' Banking Foundation, LCF/BQ/LI18/11630006
BFU2017-85936-P
BFU2016-75107-P
BFU2016-79735-P
FLAGERA-PCIN-2015-162-C02-02
HHMI 55008742
FPU13/05377
NIH R01NS099254
NSF 1604544
Agència de Gestio d’Ajuts Universitaris i de Recerca, 2017 SGR54
Increasing the simulation performance of large-scale evacuations using parallel computing techniques based on domain decomposition
Evacuation simulation has the potential to be used as part of a decision support system during large-scale incidents to provide advice to incident commanders. To be viable in these applications, it is essential that the simulation can run many times faster than real time. Parallel processing is a method of reducing run times for very large computational simulations by distributing the workload amongst a number of processors. This paper presents the development of a parallel version of the rule based evacuation simulation software buildingEXODUS using domain decomposition. Four Case Studies (CS) were tested using a cluster, consisting of 10 Intel Core 2 Duo (dual core) 3.16 GHz CPUs. CS-1 involved an idealised large geometry, with 20 exits, intended to illustrate the peak computational speed up performance of the parallel implementation, the population consisted of 100,000 agents; the peak computational speedup (PCS) was 14.6 and the peak real-time speedup (PRTS) was 4.0. CS-2 was a long area with a single exit area with a population of 100,000 agents; the PCS was 13.2 and the PRTS was 17.2. CS-3 was a 50 storey high rise building with a population of 8000/16,000 agents; the PCS was 2.48/4.49 and the PRTS was 17.9/12.9. CS-4 is a large realistic urban area with 60,000/120,000 agents; the PCS was 5.3/6.89 and the PRTS was 5.31/3.0. This type of computational performance opens evacuation simulation to a range of new innovative application areas such as real-time incident support, dynamic signage in smart buildings and virtual training environments
RORA and Posttraumatic Stress Trajectories: Main Effects and Interactions with Childhood Physical Abuse History.
BACKGROUND:
Longitudinal studies of posttraumatic stress (PTS) have documented environmental factors as predictors of trajectories of higher, versus lower, symptoms, among them experiences of childhood physical abuse. Although it is now well-accepted that genes and environments jointly shape the risk of PTS, no published studies have investigated genes, or gene-by-environment interactions (GxEs), as predictors of PTS trajectories. The purpose of this study was to fill this gap. METHODS AND MATERIALS:
We examined associations between variants of the retinoid-related orphan receptor alpha (RORA) gene and trajectory membership among a sample of predominantly non-Hispanic Black urban adults (N = 473). The RORA gene was selected based on its association with posttraumatic stress disorder (PTSD) in the first PTSD genome wide association study. Additionally, we explored GxEs between RORA variants and childhood physical abuse history. RESULTS:
We found that the minor allele of the RORA SNP rs893290 was a significant predictor of membership in a trajectory of consistently high PTS, relatively to a trajectory of consistently low PTS. Additionally, the GxE of rs893290 with childhood physical abuse was significant. Decomposition of the interaction showed that minor allele frequency was more strongly associated with membership in consistently high or decreasing PTS trajectories, relative to a consistently low PTS trajectory, among participants with higher levels of childhood physical abuse. CONCLUSION:
The results of the study provide preliminary evidence that variation in the RORA gene is associated with membership in trajectories of higher PTS and that these associations are stronger among persons exposed to childhood physical abuse. Replication and analysis of functional data are needed to further our understanding of how RORA relates to PTS trajectories
Allergic anaphylactic risk in farming activities: A systematic review
Allergic disorders in the agriculture sector are very common among farm workers, causing many injuries and occupational diseases every year. Agricultural employees are exposed to multiple conditions and various allergenic substances, which could be related to onset of anaphylactic reactions. This systematic review highlights the main clinical manifestation, the allergens that are mostly involved and the main activities that are usually involved. This research includes articles published on the major databases (PubMed, Cochrane Library, Scopus), using a combination of keywords. The online search yielded 489 references; after selection, by the authors, 36 articles (nine reviews and 27 original articles) were analyzed. From this analysis, the main clinical problems that were diagnosed in this category were respiratory (ranging from rhinitis to asthma) and dermatological (eczema, dermatitis, hives) in nature, with a wide symptomatology (from a simple local reaction to anaphylaxis). The main activities associated with these allergic conditions are harvesting or cultivation of fruit and cereals, beekeepers and people working in greenhouses. Finally, in addition to the allergens already known, new ones have emerged, including triticale, wine, spider and biological dust. For these reasons, in the agricultural sector, research needs to be amplified, considering new sectors, new technologies and new products, and ensuring a system of prevention to reduce this risk.peer-reviewe
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A methodology for collecting donning times of thermal protective immersion suits intended to be worn by passengers on vessels operating in cold environments
Adequate thermal protection for passengers travelling on-board vessels in cold climate regions, such as that provided by thermal protective immersion suits (TPIS), enhances passenger survivability in emergency situations, in particular those requiring the abandonment of the vessel. As emergency abandonment is a time critical process, it is essential to consider the time required to correctly don the TPIS. Testing standards, such as the International Maritime Organization guidelines, require that TPIS must be able to be donned within 2 minutes. Unfortunately, current practices quantifying donning times are questionable and so there is a limited evidence base that reliably quantifies donning times required by typical passengers. This paper presents a test procedure designed to reliably quantify the time required by test subjects to don the TPIS. Furthermore, the procedure assesses the donning correctness – a TPIS that is incorrectly donned is unlikely to offer appropriate thermal protection. The paper will also discuss the deficiencies in current practices to assess required donning time
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