252 research outputs found
COMPARACIÓN ENTRE PLUVIÓMETROS CUANTIFICA DIFERENCIAS EN EL MONITOREO DE LA PRECIPITACIÓN
Por décadas se ha trabajado para corregir las medidas de precipitación, sin embargo estos esfuerzos han sido escasos
en zonas tropicales montañosas. Cuatro pluviómetros de balancín (TB), con distinta resolución y comúnmente
utilizados en las montañas de los Andes, fueron comparados en este estudio: un DAVIS-RC-II, un HOBO-RG3-M, y
dos TE525MM (con y sin una pantalla Alter contra el viento). El desempeño de estos pluviómetros, instalados en el
Observatorio Ecohidrológico Zhurucay, sur del Ecuador, a 3780 m s.n.m., se evaluó en relación al sensor de mejor
resolución (0,1 mm), el TE525MM. El efecto de la intensidad de precipitación y condiciones del viento también se analizó
utilizando 2 años de datos. Los resultados revelan que (i) la precipitación medida por el TB de referencia es 5,6%
y 7,2% mayor que la de pluviómetros con resolución de 0,2 mm y 0.254 mm, respectivamente; (ii) la subestimación
de los sensores de menor resolución es mayor durante eventos de baja intensidad—una máxima diferencia de 11%
para intensidades 1 mm h1; (iii) intensidades menores a 2 mm h1, que ocurren el 75% del tiempo, no pueden ser
determinadas con exactitud para escalas menores a 30 minutos debido a la resolución de los pluviómetros, e.g. sesgo
absoluto > 10%; y (iv) el viento tiene un efecto similar en todos los sensores. Este análisis contribuye a mejorar la
exactitud y homogeneidad de las medidas de precipitación en los Andes mediante la cuantificación del rol clave de la
resolución de los pluviómetros.//Efforts to correct precipitation measurements have been ongoing for decades, but are scarce for tropical highlands.
Four tipping-bucket (TB) rain gauges with different resolution that are commonly used in the Andean mountain
region were compared-one DAVIS-RC-II, one HOBO-RG3-M, and two TE525MM TB gauges (with and without an
Alter-Type wind screen). The relative performance of these rain gauges, installed side-by-side in the Zhurucay Ecohydrological
Observatory, south Ecuador, at 3780 m a.s.l., was assessed using the TB with the highest resolution (0.1 mm)
as reference, i.e. the TE525MM. The effect of rain intensity and wind conditions on gauge performance was estimated
as well. Using 2 years of data, results reveal that (i) the precipitation amount for the reference TB is on average 5.6
to 7.2% higher than the rain gauges having a resolution of 0.2 mm and 0.254 mm respectively; (ii) relative underestimation
of precipitation from the gauges with coarser resolution is higher during low-intensity rainfall mounting to a
maximum deviation of 11% was observed for rain intensities 1 mm h1; (iii) precipitation intensities of 2 mm h1 or
less that occur 75% of the time cannot be determined accurately for timescales shorter than 30 minutes because of the
gauges’ resolution, e.g. the absolute bias is >10%; and (iv) wind has a similar effect on all sensors. This analysis contributes
to increase the accuracy and homogeneity of precipitation measurements throughout the Andean highlands,
by quantifying the key role of rain-gauge resolution
Inventory Existing Risk Scenarios
This report provides an inventory of existing hazard data, spatial data sets and socioeconomic projections to process scenario information and future risk projections for the ENHANCE case studies. As a basis for this inventory, we conducted a small survey across the EHNHANCE cases study on their data needs. Table 1.1 provides a preliminary overview of the hazard- and socioeconomic data and scenario's required within the different case studies. This overview on the case study data needs and the data availability within the different case study partners, was discussed during the project meetings in Venice, May 2013 and Ispra (September 2013).
During the meeting in Ispra, the case studies were offered a 2 days hands on workshop on how to use scenario and risk data or their case studies. This workshop was offered by IVM and JRC.
Since the ENHANCE project follows a risk based approach, we similarly have focused this report on (1) data and projections for different types of natural hazards (Chapter 2) and (2) trends in socioeconomic factors that influence exposure and vulnerability to the natural hazard (Chapter 3). In addition, we have specifically outlined methods to process socioeconomic scenarios (Chapter 4) and probabilistic methods (Chapter 5) to describe extreme events with a very low probability.
The main objectives of this report are to:
- Provide an inventory of dynamic hazard scenarios at the pan-European scale, based on existing information at JRC or other institutes;
- Provide an inventory of socioeconomic data and projections in Europe as well as some global outlook projections, possibly relevant for ENHANCE;
- Develop a probabilistic risk framework for identifying probabilities of extreme events in the case studies
Comparison of various models of Monte Carlo geant 4 code in simulations of prompt gamma production
In this paper, results of simulations of the gamma-ray production in reactions with 70 MeV protons in a target of PMMA are presented. The data obtained by means of two versions of Geant 4 software, 9.3 and 10.01, have shown significant differences in the gamma-ray spectra. The comparison between the calculated spectra and the measured ones has been carried out. The tested versions do not give satisfactory agreement with the experimental result. The reason of the performed verification was the planned application of this simulation toolkit for the preparation of in vivo dosimetry based on the prompt gamma-ray measurements for the proton therapy
Trends in heat and cold wave risks for the Italian Trentino-Alto Adige region from 1980 to 2018
Heat waves (HWs) and cold waves (CWs) can have considerable impact on
people. Mapping risks of extreme temperature at local scale, accounting for
the interactions between hazard, exposure, and vulnerability, remains a
challenging task. In this study, we quantify risks from HWs and CWs for the
Trentino-Alto Adige region of Italy from 1980 to 2018 at high spatial
resolution. We use the Heat Wave Magnitude Index daily (HWMId) and the Cold
Wave Magnitude Index daily (CWMId) as the hazard indicators. To obtain HWs
and CW risk maps we combined the following: (i) occurrence probability maps of the hazard
obtained using the zero-inflated Tweedie distribution (accounting directly
for the absence of events for certain years), (ii) normalized population
density maps, and (iii) normalized vulnerability maps based on eight
socioeconomic indicators. The methodology allowed us to disentangle the
contributions of each component of the risk relative to total change in
risk. We find a statistically significant increase in HW hazard and
exposure, while CW hazard remained stagnant in the analyzed area over the
study period. A decrease in vulnerability to extreme temperature spells is
observed through the region except in the larger cities where vulnerability
increased. HW risk increased in 40 % of the region, with the increase
being greatest in highly populated areas. Stagnant CW hazard and declining
vulnerability result in reduced CW risk levels overall, except for the four
main cities where increased vulnerability and exposure increased risk
levels. These findings can help to steer investments in local risk
mitigation, and this method can potentially be applied to other regions
where there are sufficient detailed data.</p
Muscle Fatigue Analysis Using OpenSim
In this research, attempts are made to conduct concrete muscle fatigue
analysis of arbitrary motions on OpenSim, a digital human modeling platform. A
plug-in is written on the base of a muscle fatigue model, which makes it
possible to calculate the decline of force-output capability of each muscle
along time. The plug-in is tested on a three-dimensional, 29 degree-of-freedom
human model. Motion data is obtained by motion capturing during an arbitrary
running at a speed of 3.96 m/s. Ten muscles are selected for concrete analysis.
As a result, the force-output capability of these muscles reduced to 60%-70%
after 10 minutes' running, on a general basis. Erector spinae, which loses
39.2% of its maximal capability, is found to be more fatigue-exposed than the
others. The influence of subject attributes (fatigability) is evaluated and
discussed
Recruitment, augmentation and apoptosis of rat osteoclasts in 1,25-(OH)2D3 response to short-term treatment with 1,25-dihydroxyvitamin D3in vivo
Background
Although much is known about the regulation of osteoclast (OC) formation and activity, little is known about OC senescence. In particular, the fate of of OC seen after 1,25-(OH)2D3 administration in vivo is unclear. There is evidence that the normal fate of OC is to undergo apoptosis (programmed cell death). We have investigated the effect of short-term application of high dose 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) on OC apoptosis in an experimental rat model.
Methods
OC recruitment, augmentation and apoptosis was visualised and quantitated by staining histochemically for tartrate resistant acid phosphatase (TRAP), double staining for TRAP/ED1 or TRAP/DAPI, in situ DNA fragmentation end labelling and histomorphometric analysis.
Results
Short-term treatment with high-dose 1,25-(OH)2D3 increased the recruitment of OC precursors in the bone marrow resulting in a short-lived increase in OC numbers. This was rapidly followed by an increase in the number of apoptotic OC and their subsequent removal. The response of OC to 1,25-(OH)2D3 treatment was dose and site dependent; higher doses producing stronger, more rapid responses and the response in the tibiae being consistently stronger and more rapid than in the vertebrae.
Conclusions
This study demonstrates that (1) after recruitment, OC are removed from the resorption site by apoptosis (2) the combined use of TRAP and ED1 can be used to identify OC and their precursors in vivo (3) double staining for TRAP and DAPI or in situ DNA fragmentation end labelling can be used to identify apoptotic OC in vivo
Multisectoral partnerships and risk information
Knowing the increasing trends in natural disasters and losses, it is imperative to take action on disaster risks to improve resilience of European societies to natural hazards. The main goal, therefore, of the ENHANCE project is to develop and analyse innovative ways to manage natural hazard risks. The key is to develop new multi-sectoral partnerships (MSPs) that aim at reducing or redistributing risk, and increase resilience of societiesinfo:eu-repo/semantics/publishedVersio
Emergent vulnerability to climate-driven disturbances in European forests
Forest disturbance regimes are expected to intensify as Earth's climate changes. Quantifying forest vulnerability to disturbances and understanding the underlying mechanisms is crucial to develop mitigation and adaptation strategies. However, observational evidence is largely missing at regional to continental scales. Here, we quantify the vulnerability of European forests to fires, windthrows and insect outbreaks during the period 1979-2018 by integrating machine learning with disturbance data and satellite products. We show that about 33.4 billion tonnes of forest biomass could be seriously affected by these disturbances, with higher relative losses when exposed to windthrows (40%) and fires (34%) compared to insect outbreaks (26%). The spatial pattern in vulnerability is strongly controlled by the interplay between forest characteristics and background climate. Hotspot regions for vulnerability are located at the borders of the climate envelope, in both southern and northern Europe. There is a clear trend in overall forest vulnerability that is driven by a warming-induced reduction in plant defence mechanisms to insect outbreaks, especially at high latitudes. Natural disturbances imperil healthy and productive forests, but quantifying their effects at large scales is challenging. Here the authors apply machine learning to disturbance records and satellite data to quantify and map European forest vulnerability to fires, windthrows, and insect outbreaks through 1979-2018.Peer reviewe
African heritage sites threatened as sea-level rise accelerates
The African coast contains heritage sites of ‘Outstanding Universal Value’ that face increasing risk from anthropogenic climate change. Here, we generated a database of 213 natural and 71 cultural African heritage sites to assess exposure to coastal flooding and erosion under moderate (RCP 4.5) and high (RCP 8.5) greenhouse gas emission scenarios. Currently, 56 sites (20%) are at risk from a 1-in-100-year coastal extreme event, including the iconic ruins of Tipasa (Algeria) and the North Sinai Archaeological Sites Zone (Egypt). By 2050, the number of exposed sites is projected to more than triple, reaching almost 200 sites under high emissions. Emissions mitigation from RCP 8.5 to RCP 4.5 reduces the number of very highly exposed sites by 25%. These findings highlight the urgent need for increased climate change adaptation for heritage sites in Africa, including governance and management approaches, site-specific vulnerability assessments, exposure monitoring, and protection strategies
Uncertainty and Bias in Global to Regional Scale Assessments of Current and Future Coastal Flood Risk
This study provides a literature-based comparative assessment of uncertainties and biases in global to world-regional scale assessments of current and future coastal flood risks, considering mean and extreme sea-level hazards, the propagation of these into the floodplain, people and coastal assets exposed, and their vulnerability. Globally, by far the largest bias is introduced by not considering human adaptation, which can lead to an overestimation of coastal flood risk in 2100 by up to factor 1300. But even when considering adaptation, uncertainties in how coastal societies will adapt to sea-level rise dominate with a factor of up to 27 all other uncertainties. Other large uncertainties that have been quantified globally are associated with socio-economic development (factors 2.3–5.8), digital elevation data (factors 1.2–3.8), ice sheet models (factor 1.6–3.8) and greenhouse gas emissions (factors 1.6–2.1). Local uncertainties that stand out but have not been quantified globally, relate to depth-damage functions, defense failure mechanisms, surge and wave heights in areas affected by tropical cyclones (in particular for large return periods), as well as nearshore interactions between mean sea-levels, storm surges, tides and waves. Advancing the state-of-the-art requires analyzing and reporting more comprehensively on underlying uncertainties, including those in data, methods and adaptation scenarios. Epistemic uncertainties in digital elevation, coastal protection levels and depth-damage functions would be best reduced through open community-based efforts, in which many scholars work together in collecting and validating these data
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