1,632 research outputs found
Intermediate‐Depth Earthquakes Controlled by Incoming Plate Hydration Along Bending‐Related Faults
Intermediate‐depth earthquakes (focal depths 70–300 km) are enigmatic with respect to their nucleation and rupture mechanism and the properties controlling their spatial distribution. Several recent studies have shown a link between intermediate‐depth earthquakes and the thermal‐petrological path of subducting slabs in relation to the stability field of hydrous minerals. Here we investigate whether the structural characteristics of incoming plates can be correlated with the intermediate‐depth seismicity rate. We quantify the structural characteristics of 17 incoming plates by estimating the maximum fault throw of bending‐related faults. Maximum fault throw exhibits a statistically significant correlation with the seismicity rate. We suggest that the correlation between fault throw and intermediate‐depth seismicity rate indicates the role of hydration of the incoming plate, with larger faults reflecting increased damage, greater fluid circulation, and thus more extensive slab hydration
Mapping and modelling the geographical distribution and environmental limits of podoconiosis in Ethiopia
BACKGROUND
Ethiopia is assumed to have the highest burden of podoconiosis globally, but the geographical distribution and environmental limits and correlates are yet to be fully investigated. In this paper we use data from a nationwide survey to address these issues.
METHODOLOGY
Our analyses are based on data arising from the integrated mapping of podoconiosis and lymphatic filariasis (LF) conducted in 2013, supplemented by data from an earlier mapping of LF in western Ethiopia in 2008-2010. The integrated mapping used woreda (district) health offices' reports of podoconiosis and LF to guide selection of survey sites. A suite of environmental and climatic data and boosted regression tree (BRT) modelling was used to investigate environmental limits and predict the probability of podoconiosis occurrence.
PRINCIPAL FINDINGS
Data were available for 141,238 individuals from 1,442 communities in 775 districts from all nine regional states and two city administrations of Ethiopia. In 41.9% of surveyed districts no cases of podoconiosis were identified, with all districts in Affar, Dire Dawa, Somali and Gambella regional states lacking the disease. The disease was most common, with lymphoedema positivity rate exceeding 5%, in the central highlands of Ethiopia, in Amhara, Oromia and Southern Nations, Nationalities and Peoples regional states. BRT modelling indicated that the probability of podoconiosis occurrence increased with increasing altitude, precipitation and silt fraction of soil and decreased with population density and clay content. Based on the BRT model, we estimate that in 2010, 34.9 (95% confidence interval [CI]: 20.2-51.7) million people (i.e. 43.8%; 95% CI: 25.3-64.8% of Ethiopia's national population) lived in areas environmentally suitable for the occurrence of podoconiosis.
CONCLUSIONS
Podoconiosis is more widespread in Ethiopia than previously estimated, but occurs in distinct geographical regions that are tied to identifiable environmental factors. The resultant maps can be used to guide programme planning and implementation and estimate disease burden in Ethiopia. This work provides a framework with which the geographical limits of podoconiosis could be delineated at a continental scale
In vivo detection of activated platelets allows characterizing rupture of atherosclerotic plaques with molecular magnetic resonance imaging in mice
BACKGROUND: Early and non-invasive detection of platelets on micro atherothrombosis provides a means to identify unstable plaque and thereby allowing prophylactic treatment towards prevention of stroke or myocardial infarction. Molecular magnetic resonance imaging (mMRI) of activated platelets as early markers of plaque rupture using targeted contrast agents is a promising strategy. In this study, we aim to specifically image activated platelets in murine atherothrombosis by in vivo mMRI, using a dedicated animal model of plaque rupture. METHODS: An antibody targeting ligand-induced binding sites (LIBS) on the glycoprotein IIb/IIIa-receptor of activated platelets was conjugated to microparticles of iron oxide (MPIO) to form the LIBS-MPIO contrast agent causing a signal-extinction in T2*-weighted MRI. ApoE(-/-) mice (60 weeks-old) were fed a high fat diet for 5 weeks. Using a small needle, the surface of their carotid plaques was scratched under blood flow to induce atherothrombosis. In vivo 9.4 Tesla MRI was performed before and repetitively after intravenous injection of either LIBS-MPIO versus non-targeted-MPIO. RESULTS: LIBS-MPIO injected animals showed a significant signal extinction (p/= 2% of the vascular lumen. Histology further confirmed significant binding of LIBS-MPIO compared to control-MPIO on the thrombus developing on the surface of ruptured plaques (p<0.01). CONCLUSION: in vivo mMRI detected activated platelets on mechanically ruptured atherosclerotic plaques in ApoE(-/-) mice with a high sensititvity. This imaging technology represents a unique opportunity for noninvasive detection of atherothrombosis and the identification of unstable atherosclerotic plaques with the ultimate promise to prevent strokes and myocardial infarctions
Avaliação econômica das anticitocinas adalimumabe, etanercepte e infliximabe no tratamento da artrite reumatoide no Estado do Paraná
Este estudo objetivou realizar uma avaliação econômica das anticitocinas adalimumabe (ADA), etanercepte (ETA) e infliximabe (IFX) para o tratamento da artrite reumatoide no Estado do Paraná, sob a perspectiva do SUS. Os dados de eficácia e segurança dos tratamentos foram buscados na literatura, e os custos foram calculados com valores gastos pelo SUS para cada um dos tratamentos. Foi elaborado o modelo de Markov para obter a relação custo-efetividade de cada tratamento. A relação custo-efetividade incremental (ICER) comparado ao tratamento padrão também foi calculada para cada anticitocina. Análises de sensibilidade e taxas de desconto foram aplicadas. Na avaliação custo-efetividade, encontraram-se custos por QALY de R 437.486,00 e R 628.124,00, R 965.927,00 para ADA, ETA e IFX, respectivamente. Nas análises de sensibilidade, o ETA e o ADA apresentaram valores próximos. Cabe aos gestores públicos e aos médicos prescritores a escolha adequada para cada paciente, entre os tratamentos disponibilizados.This study aimed to perform an economic evaluation of anticytokines adalimumab (ADA), etanercept (ETA) and infliximab (IFX) for the treatment of rheumatoid arthritis in the State of Parana, in Brazil, in the perspective of the Brazilian Unified Health System. Data on efficacy and safety of treatment were collected in literature, and costs were calculated on the amounts spent by the Government for each treatment. A Markov model was performed to get the cost-effectiveness of each treatment. The incremental cost-effectiveness relationship (ICER) compared to a standard treatment was also calculated for each anticytokine. Sensitivity analysis and discount rates were applied. In assessing cost-effectiveness we found the following values (cost at R per QALY) was 628,124.00, 509,974.00 and 965,927.00 (for ADA, ETA and IFX). In the sensitivity analysis, ETA and ADA showed similar values. It is for public managers and physicians the choice for each patient, among the treatments available
Hiding from the Moonlight: Luminosity and Temperature Affect Activity of Asian Nocturnal Primates in a Highly Seasonal Forest
The effect of moonlight and temperature on activity of slow lorises was previously little known and this knowledge might be useful for understanding many aspects of their behavioural ecology, and developing strategies to monitor and protect populations. In this study we aimed to determine if the activity of the pygmy loris (Nycticebus pygmaeus) is affected by ambient temperature and/or moonlight in a mixed deciduous forest. We radio-collared five females and five males in the Seima Protection Forest, Cambodia, in February to May, 2008 and January to March, 2009 and recorded their behaviour at 5 minutes intervals, totalling 2736 observations. We classified each observation as either inactive (sleeping or alert) or active behaviour (travel, feeding, grooming, or others). Moon luminosity (bright/dark) and ambient temperature were recorded for each observation. The response variable, activity, was binary (active or inactive), and a logit link function was used. Ambient temperature alone did not significantly affect mean activity. Although mean activity was significantly affected by moonlight, the interaction between moonlight and temperature was also significant: on bright nights, studied animals were increasingly more active with higher temperature; and on dark nights they were consistently active regardless of temperature. The most plausible explanation is that on bright cold nights the combined risk of being seen and attacked by predators and heat loss outweigh the benefit of active behaviours
Ultrashort filaments of light in weakly-ionized, optically-transparent media
Modern laser sources nowadays deliver ultrashort light pulses reaching few
cycles in duration, high energies beyond the Joule level and peak powers
exceeding several terawatt (TW). When such pulses propagate through
optically-transparent media, they first self-focus in space and grow in
intensity, until they generate a tenuous plasma by photo-ionization. For free
electron densities and beam intensities below their breakdown limits, these
pulses evolve as self-guided objects, resulting from successive equilibria
between the Kerr focusing process, the chromatic dispersion of the medium, and
the defocusing action of the electron plasma. Discovered one decade ago, this
self-channeling mechanism reveals a new physics, widely extending the frontiers
of nonlinear optics. Implications include long-distance propagation of TW beams
in the atmosphere, supercontinuum emission, pulse shortening as well as
high-order harmonic generation. This review presents the landmarks of the
10-odd-year progress in this field. Particular emphasis is laid to the
theoretical modeling of the propagation equations, whose physical ingredients
are discussed from numerical simulations. Differences between femtosecond
pulses propagating in gaseous or condensed materials are underlined. Attention
is also paid to the multifilamentation instability of broad, powerful beams,
breaking up the energy distribution into small-scale cells along the optical
path. The robustness of the resulting filaments in adverse weathers, their
large conical emission exploited for multipollutant remote sensing, nonlinear
spectroscopy, and the possibility to guide electric discharges in air are
finally addressed on the basis of experimental results.Comment: 50 pages, 38 figure
Decay of the High-K Isomeric State to a Rotational Band in 257Rf
The 257Rf isotope has been populated via the 208Pb(50Ti, n) fusion-evaporation reaction and delayed gamma-ray and electron decay spectroscopy has been performed. The existence of a high-K isomeric state in 257Rf has been confirmed. The isomeric state decays into a rotational band based on the 11/2(-)[725] excitation, which was observed up to spin of (23/2(-)). Three multipolarity-E1 gamma transitions depopulating the isomeric state have been observed, which fixes the spin for that state to (21/2(+)). This assignment agrees with theoretical predictions calculated with the microscopic-macroscopic approach, which suggest the isomeric state to be formed by coupling an unpaired 11/2(-)[725] quasineutron to the (1/2(-)[521] circle times 9/2(+)[624])(5)- two-quasiproton state. The same two-quasiproton excitation is possible for the lowest isomer in 256Rf
Disturbance and stress - different meanings in ecological dynamics?
There is an increasing frequency of papers
addressing disturbance and stress in ecology without
clear delimitation of their meaning. Some authors
use the terms disturbance and stress exclusively as
impacts, while others use them for the entire process,
including both causes and effects. In some studies, the
disturbance is considered as a result of a temporary
impact, which is positive for the ecosystem, while
stress is a negative, debilitating impact. By developing
and testing simple theoretical models, the authors
propose to differentiate disturbance and stress by
frequency. If the frequency of the event enables the
variable to reach a dynamic equilibrium which might
be exhibited without this event, then the event (plus its
responses) is a disturbance for the system. If frequency
prevents the variable’s return to similar pre-event
dynamics and drives or shifts it to a new trajectory,
then we are facing stress. The authors propose that
changes triggered by the given stimuli can be evaluated
on an absolute scale, therefore, direction of change of the variable must not be used to choose one
term or the other, i.e. to choose between stress and
disturbance
Coulomb excitation of neutron-rich Na nuclei with MINIBALL at REX-ISOLDE: Mapping the borders of the island of inversion
Phylogenomics Reshuffles the Eukaryotic Supergroups
Background. Resolving the phylogenetic relationships between eukaryotes is an ongoing challenge of evolutionary biology. In recent years, the accumulation of molecular data led to a new evolutionary understanding, in which all eukaryotic diversity has been classified into five or six supergroups. Yet, the composition of these large assemblages and their relationships remain controversial. Methodology/Principle Findings. Here, we report the sequencing of expressed sequence tags (ESTs) for two species belonging to the supergroup Rhizaria and present the analysis of a unique dataset combining 29908 amino acid positions and an extensive taxa sampling made of 49 mainly unicellular species representative of all supergroups. Our results show a very robust relationship between Rhizaria and two main clades of the supergroup chromalveolates: stramenopiles and alveolates. We confirm the existence of consistent affinities between assemblages that were thought to belong to different supergroups of eukaryotes, thus not sharing a close evolutionary history. Conclusions. This well supported phylogeny has important consequences for our understanding of the evolutionary history of eukaryotes. In particular, it questions a single red algal origin of the chlorophyll-c containing plastids among the chromalveolates. We propose the abbreviated name ‘SAR’ (Stramenopiles+Alveolates+Rhizaria) to accommodate this new super assemblage of eukaryotes, which comprises the largest diversity of unicellular eukaryotes
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