The automatic contrail tracking algorithm (ACTA) – developed to automatically follow contrails as they age, drift and spread – enables the study of a large number of contrails and the evolution of ...contrail properties with time. In this paper we present a year's worth of tracked contrails, from August 2008 to July 2009 in order to derive statistically significant mean values. The tracking is performed using the 5 min rapid-scan mode of the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on board the Meteosat Second Generation (MSG) satellites. The detection is based on the high spatial resolution of the images provided by the Moderate Resolution Imaging Spectroradiometer on board the Terra satellite (Terra/MODIS), where a contrail detection algorithm (CDA) is applied. The results show the satellite-derived average lifetimes of contrails and contrail-cirrus along with the probability density function (PDF) of other geometric characteristics such as mean coverage, distribution and width. In combination with specifically developed algorithms (RRUMS; Rapid Retrieval of Upwelling irradiance from MSG/SEVIRI and COCS (Cirrus Optical properties derived from CALIOP and SEVIRI), explained below) it is possible to derive the radiative forcing (RF), energy forcing (EF), optical thickness (τ) and altitude of the tracked contrails. Mean values here retrieved are duration, 1 h; length, 130 km; width, 8 km; altitude, 11.7 km; optical thickness, 0.34. Radiative forcing and energy forcing are shown for land/water backgrounds in day/night situations.
A novel approach for the detection of cirrus clouds and the retrieval of optical thickness and top altitude based on the measurements of the Spinning Enhanced Visible and Infrared Imager (SEVIRI) ...aboard the geostationary Meteosat Second Generation (MSG) satellite is presented. Trained with 8 000 000 co-incident measurements of the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) aboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) mission the new "cirrus optical properties derived from CALIOP and SEVIRI algorithm during day and night" (COCS) algorithm utilizes a backpropagation neural network to provide accurate measurements of cirrus optical depth tau at lambda = 532 nm and top altitude z every 15 min covering almost one-third of the Earth's atmosphere. The retrieved values are validated with independent measurements of CALIOP and the optical thickness derived by an airborne high spectral resolution lidar.
The reactor antineutrino anomaly might be explained by the oscillation of reactor antineutrinos toward a sterile neutrino of eV mass. In order to explore this hypothesis, the STEREO experiment ...measures the antineutrino energy spectrum in six different detector cells covering baselines between 9 and 11 m from the compact core of the ILL research reactor. In this Letter, results from 66 days of reactor turned on and 138 days of reactor turned off are reported. A novel method to extract the antineutrino rates has been developed based on the distribution of the pulse shape discrimination parameter. The test of a new oscillation toward a sterile neutrino is performed by comparing ratios of cells, independent of absolute normalization and of the prediction of the reactor spectrum. The results are found to be compatible with the null oscillation hypothesis and the best fit of the reactor antineutrino anomaly is excluded at 97.5% C.L.
Autonomous agents (AA) will increasingly be deployed as teammates instead of tools. In many operational situations, flawless performance from AA cannot be guaranteed. This may lead to a breach in the ...human’s trust, which can compromise collaboration. This highlights the importance of thinking about how to deal with error and trust violations when designing AA. The aim of this study was to explore the influence of uncertainty communication and apology on the development of trust in a Human–Agent Team (HAT) when there is a trust violation. Two experimental studies following the same method were performed with (I) a civilian group and (II) a military group of participants. The online task environment resembled a house search in which the participant was accompanied and advised by an AA as their artificial team member. Halfway during the task, an incorrect advice evoked a trust violation.
Uncertainty communication
was manipulated within-subjects,
apology
between-subjects. Our results showed that (a) communicating uncertainty led to higher levels of trust in both studies, (b) an incorrect advice by the agent led to a less severe decline in trust when that advice included a measure of uncertainty, and (c) after a trust violation, trust recovered significantly more when the agent offered an apology. The two latter effects were only found in the civilian study. We conclude that tailored agent communication is a key factor in minimizing trust reduction in face of agent failure to maintain effective long-term relationships in HATs. The difference in findings between participant groups emphasizes the importance of considering the (organizational) culture when designing artificial team members.
In Flanders, up to 20% of the coarse natural aggregates in concrete mixtures for certain applications in road pavement construction may be replaced by high-grade recycled concrete aggregates (RCA). ...The RCA and resulting recycled aggregate concrete (RAC) have to comply with the high-grade criteria specified in the Flemish ‘Standard Tender Specifications 250 version 3.1’ and require extensive and time-consuming testing procedures, leading to reluctance in effectively prescribing and using recycled aggregates. The objective of this case study is therefore to draw up practical recommendations for the rapid identification of high-grade RCA. RCA from different sources are investigated and subsequently used in two concrete road pavement construction applications, namely linear elements and applications within the Flemish concrete construction class ‘BF’ (i.e. cycle paths, footpaths and agricultural roads). The experimental results indicate that the aggregate density along with the water content appears to be good predictors for the resistance to abrasion (i.e. the Los Angeles coefficient). The aggregate experiments also show that, in order to fulfill the aforementioned tender specifications criteria, it is important to demolish and store the source material in such a way that no contamination with non-concrete materials (such as ceramics) takes place, maintaining a high specific density. The experiments on RAC, on the other hand, show that an aggregate replacement rate of up to 40% of the coarse fraction has no detrimental effect on the mechanical and durability performance. When comparing the results of both aggregate and concrete experiments, they show that freeze–thaw resistance of the concrete aggregates has slight to no impact on the freeze–thaw resistance of the concrete.
.
The STEREO experiment measures the electron antineutrino spectrum emitted in a research reactor using the inverse beta decay reaction on H nuclei in a gadolinium loaded liquid scintillator. The ...detection is based on a signal coincidence of a prompt positron and a delayed neutron capture event. The simulated response of the neutron capture on gadolinium is crucial for the comparison with data, in particular in the case of the detection efficiency. Among all stable isotopes,
155
Gd and
157
Gd have the highest cross sections for thermal neutron capture. The excited nuclei after the neutron capture emit gamma rays with a total energy of about 8MeV. The complex level schemes of
156
Gd and
158
Gd are a challenge for the modeling and prediction of the deexcitation spectrum, especially for compact detectors where gamma rays can escape the active volume. With a new description of the Gd (n,
γ
) cascades obtained using the FIFRELIN code, the agreement between simulation and measurements with a neutron calibration source was significantly improved in the STEREO experiment. A database of ten millions of deexcitation cascades for each isotope has been generated and is now available for the user.
Immunomodulatory therapies in sepsis Kox, W J; Volk, T; Kox, S N ...
Intensive care medicine,
01/2000, Letnik:
26 Suppl 1, Številka:
1
Journal Article
Recenzirano
Despite advances in critical care medicine, mortality from sepsis in ICU patients remains high. In response to several infectious and non-infectious stimuli, monocytes/ macrophages release a number ...of mediators, including cytokines, involved in the proinflammatory response that underlies sepsis. The excessive release of these mediators results in the development of whole body inflammation, and plays an important role in the pathogenesis of sepsis and septic shock. In addition, patients with sepsis also undergo an anti-inflammatory phase (the compensatory anti-inflammatory response syndrome) and at times, a mixed response with both pro-and anti-inflammatory components (the mixed antagonistic response syndrome). The initial systemic hyperinflammation is caused by production of inflammatory cytokines, especially tumour necrosis factor-a (TNF-alpha), and also interleukin-1 (IL-1), IL-6, and interferon gamma, which act synergistically with TNF-alpha in inducing shock in animal models. However, clinical trials aimed at downregulating these mediators using antibodies against endotoxin, TNF-alpha, antagonists of IL-1 or platelet activating factor have proved to be uniformly disappointing. Not only have these agents been found to have no effect, but they may also increase mortality. One of the reasons for such failure may be the lack of precise immunological monitoring during the course of sepsis. We have recently demonstrated that sepsis shows a biphasic immunological pattern during the initial and later phase: the early hyperinflammatory phase is counterbalanced by an anti-inflammatory response which may lead to a hypoinflammatory state. The latter is associated with immunodeficiency that is characterised by monocytic deactivation, so-called immunoparalysis. Interferon gamma-1 b has an immunoregulatory effect in patients with immunoparalysis during the compensatory anti-inflammatory response syndrome, not only restoring levels of HLA-DR expression but also reestablishing the ability of monocytes to secrete cytokines such as TNF-alpha. By monitoring immune status in septic patients, targeted intervention may lead to more success in immunomodulation of sepsis.
Although overuse wrist injuries can have serious consequences, young athletes often do not immediately report their injury to a physician. This qualitative study aimed to identify symptoms and ...limitations related to overuse wrist injuries that young athletes consider important and to compare those with sports physicians' opinions, in order to improve the diagnostic process for early identification of overuse wrist injuries.
Twenty-one athletes aged 13-25 years in wrist-loading sports (gymnastics, tennis, judo, field hockey, volleyball and rowing) with a (previous) overuse wrist injury were included. In five focus groups, participants discussed important signals and limitations of their injury, as well as a list of relevant items previously composed by sports physicians. Data were grouped into themes and (sub)categories and subsequently coded.
Of the resulting 224 signals and 80 limitations, respectively 81 and 20 were labelled important. Athletes considered both pain and limitations during daily life activities important indicators of overuse wrist injury, as well as long pain duration, acute onset of pain, and accompanying symptoms like swelling, cracking and discoloration. All of the sports physicians' items were also considered important by the athletes, but sport-related pain and limitations were regarded by many athletes as a natural part of their sport.
Discrepancies exist between the opinions of young athletes and sports physicians on sport-related pain reporting and competing regardless of pain or limitations. Although clinicians may be inclined to focus on these aspects, they are advised to also inquire specifically about limitations and pain during daily life activities in young athletes with overuse wrist injuries.
The role of intelligent agents becomes more social as they are expected to act in direct interaction, involvement and/or interdependency with humans and other artificial entities, as in Human-Agent ...Teams (HAT). The highly interdependent and dynamic nature of teamwork demands correctly calibrated trust among team members. Trust violations are an inevitable aspect of the cycle of trust and since repairing damaged trust proves to be more difficult than building trust initially, effective trust repair strategies are needed to ensure durable and successful team performance. The aim of this study was to explore the effectiveness of different trust repair strategies from an intelligent agent by measuring the development of human trust and advice taking in a Human-Agent Teaming task. Data for this study were obtained using a task environment resembling a first-person shooter game. Participants carried out a mission in collaboration with their artificial team member. A trust violation was provoked when the agent failed to detect an approaching enemy. After this, the agent offered one of four trust repair strategies, composed of the apology components
explanation
and
expression of regret
(either one alone, both or neither). Our results indicated that expressing regret was crucial for effective trust repair. After trust declined due to the violation by the agent, trust only significantly recovered when an expression of regret was included in the apology. This effect was stronger when an explanation was added. In this context, the intelligent agent was the most effective in its attempt of rebuilding trust when it provided an apology that was both affective, and informational. Finally, the implications of our findings for the design and study of Human-Agent trust repair are discussed.
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