82 research outputs found
Mass evacuation - human behavior and crowd dynamics - What do we know?
The field of mass evacuation has existed for a long time. Already during the Roman Empire era evacuation problematic was considered. In modern times the field has gained more attention during the last couple of decades, especially for sports grounds and stadiums. Through analysis of some well-known historical crowd disasters and through a literature survey the aim has been to compile the most important findings. The aim has also been to analyze problem areas, knowledge and development opportunities. Regarding the problems of mass evacuation, preventive measures like design and contingency plan is of high importance. In addition there is a need for good communication and to take proper actions when an accident occurs. Some phenomenon that may arise during crowded situations have been found. These phenomenon are an indication that a catastrophic situation might emerge. With knowledge and understanding of those the expectation is, with the help of live video recordings and simulation softwares, to get a warning about the elevated risk for the crowd
Scoring functions for transcription factor binding site prediction
BACKGROUND: Transcription factor binding site (TFBS) prediction is a difficult problem, which requires a good scoring function to discriminate between real binding sites and background noise. Many scoring functions have been proposed in the literature, but it is difficult to assess their relative performance, because they are implemented in different software tools using different search methods and different TFBS representations. RESULTS: Here we compare how several scoring functions perform on both real and semi-simulated data sets in a common test environment. We have also developed two new scoring functions and included them in the comparison. The data sets are from the yeast (S. cerevisiae) genome. Our new scoring function LLBG (least likely under the background model) performs best in this study. It achieves the best average rank for the correct motifs. Scoring functions based on positional bias performed quite poorly in this study. CONCLUSION: LLBG may provide an interesting alternative to current scoring functions for TFBS prediction
the Clean Development Mechanism (CDM) as a new form of governance in climate protection
Die BewÀltigung des Klimawandels ist heute eine der bedeutendsten politischen
Herausforderungen. Das Kyoto-Protokoll ist der am weitesten fortgeschrittene
Prozess der internationalen Staatengemeinschaft im Hinblick auf die
Herausforderungen des Klimawandels. Einer der interessantesten und
innovativsten Bausteine des Kyoto-Protokolls ist der Clean Development
Mechanismus (CDM). Seit seiner Initiierung ist dieser so genannte flexible
Mechanismus der SchlĂŒssel zur Schaffung von volatilen und boomenden MĂ€rkten
fĂŒr Zertifikate fĂŒr die Reduktion von Kohlenstoffemissionen (CERs). Diese
Zertifikate, kurz CERs, sind die ersten international gehandelten GĂŒter, die
durch ein internationales Umweltabkommen geschaffen wurden. WĂ€hrend des
Prozesses der Marktetablierung sind private Akteure wie Firmen,
Projektverifizierer, Carbon Funds und ZertifikatshĂ€ndler zu den fĂŒhrenden
Akteuren des globalen Kohlenstoffmarktes aufgestiegen. Dennoch ist der Markt
weiterhin stark von den politischen Rahmenbedingungen abhÀngig. Die Nachfrage
wird durch die Festlegung von Emissionsreduktionen fĂŒr Nationalstaaten und
deren Emissionsallokationen geschaffen. Der vorliegende Artikel untersucht die
Transformation des Markts, der zunÀchst von öffentlichen Akteuren initiiert,
durch Public Private Partnerships (PPPs) angestoĂen, sich zu einem Markt
entwickelt, wo sich die Regierungen nach und nach zurĂŒckziehen und private
Akteure immer stÀrker Governancefunktionen wahrnehmen. Weiterhin wird der
Status quo des CDM evaluiert und auf verbleibende Forschungsfragen
hingewiesen
Dissection of the Bradyrhizobium japonicum NifA+Ï54 regulon, and identification of a ferredoxin gene ( fdxN ) for symbiotic nitrogen fixation
Hierarchically organized regulatory proteins form a complex network for expression control of symbiotic and accessory genes in the nitrogen-fixing soybean symbiont Bradyrhizobium japonicum. A genome-wide survey of regulatory interactions was made possible with the design of a custom-made gene chip. Here, we report the first use of the microarray in a comprehensive and complete characterization of the B. japonicum NifA+Ï54 regulon which forms an important node in the entire network. Comparative transcript profiles of anaerobically grown wild-type, nifA, and rpoN 1/2 mutant cells were complemented with a position-specific frequency matrix-based search for NifA- and Ï54-binding sites plus a simple operon definition. One of the newly identified NifA+Ï54-dependent genes, fdxN, encodes a ferredoxin required for efficient symbiotic nitrogen fixation, which makes it a candidate for being a direct electron donor to nitrogenase. The fdxN gene has an unconventional, albeit functional Ï54 promoter with the dinucleotide GA instead of the consensus GC motif at position â12. A GC-containing mutant promoter and the atypical GA-containing promoter of the wild type were disparately activated. Expression analyses were also carried out with two other NifA+Ï54 targets (ectC; ahpC). Incidentally, the tiling-like design of the microarray has helped to arrive at completely revised annotations of the ectC- and ahpC-upstream DNA regions, which are now compatible with promoter locations. Taken together, the approaches used here led to a substantial expansion of the NifA+Ï54 regulon size, culminating in a total of 65 genes for nitrogen fixation and diverse other processe
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Intercomparison of in-situ aircraft and satellite aerosol measurements in the stratosphere
Aerosol composition and optical scattering from particles in the lowermost stratosphere (LMS) have been studied by comparing in-situ aerosol samples from the IAGOS-CARIBIC passenger aircraft with vertical profiles of aerosol backscattering obtained from the CALIOP lidar aboard the CALIPSO satellite. Concentrations of the dominating fractions of the stratospheric aerosol, being sulphur and carbon, have been obtained from post-flight analysis of IAGOS-CARIBIC aerosol samples. This information together with literature data on black carbon concentrations were used to calculate the aerosol backscattering which subsequently is compared with measurements by CALIOP. Vertical optical profiles were taken in an altitude range of several kilometres from and above the northern hemispheric extratropical tropopause for the years 2006-2014. We find that the two vastly different measurement platforms yield different aerosol backscattering, especially close to the tropopause where the influence from tropospheric aerosol is strong. The best agreement is found when the LMS is affected by volcanism, i.e., at elevated aerosol loadings. At background conditions, best agreement is obtained some distance (>2 km) above the tropopause in winter and spring, i.e., at likewise elevated aerosol loadings from subsiding aerosol-rich stratospheric air. This is to our knowledge the first time the CALIPSO lidar measurements have been compared to in-situ long-term aerosol measurements. © 2019, The Author(s)
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Influence of volcanic eruptions on midlatitude upper tropospheric aerosol and consequences for cirrus clouds
The influence of downwelling stratospheric sulfurous aerosol on the UT (upper troposphere) aerosol concentrations and on cirrus clouds is investigated using CARIBIC (Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrument Container observations) (between 1999â2002 and 2005â2013) and the cirrus reflectance product from Moderate Resolution Imaging Spectroradiometer (MODIS). The initial period, 1999â2002, was volcanically quiescent after which the sulfurous aerosol in the LMS (lowermost stratosphere) (SLMS) became enhanced by several volcanic eruptions starting 2005. From 2005 to 2008 and in 2013, volcanic aerosol from several tropical eruptions increased SLMS. Due to consequent subsidence, the sulfur loading of the upper troposphere (SUT) was increased by a factor of 2.5 compared to background levels. Comparison of SLMS and SUT during the seasons MarchâJuly and AugustâNovember shows a close coupling of the UT and LMS. Finally, the relationship between SLMS and the cirrus cloud reflectance (CR) retrieved from MODIS spectrometer (on board the satellites Terra and Aqua) is studied. SLMS and CR show a strong anticorrelation, with a factor of 3.5 increase in SLMS and decrease of CR by 8â±â2% over the period 2001â2011. We propose that the increase of SLMS due to volcanism has caused the coinciding cirrus CR decrease, which would be associated with a negative radiative forcing in the Northern Hemisphere midlatitudes
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Significant radiative impact of volcanic aerosol in the lowermost stratosphere
Despite their potential to slow global warming, until recently, the radiative forcing associated with volcanic aerosols in the lowermost stratosphere (LMS) had not been considered. Here we study volcanic aerosol changes in the stratosphere using lidar measurements from the NASA CALIPSO satellite and aircraft measurements from the IAGOS-CARIBIC observatory. Between 2008 and 2012 volcanism frequently affected the Northern Hemisphere stratosphere aerosol loadings, whereas the Southern Hemisphere generally had loadings close to background conditions. We show that half of the global stratospheric aerosol optical depth following the Kasatochi, Sarychev and Nabro eruptions is attributable to LMS aerosol. On average, 30% of the global stratospheric aerosol optical depth originated in the LMS during the period 2008â2011. On the basis of the two independent, high-resolution measurement methods, we show that the LMS makes an important contribution to the overall volcanic forcing
Influence of volcanic eruptions on midlatitude upper tropospheric aerosol and consequences for cirrus clouds â Volc Affects S Aerosol in UT and Cirrus
The influence of downwelling stratospheric sulfurous aerosol on the UT (upper troposphere) aerosol concentrations and on cirrus clouds is investigated using CARIBIC (Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrument Container observations) (between 1999â2002 and 2005â2013) and the cirrus reflectance product from Moderate Resolution Imaging Spectroradiometer (MODIS). The initial period, 1999â2002, was volcanically quiescent after which the sulfurous aerosol in the LMS (lowermost stratosphere) (S) became enhanced by several volcanic eruptions starting 2005. From 2005 to 2008 and in 2013, volcanic aerosol from several tropical eruptions increased S. Due to consequent subsidence, the sulfur loading of the upper troposphere (S) was increased by a factor of 2.5 compared to background levels. Comparison of SLMS and S during the seasons MarchâJuly and AugustâNovember shows a close coupling of the UT and LMS. Finally, the relationship between S and the cirrus cloud reflectance (CR) retrieved from MODIS spectrometer (on board the satellites Terra and Aqua) is studied. S and CR show a strong anticorrelation, with a factor of 3.5 increase in SLMS and decrease of CR by 8 ± 2% over the period 2001â2011. We propose that the increase of S due to volcanism has caused the coinciding cirrus CR decrease, which would be associated with a negative radiative forcing in the Northern Hemisphere midlatitudes
Kevin M. McGeough, Exchange Relationships at Ugarit (Ancient Near Eastern Studies Supplement Series, 26).
This book is the product of the revision of the Doctoral Dissertation defended by the author in 2005 at the University of Pennsylvania. The introductory chapter presents the main objectives of the project: âthis examination shall focus on ... exchange relationships ... More generally, this study seeks to examine economic modalities at Ugarit ... Economic modalities ... are understood here as the emergent structures of the social economy at Ugaritâ (p. 1-2). The author next underlines what he ..
Neurofilament light as an outcome predictor after cardiac arrest : a post hoc analysis of the COMACARE trial
Purpose Neurofilament light (NfL) is a biomarker reflecting neurodegeneration and acute neuronal injury, and an increase is found following hypoxic brain damage. We assessed the ability of plasma NfL to predict outcome in comatose patients after out-of-hospital cardiac arrest (OHCA). We also compared plasma NfL concentrations between patients treated with two different targets of arterial carbon dioxide tension (PaCO2), arterial oxygen tension (PaO2), and mean arterial pressure (MAP). Methods We measured NfL concentrations in plasma obtained at intensive care unit admission and at 24, 48, and 72 h after OHCA. We assessed neurological outcome at 6 months and defined a good outcome as Cerebral Performance Category (CPC) 1-2 and poor outcome as CPC 3-5. Results Six-month outcome was good in 73/112 (65%) patients. Forty-eight hours after OHCA, the median NfL concentration was 19 (interquartile range [IQR] 11-31) pg/ml in patients with good outcome and 2343 (587-5829) pg/ml in those with poor outcome,p <0.001. NfL predicted poor outcome with an area under the receiver operating characteristic curve (AUROC) of 0.98 (95% confidence interval [CI] 0.97-1.00) at 24 h, 0.98 (0.97-1.00) at 48 h, and 0.98 (0.95-1.00) at 72 h. NfL concentrations were lower in the higher MAP (80-100 mmHg) group than in the lower MAP (65-75 mmHg) group at 48 h (median, 23 vs. 43 pg/ml,p = 0.04). PaCO(2)and PaO(2)targets did not associate with NfL levels. Conclusions NfL demonstrated excellent prognostic accuracy after OHCA. Higher MAP was associated with lower NfL concentrations.Peer reviewe
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