1,744 research outputs found
Pandemic SiM - Impact analysis and improvement potentials for pandemic airport security processes
Impacts of the COVID-19 pandemic hit aviation and airports in multiples ways. As air
transport is recovering cautiously from the severe losses due to travel restrictions this
paper examines consequences of measures required to minimize contamination risks
along travel processes at airports. In a simulation model we apply these measures in
an exemplarily way focusing on the security check area of a medium sized European
airport. The paper describes the modelling as well as results and findings of the simulation runs. It will show how capacity, waiting times and waiting space are affected, thus
posing new challenges for airports due to increasing cost, and how further research
could contribute to some relief in this regard
Gekoppelte Passagierflusssimulation zur Optimierung des Turnaroundprozesses
In den Einzelprozessen des Turnarounds nehmen die Passagierbewegungen des Boarding und des Deplaning
eine zentrale Rolle ein, da sie auf dem kritischen Pfad des Turnarounds liegen. Kommt es in einem dieser
Prozesse zu Verzögerungen, so wirkt sich dies sofort auf die Dauer des Gesamtprozesses aus. Ist die
Verzögerung so groß, dass der geplante Take-Off Slot für diesen Flug verpasst wird, wächst die Verzögerung
noch weiter, da ein neuer freier Slot zugewiesen werden muss. und es damit zu einer weiteren
Folgeverspätung kommt. Gleichwohl bewegen sich die Einzelprozesse im Terminal und in der Flugzeugkabine
bereits in ihrem lokalen Optimum. Durch Kopplung einer Passagierflusssimulation im Terminal mit einer
Boardingsimulation in der Flugzeugkabine soll untersucht werden, wie sich mögliche Entwicklungen und
Restriktionen in einem dieser Bereiche auf die Gesamtprozesse der Reisekette des Passagiers auswirken
können. Zusätzlich soll mit Hilfe dieser gekoppelten Simulation langfristig bewertet werden, ob Maßnahmen
die bereits im Terminal vorbereitet werden können, helfen das Boarding in der Kabine effizienter zu gestalten
The rigid amphipathic fusion Inhibitor dUY11 acts through photosensitization of viruses
Copyright © 2014, American Society for Microbiology. All Rights Reserved.Supplemental material for this article may be found at http://dx.doi.org/10.1128
/JVI.02907-13.Rigid amphipathic fusion inhibitors (RAFIs) are lipophilic inverted-cone-shaped molecules thought to antagonize the membrane curvature transitions that occur during virus-cell fusion and are broad-spectrum antivirals against enveloped viruses (Broad-SAVE). Here, we show that RAFIs act like membrane-binding photosensitizers: their antiviral effect is dependent on light and the generation of singlet oxygen (1O2), similar to the mechanistic paradigm established for LJ001, a chemically unrelated class of Broad-SAVE. Photosensitization of viral membranes is a common mechanism that underlies these Broad-SAVE.This work was supported by NIH grants U01 AI070495, U01 AI082100, R01 AI069317, and U54 AI065359 (PSWRCE) (to B.L.) and by Fundação para a Ciência e a Tecnologia-Ministério da Educação e Ciência (Portugal) project DELIN-HIVERA/0002/2013 and fellowship SFRH/BPD/72037/2010 (to N.C.S. and A.H., respectively
Post-Pandemic Impact Analysis for airport processes from security to boarding – How to respond the next pandemic
The COVID-19 pandemic globally affected the complete transport sector and especially passenger air transport with nosediving traffic numbers, wide-ranging travel restrictions and long-lasting uncertainties (see IATA, 2020). As air travel starts to recover cautiously from severe losses of traffic volumes over the pre-pandemic year 2019 and travel restrictions are relaxing, air transport providers have to ensure that passengers as well as people working within the air transport sector will remain safe and be prepared for the next Pandemic. For Example, arboviruses have the potential to spark the next epidemic, warns the World Health Organisation (WHO) and it might only be a question of time when the next pandemic will rise. Airports need to prepare to cope with the next pandemic efficiently and effectively. For this purpose, we develop a toolbox to analyse and evaluate operational measures along the process chain of travelling at an airport.This paper examines the contamination risks at airports covering the travel process from security checks to aircraft seat. In our study we examine the possibility of an infection by dint of simulation with the Pandemic Simulation Model (Pandemic SiM). For this purpose, we advanced an earlier version of Pandemic SiM that only covered the security check area by adding typical boarding processes of a medium sized European airport. The model is based on a real European airport serving around 12 million passengers per year (in 2019). The simulation model incorporates a new algorithm calculating the probability of spreading a virus (like COVID-19) via droplet, airborne or contact transmission during different airport travel processes along the travel chain. The algorithm considers different infection situations and incidence values and allows for a quantification of infection risks per individual simulated passenger. Based on the output of the simulations of the process chain in combination with that algorithm we can show the effectiveness of measures like social distancing and their consequences to minimize contamination risks along travel processes at airports. The paper describes the modelling, the algorithm to calculate contamination risks, as well as results and findings of the simulation runs. It will show how contamination risks, capacity, waiting times and waiting space are affected. This will provide airport operators with decision support for challenges arising from the need to be prepared for the next pandemic
Pygmy dipole strength close to particle-separation energies - the case of the Mo isotopes
The distribution of electromagnetic dipole strength in 92, 98, 100 Mo has
been investigated by photon scattering using bremsstrahlung from the new ELBE
facility. The experimental data for well separated nuclear resonances indicate
a transition from a regular to a chaotic behaviour above 4 MeV of excitation
energy. As the strength distributions follow a Porter-Thomas distribution much
of the dipole strength is found in weak and in unresolved resonances appearing
as fluctuating cross section. An analysis of this quasi-continuum - here
applied to nuclear resonance fluorescence in a novel way - delivers dipole
strength functions, which are combining smoothly to those obtained from
(g,n)-data. Enhancements at 6.5 MeV and at ~9 MeV are linked to the pygmy
dipole resonances postulated to occur in heavy nuclei.Comment: 6 pages, 5 figures, proceedings Nuclear Physics in Astrophysics II,
May 16-20, Debrecen, Hungary. The original publication is available at
www.eurphysj.or
Heat and Charge Transport Properties of MgB2
A polycrystalline sample of the MgB_2 superconductor was investigated by
measurements of the electrical resistivity, the thermopower and the thermal
conductivity in the temperature range between 1.8K and 300K in zero magnetic
field. The electrical resistivity shows a superconducting transition at
T_c=38.7K and, similarly to borocarbides, a T^2.4 behaviour up to 200K. The
electron diffusion thermopower and its bandstructure-derived value indicate the
dominant hole character of the charge carriers. The total thermopower can be
explained by the diffusion term renormalized by a significant electron-phonon
interaction and a phonon drag term. In the thermal conductivity, for decreasing
temperature, a significant decrease below T_c is observed resulting in a T^3
behaviour below 7K. The reduced Lorenz number exhibits values smaller than 1
and a characteristic minimum which resembles the behaviour of non-magnetic
borocarbides.Comment: 7 pages, 5 figures; added references and minor changes; accepted for
publication in Physica
Insights from Multimodal Preclinical Imaging in Immunocompetent Nude Mice
Hydrogels based on gelatin have evolved as promising multifunctional
biomaterials. Gelatin is crosslinked with lysine diisocyanate ethyl ester
(LDI) and the molar ratio of gelatin and LDI in the starting material mixture
determines elastic properties of the resulting hydrogel. In order to
investigate the clinical potential of these biopolymers, hydrogels with
different ratios of gelatin and diisocyanate (3-fold (G10_LNCO3) and 8-fold
(G10_LNCO8) molar excess of isocyanate groups) were subcutaneously implanted
in mice (uni- or bilateral implantation). Degradation and biomaterial-tissue-
interaction were investigated in vivo (MRI, optical imaging, PET) and ex vivo
(autoradiography, histology, serum analysis). Multimodal imaging revealed that
the number of covalent net points correlates well with degradation time, which
allows for targeted modification of hydrogels based on properties of the
tissue to be replaced. Importantly, the degradation time was also dependent on
the number of implants per animal. Despite local mechanisms of tissue
remodeling no adverse tissue responses could be observed neither locally nor
systemically. Finally, this preclinical investigation in immunocompetent mice
clearly demonstrated a complete restoration of the original healthy tissue
Lack of variant specific CD8+T-cell response against mutant and pre-existing variants leads to outgrowth of particular clones in acute hepatitis C
Background: CTL escape mutations have been described during acute hepatitis C in patients who developed chronic disease later on. Our aim was to investigate the mutual relationship between HCV specific CD8+ T cells and evolution of the viral sequence during early acute HCV infection. Results: We sequenced multiple clones of NS3 1406 epitope in 4 HLA-A{*}02 patients with acute hepatitis C genotype 1b infection. Pentamers specific for the variants were used to monitor the corresponding CD8+ T cell response. We observed outgrowth of mutations, which induced only a weak and thus potentially insufficient CD8+ T cell response. In one patient we observed outgrowth of variant epitopes with similarities to a different genotype rather than de novo mutations most probably due to a lack of responsiveness to these likely pre-existing variants. We could show that in acute hepatitis C CTL escape mutations occur much earlier than demonstrated in previous studies. Conclusions: The adaption of the virus to a new host is characterized by a high and rapid variability in epitopes under CD8+ T cell immune pressure. This adaption takes place during the very early phase of acute infection and strikingly some sequences were reduced below the limit of detection at some time points but were detected at high frequency again at later time points. Independent of the observed variability, HCV-specific CD8+ T cell responses decline and no adaption to different or new antigens during the course of infection could be detected
Multivalent grafting of hyperbranched oligo- and polyglycerols shielding rough membranes to mediate hemocompatibility
Hemocompatible materials are needed for internal and extracorporeal biomedical
applications, which should be realizable by reducing protein and thrombocyte
adhesion to such materials. Polyethers have been demonstrated to be highly
efficient in this respect on smooth surfaces. Here, we investigate the
grafting of oligo- and polyglycerols to rough poly(ether imide) membranes as a
polymer relevant to biomedical applications and show the reduction of protein
and thrombocyte adhesion as well as thrombocyte activation. It could be
demonstrated that, by performing surface grafting with oligo- and
polyglycerols of relatively high polydispersity (>1.5) and several reactive
groups for surface anchoring, full surface shielding can be reached, which
leads to reduced protein adsorption of albumin and fibrinogen. In addition,
adherent thrombocytes were not activated. This could be clearly shown by
immunostaining adherent proteins and analyzing the thrombocyte covered area.
The presented work provides an important strategy for the development of
application relevant hemocompatible 3D structured materials
Разработка метода формирования гидридного слоя на внешней поверхности оболочки ТВЭЛа
Работа посвящена разработке метода наводороживания циркониевых оболочек тепловыделяющих элементов для формирования градиента концентрации водорода и гидридов по толщине.Die Arbeit ist der Entwicklung eines Hydrierungsverfahrens von Brennstoffhüllen aus Zirconium bei der Bildung des Gradienten des Wasserstoffkonzentrations in der Dicke gewidmet
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