129 research outputs found
Hryciuk, Grzegorz/Ruchniewicz, MaĆgorzata/Szaynok, BoĆŒena/Ć»bikowski, Adrzej: Atlas Zwangsumsiedlung, Flucht und Vertreibung. Ostmitteleuropa 1939â1959. Polen, Deutsche, Juden, Ukrainer
Radiative Impacts of the 2011 Abrupt Drops in Water Vapor and Ozone in the Tropical Tropopause Layer
An abrupt drop in tropical tropopause layer (TTL) water vapor, similar to that observed in 2000, recently occurred in 2011, and was concurrent with reductions in TTL temperature and ozone. Previous studies have indicated that such large water vapor variability can have significant radiative impacts. This study uses Aura Microwave Limb Sounder observations, the Stratospheric Water Vapor and Ozone Satellite Homogenized dataset, and two radiative transfer models to examine the radiative effects of the observed changes in TTL water vapor and ozone on TTL temperatures and global radiative forcing (RF). The analyses herein suggest that quasi-isentropic poleward propagation of TTL water vapor reductions results in a zonal-mean structure with âwingsâ of extratropical water vapor reductions, which account for about half of the 2011 abrupt drop global radiative impact. RF values associated with the mean water vapor concentrations differences between 2012/13 and 2010/11 are between â0.01 and â0.09 W mâ»ÂČ, depending upon the altitude above which perturbations are considered. TTL water vapor and ozone variability during this period jointly lead to a transient radiative cooling of ~0.25â0.5 K in layers below the tropopause. The 2011 abrupt drop also prolonged the reduction in stratospheric water vapor that followed the 2000 abrupt drop, providing a longer-term radiative forcing of climate. Water vapor concentrations from 2005 to 2013 are lower than those from 1990 to 1999, resulting in a RF between these periods of about â0.045 W mâ»ÂČ, approximately 12% as large as, but of opposite sign to, the concurrent estimated CO[subscript 2] forcing.United States. National Aeronautics and Space Administration (NNX14AK83H)National Science Foundation (U.S.) (AGS-1342810)National Science Foundation (U.S.) (AGS-1461517
Composable and Finite Computational Security of Quantum Message Transmission
Recent research in quantum cryptography has led to the development of schemes
that encrypt and authenticate quantum messages with computational security. The
security definitions used so far in the literature are asymptotic, game-based,
and not known to be composable. We show how to define finite, composable,
computational security for secure quantum message transmission. The new
definitions do not involve any games or oracles, they are directly operational:
a scheme is secure if it transforms an insecure channel and a shared key into
an ideal secure channel from Alice to Bob, i.e., one which only allows Eve to
block messages and learn their size, but not change them or read them. By
modifying the ideal channel to provide Eve with more or less capabilities, one
gets an array of different security notions. By design these transformations
are composable, resulting in composable security.
Crucially, the new definitions are finite. Security does not rely on the
asymptotic hardness of a computational problem. Instead, one proves a finite
reduction: if an adversary can distinguish the constructed (real) channel from
the ideal one (for some fixed security parameters), then she can solve a finite
instance of some computational problem. Such a finite statement is needed to
make security claims about concrete implementations.
We then prove that (slightly modified versions of) protocols proposed in the
literature satisfy these composable definitions. And finally, we study the
relations between some game-based definitions and our composable ones. In
particular, we look at notions of quantum authenticated encryption and QCCA2,
and show that they suffer from the same issues as their classical counterparts:
they exclude certain protocols which are arguably secure.Comment: 43+11 pages, 18 figures, v2: minor changes, extended version of the
published pape
The role of large-scale dynamics in an exceptional sequence of severe thunderstorms in Europe MayâJune 2018
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High-Level Control System in C#*
We have started upgrading the control room programs for the injector at the Advanced Light Source (ALS). We chose to program in C* exclusively on the .NET Framework to create EPICS client programs on Windows Vista PCs. This paper reports the status of this upgrade project
Imaging of heart disease in women: review and case presentation
Cardiovascular diseases (CVD) remain the leading cause of mortality worldwide. Although major diagnostic and therapeutic advances have significantly improved the prognosis of patients with CVD in the past decades, these advances have less benefited women than age-matched men. Noninvasive cardiac imaging plays a key role in the diagnosis of CVD. Despite shared imaging features and strategies between both sexes, there are critical sex disparities that warrant careful consideration, related to the selection of the most suited imaging techniques, to technical limitations, and to specific diseases that are overrepresented in the female population. Taking these sex disparities into consideration holds promise to improve management and alleviate the burden of CVD in women. In this review, we summarize the specific features of cardiac imaging in four of the most common presentations of CVD in the female population including coronary artery disease, heart failure, pregnancy complications, and heart disease in oncology, thereby highlighting contemporary strengths and limitations. We further propose diagnostic algorithms tailored to women that might help in selecting the most appropriate imaging modality
Groundwater depletion embedded in international food trade
Recent hydrological modelling1 and Earth observations2,3 have located and quantified alarming rates of groundwater depletion worldwide. This depletion is primarily due to water withdrawals for irrigation1,2,4, but its connection with the main driver of irrigation, global food consumption, has not yet been explored. Here we show that approximately eleven per cent of non-renewable groundwater use for irrigation is embedded in international food trade, of which two-thirds are exported by Pakistan, the USA and India alone. Our quantification of groundwater depletion embedded in the worldâs food trade is based on a combination of global, cropspecific estimates of non-renewable groundwater abstraction and international food trade data. A vast majority of the worldâs population lives in countries sourcing nearly all their staple crop imports from partners who deplete groundwater to produce these crops, highlighting risks for global food and water security. Some countries, such as the USA, Mexico, Iran and China, are particularly exposed to these risks because they both produce and import food irrigated from rapidly depleting aquifers. Our results could help to improve the sustainability of global food production and groundwater resource management by identifying priority regions and agricultural products at risk as well as the end consumers of these products
Radiative Forcing From the 2014â2022 Volcanic and Wildfire Injections
Volcanic and wildfire events between 2014 and 2022 injected âŒ3.2 Tg of sulfur dioxide and 0.8 Tg of smoke aerosols into the stratosphere. With injections at higher altitudes and lower latitudes, the simulated stratospheric lifetime of the 2014â2022 injections is about 50% longer than the volcanic 2005â2013 injections. The simulated global mean effective radiative forcing (ERF) of 2014â2022 is â0.18 W mâ2, âŒ40% of the ERF of the period of 1991â1999 with a large-magnitude volcanic eruption (Pinatubo). Our climate model suggests that the stratospheric smoke aerosols generate âŒ60% more negative ERF than volcanic sulfate per unit aerosol optical depth. Studies that fail to account for the different radiative properties of wildfire smoke relative to volcanic sulfate will likely underestimate the negative stratospheric forcings. Our analysis suggests that stratospheric injections offset 20% of the increase in global mean surface temperature between 2014â2022 and 1999â2002
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RECENT BEAM MEASUREMENTS AND NEW INSTRUMENTATION AT THE ADVANCED LIGHT SOURCE
The Advanced Light Source (ALS) in Berkeley was the first of the soft x-ray third generation light source ever built, and since 1993 has been in continuous and successful operation serving a large community of users in the VUV and soft x-ray community. During these years the storage ring underwent through several important upgrades that allowed maintaining the performance of this veteran facility at the forefront. The ALS beam diagnostics and instrumentation have followed a similar path of innovation and upgrade and nowadays include most of the modem and last generation devices and technologies that are commercially available and used in the recently constructed third generation light sources. In this paper we will not focus on such already widely known systems, but we will concentrate our effort in the description of some measurements techniques, instrumentation and diagnostic systems specifically developed at the ALS and used during the last few years
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