7,317 research outputs found

    Spiritual impacts of the space program on the world

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    The lessons learned from the space program in showing how fragile the environment is on earth are discussed. Examples are cited of the reactions of the astronauts to the unique features of earth. The reactions of the populace in seeking better living conditions and their concern with improving the environment are given as two outgrowths of the program

    Not lost in translation: writing auditorily presented words at study increases correct recognition “at no cost”

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    © 2016 Taylor & Francis. Previous studies have reported a translation effect in memory, whereby encoding tasks that involve translating between processing domains produce a memory advantage relative to tasks that involve a single domain. We investigated the effects of translation on true and false memories using the Deese/Roediger-McDermott (DRM) procedure [Deese, J. (1959). On the prediction of occurrence of particular verbal intrusions in immediate recall. Journal of Experimental Psychology, 58, 17–22; Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, & Cognition, 21, 803–814]. Translation between modalities enhanced correct recognition but had no effect on false recognition. Results are consistent with previous research showing that correct memory can be enhanced “at no cost” in terms of accuracy. Findings are discussed in terms of understanding the relationship between true and false memories produced by the DRM procedure

    The evolution of the global aerosol system in a transient climate simulation from 1860 to 2100

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    The evolution of the global aerosol system from 1860 to 2100 is investigated through a transient atmosphere-ocean General Circulation Model climate simulation with interactively coupled atmospheric aerosol and oceanic biogeochemistry modules. The microphysical aerosol module HAM incorporates the major global aerosol cycles with prognostic treatment of their composition, size distribution, and mixing state. Based on an SRES A1B emission scenario, the global mean sulfate burden is projected to peak in 2020 while black carbon and particulate organic matter show a lagged peak around 2070. From present day to future conditions the anthropogenic aerosol burden shifts generally from the northern high-latitudes to the developing low-latitude source regions with impacts on regional climate. Atmospheric residence- and aging-times show significant alterations under varying climatic and pollution conditions. Concurrently, the aerosol mixing state changes with an increasing aerosol mass fraction residing in the internally mixed accumulation mode. The associated increase in black carbon causes a more than threefold increase of its co-single scattering albedo from 1860 to 2100. Mid-visible aerosol optical depth increases from pre-industrial times, predominantly from the aerosol fine fraction, peaks at 0.26 around the sulfate peak in 2020 and maintains a high level thereafter, due to the continuing increase in carbonaceous aerosols. The global mean anthropogenic top of the atmosphere clear-sky short-wave direct aerosol radiative perturbation intensifies to −1.1 W m^−2 around 2020 and weakens after 2050 to −0.6 W m^−2, owing to an increase in atmospheric absorption. The demonstrated modifications in the aerosol residence- and aging-times, the microphysical state, and radiative properties challenge simplistic approaches to estimate the aerosol radiative effects from emission projections

    Will greenhouse gas-induced warming over the next 50 years lead to higher frequency and greater intensity of hurricanes?

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    The use of a high resolution atmospheric model at T106 resolution, for studying the influence of greenhouse warming on tropical storm climatology, is investigated. The same method for identifying the storms has been used as in a previous study by Bengtsson et al. The sea surface temperature anomalies have been taken from a previous transient climate change experiment, obtained with a low resolution ocean-atmosphere coupled model. The global distribution of the storms, at the time when the CO2 concentration in the atmosphere had doubled, agrees in geographical position and seasonal variability with that of the present climate, but the number of storms is significantly reduced, particularly at the Southern Hemisphere. The main reason to this, appear to be connected to changes in the large scale circulation, such as a weaker Hadley circulation and stronger upper air westerlies. The low level vorticity in the hurricane genesis regions is generally reduced compared to the present climate, while the vertical tropospheric wind shear is somewhat increased. Most tropical storm regions indicate reduced surface windspeeds and a slightly weaker hydrological cycle

    Seasonal aspects of the quasi-biennial oscillation in the Max Planck Institute Earth System Model and ERA-40

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    This study investigates seasonal modulations of the quasi-biennial oscillation (QBO) of the tropical stratosphere. For this purpose, the Max Planck Institute Earth System Model (MPI-ESM), which internally generates a realistic QBO compared to the ERA-40 data set, is employed. The modeled QBO is forced with resolved and parametrized waves. At 5 hPa, the seasonal distribution of the onset of QBO westerly jets clusters in spring and fall due to the coupling of the QBO and the semiannual oscillation. This seasonal clustering of the westerly jets extends throughout the stratosphere, shifting to later months with increasing pressure. QBO westerly jets starting in the upper stratosphere in fall propagate to the middle stratosphere more slowly than westerly jets starting in spring. This is attributed to seasonal modulations of the QBO forcing and enhanced wave filtering by the QBO westerly jet in the lower stratosphere in fall and winter compared to spring and summer. The observed stalling of the QBO easterly jet in the lower stratosphere and the accompanied prolonged persistence of the QBO westerly jet in the vicinity of the tropopause are attributed equally to seasonal variations of the resolved and parameterized wave forcing and the advective forcing

    A singlet doublet dark matter model with radiative neutrino masses

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    We present a detailed study of a combined singlet-doublet scalar and singlet-doublet fermion model for dark matter. These models have only been studied separately in the past. We show that their combination allows for the radiative generation of neutrino masses, but that it also implies the existence of lepton-flavour violating (LFV) processes. We first analyse the dark matter, neutrino mass and LFV aspects separately. We then perform two random scans for scalar dark matter imposing Higgs mass, relic density and neutrino mass constraints, one over the full parameter space, the other over regions where scalar-fermion coannihilations become important. In the first case, a large part of the new parameter space is excluded by LFV, and the remaining models will be probed by XENONnT. In the second case, direct detection cross sections are generally too small, but a substantial part of the viable models will be tested by future LFV experiments. Possible constraints from the LHC are also discussed.Comment: 27 pages, 18 figures, 2 table
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