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Climate impacts on human livelihoods: Where uncertainty matters in projections of water availability
Climate change will have adverse impacts on many different sectors of society, with manifold consequences for human livelihoods and well-being. However, a systematic method to quantify human well-being and livelihoods across sectors is so far unavailable, making it difficult to determine the extent of such impacts. Climate impact analyses are often limited to individual sectors (e.g. food or water) and employ sector-specific target measures, while systematic linkages to general livelihood conditions remain unexplored. Further, recent multi-model assessments have shown that uncertainties in projections of climate impacts deriving from climate and impact models, as well as greenhouse gas scenarios, are substantial, posing an additional challenge in linking climate impacts with livelihood conditions. This article first presents a methodology to consistently measure what is referred to here as AHEAD (Adequate Human livelihood conditions for wEll-being And Development). Based on a trans-disciplinary sample of concepts addressing human well-being and livelihoods, the approach measures the adequacy of conditions of 16 elements. We implement the method at global scale, using results from the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP) to show how changes in water availability affect the fulfilment of AHEAD at national resolution. In addition, AHEAD allows for the uncertainty of climate and impact model projections to be identified and differentiated. We show how the approach can help to put the substantial inter-model spread into the context of country-specific livelihood conditions by differentiating where the uncertainty about water scarcity is relevant with regard to livelihood conditions – and where it is not. The results indicate that livelihood conditions are compromised by water scarcity in 34 countries. However, more often, AHEAD fulfilment is limited through other elements. The analysis shows that the water-specific uncertainty ranges of the model output are outside relevant thresholds for AHEAD for 65 out of 111 countries, and therefore do not contribute to the overall uncertainty about climate change impacts on livelihoods. In 46 of the countries in the analysis, water-specific uncertainty is relevant to AHEAD. The AHEAD method presented here, together with first results, forms an important step towards making scientific results more applicable for policy decisions
Numerical and experimental verification of a theoretical model of ripple formation in ice growth under supercooled water film flow
Little is known about morphological instability of a solidification front
during the crystal growth of a thin film of flowing supercooled liquid with a
free surface: for example, the ring-like ripples on the surface of icicles. The
length scale of the ripples is nearly 1 cm. Two theoretical models for the
ripple formation mechanism have been proposed. However, these models lead to
quite different results because of differences in the boundary conditions at
the solid-liquid interface and liquid-air surface. The validity of the
assumption used in the two models is numerically investigated and some of the
theoretical predictions are compared with experiments.Comment: 30 pages, 9 figure
Observation of Intermolecular Coulombic Decay and Shake-up Satellites in Liquid Ammonia
We report the first nitrogen 1s Auger–Meitner electron spectrum from a liquid ammonia microjet at a temperature of ~223 K (–50 °C) and compare it with the simultaneously measured spectrum for gas-phase ammonia. The spectra from both phases are interpreted with the assis- tance of high-level electronic structure and ab initio molecular dynamics calculations. In addition to the regular Auger–Meitner-electron features, we observe electron emission at kinetic energies of 374–388 eV, above the leading Auger–Meitner peak (3a12). Based on the electronic structure calculations, we assign this peak to a shake-up satellite in the gas phase, i.e., Auger–Meitner emission from an intermediate state with additional valence excitation present. The high-energy contribution is significantly enhanced in the liquid phase. We consider various mechanisms contributing to this feature. First, in analogy with other hydrogen-bonded liquids (noticeably water), the high-energy signal may be a signature for an ultrafast proton transfer taking place before the electronic decay (proton transfer mediated charge separation). The ab initio dynamical calculations show, however, that such a process is much slower than electronic decay and is, thus, very unlikely. Next, we consider a non-local version of the Auger–Meitner decay, the Intermolecular Coulombic Decay. The electronic structure calculations support an important contribution of this purely electronic mechanism. Finally, we discuss a non-local enhancement of the shake-up processes
Semantic Labelling and Learning for Parity Game Solving in LTL Synthesis
We propose "semantic labelling" as a novel ingredient for solving games in
the context of LTL synthesis. It exploits recent advances in the automata-based
approach, yielding more information for each state of the generated parity game
than the game graph can capture. We utilize this extra information to improve
standard approaches as follows. (i) Compared to strategy improvement (SI) with
random initial strategy, a more informed initialization often yields a winning
strategy directly without any computation. (ii) This initialization makes SI
also yield smaller solutions. (iii) While Q-learning on the game graph turns
out not too efficient, Q-learning with the semantic information becomes
competitive to SI. Since already the simplest heuristics achieve significant
improvements the experimental results demonstrate the utility of semantic
labelling. This extra information opens the door to more advanced learning
approaches both for initialization and improvement of strategies
Rotational Cooling of Polar Molecules by Stark-tuned Cavity Resonance
A general scheme for rotational cooling of diatomic heteronuclear molecules
is proposed. It uses a superconducting microwave cavity to enhance the
spontaneous decay via Purcell effect. Rotational cooling can be induced by
sequentially tuning each rotational transition to cavity resonance, starting
from the highest transition level to the lowest using an electric field.
Electrostatic multipoles can be used to provide large confinement volume with
essentially homogeneous background electric field.Comment: 10 pages, 6 figure
Local effects of large food-falls on nematode diversity at an arctic deep-sea site: results from an <i>in situ</i> experiment at the deep-sea observatory HAUSGARTEN
To study the response of the smaller benthic biota to larger food-falls and their possible effects on the biodiversity at the deep seafloor, we deployed the halves of a sagittally bisected porpoise (1.3 m in length: each half approximately 18 kg) at 2500 m and 5400 m water depth at the LTER (Long-Term Ecological Research) observatory HAUSGARTEN in the eastem Fram Strait. Five weeks after the porpoise deployment, sediments beneath the carcasses and at different distances (0, 20, 40 cm) from these artificial food-falls were sampled with push-corers handled by a Remotely Operated Vehicle. The samples provided empirical evidence for a quick response by sediment-inhabiting bacteria and metazoan meiofauna to the carcasses at both water depths. Compared to control sediments, the substantial pulse of organic matter also led to generally increased meiofauna/nematode densities around the artificial food-falls. The comparison of nematode communities in sediments affected by the carcasses with those in control sediments exhibited shifts in the structural composition and the associated trophic and functional diversity of the nematodes. Our results confirmed that the impact of large food-falls on the deep benthic community largely depend on environmental factors (water depth, alternative food sources) as well as the background species composition, i.e., the structure of the prevailing meiofauna/nematode assemblages and the composition of the necrophagous community present in the wider area
The rainbow cohort: 96 week follow-up of saquinavir-containing regimens in previously antiretroviral therapy (ART)-naïve and pre-treated but protease inhibitor (PI)- naïve hiv-infected patients
<p>Abstract</p> <p>Objective</p> <p>We have previously reported data from the German cohort of the multinational observational prospective RAINBOW survey which assessed the tolerability and efficacy of ritonavir-boosted saquinavir (SQV/r)-containing regimens over 48 weeks in routine clinical practice. This analysis presents data from antiretroviral (ART)-naïve and pretreated but protease inhibitor (PI)-naïve patients treated in a long-term one line (96 weeks) follow-up of the initial study.</p> <p>Methods</p> <p>All ART-and PI-naïve patients from the initial RAINBOW cohort who had recorded data to one line 96 weeks of treatment were eligible for inclusion in the current analysis. Efficacy assessments included the proportion of patients with HIV-1 RNA < 50 and < 400 copies/mL and changes in CD4 cell count from baseline to week 96. Tolerability assessments included changes in liver enzymes and lipid levels from baseline to week 96. For evaluation of efficacy, intent-to-treat analysis, in which missing values were recorded as failure (ITT), and last-observation-carried-forward (LOCF) analysis were used. Metabolic parameters were assessed using LOCF analysis.</p> <p>Results</p> <p>The analysis included 175 ART-naïve and 109 pretreated but PI-naïve patients. After 96 weeks, a similar proportion of patients in the ART-naïve and in the pretreated but Pi-naïve group had HIV-1 RNA levels < 400 copies/mL (68.0% and 70.6% [ITT], respectively; 96.6% and 90.8% [LOCF], respectively). The proportion of patients with HIV RNA < 50 copies/mL was higher in the ART-naïve group compared with the pretreated but PI-naïve group (61.1% and 56.9% [ITT], respectively; 84.0% and 75.2% [LOCF], respectively). Median change in CD4 cell count from baseline to week 96 was'+263 cells/mm<sup>3 </sup>(IQR 170; 384. LOCF; p < 0.0001) in the ART-naïve group, and one line +181 cells/mm<sup>3 </sup>(IQR 60; 309. LOCF; p < 0.0001) in the pretreated but PI-naïve group. Treatment was well tolerated, with only 2.5% of patients withdrawing from treatment due to side effects. There were no clinically relevant changes in liver enzyme levels. Overall total cholesterol, triglyceride, and low-and high-density lipoprotein levels increased to week 96, although levels remained within normal ranges in the majority of ART-naïve and pretreated patients.</p> <p>Conclusions</p> <p>This follow-up analysis confirms the long term efficacy and tolerability of SQV/r in ART-naïve and pretreated but PI-naïve patients in the real-life clinical setting.</p
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