An automated atmospheric sampling system operating on 747 airliners

An air sampling system that automatically measures the temporal and spatial distribution of selected particulate and gaseous constituents of the atmosphere has been installed on a number of commercial airliners and is collecting data on commercial air routes covering the world. Measurements of constituents related to aircraft engine emissions and other pollutants are made in the upper troposphere and lower stratosphere (6 to 12 km) in support of the Global Air Sampling Program (GASP). Aircraft operated by different airlines sample air at latitudes from the Arctic to Australia. This system includes specialized instrumentation for measuring carbon monoxide, ozone, water vapor, and particulates, a special air inlet probe for sampling outside air, a computerized automatic control, and a data acquisition system. Air constituents and related flight data are tape recorded in flight for later computer processing on the ground

Voter Model Perturbations and Reaction Diffusion Equations

We consider particle systems that are perturbations of the voter model and show that when space and time are rescaled the system converges to a solution of a reaction diffusion equation in dimensions $d \ge 3$. Combining this result with properties of the PDE, some methods arising from a low density super-Brownian limit theorem, and a block construction, we give general, and often asymptotically sharp, conditions for the existence of non-trivial stationary distributions, and for extinction of one type. As applications, we describe the phase diagrams of three systems when the parameters are close to the voter model: (i) a stochastic spatial Lotka-Volterra model of Neuhauser and Pacala, (ii) a model of the evolution of cooperation of Ohtsuki, Hauert, Lieberman, and Nowak, and (iii) a continuous time version of the non-linear voter model of Molofsky, Durrett, Dushoff, Griffeath, and Levin. The first application confirms a conjecture of Cox and Perkins and the second confirms a conjecture of Ohtsuki et al in the context of certain infinite graphs. An important feature of our general results is that they do not require the process to be attractive.Comment: 106 pages, 7 figure

Cross-sectional and longitudinal associations between receptive arts engagement and loneliness among older adults

Purpose Loneliness in older adulthood is a societal and public health challenge warranting identification of sustainable and community-based protective factors. This study investigated whether frequency of receptive arts engagement is associated with lower odds of loneliness in older adults. Methods We used data of respondents from waves 2 (2004–2005) and 7 (2014–2015) of the English Longitudinal Study of Ageing (ELSA) and examined cross-sectional (n = 6222) and longitudinal (n = 3127) associations between frequency of receptive arts engagement (including visits to the cinema, museums/galleries/exhibitions, theatre/concerts/opera) and odds of loneliness (cut-off ≥ 6 on three-item short form of the Revised UCLA Loneliness Scale). We fitted logistic regression models adjusted for a range of sociodemographic, economic, health and social, community and civic engagement factors. Results Cross-sectionally, we found dose–response negative associations between engagement with all receptive arts activities and odds of loneliness. Prospectively, in the fully-adjusted models we found most robust evidence for the negative association between engagement with museums/galleries/exhibitions and odds of loneliness (OR = 0.68, 95% CI 0.48–0.95) for those who engaged every few months or more often compared with those who never engaged. We found weaker evidence for lower odds of loneliness for more frequent engagement with theatre/concerts/opera. Conclusions Frequent engagement with certain receptive arts activities and venues, particularly museums, galleries and exhibitions, may be a protective factor against loneliness in older adults. Future research is needed to identify the mechanisms through which this process may occur, leading to better understanding of how arts activities and venues can reduce loneliness among older adults

Critical Fields and Critical Currents in MgB2

We review recent measurements of upper (Hc2) and lower (Hc1) critical fields in clean single crystals of MgB2, and their anisotropies between the two principal crystallographic directions. Such crystals are far into the "clean limit" of Type II superconductivity, and indeed for fields applied in the c-direction, the Ginzburg-Landau parameter k is only about 3, just large enough for Type II behaviour. Because m0Hc2 is so low, about 3 T for fields in the c-direction, MgB2 has to be modified for it to become useful for high-current applications. It should be possible to increase Hc2 by the introduction of strong electron scattering (but because of the electronic structure and the double gap that results, the scatterers will have to be chosen carefully). In addition, pinning defects on a scale of a few nm will have to be engineered in order to enhance the critical current density at high fields.Comment: BOROMAG Conference Invited paper. To appear in Supercond. Sci. Tec

Efimov states and their Fano resonances in a neutron-rich nucleus

Asymmetric resonances in elastic n+$^{19}$C scattering are attributed to Efimov states of such neutron-rich nuclei, that is, three-body bound states of the n+n+$^{18}$C system when none of the pairs is bound or some of them only weakly bound. By fitting to the general resonance shape described by Fano, we extract resonance position, width, and the "Fano profile index". While Efimov states have been discussed extensively in many areas of physics, there is only one very recent experimental observation in trimers of cesium atoms. The conjunction that we present of the Efimov and Fano phenomena may lead to experimental realization in nuclei.Comment: 4 double-column pages, 3 figure

Differentiating anxiety from fear: An experimental-pharmacological approach

Gray’s theory of personality postulates that fear and anxiety are distinct emotional systems with only the latter being sensitive to anxiolytic drugs. His work was mainly based on animal research and translational studies validating his theory are scarce. Previous work in humans showed an influence of the benzodiazepine lorazepam on both systems, however, dependent on dosage (1 and 2mg) and personality differences in negative emotionality. The present study aims to replicate these findings, and in addition tests the drug threshold effect by introducing a lower dosage of 0.5mg lorazepam. Fifty healthy adults (23 males, agemean 22.40, SD±3.68) participated in an experimental threat-avoidance paradigm designed to dissociate risk assessment intensity (RAI, reflecting anxiety) and flight intensity (FI, reflecting fear) and completed two self-report questionnaires assessing facets of negative emotionality (Spielberger Trait Anxiety Inventory and Fear Survey Schedule). In a randomized placebo-controlled within-subject design, 0.5mg and 1mg of lorazepam were applied per os. Saccadic peak velocity was assessed by means of eye-tracking in order to control for sedating drug effects. Results showed the expected and specific anxiolytic effect of lorazepam on RAI, however only in the 0.5mg condition. FI was not influenced by lorazepam and previous findings of interaction effects of lorazepam with self-reported negative emotionality could not be corroborated. Overall, this study demonstrates anxiolytic effects of lorazepam in dosages ≤ 1mg in the absence of a drug effect on fear using a translational behavioural task. However, a putative moderating role of personality on defensive behaviour has to be clarified in future research

Cross‑sectional and longitudinal associations between receptive arts engagement and loneliness among older adults

Purpose: Loneliness in older adulthood is a societal and public health challenge warranting identification of sustainable and community-based protective factors. This study investigated whether frequency of receptive arts engagement is associated with lower odds of loneliness in older adults. Methods: We used data of respondents from waves 2 (2004–2005) and 7 (2014–2015) of the English Longitudinal Study of Ageing (ELSA) and examined cross-sectional (n = 6222) and longitudinal (n = 3127) associations between frequency of receptive arts engagement (including visits to the cinema, museums/galleries/exhibitions, theatre/concerts/opera) and odds of loneliness (cut-off ≥ 6 on three-item short form of the Revised UCLA Loneliness Scale). We fitted logistic regression models adjusted for a range of sociodemographic, economic, health and social, community and civic engagement factors. Results: Cross-sectionally, we found dose–response negative associations between engagement with all receptive arts activities and odds of loneliness. Prospectively, in the fully-adjusted models we found most robust evidence for the negative association between engagement with museums/galleries/exhibitions and odds of loneliness (OR = 0.68, 95% CI 0.48–0.95) for those who engaged every few months or more often compared with those who never engaged. We found weaker evidence for lower odds of loneliness for more frequent engagement with theatre/concerts/opera. Conclusions: Frequent engagement with certain receptive arts activities and venues, particularly museums, galleries and exhibitions, may be a protective factor against loneliness in older adults. Future research is needed to identify the mechanisms through which this process may occur, leading to better understanding of how arts activities and venues can reduce loneliness among older adults

IEX-1 directly interferes with RelA/p65 dependent transactivation and regulation of apoptosis

The early response gene IEX-1 plays a complex role in the regulation of apoptosis. Depending on the cellular context and the apoptotic stimulus, IEX-1 is capable to either enhance or suppress apoptosis. To further dissect the molecular mechanisms involved in the modulation of apoptosis by IEX-1, we analysed the molecular crosstalk between IEX-1 and the NF-kappa B pathway. Using GST-pulldown assays, a direct interaction of IEX-1 with the C-terminal region of the subunit RelA/p65 harbouring the transactivation domain of the NF-kappa B transcription factor was shown. This interaction negatively regulates RelA/p65 dependent transactivation as shown by GAL4-and luciferase assay and was confirmed for the endogenous proteins by co-immunoprecipitation experiments. Using deletion constructs, we were able to map the C-terminal region of IEX-1 as the critical determinant of the interaction with RelA/p65. We could further show, that IEX-1 mediated NF-kappa B inhibition accounts for the reduced expression of the anti-apoptotic NF-kappa B target genes Bc1-2, Bcl-xL, cIAP1 and cIAP2, thereby sensitizing cells for apoptotic stimuli. Finally, ChIP-assays revealed that IEX-1 associates with the promoter of these genes. Altogether, our findings suggest a critical role of IEX-1 in the NF-kappa B dependent regulation of apoptotic responses. (C) 2007 Elsevier B.V All rights reserved

Resonance between Noise and Delay

We propose here a stochastic binary element whose transition rate depends on its state at a fixed interval in the past. With this delayed stochastic transition this is one of the simplest dynamical models under the influence of ``noise'' and ``delay''. We demonstrate numerically and analytically that we can observe resonant phenomena between the oscillatory behavior due to noise and that due to delay.Comment: 4 pages, 5 figures, submitted to Phys.Rev.Lett Expanded and Added Reference