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  • 1
    Language: English
    In: The journal of physical chemistry. A, 30 June 2011, Vol.115(25), pp.7005-9
    Description: The study of small clusters is intended to fill the knowledge gap between single atoms and bulk material. He nanodroplets are an ideal matrix for preparing and investigating clusters in a superfluid environment. Alkali-metal atoms are only bound very weakly to their surface by van der Waals forces. Due to the formation process, high-spin states of alkali-metal clusters on He nanodroplets are favorably observed, which is in contrast to the abundance in other preparation processes. Until now, the prevailing opinion was that stable clusters of the heavy alkali-metal atoms, rubidium (Rb) and cesium (Cs) on He nanodroplets, are limited to 5 and 3 atoms, respectively (Schulz et al., Phys. Rev. Lett. 2004, 92, 13401). Here, we present stable complexes of Rb(n)⁺ and Cs(n)⁺ consisting of up to n = 30 atoms, with the detection of large alkali-metal clusters being strongly enhanced by one-photon ionization. Our results also suggest that we monitored both high-spin and low-spin state clusters created on nanodroplets. The van der Waals bound high-spin alkali-metal clusters should show strong magnetic behavior, while low-spin states are predicted to exhibit metallic characteristics. Alkali-metal clusters prepared in these two configurations appear to be ideal candidates for investigating nanosized particles with ferromagnetic or metallic properties.
    Keywords: Cesium -- Atomic Properties ; Cesium -- Magnetic Properties ; Helium -- Atomic Properties ; Particle Spin -- Analysis ; Rubidium -- Atomic Properties ; Rubidium -- Magnetic Properties ; Van Der Waals Forces -- Analysis;
    ISSN: 10895639
    E-ISSN: 1520-5215
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  • 2
    Language: English
    In: Journal of Peace Research, January 2012, Vol.49(1), pp.81-96
    Description: The evidence of coming climate change has generated catastrophe-like statements of a future where a warmer, wetter, and wilder climate leads to a surge in migrant streams and gives rise to new wars. Although highly popular in policy circles, few of these claims are based on systematic evidence. Using a most-likely case design on Kenya 1989–2004, with new geographically disaggregated data on armed conflicts below the common civil conflict level, this study finds that climatic factors do influence the risk of conflicts and violent events. The effect is opposite to what should be expected from much of the international relations literature; rather, it supports the observations made by recent anthropological studies. Years with below average rainfall tend to have a peaceful effect on the following year and less robustly so for the current year as well. Little support is found for the notion that scarcity of farmland fuels violence in itself or in election years. More densely populated areas – not areas with a low land per capita ratio – run a higher risk of conflict. Election years systematically see more violence, however. The findings therefore support the notion that large-scale intergroup violence is driven by calculation and political gain rather than desperate scrambles for scarce land, pasture, and water resources.
    Keywords: Climate Change ; Elections ; Kenya ; Land ; Resource Scarcity ; Violence ; International Relations ; Law
    ISSN: 0022-3433
    E-ISSN: 1460-3578
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  • 3
    In: Journal of Clinical Nursing, February 2012, Vol.21(3‐4), pp.380-387
    Description: To examine the effect of pressure ulcers in older patients on the length of stay in hospital. Previous research on this topic did not focus solely on older people. A growing number of older people require hospital admission. A retrospective observational study. Data of 3198 patients age 75 years and older were included. The setting was a 1350‐bed German University Hospital. Data were drawn from quality indicator data recorded by nurses. The independent effect of pressure ulcers was analysed using a multivariate Poisson–Regression model. Of the participants, 7·1% had an ulcer during their hospitalisation. 87·3% were classified as categories I and II. Mean age was 81·6 years for all patients and 83·2 years for pressure ulcer patients. Pressure ulcer patients had a longer overall hospital stay (19·0 vs. 9·9 days) and a higher excess length of stay (2·6 vs. 0·3 days). Pressure ulcers had a statistically significant effect ( = 0·0011) on the increase in length of stay. The impact of hospital acquired pressure ulcers on length of stay was more pronounced compared to those ulcers being present on admission. The pressure ulcer category was not significant. Pressure ulcers during hospitalisation are an independent and significant predictor of a prolonged inpatient stay for elderly patients. This study indicates that besides complications and co‐morbidities social factors, as well as the hospital’s internal processes of patient care, also can play a significant role. To evaluate the distinct role of hospital acquired pressure ulcers further research is needed. The elderly patients in this study were a heterogeneous group. The implementation of clinical and nursing processes for both the ‘fit’ and the ‘sick’ geriatric patients is an important challenge.
    Keywords: Elderly Patients ; Functional Decline ; Hospital ; Length Of Stay ; Pressure Ulcer
    ISSN: 0962-1067
    E-ISSN: 1365-2702
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  • 4
    Language: English
    In: Marine Biology, 2012, Vol.159(10), pp.2249-2258
    Description: Pop-up satellite archival tags were deployed onto four wahoo during 2006 in the western North Atlantic (~26.5°N, 79.3°W), providing movement, depth, and temperature data collected over a total of 198 days. Straight-line distances between tag deployment and pop-off positions ranged from 162.5 to 1,960.0 km. Wahoo spent 〉90 % of their time in water 〈200 m, and 〉90 % of their time in water between 17.5 and 27.5 °C. Three fish made regular trips to depths 〉200 m. All four fish had significantly different depth distributions between the dark and light periods (Kruskal–Wallace test, p  〈 0.001). The median mean depth for all fish combined was 29.7 m during the dark period (Q1 = 18.8 m, Q3 = 46.2 m) and 50.7 m during the light period (Q1 = 22.3 m, Q3 = 112.3 m). This research improves an otherwise poor understanding of wahoo movements and depth/temperature distributions and suggests potential interactions with other members of the pelagic fish community, many of which are commercially important and either fully or over-exploited.
    Keywords: Wahoo -- Distribution;
    ISSN: 0025-3162
    E-ISSN: 1432-1793
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  • 5
    Language: English
    In: Climatic Change, April, 2013, Vol.117(4), p.613(13)
    Description: Byline: Ole Magnus Theisen (1,2), Nils Petter Gleditsch (1,2), Halvard Buhaug (1,2) Abstract: The world is generally becoming less violent, but the debate on climate change raises the specter of a new source of instability and conflict. In this field, the policy debate is running well ahead of its academic foundation--and sometimes even contrary to the best evidence. Although comparative research on security implications of climate change is rapidly expanding, major gaps in knowledge still exist. Taken together, extant studies provide mostly inconclusive insights, with contradictory or weak demonstrated effects of climate variability and change on armed conflict. This article reviews the empirical literature on short-term climate/environmental change and intrastate conflict, with special attention to possible insecurity consequences of precipitation and temperature anomalies and weather-related natural disasters. Based on this assessment, it outlines priorities for future research in this area. Author Affiliation: (1) Department of Sociology and Political Science, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway (2) Centre for the Study of Civil War (CSCW), Peace Research Institute Oslo (PRIO), P.O. Box 9229 Gronland, 0134, Oslo, Norway Article History: Registration Date: 22/11/2012 Received Date: 06/08/2011 Accepted Date: 21/11/2012 Online Date: 03/01/2013 Article note: Electronic supplementary material The online version of this article (doi: 10.1007/s10584-012-0649-4) contains supplementary material, which is available to authorized users. This article is part of a Special Issue on "Improving the Assessment and Valuation of Climate Change Impacts for Policy and Regulatory Analysis" edited by Alex L. Marten, Kate C. Shouse, and Robert E. Kopp.
    Keywords: Natural Disasters -- Analysis ; Weather -- Analysis ; Rain -- Analysis ; Global Temperature Changes -- Analysis
    ISSN: 0165-0009
    Source: Cengage Learning, Inc.
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  • 6
    Language: English
    In: Sensors & Actuators: B. Chemical, Dec, 2013, Vol.189, p.157(8)
    Description: To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.snb.2013.02.071 Byline: Laurent Davoust (a), Johannes Theisen (b)(a) Abstract: One essential advantage of digital microfluidic systems such as, for instance, drop-based lab-on-a-chips, is a massive parallelization of biochemical functions achieved by moving drops under surface acoustic waves or electrowetting on dielectrics (EWOD). This paper aims at characterizing the evaporation rate of a population of drops in a microsystem. Up to now, and despite its importance for end-users, the evaporation rate of one target drop selected among a population of drops has not been measured. This is essentially due to the difficulty of developing imaging in confined microfluidic drop arrays. In this paper, interferometry together with coplanar electrowetting are proposed as a new (non-imaging) evaporation rate measurement method fully compatible with digital microfluidic systems, and easy to be integrated into closed or open geometries. We investigate the impact on drop evaporation of different arrangements of drops and for different degrees of confinement. Use is made of dual-frequency electrowetting [1]: a classical actuation at a high-frequency (15kHz) allows to set the contact angle equal to 90[degrees] while the low-frequency actuation (100-500Hz) is responsible for the excitation of a perfectly spherical standing capillary wave along the drop surface. By considering natural frequencies of the oscillating drop and its capillary spectrum, it is possible to measure a spectral shift under evaporation. The evaporation law by Picknett and Bexon [2] is found valid even for a matrix of drops. Author Affiliation: (a) Electromagnetic Processing of Materials (EPM) Group, Materials and Processes Science and Engineering Laboratory (SIMAP), Grenoble Institute of Technology (Grenoble INP), 38402 Saint Martin d'Heres, France (b) Laboratory of Geophysical and Industrial Fluid Flows (LEGI), University of Grenoble (UJF), 38041 Grenoble, France
    Keywords: Microfluidics ; Dielectric Materials ; Electromagnetism
    ISSN: 0925-4005
    Source: Cengage Learning, Inc.
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  • 7
    Article
    Article
    BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine
    Language: English
    In: British Journal of Sports Medicine April 2014, Vol.48(7), p.631
    Description: Most running-related injuries (RRI) are attributed to training errors.
    Keywords: Regression Analysis -- Usage ; Runners (Sports) -- Health Aspects ; Runners (Sports) -- Training ; Running -- Influence ; Sports Injuries -- Risk Factors;
    ISSN: 0306-3674
    ISSN: 03063674
    E-ISSN: 1473-0480
    E-ISSN: 14730480
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  • 8
    Language: English
    In: Langmuir : the ACS journal of surfaces and colloids, 10 January 2012, Vol.28(1), pp.1041-8
    Description: This paper addresses a method to estimate the size of a sessile drop and to measure its evaporation kinetics by making use of both Michelson interferometry and coplanar electrowetting. From a high-frequency electrowetting voltage, the contact angle of the sessile droplet is monitored to permanently obtain a half-liquid sphere, thus complying perfectly with the drop evaporation theory based on a constant contact angle (Bexon, R.; Picknett, R. J. Colloid Interface Sci. 1977, 61, 336-350). Low-frequency modulation of the electrowetting actuation is also applied to cause droplet shape oscillations and capillary resonance. Interferometry allows us to measure a time-dependent capillary spectrum and, in particular, the shift in natural frequencies induced by drop evaporation. Consequently, diffusive kinetics of drop evaporation can be properly estimated, as demonstrated. Because of coplanar electrode configuration, our methodology can be integrated in open and covered microsystems, such as digital lab-on-a-chip devices.
    Keywords: Electrochemistry ; Wettability
    ISSN: 07437463
    E-ISSN: 1520-5827
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  • 9
    Language: English
    In: Applied and environmental microbiology, May 2013, Vol.79(10), pp.3171-5
    Description: The genetic identity and cofactor composition of the bacterial tellurate reductase are currently unknown. In this study, we examined the requirement of molybdopterin biosynthesis and molybdate transporter genes for tellurate reduction in Escherichia coli K-12. The results show that mutants deleted of the moaA, moaB, moaE, or mog gene in the molybdopterin biosynthesis pathway lost the ability to reduce tellurate. Deletion of the modB or modC gene in the molybdate transport pathway also resulted in complete loss of tellurate reduction activity. Genetic complementation by the wild-type sequences restored tellurate reduction activity in the mutant strains. These findings provide genetic evidence that tellurate reduction in E. coli involves a molybdoenzyme.
    Keywords: Gene Expression Regulation, Enzymologic ; Coenzymes -- Biosynthesis ; Escherichia Coli K12 -- Enzymology ; Metalloproteins -- Biosynthesis ; Tellurium -- Metabolism
    ISSN: 00992240
    E-ISSN: 1098-5336
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  • 10
    In: Experimental Physiology, March 2012, Vol.97(3), pp.319-324
    Description: This report briefly summarizes the cardiovascular factors that influence exercise physiology and, eventually, sports performance of athletes with a spinal cord injury (SCI). The consequences of an SCI are numerous and concern voluntary muscle function, deep and superficial sensitivity, and autonomic function to a degree determined by the level and completeness of the spinal lesion. Athletes with SCI perform with their upper body, which limits their maximal exercise capacity and puts them at a disadvantage compared with leg exercise in terms of mechanical efficiency and physiological adaptations to exercise. Studies generally find that maximal oxygen consumption and mechanical power output are inversely related to spinal lesion level. Athletes with cervical or dorsal lesions down to Th6 have limited maximal heart rates owing to a lack of sympathetic drive to the heart. Blood redistribution from body areas lacking autonomic control is impaired, thus reducing venous return and limiting cardiac stroke volume during exercise. Thermoregulatory function is affected through a lack of afferent neural feedback and limited efferent vasomotor and sudomotor control below the lesion. Strategies to support venous return and to promote body cooling potentially improve physiological responses and athletic performance, especially in individuals with high lesion levels. The latter are subject to autonomic dysreflexia, a generalized sympathetic vasoconstriction below the lesion resulting from nociceptive stimulations in insensate body regions. Acute episodes induce high blood pressure, may enhance exercise performance and must be treated as a clinical emergency. Deliberate triggering of this reflex is prohibited by the International Paralympic Committee.
    Keywords: Exercise -- Physiological Aspects ; Spinal Cord Injuries -- Physiological Aspects ; Sports Injuries -- Physiological Aspects ; Energy Efficiency -- Physiological Aspects ; Athletes -- Physiological Aspects ; Hypertension -- Physiological Aspects;
    ISSN: 0958-0670
    E-ISSN: 1469-445X
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