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Electrifying Integration: Electricity Production and the South-East Europe Regional Energy Market
Initial subjective load carriage injury data collected by interviews and questionnaires
This study aimed to identify the types, incidence, and causes of any potential load carriage injuries or discomfort as a result of a 2-hour, forced-speed, treadmill march carrying 20 kg. Subjective load carriage data were collected, through both interviews and questionnaires, from relatively inexperienced soldiers after a period of load carriage. Results from the study showed that the upper limb is very susceptible to short-term discomfort, whereas the lower limb is not. The shoulders were rated significantly more uncomfortable then any other region, and blisters were experienced by âŒ60% of participants. Shoulder discomfort commences almost as soon as the load is added and increases steadily with time; however, foot discomfort increases more rapidly once the discomfort materializes. In conclusion, early development of shoulder pain or blisters may be a risk factor for severe pain or noncompletion of a period of prolonged load carriage
The effect of military load carriage on ground reaction forces
Load carriage is an inevitable part of military life both during training and operations. Loads carried are frequently as high as 60% bodyweight, and this increases injury risk. In the military, load is carried in a backpack (also referred to as a Bergen) and webbing, these combined form a load carriage system (LCS). A substantial body of literature exists recording the physiological effects of load carriage; less is available regarding the biomechanics. Previous biomechanical studies have generally been restricted to loads of 20% and 40% of bodyweight, usually carried in the backpack alone. The effect of rifle carriage on gait has also received little or no attention in the published literature. This is despite military personnel almost always carrying a rifle during load carriage. In this study, 15 male participants completed 8 conditions: military boot, rifle, webbing 8 and 16 kg, backpack 16 kg and LCS 24, 32 and 40 kg. Results showed that load added in 8 kg increments elicited a proportional increase in vertical and anteroposterior ground reaction force (GRF) parameters. Rifle carriage significantly increased the impact peak and mediolateral impulse compared to the boot condition. These effects may be the result of changes to the vertical and horizontal position of the body's centre of mass, caused by the restriction of natural arm swing patterns. Increased GRFs, particularly in the vertical axis, have been positively linked to overuse injuries. Therefore, the biomechanical analysis of load carriage is important in aiding our understanding of injuries associated with military load carriage
Sociocultural Risk Factors for Elevated Perceived Stress among African American Smokers
Introduction: African Americans experience unique stressors that may inhibit smoking cessation and enhance relapse rates. Few studies, however, have focused on risk factors for perceived stress among treatment seekers. Because African Americans are less likely to quit compared to the larger community, understanding factors associated with perceived stress among smokers has the potential to improve intervention outcomes. This study examined psychosocial and cultural correlates of stress in a sample of African American participants in a randomized controlled trial.
Methods: At baseline, participants reported demographic factors and completed assessments of smoking history, alcohol use, friend and household smoking, weight concerns, acculturation, depressive symptoms, and perceived stress (N = 325). Bivariate associations were examined, followed by multiple regression analyses to test independent relationships. The sample was comprised of mostly middle-aged males, with at least a high school education, who were single, and reported low household income. Participants were moderately nicotine dependent and smoked 18 cigarettes per day for 26 years.
Results: Perceived stress was inversely associated with age (r = -.16, p = .004), education (r = -.11, p = .04), household income (r = -.11, p = .047), and positively associated with being male (r = .13, p = .02). Stress perceptions were positively related to cigarettes per day (r = .11, p = .049), nicotine dependence (r = .20, p = .001), drinking frequency (r = .15, p = .008), drinking intensity (r = .14, p=.02), and inversely related to smoking duration (r = -.12, p = .03). We found positive associations between perceived stress and household smokers (r = .18, p = .004), and friends who smoke (r = .15, p = .01).
Perceived stress was also positively associated with post-cessation weight concern (r = .14, p = .01), a traditional African American cultural orientation; r = .12, p = .04), and depressive symptoms (r = .65, p
Conclusion: These findings have important intervention implications. Many of the risk factors for distress among African American smokers are modifiable. Interventions should prioritize addressing depression, household smoking environment, and stress among younger smokers, in addition to managing other stress-enhancing concerns like alcohol use
Off-duty activity equipment and facilities for advanced spacecraft /preliminary design/
Off-duty activity equipment and facilities preliminary design for advanced spacecraf
Strategies for Determining the Nature of Dark Matter
In this review, we discuss the role of the various experimental programs
taking part in the broader effort to identify the particle nature of dark
matter. In particular, we focus on electroweak scale dark matter particles and
discuss a wide range of search strategies being carried out and developed to
detect them. These efforts include direct detection experiments, which attempt
to observe the elastic scattering of dark matter particles with nuclei,
indirect detection experiments, which search for photons, antimatter and
neutrinos produced as a result of dark matter annihilations, and collider
searches for new TeV-scale physics. Each of these techniques could potentially
provide a different and complementary set of information related to the mass,
interactions and distribution of dark matter. Ultimately, it is hoped that
these many different tools will be used together to conclusively identify the
particle or particles that constitute the dark matter of our universe.Comment: 25 pages, 5 figures, Review intended for the Annual Review of Nuclear
and Particle Scienc
Probing Exotic Physics With Cosmic Neutrinos
Traditionally, collider experiments have been the primary tool used in
searching for particle physics beyond the Standard Model. In this talk, I will
discuss alternative approaches for exploring exotic physics scenarios using
high energy and ultra-high energy cosmic neutrinos. Such neutrinos can be used
to study interactions at energies higher, and over baselines longer, than those
accessible to colliders. In this way, neutrino astronomy can provide a window
into fundamental physics which is highly complementary to collider techniques.
I will discuss the role of neutrino astronomy in fundamental physics,
considering the use of such techniques in studying several specific scenarios
including low scale gravity models, Standard Model electroweak instanton
induced interactions, decaying neutrinos and quantum decoherence.Comment: 11 pages, 6 figures; For the proceedings of From Colliders To Cosmic
Rays, Prague, Czech Republic, September 7-13, 200
Dark Matter and Collider Phenomenology with two light Supersymmetric Higgs Bosons
Recently, it has been pointed out that two different excesses of events
observed at LEP could be interpreted as the CP-even Higgs bosons of the MSSM
with masses of approximately 98 and 114 GeV. If this is the case, the entire
MSSM Higgs sector is required to be light. In this article, we explore such a
scenario in detail. We constrain the Higgs and supersymmetric spectrum using
physics constraints as well as the magnetic moment of the muon. We then
point out the implications for neutralino dark matter -- next generation direct
detection experiments will be sensitive to all MSSM models with such a Higgs
sector. Finally, we find that all models outside of a very narrow corridor of
the parameter space have a charged Higgs boson which will be observed at the
LHC. In those exceptional models which do not contain an observable charged
Higgs, a light top squark will always be seen at the LHC, and likely at the
Tevatron.Comment: 12 pages, 18 figure
Towards low-latency real-time detection of gravitational waves from compact binary coalescences in the era of advanced detectors
Electromagnetic (EM) follow-up observations of gravitational wave (GW) events
will help shed light on the nature of the sources, and more can be learned if
the EM follow-ups can start as soon as the GW event becomes observable. In this
paper, we propose a computationally efficient time-domain algorithm capable of
detecting gravitational waves (GWs) from coalescing binaries of compact objects
with nearly zero time delay. In case when the signal is strong enough, our
algorithm also has the flexibility to trigger EM observation before the merger.
The key to the efficiency of our algorithm arises from the use of chains of
so-called Infinite Impulse Response (IIR) filters, which filter time-series
data recursively. Computational cost is further reduced by a template
interpolation technique that requires filtering to be done only for a much
coarser template bank than otherwise required to sufficiently recover optimal
signal-to-noise ratio. Towards future detectors with sensitivity extending to
lower frequencies, our algorithm's computational cost is shown to increase
rather insignificantly compared to the conventional time-domain correlation
method. Moreover, at latencies of less than hundreds to thousands of seconds,
this method is expected to be computationally more efficient than the
straightforward frequency-domain method.Comment: 19 pages, 6 figures, for PR
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