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Incidence and public health burden of sunburn among beachgoers in the United States.
The beach environment creates many barriers to effective sun protection, putting beachgoers at risk for sunburn, a well-established risk factor for skin cancer. Our objective was to estimate incidence of sunburn among beachgoers and evaluate the relationship between sunburn incidence and sun-protective behaviors. A secondary analysis, of prospective cohorts at 12 locations within the U.S. from 2003 to 2009 (n = 75,614), were pooled to evaluate sunburn incidence 10-12 days after the beach visit. Behavioral and environmental conditions were cross-tabulated with sunburn incidence. Multivariable logistic regression was used to estimate the association between new sunburn and sun-protective behaviors. Overall, 13.1% of beachgoers reported sunburn. Those aged 13-18 years (16.5%), whites (16.0%), and those at beach locations along the Eastern Seaboard (16.1%), had the highest incidence of sunburn. For those spending â„5 h in the sun, the use of multiple types of sun protection reduced odds of sunburn by 55% relative to those who used no sun protection (Odds Ratio = 0.45 (95% Confidence Interval:0.27-0.77)) after adjusting for skin type, age, and race. Acute health effects of sunburn tend to be mild and self-limiting, but potential long-term health consequences are more serious and costly. Efforts to encourage and support proper sun-protective behaviors, and increase access to shade, protective clothing, and sunscreen, can help prevent sunburn and reduce skin cancer risk among beachgoers
Widespread Infilling of Tidal Channels and Navigable Waterways in the Human-Modified Tidal Deltaplain of Southwest Bangladesh
Since the 1960s, ~5000 km2 of tidal deltaplain in southwest Bangladesh has been embanked and converted to densely inhabited, agricultural islands (i.e., polders). This landscape is juxtaposed to the adjacent Sundarbans, a pristine mangrove forest, both well connected by a dense network of tidal channels that effectively convey water and sediment throughout the region. The extensive embanking in poldered areas, however, has greatly reduced the tidal prism (i.e., volume of water) transported through local channels. We reveal that \u3e600 km of these major waterways have infilled in recent decades, converting to land through enhanced sedimentation and the direct blocking of waterways by embankments and sluice gates. Nearly all of the observed closures (~98%) have occurred along the embanked polder systems, with no comparable changes occurring in channels of the Sundarbans (2 of new land in the last 40â50 years, the rate of which, ~2 km2/yr, offsets the 4 km2/yr that is eroded at the coast, and is equivalent to ~20% of the new land produced naturally at the Ganges-Brahmaputra tidal rivermouth. Most of this new land, called âkhasâ in Bengali, has been reclaimed for agriculture or aquaculture, contributing to the local economy. However, benefits are tempered by the loss of navigable waterways for commerce, transportation, and fishing, as well as the forced rerouting of tidal waters and sediments necessary to sustain this low-lying landscape against rising sea level. A more sustainable delta will require detailed knowledge of the consequences of these hydrodynamic changes to support more scientifically-grounded management of water, sediment, and tidal energy distribution
Using ground based geophysics to evaluate hydrogeologic effects of subsurface drip irrigation systems used to manage produced water in the Powder River Basin, Wyoming
The U.S Department of Energyâs National Energy Technology Laboratory has been evaluating various geophysical methods for site characterization regarding environmental issues associated with fossil fuels including produced water management. A relatively new method of managing produced water from coal bed natural gas production is through subsurface drip irrigation. This system involves disposing the produced water near the bottom of the root zone in agricultural fields, which would provide a beneficial use of this resource. The focus of this paper is to present results from a pre-injection geophysical survey for site assessment and background data. A pre-construction survey of approximately 1.2 km2 was completed in June 2007 using a Geophex GEM-2 broadband sensor over six fields along the Powder River floodplain. Quality assurance measures included drift checks, duplicate line surveys, and repeat field surveys using the Geometrics OhmMapper instrument. Subsequent surveys will be completed once the system is installed and operational. Geophysical inversion models were completed to provide a detailed cross-section of the subsurface geoelectrical structure along each line. Preliminary interpretations reveal that the subsurface conductivity distribution correlates to geomorphologic features
Early immune anergy towards recall antigens and mitogens in patients at onset of septic shock
The pathology of sepsis is typically characterized by an infection and excessive initial inflammation including a cytokine storm, followed by a state of immune suppression or paralysis. This classical view of a two peak kinetic immune response is currently controversially discussed. This study was a sub-study of the randomized clinical Trial SISPCT registered with www. clinicaltrials. gov (NCT00832039, Registration date: 29/01/2009). Blood samples from 76 patients with severe sepsis and septic shock were incubated for 48 h at 37 degrees C in vitro with bacterial or fungal recall-antigens or specific mitogen antigens within 24 hours of sepsis onset. Recall-antigen stimulation led to a severe dampening of normal cytokine release. This immunologic anergy was similarly observed after mitogen stimulation. Moreover, patients under hydrocortisone therapy or with lowered arterial oxygen tension had further reductions in cytokine levels upon B- and T-cell mitogen stimulation. This investigation reveals an early onset of immunoparalysis during sepsis. This immune incompetence in mounting an adequate response to further infections includes previously sensitized pathogens, as seen with recall- antigens. Also, the immune-suppressive role of hydrocortisone and low PaO2 is highlighted. Aside from early broad-spectrum antimicrobial therapy, our findings reinforce the need for maximal immunological support and protection against further infections at the onset of sepsis
Morphological Instabilities in a growing Yeast Colony: Experiment and Theory
We study the growth of colonies of the yeast Pichia membranaefaciens on
agarose film. The growth conditions are controlled in a setup where nutrients
are supplied through an agarose film suspended over a solution of nutrients. As
the thickness of the agarose film is varied, the morphology of the front of the
colony changes. The growth of the front is modeled by coupling it to a
diffusive field of inhibitory metabolites. Qualitative agreement with
experiments suggests that such a coupling is responsible for the observed
instability of the front.Comment: RevTex, 4 pages and 3 figure
Novel non-equilibrium critical behavior in unidirectionally coupled stochastic processes
Phase transitions from an active into an absorbing, inactive state are
generically described by the critical exponents of directed percolation (DP),
with upper critical dimension d_c = 4. In the framework of single-species
reaction-diffusion systems, this universality class is realized by the combined
processes A -> A + A, A + A -> A, and A -> \emptyset. We study a hierarchy of
such DP processes for particle species A, B,..., unidirectionally coupled via
the reactions A -> B, ... (with rates \mu_{AB}, ...). When the DP critical
points at all levels coincide, multicritical behavior emerges, with density
exponents \beta_i which are markedly reduced at each hierarchy level i >= 2.
This scenario can be understood on the basis of the mean-field rate equations,
which yield \beta_i = 1/2^{i-1} at the multicritical point. We then include
fluctuations by using field-theoretic renormalization group techniques in d =
4-\epsilon dimensions. In the active phase, we calculate the fluctuation
correction to the density exponent for the second hierarchy level, \beta_2 =
1/2 - \epsilon/8 + O(\epsilon^2). Monte Carlo simulations are then employed to
determine the values for the new scaling exponents in dimensions d<= 3,
including the critical initial slip exponent. Our theory is connected to
certain classes of growth processes and to certain cellular automata, as well
as to unidirectionally coupled pair annihilation processes. We also discuss
some technical and conceptual problems of the loop expansion and their possible
interpretation.Comment: 29 pages, 19 figures, revtex, 2 columns, revised Jan 1995: minor
changes and additions; accepted for publication in Phys. Rev.
Repetition-to-Repetition Differences Using Cluster and Accentuated Eccentric Loading in the Back Squat
The current investigation was an examination of the repetition-to-repetition magnitudes and changes in kinetic and kinematic characteristics of the back squat using accentuated eccentric loading (AEL) and cluster sets. Trained male subjects (age = 26.1 ± 4.1 years, height = 183.5 ± 4.3 cm, body mass = 92.5 ± 10.5 kg, back squat to body mass ratio = 1.8 ± 0.3) completed four load condition sessions, each consisting of three sets of five repetitions of either traditionally loaded straight sets (TL), traditionally loaded cluster sets (TLC), AEL cluster sets (AEC), and AEL straight sets where only the initial repetition had eccentric overload (AEL1). Eccentric overload was applied using weight releasers, creating a total eccentric load equivalent to 105% of concentric one repetition maximum (1RM). Concentric load was 80% 1RM for all load conditions. Using straight sets (TL and AEL1) tended to decrease peak power (PP) (d = â1.90 to â0.76), concentric rate of force development (RFDCON) (d = â1.59 to â0.27), and average velocity (MV) (d = â3.91 to â1.29), with moderate decreases in MV using cluster sets (d = â0.81 to â0.62). Greater magnitude eccentric rate of force development (RFDECC) was observed using AEC at repetition three (R3) and five (R5) compared to all load conditions (d = 0.21â»0.65). Large within-condition changes in RFDECC from repetition one to repetition three (âREP1â»3) were present using AEL1 (d = 1.51), demonstrating that RFDECC remained elevated for at least three repetitions despite overload only present on the initial repetition. Overall, cluster sets appear to permit higher magnitude and improved maintenance of concentric outputs throughout a set. Eccentric overload with the loading protocol used in the current study does not appear to potentiate concentric output regardless of set configuration but may cause greater RFDECC compared to traditional loading
Multiple relativistic outbursts of GRS 1915+105: radio emission and internal shocks
We present 5-GHz MERLIN radio images of the microquasar GRS 1915+105 during
two separate outbursts in 2001 March and 2001 July, following the evolution of
the jet components as they move outwards from the core of the system. Proper
motions constrain the intrinsic jet speed to be >0.57c, but the uncertainty in
the source distance prevents an accurate determination of the jet speed. No
deceleration is observed in the jet components out to an angular separation of
about 300mas. Linear polarisation is observed in the approaching jet component,
with a gradual rotation in position angle and a decreasing fractional
polarisation with time. Our data lend support to the internal shock model
whereby the jet velocity increases leading to internal shocks in the
pre-existing outflow before the jet switches off. The compact nuclear jet is
seen to re-establish itself within two days, and is visible as core emission at
all epochs. The energetics of the source are calculated for the possible range
of distances; a minimum power of 1-10 per cent of the Eddington luminosity is
required to launch the jet.Comment: 18 pages, 14 figures, accepted for publication in MNRAS. For
higher-resolution versions of Figures 3, 5, and 12, see
http://remote.science.uva.nl/~jmiller/grs1915/figures.htm
WFPC2 Observations of Compact Star Cluster Nuclei in Low Luminosity Spiral Galaxies
We have used the Wide Field Planetary Camera 2 aboard the Hubble Space
Telescope to image the compact star cluster nuclei of the nearby, late-type,
low-luminosity spiral galaxies NGC 4395, NGC 4242, and ESO 359-029. We also
analyze archival WFPC2 observations of the compact star cluster nucleus of M33.
A comparative analysis of the structural and photometric properties of these
four nuclei is presented. All of the nuclei are very compact, with luminosity
densities increasing at small radii to the resolution limit of our data. NGC
4395 contains a Seyfert 1 nucleus with a distinct bipolar structure and bright
associated filaments which are likely due to [OIII] emission. The M33 nucleus
has a complex structure, with elongated isophotes and possible signatures of
weak activity, including a jet-like component. The other two nuclei are not
known to be active, but share similar physical size scales and luminosities to
the M33 and NGC 4395 nuclei. The circumnuclear environments of all four of our
program galaxies are extremely diffuse, have only low-to-moderate star
formation, and appear to be devoid of large quantities of dust. The central
gravitational potentials of the galaxies are also quite shallow, making the
origin of these types of `naked' nuclei problematic.Comment: to appear in the July 1999 Astronomical Journal; 38 pages (Latex), 5
tables (postscript), 21 figures (gif); postscript versions of the figures may
be obtained via anonymous ftp at
ftp://ftp.cv.nrao.edu/NRAO-staff/lmatthew/lanl-nucle
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