58 research outputs found
Forecasting the response of Earth\u27s surface to future climatic and land use changes: A review of methods and research needs
In the future, Earth will be warmer, precipitation events will be more extreme, global mean sea level will rise, and many arid and semiarid regions will be drier. Human modifications of landscapes will also occur at an accelerated rate as developed areas increase in size and population density. We now have gridded global forecasts, being continually improved, of the climatic and land use changes (C&LUC) that are likely to occur in the coming decades. However, besides a few exceptions, consensus forecasts do not exist for how these C&LUC will likely impact Earth-surface processes and hazards. In some cases, we have the tools to forecast the geomorphic responses to likely future C&LUC. Fully exploiting these models and utilizing these tools will require close collaboration among Earth-surface scientists and Earth-system modelers. This paper assesses the state-of-the-art tools and data that are being used or could be used to forecast changes in the state of Earth\u27s surface as a result of likely future C&LUC. We also propose strategies for filling key knowledge gaps, emphasizing where additional basic research and/or collaboration across disciplines are necessary. The main body of the paper addresses cross-cutting issues, including the importance of nonlinear/threshold-dominated interactions among topography, vegetation, and sediment transport, as well as the importance of alternate stable states and extreme, rare events for understanding and forecasting Earth-surface response to C&LUC. Five supplements delve into different scales or process zones (global-scale assessments and fluvial, aeolian, glacial/periglacial, and coastal process zones) in detail. © 2015 The Authors. Earth\u27s Future published by Wiley on behalf of the American Geophysical Union
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Entrance channel dependent light-charged particle emission of the {sup 156}Er compound
Light-charged particle decay from the {sup 156}Er compound nucleus, populated by {sup 12}C+{sup 144}Sm and {sup 60}Ni+{sup 96}Zr at the same excitation energy, were measured in coincidence with the evaporation residues. The high energy slope of charged particle spectra for the {sup 60}Ni-induced reaction is steeper than for the {sup 12}C-induced reaction. Model calculations including particle evaporation during compound nucleus formation result in good agreement with the data. This suggests that the difference in the charged particle spectra between the two entrance channels is due to a longer formation time in the {sup 60}Ni-induced reaction. 14 refs., 3 figs
Vaccination with Fendrix of prior nonresponding patients with HIV has a high success rate
Background: Patients with HIV have a poor serological conversion rate with the
standard vaccination strategy against hepatitis B virus (HBV) of around 50%. Vaccination with Fendrix confers much better results in these patients. In this study, we tested
the effect of revaccination with Fendrix in prior nonresponding patients with HIV and
aimed to determine which factors are associated with seroconversion.
Methods: Eight Dutch HIV treatment centers participated in this retrospective study.
Patients infected with HIV-1 and nonresponding to prior course of vaccination against
HBV (anti-HBs <10 IU/ml) and who had Fendrix as a second, third or fourth effort to
achieve seroconversion were eligible for inclusion. Primary outcome was the proportion of patients with seroconversion after revaccination with Fendrix. Univariate binary
logistic regression analyses were used to determine which factors could be used as
predictors for seroconversions.
Results: We included 100 patients with HIV. The mean age was 47.3 (11.0) years and
86% were men. Revaccination with Fendrix showed a seroconversion rate of 81% (95%
confidence interval 72–88%). Median nadir CD4þ cell count was 300 (20–1040) cells/
ml and median CD4þ cell count at the time at starting vaccination with Fendrix was 605
(210–1190) cells/ml. Regression analyses showed no significant factor associated with
seroconversion.
Conclusions: Revaccination with Fendrix of patients prior nonresponding to other
hepatitis B vaccination strategies has a high success rate. Eighty-one percentage
responded with seroconversion, irrespective of CD4þ cell count
Enhanced Fusion-Evaporation Cross Sections in Neutron-Rich Sn on Ni
Evaporation residue cross sections have been measured with neutron-rich
radioactive Sn beams on Ni in the vicinity of the Coulomb
barrier. The average beam intensity was particles per second
and the smallest cross section measured was less than 5 mb. Large subbarrier
fusion enhancement was observed. Coupled-channels calculations taking into
account inelastic excitation and neutron transfer underpredict the measured
cross sections below the barrier.Comment: 4 pages including 1 table and 3 figure
Relations between fusion cross sections and average angular momenta
We study the relations between moments of fusion cross sections and averages
of angular momentum. The role of the centrifugal barrier and the target
deformation in determining the effective barrier radius are clarified. A simple
method for extracting average angular momentum from fusion cross sections is
demonstrated using numerical examples as well as actual data.Comment: 16 REVTeX pages plus 8 included Postscript figures (uses the epsf
macro); submitted to Phys. Rev. C; also available at
http://nucth.physics.wisc.edu/preprint
Lowland river responses to intraplate tectonism and climate forcing quantified with luminescence and cosmogenic 10Be
Non-AIDS defining cancers in the D:A:D Study-time trends and predictors of survival : a cohort study
BACKGROUND:Non-AIDS defining cancers (NADC) are an important cause of morbidity and mortality in HIV-positive individuals. Using data from a large international cohort of HIV-positive individuals, we described the incidence of NADC from 2004-2010, and described subsequent mortality and predictors of these.METHODS:Individuals were followed from 1st January 2004/enrolment in study, until the earliest of a new NADC, 1st February 2010, death or six months after the patient's last visit. Incidence rates were estimated for each year of follow-up, overall and stratified by gender, age and mode of HIV acquisition. Cumulative risk of mortality following NADC diagnosis was summarised using Kaplan-Meier methods, with follow-up for these analyses from the date of NADC diagnosis until the patient's death, 1st February 2010 or 6 months after the patient's last visit. Factors associated with mortality following NADC diagnosis were identified using multivariable Cox proportional hazards regression.RESULTS:Over 176,775 person-years (PY), 880 (2.1%) patients developed a new NADC (incidence: 4.98/1000PY [95% confidence interval 4.65, 5.31]). Over a third of these patients (327, 37.2%) had died by 1st February 2010. Time trends for lung cancer, anal cancer and Hodgkin's lymphoma were broadly consistent. Kaplan-Meier cumulative mortality estimates at 1, 3 and 5 years after NADC diagnosis were 28.2% [95% CI 25.1-31.2], 42.0% [38.2-45.8] and 47.3% [42.4-52.2], respectively. Significant predictors of poorer survival after diagnosis of NADC were lung cancer (compared to other cancer types), male gender, non-white ethnicity, and smoking status. Later year of diagnosis and higher CD4 count at NADC diagnosis were associated with improved survival. The incidence of NADC remained stable over the period 2004-2010 in this large observational cohort.CONCLUSIONS:The prognosis after diagnosis of NADC, in particular lung cancer and disseminated cancer, is poor but has improved somewhat over time. Modifiable risk factors, such as smoking and low CD4 counts, were associated with mortality following a diagnosis of NADC
Effect of Red Blood Cell Storage Age on Outcomes in Non-Hodgkin Lymphoma Patients Receiving Autologous Stem Cell Transplantation
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Experimental fusion excitation functions and derived barrier distributions for heavy ion systems involving prolate and oblate target nuclei
Fusion excitation functions spanning the entire barrier region in 1 MeV energy steps for the two systems {sup 40}Ca + {sup 192}Os, {sup 194}Pt are presented. The results of fission fragment angular distribution measurements for fusion-fission of {sup 40}Ca + {sup 197}Au at several projectile energies within the barrier region are also presented. The fusion data is of high enough precision to allow for extraction of the distribution of fusion barriers from the second differential of the product of E and {sigma}. Basic coupled channels calculations which are in quite good agreement with the data are shown and discussed
Trajectories of risk for early sexual activity and early substance use in the Fast Track prevention program
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