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Radiative Heating of an Ice-Free Arctic Ocean
During recent decades, there has been dramatic Arctic sea ice retreat. This has reduced the top-of-atmosphere albedo, adding more solar energy to the climate system. There is substantial uncertainty regarding how much ice retreat and associated solar heating will occur in the future. This is relevant to future climate projections, including the timescale for reaching global warming stabilization targets. Here we use satellite observations to estimate the amount of solar energy that would be added in the worst-case scenario of a complete disappearance of Arctic sea ice throughout the sunlit part of the year. Assuming constant cloudiness, we calculate a global radiative heating of 0.71 W/m2 relative to the 1979 baseline state. This is equivalent to the effect of one trillion tons of CO2 emissions. These results suggest that the additional heating due to complete Arctic sea ice loss would hasten global warming by an estimated 25 years
The reversibility of sea ice loss in a state-of-the-art climate model
Rapid Arctic sea ice retreat has fueled speculation about the possibility of threshold (or ‘tipping point’) behavior and irreversible loss of the sea ice cover. We test sea ice reversibility within a state-of-the-art atmosphere–ocean global climate model by increasing atmospheric carbon dioxide until the Arctic Ocean becomes ice-free throughout the year and subsequently decreasing it until the initial ice cover returns. Evidence for irreversibility in the form of hysteresis outside the envelope of natural variability is explored for the loss of summer and winter ice in both hemispheres. We find no evidence of irreversibility or multiple ice-cover states over the full range of simulated sea ice conditions between the modern climate and that with an annually ice-free Arctic Ocean. Summer sea ice area recovers as hemispheric temperature cools along a trajectory that is indistinguishable from the trajectory of summer sea ice loss, while the recovery of winter ice area appears to be slowed due to the long response times of the ocean near the modern winter ice edge. The results are discussed in the context of previous studies that assess the plausibility of sea ice tipping points by other methods. The findings serve as evidence against the existence of threshold behavior in the summer or winter ice cover in either hemisphere
Penis size: Survey of female perceptions of sexual satisfaction
BACKGROUND: Does the size of the male penis, in terms of length or width, make a difference in female sexual satisfaction? METHOD: To study the effect of penis width vs. length on female sexual satisfaction, 50 sexually active female undergraduate students were asked which felt better, i. e., was penis width or length more important for their sexual satisfaction. RESULTS: None reported they did not know, or that width and length were equally satisfying. A large majority, 45 of 50, reported width was more important (p < .001). CONCLUSION: Implications are discussed, including the fact that the data seem to contradict Masters and Johnson about penis size having no physiological effect on female sexual satisfaction
Creative Interventions to Increase Counselor-in-Training Wellness
Wellness is a broad term that emphasizes a person’s current state of mental, physical, emotional, spiritual, and professional wellness. Professional counseling was built upon the foundations of wellness and practitioner self-care. While counseling programs understand the importance of wellness and counseling ethics emphasize the necessity of professional wellness, students frequently do not feel prepared or trained enough in wellness dimensions. This manuscript provides a rationale for a program wellness model and outlines a proposed series of interventions aimed at increasing students’ understanding, ability to self-assess, and strategies related to self-care and wellness
Heat/mortality sensitivities in Los Angeles during winter: A unique phenomenon in the United States
Background: Extreme heat is often associated with elevated levels of human mortality, particularly across the mid-latitudes. Los Angeles, CA exhibits a unique, highly variable winter climate, with brief periods of intense heat caused by downsloping winds commonly known as Santa Ana winds. The goal is to determine if Los Angeles County is susceptible to heat-related mortality during the winter season. This is the first study to specifically evaluate heat-related mortality during the winter for a U.S. city. Methods: Utilizing the Spatial Synoptic Classification system in Los Angeles County from 1979 through 2010, we first relate daily human mortality to synoptic air mass type during the winter season (December, January, February) using Welch\u27s t-tests. However, this methodology is only somewhat effective at controlling for important inter- and intra-annual trends in human mortality unrelated to heat such as influenza outbreaks. As a result, we use distributed lag nonlinear modeling (DLNM) to evaluate if the relative risk of human mortality increases during higher temperatures in Los Angeles, as the DLNM is more effective at controlling for variability at multiple temporal scales within the human mortality dataset. Results: Significantly higher human mortality is uncovered in winter when dry tropical air is present in Los Angeles, particularly among those 65 years and older (p \u3c 0.001). The DLNM reveals the relative risk of human mortality increases when above average temperatures are present. Results are especially pronounced for maximum and mean temperatures, along with total mortality and those 65 +. Conclusions: The discovery of heat-related mortality in winter is a unique finding in the United States, and we recommend stakeholders consider warning and intervention techniques to mitigate the role of winter heat on human health in the County
An interacting spin flip model for one-dimensional proton conduction
A discrete asymmetric exclusion process (ASEP) is developed to model proton
conduction along one-dimensional water wires. Each lattice site represents a
water molecule that can be in only one of three states; protonated,
left-pointing, and right-pointing. Only a right(left)-pointing water can accept
a proton from its left(right). Results of asymptotic mean field analysis and
Monte-Carlo simulations for the three-species, open boundary exclusion model
are presented and compared. The mean field results for the steady-state proton
current suggest a number of regimes analogous to the low and maximal current
phases found in the single species ASEP [B. Derrida, Physics Reports, {\bf
301}, 65-83, (1998)]. We find that the mean field results are accurate
(compared with lattice Monte-Carlo simulations) only in the certain regimes.
Refinements and extensions including more elaborate forces and pore defects are
also discussed.Comment: 13pp, 6 fig
How do general practitioners experience providing care to refugees with mental health problems? A qualitative study from Denmark
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
The effect of recombinant mast cell growth factor on purified murine hematopoietic stem cells.
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