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The super greenhouse effect in a changing climate
In all outputs of the 1%/yr increase inCO2 climate model experiments archived under the World Climate
Research Programmeâs (WCRP) phase 5 of the Coupled Model Intercomparison Project (CMIP5), regions
exist in the low latitudes where both the clear-sky and all-sky OLR decrease with surface warming. These are
identified as regions of positive longwave feedback and are regions of a super greenhouse effect (SGE). These
SGE regions are identified from feedback analysis of the 4X CO2 abrupt experiments of CMIP5, and despite
their existence, there is little agreement across models as to the magnitude of the effect. The general effects of
clouds on the SGE are to amplify the clear-sky SGE, but there is also poor agreement on the magnitude of the
amplification that varies by an order of magnitude across models. Sensitivity analyses indicate that localized
SGE regions are spatially aligned with a large moistening of the upper troposphere. The reduction in clear-sky
OLR arises from a reduction in emission in the far IR with nonnegligible contributions from mid-IR emission
from the midtroposphere. When viewed in the broader context of meridional heat transport, it is found that of
the 1.03-PW rate of heat gained globally, 0.8 PW is absorbed in the tropics and is contributed almost equally
by reductions in clear-sky longwave emission (i.e., the clear-sky SGE) and increased absorbed clear-sky solar
radiation associated with increased water vapor. The processes that define the clear-sky SGE are shown to be
fundamental to the way models accumulate heat and then transport it poleward
Ventricular tachycardia in infants with structurally normal heart: A benign disorder
We evaluated the presentation, treatment, and outcome of infants who present with ventricular tachycardia in the first year of life. Seventy-six infants were admitted to our institution with a diagnosis of ventricular tachycardia between January, 1987 and May, 2006. Forty-five infants were excluded from the study because of additional confounding diagnoses including accelerated idioventricular rhythm, Wolffâ ParkinsonâWhite syndrome, supraventricular tachycardia with aberrancy, long QT syndrome, cardiac rhabdomyoma, myocarditis, congenital lesions, or incomplete data. The remaining 31 included infants who had a median age at presentation of 1 day, with a range from 1 to 255 days, and a mean ventricular tachycardia rate of 213 beats per minute, with a range from 171 to 280, at presentation. The infants were treated chronically with propranolol (38.7%), amiodarone (12.9%), mexiletine (3.2%), propranolol and mexiletine (9.7%), or propranolol and procainamide (6.5%). The median duration of treatment was 13 months, with a range from 3 to 105 months. Ventricular tachycardia resolved spontaneously in all infants. No patient died, or received catheter ablation or device therapy. Median age at last ventricular tachycardia was 59 days, with a range from 1 to 836 days. Mean follow-up was 45 months, with a range from 5 to 164 months, with a mean ventricular tachycardia-free period of 40 months. Infants with asymptomatic ventricular tachycardia, a structurally normal heart, and no additional electrophysiological diagnosis all had spontaneous resolution of tachycardia. Furthermore, log-rank analysis of the time to ventricular tachycardia resolution showed no difference between children who received chronic outpatient anti-arrhythmic treatment and those who had no such therapy. While indications for therapy cannot be determined from this study, lack of symptoms or myocardial dysfunction suggests that therapy may not be necessary
Impact of age and race on outcomes of a program to prevent excess weight gain and disordered eating in adolescent girls
Interpersonal psychotherapy (IPT) prevents weight gain and reduces loss-of-control (LOC)-eating in adults. However, IPT was not superior to health-education (HE) for preventing excess weight gain and reducing LOC-eating over 1-year in adolescent girls at risk for excess weight gain and eating disorders. Limited data suggest that older and non-White youth may be especially responsive to IPT. In secondary analyses, we examined if age or race moderated weight and LOC-eating outcomes. The 113 participants (12â17 years; 56.6% White) from the original trial were re-contacted 3 years later for assessment. At baseline and follow-up visits through 3 years, we assessed BMI, adiposity by dual energy X-ray absorptiometry, and LOC-eating presence. In linear mixed models, baseline age moderated 3-year BMI outcome; older girls in IPT had the lowest 3-year BMI gain compared to younger girls in IPT and all girls in HE, p = 0.04. A similar pattern was observed for adiposity. Race moderated 3-year LOC-eating; non-White girls in IPT were most likely to abstain from LOC-eating at 3 years compared to all other girls, p = 0.04. This hypothesis-generating analysis suggests future studies should determine if IPT is especially efficacious at reducing LOC-eating in older, non-White adolescents
Attachment, Social Support, and Perceived Mental Health of Adult Dog Walkers: What Does Age Have to Do With It?
In part of a larger pilot study of dog walking as a physical activity intervention we assessed levels of attachment, social supports, and perceived mental health of 75 dog owners, identified through a tertiary- care veterinary hospital. Owners completed the Medical Outcomes Study (MOS) Social Support Survey, mental health component of the Short-Form-12 (SF-12) Health Survey, and the Lexington Attachment to Pets Scale (LAPS). Of particular interest was that younger owners had stronger attachments to their dogs (r = -.488;p \u3c.001) and less social support (r = .269;p =.021). Our study suggests the importance of companion animals for social support, particularly for those without close friends/relatives. For younger owners, our study reveals vulnerabilities in support networks that may warrant referrals to human helping professionals. We suggest the use of Carstensen\u27s Socioemotional Selectivity Theory as an interpretive framework to underscore the importance of including companion animals as part of the human social convoy, especially in terms of providing affectionate and interactional social support
Production of a long-term global water vapor and liquid water data set using ultra-fast methods to assimilate multi-satellite and radiosonde observations
There is a well-documented requirement for a comprehensive and accurate global moisture data set to assist many important studies in atmospheric science. Currently, atmospheric water vapor measurements are made from a variety of sources including radiosondes, aircraft and surface observations, and in recent years, by various satellite instruments. Creating a global data set from a single measuring system produces results that are useful and accurate only in specific situations and/or areas. Therefore, an accurate global moisture data set has been derived from a combination of these measurement systems. Under a NASA peer-reviewed contract, STC-METSAT produced two 5-yr (1988-1992) global data sets. One is the total column (integrated) water vapor data set and the other, a global layered water vapor data set using a combination of radiosonde observations, Television and Infrared Observation Satellite (TIROS) Operational Satellite (TOVS), and Special Sensor Microwave/Imager (SSM/I) data sets. STC-METSAT also produced a companion, global, integrated liquid water data set. The complete data set (all three products) has been named NVAP, an anachronym for NASA Water Vapor Project. STC-METSAT developed methods to process the data at a daily time scale and 1 x 1 deg spatial resolution
Production of long-term global water vapor and liquid water data set using ultra-fast methods to assimilate multi-satellite and radiosonde observations
In recent years climate research scientists have recognized the need for increased time and space resolution precipitable and liquid water data sets. This project is designed to meet those needs. Specifically, NASA is funding STC-METSAT to develop a total integrated column and layered precipitable water data set. This is complemented by a total column liquid water data set. These data are global in extent, 1 deg x 1 deg in resolution, with daily grids produced. Precipitable water is measured by a combination of in situ radiosonde observations and satellite derived infrared and microwave retrievals from four satellites. This project combines these data into a coherent merged product for use in global climate research. This report is the Year 2 Annual Report from this NASA-sponsored project and includes progress-to-date on the assigned tasks
Production of long-term global water vapor and liquid water data set using ultra-fast methods to assimilate multi-satellite and radiosonde observations
During the next decade, many programs and experiments under the Global Energy and Water Cycle Experiment (GEWEX) will utilize present day and future data sets to improve our understanding of the role of moisture in climate, and its interaction with other variables such as clouds and radiation. An important element of GEWEX will be the GEWEX Water Vapor Project (GVaP), which will eventually initiate a routine, real-time assimilation of the highest quality, global water vapor data sets including information gained from future data collection systems, both ground and space based. The comprehensive global water vapor data set being produced by METSAT Inc. uses a combination of ground-based radiosonde data, and infrared and microwave satellite retrievals. This data is needed to provide the desired foundation from which future GEWEX-related research, such as GVaP, can build. The first year of this project was designed to use a combination of the best available atmospheric moisture data including: radiosonde (balloon/acft/rocket), HIRS/MSU (TOVS) retrievals, and SSM/I retrievals, to produce a one-year, global, high resolution data set of integrated column water vapor (precipitable water) with a horizontal resolution of 1 degree, and a temporal resolution of one day. The time period of this pilot product was to be det3ermined by the availability of all the input data sets. January 1988 through December 1988 were selected. In addition, a sample of vertically integrated liquid water content (LWC) was to be produced with the same temporal and spatial parameters. This sample was to be produced over ocean areas only. Three main steps are followed to produce a merged water vapor and liquid water product. Input data from Radiosondes, TOVS, and SSMI/I is quality checked in steps one and two. Processing is done in step two to generate individual total column water vapor and liquid water data sets. The third step, and final processing task, involves merging the individual output products to produce the integrated water vapor product. A final quality control is applied to the merged data sets
Protofibrillar amyloid beta modulation of recombinant hCaV2.2 (N-type) voltage-gated channels
Cav2.2 channels are key regulators of presynaptic Ca2+ influx and their dysfunction and/or aber-rant regulation has been implicated in many disease states; however, the nature of their involve-ment in Alzheimerâs disease (AD) is less clear. In this short communication, we show that recombinant hCav2.2/beta1b/a2d channels are modulated by human synthetic AD-related protofibrillar amyloid beta Abeta1-42 peptide. Structural studies revealed a time-dependent increase in protofibril length, with the majority of protofibrils less than 100nm at 24hr; while at 48 hr, the majority were longer than 100nm. Cav2.2 modulation by Abeta1-42 was different between a âlowâ (100nM) and âhighâ (1”M) concentration in terms of distinct effects on individual biophysical parameters. 100nM Abeta1-42 caused a significant change in the slope factor (k) consistent with improved voltage sensitivity of the channel; by contrast, 1”M Abeta1-42 caused an inhibitory decrease in current density (pA/pF) and maximum conductance (Gmax). These data highlight a differential modulation of Cav2.2 channels by Abeta1-42 peptide. Discrete changes in presynaptic Ca2+ flux have been reported to occur at an early stage of AD; therefore, this study has implications for targeting Cav2.2 in the AD pathology and reveals a potential mechanistic link between amyloid accumulation and Cav2.2 channel modulation
Association between an Internet-Based Measure of Area Racism and Black Mortality
Racial disparities in health are well-documented and represent a significant public health concern in the US. Racism-related factors contribute to poorer health and higher mortality rates among Blacks compared to other racial groups. However, methods to measure racism and monitor its associations with health at the population-level have remained elusive. In this study, we investigated the utility of a previously developed Internet search-based proxy of area racism as a predictor of Black mortality rates. Area racism was the proportion of Google searches containing the âN-wordâ in 196 designated market areas (DMAs). Negative binomial regression models were specified taking into account individual age, sex, year of death, and Census region and adjusted to the 2000 US standard population to examine the association between area racism and Black mortality rates, which were derived from death certificates and mid-year population counts collated by the National Center for Health Statistics (2004â2009). DMAs characterized by a one standard deviation greater level of area racism were associated with an 8.2% increase in the all-cause Black mortality rate, equivalent to over 30,000 deaths annually. The magnitude of this effect was attenuated to 5.7% after adjustment for DMA-level demographic and Black socioeconomic covariates. A model controlling for the White mortality rate was used to further adjust for unmeasured confounders that influence mortality overall in a geographic area, and to examine Black-White disparities in the mortality rate. Area racism remained significantly associated with the all-cause Black mortality rate (mortality rate ratio = 1.036; 95% confidence interval = 1.015, 1.057; p = 0.001). Models further examining cause-specific Black mortality rates revealed significant associations with heart disease, cancer, and stroke. These findings are congruent with studies documenting the deleterious impact of racism on health among Blacks. Our study contributes to evidence that racism shapes patterns in mortality and generates racial disparities in health
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