We analyze a mini ensemble of regional climate projections over the CORDEX Africa domain carried out with RegCM4 model as part of the Phase I CREMA experiment (Giorgi 2013). RegCM4 is driven by the ...HadGEM2-ES and MPI-ESM global models for the RCP8.5 and RCP4.5 greenhouse gas and aerosol concentration scenarios. The focus of the analysis is on seasonal and intraseasonal monsoon characteristics. We find two prominent change signals. Over West Africa and the Sahel MPI produces a forward shift in the monsoon season in line with previous findings, and this shift is also simulated by the RegCM4. Furthermore, the regional model produces a widespread decrease of monsoon precipitation (when driven by both MPI and HadGEM) associated with decreased easterly wave activity in the 6–9 days regime and with soil moisture-precipitation interactions. South of the equator we find an extension of the dry season with delayed onset and anticipated recession of the monsoon and a narrowing and strengthening of the ITCZ precipitation band. This signal is consistent in all global and regional model projections, although with different spatial detail. We plan to enlarge this mini-ensemble as a further contribution to the CORDEX project to better assess the robustness of the signals found in this paper.
Brain cells are immersed in a complex structure forming the extracellular matrix. The composition of the matrix gradually matures during postnatal development, as the brain circuitry reaches its ...adult form. The fully developed extracellular environment stabilizes neuronal connectivity and decreases cortical plasticity as highlighted by the demonstration that treatments degrading the matrix are able to restore synaptic plasticity in the adult brain. The mechanisms through which the matrix inhibits cortical plasticity are not fully clarified. Here we show that a prominent component of the matrix, chondroitin sulfate proteoglycans (CSPGs), restrains morphological changes of dendritic spines in the visual cortex of adult mice. By means of in vivo and in vitro two-photon imaging and electrophysiology, we find that after enzymatic digestion of CSPGs, cortical spines become more motile and express a larger degree of structural and functional plasticity.
A new version of the RegCM regional climate modeling system, RegCM4, has been recently developed and made available for public use. Compared to previous versions, RegCM4 includes new land surface, ...planetary boundary layer, and air–sea flux schemes, a mixed convection and tropical band configuration, modifications to the pre-existing radiative transfer and boundary layer schemes, and a full upgrade of the model code towards improved flexibility, portability, and user friendliness. The model can be interactively coupled to a 1D lake model, a simplified aerosol scheme (including organic carbon, black carbon, SO₄, dust, and sea spray), and a gas phase chemistry module (CBM-Z). After a general description of the model, a series of test experiments are presented over 4 domains prescribed under the CORDEX framework (Africa, South America, East Asia, and Europe) to provide illustrative examples of the model behavior and sensitivities under different climatic regimes. These experiments indicate that, overall, RegCM4 shows an improved performance in several respects compared to previous versions, although further testing by the user community is needed to fully explore its sensitivities and range of applications.
We analyze a transient climate change simulation for the 21st century (1980–2100) over a large all‐Africa domain carried out with the RegCM3 regional model driven by the ECHAM5 global model. We focus ...the analysis on a comparison between the driving and nested model runs. For present climate, the two models show temperature and precipitation biases of similar magnitude but different spatial patterns. In particular the bias patterns in the regional model driven by ECHAM5 are more similar to those of a regional simulation driven by ERA Interim reanalysis fields than to the bias patterns in the present climate simulation by ECHAM5 itself. In the transient simulation, while the temperature changes are strongly driven by the global model, the precipitation change patterns are more different between the global and regional models, particularly over the West Africa and Sahel regions. A targeted analysis suggests that this is due to the different simulation by the two models of the local response to El Niño–Southern Oscillation forcing and of local soil moisture/precipitation feedbacks. Our results thus indicate that local processes and internal model physics and characteristics are important elements in determining the precipitation change signal simulated by the nested regional model in this large domain experiment, especially over equatorial and tropical regions. This adds an element of uncertainty that needs to be address through the use of ensembles of regional model experiments as planned in the Coordinated Regional Climate Downscaling Experiment (CORDEX) project.
Key Points
For present climate the models show rainfall biases with different spatial patterns
The precipitation change patterns are more different over West Africa and Sahel
Differences due to local response to ENSO forcing and soil moisture/precipitation
Because of their dependence on water, natural and human systems are highly sensitive to changes in the hydrologic cycle. The authors introduce a new measure of hydroclimatic intensity (HY-INT), which ...integrates metrics of precipitation intensity and dry spell length, viewing the response of these two metrics to global warming as deeply interconnected. Using a suite of global and regional climate model experiments, it is found that increasing HY-INT is a consistent and ubiquitous signature of twenty-first-century, greenhouse gas–induced global warming. Depending on the region, the increase in HY-INT is due to an increase in precipitation intensity, dry spell length, or both. Late twentieth-century observations also exhibit dominant positive HY-INT trends, providing a hydroclimatic signature of late twentieth-century warming. The authors find that increasing HY-INT is physically consistent with the response of both precipitation intensity and dry spell length to global warming. Precipitation intensity increases because of increased atmospheric water holding capacity. However, increases in mean precipitation are tied to increases in surface evaporation rates, which are lower than for atmospheric moisture. This leads to a reduction in the number of wet days and an increase in dry spell length. This analysis identifies increasing hydroclimatic intensity as a robust integrated response to global warming, implying increasing risks for systems that are sensitive to wet and dry extremes and providing a potential target for detection and attribution of hydroclimatic changes.
On July 1.sup.st, 2021, the University of Colorado Hospital (UCH) implemented new sedation protocols in the luminal gastrointestinal (GI) suite. GI proceduralist supervised, Nurse Administered ...Sedation with fentanyl, midazolam, and diphenhydramine (NAS) sedation was transitioned to Monitored Anesthesia Care with propofol under physician anesthesiologist supervision (MAC). To determine if there are statistically significant reductions in Sedation-Start to Scope-In time (SSSI) when using Monitored Anesthesia Care with propofol (MAC) versus Nurse Administered Sedation with fentanyl, midazolam, and diphenhydramine (NAS). Secondary objectives were to determine if statistically significant improvements to other operational times, quality measures, and satisfaction metrics were present. This study was a retrospective analysis of a natural experiment resultant of a change from NAS to MAC sedation protocols. Outcomes for NAS protocols from 1/1/21-6/30/21 were compared to outcomes of MAC protocols from the dates 8/1/21-10/31/21. Results were analyzed using Quasi-Poisson regression analysis and stratified based on upper GI, lower GI, and combined procedures. Patient demographic data including age, biological sex, comorbidities, and BMI, were adjusted for in the analysis. ASA matching was not performed as nursing sedation does not use ASA classifications. Pre-anesthesia co-morbidities were assessed via evaluation of a strict set of comorbidities abstracted from the electronic medical record. Perioperative operational outcomes include Sedation Start to Scope-In (SSSI), In-Room to Scope-In Time (IRSI), Scope Out to Out of Room (SOOR), Total Case Length (TCL), and Post Anesthesia Care Unit Length of Stay (PACU LOS). Quality outcomes include PACU Administered Medications (PAM), and Clinician Satisfaction Scores (CSS). A total of 5,582 gastrointestinal (GI) endoscopic cases (upper, lower, and combined endoscopies) were observed. Statistically significant decreases in SSSI of 2.5, 2.1, and 2.2 minutes for upper, lower, and dual GI procedures were observed when using MAC protocols. A statistically significant increase in satisfaction scores of 47.0 and 19.6 points were observed for nurses and proceduralists, respectively, when using MAC. MAC protocols for endoscopic GI procedures at UCH led to statistically significant decreases in the time required to complete procedures thus increasing operational efficiency.
This study examines the ability of the latest version of the International Centre for Theoretical Physics (ICTP) regional climate model (RegCM3) to reproduce seasonal mean climatologies, annual cycle ...and interannual variability over the entire African continent and different climate subregions. The new European Center for Medium Range Weather Forecast (ECMWF) ERA-interim reanalysis is used to provide initial and lateral boundary conditions for the RegCM3 simulation. Seasonal mean values of zonal wind profile, temperature, precipitation and associated low level circulations are shown to be realistically simulated, although the regional model still shows some deficiencies. The West Africa monsoon flow is somewhat overestimated and the Africa Easterly Jet (AEJ) core intensity is underestimated. Despite these biases, there is a marked improvement in these simulated model variables compared to previous applications of this model over Africa. The mean annual cycle of precipitation, including single and multiple rainy seasons, is well captured over most African subregions, in some cases even improving the quality of the ERA-interim reanalysis. Similarly, the observed precipitation interannual variability is well reproduced by the regional model over most regions, mostly following, and sometimes improving, the quality of the ERA-interim reanalysis. It is assessed that the performance of this model over the entire African domain is of sufficient quality for application to the study of climate change and climate variability over the African continent.
German philosopher and social critic Theodor Adorno (1903--1969) is widely regarded as one of the twentieth century's most influential thinkers. A leading member of the Frankfurt School, Adorno ...advanced an unconventional type of Marxist analysis in books such asDialectic of Enlightenment(1944),Minima Moralia(1951), andNegative Dialectics(1966). Forced out of Nazi Germany because of his Jewish heritage, Adorno lived in exile in the United States for nearly fifteen years. InAdorno and Democracy,Shannon Mariotti explores how this extended visit prompted a concern for and commitment to democracy that shaped the rest of his work.
Mariotti analyzes the extensive and undervalued works Adorno composed in English for an American audience and traces the development of his political theory during the World War II era. Her unique study examines how Adorno changed his writing style while in the United States in order to directly address the public, which lay at the heart of his theoretical concerns. Despite his apparent contempt for popular culture, his work during this period clearly engages with a broader public in ways that reflect a deep desire to understand the problems and possibilities of democracy as enacted through the customs and habits of Americans. Ultimately, Adorno advances a theory of democratic leadership that works through pedagogy to cultivate a more robust and meaningful practice of citizenship.
Mariotti incisively demonstrates how Adorno's unconventional and challenging interpretations of US culture can add conceptual rigor to political theory and remind Americans of the normative promise of democracy.Adorno and Democracyis an innovative contribution to critical debates about contemporary US politics.
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