383 research outputs found
Book Review: \u3ci\u3eThe Flat World and Education\u3c/i\u3e The Importance of Linda Darling-Hammondâs Latest Book to Reading Recovery Professionals
Toward an Ontology of Collaborative Learning Healthcaresystems
Objective:To establish a basis for a domain ontology - a formal, explicit specificationof a shared conceptualization - of collaborative learning healthcare systems (CLHSs)in order to facilitate measurement, explanation, and improvement.Methods:We adapted theâMethontologyâapproach to begin building an ontologyof CLHSs. We specified the purpose of an ontology, acquired domain knowledge vialiterature review, conceptualized a common framework of CLHSs using a groundedapproach, refined these concepts based on expert panel input, and illustrated con-cept application via four cases.Results:The set of concepts identified as important to include in an ontologyincludes goals, values, structure, actors, environment, and products. To establish thisset of concepts, we gathered input from content experts in two ways. First, expertpanel methods were used to elicit feedback on these concepts and to test the elicita-tion of terms for the vocabulary of the Values concept. Second, from these discus-sions we developed a mapping exercise to test the intuitiveness of the concepts,requesting that network leaders from four CLHSs complete a mapping exercise toassociate characteristics of their networks with the high-level concepts, building thevocabulary for each concept in a grounded fashion. We also solicited feedback fromthese participants on the experience of completing the mapping exercise, finding thatthe exercise is acceptable and could aid in CLHS development and collaboration.Respondents identified opportunities to improve the operational definitions of eachconcept to ensure that corresponding vocabularies are distinct and non-overlapping.Discussion:Our results provide a foundation for developing a formal, explicit sharedconceptualization of CLHSs. Once developed, such a tool can be useful for measure-ment, explanation, and improvement. Further work, including alignment to a top-levelontology, expanding the vocabulary, and defining relations between vocabulary isrequired to formally build out an ontology for these uses
The CCSM4 ocean component
Author Posting. © American Meteorological Society, 2012. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 25 (2012): 1361â1389, doi:10.1175/JCLI-D-11-00091.1.The ocean component of the Community Climate System Model version 4 (CCSM4) is described, and its solutions from the twentieth-century (20C) simulations are documented in comparison with observations and those of CCSM3. The improvements to the ocean model physical processes include new parameterizations to represent previously missing physics and modifications of existing parameterizations to incorporate recent new developments. In comparison with CCSM3, the new solutions show some significant improvements that can be attributed to these model changes. These include a better equatorial current structure, a sharper thermocline, and elimination of the cold bias of the equatorial cold tongue all in the Pacific Ocean; reduced sea surface temperature (SST) and salinity biases along the North Atlantic Current path; and much smaller potential temperature and salinity biases in the near-surface Pacific Ocean. Other improvements include a global-mean SST that is more consistent with the present-day observations due to a different spinup procedure from that used in CCSM3. Despite these improvements, many of the biases present in CCSM3 still exist in CCSM4. A major concern continues to be the substantial heat content loss in the ocean during the preindustrial control simulation from which the 20C cases start. This heat loss largely reflects the top of the atmospheric model heat loss rate in the coupled system, and it essentially determines the abyssal ocean potential temperature biases in the 20C simulations. There is also a deep salty bias in all basins. As a result of this latter bias in the deep North Atlantic, the parameterized overflow waters cannot penetrate much deeper than in CCSM3.NCAR is sponsored by the National
Science Foundation. The CCSM is also sponsored by
the Department of Energy. SGY was supported by the
NOAA Climate Program Office under Climate Variability
and Predictability Program Grant NA09OAR4310163.2012-09-0
Human feeder cell line for derivation and culture of hESc/hiPSc
AbstractWe have generated a human feeder cell line from early second trimester Placental Stromal Fibroblasts (ihPSF) stably over-expressing the polycomb protein BMI-1. These feeder cells retain the ability to maintain human Embryonic Stem cells (hESc) over long-term culture whereas hTERT or BMI-1/hTERT immortalised feeder cell lines do not. ihPSFs were able to support the derivation of a new hESc line in near xenofree (free of non-human animal components) conditions and support continued culture of newly derived hESc and human induced Pluripotent Stem (hiPS) cell lines in complete xenofree conditions necessary for clinical use
Patient-specific iPSC model of a genetic vascular dementia syndrome reveals failure of mural cells to stabilize capillary structures
CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is the most common form of genetic stroke and vascular dementia syndrome resulting from mutations in NOTCH3. To elucidate molecular mechanisms of the condition and identify drug targets, we established a patient-specific induced pluripotent stem cell (iPSC) model and demonstrated for the first time a failure of the patient iPSC-derived vascular mural cells (iPSC-MCs) in engaging and stabilizing endothelial capillary structures. The patient iPSC-MCs had reduced platelet-derived growth factor receptor ÎČ, decreased secretion of the angiogenic factor vascular endothelial growth factor (VEGF), were highly susceptible to apoptotic insults, and could induce apoptosis of adjacent endothelial cells. Supplementation of VEGF significantly rescued the capillary destabilization. Small interfering RNA knockdown of NOTCH3 in iPSC-MCs revealed a gain-of-function mechanism for the mutant NOTCH3. These disease mechanisms likely delay brain repair after stroke in CADASIL, contributing to the brain hypoperfusion and dementia in this condition, and will help to identify potential drug targets
Mean biases, variability, and trends in airâsea fluxes and sea surface temperature in the CCSM4
Author Posting. © American Meteorological Society, 2012. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 25 (2012): 7781â7801, doi:10.1175/JCLI-D-11-00442.1.Airâsea fluxes from the Community Climate System Model version 4 (CCSM4) are compared with the Coordinated Ocean-Ice Reference Experiment (CORE) dataset to assess present-day mean biases, variability errors, and late twentieth-century trend differences. CCSM4 is improved over the previous version, CCSM3, in both airâsea heat and freshwater fluxes in some regions; however, a large increase in net shortwave radiation into the ocean may contribute to an enhanced hydrological cycle. The authors provide a new baseline for assessment of flux variance at annual and interannual frequency bands in future model versions and contribute a new metric for assessing the coupling between the atmospheric and oceanic planetary boundary layer (PBL) schemes of any climate model. Maps of the ratio of CCSM4 variance to CORE reveal that variance on annual time scales has larger error than on interannual time scales and that different processes cause errors in mean, annual, and interannual frequency bands. Air temperature and specific humidity in the CCSM4 atmospheric boundary layer (ABL) follow the sea surface conditions much more closely than is found in CORE. Sensible and latent heat fluxes are less of a negative feedback to sea surface temperature warming in the CCSM4 than in the CORE data with the modelâs PBL allowing for more heating of the oceanâs surface.The CESM project is supported
by the National Science Foundation and the Office
of Science (BER) of the U.S. Department of Energy.
S. Stevensonwas supported byNASAGrantNNX09A020H
and B. Fox-Kemper by Grants NSF 0934737 and NASA
NNX09AF38G.2013-05-1
Polymer Supported Directed Differentiation Reveals a Unique Gene Signature Which Predicts Stable Hepatocyte Performance
- âŠ