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The Regional Arctic System Model (RASM) is a fully coupled limited-domain climate system model that has been used for modeling and prediction of Arctic climate change at time scales from weeks to decades. Its pan-Arctic domain extends south to ~30oN in the North Pacific and to ~40oN in the North Atlantic oceans. The RASM ocean and sea ice model components are configured on rotated sphere meshes with the default configuration of 1/12o(~9.3km), while the atmosphere and land components are configured on a 50-km grid. Its boundary conditions along the lateral boundaries and in the upper atmosphere are derived either from global atmospheric reanalyses or from Earth System Model (ESM) simulations. RASM hindcasts allow comparisons of results with observations in place and time, which is a unique capability not available in ESMs. Within this framework, RASM has been used to downscale output from three global models: the National Center for Environmental Predictions Coupled Forecast System version 2 (CFSv2), the National Center for Atmospheric Research Community Earth System Model initialized Decadal Predictability Large Ensemble (CESM-DPLE), and the Department of Energy Energy Exascale Earth System Model (E3SM). Forced with CFSv2, RASM has produced probabilistic intra-annual forecasts each month for the past 4+ years. The CESM-DPLE and E3SM output was used for downscaling multi decadal simulations. Here, we present a review of some of these results, including evaluation of RASM sea ice predictive skill in comparison with observations and relative to the original global output using the common metrics to quantify model skill., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Objective Apolipoprotein (ApoE)-e4 is well established as a genetic risk factor for Alzheimer’s disease (AD) as well as a predictor for the rate of cognitive decline in AD. Among older adults without dementia, some research has found that e4 carriers have worse episodic memory compared to e4 non-carriers, whereas others have not found this association. The present study examined differences in cognitive performance between ApoE-e4 carriers and non-carriers. Method 91 non-demented individuals (age range: 55–87) were genotyped for ApoE (41 e4 carriers, 49 e4 non-carriers) and completed neuropsychological testing as a part of a longitudinal study at the Center for Neurodegeneration and Translational Neuroscience. Cognitively normal (CN) and mild cognitive impairment (MCI) participants were included (41 CN, 49 MCI). Group differences between e4 carriers and non-carriers were compared across cognitive measures after controlling for age, gender, and education. Results In the total sample, e4 carriers performed significantly worse across measures of verbal and nonverbal memory, as well as on the Boston Naming Test and Symbol Digit Modalities Test (all p’s Conclusion(s) These findings support that ApoE-e4 positivity is associated with worse cognitive performance, especially on tasks related to medial temporal lobe function, among non-demented older adults. In MCI, worse verbal memory in e4 carriers likely reflects increased progression of underlying AD pathology.

Genomic analyses often involve scanning for potential transcription factor (TF) binding sites using models of the sequence specificity of DNA binding proteins. Many approaches have been developed to model and learn a protein's DNA-binding specificity, but these methods have not been systematically compared. Here we applied 26 such approaches to in vitro protein binding microarray data for 66 mouse TFs belonging to various families. For nine TFs, we also scored the resulting motif models on in vivo data, and found that the best in vitro-derived motifs performed similarly to motifs derived from the in vivo data. Our results indicate that simple models based on mononucleotide position weight matrices trained by the best methods perform similarly to more complex models for most TFs examined, but fall short in specific cases (

The article of record as published may be found at http://dx.doi.org/10.1016/j.dsr.2012.04.001 Sparse information is available on the communication between the northern North Pacific and the southern Bering Sea. We present results from a multi-decadal simulation of a high-resolution, pan-Arctic ice-ocean model to address the long-term mean and variability and synthesize limited observations in the Alaskan Stream, Western Subarctic Gyre, and southern Bering Sea. While the mean circulation in the Bering Sea basin is cyclonic, during the 26-year simulation meanders and eddies are continuously present throughout the region, which is consistent with observations from Cokelet and Stabeno (1997). Prediction (instead of prescription) of the Alaskan Stream and Aleutian throughflow allows reproduction of meanders and eddies in the Alaskan Stream and Kamchatka Current similar to those that have been observed previously (e.g. Crawford et al., 2000; Rogachev and Carmack, 2002; Rogachev and Gorin, 2004). Interannual variability in mass transport and property fluxes is particularly strong across the western Aleutian Island Passes, including Buldir Pass, Near Strait, and Kamchatka Strait. Much of this variability can be attributed to the presence of meanders and eddies found both north and south of the passes, which are found to directly cause periodic flow reversals and maxima in the western passes. Given that modeled flow reversals and maxima last for time periods ranging between three months and two years, short-term observations (months to few years) may not be representative of the actual mean flow. These extremes in the communication across the Aleutian Island Passes have a large impact on the oceanic environmental conditions in the southern Bering Sea and could directly impact biological species there and further downstream. Therefore, we identify a need for continuous monitoring of the flow through Buldir Pass, Near, and Kamchatka straits. Energy Climate and Environmental Sciences Division of the Biological and Environmental Research program National Science Foundation Office of Polar Programs Office of Naval Research US Department of Defense High Performance Computer Modernization Program (HPCMP), for computer resources

X-ray tomographic microscopy (XTM), a three-dimensional X-ray imaging technique, has been used to quantitatively map mineral concentrations in carious dentin. Data analysis from the XTM study indicates that variations in the mineral concentration surrounding the caries can be imaged in three dimensions with a spatial resolution that is sufficient to detect calcified and enlarged tubule spaces in the lesion. A three-dimensional image of the subsurface lesion indicates that lesion penetration is along the direction of the tubules. The mineral concentration in the uninfected dentin was measured by the XTM to be 1.29 ± 0.14 g/cm3 based upon the tabulated X-ray attenuation coefficients for apatite. This value is in excellent agreement with averaged estimates for the mineral concentration in dentin (1.4 g/cm3). Furthermore, the mineral concentration determined using XTM varies from 2.25 g/cm3 in the remineralized dentin to as low as 0.55 ± 0.17 g/cm3 in the demineralized tissue. The high concentration of mineral in the remineralized region suggests that organic matter is lost and mineral is deposited at some time during the caries process.