Utilization of VAS satellite data in the initialization of an oceanic-cyclogenesis simulation

A series of experiments was performed to test various method of incorporating Visible Infrared Spin Scan Radiometer Atmospheric Sounder (VAS)-sounding data into the initial conditions of the Penn State University/National Center for Atmospheric mesoscale model. The VAS data for this ocean-cyclogenesis case consist of 110 irregularly distributed temperature and humidity soundings located over the North Pacific Ocean and apply at approximately 1200 GMT 10 November 1981. Various methods of utilizing VAS data in the initial condition of a mesoscale model were evaluated

Lower Levels of Glutathione (GSH) in the Brains of Secondary Progressive Multiple Sclerosis Patients Measured by 1H Magnetic Resonance Chemical Shift Imaging at 3 T

BACKGROUND: Disability levels for patients with secondary progressive multiple sclerosis (SPMS) often worsen despite a stable MRI T2 lesion burden. The presence of oxidative stress in the absence of measurable inflammation could help explain this phenomenon. In this study, the assessment of an in vivo marker of oxidative stress, cerebral glutathione (GSH), using magnetic resonance chemical shift imaging (CSI) is described, and GSH levels were compared in patients with SPMS and healthy controls. OBJECTIVE: To assess whether GSH, a key antioxidant in the brain, is lower in the SPMS patients compared to matched controls. METHODS: Seventeen patients with SPMS (Expanded Disability Status Scale = 4.0–7.0; length of MS diagnosis = 19.4±7 years) and 17 age- and gender-matched healthy controls were studied. GSH levels were measured in the fronto-parietal regions of the brain using a specially designed magnetic resonance spectroscopy technique, CSI of GSH, at 3T. RESULTS: The levels of GSH were lower for SPMS patients than for controls, the largest reduction (18.5%) being in the frontal region (p=0.001). CONCLUSION: The lower GSH levels in these patients indicate the presence of oxidative stress in SPMS. This process could be at least partially responsible for ongoing functional decline in SPMS

New Synthesis: Animal Communication Mediated by Microbes: Fact or Fantasy?

No abstract available

Seasonal forcing of summer dissolved inorganic carbon and chlorophyll a on the western shelf of the Antarctic Peninsula

Author Posting. © American Geophysical Union, 2010. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 115 (2010): C03024, doi:10.1029/2009JC005267.The Southern Ocean is a climatically sensitive region that plays an important role in the regional and global modulation of atmospheric CO2. Based on satellite-derived sea ice data, wind and cloudiness estimates from numerical models (National Centers for Environmental Prediction-National Center for Atmospheric Research reanalysis), and in situ measurements of surface (0–20 m depth) chlorophyll a (ChlSurf) and dissolved inorganic carbon (DICSurf) concentration, we show sea ice concentration from June to November and spring wind patterns between 1979 and 2006 had a significant influence on midsummer (January) primary productivity and carbonate chemistry for the Western Shelf of the Antarctic Peninsula (WAP, 64°–68°S, 63.4°–73.3°W). In general, strong (>3.5 m s−1) and persistent (>2 months) northerly winds during the previous spring were associated with relatively high (monthly mean > 2 mg m−3) ChlSurf and low (monthly mean 200 m depth) “winter-like” DIC on the WAP.This research was supported by NSF OPP grants 0217282 to HWD at the Virginia Institute of Marine Science and 0823101 to HWD at the MBL

Calibration and Validation of an Innovative Approach for Estimating General Cognitive Performance

Objective: To evaluate a new approach for creating a composite measure of cognitive function, we calibrated a measure of general cognitive performance from existing neuropsychological batteries. Methods: We applied our approach in an epidemiological study and scaled the composite to a nationally representative sample of older adults. Criterion validity was evaluated against standard clinical diagnoses. Convergent validity was evaluated against the Mini-Mental State Examination (MMSE). Results: The general cognitive performance factor was scaled to have a mean of 50 and standard deviation of 10 in a nationally representative sample of older adults. A cutoff point of approximately 45, corresponding to an MMSE of 23/24, optimally discriminated participants with and without dementia (sensitivity = 0.94, specificity = 0.90, area under the curve = 0.97). The general cognitive performance factor was internally consistent (Cronbach's α = 0.91) and provided reliable measures of functional ability across a wide range of cognitive functioning. It demonstrated minimal floor and ceiling effects, which is an improvement over most individual cognitive tests. Conclusions: The cognitive composite is a highly reliable measure, with minimal floor and ceiling effects. We calibrated it using a nationally representative sample of adults over the age of 70 in the USA and established diagnostically relevant cutoff points. Our methods can be used to harmonize neuropsychological test results across diverse settings and studies

Weed Seed Bank Emergence across the Corn Belt

Field experiments, conducted from 1991 to 1994, generated information on weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of weed seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of these species were as follows: giant foxtail, 31.2 (84%); velvetleaf, 28.2 (66); kochia, 25.7 (79); Pennsylvania smartweed, 25.1 (65); common purslane, 15.4 (135); common ragweed, 15.0 (110); green foxtail, 8.5 (72); wild proso millet, 6.6 (104); hairy nightshade, 5.2 (62); common sunflower, 5.0 (26); yellow foxtail, 3.4 (67); pigweed species, 3.3 (103); common lambsquarters, 2.7 (111); wild buckwheat, 2.5 (63), and prostrate knotweed, 0.6 (79). Variation among site-years, for some species, could be attributed to microclimate variables thought to induce secondary dormancy in spring. For example, total seasonal emergence percentage of giant foxtail was related positively to the 1st date at which average daily soil temperature at 5 to 10 cm soil depth reached 16 C. Thus, if soil warmed before mid April, secondary dormancy was induced and few seedlings emerged, whereas many seedlings emerged if soil remained cool until June

Weed Seed Bank Emergence across the Corn Belt

Field experiments, conducted from 1991 to 1994, generated information on weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of weed seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of these species were as follows: giant foxtail, 31.2 (84%); velvetleaf, 28.2 (66); kochia, 25.7 (79); Pennsylvania smartweed, 25.1 (65); common purslane, 15.4 (135); common ragweed, 15.0 (110); green foxtail, 8.5 (72); wild proso millet, 6.6 (104); hairy nightshade, 5.2 (62); common sunflower, 5.0 (26); yellow foxtail, 3.4 (67); pigweed species, 3.3 (103); common lambsquarters, 2.7 (111); wild buckwheat, 2.5 (63), and prostrate knotweed, 0.6 (79). Variation among site-years, for some species, could be attributed to microclimate variables thought to induce secondary dormancy in spring. For example, total seasonal emergence percentage of giant foxtail was related positively to the 1st date at which average daily soil temperature at 5 to 10 cm soil depth reached 16 C. Thus, if soil warmed before mid April, secondary dormancy was induced and few seedlings emerged, whereas many seedlings emerged if soil remained cool until June

Effects of a nanoscopic filler on the structure and dynamics of a simulated polymer melt and the relationship to ultra-thin films

We perform molecular dynamics simulations of an idealized polymer melt surrounding a nanoscopic filler particle to probe the effects of a filler on the local melt structure and dynamics. We show that the glass transition temperature $T_g$ of the melt can be shifted to either higher or lower temperatures by appropriately tuning the interactions between polymer and filler. A gradual change of the polymer dynamics approaching the filler surface causes the change in the glass transition. We also find that while the bulk structure of the polymers changes little, the polymers close to the surface tend to be elongated and flattened, independent of the type of interaction we study. Consequently, the dynamics appear strongly influenced by the interactions, while the melt structure is only altered by the geometric constraints imposed by the presence of the filler. Our findings show a strong similarity to those obtained for ultra-thin polymer films (thickness $\lesssim 100$ nm) suggesting that both ultra-thin films and filled-polymer systems might be understood in the same context

FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY

The Pennsylvania State University, under contract to the U.S. Department of Energy, National Energy Technology Laboratory is performing a feasibility analysis on installing a state-of-the-art circulating fluidized bed boiler and ceramic filter emission control device at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal, and developing a test program to evaluate cofiring multiple biofuels and coal-based feedstocks. The objective of the project is being accomplished using a team that includes personnel from Penn State's Energy Institute, Office of Physical Plant, and College of Agricultural Sciences; Foster Wheeler Energy Services, Inc.; Parsons Energy and Chemicals Group, Inc.; and Cofiring Alternatives. During this reporting period, work focused on performing the design of the conceptual fluidized bed system and determining the system economics