Risk And Protective Factors Related to Female/Male Use Of Alcohol In Grades 7-12

The purpose of this study was to investigate risk and protective factors related to the use of alcohol during a 30-day time frame for 7th-12 th grade females/males. The comparisons were male non-users to male users, female non-users to female users, and male users to female users. Data were collected from the spring 2003 Grand Forks (North Dakota) Public Schools Youth Risk and Protective Factor Survey (YRPFS). The study was conducted with 666 students: 375 were in grades 7-9 and 291 were in grades 10-12. There were 340 females and 326 males. MANOVA was used to investigate the differences between the comparison groups. The level of significance was set at .01. There were significant differences found at all grade levels for male and female non-users and users of alcohol. Non-users were more likely to have protective factor influences (e.g., personal perception, parent perception, and positive beliefs). Users were more likely to have risk factor influences (e.g., other drug use; friend\u27s influence; school drug use; alcohol, tobacco, and other drug (ATOD) school availability; and ATOD community availability). There were slight variations between male and female users; males were higher on risk factors, other drug use, and ATOD community availability. There were no significant differences found within any of the comparison groups on 5 of the 14 factors. These were personal support, parent/school involvement, parental relationships, home violence, and school safety. In conclusion, this study found there were specific risk and protective factors that influenced the non-use and use of alcohol by males and females at all grade levels. There were very few differences for male and female users: males were higher on only two of the factors. This study provided significant findings that can be used to develop strategies to promote protective factors and reduce risk factors. Some of the specific recommendations included the need to use these findings and further research on risk/protective factors as a guide to reduce/eliminate the use of alcohol by adolescents. These results must be shared with youth, parents, schools, and communities to develop a collaborative action plan that will promote healthy youth development

Response of a marine-terminating Greenland outlet glacier to abrupt cooling 8200 and 9300 years ago

Long-term records of Greenland outlet-glacier change extending beyond the satellite era can inform future predictions of Greenland Ice Sheet behavior. Of particular relevance is elucidating the Greenland Ice Sheet's response to decadal- and centennial-scale climate change. Here, we reconstruct the early Holocene history of Jakobshavn Isbræ, Greenland's largest outlet glacier, using 10Be surface exposure ages and 14C-dated lake sediments. Our chronology of ice-margin change demonstrates that Jakobshavn Isbræ advanced to deposit moraines in response to abrupt cooling recorded in central Greenland ice cores ca. 8,200 and 9,300 years ago. While the rapid, dynamically aided retreat of many Greenland outlet glaciers in response to warming is well documented, these results indicate that marine-terminating outlet glaciers are also able to respond quickly to cooling. We suggest that short lag times of high ice flux margins enable a greater magnitude response of marine-terminating outlets to abrupt climate change compared to their land-terminating counterparts

Ultraviolet Radiation from Evolved Stellar Populations -- I. Models

This series of papers comprises a systematic exploration of the hypothesis that the far ultraviolet radiation from star clusters and elliptical galaxies originates from extremely hot horizontal-branch (HB) stars and their post-HB progeny. This first paper presents an extensive grid of calculations of stellar models from the Zero Age Horizontal Branch through to a point late in post-HB evolution or a point on the white dwarf cooling track. We use the term `Extreme Horizontal Branch' (EHB) to refer to HB sequences of constant mass that do not reach the thermally-pulsing stage on the AGB. These models evolve after core helium exhaustionComment: Paper is uuencoded compressed PostScript file. Figures for this paper are available from through anonymous ftp://ftp.virginia.edu/public_access/bd4r/uv1fig.u

A decision tree algorithm for investigation of model biases related to dynamical cores and physical parameterizations

An object‐based evaluation method using a pattern recognition algorithm (i.e., classification trees) is applied to the simulated orographic precipitation for idealized experimental setups using the National Center of Atmospheric Research (NCAR) Community Atmosphere Model (CAM) with the finite volume (FV) and the Eulerian spectral transform dynamical cores with varying resolutions. Daily simulations were analyzed and three different types of precipitation features were identified by the classification tree algorithm. The statistical characteristics of these features (i.e., maximum value, mean value, and variance) were calculated to quantify the difference between the dynamical cores and changing resolutions. Even with the simple and smooth topography in the idealized setups, complexity in the precipitation fields simulated by the models develops quickly. The classification tree algorithm using objective thresholding successfully detected different types of precipitation features even as the complexity of the precipitation field increased. The results show that the complexity and the bias introduced in small‐scale phenomena due to the spectral transform method of CAM Eulerian spectral dynamical core is prominent, and is an important reason for its dissimilarity from the FV dynamical core. The resolvable scales, both in horizontal and vertical dimensions, have significant effect on the simulation of precipitation. The results of this study also suggest that an efficient and informative study about the biases produced by GCMs should involve daily (or even hourly) output (rather than monthly mean) analysis over local scales.Key PointsThe complexity and the bias introduced in small‐scale phenomena due to the spectral transform method of CAM Eulerian spectral dynamical core are prominentThe classification tree algorithm with objective thresholding is successful in detecting different types of precipitation features with high spatial complexityAn efficient and informative study about the biases produced by GCMs should involve daily (or hourly) output (rather than monthly mean) analysis over local scalesPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/136040/1/jame20331.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/136040/2/jame20331_am.pd

A persistent and dynamic East Greenland Ice Sheet over the past 7.5 million years

Climate models show that ice-sheet melt will dominate sea-level rise over the coming centuries, but our understanding of ice-sheet variations before the last interglacial 125,000 years ago remains fragmentary. This is because terrestrial deposits of ancient glacial and interglacial periods1,2,3 are overrun and eroded by more recent glacial advances, and are therefore usually rare, isolated and poorly dated4. In contrast, material shed almost continuously from continents is preserved as marine sediment that can be analysed to infer the time-varying state of major ice sheets. Here we show that the East Greenland Ice Sheet existed over the past 7.5 million years, as indicated by beryllium and aluminium isotopes (10Be and 26Al) in quartz sand removed by deep, ongoing glacial erosion on land and deposited offshore in the marine sedimentary record5,6. During the early Pleistocene epoch, ice cover in East Greenland was dynamic; in contrast, East Greenland was mostly ice-covered during the mid-to-late Pleistocene. The isotope record we present is consistent with distinct signatures of changes in ice sheet behaviour coincident with major climate transitions. Although our data are continuous, they are from low-deposition-rate sites and sourced only from East Greenland. Consequently, the signal of extensive deglaciation during short, intense interglacials could be missed or blurred, and we cannot distinguish between a remnant ice sheet in the East Greenland highlands and a diminished continent-wide ice sheet. A clearer constraint on the behaviour of the ice sheet during past and, ultimately, future interglacial warmth could be produced by 10Be and 26Al records from a coring site with a higher deposition rate. Nonetheless, our analysis challenges the possibility of complete and extended deglaciation over the past several million years

Note and Comment

The Law School; Unauthorized Operation by Physician; The Kansas Oil Refinery Bill; Garnishment of Public Corporations; The rule in Wild\u27s Case Today; Effect of a complicated Form of Ballot on the Elector\u27s Freedom of Choice; Situs of Debts for Garnishment; Malicious Interference With the Contract of Employmen

Software Testing and Verification in Climate Model Development

Over the past 30 years most climate models have grown from relatively simple representations of a few atmospheric processes to a complex multi-disciplinary system. Computer infrastructure over that period has gone from punch card mainframes to modem parallel clusters. Model implementations have become complex, brittle, and increasingly difficult to extend and maintain. Existing verification processes for model implementations rely almost exclusively upon some combination of detailed analysis of output from full climate simulations and system-level regression tests. In additional to being quite costly in terms of developer time and computing resources, these testing methodologies are limited in terms of the types of defects that can be detected, isolated and diagnosed. Mitigating these weaknesses of coarse-grained testing with finer-grained "unit" tests has been perceived as cumbersome and counter-productive. In the commercial software sector, recent advances in tools and methodology have led to a renaissance for systematic fine-grained testing. We discuss the availability of analogous tools for scientific software and examine benefits that similar testing methodologies could bring to climate modeling software. We describe the unique challenges faced when testing complex numerical algorithms and suggest techniques to minimize and/or eliminate the difficulties