Observations of Unsteady Airfoil Flows

http://deepblue.lib.umich.edu/bitstream/2027.42/96610/1/39015087358597.pd

Development of a web-enabled learning platform for geospatial laboratories: improving the undergraduate learning experience

This paper describes a web-enabled learning platform providing remote access to geospatial software that extends the learning experience outside of the laboratory setting. The platform was piloted in two undergraduate courses, and includes a software server, a data server, and remote student users. The platform was designed to improve the quality of the learning experience and to increase student confidence and proficiency with software-based geospatial skills. Laboratory grades of students using the platform were significantly higher than those of students who did not use the platform, and survey responses reported that students overwhelmingly liked the convenience of the platform, which allowed them to work from any location

Direct Improvement of Hamiltonian Lattice Gauge Theory

We demonstrate that a direct approach to improving Hamiltonian lattice gauge theory is possible. Our approach is to correct errors in the Kogut-Susskind Hamiltonian by incorporating additional gauge invariant terms. The coefficients of these terms are chosen so that the order $a^2$ classical errors vanish. We conclude with a brief discussion of tadpole improvement in Hamiltonian lattice gauge theory.Comment: 9 page

Mercury Toolset for Spatiotemporal Metadata

Mercury (http://mercury.ornl.gov) is a set of tools for federated harvesting, searching, and retrieving metadata, particularly spatiotemporal metadata. Version 3.0 of the Mercury toolset provides orders of magnitude improvements in search speed, support for additional metadata formats, integration with Google Maps for spatial queries, facetted type search, support for RSS (Really Simple Syndication) delivery of search results, and enhanced customization to meet the needs of the multiple projects that use Mercury. It provides a single portal to very quickly search for data and information contained in disparate data management systems, each of which may use different metadata formats. Mercury harvests metadata and key data from contributing project servers distributed around the world and builds a centralized index. The search interfaces then allow the users to perform a variety of fielded, spatial, and temporal searches across these metadata sources. This centralized repository of metadata with distributed data sources provides extremely fast search results to the user, while allowing data providers to advertise the availability of their data and maintain complete control and ownership of that data. Mercury periodically (typically daily) harvests metadata sources through a collection of interfaces and re-indexes these metadata to provide extremely rapid search capabilities, even over collections with tens of millions of metadata records. A number of both graphical and application interfaces have been constructed within Mercury, to enable both human users and other computer programs to perform queries. Mercury was also designed to support multiple different projects, so that the particular fields that can be queried and used with search filters are easy to configure for each different project

Metal-directed columnar phase formation in tetrahedral zinc(II) and manganese(II) metallomesogens

New, non-discoid M(II) complexes [MCl2(L)] {M = Mn, Zn; L = 2,6-diformyl-4- methylphenolbis[3’,4’,5’-tris(hexadecyloxy)phenylimine]} have been prepared and shown to exhibit columnar mesophases, the nature of which was found to be metal-dependent. As analysed by DSC and small-angle X-ray diffraction experiments, the complex [ZnCl2(L)] exhibits a single mesophase with rectangular symmetry (Colr) between 46 and 145 °C, whereas the Mn(II) analogue [MnCl2(L)] displays a purely hexagonal mesophase (Colh) phase between 55 and 285 °C. By combining these results with those obtained from dilatometry, a model for the molecular organisation within the columnar mesophases is proposed. The single-crystal X-ray structure of the related complex [Zn(NO3)(L’)2]NO3.3MeOH {L’ = 2,6-diformyl-4-methylphenolbis[3’,4’,5’-tris(methoxy)phenylimine]} has been determined and supports the proposed mode of binding of the ligand to the metal via only one imine and a phenol

Data citation in the wild

Consistent attribution of research data upon reuse is necessary to reward the original data-producing investigators, reconstruct provenance, and inform data sharing policies, tool requirements, and funding decisions. Unfortunately, norms for data attribution are varied and often weak. As part of the DataONE 2010 summer internship program, three interns studied the policies, practice, and implications of current data attribution behavior in the environmental sciences. We found that few policies recommend robust data citation practices: in our preliminary evaluation, only one-third of repositories (n=26), 6% of journals (n=307), and 1 of 53 funders suggested a best practice for data citation. We manually reviewed 500 papers published between 2000 and 2010 across six journals; of the 198 papers that reused datasets, only 14% reported a unique dataset identifier in their dataset attribution, and a partially-overlapping 12% mentioned the author name and repository name. Few citations to datasets themselves were made in the article references section. In multivariate analysis, citation patterns were more correlated with repository (with citations to Genbank being most complete) than journal or datatype. Attribution patterns were found to be steady over time. Consistent with these findings, dataset reuse was difficult to track through standard retrieval resources. Searching by repository name retrieved many instances of data submission rather than data reuse, combing the citation history of data creation articles was time consuming, and searching citation databases for the few early-adopter dataset DOIs and HDLs in reference lists failed due to apparent limitations in database query capabilities and structured extraction of DOIs. We hope these descriptions of the current data attribution environment will highlight outstanding issues and motivate change in policy, tools, and practice. This research was done as open science (http://openwetware.org/wiki/DataONE:Notebook/Summer_2010): ask us about it

Modeling the mental health service utilization decisions of university undergraduates: A discrete choice conjoint experiment

Objective: We modeled design factors influencing the intent to use a university mental health service. Participants: Between November 2012 and October 2014, 909 undergraduates participated. Method: Using a discrete choice experiment, participants chose between hypothetical campus mental health services. Results: Latent class analysis identified three segments. A Psychological/Psychiatric Service segment (45.5%) was most likely to contact campus health services delivered by psychologists or psychiatrists. An Alternative Service segment (39.3%) preferred to talk to peer-counselors who had experienced mental health problems. A Hesitant segment (15.2%) reported greater distress but seemed less intent on seeking help. They preferred services delivered by psychologists or psychiatrists. Simulations predicted that, rather than waiting for standard counseling, the Alternative Service segment would prefer immediate access to E-Mental health. The Usual Care and Hesitant segments would wait 6 months for standard counseling. Conclusions: E-Mental Health options could engage students who may not wait for standard services.This project was supported by the Jack Laidlaw Chair in Patient-Centered Health Care and a grant from the Canadian Health Services Research Foundation

Prognostic Value of Choline and Betaine Depends on Intestinal Microbiota-Generated Metabolite Trimethylamine-N-Oxide

Aims: Recent metabolomics and animal model studies show trimethylamine-N-oxide (TMAO), an intestinal microbiota-dependent metabolite formed from dietary trimethylamine-containing nutrients such as phosphatidylcholine (PC), choline, and carnitine, is linked to coronary artery disease pathogenesis. Our aim was to examine the prognostic value of systemic choline and betaine levels in stable cardiac patients. Methods and Results: We examined the relationship between fasting plasma choline and betaine levels and risk of major adverse cardiac events (MACE = death, myocardial infraction, stroke) in relation to TMAO over 3 years of follow-up in 3903 sequential stable subjects undergoing elective diagnostic coronary angiography. In our study cohort, median (IQR) TMAO, choline, and betaine levels were 3.7 (2.4–6.2)μM, 9.8 (7.9–12.2)μM, and 41.1 (32.5–52.1)μM, respectively. Modest but statistically significant correlations were noted between TMAO and choline (r = 0.33, P \u3c 0.001) and less between TMAO and betaine (r = 0.09, P \u3c 0.001). Higher plasma choline and betaine levels were associated with a 1.9-fold and 1.4-fold increased risk of MACE, respectively (Quartiles 4 vs. 1; P \u3c 0.01, each). Following adjustments for traditional cardiovascular risk factors and high-sensitivity C-reactive protein, elevated choline [1.34 (1.03–1.74), P \u3c 0.05], and betaine levels [1.33 (1.03–1.73), P \u3c 0.05] each predicted increased MACE risk. Neither choline nor betaine predicted MACE risk when TMAO was added to the adjustment model, and choline and betaine predicted future risk for MACE only when TMAO was elevated. Conclusion: Elevated plasma levels of choline and betaine are each associated with incident MACE risk independent of traditional risk factors. However, high choline and betaine levels are only associated with higher risk of future MACE with concomitant increase in TMAO

XO-2b: Transiting Hot Jupiter in a Metal-rich Common Proper Motion Binary

We report on a V=11.2 early K dwarf, XO-2 (GSC 03413-00005), that hosts a Rp=0.98+0.03/-0.01 Rjup, Mp=0.57+/-0.06 Mjup transiting extrasolar planet, XO-2b, with an orbital period of 2.615857+/-0.000005 days. XO-2 has high metallicity, [Fe/H]=0.45+/-0.02, high proper motion, mu_tot=157 mas/yr, and has a common proper motion stellar companion with 31" separation. The two stars are nearly identical twins, with very similar spectra and apparent magnitudes. Due to the high metallicity, these early K dwarf stars have a mass and radius close to solar, Ms=0.98+/-0.02 Msolar and Rs=0.97+0.02/-0.01 Rsolar. The high proper motion of XO-2 results from an eccentric orbit (Galactic pericenter, Rper<4 kpc) well confined to the Galactic disk (Zmax~100 pc). In addition, the phase space position of XO-2 is near the Hercules dynamical stream, which points to an origin of XO-2 in the metal-rich, inner Thin Disk and subsequent dynamical scattering into the solar neighborhood. We describe an efficient Markov Chain Monte Carlo algorithm for calculating the Bayesian posterior probability of the system parameters from a transit light curve.Comment: 14 pages, 10 Figures, Accepted in ApJ. Negligible changes to XO-2 system properties. Removed Chi^2 light curve analysis section, and simplified MCMC light curve analysis discussio