Shifting Data Collection from a Fixed to an Adaptive Sampling Paradigm

For domains where data are difficult to obtain due to human or resource limitations, an emphasis is needed to efficiently explore the dimensions of information spaces to acquire any given response of interest. Many disciplines are still making the transition from brute force, dense, full factorial exploration of their information spaces to a more efficient design of experiments approach; the latter being in use successfully for many decades in agricultural and automotive applications. Although this transition is still incomplete, groundwork must be laid for incorporating the next generation of algorithms to adaptively explore the information space in response to data collected, as well as any resulting empirical models (i.e., metamodels). The methodology in the present work was to compare metamodel quality using a fixed sampling technique compared to an adaptive sampling technique based on metamodel variance. In order to quantify metamodeling errors, a delta method was used to provide quantitative model variance estimates. The present methodology was applied to a design space with an air-breathing engine performance response. It was shown that competitive metamodel quality with lower associated error could be achieved for an adaptive sampling technique for the same level of effort as a fixed, a priori sampling technique

Newspaper Theft, Self-Preservation and the Dimensions of Censorship

One of the most common yet understudied means of suppressing free expression on college and university campuses is the theft of freely-distributed student publications, particularly newspapers. This study examines news accounts of nearly 300 newspaper theft incidents at colleges and universities between 1995 and 2008 in order to identify the manifestations and consequences of this peculiar form of censorship, and to augment existing research on censorship and tolerance by looking, not at what people say about free expression, but at what they do when they have the power of censorship in their own hands. Among the key findings is that men commit nearly 70% of newspaper thefts, which is inconsistent with much of the existing research on censorship and gender, and that those who censor college newspapers are far more concerned with their own self-preservation than with shaping public dialog on controversial social or political issues

Comment on "Geometric phases for mixed states during cyclic evolutions"

It is shown that a recently suggested concept of mixed state geometric phase in cyclic evolutions [2004 {\it J. Phys. A} {\bf 37} 3699] is gauge dependent.Comment: Comment to the paper L.-B. Fu and J.-L. Chen, J. Phys. A 37, 3699 (2004); small changes; journal reference adde

Viability of subitaneous eggs of the copepod, Acartia tonsa (Dana), following exposure to various cryoprotectants and hypersaline water

Subitaneous eggs were obtained from monocultures of the calanoid copepod Acartia tonsa (Dana), Gulf of Mexico strain. Eggs were exposed to methanol, ethylene glycol, propylene glycol, glycerine, and DMSO at 0.0, 0.1, 0.5, 1.0, 2.0, and 5.0 M and hypersaline water at 50, 75, 100, 150, and 200 g/L. Treatments were evaluated after 10 and 20 min of exposure and at 4 and 26 °C. Viability (percent hatched) was determined after 24 h of incubation in 35 g/L saltwater at 26 °C. Methanol, ethylene glycol, and glycerine had high viability up to 2M, and all experienced large decreases at 5M when the exposure temperature was 26 °C compared to 4 °C. Eggs exposed to propylene glycol had lower mean viability with greater variability at the lower concentrations although viability was greater than 81.4% at 2 M. Significant decreases in viability were observed at 5 M, and the decreases were much greater at an exposure temperature of 26 °C versus 4 °C. DMSO exposed at 26 °C produced high viability up to 1 M before significant decreases occurred, while an exposure temperature of 4 °C produced high viability up to 2 M. Viability of eggs exposed to hypersaline water of 50, 75, and 100 g/L were not significantly different from controls for all treatment combinations except the 26 °C temperature exposed for 20 min, which was significantly lower at 100 g/L. Concentrations of 150 and 200 g/L produced very few to no viable eggs. These results indicate further research is justified to investigate if viability of A. tonsa eggs can be protected by these cryoprotectants and hypersaline water after exposure to cryopreservation conditions

Dirac operators and spectral triples for some fractal sets built on curves

We construct spectral triples and, in particular, Dirac operators, for the algebra of continuous functions on certain compact metric spaces. The triples are countable sums of triples where each summand is based on a curve in the space. Several fractals, like a finitely summable infinite tree and the Sierpinski gasket, fit naturally within our framework. In these cases, we show that our spectral triples do describe the geodesic distance and the Minkowski dimension as well as, more generally, the complex fractal dimensions of the space. Furthermore, in the case of the Sierpinski gasket, the associated Dixmier-type trace coincides with the normalized Hausdorff measure of dimension $\log 3/ \log 2$.Comment: 48 pages, 4 figures. Elementary proofs omitted. To appear in Adv. Mat

Suboptimal \u3cem\u3eTrichomonas vaginalis\u3c/em\u3e Antigen Test Performance in a Low-Prevalence Sexually Transmitted Infection Community

Trichomonas vaginalis is the most common nonviral etiology of sexually transmitted infection (STI) worldwide. The OSOM Trichomonas rapid test (OSOM; Sekisui Diagnostics, San Diego, CA) is a rapid surrogate to microscopic analysis in symptomatic patients, but its performance in low-prevalence STI populations has been assessed on a limited basis in the literature. OSOM has widespread usage, as accreditation data from the College of American Pathologists report that over 300 participant laboratories utilize this assay on an annual basis. We sought to characterize the analytical and clinical performance of OSOM in a low-prevalence STI population on the basis of a commercial transcription-mediated amplification (TMA) reference

Update on Laboratory Diagnosis and Epidemiology of \u3cem\u3eTrichomonas vaginalis\u3c/em\u3e: You Can Teach an “Old” Dog “New” Trichs

Past viewpoints on Trichomonas vaginalis infection have characterized the associated clinical disease as a “nuisance” condition, with affected demographics largely being older African American females residing in urban centers. The advent of commercial molecular assays specific for T. vaginalis has offered a new outlook on trichomoniasis. Within high-prevalence sexually transmitted infection populations, parasite distribution is not localized to specific population centers, and T. vaginalis prevalence is elevated among both younger and older age groups. Adaptation of these molecular assays can additionally facilitate male screening and subsequent epidemiologic characterization. These findings, combined with associations between T. vaginalis infection and human immunodeficiency virus (HIV) acquisition/transmission and persistent human papillomavirus infection, support consideration of the expansion of T. vaginalis screening efforts in the realms of clinical practice and public health

Exploratory Mediation Analysis with Many Potential Mediators

Social and behavioral scientists are increasingly employing technologies such as fMRI, smartphones, and gene sequencing, which yield 'high-dimensional' datasets with more columns than rows. There is increasing interest, but little substantive theory, in the role the variables in these data play in known processes. This necessitates exploratory mediation analysis, for which structural equation modeling is the benchmark method. However, this method cannot perform mediation analysis with more variables than observations. One option is to run a series of univariate mediation models, which incorrectly assumes independence of the mediators. Another option is regularization, but the available implementations may lead to high false positive rates. In this paper, we develop a hybrid approach which uses components of both filter and regularization: the 'Coordinate-wise Mediation Filter'. It performs filtering conditional on the other selected mediators. We show through simulation that it improves performance over existing methods. Finally, we provide an empirical example, showing how our method may be used for epigenetic research.Comment: R code and package are available online as supplementary material at https://github.com/vankesteren/cmfilter and https://github.com/vankesteren/ema_simulation

An Economic Evaluation of Incineration as a Residual Municipal Solid Waste Management Option in Ireland

The Environmental Protection Agency (EPA) and National Competitiveness Council (NCC) report that despite pressing EU policy requirements, Ireland remains heavily dependent on indigenous landfill capacity and overseas markets for its Residual Solid Waste (RMSW) reprocessing and waste to energy capacities. This deficit threatens Ireland’s competitiveness and its environmental policy objectives. In the context of government revisions to national waste policy, economic analysis should underpin the policy choices used to identify indigenous RMSW management alternatives to landfill. This paper seeks to make a contribution to the debate by evaluating the RMSW treatment option of incineration by performing a cost-benefit analysis (CBA). The research demonstrates that certain configurations of RMSW incineration can provide a net benefit, relative to the status quo of landfilling RMSW in Ireland. In doing so, the study illustrates the sensitivity of an incineration project’s benefits to its scale, operational costs and its capacity to recover energy. It finds that incineration does not provide a net benefit relative to landfill, if its scale and energy recovery capacity are insufficient. The methodology may be adapted to evaluate other RMSW infrastructure options e.g. mechanical, biological treatment (MBT).Cost-benefit analysis, Residual municipal solid waste, Incineration, Ireland