Uniform boundedness of oscillatory singular integrals on Hardy spaces

We prove the uniform H1 boundedness of oscillatory singular integrals with degenerate phase functions

More than a Number: Unexpected Benefits of Return on Investment Analysis

In 2010–2011, University of Colorado (CU) librarians implemented a multi-campus pilot study to measure the institutional value of library resources used by faculty in their research. The study incorporated quantitative methods including return on investment (ROI), cost benefit analysis (CBA), and citation analysis of journal articles published by faculty; and qualitative methodologies such as in-person interviews with faculty. The study resulted in a CU ROI model that can be used to measure faculty perceptions of value and the economic benefits of electronic journal collections for faculty research in terms of ROI. The CU ROI methodology provides outcomes beyond a single ROI number and led to unexpected benefits for informing collection development decisions and strategies

A comparative study of discriminating human heart failure etiology using gene expression profiles

BACKGROUND: Human heart failure is a complex disease that manifests from multiple genetic and environmental factors. Although ischemic and non-ischemic heart disease present clinically with many similar decreases in ventricular function, emerging work suggests that they are distinct diseases with different responses to therapy. The ability to distinguish between ischemic and non-ischemic heart failure may be essential to guide appropriate therapy and determine prognosis for successful treatment. In this paper we consider discriminating the etiologies of heart failure using gene expression libraries from two separate institutions. RESULTS: We apply five new statistical methods, including partial least squares, penalized partial least squares, LASSO, nearest shrunken centroids and random forest, to two real datasets and compare their performance for multiclass classification. It is found that the five statistical methods perform similarly on each of the two datasets: it is difficult to correctly distinguish the etiologies of heart failure in one dataset whereas it is easy for the other one. In a simulation study, it is confirmed that the five methods tend to have close performance, though the random forest seems to have a slight edge. CONCLUSIONS: For some gene expression data, several recently developed discriminant methods may perform similarly. More importantly, one must remain cautious when assessing the discriminating performance using gene expression profiles based on a small dataset; our analysis suggests the importance of utilizing multiple or larger datasets

Detecting Compaction Disequilibrium with Anisotropy of Magnetic Susceptibility

In clay-rich sediment, microstructures and macrostructures influence how sediments deform when under stress. When lithology is fairly constant, anisotropy of magnetic susceptibility (AMS) can be a simple technique for measuring the relative consolidation state of sediment, which reflects the sediment burial history. AMS can reveal areas of high water content and apparent overconsolidation associated with unconformities where sediment overburden has been removed. Many other methods for testing consolidation and water content are destructive and invasive, whereas AMS provides a nondestructive means to focus on areas for additional geotechnical study. In zones where the magnetic minerals are undergoing diagenesis, AMS should not be used for detecting compaction state. By utilizing AMS in the Santa Barbara Basin, we were able to identify one clear unconformity and eight zones of high water content in three cores. With the addition of susceptibility, anhysteretic remanent magnetization, and isothermal remanent magnetization rock magnetic techniques, we excluded 3 out of 11 zones from being compaction disequilibria. The AMS signals for these three zones are the result of diagenesis, coring deformation, and burrows. In addition, using AMS eigenvectors, we are able to accurately show the direction of maximum compression for the accumulation zone of the Gaviota Slide

The Adsorption of H2O on TiO2 and SnO2(110) Studied by First-Principles Calculations

First-principles calculations based on density functional theory and the pseudopotential method have been used to investigate the energetics of H$_2$O adsorption on the (110) surface of TiO$_2$ and SnO$_2$. Full relaxation of all atomic positions is performed on slab systems with periodic boundary conditions, and the cases of full and half coverage are studied. Both molecular and dissociative (H$_2$O $\rightarrow$ OH$^-$ + H$^+$) adsorption are treated, and allowance is made for relaxation of the adsorbed species to unsymmetrical configurations. It is found that for both TiO$_2$ and SnO$_2$ an unsymmetrical dissociated configuration is the most stable. The symmetrical molecularly adsorbed configuration is unstable with respect to lowering of symmetry, and is separated from the fully dissociated configuration by at most a very small energy barrier. The calculated dissociative adsorption energies for TiO$_2$ and SnO$_2$ are in reasonable agreement with the results of thermal desorption experiments. Calculated total and local electronic densities of states for dissociatively and molecularly adsorbed configurations are presented and their relation with experimental UPS spectra is discussed

Waldo Lake Research in 2004

The Willamette National Forest has worked with Portland State University, Center for Lakes and Reservoirs (PSU) and the University of Oregon (UO) to investigate ecosystem changes, provide guidance on long-term monitoring methods, assess monitoring data, develop predictive water quality models, and conduct research that will lead to better protection and understanding of the Waldo Lake ecosystem. This report summarizes the second year of collaborative PSU-UO research at Waldo Lake. Research has focused on understanding physical, chemical and biological characteristics of Waldo Lake across a range of spatial and temporal scales. Research tasks that continued from 2003 into 2004 included temperature monitoring, hydrodynamic and water quality model development, climate and hydrological forcing scenario investigation, bathymetric map refinement, and analysis of phytoplankton and zooplankton community changes. Research tasks initiated in 2004 included evaluation of wavelength-specific light attenuation, diel phytoplankton and zooplankton vertical distribution patterns, phytoplankton photoinhibition and photoprotection, and the role of mixotrophy in the pelagic microbial food web. Preliminary efforts were made to characterize Waldo Lake benthos through assessment of algal species diversity and chemical composition of the benthic community, as very little is currently known about the Waldo Lake benthic ecosystem. In addition, an attempt was made to map benthic substrate types through reinterpretation of data collected during the 2003 bathymetric survey

Anthracene Diphosphate Ligands for CdSe Quantum Dots; Molecular Design for Efficient Upconversion

Quantum dot (QD)-sensitized photon upconversion follows a multi-step energy transfer process from the QD to transmitter ligand to a soluble annihilator. Using a novel 10-R-anthracene-1,8-diphosphoric acid (R = octyl, 2-hexyldecyl, phenyl) ligand with high binding affinity for CdSe QD surfaces, we demonstrate a photon upconversion process that is limited by the transmitter to annihilator transfer efficiency. Using 1H NMR spectroscopy, we demonstrate that these bidentate diphosphate ligands rapidly and irreversibly displace two carboxylate ligands. These ligands mediate energy transfer from the photoexcited QDs to a triplet annihilator (1,10-diphenylanthracene), producing overall photon upconversion quantum efficiencies as high as 17%, the highest for QDs with no shells. Transient absorption spectroscopy shows that the anthracene dihydrogen phosphate (ADP) ligand supports a 3.4 fold longer triplet state lifetime compared to 9-anthracene carboxylic acid (299.9 ± 9.5 vs 88.2 ± 2.1 μs), increasing the probability of energy transfer

Dietary and Pharmacologic Manipulations of Host Lipids and Their Interaction with the Gut Microbiome in Non-Human Primates

The gut microbiome influences nutrient processing as well as host physiology. Plasma lipid levels have been associated with the microbiome, although the underlying mechanisms are largely unknown, and the effects of dietary lipids on the gut microbiome in humans are not well-studied. We used a compilation of four studies utilizing non-human primates (Chlorocebus aethiops and Macaca fascicularis) with treatments that manipulated plasma lipid levels using dietary and pharmacological techniques, and characterized the microbiome using 16S rDNA. High-fat diets significantly reduced alpha diversity (Shannon) and the Firmicutes/Bacteroidetes ratio compared to chow diets, even when the diets had different compositions and were applied in different orders. When analyzed for differential abundance using DESeq2, Bulleidia, Clostridium, Ruminococcus, Eubacterium, Coprocacillus, Lachnospira, Blautia, Coprococcus, and Oscillospira were greater in both chow diets while Succinivibrio, Collinsella, Streptococcus, and Lactococcus were greater in both high-fat diets (oleic blend or lard fat source). Dietary cholesterol levels did not affect the microbiome and neither did alterations of plasma lipid levels through treatments of miR-33 antisense oligonucleotide (anti-miR-33), Niemann–Pick C1-Like 1 (NPC1L1) antisense oligonucleotide (ASO), and inducible degrader of LDLR (IDOL) ASO. However, a liver X receptor (LXR) agonist shifted the microbiome and decreased bile acid levels. Fifteen genera increased with the LXR agonist, while seven genera decreased. Pseudomonas increased on the LXR agonist and was negatively correlated to deoxycholic acid, cholic acid, and total bile acids while Ruminococcus was positively correlated with taurolithocholic acid and taurodeoxycholic acid. Seven of the nine bile acids identified in the feces significantly decreased due to the LXR agonist, and total bile acids (nmol/g) was reduced by 62%. These results indicate that plasma lipid levels have, at most, a modest effect on the microbiome, whereas bile acids, derived in part from plasma lipids, are likely responsible for the indirect relationship between lipid levels and the microbiome

A Cautionary Tale: MARVELS Brown Dwarf Candidate Reveals Itself To Be A Very Long Period, Highly Eccentric Spectroscopic Stellar Binary

We report the discovery of a highly eccentric, double-lined spectroscopic binary star system (TYC 3010-1494-1), comprising two solar-type stars that we had initially identified as a single star with a brown dwarf companion. At the moderate resolving power of the MARVELS spectrograph and the spectrographs used for subsequent radial-velocity (RV) measurements (R ~ <30,000), this particular stellar binary mimics a single-lined binary with an RV signal that would be induced by a brown dwarf companion (Msin(i)~50 M_Jup) to a solar-type primary. At least three properties of this system allow it to masquerade as a single star with a very low-mass companion: its large eccentricity (e~0.8), its relatively long period (P~238 days), and the approximately perpendicular orientation of the semi-major axis with respect to the line of sight (omega~189 degrees). As a result of these properties, for ~95% of the orbit the two sets of stellar spectral lines are completely blended, and the RV measurements based on centroiding on the apparently single-lined spectrum is very well fit by an orbit solution indicative of a brown dwarf companion on a more circular orbit (e~0.3). Only during the ~5% of the orbit near periastron passage does the true, double-lined nature and large RV amplitude of ~15 km/s reveal itself. The discovery of this binary system is an important lesson for RV surveys searching for substellar companions; at a given resolution and observing cadence, a survey will be susceptible to these kinds of astrophysical false positives for a range of orbital parameters. Finally, for surveys like MARVELS that lack the resolution for a useful line bisector analysis, it is imperative to monitor the peak of the cross-correlation function for suspicious changes in width or shape, so that such false positives can be flagged during the candidate vetting process.Comment: 16 pages, 11 figures, 6 table