Modeling lake conductivity in the contiguous United States using spatial indexing for big spatial data.

Conductivity is an important indicator of the health of aquatic ecosystems. We model large amounts of lake conductivity data collected as part of the United States Environmental Protection Agency's National Lakes Assessment using spatial indexing, a flexible and efficient approach to fitting spatial statistical models to big data sets. Spatial indexing is capable of accommodating various spatial covariance structures as well as features like random effects, geometric anisotropy, partition factors, and non-Euclidean topologies.

Structures and ammonia synthesis activity of hexagonal ruthenium iron nitride phases.

A series of ruthenium iron nitride phases with Ru:Fe ratios of ca. 1:3 were synthesized by ammonolysis. When the ammonolysis temperature was above 500°C, the obtained RuFeN materials had a ε-FeN (622) structure, while two similar phases were present when the ammonolysis was lower than 500°C.

Multiscale Investigation of the Mechanism and Selectivity of CO Hydrogenation over Rh(111).

CO hydrogenation over Rh catalysts comprises multiple reaction pathways, presenting a wide range of possible intermediates and end products, with selectivity toward either CO or methane being of particular interest. We investigate in detail the reaction mechanism of CO hydrogenation to the single-carbon (C1) products on the Rh(111) facet by performing periodic density functional theory (DFT) calculations and kinetic Monte Carlo (kMC) simulations, which account for the adsorbate interactions through a cluster expansion approach. We observe that Rh readily facilitates the dissociation of hydrogen, thus contributing to the subsequent hydrogenation processes.

Exploring the relationship of supernumerary recurrent renal calculi formation and tick-borne infections: a case report.

A 51-year-old male with a history of Cacchi-Ricci disease and long-standing infection with various species of presented with recurrent symptoms of right-sided flank pain. Numerous renal calculi were identified on imaging. The etiology of the calculi had not been previously elucidated.

Defining Research Funding Priorities: Emergency Nurses Association Foundation.

Introduction: Establishing research priorities provides focus and direction for limited resources among organizations and increasing impact in a focused area. The Emergency Nurses Association (ENA) Foundation sought to identify research priorities to guide funding decisions in its extramural grants program.

Methods: A modified Delphi research strategy was used to build consensus among ENA members and key leaders to determine research focus areas.

Indexing and partitioning the spatial linear model for large data sets.

We consider four main goals when fitting spatial linear models: 1) estimating covariance parameters, 2) estimating fixed effects, 3) kriging (making point predictions), and 4) block-kriging (predicting the average value over a region). Each of these goals can present different challenges when analyzing large spatial data sets. Current research uses a variety of methods, including spatial basis functions (reduced rank), covariance tapering, etc, to achieve these goals.

An Application of Spatio-temporal Modeling to Finite Population Abundance Prediction.

Spatio-temporal models can be used to analyze data collected at various spatial locations throughout multiple time points. However, even with a finite number of spatial locations, there may be a lack of resources to collect data from every spatial location at every time point. We develop a spatio-temporal finite-population block kriging (ST-FPBK) method to predict a quantity of interest, such as a mean or total, across a finite number of spatial locations.

A Comparison of the Reactivity of the Lattice Nitrogen in Tungsten Substituted Co Mo N and Ni Mo N.

The effect of the partial substitution of Mo with W in Co Mo N and Ni Mo N on ammonia synthesis activity and lattice nitrogen reactivity has been investigated. This is of interest as the coordination environment of lattice N is changed by this process. When tungsten was introduced into the metal nitrides by substitution of Mo atoms, the catalytic performance was observed to have decreased.

sptotal: an R package for predicting totals and weighted sums from spatial data.

In ecological or environmental surveys, it is often desired to predict the mean or total of a variable in some finite region. However, because of time and money constraints, sampling the entire region is often unfeasible. The purpose of the sptotal R package is to provide software that gives a prediction for a quantity of interest, such as a total, and an associated standard error for the prediction.

Survey assessment of HIV pre-exposure prophylaxis availability in student health services in New England colleges and universities.

To determine HIV pre-exposure prophylaxis (PrEP) availability at student health services (SHS) in New England. We conducted an electronic survey of medical directors of SHS at New England colleges and universities. We measured the availability and volume of PrEP prescribing, barriers and facilitators to prescribing and provider knowledge.

Case report: Co-occurring autism spectrum disorder (Level One) and obsessive-compulsive disorder in a gender-diverse adolescent.

This fictionalized case report captures the common themes and considerations during the diagnostic assessment and behavioral treatment of adolescents demonstrating symptoms of autism spectrum disorder (ASD), obsessive-compulsive disorder (OCD), and attention-deficit/hyperactivity disorder (ADHD), as well as gender-diversity concerns. Our patient was a white, non-Hispanic 17-year-old individual who identified as gender-neutral but had been assigned female at birth. Symptoms presented were social withdrawal, rigid rule-following behavior, unusual repetitive behavior, impairments in social communication skills, sensory sensitivity, body dissatisfaction, self-injury, and anxiety related to contamination, perfectionism, and social interactions.

Interfacial Chemistry in the Electrocatalytic Hydrogenation of CO over C-Supported Cu-Based Systems.

Operando soft and hard X-ray spectroscopic techniques were used in combination with plane-wave density functional theory (DFT) simulations to rationalize the enhanced activities of Zn-containing Cu nanostructured electrocatalysts in the electrocatalytic CO hydrogenation reaction. We show that at a potential for CO hydrogenation, Zn is alloyed with Cu in the bulk of the nanoparticles with no metallic Zn segregated; at the interface, low reducible Cu(I)-O species are consumed. Additional spectroscopic features are observed, which are identified as various surface Cu(I) ligated species; these respond to the potential, revealing characteristic interfacial dynamics.

Experimental and theoretical investigations on the anti-perovskite nitrides CoCuN, NiCuN and CoMoN for ammonia synthesis.

The ammonia synthesis activities of the anti-perovskite nitrides CoCuN and NiCuN have been compared to investigate the possible metal composition-activity relationship. Post-reaction elemental analysis showed that the activity for both nitrides was due to loss of lattice nitrogen rather than a catalytic process. CoCuN was observed to convert a higher percentage of lattice nitrogen to ammonia than NiCuN and was active at a lower temperature.

Mechanism of ammonia synthesis on FeMoN.

Ammonia (NH) synthesis is an essential yet energy-demanding industrial process. Hence, there is a need to develop NH synthesis catalysts that are highly active under milder conditions. Metal nitrides are promising candidates, with the η-carbide CoMoN having been found to be more active than the industrial Fe-based catalyst.

spmodel: Spatial statistical modeling and prediction in [Formula: see text].

spmodel is an [Formula: see text] package used to fit, summarize, and predict for a variety spatial statistical models applied to point-referenced or areal (lattice) data. Parameters are estimated using various methods, including likelihood-based optimization and weighted least squares based on variograms. Additional modeling features include anisotropy, non-spatial random effects, partition factors, big data approaches, and more.

A comparison of design-based and model-based approaches for finite population spatial sampling and inference.

The design-based and model-based approaches to frequentist statistical inference rest on fundamentally different foundations. In the design-based approach, inference relies on random sampling. In the model-based approach, inference relies on distributional assumptions.

Discovery of an Antarctic Ascidian-Associated Uncultivated with Antimelanoma Palmerolide Biosynthetic Potential.

The Antarctic marine ecosystem harbors a wealth of biological and chemical innovation that has risen in concert over millennia since the isolation of the continent and formation of the Antarctic circumpolar current. Scientific inquiry into the novelty of marine natural products produced by Antarctic benthic invertebrates led to the discovery of a bioactive macrolide, palmerolide A, that has specific activity against melanoma and holds considerable promise as an anticancer therapeutic. While this compound was isolated from the Antarctic ascidian Synoicum adareanum, its biosynthesis has since been hypothesized to be microbially mediated, given structural similarities to microbially produced hybrid nonribosomal peptide-polyketide macrolides.

Uncovering the Core Microbiome and Distribution of Palmerolide in Across the Anvers Island Archipelago Antarctica.

Polar marine ecosystems hold the potential for bioactive compound biodiscovery, based on their untapped macro- and microorganism diversity. Characterization of polar benthic marine invertebrate-associated microbiomes is limited to few studies. This study was motivated by our interest in better understanding the microbiome structure and composition of the ascidian, , in which palmerolide A (PalA), a bioactive macrolide with specificity against melanoma, was isolated.

Mechanism of CO conversion to methanol over Cu(110) and Cu(100) surfaces.

Density functional methods are applied to explore the reaction mechanism for CO hydrogenation to methanol over low-index Cu surfaces, namely Cu(110) and Cu(100). A detailed reaction network is obtained, examining several different possible mechanistic routes, including methanol formation via formate and hydrocarboxyl bound intermediates, the role of formaldehyde and formic acid as stable intermediary reaction products, as well as exploring the possibility of CO dissociation and subsequent hydrogenation of the resultant CO. We find that, in contrast to the dominant Cu(111) facet, the Cu(110) and Cu(100) surfaces facilitate a moderate extent of CO activation, which results in lower activation barriers for initial elementary processes involving CO hydrogenation and dissociation, opening up reaction pathways considered unfeasible for Cu(111).

Synergistic ultraviolet and visible light photo-activation enables intensified low-temperature methanol synthesis over copper/zinc oxide/alumina.

Although photoexcitation has been employed to unlock the low-temperature equilibrium regimes of thermal catalysis, mechanism underlining potential interplay between electron excitations and surface chemical processes remains elusive. Here, we report an associative zinc oxide band-gap excitation and copper plasmonic excitation that can cooperatively promote methanol-production at the copper-zinc oxide interfacial perimeter of copper/zinc oxide/alumina (CZA) catalyst. Conversely, selective excitation of individual components only leads to the promotion of carbon monoxide production.

Viewpoint: Why you should provide HIV pre-exposure prophylaxis (PrEP) at your college health center.

By providing HIV pre-exposure prophylaxis, or PrEP (a single daily oral pill), in a primary care college health setting, clinical providers can make a dramatic contribution to the current and long-term health and well-being of the students they see. This viewpoint article describes the approach taken to instituting primary care PrEP services at two college health programs. It delineates which students might benefit from PrEP and how to prescribe/monitor PrEP over time.

Interplay between surface chemistry and performance of rutile-type catalysts for halogen production.

Catalytic HBr oxidation is an integral step in the bromine-mediated functionalisation of alkanes to valuable chemicals. This study establishes the relationships between the mechanism of HBr oxidation over rutile-type oxides (RuO, IrO, TiO) and their apparent catalytic performance. Comparison with the well-studied HCl oxidation revealed distinct differences in surface chemistry between HBr and HCl oxidation that impact the stability and activity of the catalysts.