Temporal variability and predictability predict alpine plant community composition and distribution patterns.

One of the most reliable features of natural systems is that they change through time. Theory predicts that temporally fluctuating conditions shape community composition, species distribution patterns, and life history variation, yet features of temporal variability are rarely incorporated into studies of species-environment associations. In this study, we evaluated how two components of temporal environmental variation-variability and predictability-impact plant community composition and species distribution patterns in the alpine tundra of the Southern Rocky Mountains in Colorado (USA).

Nanoscale Iron Redistribution during Thermochemical Decomposition of CaTi Fe O Alters the Electrical Transport Pathway: Implications for Oxygen-Transport Membranes, Electrocatalysis, and Photocatalysis.

Potential applications of the earth-abundant, low-cost, and non-critical perovskite CaTi Fe O in electrocatalysis, photocatalysis, and oxygen-transport membranes have motivated research to tune its chemical composition and morphology. However, investigations on the decomposition mechanism(s) of CaTi Fe O under thermochemically reducing conditions are limited, and direct evidence of the nano- and atomic-level decomposition process is not available in the literature. In this work, the phase evolution of CaTi Fe O ( = 0-0.

Exsolution-Driven Surface Transformation in the Host Oxide.

Exsolution synthesizes self-assembled metal nanoparticle catalysts via phase precipitation. An overlooked aspect in this method thus far is how exsolution affects the host oxide surface chemistry and structure. Such information is critical as the oxide itself can also contribute to the overall catalytic activity.

Do trade-offs govern plant species' responses to different global change treatments?

Plants are subject to trade-offs among growth strategies such that adaptations for optimal growth in one condition can preclude optimal growth in another. Thus, we predicted that a plant species that responds positively to one global change treatment would be less likely than average to respond positively to another treatment, particularly for pairs of treatments that favor distinct traits. We examined plant species' abundances in 39 global change experiments manipulating two or more of the following: CO , nitrogen, phosphorus, water, temperature, or disturbance.

Probing Multiscale Disorder in Pyrochlore and Related Complex Oxides in the Transmission Electron Microscope: A Review.

Transmission electron microscopy (TEM), and its counterpart, scanning TEM (STEM), are powerful materials characterization tools capable of probing crystal structure, composition, charge distribution, electronic structure, and bonding down to the atomic scale. Recent (S)TEM instrumentation developments such as electron beam aberration-correction as well as faster and more efficient signal detection systems have given rise to new and more powerful experimental methods, some of which (e.g.

Bulk and surface exsolution produces a variety of Fe-rich and Fe-depleted ellipsoidal nanostructures in LaSrFeO thin films.

The past several years have seen a resurgence in the popularity of metal exsolution as an approach to synthesize advanced materials proposed for novel catalytic, magnetic, optical, and electrochemical properties. Whereas most studies to-date have focused on surface exsolution (motivated by catalysis), we instead report on the diversity of nanostructures formed in LaSrFeO thin films during sub-surface or so-called 'bulk' exsolution, in addition to surface exsolution. Bulk exsolution is a promising approach to tuning the functionality of materials, yet there is little understanding of the nanostructures exsolved within the bulk and how they compare to those exsolved at gas-solid interfaces.

Temporal variability in production is not consistently affected by global change drivers across herbaceous-dominated ecosystems.

Understanding how global change drivers (GCDs) affect aboveground net primary production (ANPP) through time is essential to predicting the reliability and maintenance of ecosystem function and services in the future. While GCDs, such as drought, warming and elevated nutrients, are known to affect mean ANPP, less is known about how they affect inter-annual variability in ANPP. We examined 27 global change experiments located in 11 different herbaceous ecosystems that varied in both abiotic and biotic conditions, to investigate changes in the mean and temporal variability of ANPP (measured as the coefficient of variation) in response to different GCD manipulations, including resource additions, warming, and irrigation.

Linking Macroscopic and Nanoscopic Ionic Conductivity: A Semiempirical Framework for Characterizing Grain Boundary Conductivity in Polycrystalline Ceramics.

Understanding the chemical and charge transport properties of grain boundaries (GBs) with high point defect concentrations (beyond the dilute solution limit) in polycrystalline materials is critical for developing ion-conducting solids for electrochemical energy conversion and storage. Elucidation and optimization of GBs are hindered by large variations in atomic structure, composition, and chemistry within nanometers or Ångstroms of the GB interface, which limits a fundamental understanding of electrical transport across and along GBs. Here we employ a novel correlated approach that is generally applicable to polycrystalline materials whose properties are affected by GB composition or chemistry.

Global change effects on plant communities are magnified by time and the number of global change factors imposed.

Global change drivers (GCDs) are expected to alter community structure and consequently, the services that ecosystems provide. Yet, few experimental investigations have examined effects of GCDs on plant community structure across multiple ecosystem types, and those that do exist present conflicting patterns. In an unprecedented global synthesis of over 100 experiments that manipulated factors linked to GCDs, we show that herbaceous plant community responses depend on experimental manipulation length and number of factors manipulated.

Microwave-assisted synthesis and in vitro stability of N-benzylamide non-steroidal anti-inflammatory drug conjugates for CNS delivery.

More effective delivery of non-steroidal anti-inflammatory drugs (NSAIDs) to the brain could treat the underlying inflammatory pathology of a range of CNS diseases and conditions. Use of a blood-brain barrier shuttle such as the N-benzylamide moiety, which has been largely unexplored for this purpose, could improve the brain bioavailabilities of NSAIDs. A series of novel N-benzylamide NSAID conjugates was synthesized via a three-step process with a microwave-assisted bimolecular nucleophilic substitution as the final step.

Ambient changes exceed treatment effects on plant species abundance in global change experiments.

The responses of species to environmental changes will determine future community composition and ecosystem function. Many syntheses of global change experiments examine the magnitude of treatment effect sizes, but we lack an understanding of how plant responses to treatments compare to ongoing changes in the unmanipulated (ambient or background) system. We used a database of long-term global change studies manipulating CO , nutrients, water, and temperature to answer three questions: (a) How do changes in plant species abundance in ambient plots relate to those in treated plots? (b) How does the magnitude of ambient change in species-level abundance over time relate to responsiveness to global change treatments? (c) Does the direction of species-level responses to global change treatments differ from the direction of ambient change? We estimated temporal trends in plant abundance for 791 plant species in ambient and treated plots across 16 long-term global change experiments yielding 2,116 experiment-species-treatment combinations.

Limited ecosystem recovery from simulated chronic nitrogen deposition.

The realization that anthropogenic nitrogen (N) deposition is causing significant environmental change in many ecosystems has led to lower emissions of reactive N and deposition rates in many regions. However, the impacts of N deposition on terrestrial ecosystems can be long lasting, with significant inertia in the return of the biota and biogeochemical processes to baseline levels. To better understand patterns of recovery and the factors that may contribute to slow or no responses following declines in N deposition, we followed plant species composition, microbial abundance, N cycling rates, soil pH, and pools of NO and extractable cations in an impacted alpine ecosystem following cessation of 12-yr experiment increasing N deposition rates by 0, 20, 40, and 60 kg N·ha ·yr .

Enhanced ionic conductivity in electroceramics by nanoscale enrichment of grain boundaries with high solute concentration.

The enhancement of oxygen ionic conductivity by over two orders of magnitude in an electroceramic oxide is explicitly shown to result from nanoscale enrichment of a grain boundary layer or complexion with high solute concentration. A series of CaCeO polycrystalline oxides with fluorite structure and varying nominal Ca solute concentration elucidates how local grain boundary composition, rather than structural grain boundary character, primarily regulates ionic conductivity. A correlation between high grain boundary solute concentration above ∼40 mol%, and four orders of magnitude increase in grain boundary conductivity is explicitly shown.

Asynchrony among local communities stabilises ecosystem function of metacommunities.

Temporal stability of ecosystem functioning increases the predictability and reliability of ecosystem services, and understanding the drivers of stability across spatial scales is important for land management and policy decisions. We used species-level abundance data from 62 plant communities across five continents to assess mechanisms of temporal stability across spatial scales. We assessed how asynchrony (i.

Pleuropulmonary Blastoma: A Single-center Case Series of 6 Patients.

Pleuropulmonary blastoma (PPB) is a rare malignancy of childhood which when left untreated often shows pathologic progression resulting in a more aggressive neoplasm with an increasingly poor prognosis. Because of this it is important to diagnose and initiate treatment early. However, early stage PPB can appear as a cystic lung lesion on imaging and can be easily misdiagnosed given the rarity of the malignancy.

Designing Strained Interface Heterostructures for Memristive Devices.

Ionic heterostructures are used as a strain-modulated memristive device based on the model system Gd Ce O /Er O to set and tune the property of "memristance." The modulation of interfacial strain and the interface count is used to engineer the R /R ratio and the persistence of the system. A model describing the variation of mixed ionic-electronic mobilities and defect concentrations is presented.

Conditional vulnerability of plant diversity to atmospheric nitrogen deposition across the United States.

Atmospheric nitrogen (N) deposition has been shown to decrease plant species richness along regional deposition gradients in Europe and in experimental manipulations. However, the general response of species richness to N deposition across different vegetation types, soil conditions, and climates remains largely unknown even though responses may be contingent on these environmental factors. We assessed the effect of N deposition on herbaceous richness for 15,136 forest, woodland, shrubland, and grassland sites across the continental United States, to address how edaphic and climatic conditions altered vulnerability to this stressor.

Soil bacterial community structure remains stable over a 5-year chronosequence of insect-induced tree mortality.

Extensive tree mortality from insect epidemics has raised concern over possible effects on soil biogeochemical processes. Yet despite the importance of microbes in nutrient cycling, how soil bacterial communities respond to insect-induced tree mortality is largely unknown. We examined soil bacterial community structure (via 16S rRNA gene pyrosequencing) and community assembly processes (via null deviation analysis) along a 5-year chronosequence (substituting space for time) of bark beetle-induced tree mortality in the southern Rocky Mountains, USA.

Prognostic factors in children with acute myeloid leukaemia and excellent response to remission induction therapy.

Minimal residual disease (MRD) is a strong prognostic factor in children and adolescents with acute myeloid leukaemia (AML) but nearly one-quarter of patients who achieve MRD-negative status still relapse. The adverse prognostic factors among MRD-negative patients remain unknown. We analysed the AML02 study cohort to identify demographic and genetic prognostic factors.

Nitrogen critical loads for alpine vegetation and soils in Rocky Mountain National Park.

We evaluated the ecological thresholds associated with vegetation and soil responses to nitrogen (N) deposition, by adding NH(4)NO(3) in solution at rates of 5, 10 and 30 kg N ha(-1) yr(-1) to plots in a species rich dry meadow alpine community in Rocky Mountain National Park receiving ambient N deposition of 4 kg N ha(-1) yr(-1). To determine the levels of N input that elicited changes, we measured plant species composition annually, and performed one-time measurements of aboveground biomass and N concentrations, soil solution and resin bag inorganic N, soil pH, and soil extractable cations after 3 years of N additions. Our goal was to use these dose-response relationships to provide N critical loads for vegetation and soils for the alpine in Rocky Mountain National Park.

A high C/O ratio and weak thermal inversion in the atmosphere of exoplanet WASP-12b.

The carbon-to-oxygen ratio (C/O) in a planet provides critical information about its primordial origins and subsequent evolution. A primordial C/O greater than 0.8 causes a carbide-dominated interior, as opposed to the silicate-dominated composition found on Earth; the atmosphere can also differ from those in the Solar System.

Niche complementarity due to plasticity in resource use: plant partitioning of chemical N forms.

Niche complementarity, in which coexisting species use different forms of a resource, has been widely invoked to explain some of the most debated patterns in ecology, including maintenance of diversity and relationships between diversity and ecosystem function. However, classical models assume resource specialization in the form of distinct niches, which does not obviously apply to the broadly overlapping resource use in plant communities. Here we utilize an experimental framework based on competition theory to test whether plants partition resources via classical niche differentiation or via plasticity in resource use.

Possible thermochemical disequilibrium in the atmosphere of the exoplanet GJ 436b.

The nearby extrasolar planet GJ 436b-which has been labelled as a 'hot Neptune'-reveals itself by the dimming of light as it crosses in front of and behind its parent star as seen from Earth. Respectively known as the primary transit and secondary eclipse, the former constrains the planet's radius and mass, and the latter constrains the planet's temperature and, with measurements at multiple wavelengths, its atmospheric composition. Previous work using transmission spectroscopy failed to detect the 1.

Links between plant litter chemistry, species diversity, and below-ground ecosystem function.

Decomposition is a critical source of plant nutrients, and drives the largest flux of terrestrial C to the atmosphere. Decomposing soil organic matter typically contains litter from multiple plant species, yet we lack a mechanistic understanding of how species diversity influences decomposition processes. Here, we show that soil C and N cycling during decomposition are controlled by the composition and diversity of chemical compounds within plant litter mixtures, rather than by simple metrics of plant species diversity.