GABB : A global dataset of alpine breeding birds and their ecological traits

Alpine ecosystems represent varied climates and vegetation structures globally, with the potential to support rich and functionally diverse avian communities. High mountain habitats and species are under significant threat from climate change and other anthropogenic factors. Yet, no global database of alpine birds exists, with most mountain systems lacking basic information on species breeding in alpine habitats, their status and trends, or potential cryptic diversity (i.e., sub-species distributions). To address these critical knowledge gaps, we combined published literature, regional monitoring schemes, and expert knowledge from often inaccessible, data-deficient mountain ranges to develop a global list of alpine breeding bird species with their associated distributions and select ecological traits. This dataset compiles alpine breeding records for 1,310 birds, representing 12.0% of extant species and covering all major mountain regions across each continent, excluding Antarctica. The Global Alpine Breeding Bird dataset (GABB) is an essential resource for research on the ecological and evolutionary factors shaping alpine communities, as well as documenting the value of these high elevation, climate-sensitive habitats for conserving biodiversity.Peer reviewe

Modeling adsorption in metal-organic frameworks with open metal sites : propane/propylene separations

We present a new approach for modeling adsorption in metal-organic frameworks (MOFs) with unsaturated metal centers and apply it to the challenging propane/propylene separation in copper(II) benzene-1,3,5-tricarboxylate (CuBTC). We obtain information about the specific interactions between olefins and the open metal sites of the MOP using quantum mechanical density functional theory. A proper consideration of all the relevant contributions to the adsorption energy enables us to extract the component that is due to specific attractive interactions between the pi-orbitals of the alkene and the coordinatively unsaturated metal. This component is fitted using a combination of a Morse potential and a power law function and is then included into classical grand canonical Monte Carlo simulations of adsorption. Using this modified potential model, together with a standard Lennard-Jones model, we are able to predict the adsorption of not only propane (where no specific interactions are present), but also of propylene (where specific interactions are dominant). Binary adsorption isotherms for this mixture are in reasonable agreement with ideal adsorbed solution theory predictions. We compare our approach with previous attempts to predict adsorption in MOFs with open metal sites and suggest possible future routes for improving our model

Change in albuminuria as a surrogate endpoint for progression of kidney disease: a meta-analysis of treatment effects in randomised clinical trials

Background Change in albuminuria has strong biological plausibility as a surrogate endpoint for progression of chronic kidney disease, but empirical evidence to support its validity is lacking. We aimed to determine the association between treatment effects on early changes in albuminuria and treatment effects on clinical endpoints and surrograte endpoints, to inform the use of albuminuria as a surrogate endpoint in future randomised controlled trials. Methods In this meta-analysis, we searched PubMed for publications in English from Jan 1, 1946, to Dec 15, 2016, using search terms including “chronic kidney disease”, “chronic renal insufficiency”, “albuminuria”, “proteinuria”, and “randomized controlled trial”; key inclusion criteria were quantifiable measurements of albuminuria or proteinuria at baseline and within 12 months of follow-up and information on the incidence of end-stage kidney disease. We requested use of individual patient data from the authors of eligible studies. For all studies that the authors agreed to participate and that had sufficient data, we estimated treatment effects on 6-month change in albuminuria and the composite clinical endpoint of treated end-stage kidney disease, estimated glomerular filtration rate of less than 15 mL/min per 1·73 m2, or doubling of serum creatinine. We used a Bayesian mixed-effects meta-regression analysis to relate the treatment effects on albuminuria to those on the clinical endpoint across studies and developed a prediction model for the treatment effect on the clinical endpoint on the basis of the treatment effect on albuminuria. Findings We identified 41 eligible treatment comparisons from randomised trials (referred to as studies) that provided sufficient patient-level data on 29 979 participants (21 206 [71%] with diabetes). Over a median follow-up of 3·4 years (IQR 2·3–4·2), 3935 (13%) participants reached the composite clinical endpoint. Across all studies, with a meta-regression slope of 0·89 (95% Bayesian credible interval [BCI] 0·13–1·70), each 30% decrease in geometric mean albuminuria by the treatment relative to the control was associated with an average 27% lower hazard for the clinical endpoint (95% BCI 5–45%; median R2 0·47, 95% BCI 0·02–0·96). The association strengthened after restricting analyses to patients with baseline albuminuria of more than 30 mg/g (ie, 3·4 mg/mmol; R2 0·72, 0·05–0·99]). For future trials, the model predicts that treatments that decrease the geometric mean albuminuria to 0·7 (ie, 30% decrease in albuminuria) relative to the control will provide an average hazard ratio (HR) for the clinical endpoint of 0·68, and 95% of sufficiently large studies would have HRs between 0·47 and 0·95. Interpretation Our results support a role for change in albuminuria as a surrogate endpoint for the progression of chronic kidney disease, particularly in patients with high baseline albuminuria; for patients with low baseline levels of albuminuria this association is less certain

Validation of the CO2/N2O Analogy using Molecular Simulation

CO2 readily reacts in aqueous amine solutions. The properties of free CO2 in amine solutions are therefore difficult to obtain directly and are often predicted from the nonreacting molecule N2O due to the similarities in mass and structure. This often-used empirical "CO2/N2O analogy" is verified in this work using molecular simulation. Continuous fractional component Monte Carlo (CFCMC) simulations in the osmotic ensemble were used to compute the Henry coefficients of CO2 and N2O in the solvents water, ethanol, n-heptane, and a 30% aqueous MEA solution at a temperature of 303 K. Molecular dynamics (MD) simulations were performed to compute the self-diffusivities of CO2 and N2O in the aforementioned solvents at 303 K. Different force fields for CO2 and water were used. The computed Henry coefficients and self-diffusivities of CO2 and N2O in the solvents are in good agreement with available experimental data. The simulation results indicate that the CO2/N2O analogy is valid for aqueous MEA solution at 303 K. The Henry coefficient and self-diffusivity ratios of CO2 to N2O in water and 30% MEA solution are approximately 0.77 and 1.1, respectively. Additional simulations where all the amines have reacted with CO2 confirm that reactions have little impact on the physical absorption and diffusion properties of CO2

IgA Nephropathy Is the Most Common Underlying Disease in Patients With Anticoagulant-Related Nephropathy

Introduction Anticoagulant-related nephropathy (ARN) is a relatively novel recognized entity characterized by hematuria-associated acute kidney injury (AKI) in the context of overanticoagulation. Preexisting or underlying kidney disease seems to be a predisposing factor; however, few studies have described histologic findings in patients with ARN. We aimed to evaluate underlying kidney pathology in patients on oral anticoagulation who presented an episode of AKI with hematuria in whom a kidney biopsy was performed. Methods Retrospective observational multicenter case study in patients treated with oral anticoagulants who developed macroscopic or intense hematuria followed by AKI. Only patients with available kidney biopsy specimens were included. Histologic findings and clinical data throughout follow-up were analyzed. Results A total of 26 patients were included with a median age of 75 years (62–80) and a follow-up period of 10.1 months. Of the patients, 80% were male, and most cases (92%) were on anticoagulation with vitamin K antagonists (VKAs). At admission, median serum creatinine (SCr) level was 4.2 mg/dl (2.8–8.2), median international normalized ratio (INR) 2.4 (1.5–3.4), and 11 patients (42%) required acute dialysis during hospitalization. Kidney biopsy results revealed that all patients except 1 had an underlying nephropathy: IgA nephropathy (IgAN) in 19, probable IgAN in 1, diabetic nephropathy in 3, nephrosclerosis in 1, and idiopathic nodular glomerulosclerosis in 1. At 12 weeks after discharge, only 6 subjects (24%) attained complete kidney recovery whereas 7 (28%) remained on chronic dialysis. Conclusion IgAN was the most common underlying kidney disease in our biopsy-proven series of ARN, in which a significant percentage of patients did not achieve kidney function recovery

Metastable Zr/Hf-MOFs: The hexagonal family of EHU-30 and their water-sorption induced structural transformation

UiO-66, reported in 2008, inspired the ongoing chemistry of group 4 metal-organic frameworks and it is still one of the most studied MOFs due to its exceptional stability. The tightness of their building blocks and bond strength make it tough to access new topologies, unless the building blocks are changed or defect engineering is employed, which in turn lead to different nominal stoichiometries. However, well selected structure directing agents and harsh synthesis conditions allowed the isolation of the first polymorph of UiO-66, named EHU-30. Herein, we provide evidence for the generalization of the synthetic approach with four new EHU-30 isoreticular compounds, based on amino-functionalized linkers and zirconium and hafnium as metal centres: EHU-30-NH2(M) and EHU-30-NHR(M) (M: Zr, Hf; R: 2-carboxypropyl). The crystal structure analysis reveals that their framework is more porous than that of their polymorphic counterpart. Furthermore, due to the current relevance of MOFs in greenhouse gas capture and in water harvesting methodologies, we have explored CO2 and water vapour adsorption on the new polymorphic phases, by means of experimental and computational resources, and compared to the parent EHU-30. The amino functionalization makes the EHU-30 series more prone to CO2 and water vapour adsorption. Besides, the water adsorption isotherms show an interesting crossing sensitive to temperature, sorption cycles and functionalization of the linker, which has been attributed to a localized structural transformation from EHU-30 to UiO-66. Finally, time-of-flight (TOF) powder neutron diffraction experiments were also conducted to locate the preferred adsorption sites for water in functionalized and parent EHU-30 structures

Understanding Adsorption of Highly Polar Vapors on Mesoporous MIL-100(Cr) and MIL-101(Cr): Experiments and Molecular Simulations

The adsorption of polar water and methanol vapors on the meso- and microporous metal–organic frameworks (MOFs) MIL-100­(Cr) and MIL-101­(Cr) has been studied by a combined experimental and simulation approach. The computational effort for these MOFs with large unit cells was reduced by using primitive unit cells that were 4 times smaller. Our results demonstrate that both adsorbate–adsorbent and adsorbate–adsorbate interactions control the adsorption process. At low loadings, before all coordinatively unsaturated chromium sites are occupied, the MOF structure determines the shape of the isotherm, and the molecular model for the polar sorbate is less important. A clear difference was found between fully fluorinated and hydroxylated MIL-101 structures for both methanol and water, demonstrating that partial charges on Cr drive the initial shape of the isotherm. At higher loadings, adsorbate–adsorbate interactions become much more important, and the choice of the water model, in particular, is crucial for the agreement between experimental and simulation results. The simplest SPC/E model reproduces the experimental results with the best accuracy, in contrast to more advanced models such as TIP5PEw, which can be explained by the slightly stronger Coulombic interactions predicted by the former. For methanol, the general TraPPE force field performs well. A composite type IV isotherm for methanol and a composite type V isotherm for water, according to the IUPAC classification, were found. The heats of adsorption are in line with these conclusions. To the best of our knowledge, this effect of the sorbate model has not been observed in adsorption in microporous materials, and it highlights the complexity behind molecular simulations in periodic mesostructured materials