bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extended beta distributions open the access to fast gating in bilayer experiments—assigning the voltage‐dependent gating to the selectivity filter
Authors: Rauh Oliver , Hansen Ulf‐Peter , Mach Sebastian , Hartel Andreas J.W. , Shepard Kenneth L. , Thiel Gerhard , Schroeder Indra 
Published: November 2017

Lipid bilayers provide many benefits for ion channel recordings, such as control of membrane composition and transport molecules. However, they suffer from high membrane capacitance limiting the bandwidth and impeding analysis of fast gating. This can be overcome by fitting the deviations of the open‐channel noise from the baseline noise by extended beta distributions. We demonstrate this analysis step‐by‐step by applying it to the example of viral K+ channels (Kcv), from the choice of the gating model through the fitting process, validation of the results, and what kinds of results can be obtained. These voltage sensor‐less channels show profoundly voltage‐dependent gating with dwell times in the closed state of about 50 μs. Mutations assign it to the selectivity filter.
The Plasma Sheet as Natural Symmetry Plane for Dipolarization Fronts in the Earth's Magnetotail
Authors: Frühauff D. , Glassmeier K.‐H. 
Published: November 2017

AbstractIn this work, observations of multispacecraft mission Time History of Events and Macroscale Interactions during Substorms are used for statistical investigation of dipolarization fronts in the near‐Earth plasma sheet of the magnetotail. Using very stringent criteria, 460 events are detected in almost 10 years of mission data. Minimum variance analysis is used to determine the normal directions of the phase fronts, providing evidence for the existence of a natural symmetry of these phenomena, given by the neutral sheet of the magnetotail. This finding enables the definition of a local coordinate system based on the Tsyganenko model, reflecting the intrinsic orientation of the neutral sheet and, therefore, the dipolarization fronts. In this way, the comparison of events with very different background conditions is improved. Through this study, the statistical results of Liu, Angelopoulos, Runov, et al. (2013) are both confirmed and extended. In a case study, the knowledge of this plane of symmetry helps to explain the concave curvature of dipolarization fronts in the XZ plane through phase propagation speeds of magnetoacoustic waves. A second case study is presented to determine the central current system of a passing dipolarization front through a constellation of three spacecraft. With this information, a statistical analysis of spacecraft observations above and below the neutral sheet is used to provide further evidence for the neutral sheet as the symmetry plane and the central current system. Furthermore, it is shown that the signatures of dipolarization fronts are under certain conditions closely related to that of flux ropes, indicating a possible relationship between these two transient phenomena.
Ellipsoidal Correction in GRACE Surface Mass Change Estimation
Authors: Li Jin , Chen Jianli , Li Ziang , Wang Song‐Yun , Hu Xiaogong 
Published: November 2017

AbstractThe Earth's shape is much closer to an ellipsoid than a sphere. The commonly used spherical approximation in mass change inversion is expected to cause bias by the spherical harmonic (SH) solutions from Gravity Recovery and Climate Experiment (GRACE), especially in high‐latitude regions where significant present‐day ice losses occur. This bias, or ellipsoidal correction, reaches up to 8% from the evaluation by simulations based on synthetic mass change rate models. Further evaluation using 14 plus years of GRACE monthly SH solutions (from April 2002 to December 2016) indicates that the ellipsoidal correction is also noticeable in the total mass change time series over polar regions. Before and after the ellipsoidal correction, the estimated linear rates from mass change time series differ by 4.3%, 4.7%, 5.2%, 5.7%, and 6.6% for five selected regions over Greenland, Antarctic Peninsula, Amundsen Sea Embayment, Alaska glacier, and Svalbard Islands, respectively. Although with amplitudes likely below the current GRACE's uncertainty level, these differences are consistently negative over the five regions. This indicates that the spherical approximation leads to systematic underestimation for polar mass change rates. Thus, the ellipsoidal correction needs to be considered for more precise mass recovery with GRACE SH solutions. It also depends on spatial scales of mass change signals (the smaller the spatial scale, the larger the correction). To more reliably estimate high‐latitude surface mass changes by GRACE SH solutions, the ellipsoidal correction is recommended, especially for ice‐loss signals over polar regions.
First Simulations of Designing Stratospheric Sulfate Aerosol Geoengineering to Meet Multiple Simultaneous Climate Objectives
Authors: Kravitz Ben , MacMartin Douglas G. , Mills Michael J. , Richter Jadwiga H. , Tilmes Simone , Lamarque Jean‐Francois , Tribbia Joseph J. , Vitt Francis 
Published: November 2017

AbstractWe describe the first simulations of stratospheric sulfate aerosol geoengineering using multiple injection locations to meet multiple simultaneous surface temperature objectives. Simulations were performed using CESM1(WACCM), a coupled atmosphere‐ocean general circulation model with fully interactive stratospheric chemistry, dynamics (including an internally generated quasi‐biennial oscillation), and a sophisticated treatment of sulfate aerosol formation, microphysical growth, and deposition. The objectives are defined as maintaining three temperature features at their 2020 levels against a background of the RCP8.5 scenario over the period 2020–2099. These objectives are met using a feedback mechanism in which the rate of sulfur dioxide injection at each of the four locations is adjusted independently every year of simulation. Even in the presence of uncertainties, nonlinearities, and variability, the objectives are met, predominantly by SO2 injection at 30°N and 30°S. By the last year of simulation, the feedback algorithm calls for a total injection rate of 51 Tg SO2 per year. The injections are not in the tropics, which results in a greater degree of linearity of the surface climate response with injection amount than has been found in many previous studies using injection at the equator. Because the objectives are defined in terms of annual mean temperature, the required geongineering results in “overcooling” during summer and “undercooling” during winter. The hydrological cycle is also suppressed as compared to the reference values corresponding to the year 2020. The demonstration we describe in this study is an important step toward understanding what geoengineering can do and what it cannot do.
Sensitivity of Aerosol Distribution and Climate Response to Stratospheric SO2 Injection Locations
Authors: Tilmes Simone , Richter Jadwiga H. , Mills Michael J. , Kravitz Ben , MacMartin Douglas G. , Vitt Francis , Tribbia Joseph J. , Lamarque Jean‐Francois 
Published: November 2017

AbstractInjection of SO2 into the stratosphere has been proposed as a method to, in part, counteract anthropogenic climate change. So far, most studies investigated injections at the equator or in a region in the tropics. Here we use Community Earth System Model version 1 Whole Atmosphere Community Climate Model (CESM1(WACCM)) to explore the impact of continuous single grid point SO2 injections at seven different latitudes and two altitudes in the stratosphere on aerosol distribution and climate. For each of the 14 locations, 3 different constant SO2 emission rates were tested to identify linearity in aerosol burden, aerosol optical depth, and climate effects. We found that injections at 15°N and 15°S and at 25 km altitude have equal or greater effect on radiation and surface temperature than injections at the equator. Nonequatorial injections transport SO2 and sulfate aerosols more efficiently into middle and high latitudes and result in particles of smaller effective radius and larger aerosol burden in middle and high latitudes. Injections at 15°S produce the largest increase in global average aerosol optical depth and increase the change in radiative forcing per Tg SO2/yr by about 15% compared to equatorial injections. High‐altitude injections at 15°N produce the largest reduction in global average temperature of 0.2° per Tg S/yr for the last 7 years of a 10 year experiment. Injections at higher altitude are generally more efficient at reducing surface temperature, with the exception of large equatorial injections of at least 12 Tg SO2/yr. These findings have important implications for designing a strategy to counteract global climate change.
Creating Aerosol Types from CHemistry (CATCH): A New Algorithm to Extend the Link Between Remote Sensing and Models
Authors: Dawson K. W. , Meskhidze N. , Burton S. P. , Johnson M. S. , Kacenelenbogen M. S. , Hostetler C. A. , Hu Y. 
Published: November 2017

AbstractCurrent remote sensing methods can identify aerosol types within an atmospheric column, presenting an opportunity to incrementally bridge the gap between remote sensing and models. Here a new algorithm was designed for Creating Aerosol Types from CHemistry (CATCH). CATCH‐derived aerosol types—dusty mix, maritime, urban, smoke, and fresh smoke—are based on first‐generation airborne High Spectral Resolution Lidar (HSRL‐1) retrievals during the Ship‐Aircraft Bio‐Optical Research (SABOR) campaign, July/August 2014. CATCH is designed to derive aerosol types from model output of chemical composition. CATCH‐derived aerosol types are determined by multivariate clustering of model‐calculated variables that have been trained using retrievals of aerosol types from HSRL‐1. CATCH‐derived aerosol types (with the exception of smoke) compare well with HSRL‐1 retrievals during SABOR with an average difference in aerosol optical depth (AOD) <0.03. Data analysis shows that episodic free tropospheric transport of smoke is underpredicted by the Goddard Earth Observing System‐ with Chemistry (GEOS‐Chem) model. Spatial distributions of CATCH‐derived aerosol types for the North American model domain during July/August 2014 show that aerosol type‐specific AOD values occurred over representative locations: urban over areas with large population, maritime over oceans, smoke, and fresh smoke over typical biomass burning regions. This study demonstrates that model‐generated information on aerosol chemical composition can be translated into aerosol types analogous to those retrieved from remote sensing methods. In the future, spaceborne HSRL‐1 and CATCH can be used to gain insight into chemical composition of aerosol types, reducing uncertainties in estimates of aerosol radiative forcing.
Radiative and Chemical Response to Interactive Stratospheric Sulfate Aerosols in Fully Coupled CESM1(WACCM)
Authors: Mills Michael J. , Richter Jadwiga H. , Tilmes Simone , Kravitz Ben , MacMartin Douglas G. , Glanville Anne A. , Tribbia Joseph J. , Lamarque Jean‐François , Vitt Francis , Schmidt Anja , Gettelman Andrew , Hannay Cecile , Bacmeister Julio T. , Kinnison Douglas E. 
Published: November 2017

AbstractWe present new insights into the evolution and interactions of stratospheric aerosol using an updated version of the Whole Atmosphere Community Climate Model (WACCM). Improved horizontal resolution, dynamics, and chemistry now produce an internally generated quasi‐biennial oscillation and significant improvements to stratospheric temperatures and ozone compared to observations. We present a validation of WACCM column ozone and climate calculations against observations. The prognostic treatment of stratospheric sulfate aerosols accurately represents the evolution of stratospheric aerosol optical depth and perturbations to solar and longwave radiation following the June 1991 eruption of Mount Pinatubo. We confirm the inclusion of interactive OH chemistry as an important factor in the formation and initial distribution of aerosol following large inputs of sulfur dioxide (SO2) to the stratosphere. We calculate that depletion of OH levels within the dense SO2 cloud in the first weeks following the Pinatubo eruption significantly prolonged the average initial e‐folding decay time for SO2 oxidation to 47 days. Previous observational and model studies showing a 30 day decay time have not accounted for the large (30–55%) losses of SO2 on ash and ice within 7–9 days posteruption and have not correctly accounted for OH depletion. We examine the variability of aerosol evolution in free‐running climate simulations due to meteorology, with comparison to simulations nudged with specified dynamics. We assess calculated impacts of volcanic aerosols on ozone loss with comparisons to observations. The completeness of the chemistry, dynamics, and aerosol microphysics in WACCM qualify it for studies of stratospheric sulfate aerosol geoengineering.
Reply to Comment on “Radiative Transfer in CO2‐Rich Atmospheres: 1. Collisional Line Mixing Implies a Colder Early Mars”
Authors: Ozak N. , Aharonson O. , Halevy I. 
Published: November 2017

AbstractTurbet and Tran (2017) have identified that we mistakenly used air‐broadened CO2 absorption spectra to generate coefficients for a rapid radiative transfer code, instead of self‐broadened spectra. The resulting underestimation of absorption by CO2 led us to suggest that when the effects of CO2 line mixing are taken into account, surface temperatures on early Mars are up to 15 K colder than those calculated in previous studies, in which empirical corrections of the CO2 spectrum were used (χ factors). Using the correct CO2 absorption spectra, including the effects of line mixing, Turbet and Tran (2017) found that the surface temperature is colder by only 2 K than temperatures calculated with the χ factor approach. While we acknowledge the mistake, and thank Turbet and Tran (2017) for finding and correcting it, we note that our main conclusions hold that surface temperatures are overestimated when empirical χ factors are used instead of a full account of CO2 line mixing in radiative transfer calculations in CO2‐rich planetary atmospheres. Additionally, we emphasize that the rapid radiative transfer model we developed and tested is useful for studies of planetary climate, provided the correct absorption spectra are used to generate new k coefficients.
Linkage Analysis
Authors: Shao Yongzhao 
Published: November 2017

AbstractLinkage analysis is an important initial step in localizing and identifying genes in the chromosomes that underlie many human diseases and other traits of interest. Frequently, genetic linkage analysis proceeds by comparing the inheritance pattern of the trait and that of the genetic markers to establish linkage between the trait and marker loci where family (or pedigree)‐based study designs are often of great importance. In the past two decades, linkage analysis‐based gene mapping has largely been supplanted by the population‐based genome‐wide association study (GWAS) based on single‐nucleotide polymorphisms (SNPs). The rapid development and increased adoption of next‐generation whole‐genome sequencing (WGS) has revived linkage analysis and family‐based studies for the identification and characterization of functional variants including rare variants. This article provides a brief overview of commonly used methods for linkage analysis, which include model‐free and model‐based methods for mapping qualitative‐ and quantitative‐trait loci. Linkage analysis methods suitable under locus heterogeneity are reviewed. Linkage analysis methods that utilize both IBD allele sharing information and LD information as well as genome‐wide linkage analysis are discussed. Issues on the design of linkage studies are also briefly discussed.
Within‐Case Designs: Distribution‐Free Methods
Authors: Lix Lisa M. 
Published: November 2017

AbstractIn within‐case designs, individuals are measured repeatedly over time or across multiple experimental conditions. Univariate and multivariate parametric procedures for testing within‐case effects may lose statistical power under departures from a multivariate normal distribution. Nonparametric procedures based on rank scores or bootstrapping are useful alternatives for testing within‐case effects when the data are skewed or have heavy tails. We consider these methods when there are missing observations and for complex designs.
Intention‐to‐Treat: Overview
Authors: Lachin John M. 
Published: November 2017

AbstractThe intention‐to‐treat principle developed from concerns that an analysis of a subset of subjects entered into a clinical trial may provide a severely biased estimate of the expected outcome in all subjects for whom a treatment might be administered. Theintention‐to‐treat analysisincludes all data from all subjects randomized into the study to provide a pragmatic assessment of the effects of therapy, regardless of drug tolerability or compliance. This approach is contrasted with an analysis of a subset, such as a “per protocol” analysis that only includes participants that tolerated the assigned agent, who were largely compliant, and who completed follow‐up.Therefore, a true intention‐to‐treat analysis requires anintention‐to‐treat designin which all those randomized are expected to complete follow‐up assessments to the extent possible, even if no longer taking the drug, and their data should be employed in the analysis.Many statistical methods can provide an unbiased comparison of treatment effects when all missing observations are ignorable, that is, no bias is introduced. However, this assumption is inherently unverifiable. Thus, the only incontrovertibly unbiased study is one in which all randomized patients are evaluated and included in the analysis, assuming that other features of the study are also unbiased. This design is the essence of the intent‐to‐treat philosophy.
Bivariate Distributions
Authors: Christman Mary C. 
Published: November 2017

Abstract

Bivariate distributions play a special role in environmental science as they are the underpinnings of analyses of relationships between two random variables. These relationships include analyses such as biserial correlation between continuous and discrete random variables, measures of association in an
r
×
c
contingency table, Pearson's product–moment correlation, Kendall's tau, Spearman's rank correlation, and many others. In addition to the studies of the dependency between two variables, interest may center on other analyses; for example, multivariate general (or generalized) linear modeling when two or more response variables are involved. Inferences involving two random variables rely on knowledge of their bivariate distribution. Probably, the best‐known example is estimation and testing of the correlation coefficient in the bivariate normal distribution for two continuous random variables. There are many other distributions of importance as well, especially those relating two discrete random variables or a discrete to a continuous variable. This article describes a few of the more common distributions in environmental practice and, where appropriate, mentions the multivariate distribution of which the bivariate is a special case.
Project Management in Government
Authors: Khamooshi Homayoun 
Published: November 2017

AbstractGovernment project management (GPM) environment normally has more uncertainties and complexities associated with it than nongovernment project environment. As such, a more robust and rigorous project management approach is needed for successful delivery of products (deliverable) and benefits. In addition, usually government projects are outsourced rather than delivered and managed in‐house. This implies that GPM is all about governance. When it comes to governance, government project managers need to be deeply involved in the management of these projects. First and foremost, a veryrobust governance structuremust be put in place, making sure that components of the structures are fully functional and engaged in the supervision of the project execution. The second important issue isfront end planning (FEP). It is the government's responsibility to have a deep understanding of the scope of project, the required budget, and the risks associated with the project. The FEP, along with continuous engagement of the governance team over the phases of project, paves the way for successful delivery. Finally, to be successful, the government project managers should focus onfive KPIs(key performance indicators), namely, scope management, quality management, time management, cost management, and risk management. This article addresses these critical success factors and their dynamic relationship in GPM environment.
Hall,PeterG
Authors: Robinson John , Welsh Alan H. 
Published: November 2017

AbstractPeter Hall was an Australian probabilist and mathematical statistician who, in an incredibly productive career, contributed both widely and deeply to martingale limit theory, rates of convergence in the central limit theorem, extreme value theory, coverage processes, the bootstrap, and, in its widest sense, nonparametric function estimation. In addition to his productivity, he was renowned for his technical skill and intuition in developing and applying mathematical methods to a wide range of problems. He was an active member of the international community and a leading advocate for mathematics and statistics in Australia.
Genetic Aspects of Seed Dormancy
Authors: Bentsink Leónie , Soppe Wim , Koornneef Maarten 
Published: November 2017

AbstractThe sections in this article areIntroductionMutant Approaches inArabidopsisMutant Approaches in Other SpeciesGenetic Analyses of Natural VariationWhat Do the Genetics Teach Us about Dormancy and Germination?
Regulation ofABAandGALevels during Seed Development and Germination inArabidopsis
Authors: Yamaguchi Shinjiro , Kamiya Yuji , Nambara Eiji 
Published: November 2017

AbstractThe sections in this article areIntroductionBiosynthetic and Deactivation Pathways ofABAandGAInhibitors ofABAandGAMetabolism: Efficacy and Side Effects of DrugsRegulation ofABAandGALevels inArabidopsis SeedsConclusions and Perspectives
Chromatin Remodeling and Histone Variants in Transcriptional Regulation and in MaintainingDNAMethylation
Authors: Reyes J.C. , Brzeski J. , Jerzmanowski A. 
Published: November 2017

AbstractThe sections in this article areIntroductionATP‐Dependent Chromatin RemodelingChromatin Remodeling andDNAMethylationHistone Variants in the Regulation of Chromatin Functions
Perovskite Solar Cells with ZnO Electron‐Transporting Materials
Authors: Zhang Peng , Wu Jiang , Zhang Ting , Wang Yafei , Liu Detao , Chen Hao , Ji Long , Liu Chunhua , Ahmad Waseem , Chen Zhi David , Li Shibin 
Published: November 2017

AbstractPerovskite solar cells (PSCs) have developed rapidly over the past few years, and the power conversion efficiency of PSCs has exceeded 20%. Such high performance can be attributed to the unique properties of perovskite materials, such as high absorption over the visible range and long diffusion length. Due to the different diffusion lengths of holes and electrons, electron transporting materials (ETMs) used in PSCs play a critical role in PSCs performance. As an alternative to TiO2 ETM, ZnO materials have similar physical properties to TiO2 but with much higher electron mobility. In addition, there are many simple and facile methods to fabricate ZnO nanomaterials with low cost and energy consumption. This review focuses on recent developments in the use of ZnO ETM for PSCs. The fabrication methods of ZnO materials are briefly introduced. The influence of different ZnO ETMs on performance of PSCs is then reviewed. The limitations of ZnO ETM‐based PSCs and some solutions to these challenges are also discussed. The review provides a systematic and comprehensive understanding of the influence of different ZnO ETMs on PSCs performance and potentially motivates further development of PSCs by extending the knowledge of ZnO‐based PSCs to TiO2‐based PSCs.