bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling thermal emissive bands radiometric calibration impact with application to AVHRR
Authors: Chang Tiejun , Wu Xiangqian , Weng Fuzhong 
Published: February 2017

AbstractA novel analytical model of the calibration error impact on the Earth radiance measurement from thermal emissive bands of sensors is developed. The goal is to assess the impact of calibration errors, to evaluate those errors and to perform correction. This model is applied in the correction of bias in Advanced Very High Resolution Radiometer (AVHRR) channels 4 and 5 observed from the intercomparison with Infrared Atmospheric Sounding Interferometer measurements. A two‐step regression is used to separate the effects of calibration radiance errors from calibration coefficient errors. In the first step, the calibration radiance error, primarily due to internal calibration target (ICT) imperfections and temperature measurement error, is evaluated using the bias from selected Earth scenes with brightness temperatures close to the ICT temperature. The effects from the ICT imperfections and temperature measurement errors are analyzed collectively. The resulting estimation of the calibration radiance error is 0.30% for channel 4 and 0.33% for channel 5. After correcting the Earth scene radiance for these effects, the errors in the offset and nonlinear coefficient of instrument response are evaluated through the second step of the regression. A weighting function is used to account for the nonuniformity in the data distribution over the Earth radiance range. After the evaluation of the errors, removal of their effects can be achieved either through corrections of the calibration coefficients or correction of the measured radiance. The results are useful for the improvement of the AVHRR IR channel calibration algorithm. This model and two‐step regression approach can also be applied to other similar broadband thermal infrared radiometric sensors.
Closing the scale gap between land surface parameterizations and GCMs with a new scheme, SiB3‐Bins
Authors: Baker I. T. , Sellers P. J. , Denning A. S. , Medina I. , Kraus P. , Haynes K. D. , Biraud S. C. 
Published: February 2017

AbstractThe interaction of land with the atmosphere is sensitive to soil moisture (W). Evapotranspiration (ET) reacts to soil moisture in a nonlinear way, f(W), as soils dry from saturation to wilt point. This nonlinear behavior and the fact that soil moisture varies on scales as small as 1–10 m in nature, while numerical general circulation models (GCMs) have grid cell sizes on the order of 1 to 100s of kilometers, makes the calculation of grid cell‐average ET problematic. It is impractical to simulate the land in GCMs on the small scales seen in nature, so techniques have been developed to represent subgrid scale heterogeneity, including: (1) statistical‐dynamical representations of grid subelements of varying wetness, (2) relaxation of f(W), (3) moderating f(W) with approximations of catchment hydrology, (4) “tiling” the landscape into vegetation types, and (5) hyperresolution. Here we present an alternative method for representing subgrid variability in W, one proven in a conceptual framework where landscape‐scale W is represented as a series of “Bins” of increasing wetness from dry to saturated. The grid cell‐level f(W) is defined by the integral of the fractional area of the wetness bins and the value of f(W) associated with each. This approach accounts for the spatiotemporal dynamics of W. We implemented this approach in the SiB3 land surface parameterization and then evaluated its performance against a control, which assumes a horizontally uniform field of W. We demonstrate that the Bins method, with a physical basis, attenuates unrealistic jumps in model state and ET seen in the control runs.
Understanding watershed hydrogeochemistry: 2. Synchronized hydrological and geochemical processes drive stream chemostatic behavior
Authors: Li Li , Bao Chen , Sullivan Pamela L. , Brantley Susan , Shi Yuning , Duffy Christopher 
Published: February 2017

AbstractWhy do solute concentrations in streams remain largely constant while discharge varies by orders of magnitude? We used a new hydrological land surface and reactive transport code, RT‐Flux‐PIHM, to understand this long‐standing puzzle. We focus on the nonreactive chloride (Cl) and reactive magnesium (Mg) in the Susquehanna Shale Hills Critical Zone Observatory (SSHCZO). Simulation results show that stream discharge comes from surface runoff (Qs), soil lateral flow (QL), and deeper groundwater (QG), with QL contributing >70%. In the summer, when high evapotranspiration dries up and disconnects most of the watershed from the stream, Cl is trapped along planar hillslopes. Successive rainfalls connect the watershed and mobilize trapped Cl, which counteracts dilution effects brought about by high water storage (Vw) and maintains chemostasis. Similarly, the synchronous response of clay dissolution rates (Mg source) to hydrological conditions, maintained largely by a relatively constant ratio between “wetted” mineral surface area Aw and Vw, controls Mg chemostatic behavior. Sensitivity analysis indicates that cation exchange plays a secondary role in determining chemostasis compared to clay dissolution, although it does store an order‐of‐magnitude more Mg on exchange sites than soil water. Model simulations indicate that dilution (concentration decrease with increasing discharge) occurs only when mass influxes from soil lateral flow are negligible (e.g., via having low clay surface area) so that stream discharge is dominated by relatively constant mass fluxes from deep groundwater that are unresponsive to surface hydrological conditions.
A cellular automata‐based deterministic inversion algorithm for the characterization of linear structural heterogeneities
Authors: Fischer P. , Jardani A. , Lecoq N. 
Published: February 2017

AbstractInverse problem permits to map the subsurface properties from a few observed data. The inverse problem can be physically constrained by a priori information on the property distribution in order to limit the nonuniqueness of the solution. The geostatistical information is often chosen as a priori information; however, when the field properties present a spatial locally distributed high variability, the geostatistical approach becomes inefficient. Therefore, we propose a new method adapted for fields presenting linear structures (such as a fractured field). The Cellular Automata‐based Deterministic Inversion (CADI) method is, as far as we know when this paper is produced, the first inversion method which permits a deterministic inversion based on a Bayesian approach and using a dynamic optimization to generate different linear structures iteratively. The model is partitioned in cellular automaton subspaces, each one controlling a different zone of the model. A cellular automata subspace structures the properties of the model in two units (“structure” and “background”) and control their dispensing direction and their values. The partitioning of the model in subspaces permits to monitor a large‐scale structural model with only a few pilot‐parameters and to generate linear structures with local direction changes. Thereby, the algorithm can easily handle with large‐scale structures, and a sensitivity analysis is possible on these structural pilot‐parameters, which permits to considerably accelerate the optimization process in order to find the best structural geometry. The algorithm has been successfully tested on simple, to more complex, theoretical models with different inversion techniques by using seismic and hydraulic data.
Response of the lower troposphere to moisture intrusions into the Arctic
Authors: Johansson Erik , Devasthale Abhay , Tjernström Michael , Ekman Annica M. L. , L'Ecuyer Tristan 
Published: February 2017

AbstractWater vapor intrusions (WVIs) explain a significant fraction of total moisture transport and its variability in the Arctic. WVIs can precondition the Arctic atmosphere for accelerated melting of sea ice through effects on surface longwave radiation. Using data from the NASA's A‐Train convoy of satellites to estimate the response of the lower troposphere to WVIs into the Arctic, we show that WVIs are associated with a surface warming of up to 5.3 K (±3.3 K) in winter and 2.3 K (±1.6 K) in summer, when averaged over the entire Arctic Ocean. The intrusions also lead to additional cloud radiative heating of up to 0.15 K/d via up to 30% increased cloudiness in the vertical and also cause a weakening of the stability in the lower troposphere. The lower tropospheric and surface warming during winter and spring highlights the importance of understanding contribution of preconditioning to accelerated ice melt in the Arctic.
Messenger
RNA
Splicing Signals
Authors: Cygan Kamil J , Taggart Allison J , Fairbrother William G , Mount Stephen M 
Published: February 2017

Abstract

Splicing is a post‐transcriptional processing step in which intervening sequences (introns) are excised and coding sequences (exons) are ligated together to create the mature mRNA (messenger ribonucleic acid) molecule. It is a sequential process that is facilitated by the information in the RNA (ribonucleic acid) sequence (splicing regulatory elements/signals) and numerous RNA‐binding proteins (trans factors). Splicing occurs through two biochemical steps, and is catalysed by a large ribonucleoprotein known as the spliceosome. The spliceosomal machinery recognises the core splicing signals and assembles in a stepwise fashion on the premRNA molecule. These signals include the obligate 5′ splice site, 3′ splice site and branch site sequence, as well as enhancer and silencer sequences which functionally interact with RNA binding proteins. A current research application in the field uses computational approaches to study splicing signals and predict the effect of single nucleotide variations on message processing.

Key Concepts

Splicing is a post‐transcriptional process in which certain sections of RNA (known as introns) are removed and other sections (known as exons) are ligated together, producing the mature mRNA molecule.

Splicing is catalysed by a large macromolecular machine known as the spliceosome.

The major elements required for splicing include the 5′ splice site (5′ss), the 3′ splice site (3′ss), the polypyrimidine tract and the branch site.

Most introns begin with a ‘GT’ sequence and end with an ‘AG’ sequence; however, there exists a class of intron with different boundary sequences that are recognised by a parallel spliceosome.

Outside of these major elements, there are additional enhancer and suppressor signals that interact with RNA‐binding proteins (RBPs) and affect splicing outcome.

Different combinations and positions of binding of RBPs can result in different splicing outcome.

Scientists do not yet have a complete understanding of all of the different splicing signals, and this topic is an area of active research.

Researchers are using computational machine learning approaches to predict the effects of sequence variation on splicing outcome.

Researchers are also using new methods of sequencing to determine which RNA sequences the RBPs are recognising.
Seabird Island Ecology
Authors: Anderson Wendy B , Mulder Christa PH , Ellis Julie C 
Published: February 2017

Abstract

Seabird islands house large colonies of seabirds that feed at sea but return to land to breed. Seabirds deposit large amounts of nutrients of marine origin onto islands; many species also disturb soil and vegetation during the building and maintenance of nests. Nutrient subsidies and physical disturbance by seabirds alter island soils and vegetation and modify plant and animal communities. Introduction of non‐native predators has resulted in population decreases or local extinction of many seabird species. Recent efforts at eradication of introduced seabird predators have been successful, but re‐establishment of seabirds and seabird island communities will likely take additional active restoration. Many other factors impact seabird populations such as overfishing, seabirds caught as by‐catch, increases in sea surface temperature, sea level rise, and various sorts of marine pollution, including plastics consumed by seabirds. These factors directly and indirectly affect the ecology of seabird islands.

Key Concepts

Seabirds deposit nutrients of marine origin in terrestrial environments.

Seabirds impose physical disturbance on soils and vegetation in the process of building and maintaining nests.

Seabird islands often house endemic and native plants and animals that are no longer found on the mainland.

The presence of seabirds selects for plants that are tolerant of high‐disturbance and high‐nutrient (i.e. nitrogen and phosphorus) conditions and that increase primary and secondary productivity.

Introduced mammalian predators have eradicated seabirds and other species on many seabird islands.

The reduction of seabird populations by introduced predators alters plant and animal communities and nutrient cycling.

Eradication of seabird predators is a necessary first step towards restoration of seabird islands.

Restoration of seabird islands often requires active management of seabirds, other animals and plant populations.

Protection of seabird islands will require international cooperation on land and at sea.

Several marine environmental issues impact seabird populations and thus also the island communities that are tightly associated with seabird presence.
Testing Children for Genetic Carrier Status
Authors: Vears Danya F 
Published: February 2017

Abstract

A number of studies have shown that some parents of children with a genetic condition are interested in knowing the carrier status of their other, unaffected children. The majority of international guidelines suggest that carrier testing in childhood is inappropriate and should be delayed until the child reaches the age of majority. These recommendations are often based on theoretical concerns and ethical considerations as there is a lack of evidence in the literature that performing carrier testing in childhood leads to any psychosocial harm. There is also evidence that carrier testing does take place in some circumstances. The different guidelines and position statements of professional bodies regarding carrier testing in childhood are reviewed. The views of both health professionals and parents about whether carrier testing is appropriate are described, along with the current evidence regarding the psychosocial impacts of performing carrier testing in children.

Key Concepts

The majority of international guidelines recommend against carrier testing in childhood.

Despite the guidelines, carrier testing does take place in some children in the context of an affected sibling.

Health professionals' willingness to test children for carrier status depends on a range of different factors, including the genetic condition.

Some parents want to know the carrier status of their unaffected children following the diagnosis of an affected child.

Parents express a range of motivations for desiring this information, although many want to communicate the carrier information to their child.

Currently there is no evidence of harm from performing carrier testing in childhood, although further research is warranted.
Conjugate Families of Distributions
Authors: Chakraborty Sayan , Maiti Tapabrata 
Published: February 2017

AbstractThe idea of a parameterized family of probability distributions conjugate to a given sampling process was proposed by Raiffa and Schlaifer in their influential monograph. Their work was based largely on exploring the benefits of conjugacy, which include mathematically tractable closed‐form expressions for many important quantities used in Bayesian inference and decision analysis. When statistical data are to be analyzed in Bayesian theory, a “prior” distribution must be chosen to model a person's belief concerning unknown parameters in the sampling process. The modeled uncertainty is that which exists prior to observation of the statistical data. There is no sense of innate a “priori” knowledge, or knowledge based on pure logical reasoning free of experience. Previous statistical data, for example, may be considered when choosing a prior distribution. If a conjugate family is rich enough, a prior distribution chosen from the family can provide a useful approximation to the actual considered opinion.
Stratified Sampling
Authors: Parsons Van L. 
Published: February 2017

Abstract
Stratified sampling is a probability sampling method that is implemented in sample surveys. The target population's elements are divided into distinct groups or strata where within each stratum the elements are similar to each other with respect to select characteristics of importance to the survey. Stratification is also used to increase the efficiency of a sample design with respect to survey costs and estimator precision. In this article, the foundations of stratified sampling are discussed in the framework of simple random sampling. Topics include the forming of the strata and optimal sample allocation among the strata. Practical implementation issues for stratified sampling are discussed and include systematic sampling, implicit stratification, and the construction of strata using modern software. The importance of using stratified sampling in practice is demonstrated by its usage in five major large‐scale health surveys conducted in the United States and the United Kingdom. For these surveys, details of the stratification and sampling methods are provided. Topics include multistage cluster sampling within strata and the use of systematic and probability proportional to size sampling.
Nearest Neighbor Methods: Overview with Examples
Authors: Dixon Philip M. 
Published: February 2017

AbstractThis article discusses nearest neighbor (NN) methods for the analysis of spatial point patterns and the analysis of field experiments. The distance from a point to its NN, or quantities derived from that distance, can be used to test whether the observed locations are a realization of a specific spatial point process. Edge effects, caused by recording data only within a bounded study area, can be important. When locations are marked (e.g., by the species of plant), NN methods provide information on the relationship between the marks. NN methods for field experiments can be used to model local spatial variability and improve estimates of treatment effects.
Women in Statistics
Authors: Golbeck Amanda L. , Ramírez Ramírez Lilia L. , Gel Yulia R. 
Published: February 2017

Abstract
Women's presence in the statistical sciences and other STEM disciplines made dramatic gains in the past few decades. However, there still exists the so‐called pyramid effect, that is, the number of women statisticians dramatically plummets as one climbs up the career ladder. One of the key constraints on this path is insufficient number of role models, that is, women statisticians and their successes tend to be “unseen.” We aim to bridge the gap on role models and provide a broad (nonexhaustive) overview on the impact of women in the history of statistical sciences.
Synthesis of 2‐Alkylaminoquinolines and 1,8‐Naphthyridines by Successive Ruthenium‐Catalyzed Dehydrogenative Annulation and N‐Alkylation Processes
Authors: Lv Wan , Xiong Biao , Jiang Huanfeng , Zhang Min 
Published: February 2017

AbstractA new one‐pot synthetic protocol, enabling the facile access to 2‐alkylaminoquinolines and 1,8‐naphthyridines by successive ruthenium‐catalyzed dehydrogenative annulation and N‐alkylation processes, has been demonstrated. A series of 2‐aminoarylmethanols were efficiently converted in combination with different types of nitriles and alcohols into various desired products in moderate to excellent yields after isolation. Advantageously, the synthesis proceeds with high atom‐efficiency, broad substrate scope, operational simplicity, no need for external hydrogen sources and less environmentally benign halogenated reagents, thus offering a practical approach to access these two types of compounds that are currently difficult to prepare with the conventional methods.magnified image
Global effects of income and income inequality on adult height and sexual dimorphism in height
Authors: Bogin Barry , Scheffler Christiane , Hermanussen Michael 
Published: February 2017

AbstractObjectivesAverage adult height of a population is considered a biomarker of the quality of the health environment and economic conditions. The causal relationships between height and income inequality are not well understood. We analyze data from 169 countries for national average heights of men and women and national‐level economic factors to test two hypotheses: (1) income inequality has a greater association with average adult height than does absolute income; and (2) neither income nor income inequality has an effect on sexual dimorphism in height.MethodsAverage height data come from the NCD‐RisC health risk factor collaboration. Economic indicators are derived from the World Bank data archive and include gross domestic product (GDP), Gross National Income per capita adjusted for personal purchasing power (GNI_PPP), and income equality assessed by the Gini coefficient calculated by the Wagstaff method.ResultsHypothesis 1 is supported. Greater income equality is most predictive of average height for both sexes. GNI_PPP explains a significant, but smaller, amount of the variation. National GDP has no association with height. Hypothesis 2 is rejected. With greater average adult height there is greater sexual dimorphism.ConclusionsFindings support a growing literature on the pernicious effects of inequality on growth in height and, by extension, on health. Gradients in height reflect gradients in social disadvantage. Inequality should be considered a pollutant that disempowers people from the resources needed for their own healthy growth and development and for the health and good growth of their children.
The Osteology Lesson of Sebastiaen Egbertszn (1619)
Authors: IJpma F F A , van Gulik T M 
Published: February 2017

Abstract
In 1619 the Amsterdam Guild of Surgeons commissioned a recognized Dutch painter to make a group portrait of the governors. This masterpiece is known as The Osteology Lesson of Sebastiaen Egbertszn. Egbertszn, praelector anatomiae (lecturer in anatomy), is depicted while demonstrating the human bones using the skeleton of an English pirate. The subject of this painting reminds us of the doctrine of osteology as part of the former surgical training. The lives and work of the represented governors of the guild and their teacher Sebastiaen Egbertszn, as well as details of the skeleton, are discussed after examination of the literature and original guild documents pertaining to the painting.

The Osteology Lesson of Sebastiaen Egbertszn (1619) is a group portrait of the governors of the Amsterdam Guild of Surgeons. It represents one of a series of nine anatomy lessons commissioned in the 17th and 18th centuries. Sebastiaen Egbertszn, who was the praelector anatomiae (lecturer in anatomy) at that time, is depicted demonstrating human bone anatomy using the skeleton of an executed pirate. Egbertszn died during a plague epidemic only 2 years after the painting was delivered and the identity of the artist remains contentious to this day. It is exhibited in the Amsterdam Museum in Amsterdam, The Netherlands.
Read more about the stories behind this masterpiece in an essay online.
An abscopal effect in a case of concomitant treatment of locally and peritoneally recurrent gastric cancer using adoptive T‐cell immunotherapy and radiotherapy
Authors: Sato Hiro , Suzuki Yoshiyuki , Yoshimoto Yuya , Noda Shin‐ei , Murata Kazutoshi , Takakusagi Yosuke , Okazaki Atsushi , Sekihara Tetsuo , Nakano Takashi 
Published: February 2017

Key Clinical MessageThe mechanism of abscopal effect is becoming clear by the progress of cancer immunology. A 54‐year‐old male with recurrent gastric cancer presented an abscopal effect after radiotherapy with concurrent adoptive T‐cell immunotherapy (immunoradiotherapy). Immunoradiotherapy has potential to induce abscopal effect by strengthening systemic antitumor immunity even in recurrent cancer.