bluuebunny/crossref_metadata_2025 huggingface dataset:
Swarm Observation of Field‐Aligned Currents Associated With Multiple Auroral Arc Systems
Authors: Wu J. , Knudsen D. J. , Gillies D. M. , Donovan E. F. , Burchill J. K.
Published: September 2017

Auroral arcs occur in regions of upward field‐aligned currents (FACs); however, the relation is not one to one, since kinetic energy of the current‐carrying electrons is also important in the production of auroral luminosity. Multiple auroral arc systems provide an opportunity to study the relation between FACs and auroral brightness in detail. In this study, we have identified two types of FAC configurations in multiple parallel arc systems using ground‐based optical data from the Time History of Events and Macroscale Interactions during Substorms all‐sky imagers, magnetometers and electric field instruments on board the Swarm satellites. In “unipolar FAC” events, each arc is an intensification within a broad, unipolar current sheet and downward return currents occur outside of this broad sheet. In “multipolar FAC” events, multiple arc systems represent a collection of multiple up/down current pairs. By collecting 17 events with unipolar FAC and 12 events with multipolar FACs, we find that (1) unipolar FAC events occur most frequently between 20 and 21 magnetic local time and multipolar FAC events tend to occur around local midnight and within 1 h after substorm onset. (2) Arcs in unipolar FAC systems have a typical width of 10–20 km and a spacing of 25–50 km. Arcs in multipolar FAC systems are wider and more separated. (3) Upward currents with more arcs embedded have larger intensities and widths. (4) Electric fields are strong and highly structured on the edges of multiple arc system with unipolar FAC. The fact that arcs with unipolar FAC are much more highly structured than the associated currents suggests that arc multiplicity is indicative not of a structured generator deep in the magnetosphere, but rather of the magnetosphere‐ionosphere coupling process.
Decadal Polar Motion of the Earth Excited by the Convective Outer Core From Geodynamo Simulations
Authors: Kuang W. , Chao B. F. , Chen J.
Published: September 2017

Long time geodetic observation records show that the orientation of the Earth's rotation axis with respect to the terrestrial reference frame, or polar motion, changes on a broad range of timescales. Apart from external torques from the luni‐solar tides, these changes are excited by interactions among different components of the Earth system. The convective fluid outer core has long been conjectured a likely contributor to the observed polar motion on timescales upward of decades, such as the ∼30 year Markowitz wobble. We investigated the electromagnetic coupling scenario across the core‐mantle boundary via numerical geodynamo simulation for different geodynamo parameters (Rayleigh numbers and magnetic Rossby numbers). Our simulated polar motion varies strongly with the dynamo parameters, while its excitation on decadal timescales appear to converge asymptotically within the adopted range of numerical Rossby numbers. Three strongest asymptotic modes emerge from numerical results, with periods around 30, 40, and 60 years for the prograde excitation and around 24, 30, and 60 years for the retrograde excitation. Their amplitudes are all larger than 5 × 10−8, or approximately 10 milliseconds of arc. The results suggest that the electromagnetic core‐mantle coupling could explain a substantial portion, if not all, of the observed decadal polar motion. In particular, the predicted 60 year polar motion deserves special attention for future observations and studies.
A Multialgorithm Approach to Land Surface Modeling of Suspended Sediment in the Colorado Front Range
Authors: Stewart J. R. , Livneh B. , Kasprzyk J. R. , Rajagopalan B. , Minear J. T. , Raseman W. J.
Published: September 2017

A new paradigm of simulating suspended sediment load (SSL) with a Land Surface Model (LSM) is presented here. Five erosion and SSL algorithms were applied within a common LSM framework to quantify uncertainties and evaluate predictability in two steep, forested catchments (>1,000 km2). The algorithms were chosen from among widely used sediment models, including empirically based: monovariate rating curve (MRC) and the Modified Universal Soil Loss Equation (MUSLE); stochastically based: the Load Estimator (LOADEST); conceptually based: the Hydrologic Simulation Program—Fortran (HSPF); and physically based: the Distributed Hydrology Soil Vegetation Model (DHSVM). The algorithms were driven by the hydrologic fluxes and meteorological inputs generated from the Variable Infiltration Capacity (VIC) LSM. A multiobjective calibration was applied to each algorithm and optimized parameter sets were validated over an excluded period, as well as in a transfer experiment to a nearby catchment to explore parameter robustness. Algorithm performance showed consistent decreases when parameter sets were applied to periods with greatly differing SSL variability relative to the calibration period. Of interest was a joint calibration of all sediment algorithm and streamflow parameters simultaneously, from which trade‐offs between streamflow performance and partitioning of runoff and base flow to optimize SSL timing were noted, decreasing the flexibility and robustness of the streamflow to adapt to different time periods. Parameter transferability to another catchment was most successful in more process‐oriented algorithms, the HSPF and the DHSVM. This first‐of‐its‐kind multialgorithm sediment scheme offers a unique capability to portray acute episodic loading while quantifying trade‐offs and uncertainties across a range of algorithm structures.
Calibration, Issues in
Authors: Bzik Thomas J.
Published: September 2017

Calibration establishes and standardizes common units of measurement for commerce and scientific study. Through calibration, the measured item or sample is related to items or samples with known properties, the standards. Statistical methods are typically used to identify and quantify the form of the relationship between sample measurements and one or more standards. They are also used to evaluate the accuracy and precision of the current and alternative measurement methods. Statistical tools are also used to determine the optimal frequency of recalibration and the frequency with which calibration should be checked. Calibration models can take the form of linear relationships or a nonlinear relationship. Two‐variable calibration models are often monotonic in their form. While many calibration models often involve only two variables, they can be multivariate in nature. Keeping bias out of calibration models requires not only selecting the correct model form but also ensuring that the model is fit, using an appropriate optimization criteria. Calibration models typically provide very high explanatory powers as compared to other typical scientific modeling applications such as plant or process optimization studies. Calibration models also typically yield extremely good levels of statistical significance. Current common statistical toolsets used in calibration studies are often not well structured for handling the actual, and sometimes complex, error structures that occur in routine application of calibration.
Leukemia Clusters
Authors: Bithell John F.
Published: September 2017

The nature of leukemia clusters is explored, and the evidence is reviewed. There are a small number of isolated clusters that may point to an environmental etiology, but the evidence is not clear‐cut. More widespread clustering appears to be a real, if rather weak, phenomenon. It could be attributable to environmental or genetic variation in risk, though it may also be indicative of an infective mechanism or a mechanism affecting the immunity of particular groups.
Binomial Confidence Interval
Authors: Agresti Alan , Lunneborg Clifford E.
Published: September 2017

The binomial parameter , the proportion of successes in a population, has as its maximum likelihood point estimator the proportion of successes, , observed in a random sample from that population. Standard confidence intervals (CIs) for are based on inverting results of corresponding significance tests about . For example, 95% CIs contain all null hypothesis values for for which the ‐value in the test exceeds 0.05. The methods include small‐sample “exact” CIs that are conservative (have actual confidence level bounded below by the nominal level) and large‐sample CIs based on the approximate normality of . A good small‐sample method is based on the binomial test using the mid‐‐value. A good large‐sample method is based on the score test. The simple CI that adds and subtracts from a ‐multiple of the estimated standard error is based on the Wald test and has poor performance. That method is adequate for all if one first adds two successes and two failures before implementing it.
Differential Item Functioning
Authors: Rogers H. Jane
Published: September 2017

Differential item functioning (DIF) occurs when individuals at the same level on the trait(s) or construct(s) being assessed but from different subpopulations have unequal probabilities of attaining a given score on the item. Methods for investigating DIF have been developed for both dichotomously and polytomously scored items. These methods may be classified by whether they condition on an unobserved or observed variable. Item response theory, logistic regression, Mantel–Haenszel (MH), and SIBTEST procedures for dichotomously scored responses and their extensions to polytomous responses are currently the most widely used methods for detecting DIF in practice. Current research interest focuses on sophisticated latent variable models that may facilitate a better understanding of the causes of DIF.
Structural Equation Modeling: An Overview
Authors: Schumacker Randall E.
Published: September 2017

Structural equation modeling (SEM) software programs test theoretical models using a sample variance–covariance matrix, although a correlation matrix with means and standard deviations for the observed variables can be input because these values can be used to create a variance–covariance matrix. A LISREL‐SIMPLIS program is given to illustrate how the sample data and theoretical model are specified in a SEM program.
Dispersion Parameter
Authors: Piegorsch Walter W.
Published: September 2017

To describe the stochastic nature of an outcome variable, data analysts use probability distributions. A crucial feature of many simple probability models is that structural relationships may be required between the population mean and other components of the model. Many experimental settings occur, however, where such a mean/variance structure is too restrictive: the data often exhibit variation larger than or, in some instances, smaller than that required under these simpler models. Such occurrences are collectively known asoverdispersionorunderdispersion, respectively. To quantify the extent of the over/underdispersion, a model parameter can be dedicated to it in the variance term. The resultingdispersion parameteris used to identify, study, test, or otherwise account for the excess variation. This article reviews statistical aspects of and estimation for such dispersion parameters.
Superamphiphobic Coatings from Combination of a Biomimetic Catechol‐Bearing Fluoropolymer and Halloysite Nanotubes
Authors: Ma Wei , Higaki Yuji , Takahara Atsushi
Published: September 2017

Superamphiphobic coatings with remarkable water and oil repellency are prepared by the combination of a biomimetic catechol‐bearing fluoropolymer, poly{2‐(perfluorooctyl)ethyl acrylate‐co‐N‐(3,4‐dihydroxyphenethyl) acrylamide} (P(FAC8‐co‐DOPAm)), and naturally available halloysite nanotubes (HNTs). They are based on surface modification of HNTs with P(FAC8‐co‐DOPAm). A procedure to attain stable affinity between silica and the copolymer is established, and used for surface modification of HNTs. Superamphiphobic coatings are obtained by casting the suspension of P(FAC8‐co‐DOPAm)‐modified HNTs onto substrates. The superamphiphobic coatings exhibit Cassie–Baxter's wetting to liquids with a wide range of surface tension, because of the extremely low surface free energy and the unique micro‐/nanohierarchical surface topography, as well as the re‐entrant curvature of HNTs. These superamphiphobic coatings are environmentally and chemically durable, and can resist water scouring. The abundance of HNTs in nature and the easily controlled process of this method ensure an efficient approach for large‐scale production of superamphiphobic coatings for various applications.
Optimization of Photon and Electron Collection Efficiencies in Silicon Solar Microcells for Use in Concentration‐Based Photovoltaic Systems
Authors: Yoder Mikayla A. , Yao Yuan , He Junwen , Nuzzo Ralph G.
Published: September 2017

Ultrathin silicon solar microcells (μ‐cells) afford a means to reduce semiconductor material consumption and can be integrated with concentration optics to improve their power density. A μ‐cell design is described that optimizes electron and photon collection with enhanced efficiency for solar concentration applications. An interdigitated back contact (IBC) design improves carrier collection partially due to larger contact coverage while further enabling optimization of the μ‐cell front surface. To do so, a silicon nitride antireflection thin film coating is utilized to enhance photon absorption and improve surface passivation. Performance of IBC μ‐cells is compared to an optimized top contact design and improves μ‐cell conversion efficiencies from 9.9 to 13.7%. Improvements at 1 Sun are amplified under concentration and increase power densities at 20 Suns to 346 from 192 mW cm−2 due to minimized series resistance. Benefits afforded by IBC μ‐cells are exemplified following their integration into a dual concentrator system, affording photon collection capacities for direct and diffuse irradiance. A traditional lens concentrates direct light while a luminescent solar concentrator (LSC) collects diffuse photons otherwise not utilized by passive optics. Addition of the LSC increases maximum power densities on clear and cloudy days, providing concentration for the latter and further increasing the power density.
Numerical prediction of dust capture efficiency of a centrifugal wet scrubber
Authors: Ali Hassan , Plaza Floren , Mann Anthony
Published: September 2017

The gas, liquid, and dust particle behavior inside a centrifugal wet scrubber was simulated and a submodel for predicting its collection efficiency was developed that also takes in account the reduction in collection efficiency due to droplet carryover. Centrifugal wet scrubbers are used in many industries and deliver a high scrubbing efficiency at relatively low capital and operational costs. However, they often experience problems such as droplet carryover at high gas flows and reduced collection efficiency at low gas flows. An improved understanding of flow processes inside the scrubbers is needed to develop a better scrubber design. An experimental test facility was setup for this purpose which also served to validate the CFD modeling results. Ideal operating parameters for maximum scrubbing efficiency and minimum droplet carryover were identified. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1001–1012, 2018
2‐hydroxyethylammonium formate ionic liquid grafted magnetic nanoparticle as a novel heterogeneous catalyst for the synthesis of substituted imidazoles
Authors: Rajabzadeh Maryam , Eshghi Hossein , Khalifeh Reza , Bakavoli Mehdi
Published: September 2017

Catalytic one‐pot condensation of benzil, aldehyde and ammonium acetate have been successfully carried out using 2‐hydroxyethylammonium formate (HEAF) grafted on a magnetic nanoparticles as a new heterogeneous catalyst. The as‐prepared catalyst was characterized by FT‐IR, TEM, FESEM, VSM, TGA and XRD. This catalyst indicated significant advantages, such as excellent yields, shorter reaction time, reusability of the catalyst and easy workup process.
Silver nanoparticles immobilized onto poly(4‐vinylpyridine)‐functionalized magnetic nanoparticles: A robust magnetically recyclable catalyst for oxidant‐free alcohol dehydrogenation
Authors: Bayat Ahmad , Shakourian‐Fard Mehdi , Talebloo Nazanin , Hashemi Mohammed Mahmoodi
Published: September 2017

A heterogeneous and recyclable catalyst with a high loading of silver nanoparticles was synthesized via the silver nanoparticles being supported onto the surface of magnetic nanoparticles coated with poly(4‐vinylpyridine). The synthesized catalyst was used in the dehydrogenation of alcohols to corresponding carbonyl compounds. A broad diversity of alcohols was converted into their corresponding carbonyl compounds in excellent yields. The catalyst was easily recovered by applying an external magnetic field and reused for seven reaction cycles without considerable loss of activity. The catalyst was fully characterized using various techniques.
Macro‐level diffusion of a methodological knowledge innovation: Research synthesis methods, 1972–2011
Authors: Sheble Laura
Published: September 2017

Use of research synthesis methods has contributed to changes in research practices. In disciplinary literatures, authors indicate motivations to use the methods include needs to (a) translate research‐based knowledge to inform practice and policy decisions, and (b) integrate relatively large and diverse knowledge bases to increase the generality of results and yield novel insights or explanations. This review presents two histories of the diffusion of research synthesis methods: a narrative history based primarily in the health and social sciences; and a bibliometric overview across science broadly. Engagement with research synthesis was strongly correlated with evidence‐based practice (EBP), and moderately with review prevalence. The social sciences were most diverse in terms of when research synthesis was adopted. Technology, physical sciences, and math appear to be relatively resistant though fields such as physics may be considered to have used similar methods long ago. Additional research is needed to assess the consequences of adoption within fields, including changes in how researchers engage with knowledge resources. This review demonstrates that particularistic histories of science and technology may be fruitfully augmented with informetrics to examine how disciplinary diffusion narratives coincide with patterns across science more broadly, thereby opening up disciplinary knowledge to inform future research.
An I&I‐Based Observer to Solve the Output‐Feedback Synchronization Problem for a Class of Chaotic Systems
Authors: Aguilar‐Ibañez Carlos , García‐Canseco Eloísa , Martínez‐García Rafael , Martínez‐García Juan Carlos , Suarez‐Castañon Miguel Santiago
Published: September 2017

A novel robust observer, intended to solve the output‐feedback chaos synchronization problem for the Master/Slave Configuration, is proposed here. Assuming that the given Master system belongs to a specific class of feedback‐linearized systems, our solution is based on the well‐known Immersion and Invariance (I&I) method. The proposed observer is devoted to the asymptotic estimation of the Master system's underlying dynamics, and its effectiveness is illustrated via computer‐based simulations that involve both the so‐called Duffing's oscillator and the Genesio & Tesi system.
Novel Mutation of LRP6 Identified in Chinese Han Population Links Canonical WNT Signaling to Neural Tube Defects
Authors: Shi Zhiwen , Yang Xueyan , Li Bin‐Bin , Chen Shuxia , Yang Luming , Cheng Liangping , Zhang Ting , Wang Hongyan , Zheng Yufang
Published: September 2017

Background

Neural tube defects (NTDs), the second most frequent cause of human congenital abnormalities, are debilitating birth defects due to failure of neural tube closure. It has been shown that noncanonical WNT/planar cell polarity (PCP) signaling is required for convergent extension (CE), the initiation step of neural tube closure (NTC). But the effect of canonical WNT//β‐catenin signaling during NTC is still elusive. LRP6 (low density lipoprotein receptor related proteins 6) was identified as a co‐receptor for WNT/β‐catenin signaling, but recent studies showed that it also can mediate WNT/PCP signaling.

Methods

In this study, we screened mutations in the LRP6 gene in 343 NTDs and 215 ethnically matched normal controls of Chinese Han population.

Results

Three rare missense mutations (c.1514A>G, p.Y505C); c.2984A>G, p.D995G; and c.4280C>A, p.P1427Q) of the LRP6 gene were identified in Chinese NTD patients. The Y505C mutation is a loss‐of‐function mutation on both WNT/β‐catenin and PCP signaling. The D995G mutation only partially lost inhibition on PCP signaling without affecting WNT/β‐catenin signaling. The P1427Q mutation dramatically increased WNT/β‐catenin signaling but only mildly loss of inhibition on PCP signaling. All three mutations failed to rescue CE defects caused by lrp6 morpholino oligos knockdown in zebrafish. Of interest, when overexpressed, D995G did not induce any defects, but Y505C and P1427Q caused more severe CE defects in zebrafish.

Conclusion

Our results suggested that over‐active canonical WNT signaling induced by gain‐of‐function mutation in LRP6 could also contribute to human NTDs, and a balanced WNT/β‐catenin and PCP signaling is probably required for proper neural tube development. Birth Defects Research 110:63–71, 2018. © 2017 Wiley Periodicals, Inc.
A Brake for B Cell Proliferation
Authors: Jellusova Julia , Rickert Robert C.
Published: September 2017

B cell activation is accompanied by metabolic adaptations to meet the increased energetic demands of proliferation. The metabolic composition of the microenvironment is known to change during a germinal center response, in inflamed tissue and to vary significantly between different organs. To sustain cellular homeostasis B cells need to be able to dynamically adapt to changes in their environment. An inability to take up and process available nutrients can result in impaired B cell growth and a diminished humoral immune response. Furthermore, the metabolic microenvironment can affect B cell signaling and provide a means to avoid aberrant proliferation or modulate B cell function. Thus, a better understanding of the intricate interplay between cell signaling and metabolism could provide novel insight into how B cell function is regulated and have implications for the development of vaccines or treatment of autoimmune disorders and B cell derived malignancies.
Keep your eye on…
Authors: Knopf Alison
Published: September 2017

The benefits of screening for postpartum depression during well‐child visits

The adverse effects on telomere length of father loss, especially in death or incarceration

The lack of evidence — pro or con — for opioids for chronic noncancer pain in children and adolescents
Back Cover: Asymmetric Synthesis of Chiral α‐Substituted Mercaptoglycine Derivatives via α‐Sulfenylation of Ni(II) Complex of Glycine and S‐Substituted 4‐Methylbenzenesulfonothioate (Chin. J. Chem. 9/2017)
Authors: Li Jia , Song Xiaohan , Zhou Shengbin , Wang Jiang , Liu Hong
Published: September 2017

The back cover picture shows the asymmetric synthesis of α‐substituted mercaptoglycine via nickel(II) complex. The α‐substituted mercaptoglycine is an important framework of various peptide drugs and nickel(II) complex can be utilized to generate single enantiomer of α‐substituted amino acid efficiently. This work establishes an efficient method to access α‐substituted mercaptoglycine with good yield and high stereoselectivity, which can promote the design of new peptide drugs in a broad scope. More details are discussed in the article by Wang et al. on page 1383‐1390.

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Identification of Atuveciclib (BAY 1143572), the First Highly Selective, Clinical PTEFb/CDK9 Inhibitor for the Treatment of Cancer
Authors: Lücking Ulrich , Scholz Arne , Lienau Philip , Siemeister Gerhard , Kosemund Dirk , Bohlmann Rolf , Briem Hans , Terebesi Ildiko , Meyer Kirstin , Prelle Katja , Denner Karsten , Bömer Ulf , Schäfer Martina , Eis Knut , Valencia Ray , Ince Stuart , von Nussbaum Franz , Mumberg Dominik , Ziegelbauer Karl , Klebl Bert , Choidas Axel , Nussbaumer Peter , Baumann Matthias , Schultz‐Fademrecht Carsten , Rühter Gerd , Eickhoff Jan , Brands Michael
Published: September 2017

Selective inhibition of exclusively transcription‐regulating PTEFb/CDK9 is a promising new approach in cancer therapy. Starting from lead compound BAY‐958, lead optimization efforts strictly focusing on kinase selectivity, physicochemical and DMPK properties finally led to the identification of the orally available clinical candidate atuveciclib (BAY 1143572). Structurally characterized by an unusual benzyl sulfoximine group, BAY 1143572 exhibited the best overall profile in vitro and in vivo, including high efficacy and good tolerability in xenograft models in mice and rats. BAY 1143572 is the first potent and highly selective PTEFb/CDK9 inhibitor to enter clinical trials for the treatment of cancer.
Support the success of a new provost
Authors: Crabtree Robbin D. , Sapp David Alan
Published: September 2017

Soon after being appointed dean for the first time, Robbin remembers reading an article for new administrators. The advice that struck her — and proved to be both insightful and helpful — was something like “Beware the first shark to swim up to the boat.”
Enhanced ethanol production from sugarcane bagasse hydrolysate with high content of inhibitors by an adapted barnettozyma californica
Authors: Nouri Hoda , Azin Mehrdad , Mousavi S. Latif
Published: September 2017

Bioethanol production from acid hydrolysate of sugarcane bagasse's hemicellulose was studied using an adapted new yeast strain, Barnettozyma californica HNMA‐5. The growth rate and ethanol production were studied by using the adapted and the parental strains in Sugarcane Bagasse Hydrolysate (SBH) and Concentrated Sugarcane Bagasse Hydrolysate (CSBH). The hydrolysate concentration resulted in an increase of total sugar from 34 to 51.8 g L−1 and an approximately twofold increase in nonvolatile toxic compounds like phenol (1.017–2.11 g L−1) in CSBH. An adaptation of the yeast strain to CSBH resulted in improved growth ability and ethanol production, whereas no significant effect was observed in SBH. The adapted yeast showed a promising ethanol production of 4.804 g L−1 after 24 h compared to the parental strain, which produced 1.233 g L−1 after 72 h of fermentation. The adapted yeast could produce about four times more ethanol than the parental strain. In addition, the lag phase decreased from 9 to 5 h and productivity increased 10‐fold. Furthermore, the hydrolysate concentration and the yeast's adaptation were effective methods to improve ethanol production in CSBH. Our data indicate that the new yeast isolate, B. californica HNMA‐5 could be successfully applied to lignocellulosic ethanol production. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1169–1175, 2018
Variability of Liver Shear Wave Measurements Using a New Ultrasound Elastographic Technique
Authors: Nadebaum David P. , Nicoll Amanda J. , Sood Siddharth , Gorelik Alexandra , Gibson Robert N.
Published: September 2017

Objectives

A new 2‐dimensional (2D) shear wave elastographic (SWE) device has been developed for the noninvasive assessment of liver fibrosis. Guidelines on measurement acquisition parameters are not yet well established for this technique. Our study aimed to assess 2D SWE measurement variability and to determine the number of measurements required per patient to reliably assess liver stiffness.

Methods

Two‐dimensional SWE was assessed in 55 patients with mixed‐etiology chronic liver disease on an Aplio 500 ultrasound system (Toshiba Medical Systems Corporation, Tochigi, Japan). Ten measurements were obtained per patient by an operator blinded to all preceding readings. Results were analyzed with clinical information obtained from medical records.

Results

The median interquartile range/median ratio for 2D SWE was 0.131 (quartiles 1–3, 0.089–0.174). Five readings provided an approximation within 0.11 m/s, or 4.2% of the median velocity of 10 measurements. Factors associated with increased measurement variability included body mass index (ρ = 0.388; P = .01), increased skin‐to‐liver capsule distance (ρ = 0.426; P = .002), and measurements taken within 1.5 cm of the liver capsule (P < .001). Measurements with heterogeneous shear wave profiles (indicated by a region of interest [ROI] SD/speed ratio > 0.15) showed greater deviation from the set's median velocity than those with an ROI SD/speed ratio of 0.15 or lower (0.42 versus 0.22 m/s; P = .001).

Conclusions

Two‐dimensional SWE showed low overall measurement variability, with a minimum of 5 readings providing equivalent precision to the existing method using 10 samples. Obesity, increasing abdominal wall thickness, subcapsular measurements and an ROI SD/speed ratio of greater than 0.15 were all associated with increased measurement variability. The ROI SD/speed ratio warrants further evaluation as a quality assessment metric, to allow objective operator assessment of individual 2D SWE measurement reliability in real time.
Fertility Treatment Outcomes After Follicle Tracking With Standard 2‐Dimensional Sonography Versus 3‐Dimensional Sonography‐Based Automated Volume Count: Prospective Study
Authors: Wertheimer Avital , Nagar Ran , Oron Galia , Meizner Israel , Fisch Benjamin , Ben‐Haroush Avi
Published: September 2017

Objectives

The use of sonography‐based Automated Volume Count (SonoAVC; GE Healthcare, Kretz, Zipf, Austria) leads to substantially lower intraobserver and interobserver variability with a considerable advantage in time gain for both the physician and patient. It offers the possibility of continuous training and standardization of follicular monitoring. Manual and automated follicular measurements during in vitro fertilization (IVF) are reported to be comparable during gonadotropin‐releasing hormone (GnRH) agonist treatment. The aim of our study was to evaluate the effect of follicle tracking with 3‐dimensional (3D) SonoAVC on treatment outcomes in GnRH antagonist IVF cycles.

Methods

A prospective trial included 54 women undergoing their first to fourth GnRH antagonist IVF cycles. Follicle tracking from the initiation of ovarian stimulation until the day of oocyte retrieval and timing of oocyte retrieval was done either by conventional 2‐dimensional (2D) sonography or 3D SonoAVC (open‐labeled parallel assignment). In both groups, recombinant human chorionic gonadotropin was injected when there were at least 3 leading follicles measuring 17 mm. The primary outcome was the oocyte maturation rate, and secondary outcomes were the fertilization rate and clinical pregnancy rate.

Results

The number of retrieved oocytes, number and rate of mature oocytes, fertilization rate, and clinical pregnancy rate were similar for 2D sonography and 3D SonoAVC. On a multivariate regression analysis, the use of 3D sonography was not a significant independent predictor of mature oocytes or clinical pregnancy rates.

Conclusions

Follicle tracking with 3D sonographic follicular volume measurements does not achieve better fertility outcomes than standard 2D sonography.
Combined Influence of Gestational Weight Gain and Estimated Fetal Weight on Risk Assessment for Small‐ or Large‐for‐Gestational‐Age Birth Weight: A Prospective Cohort Study
Authors: Pugh Sarah J. , Hinkle Stefanie N. , Kim Sungduk , Albert Paul S. , Newman Roger , Grobman William A. , Wing Deborah A. , Grantz Katherine L.
Published: September 2017

Objectives

To evaluate the frequency with which gestational weight gain and estimated fetal weight do not track across gestation and to assess the risk of small‐for‐gestational‐age (SGA) and large‐for‐gestational‐age (LGA) birth weight as a function of tracking.

Methods

This study included a pregnancy cohort (2009–2013) of 2438 women from 4 racial/ethnic groups in the United States. We calculated race‐ and trimester‐specific gestational weight gain and estimated fetal weight z scores. The prevalence of how often gestational weight gain and estimated fetal weight did not or did directly track was examined by grouping z scores into measure‐specific categories (<−1 SD, −1 to + 1 SD, and >1 SD) and then examining 2‐measure combinations. Trimester‐specific relative risks for SGA and LGA births were estimated with a gestational weight gain and estimated fetal weight z score interaction. We estimated coefficients for selected gestational weight gain and estimated fetal weight values (–1 SD, 0 SD, and +1 SD) compared with the referent of 0 SD for both measures. Small and large for gestational age were calculated as birth weight below the 10th and at or above the 90th percentiles, respectively.

Results

Gestational weight gain and estimated fetal weight were within 1 SD 55.5%, 51.5%, and 48.2% of the time in the first, second, and third trimesters, respectively. There was no significant interaction between gestational weight gain and estimated fetal weight on the risk of SGA in the first and second trimesters (interaction term P = .48; P = .79). In the third trimester, there was a significant interaction (P = .002), resulting in a 71% (95% confidence interval, 1.45–2.02) increased risk of SGA when estimated fetal weight was low and gestational weight gain was high. These relationships were similar for the risk of LGA.

Conclusions

Deviations in either measure, even in the presence of average gestational weight gain or estimated fetal weight, still suggest an increased risk of SGA and LGA.
Ultrasonographic Evaluation of Zone II Partial Flexor Tendon Lacerations of the Fingers: A Cadaveric Study
Authors: Kazmers Nikolas H. , Gordon Joshua A. , Buterbaugh Kristen L. , Bozentka David J. , Steinberg David R. , Khoury Viviane
Published: September 2017

Objectives

Accurate assessment of zone II partial flexor tendon lacerations in the finger is clinically important. Surgical repair is recommended for lacerations of greater than 50% to 60%. Our goal was to evaluate ultrasonographic test characteristics and accuracy in identifying partial flexor tendon lacerations in a cadaveric model.

Methods

From fresh‐frozen above‐elbow human cadaveric specimens, 32 flexor digitorum profundus tendons were randomly selected to remain intact or receive low‐ or high‐grade lacerations involving 10% to 40% and 60% to 90% of the radioulnar width within Verdan Zone II, respectively. Static and dynamic ultrasonography using a linear array 14‐MHz transducer was performed by a blinded musculoskeletal radiologist. Sensitivities, specificities, and other standard test performance metrics were calculated. Actual and measured percentages of tendon laceration were compared by the paired t test.

Results

After randomization, 24 tendons were lacerated (12 low‐ and 12 high‐grade), whereas 8 remained intact. The sensitivity and specificity in detecting the presence versus absence of a partial laceration were 0.54 and 0.75, respectively, with positive and negative likelihood ratio values of 2.17 and 0.61. For low‐grade lacerations, the sensitivity and specificity were 0.25 and 0.85, compared to 0.83 and 0.85 for high‐grade lacerations. Ultrasonography underestimated the percentage of tendon involvement by a mean of 18.1% for the study population as a whole (95% confidence interval, 9.0% to 27.2%; P < .001) but accurately determined the extent for correctly diagnosed high‐grade lacerations (–6.7%; 95% confidence interval, –18.7% to 5.2%; P = .22).

Conclusions

Ultrasonography was useful in identifying and characterizing clinically relevant high‐grade zone II partial flexor digitorum profundus lacerations in a cadaveric model.
Exploring novel poly(thiophene‐3‐yl‐amine) through facile self acid assisted‐polycondensation
Authors: Jiang Kang , Cheng Xi , Cai Xinyi , Yanagida Shozo , Xia Jiangbin
Published: September 2017

Aromatic moieties of benzene and pyridine as side chains for poly(thiophene‐3‐yl‐amine) are rationally designed and synthesized by facile self acid‐assisted polycondensation (SAAP). Nitrogen atom is the key atom to form ammonium cation which guarantees SAAP success while other aromatic moieties are chosen carefully to attach on N atom to functionalize poly(thiophene‐3‐yl‐amine) matrix. Our results indicate that thiophene‐3‐yl‐amine is an excellent platform to construct plenty of functionalized monomers candidates for SAAP. Our study would push SAAP or AAP scope forward and pave the way to explore much more polythiophene derivatives. Furthermore, DFT calculation is carried out to deep understand AAP mechanism. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 4003–4012
Rare case of subependymal giant cell astrocytoma without clinical features of tuberous sclerosis: Case report and literature review
Authors: Azam Mohammad , Rath Satyajeet , Khurana Rohini , Shukla Saumya , Parween Ruhi
Published: September 2017

Subependymal giant cell astrocytoma (SEGA) is a slow‐growing tumor originating in the walls of the lateral ventricles, usually presenting in the first two decades of life, and is often associated with tuberous sclerosis complex. However, few cases of SEGA without any clinical features of tuberous sclerosis complex have been reported. Here, we present a case of an 11‐year‐old boy with right hemibody weakness and headache for 1.5 years. He was diagnosed with solitary SEGA without any clinical features of tuberous sclerosis complex. Magnetic resonance imaging of the brain showed an intracranial space‐occupying lesion in the left internal capsule. Biopsy was consistent with SEGA. There were no stigmata of tuberous sclerosis complex. The patient was treated with curative intent by radiotherapy.
The Influence of Deposition Rates on Properties of AlPcCl Thin Films and on the Performance of Planar Organic Solar Cells
Authors: Mohammed‐Krarroubik A. , Morsli M. , Khelil A. , Cattin L. , Barkat L. , Tuo S. , El Jouad Z. , Louarn G. , Ghamnia M. , Addou M. , Bernède J. C.
Published: September 2017

The performance of organic photovoltaic cells depends on different properties of the organic materials, such as carrier mobility, band structure, morphology, and crystallinity. For AlPcCl, it is shown that these properties are dependent on the layer deposition rates. As the deposition rate increases, the surface roughness of AlPcCl layers decreases. In contrast, the crystallinity of the layers increases as the deposition rate decreases, thereby increasing the hole mobility value. These effects are opposed: the former effect allows higher open circuit voltages to be obtained as the deposition rate increases, whereas the latter increases the short circuit current as the deposition rate decreases. Therefore, there is a trade‐off between open and short circuit current values, and it is necessary to find the best deposition rate for AlPcCl. Here, it is shown that the highest mobility carriers in layers deposited slowly allow the use of thicker AlPcCl layers, which permits acceptable open circuit voltage values and optimum photovoltaic cell efficiencies to be obtained. This results in an optimum efficiency value of 3.97% for a 26‐nm‐thick AlPcCl film that is deposited at 0.02–0.03 nm s−1.
Application of the Partitioning Technique to Scattering Problems in the Theory of Non‐Relativistic Fermion‐Boson Quantum Fields
Authors: RÉDEI L. B.
Published: September 2017

The partitioning technique is used to calculate the approximate scattering amplitude for elastic fermion‐boson scattering in nonrelativistic quantum field theory. The approximation is not based on a power series expansion in the coupling constant and it is therefore applicable even in the case of strong coupling. For the applicability of the proposed approximation scheme it is required that the coupling should be linear in the boson field and that virtual fermion‐antifermion pair creation processes can be neglected. As an example low energy pion‐nucleon scattering is discussed in detail.

On emploie la méthode de partition pour calculer l'amplitude de diffusion approximative de la diffusion élastique fermion‐boson dans la théorie quantique des champs non‐relativiste. Cette approximation n'est pas basée sur un développement en puissances de la constante de couplage. Pour cette raison elle reste valable même dans le cas de couplage fort. Il est nécessaire, pourque la méthode d'approximation proposée soit applicable, que le couplage soit linéaire dans le champ des bosons et qu'on puisse négliger des procès de création de paires virtuelles fermion‐antifermion. On discute en detail la diffusion pion‐nucléon de basse énergie.

Die Partitionsmethode wurde zur Berechnung der approximativen Streuungsamplitude für elastische Fermion‐Bosonstreuung in nichtrelativistischer Quantenfeldtheorie angewendet. Diese Approximation beruht nicht auf einer Potenzreihenentwicklung in der Kopplungskonstante und ist dafür auch in dem Fall starker Kopplung anwendbar. Für die Anwendbarkeit der vorgeschlagenen Approximationsmethode ist es aber notwendig dass die Kopplung linear im Bosonfeld ist und dass Paarschöpfungsprozesse von virtuellen Fermion‐Antifermionen vernachlässigt werden können. Als Beispiel wurde die Pion‐Nukleonstreuung für tiefe Energien eingehend diskutiert.
On the Choice of Spin Functions in the AMO Method
Authors: LINDNER PETER , LUNELL STEN
Published: September 2017

The alternant‐molecular‐orbital (AMO) method as applied to the benzene molecule is reconsidered. A variational treatment was performed to determine the singlet spin function which gives the best total energy in the five‐dimensional spin space available. It is found that an AMO function containing two mixing parameters and an optimized spin function gives an energy improvement over the ordinary one‐parameter AMO method, utilizing a single spin function, by 0.452 eV. Optimization of the spin function alone gives an energy lowering which is 57% of this value, while a two‐parameter function with the usual spin function gives 86%.

On a reconsidéré l'application de la méthode des orbitales moléculaires alternantes (AMO) à la molécule de benzène. Par un calcul variationnel on a déterminé celle des fonctions singulettes de l'espace de spin à cinq dimensions, qui donne la meilleure énergie totale. On trouve qu'une fonction AMO à deux paramètres combinée à une fonction de spin optimisée donne une amélioration de l'énergie de 0.452 eV, sur la méthode AMO ordinaire à un seul paramètre et une seule fonction de spin. Une optimisation de la fonction de spin seulement donne 57% de cette valeur‐ci, tandis qu'une fonction à deux paramètres avec la fonction de spin ordinaire donne 86%.

Die alternierende Molekülorbitalmethode (AMO) wurde noch einmal auf das Benzolmolekül angewendet. Mit einer Variationsberechnung wird die Singulett‐Spinfunktion des fünfdimensionalen Spinraum bestimmt, die die beste Gesamtenergie liefert. Man findet das eine AMO‐funktion mit zwei Parametern und einer optimisierten Spinfunktion eine Energieverbesserung über die gewöhnliche AMO‐Methode mit einem Parameter und einer einzigen Spinfunktion, von 0.452 eV gibt. Optimisierung der Spinfunktion allein gibt 57% dieses Wert, während eine Zweiparameterfunktion mit der gewöhnlichen Spinfunktion 86% gibt.
Physical layer aware adaptive network coding schemes for satellite communications
Authors: Ghanem Samah A. M. , Gharsellaoui Ala Eddine , Tarchi Daniele , Vanelli Coralli Alessandro
Published: September 2017

Network coding is a technology that provides core benefits to communication services, in terms of reliability, latency, and data rate, by leveraging on a coding structure that reduces the necessity for retransmissions of packets. Satellite communications are one of the potential applications that can leverage on the benefits of network coding due to their challenging fading environments and high round trip times. By introducing physical layer awareness, network coding offers further gains to such communications systems. In this paper, we propose different rate and energy efficient adaptive network coding schemes for time‐variant channels. We compare our proposed physical layer aware adaptive schemes to physical layer nonadaptive network coding schemes for time‐variant channels. The proposed schemes demonstrate that adaptation of packet transmissions based on the channel variations over time, and their corresponding time‐dependent erasures, allows for significant gains in terms of throughput, delay, and energy efficiency. We shed light on the trade‐off between energy efficiency and delay‐throughput gains, demonstrating that conservative adaptive approaches that favor less transmission under high erasures might cause higher delay and less‐throughput gains in comparison to nonconservative approaches that favor more transmissions to account for high erasures. We show that such schemes are robust with regimes of large or small packet sizes; albeit the energy per bit is affected, similar rate and energy gains can be obtained. In turn, we show that the performance gains are driven by the duty cycle of the packets silent transmission and not by the packet size.
Reliability analysis of wind turbines under non‐Gaussian wind load
Authors: Shuang Miao , Song Bo
Published: September 2017

Based on translation models, both Gaussian and non‐Gaussian wind fields are generated using the harmony superposition method for examining the reliability of a typical wind turbine at operational and parked conditions. Using the blade aerodynamic model and multibody dynamics, wind turbine responses are calculated and then probability characteristics are analyzed in details. The short‐term extreme response distribution is estimated by the average conditional exceedance rate method at each mean wind speed bin, and the long‐term extreme response distribution is then determined by further integrating the short‐term extreme response distribution conditional on wind speed with the distribution of mean wind speed. Additionally, crack initiation life and crack propagation life are evaluated using the linear cumulative damage theory and linear crack propagation theory, respectively. The results indicate that non‐Gaussian characteristics of wind inflows have a noticeably greater influence on both extreme response and fatigue damage, and the Gaussian assumption cannot suit wind turbine in complex terrain.
Structural Complexity and Thermoelectric Properties of Quaternary and Quinary Tellurides (GexSn1–x)0.8(InySb1–y)0.13Te with 0 ≤ x,y ≤ 1
Authors: Neudert Lukas , Schwarzmüller Stefan , Scheel Manuel , Welzmiller Simon , Oeckler Oliver
Published: September 2017

Starting from stoichiometric mixtures of the elements, quaternary and quinary solid solutions (GexSn1–x)0.8(InySb1–y)0.13Te were obtained. Concerning the ratio Ge/Sn and Sb/In, respectively, lattice parameters of the metastable phases with rocksalt‐type average structures approximately obey Vegard's law. Stable phases correspond to a disordered rocksalt type at high temperature and to trigonal layered structures with van der Waal gaps at lower temperature as shown by temperature‐dependent powder X‐ray diffraction combined with TEM, which reveals layer‐like vacancy ordering, whose extent depends on composition and thermal treatment. In the long‐periodically ordered model compounds 21R‐Ge0.5Sn0.5InSbTe4 and 9P‐GeSnInSbTe5 studied by resonant scattering data at K‐absorption edges, Sb and Sn concentrate near the van der Waals gaps. Compared to Ge0.8Sb0.13Te and Sn0.8Sb0.13Te, the simultaneous presence of In and Sn combines increased electrical conductivity with low thermal conductivity and enhanced thermoelectric properties in certain temperature ranges. Phase transitions correlate with changes of the thermoelectric properties.