bluuebunny/crossref_metadata_2025 huggingface dataset:
Circulation, hydrography, and transport over the summit of Axial Seamount, a deep volcano in the Northeast Pacific
Authors: Xu G. , Lavelle J. W.
Published: May 2017

A numerical model of ocean flow, hydrography, and transport is used to extrapolate observations of currents and hydrography and infer patterns of material flux in the deep ocean around Axial Seamount, a destination node of NSF's Ocean Observatories Initiative's Cabled Array. Using an inverse method, the model is made to approximate measured deep ocean flow around this site during a 35 day time period in the year 2002. The model is then used to extract month‐long mean patterns and examine smaller‐scale spatial and temporal variability around Axial. Like prior observations, model month‐long mean currents flow anticyclonically around the seamount's summit in toroidal form with maximum speeds at 1500 m depth of 10–11 cm/s. As a time mean, the temperature (salinity) anomaly distribution takes the form of a cold (briny) dome above the summit. Passive tracer material continually released at the location of the ASHES vent field exits the caldera primarily through its southern open end before filling the caldera. Once outside the caldera, the tracer circles the summit in clockwise fashion, fractionally reentering the caldera over lower walls at its north end, while gradually bleeding southwestward during the modeled time period into the ambient ocean. A second tracer release experiment using a source of only 2 day duration inside and near the CASM vent field at the northern end of the caldera suggests a residence time of the fluid at that locale of 8–9 days.
The impact of stochastic physics on tropical rainfall variability in global climate models on daily to weekly time scales
Authors: Watson Peter A. G. , Berner Judith , Corti Susanna , Davini Paolo , von Hardenberg Jost , Sanchez Claudio , Weisheimer Antje , Palmer Tim N.
Published: May 2017

Many global atmospheric models have too little precipitation variability in the tropics on daily to weekly time scales and also a poor representation of tropical precipitation extremes associated with intense convection. Stochastic parameterizations have the potential to mitigate this problem by representing unpredictable subgrid variability that is left out of deterministic models. We evaluate the impact on the statistics of tropical rainfall of two stochastic schemes: the stochastically perturbed parameterization tendency scheme (SPPT) and stochastic kinetic energy backscatter scheme (SKEBS), in three climate models: EC‐Earth, the Met Office Unified Model, and the Community Atmosphere Model, version 4. The schemes generally improve the statistics of simulated tropical rainfall variability, particularly by increasing the frequency of heavy rainfall events, reducing its persistence and increasing the high‐frequency component of its variability. There is a large range in the size of the impact between models, with EC‐Earth showing the largest improvements. The improvements are greater than those obtained by increasing horizontal resolution to ∼20 km. Stochastic physics also strongly affects projections of future changes in the frequency of extreme tropical rainfall in EC‐Earth. This indicates that small‐scale variability that is unresolved and unpredictable in these models has an important role in determining tropical climate variability statistics. Using these schemes, and improved schemes currently under development, is therefore likely to be important for producing good simulations of tropical variability and extremes in the present day and future.
Imprint of the convective parameterization and sea‐surface temperature on large‐scale convective self‐aggregation
Authors: Becker Tobias , Stevens Bjorn , Hohenegger Cathy
Published: May 2017

Radiative‐convective equilibrium simulations with the general circulation model ECHAM6 are used to explore to what extent the dependence of large‐scale convective self‐aggregation on sea‐surface temperature (SST) is driven by the convective parameterization. Within the convective parameterization, we concentrate on the entrainment parameter and show that large‐scale convective self‐aggregation is independent of SST when the entrainment rate for deep convection is set to zero or when the convective parameterization is removed from the model. In the former case, convection always aggregates very weakly, whereas in the latter case, convection always aggregates very strongly. With a nontrivial representation of convective entrainment, large‐scale convective self‐aggregation depends nonmonotonically on SST. For SSTs below 295 K, convection is more aggregated the smaller the SST because large‐scale moisture convergence is relatively small, constraining convective activity to regions with high wind‐induced surface moisture fluxes. For SSTs above 295 K, convection is more aggregated the higher the SST because entrainment is most efficient in decreasing updraft buoyancy at high SSTs, amplifying the moisture‐convection feedback. When halving the entrainment rate, convection is less efficient in reducing updraft buoyancy, and convection is less aggregated, in particular at high SSTs. Despite most early work on self‐aggregation highlighted the role of nonconvective processes, we conclude that convective self‐aggregation and the global climate state are sensitive to the convective parameterization.
First look at Jupiter's synchrotron emission from Juno's perspective
Authors: Santos‐Costa D. , Adumitroaie V. , Ingersoll A. , Gulkis S. , Janssen M. A. , Levin S. M. , Oyafuso F. , Brown S. , Williamson R. , Bolton S. J. , Connerney J. E. P.
Published: May 2017

Since August 2016, measurements of Jupiter's microwave emissions at six wavelengths ranging from 1.3 cm to 50 cm have been made with the Juno Microwave Radiometer. In this paper, we introduce the first systematic set of in situ observations of synchrotron radiation in a polar plane while describing the modeling approach we use to analyze this data (collected 27 August 2016). Time series of brightness profiles at all six frequencies present similarities that are explained by the presence of known regions of intense synchrotron radiation. Our model predictions, though limited for now to the total intensity of the radiation, reproduce (qualitatively) the observation of temporal variations and allow to disentangle the synchrotron emission from the atmospheric emission. The discrepancies seen between the data and simulations confirm that physical conditions close to Jupiter affecting synchrotron emission (electron energy spectra, pitch angle distributions, and the magnetic environment) are different than we anticipated.
Transient brightening of Jupiter's aurora observed by the Hisaki satellite and Hubble Space Telescope during approach phase of the Juno spacecraft
Authors: Kimura T. , Nichols J. D. , Gray R. L. , Tao C. , Murakami G. , Yamazaki A. , Badman S. V. , Tsuchiya F. , Yoshioka K. , Kita H. , Grodent D. , Clark G. , Yoshikawa I. , Fujimoto M.
Published: May 2017

In early 2014, continuous monitoring with the Hisaki satellite discovered transient auroral emission at Jupiter during a period when the solar wind was relatively quiet for a few days. Simultaneous imaging made by the Hubble Space Telescope (HST) suggested that the transient aurora is associated with a global magnetospheric disturbance that spans from the inner to outer magnetosphere. However, the temporal and spatial evolutions of the magnetospheric disturbance were not resolved because of the lack of continuous monitoring of the transient aurora simultaneously with the imaging. Here we report the coordinated observation of the aurora and plasma torus made by Hisaki and HST during the approach phase of the Juno spacecraft in mid‐2016. On day 142, Hisaki detected a transient aurora with a maximum total H2 emission power of ~8.5 TW. The simultaneous HST imaging was indicative of a large “dawn storm,” which is associated with tail reconnection, at the onset of the transient aurora. The outer emission, which is associated with hot plasma injection in the inner magnetosphere, followed the dawn storm within less than two Jupiter rotations. The monitoring of the torus with Hisaki indicated that the hot plasma population increased in the torus during the transient aurora. These results imply that the magnetospheric disturbance is initiated via the tail reconnection and rapidly expands toward the inner magnetosphere, followed by the hot plasma injection reaching the plasma torus. This corresponds to the radially inward transport of the plasma and/or energy from the outer to the inner magnetosphere.
Response of Jupiter's auroras to conditions in the interplanetary medium as measured by the Hubble Space Telescope and Juno
Authors: Nichols J. D. , Badman S. V. , Bagenal F. , Bolton S. J. , Bonfond B. , Bunce E. J. , Clarke J. T. , Connerney J. E. P. , Cowley S. W. H. , Ebert R. W. , Fujimoto M. , Gérard J.‐C. , Gladstone G. R. , Grodent D. , Kimura T. , Kurth W. S. , Mauk B. H. , Murakami G. , McComas D. J. , Orton G. S. , Radioti A. , Stallard T. S. , Tao C. , Valek P. W. , Wilson R. J. , Yamazaki A. , Yoshikawa I.
Published: May 2017

We present the first comparison of Jupiter's auroral morphology with an extended, continuous, and complete set of near‐Jupiter interplanetary data, revealing the response of Jupiter's auroras to the interplanetary conditions. We show that for ∼1–3 days following compression region onset, the planet's main emission brightened. A duskside poleward region also brightened during compressions, as well as during shallow rarefaction conditions at the start of the program. The power emitted from the noon active region did not exhibit dependence on any interplanetary parameter, though the morphology typically differed between rarefactions and compressions. The auroras equatorward of the main emission brightened over ∼10 days following an interval of increased volcanic activity on Io. These results show that the dependence of Jupiter's magnetosphere and auroras on the interplanetary conditions are more diverse than previously thought.
The analysis of initial Juno magnetometer data using a sparse magnetic field representation
Authors: Moore Kimberly M. , Bloxham Jeremy , Connerney John E. P. , Jørgensen John L. , Merayo José M. G.
Published: May 2017

The Juno spacecraft, now in polar orbit about Jupiter, passes much closer to Jupiter's surface than any previous spacecraft, presenting a unique opportunity to study the largest and most accessible planetary dynamo in the solar system. Here we present an analysis of magnetometer observations from Juno's first perijove pass (PJ1; to within 1.06 RJ of Jupiter's center). We calculate the residuals between the vector magnetic field observations and that calculated using the VIP4 spherical harmonic model and fit these residuals using an elastic net regression. The resulting model demonstrates how effective Juno's near‐surface observations are in improving the spatial resolution of the magnetic field within the immediate vicinity of the orbit track. We identify two features resulting from our analyses: the presence of strong, oppositely signed pairs of flux patches near the equator and weak, possibly reversed‐polarity patches of magnetic field over the polar regions. Additional orbits will be required to assess how robust these intriguing features are.
A planetary‐scale disturbance in the most intense Jovian atmospheric jet from JunoCam and ground‐based observations
Authors: Sánchez‐Lavega A. , Rogers J. H. , Orton G. S. , García‐Melendo E. , Legarreta J. , Colas F. , Dauvergne J. L. , Hueso R. , Rojas J. F. , Pérez‐Hoyos S. , Mendikoa I. , Iñurrigarro P. , Gomez‐Forrellad J. M. , Momary T. , Hansen C. J. , Eichstaedt G. , Miles P. , Wesley A.
Published: May 2017

We describe a huge planetary‐scale disturbance in the highest‐speed Jovian jet at latitude 23.5°N that was first observed in October 2016 during the Juno perijove‐2 approach. An extraordinary outburst of four plumes was involved in the disturbance development. They were located in the range of planetographic latitudes from 22.2° to 23.0°N and moved faster than the jet peak with eastward velocities in the range 155 to 175 m s−1. In the wake of the plumes, a turbulent pattern of bright and dark spots (wave number 20–25) formed and progressed during October and November on both sides of the jet, moving with speeds in the range 100–125 m s−1 and leading to a new reddish and homogeneous belt when activity ceased in late November. Nonlinear numerical models reproduce the disturbance cloud patterns as a result of the interaction between local sources (the plumes) and the zonal eastward jet.
Preliminary JIRAM results from Juno polar observations: 3. Evidence of diffuse methane presence in the Jupiter auroral regions
Authors: Moriconi M. L. , Adriani A. , Dinelli B. M. , Fabiano F. , Altieri F. , Tosi F. , Filacchione G. , Migliorini A. , Gérard J. C. , Mura A. , Grassi D. , Sindoni G. , Piccioni G. , Noschese R. , Cicchetti A. , Bolton S. J. , Connerney J. E. P. , Atreya S. K. , Bagenal F. , Gladstone G. R. , Hansen C. , Kurth W. S. , Levin S. M. , Mauk B. H. , McComas D. J. , Turrini D. , Stefani S. , Olivieri A. , Amoroso M.
Published: May 2017

Throughout the first orbit of the NASA Juno mission around Jupiter, the Jupiter InfraRed Auroral Mapper (JIRAM) targeted the northern and southern polar regions several times. The analyses of the acquired images and spectra confirmed a significant presence of methane (CH4) near both poles through its 3.3 μm emission overlapping the H3+ auroral feature at 3.31 μm. Neither acetylene (C2H2) nor ethane (C2H6) have been observed so far. The analysis method, developed for the retrieval of H3+ temperature and abundances and applied to the JIRAM‐measured spectra, has enabled an estimate of the effective temperature for methane peak emission and the distribution of its spectral contribution in the polar regions. The enhanced methane inside the auroral oval regions in the two hemispheres at different longitude suggests an excitation mechanism driven by energized particle precipitation from the magnetosphere.
Juno's first glimpse of Jupiter's complexity
Authors: Bolton Scott , Levin Steven , Bagenal Fran
Published: May 2017

Preliminary results from NASA's Juno mission are presented in this special issue of Geophysical Research Letters. The data were gathered by nine scientific instruments as the Juno spacecraft approached Jupiter on the dawn flank, was inserted into Jupiter orbit on 4 July 2016, and made the first polar passes close to the planet. The first results hint that Jupiter may not have a distinct core, indicate puzzling deep atmospheric convection, and reveal complex small‐scale structure in the magnetic field and auroral processes that are distinctly different from those at Earth.
Electron density variability of nighttime D region ionosphere in Vietnamese and Japanese sectors
Authors: Tan Le Minh , Shiokawa Kazuo , Thu Nguyen Ngoc , Ha Tran Quoc
Published: May 2017

Recording tweek atmospherics on geomagnetically quiet days in 2014 at Tay Nguyen University (TNU) (12.65°N, 108.02°E), Vietnam, and at Kagoshima (KAG) (31.48°N, 130.72°E), Japan, we investigated the nighttime electron density variability of the D region ionosphere between the equatorial‐low‐latitude Vietnamese and the low‐ to middle‐latitude Japanese sectors. We estimated the reflection height and electron density of the D region ionosphere using the first‐order mode cutoff frequency of tweek atmospherics. The results observed at both stations show that the mean electron density at the reflection height during winter season was higher than that during summer and equinox seasons. The electron density observed at TNU gradually decreased from 20:15 to 4:15 LT from winter to equinox and to summer. The electron density observed at KAG increased from 20:20 to 4:20 LT during summer and winter seasons. The mean electron density during 2014 observed at TNU (25.0 cm−3) was higher by 2.1 cm−3 than that observed at KAG (22.9 cm−3). During 2014, the nighttime electron density variations show a moderate positive correlation with the sunspot number but show weak to no correlation with the galactic cosmic rays. We suggest that the seasonal variations in the nighttime electron density could be significantly caused by the enhancement of geocoronal hydrogen Lyman α intensity and seasonal variation of nitric oxide density in the lower ionosphere.
Warm layer and cool skin corrections for bulk water temperature measurements for air‐sea interaction studies
Authors: Alappattu Denny P. , Wang Qing , Yamaguchi Ryan , Lind Richard J. , Reynolds Mike , Christman Adam J.
Published: May 2017

The sea surface temperature (SST) relevant to air‐sea interaction studies is the temperature immediately adjacent to the air, referred to as skin SST. Generally, SST measurements from ships and buoys are taken at depths varies from several centimeters to 5 m below the surface. These measurements, known as bulk SST, can differ from skin SST up to O(1°C). Shipboard bulk and skin SST measurements were made during the Coupled Air‐Sea Processes and Electromagnetic ducting Research east coast field campaign (CASPER‐East). An Infrared SST Autonomous Radiometer (ISAR) recorded skin SST, while R/V Sharp's Surface Mapping System (SMS) provided bulk SST from 1 m water depth. Since the ISAR is sensitive to sea spray and rain, missing skin SST data occurred in these conditions. However, SMS measurement is less affected by adverse weather and provided continuous bulk SST measurements. It is desirable to correct the bulk SST to obtain a good representation of the skin SST, which is the objective of this research. Bulk‐skin SST difference has been examined with respect to meteorological factors associated with cool skin and diurnal warm layers. Strong influences of wind speed, diurnal effects, and net longwave radiation flux on temperature difference are noticed. A three‐step scheme is established to correct for wind effect, diurnal variability, and then for dependency on net longwave radiation flux. Scheme is tested and compared to existing correction schemes. This method is able to effectively compensate for multiple factors acting to modify bulk SST measurements over the range of conditions experienced during CASPER‐East.
IFITM1 suppresses expression of human endogenous retroviruses in human embryonic stem cells
Authors: Fu Yudong , Zhou Zhongcheng , Wang Hua , Gong Peng , Guo Renpeng , Wang Jinmiao , Lu Xinyi , Qi Feng , Liu Lin
Published: May 2017

Interferon‐induced transmembrane protein 1 (IFITM1), a member of the IFITM protein family, is a component of a multimeric complex involved in the transduction of antiproliferation and cell adhesion signals. IFITM1 is thought to play a role in antiproliferation and immune surveillance, and has been shown to restrict infection by numerous viruses. It is highly expressed in human embryonic stem cells (hESCs) but its role in hESCs remains to be elucidated. In this study, knockout of IFITM1 mediated by CRISPR/Cas9 in hESCs did not affect self‐renewal, pluripotency, telomerase activity or telomeres. However expression of human endogenous retroviruses (HERVs) was higher than in wild‐type hESCs, and there was also a reduced level of trimethylation of histone H3 on lysine 9 at HERV loci. These data show that IFITM1 suppresses HERVs in hESCs by regulating epigenetic modifications.
Icing detection and identification for unmanned aerial vehicles using adaptive nested multiple models
Authors: Cristofaro Andrea , Johansen Tor Arne , Aguiar A. Pedro
Published: May 2017

A multiple‐model approach for icing diagnosis and identification in small unmanned aerial vehicles is proposed. The accretion of ice layers on wings and control surfaces modifies the shape of the aircraft and, consequently, alters the performance and controllability of the vehicle. Pitot tubes might be blocked due to icing, providing errors in the airspeed measurements. In this paper, we propose a nested multiple‐model adaptive estimation framework to detect and estimate icing using standard sensors only, ie, a pitot tube and an inertial measurement unit. The architecture of the estimation scheme is based on 2 different time scales, ie, one for the accretion of ice on aircraft surfaces and one for the accretion of ice on sensors, and consists of 2 nested adaptive observers, namely, outer and inner loops, respectively. The case study of a typical small unmanned aerial vehicle supports and validates the proposed theoretical results.
Double closed‐loop control with adaptive strategy for automotive engine speed tracking system
Authors: Feng Meiyu , Jiao Xiaohong
Published: May 2017

In order to improve the transient and static performances of an engine speed control system in a wide speed range, this paper presents an adaptive double closed‐loop control strategy. The control scheme possesses intake manifold pressure inner closed‐loop adaptive proportional‐integral control and engine speed outer closed‐loop adaptive proportional‐integral control for achieving the tracking precision in a wide range of speed, as well as adaptive nonlinearity and feedforward compensators for overcoming parameter uncertainty and nonlinearity. The whole closed‐loop system's stability and the speed tracking convergence are ensured theoretically by the Lyapunov stability theory and the LaSalle invariant principle. The effectiveness of the proposed control strategy is validated through the operation results on the simulator of a V6 engine exploited by the Research Committee of the Society of Instrument and Control Engineers of Japan.
Screening of Nanocomposite Scaffolds Arrays Using Superhydrophobic‐Wettable Micropatterns
Authors: Leite Álvaro J. , Oliveira Mariana B. , Caridade Sofia G. , Mano João F.
Published: May 2017

Platforms containing multiple arrays for high‐throughput screening are demanded in the development of biomaterial libraries. Here, an array platform for the combinatorial analysis of cellular interactions and 3D porous biomaterials is described. Using a novel method based on computer‐aided manufacturing, wettable regions are printed on superhydrophobic surfaces, generating isolated spots. This freestanding benchtop array is used as a tool to deposit naturally derived polymers, chitosan and hyaluronic acid, with bioactive glass nanoparticles (BGNPs) to obtain a scaffold matrix. The effect of fibronectin adsorption on the scaffolds is also tested. The biomimetic nanocomposite scaffolds are shown to be osteoconductive, non‐cytotoxic, promote cell adhesion, and regulate osteogenic commitment. The method proves to be suitable for screening of biomaterials in 3D cell cultures as it can recreate a multitude of combinations on a single platform and identify the optimal composition that drives to desired cell responses. The platforms are fully compatible with commercially routine cell culture labware and established characterization methods, allowing for a standard control and easy adaptability to the cell culture environment. This study shows the value of 3D structured array platforms to decode the combinatorial interactions at play in cell microenvironments.
Flexible PbZr0.52Ti0.48O3 Capacitors with Giant Piezoelectric Response and Dielectric Tunability
Authors: Gao Wenxiu , You Lu , Wang Yaojin , Yuan Guoliang , Chu Ying‐Hao , Liu Zhiguo , Liu Jun‐Ming
Published: May 2017

Oxide ferroelectric ceramics and single crystals for flexible wearable device applications significantly suffer from the nature of hardness and brittleness due to their small maximum elastic strain and technological challenge in thinning to micrometer or nanometer scale. Although many oxide films are thin enough to be flexible, their rigid substrates restrain their piezoelectric d33 coefficient and limit their flexible performance. Here, the large‐scale PbZr0.52Ti0.48O3 (PZT) films with SrRuO3 (SRO) buffered layer are grown on the 10 µm thick flexible mica substrate. An amplified longitudinal piezoelectric d33 of about 1200 pm V−1 is achieved in an SRO/PZT/Pt capacitor due to the direct mechanical coupling between PZT and flexible mica via the d31 piezoelectric tensor. The SRO/PZT/Pt capacitor shows a saturated polarization of ≈60 µC cm−2 and a dielectric tunability of ≈90%. Most importantly, the electric properties do not show obvious deterioration after repeatedly bending 10 000 times at a 2.2 mm radius. The flexible ferroelectric capacitors have potential applications in next‐generation wearable devices and micro‐electromechanical systems.
Doping‐Free Asymmetrical Silicon Heterocontact Achieved by Integrating Conjugated Molecules for High Efficient Solar Cell
Authors: Liu Jiawei , Ji Yujin , Liu Yuqiang , Xia Zhouhui , Han Yujie , Li Youyong , Sun Baoquan
Published: May 2017

Organic conjugated molecule/silicon (Si) heterojunction has been widely investigated to build up an asymmetrical heterocontact for efficient photovoltaics. However, it is still unclear how the organic molecular structures can affect their electronic coupling interaction with Si. Here, two widely explored electron acceptors of poly{[N,N′‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)} (N2200) and [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) are used to build up asymmetrical Si heterocontact to investigate their electronic coupling interaction. It is found that PCBM displays different electronic coupling with Si from N2200, which is ascribed to their various physical distance with Si based on a systematic and detailed density functional theory calculation. Organic layer incorporation not only suppresses the surface charge recombination velocity but also leads to an Ohmic contact between Si and Al. Therefore, a doping‐free organic/Si heterojunction photovoltaic with a power conversion efficiency of 14.9% is achieved with PCBM layer. This work discloses a key factor affecting organic/Si electronic coupling interaction, which helps build up high quality Si heterocontact for solar cells and other optoelectronic devices. Furthermore, the simplified heterocontact achieved by a low temperature, solution processed, and lithography‐free steps has a dramatic improvement on conventional diffusion doped‐silicon one at high temperature.
Thaumatin and gum arabic allergy in chewing gum factory workers
Authors: Tschannen Mattias P. , Glück Ulrich , Bircher Andreas J. , Heijnen Ingmar , Pletscher Claudia
Published: May 2017

Thaumatin is a sweetener and flavor modifier commonly used in the food industry. Likewise, gum arabic is widely used as a food stabilizer and thickening agent. We report here that a powder mixture composed of 10% thaumatin and 90% gum arabic led to allergic symptoms in the upper airways in occupationally exposed individuals: four of eight workers of a chewing gum factory exposed to this powder mixture had pronounced rhinitis. A positive skin prick test result for pure thaumatin was obtained in all four individuals with rhinitis of whom two also had a positive skin prick test result for pure gum arabic and gum arabic‐specific IgE. Subsitution of a powdered thaumatin with a liquid form reduced symptoms among the rhinitic workers. Although gum arabic is a well‐known potential allergen, we were unable to find prior documentation of allergic symptoms to thaumatin when it is used in the food industry.
A mutation in GABRB3 associated with Dravet syndrome
Authors: Le Sy Vinh , Le Phan Hoang Truc , Le Thi Khanh Van , Kieu Huynh Thi Thuy , Hang Do Thi Thu
Published: May 2017

Dravet syndrome is a rare and severe type of epilepsy in infants. Approximately, 70–80% of patients with Dravet syndrome have mutations in SCN1A, the gene encoding the alpha‐1 subunit of the sodium channel, while some simplex patients have variants in one of several other genes, including but not limited to GABRA1, SCN2A, STXBP1, GABRG2, and SCN1B. In this study, we performed exome sequencing in six patients with SCN1A‐negative Dravet syndrome to identify other genes related to this disorder. In one affected individual, we detected a novel de novo heterozygous missense variant, c.695G>A, p.(Arg232Gln), in GABRB3, the gene encoding the β3‐subunit of the gamma‐aminobutyric acid type A (GABAA) receptor, which mediates inhibitory signaling within the central nervous system. In summary, the data in this study identify GABRB3 as a candidate gene for Dravet syndrome.
Haploinsufficiency of NR4A2 is associated with a neurodevelopmental phenotype with prominent language impairment
Authors: Reuter Miriam S. , Krumbiegel Mandy , Schlüter Gregor , Ekici Arif B. , Reis André , Zweier Christiane
Published: May 2017

Non‐recurrent deletions in 2q24.1, minimally overlapping two genes, NR4A2 and GPD2, were recently described in individuals with language impairment and behavioral and cognitive symptoms. We herewith report on a female patient with a similar phenotype of severe language and mild cognitive impairment, in whom we identified a de novo deletion covering only NR4A2. NR4A2 encodes a transcription factor highly expressed in brain regions critical for speech and language and implicated in dopaminergic neuronal development. Our findings of a de novo deletion of NR4A2 in an individual with mild intellectual disability and prominent speech and language impairment provides further evidence for NR4A2 haploinsufficiency being causative for neurodevelopmental and particularly language phenotypes.
Cs‐Symmetric Donor–Acceptor Bis(thiazole)s: Synthesis and Photophysical, Electrochemical, and Computational Studies
Authors: Maragani Ramesh , Bijesh S. , Sharma Rekha , Misra Rajneesh
Published: May 2017

We herein report the design and synthesis of Cs‐symmetric donor–acceptor (D–A) molecular systems that have electron‐donating and electron‐withdrawing groups of the type D‐π‐A‐π‐D and D‐A1‐A‐A1‐D by using a Pd‐catalyzed Sonogshira cross‐coupling and [2+2] cycloaddition–retroelectrocyclization reactions. The photophysical and electrochemical properties as well as computational studies of these systems were explored, and strong donor–acceptor interactions were found. The [2+2] cycloaddition–retroelectrocyclization reaction pathway was studied by computational calculations, which revealed that bis(thiazole)s that contain donor groups at the terminal positions were favored in the reaction with tetracyanoethene (TCNE), whereas bis(thiazole)s that contain electron‐withdrawing groups were disfavored.
Behavioral inferences from the high levels of dental chipping in Homo naledi
Authors: Towle Ian , Irish Joel D. , De Groote Isabelle
Published: May 2017

Objectives

A variety of mechanical processes can result in antemortem dental chipping. In this study, chipping data in the teeth of Homo naledi are compared with those of other pertinent dental samples to give insight into their etiology.

Materials and methods

Permanent teeth with complete crowns evidencing occlusal wear were examined macroscopically. The location, number, and severity of fractures were recorded and compared to those found in samples of two other South African fossil hominin species and in samples of nonhuman primates (n = 3) and recent humans (n = 7).

Results

With 44% of teeth affected, H. naledi exhibits far higher rates of chipping than the other fossil hominin samples. Specifically, 50% of posterior teeth and 31% of anterior teeth display at least one chip. The maxillary teeth are more affected than the mandibular teeth (45% vs 43%, respectively), 73% of molar chipping occurs on interproximal surfaces, and right teeth are more often affected than left teeth (50% vs 38%).

Discussion

Results indicate that the teeth of H. naledi were exposed to acute trauma on a regular basis. Because interproximal areas are more affected than buccal and posterior teeth more than anterior, it is unlikely that nonmasticatory cultural behavior was the cause. A diet containing hard and resistant food, or contaminants such as grit, is more likely. The small chip size, and steep occlusal wear and cupped dentine on some molars are supportive of the latter possibility. This pattern of chipping suggests that H. naledi differed considerably—in terms of diet, environment, and/or specialized masticatory processing—relative to other African fossil hominins.
Household pet exposure, allergic sensitization, and rhinitis in the U.S. population
Authors: Shargorodsky Josef , Garcia‐Esquinas Esther , Umanskiy Rachel , Navas‐Acien Ana , Lin Sandra Y.
Published: May 2017

Background

The effect of animal dander exposure on allergic sensitization may be age‐dependent. A comparison between the association of the levels of exposure to pet allergen with rhinitis symptoms and allergic sensitization in children and adults is yet to be performed in the U.S. population.

Methods

Cross‐sectional study of 3034 adults (age, 20 to 85 years) and 2104 children (age, 6 to 19 years) in the National Health and Nutrition Examination Survey, 2005–2006. Samples of household dust were collected to measure the amounts of indoor allergens in the participants’ homes. Self‐reported rhinitis was based on symptoms during the past 12 months, and allergen sensitization was defined as a positive response to any of the 19 specific immunoglobulin E (IgE) antigens tested.

Results

Higher levels of exposure to dog dander were associated with a higher prevalence of any allergic sensitization in adults (prevalence ratio [PR] 1.19; 95% confidence interval [CI], 1.01 to 1.39), but a lower prevalence in children (PR 0.84; 95% CI, 0.73 to 0.096), p‐interaction by age group 0.02. Cat exposure was associated with an increased prevalence of rhinitis symptoms in adults (PR for the 3rd vs lowest tertile of cat dander concentrations: 1.14; 95% CI, 1.05 to 1.23) but not in children (PR for the 3rd vs lowest tertile of cat dander IgE concentrations: 0.86; 95% CI, 0.70 to 1.07), p‐interaction 0.01.

Conclusion

Allergic sensitization and symptomatic response to pet dander exposure may vary based on age. Further studies are necessary to assess the mechanisms for these apparent differences.
Relative susceptibility of airway organisms to antimicrobial effects of nitric oxide
Authors: Workman Alan D. , Carey Ryan M. , Kohanski Michael A. , Kennedy David W. , Palmer James N. , Adappa Nithin D. , Cohen Noam A.
Published: May 2017

Background

Nitric oxide (NO) is released in the airway as a critical component of innate immune defense against invading pathogenic organisms. It is well documented that bacteriostatic and bactericidal effects of NO are concentration‐dependent. However, few data exist comparing relative susceptibility of common pathogens to NO at physiologic concentrations. In this study we evaluated the effects of NO on 4 common airway bacteria and 1 fungus, and examined the potential implications of discrepancies in sensitivity.

Methods

Staphylococcus epidermis, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Candida albicans cultures were adjusted to a uniform optical density (OD) and grown in log phase at 37°C with varying concentrations of NO formed by DETA NONOate. Both OD readings and colony forming units (CFUs) were measured at varying time‐points to evaluate for inhibitory effects of NO.

Results

P aeruginosa and C albicans were significantly more sensitive to NO at physiologic concentrations typical of the human airway. S aureus was attenuated by NO to a lesser degree, and K pneumoniae and S epidermis were more resistant to NO at all concentrations tested. Air surface liquid from cultured human sinonasal epithelial cells had an additive effect in bacterial killing of P aeruginosa, but not in S aureus.

Conclusion

Common airway pathogens have varying levels of susceptibility to NO at physiologic concentrations of innate immune defense. Relative sensitivity of P aeruginosa and relative resistance of S epidermis may help explain the composition of the healthy microbiome, as well as opportunistic infection in the absence of induced NO release.
A Unified Continuous Flow Assembly‐Line Synthesis of Highly Substituted Pyrazoles and Pyrazolines
Authors: Britton Joshua , Jamison Timothy F.
Published: May 2017

A rapid and modular continuous flow synthesis of highly functionalized fluorinated pyrazoles and pyrazolines has been developed. Flowing fluorinated amines through sequential reactor coils mediates diazoalkane formation and [3+2] cycloaddition to generate more than 30 azoles in a telescoped fashion. Pyrazole cores are then sequentially modified through additional reactor modules performing N‐alkylation and arylation, deprotection, and amidation to install broad molecular diversity in short order. Continuous flow synthesis enables the safe handling of diazoalkanes at elevated temperatures, and the use of aryl alkyne dipolarphiles under catalyst‐free conditions. This assembly‐line synthesis provides a flexible approach for the synthesis of agrochemicals and pharmaceuticals, as demonstrated by a four‐step, telescoped synthesis of measles therapeutic, AS‐136A, in a total residence time of 31.7 min (1.76 g h−1).
Theoretical Treatment of CH3NH3PbI3 Perovskite Solar Cells
Authors: Yun Sining , Zhou Xiao , Even Jacky , Hagfeldt Anders
Published: May 2017

Hybrid halide perovskite solar cells (PSCs) giving over 22 % power conversion efficiencies (PCEs) have attracted considerable attention. Although perovskite plays a significant role in the operation of PSCs, the fundamental theories associated with perovskites have not been resolved in spite of the increase in research. In this Minireview, we assess the current understanding, based on the first‐principles calculations, of structural and electronic properties, defects, ionic diffusion, and shift current for CH3NH3PbI3 perovskite, and the effect of ionic transport on the hysteresis of current–voltage curves in PSCs. The shift current connected to the possible presence of ferroelectricity is also discussed. The current state‐of‐the‐art and some open questions regarding PSCs are also highlighted, and the benefits, challenges, and potentials of perovskite for use in PSCs are stressed.
Control of Product Distribution and Mechanism by Ligation and Electric Field in the Thermal Activation of Methane
Authors: Yue Lei , Li Jilai , Zhou Shaodong , Sun Xiaoyan , Schlangen Maria , Shaik Sason , Schwarz Helmut
Published: May 2017

An unexpected mechanistic switch as well as a change of the product distribution in the thermal gas‐phase activation of methane have been identified when diatomic [ZnO].+ is ligated with acetonitrile. Theoretical studies suggest that a strong metal–carbon attraction in the pristine [ZnO].+ species plays an important role in the rebound of the incipient CH3. radical to the metal center, thus permitting the competitive generation of CH3., OH., and CH3OH. This interaction is drastically weakened by a single CH3CN ligand. As a result, upon ligation the proton‐coupled single electron transfer that prevails for [ZnO].+/CH4 switches to the classical hydrogen‐atom‐transfer process, thus giving rise to the exclusive expulsion of CH3.. This ligand effect can be modeled quite well by an oriented external electric field of a negative point charge.
Molecular Graph Paper
Authors: Lindner Marcin , Valášek Michal , Mayor Marcel , Frauhammer Timo , Wulfhekel Wulf , Gerhard Lukas
Published: May 2017

We present a self‐assembled template that consists of tetraphenylmethane derivatives and adopts a periodic lateral arrangement on a Au(111) surface with acetyl groups sticking out of the molecular film. By using the tip of a scanning tunneling microscope, these acetyl groups can be removed in a spatially controlled way without significantly affecting the remaining molecular assembly. The chemically modified molecules can be readily distinguished from the original ones such that information can be engraved in the molecular film. Both the modified nature of an individual molecule and the order of the molecular film are shown to persist at room temperature. The mesh size of this molecular graph paper can be tuned by varying the length of the molecular spacer so that writing and reading information on the nanoscale with variable letter sizes becomes possible.
Magnetic copper ferrite catalyzed homo‐ and cross‐coupling reaction of terminal alkynes under ambient atmosphere
Authors: Ma Cui‐Ting , Wang Jiao‐Jiao , Zhao Ai‐Dong , Wang Qing‐Li , Zhang Zhan‐Hui
Published: May 2017

The application of non‐toxic and magnetically separable nano‐CuFe2O4 as an efficient catalyst for oxidative homo‐ and cross‐coupling reaction of terminal alkynes is described. A wide range of symmetrical and unsymmetrical 1,3‐diynes have been synthesized in moderate to good yields under ambient atmosphere. The nano CuFe2O4 can be recovered with a magnet and reused at least five consecutive cycles with no appreciable loss of its catalytic activity.
A refined model for the mechanical properties of polymer composites with nanorods having different length distributions
Authors: Sapkota Janak , Gooneie Ali , Shirole Anuja , Martinez Garcia Julio Cesar
Published: May 2017

The aspect ratio of rod‐like nanofillers is an important factor that governs their percolation threshold in nanocomposites with a polymer of interest. Controlling the length distribution of a filler is an effective way to manipulate the onset of network formation and thereby materials properties that are related to the latter. The use of two or more different filler types with dissimilar aspect ratio is a special case to achieve such control. We here report the modification of an existing mechanical model to describe the mechanical properties of polymer nanocomposites with a binary length distribution of nanofillers. The model was exemplarily applied to materials comprised of two nanorod types having high and low aspect ratio, respectively, and used to explain why the properties of such nanocomposites are strongly weighted by the nanorod type characterized by a higher aspect ratio and stiffness. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45279.
Influence of microstructure of lactone‐based triblock copolymers on drug release behavior of their microspheres
Authors: Kasyapi Nibedita , Dinesh Kumar K. , Bhowmick Anil K.
Published: May 2017

The current work focuses on the influence of microstructure of different lactone‐based triblock copolymers on drug delivery, where the middle segment was δ‐valerolactone or ɛ‐caprolactone and the terminal segment was d,l‐lactide or cis‐lactide. Microspheres were fabricated from the triblocks using salicylic acid as the model drug. The microsphere formation and drug release were investigated by scanning electron microscopy, ultraviolet–visible spectroscopy, X‐ray diffraction, and thermogravimetry. The size of the microspheres ranged from 2 to 20 µm in diameter. The diffusion coefficient values showed that replacement of the middle segment, δ‐valerolactone with ɛ‐caprolactone, retarded the diffusion of the drug molecules. The diffusion coefficient was lowered when d,l‐lactide content was decreased in the triblock. Mathematical models were used to predict the drug release from the microspheres of different triblocks. The modeling study on drug release profiles revealed that the biodegradable nature of the triblock played a crucial role in determining the drug release kinetics. The diffusion and degradation reaction justified the drug release from microsphere. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45284.
Matched control groups for modeling events in citation data: An illustration of nobel prize effects in citation networks
Authors: Farys Rudolf , Wolbring Tobias
Published: May 2017

Bibliometric data are frequently used to study the effects of events, such as the honoring of a scholar with an award, and to investigate changes of citation impact over time. However, the number of yearly citations depends upon time for multiple reasons: a) general time trends in citation data, b) changing coverage of databases, c) individual citation life‐cycles, and d) selection on citation impact. Hence, it is often ill‐advised to simply compare the average number of citations before and after an event to estimate its causal effect. Using a recent publication in this journal on the potential citation chain reaction of a Nobel Prize, we demonstrate that a simple pre‐post comparison can lead to biased and misleading results. We propose using matched control groups to improve causal inference and illustrate that the inclusion of a tailor‐made synthetic control group in the statistical analysis helps to avoid methodological artifacts. Our results suggest that there is neither a Nobel Prize effect as regards citation impact of the Nobel laureate under investigation nor a related chain reaction in the citation network, as suggested in the original study. Finally, we explain that these methodological recommendations extend far beyond the study of Nobel Prize effects in citation data.
Person Name Disambiguation in the Web Using Adaptive Threshold Clustering
Authors: Delgado Agustín D. , Martínez Raquel , Montalvo Soto , Fresno Víctor
Published: May 2017

In this article, we present a new clustering algorithm for Person Name Disambiguation in web search results. The algorithm groups web results according to the individuals they refer to. The best state‐of‐the‐art approaches require training data in order to learn thresholds for deciding when to group the webpages. However, the ambiguity level of person names on the web could not be previously estimated and the results of those methods strongly depend on the thresholds obtained with the training collections. We present the concept of adaptive threshold, which avoids the need of a previous supervised learning process, depending only on the content of the compared documents to decide if they refer to the same person. We evaluated our approach using three datasets reaching close results to those obtained by the most successful algorithms in the state‐of‐the‐art that require such a learning process, and outperforming the results of those obtained by algorithms that do not require it.
Photoinduced Cyclization of (o‐Alkylbenzoyl)phosphonates to Benzocyclobutenols
Authors: Ishida Naoki , Yano Takaaki , Yuhki Tatsuya , Murakami Masahiro
Published: May 2017

(o‐Alkylbenzoyl)phosphonates readily cyclize to highly strained benzocyclobutenols simply upon irradiation with UV light. The remarkable efficiency is ascribed to the electron‐accepting character of the phosphonate substituent, which facilitates thermal ring closing of the o‐quinodimethane intermediate and suppresses reversion to the starting carbonyl compound.
Cascading Target Tracking Control in Wireless Camera Sensor and Actuator Networks
Authors: Wang Tian , Peng Zhen , Xu Wenzheng , Liang Junbin , Wang Guojun , Tian Hui , Cai Yiqiao , Chen Yonghong
Published: May 2017

Recent years have witnessed the fast development of camera sensor networks (CSNs), but most of the existing research methods are based on homogeneous CSNs, which are not cost‐effective and are hard to evolve from traditional wireless sensor networks (WSNs). In this paper, we focus on the target tracking problem in heterogeneous wireless camera sensor and actuator networks which consists of a large number of common static sensors and a small number of mobile camera sensors. The objective is to control camera sensors to track targets dependably with maximized effective monitoring time and short moving distance. We first design a novel tracking algorithm for tracking one target where multiple camera sensors cooperate with each other to track the target in a cascading scheme. Moreover, this cascading algorithm is extended for a multi‐target scenario in consideration of tracking performance and loading balance for multiple targets. The effectiveness of proposed control algorithms is validated by extensive simulation results, which show that they can achieve high monitoring efficiency and comparatively short moving distance.