bluuebunny/crossref_metadata_2025 huggingface dataset:
High performance red-emitting multiple layer InGaN/GaN quantum dot lasers
Authors: Frost Thomas , Hazari Arnab , Aiello Anthony , Baten Md Zunaid , Yan Lifan , Mirecki-Millunchick Joanna , Bhattacharya Pallab
Published: February 2016

InGaN/GaN self-organized quantum dots can provide useful advantages over quantum wells for the realization of long-wavelength visible light sources because the dots are formed by strain relaxation. A III–nitride based laser emitting in the red (λ ∼ 630 nm), which has not been demonstrated with quantum wells, would be useful for a host of applications. We have investigated the epitaxy and characteristics of self-organized InGaN/GaN multiple layer quantum dots grown by plasma-assisted molecular beam epitaxy and have optimized their properties by tuning the growth parameters. Red-emitting (λ ∼ 630 nm) quantum dots have radiative lifetime ∼2.5 ns and internal quantum efficiency greater than 50%. Edge-emitting red-lasers with multi-dot layers in the active region exhibit an extremely low threshold current density of 1.6 kA/cm2, a high temperature coefficient T
0 = 240 K, and a large differential gain dg/dn = 9 × 10−17 cm2.
Si growth at graphene surfaces on 6H-SiC(0001) substrates
Authors: Sone Junki , Yamagami Tsuyoshi , Nakatsuji Kan , Hirayama Hiroyuki
Published: February 2016

We studied the growth of Si at the surface of epitaxial graphene on 6H-SiC(0001). Characteristic flower-like islands with a thickness of 2 to 3 nm nucleated during the growth from 290 to 420 K. The islands became featureless in growth at higher temperatures. The growth was predominantly governed by diffusion-limited aggregation. The diffusion energy was evaluated to be 0.21 eV from the temperature-dependent decrease in the density of the islands.
A tiny taxonomic thorn: Brevianthus hypocanthidium and Aponardia huerlimannii are one and the same.
Authors: Renner Matt , Engel John J , Vana Jiri
Published: February 2016

Brevianthus hypocanthidium and Aponardia huerlimannii are found to be synonymous and the new combination

Brevianthus huerlimannii is made.
Structure of glycosylated NPC1 luminal domain C reveals insights into NPC2 and Ebola virus interactions
Authors: Zhao Yuguang , Ren Jingshan , Harlos Karl , Stuart David I.
Published: February 2016

Niemann‐pick type C1 (NPC1) is an endo/lysosomal membrane protein involved in intracellular cholesterol trafficking, and its luminal domain C is an essential endosomal receptor for Ebola and Marburg viruses. We have determined the crystal structure of glycosylated NPC1 luminal domain C and find all seven possible sites are glycosylated. Mapping the disease mutations onto the glycosylated structure reveals a potential binding face for NPC2. Knowledge‐based docking of NPC1 onto Ebola viral glycoprotein and sequence analysis of filovirus susceptible and refractory species reveals four critical residues, H418, Q421, F502 and F504, some or all of which are likely responsible for the species‐specific susceptibility to the virus infection.
Nucleotide‐dependent conformational changes of the AAA+ ATPase p97 revisited
Authors: Schuller Jan M. , Beck Florian , Lössl Philip , Heck Albert J. R. , Förster Friedrich
Published: February 2016

The ubiquitous AAA‐ATPase p97 segregates ubiquitylated proteins from their molecular environment. Previous studies of the nucleotide‐dependent conformational changes of p97 were inconclusive. Here, we determined its structure in the presence of ADP, AMP‐PNP, or ATP‐γS at 6.1–7.4 Å resolution using single particle cryo‐electron microscopy. Both AAA domains, D1 and D2, assemble into essentially six‐fold symmetrical rings. The pore of the D1‐ring remains essentially closed under all nucleotide conditions, whereas the D2‐ring shows an iris‐like opening for ADP. The largest conformational changes of p97 are ‘swinging motions’ of the N‐terminal domains, which may enable segregation of ubiquitylated substrates from their environment.
The Cretaceous‐Paleogene boundary deposit in the Gulf of Mexico: Large‐scale oceanic basin response to the Chicxulub impact
Authors: Sanford Jason C. , Snedden John W. , Gulick Sean P. S.
Published: February 2016

Hydrocarbon exploration in the last decade has yielded sufficient data to evaluate the Gulf of Mexico basin response to the Chicxulub asteroid impact. Given its passive marine setting and proximity to the impact structure on the Yucatán Peninsula, the gulf is the premier locale in which to study the near‐field geologic effect of a bolide impact. We mapped a thick (decimeter‐ to hectometer‐scale) deposit of carbonate debris at the Cretaceous‐Paleogene boundary that is ubiquitous in the gulf and readily identifiable on borehole and seismic data. We interpret deposits seen in seismic and borehole data in the deepwater gulf to be predominately muddy debrites with minor turbidites based on cores in the southeastern gulf. Mapping of the deposit in the northern Gulf of Mexico reveals that the impact redistributed roughly 1.05 × 105 km3 of sediment therein and over 1.98 × 105 km3 gulfwide. Deposit distribution suggests that the majority of sediment derived from coastal and shallow‐water environments throughout the gulf via seismic and megatsunamic processes initiated by the impact. The Texas shelf and northern margin of the Florida Platform were significant sources of sediment, while the central and southern Florida Platform underwent more localized platform collapse. The crustal structure of the ancestral gulf influenced postimpact deposition both directly and indirectly through its control on salt distribution in the Louann Salt Basin. Nevertheless, impact‐generated deposition overwhelmed virtually all topography and depositional systems at the start of the Cenozoic, blanketing the gulf with carbonate debris within days.
Impact of model resolution on the simulation of diurnal variations of precipitation over East Asia
Authors: Jin Emilia Kyung , Choi In‐Jin , Kim So‐Young , Han Ji‐Young
Published: February 2016

The impact of model resolution on the simulation of diurnal variations of precipitation over East Asia during the summer monsoon period of 2006 is investigated by conducting a suite of ensemble simulations of three different cumulus parameterization schemes (CPS), which are Kain‐Fritsch, Kain‐Fritsch with a modified trigger function, and Simplified Arakawa‐Schubert, and the convection‐permitting (CP) setting with the Weather Research and Forecasting model. The horizontal resolutions of 50 km, 27 km, and 9 km are applied for each different representation of convection process. Model simulations as a whole are able to mimic the diurnal and semidiurnal cycles with 24 h and 12 h peaks in the morning and the afternoon. However, the simulated afternoon peaks over land are earlier in the CPS runs, while delayed in the CP runs, compared to those observed. The increase of resolution improves the phase and amplitude of diurnal variations in the CP runs due to the explicit representation of the realistic cloud system. In addition, the contribution of nonconvective precipitation from the microphysical process significantly improves the phase of diurnal variations in the CPS runs, especially the afternoon peak over land. The KFtr scheme outperforms other schemes in reproducing the diurnal variations due to the relatively dominant role of nonconvective precipitation. Phase does not change with increasing resolution in the diurnal variations of convective precipitation. Only the modification of the convection scheme, such as the alternative trigger function in the KFtr scheme distinguished from the KF scheme, can make fundamental changes in phase of diurnal variation.
Arctic terrestrial hydrology: A synthesis of processes, regional effects, and research challenges
Authors: Bring A. , Fedorova I. , Dibike Y. , Hinzman L. , Mård J. , Mernild S. H. , Prowse T. , Semenova O. , Stuefer S. L. , Woo M.‐K.
Published: February 2016

Terrestrial hydrology is central to the Arctic system and its freshwater circulation. Water transport and water constituents vary, however, across a very diverse geography. In this paper, which is a component of the Arctic Freshwater Synthesis, we review the central freshwater processes in the terrestrial Arctic drainage and how they function and change across seven hydrophysiographical regions (Arctic tundra, boreal plains, shield, mountains, grasslands, glaciers/ice caps, and wetlands). We also highlight links between terrestrial hydrology and other components of the Arctic freshwater system. In terms of key processes, snow cover extent and duration is generally decreasing on a pan‐Arctic scale, but snow depth is likely to increase in the Arctic tundra. Evapotranspiration will likely increase overall, but as it is coupled to shifts in landscape characteristics, regional changes are uncertain and may vary over time. Streamflow will generally increase with increasing precipitation, but high and low flows may decrease in some regions. Continued permafrost thaw will trigger hydrological change in multiple ways, particularly through increasing connectivity between groundwater and surface water and changing water storage in lakes and soils, which will influence exchange of moisture with the atmosphere. Other effects of hydrological change include increased risks to infrastructure and water resource planning, ecosystem shifts, and growing flows of water, nutrients, sediment, and carbon to the ocean. Coordinated efforts in monitoring, modeling, and processing studies at various scales are required to improve the understanding of change, in particular at the interfaces between hydrology, atmosphere, ecology, resources, and oceans.
The Lamu Basin deepwater fold‐and‐thrust belt: An example of a margin‐scale, gravity‐driven thrust belt along the continental passive margin of East Africa
Authors: Cruciani Francesco , Barchi Massimiliano R.
Published: February 2016

In recent decades, advances in seismic processing and acquisition of new data sets have revealed the presence of many deepwater fold‐and‐thrust belts (DW‐FTBs), often developing along continental passive margins. These kinds of tectonic features have been intensively studied, due to their substantial interest. This work presents a regional‐scale study of the poorly explored Lamu Basin DW‐FTB, a margin‐scale, gravity‐driven system extending for more than 450 km along the continental passive margin of Kenya and southern Somalia (East Africa). A 2‐D seismic data set was analyzed, consisting of both recently acquired high‐quality data and old reprocessed seismic profiles, for the first detailed structural and stratigraphic interpretation of this DW‐FTB. The system originated over an Early to mid‐Cretaceous shale detachment due to a mainly gravity‐spreading mechanism. Analysis of synkinematic strata indicates that the DW‐FTB was active from the Late Cretaceous to the Early Miocene, but almost all of the deformation occurred before the Late Paleocene. The fold‐and‐thrust system displays a marked N‐S variation in width, the northern portion being more than 150 km wide and the southern portion only a few dozen kilometers wide; this along‐strike variation is thought to be related to the complex tectonosedimentary evolution of the continental margin at the Somalia‐Kenya boundary, also reflected in the present‐day bathymetry. Locally, a series of volcanic edifices stopped the basinward propagation of the DW‐FTB. A landward change in the dominant structural style, from asymmetric imbricate thrust sheets to pseudo‐symmetric detachment folds, is generally observed, related to the landward thickening of the detached shales.
Vertically integrated models for coupled two‐phase flow and geomechanics in porous media
Authors: Bjørnarå Tore I. , Nordbotten Jan M. , Park Joonsang
Published: February 2016

Models of reduced dimensionality have been found to be particularly attractive in simulating the fate of injected CO2 in supercritical state in the context of carbon capture and storage. This is motivated by the confluence of three aspects: the strong buoyant segregation of the lighter CO2 phase above water, the relatively long time scales associated with storage, and finally the large aspect ratios that characterize the geometry of typical storage aquifers. However, to date, these models have been confined to considering only the flow problem, as the coupling between reduced dimensionality models for flow and models for geomechanical response has previously not been developed. Herein, we develop a fully coupled, reduced dimension, model for multiphase flow and geomechanics. It is characterized by the aquifer(s) being of lower dimension(s), while the surrounding overburden and underburden being of full dimension. The model allows for general constitutive functions for fluid flow (relative permeability and capillary pressure) and uses the standard Biot coupling between the flow and mechanical equations. The coupled model retains all the simplicities of reduced‐dimensional models for flow, including less stiff nonlinear systems of equations (since the upscaled constitutive functions are closer to linear), longer time steps (since the high grid resolution in the vertical direction can be avoided), and less degrees of freedom. We illustrate the applicability of the new coupled model through both a validation study and a practical computational example.
Mandate a Man to Fish?: Technological advance in cooling systems at U.S. thermal electric plants
Authors: Peredo‐Alvarez Victor M. , Bellas Allen S. , Trainor‐Guitton Whitney J. , Lange Ian
Published: February 2016

Steam‐based electrical generating plants use large quantities of water for cooling. The potential environmental impacts of water cooling systems have resulted in their inclusion in the Clean Water Act's (CWA) Sections 316(a), related to thermal discharges and 316(b), related to cooling water intake. The CWA mandates a technological standard for water cooling systems. This analysis examines how the performance‐adjusted rates of thermal emissions and water withdrawals for cooling units have changed over their vintage and how these rates of change were impacted by imposition of the CWA. Results show that the rate of progress increased for cooling systems installed after the CWA whilethere was no progress previous to it.
Experimentally optimized threading structures of the proton‐coupled folate transporter
Authors: Date Swapneeta S. , Chen Cheng‐Yen Charles , Chen Yidong , Jansen Michaela
Published: February 2016

The proton‐coupled folate transporter (PCFT, SLC46A1) transports folic acid across the plasma membrane, together with an excess of protons such that the net charge translocation is positive. We developed 3D structural models of PCFT threaded onto the X‐ray structures of major facilitator superfamily (MFS) members that were identified as close structural homologues. The model of PCFT threaded onto the glycerol‐3‐phosphate transporter (GlpT) structure is consistent with detailed accessibility studies in the absence of extracellular substrate and at pH 7.4 presented here, and additionally with a multitude of other mutagenesis and functional studies. Characteristic MFS structural features are preserved in this PCFT model, such as 12 transmembrane helices divided into two pseudosymmetric bundles, and a high density of positive charges on the periphery of the cytoplasmic site that allow interactions with negatively charged lipid head‐groups. Under the experimental conditions, PCFT predominantly samples the resting state, which in this case is inward‐open. Several positions lining the substrate cavity have been identified. Motif A, a helix‐turn‐helix motif that is a hallmark of MFS transporters between transmembrane segments II and III is oriented appropriately to interact with residues from transmembrane segments IV as well as XI upon conformational transition to the outward‐open state. A charge‐relay system between three charged residues as well as apposing glycines in two α‐helices, both contributed to by motif A, become engaged when PCFT is modeled on the outward‐open state of a putative proton‐driven transporter (YajR).
Psychometric examination and validation of the aggressive driving scale (ADS)
Authors: Zhang Yiqi , Houston Rebecca , Wu Changxu
Published: February 2016

Aggressive driving behavior is an important cause of traffic accidents. Based on the recent view that aggressive driving is one way that trait aggression manifests itself, a growing research area has focused on the development of scales to assess aggressive driving. The aggressive driving scale (ADS) analyzed in the present study consists of 24 items. A sample of 276 participants was analyzed to obtain the factor structure and reliability of the ADS and 67 of them participated in the behavioral experiment in order to examine the construct and predictive validity of the scale. Results indicated a 3‐factor structure (interference with other drivers, violations/risk taking, and anger/aggression expression behavior) with high item loadings. The ADS had high internal consistency and test–retest reliability. Construct validity of the ADS was established as the ADS subscale scores correlated significantly with trait measures of anger and aggression. Predictive validity of the ADS was verified as most items were significantly correlated with behavioral measures derived from a driving simulator. The ADS was a significant predictor of behavioral measures both in the simulated environment (i.e., frequency of driving off the road, red light running behavior, frequency of colliding with a vehicle, frequency and distance of over speeding, frequency and distance of central crossing) and reported real world situations (i.e., annual moving violations and accidents). These results suggest that the ADS is a reliable and valid tool in evaluating aggressive driving behavior as the current study provides behavioral support for the effectiveness of the ADS in measuring aggressive driving behavior. Aggr. Behav. 42:313–323, 2016. © 2016 Wiley Periodicals, Inc.
Emergent Noncentrosymmetry and Piezoelectricity Driven by Oxygen Octahedral Rotations in n = 2 Dion–Jacobson Phase Layer Perovskites
Authors: Strayer Megan E. , Gupta Arnab Sen , Akamatsu Hirofumi , Lei Shiming , Benedek Nicole A. , Gopalan Venkatraman , Mallouk Thomas E.
Published: February 2016

The loss of centrosymmetry via oxygen octahedral rotations is demonstrated in the n = 2 Dion–Jacobson family of layered oxide perovskites, A′LaB2O7 (A′ = Rb, Cs; B = Nb, Ta). Ab initio density functional theory calculations predict that all four materials should adopt polar space groups, in contrast to the results of previous experimental studies that have assigned these materials to the centrosymmetric P4/mmm space group. Optical second harmonic generation experiments confirm the presence of a noncentrosymmetric phase at ambient temperature. Piezoresponse force microscopy experiments also show that this phase is piezoelectric. To elucidate the symmetry‐breaking and assign the appropriate space groups, the crystal structure of CsLaNb2O7 is refined as a function of temperature from synchrotron X‐ray diffraction data. Above 550 K, CsLaNb2O7 adopts the previously determined centrosymmetric P4/mmm space group. Between 550 and 350 K, the symmetry is lowered to the noncentrosymmetric space group Amm2. Below 350 K, additional symmetry lowering is observed as peak splitting, but the space group cannot be unambiguously identified.
Light and Strong SiC Networks
Authors: Ferraro Claudio , Garcia‐Tuñon Esther , Rocha Victoria G. , Barg Suelen , Fariñas Maria Dolores , Alvarez‐Arenas Tomas E. Gomez , Sernicola Giorgio , Giuliani Finn , Saiz Eduardo
Published: February 2016

The directional freezing of microfiber suspensions is used to assemble highly porous (porosities ranging between 92% and 98%) SiC networks. These networks exhibit a unique hierarchical architecture in which thin layers with honeycomb‐like structure and internal strut length in the order of 1–10 μm in size are aligned with an interlayer spacing ranging between 15 and 50 μm. The resulting structures exhibit strengths (up to 3 MPa) and stiffness (up to 0.3 GPa) that are higher than aerogels of similar density and comparable to other ceramic microlattices fabricated by vapor deposition. Furthermore, this wet processing technique allows the fabrication of large‐size samples that are stable at high temperature, with acoustic impedance that can be manipulated over one order of magnitude (0.03–0.3 MRayl), electrically conductive and with very low thermal conductivity. The approach can be extended to other ceramic materials and opens new opportunities for the fabrication of ultralight structures with unique mechanical and functional properties in practical dimensions.
Liquid‐Exfoliated Black Phosphorous Nanosheet Thin Films for Flexible Resistive Random Access Memory Applications
Authors: Hao Chunxue , Wen Fusheng , Xiang Jianyong , Yuan Shijun , Yang Bingchao , Li Lei , Wang Wenhong , Zeng Zhongming , Wang Limin , Liu Zhongyuan , Tian Yongjun
Published: February 2016

Black phosphorous (BP) is a unique layered p‐type semiconducting material. The successful use of BP nanosheets in field‐effect transistors fueled research on BP atomic layers that focuses on, e.g., the exploration of their optical and electronic properties, and promising applications in (opto)electronics. However, BP films are prone to degradation in ambient conditions, which prevents their commercial application. Here, a route to the application of BP films as an environmental stable nonvolatile resistive random access memory is presented. The BP films, which are prepared from exfoliated BP nanosheets in selected solvents, show solvent‐dependent degradation upon ambient exposure, inducing the formation of an amorphous top degraded layer (TDL). The TDL acts as an insulating barrier just below the Al electrode. This property that was only obtained by degradation, confers a bipolar resistive switching behavior with a high ON/OFF current ratio up to ~3 × 105 and excellent retention ability over 105 s to the flexible BP memory devices. The TDL also prevents propagation of degradation further into the film, ensuring excellent memory performance even after three month of ambient exposure.
Template‐Based Engineering of Carbon‐Doped Co3O4 Hollow Nanofibers as Anode Materials for Lithium‐Ion Batteries
Authors: Yan Chunshuang , Chen Gang , Zhou Xin , Sun Jingxue , Lv Chade
Published: February 2016

Co3O4 anode materials exhibit poor conductivity and a large volume change, rendering controlling of their nanostructure essential to optimize their lithium storage performance. Carbon‐doped Co3O4 hollow nanofibers (C‐doped Co3O4 HNFs), for the first time are synthesized using bifunctional polymeric nanofibers as template and carbon source. Compared with undoped Co3O4 HNFs and solid Co3O4 NFs, C‐doped Co3O4 HNFs feature a remarkably high specific capacity, excellent cycling stability, and superior rate capacity as anode materials for lithium‐ion batteries. The superior performance of C‐doped Co3O4 HNFs electrodes can be attributed to their structural features, which confer enhanced electron transportation and Li+ ion diffusion due to C‐doping, and tolerance for volume change due to the 1D hollow structure. Density functional theory calculations provide a good explanation of the observed enhanced conductivity in C‐doped Co3O4 HNFs.
Novel Strategy to Develop Exciplex Emitters for High‐Performance OLEDs by Employing Thermally Activated Delayed Fluorescence Materials
Authors: Liu Wei , Chen Jia‐Xiong , Zheng Cai‐Jun , Wang Kai , Chen Dong‐Yang , Li Fan , Dong Yu‐Ping , Lee Chun‐Sing , Ou Xue‐Mei , Zhang Xiao‐Hong
Published: February 2016

To develop high‐performance thermally activated delayed fluorescence (TADF) exciplex emitters, a novel strategy of introducing a single‐molecule TADF emitter as one of the constituting materials has been presented. Such a new type of exciplex TADF emitter will have two reverse intersystem crossing (RISC) routes on both the pristine TADF molecules and the exciplex emitters, benefiting the utilization of triplet excitons. Based on a newly designed and synthesized single‐molecule TADF emitter MAC, a highly efficient exciplex emitter MAC:PO‐T2T has been obtained. The device based on MAC:PO‐T2T with a weight ratio of 7:3 exhibits a low turn‐on voltage of 2.4 V, high maximum efficiency of 52.1 cd A−1 (current efficiency), 45.5 lm W−1 (power efficiency), and 17.8% (external quantum efficiency, EQE), as well as a high EQE of 12.3% at a luminance of 1000 cd m−2. The device shows the best performance among reported organic light‐emitting devices based on exciplex emitters. Such high‐efficiency and low‐efficiency roll‐off should be ascribed to the additional reverse intersystem crossing process on the MAC molecules, showing the advantages of the strategy described in this study.
Blood pressure and the capacity‐load model in 8‐year‐old children fromNepal: Testing the contributions of kidney size and intergenerational effects
Authors: Wells Jonathan C.K. , Devakumar Delan , Grijalva‐Eternod Carlos S. , Manandhar Dharma S. , Costello Anthony , Osrin David
Published: February 2016

Objectives

Growth patterns in early life are increasingly linked with subsequent cardio‐metabolic risk, but the underlying mechanisms require elucidation. We have developed a theoretical model of blood pressure, treating it as a function of homeostatic metabolic capacity, and antagonistic metabolic load. We sought to differentiate prenatal and postnatal components of metabolic capacity, and to identify intergenerational contributions to offspring capacity and load.

Methods

We followed up at 8 years a cohort of children originally recruited into a randomized trial of maternal micronutrient supplementation in pregnancy. Maternal anthropometry was measured at recruitment. Offspring anthropometry was measured at birth, 2 years and 8 years. Offspring blood pressure, kidney size, and body composition were measured at 8 years. Regression analysis was used to investigate potential associations of maternal phenotype, birth phenotype, and current body composition with kidney size and blood pressure.

Results

Blood pressure was positively associated with body fat, but negatively associated with birth weight and relative leg length. Kidney size was positively associated with birth weight but not with relative leg length. Adjusting for adiposity, blood pressure was independently negatively associated with birth weight, relative leg length, and kidney length. Maternal height and BMI predicted offspring size at birth and at 8 years, but not blood pressure.

Conclusions

Our data provide support for the capacity‐load model of blood pressure in Nepalese children. Fetal and postnatal growth and kidney dimensions all contribute to metabolic capacity. Maternal phenotype contributed to offspring capacity and load, but these associations did not propagate to blood pressure. Am. J. Hum. Biol. 28:555–565, 2016. © 2016 The Authors American Journal of Human Biology Published by Wiley Periodicals, Inc
Palladium‐Catalyzed C−H Arylation of α,β‐Unsaturated Imines: Catalyst‐Controlled Synthesis of Enamine and Allylic Amine Derivatives
Authors: Li Minyan , González‐Esguevillas María , Berritt Simon , Yang Xiaodong , Bellomo Ana , Walsh Patrick J.
Published: February 2016

A unique chemo‐ and regioselective α‐ and γ‐arylation of palladium azapentadienyl intermediates is presented. Two distinct catalysts and sets of conditions successfully controlled the regioselectivity of the arylation. These methods provide the first umpolung C−H functionalization of azapentadienyl palladium intermediates and enable the divergent synthesis of allylic amine and enamine derivatives, which are of significant interest in the pharmaceutical industry.
Compatibilized the thermosetting blend of epoxy and redistributed low molecular weight poly(phenylene oxide) with triallylisocyanurate
Authors: Chen Wenjing , Yang Hongli , Zou Huawei , Liu Pengbo
Published: February 2016

Vinyl‐containing low molecular weight PPO (R‐PPO) was prepared by redistribution reaction between commercially available PPO and maleic anhydride (MAH) and used to modify epoxy resin (EP). TAIC was furthermore used as the compatibilizer of EP/R‐PPO system in this study. The curing reaction kinetics, compatibility of the components, morphology, dielectric properties and impact toughness of EP/R‐PPO/TAIC systems were investigated. The experimental results showed that the cured EP/R‐PPO (80/20) system had two phase morphology, the R‐PPO particles of about 1 µm were evenly dispersed in continuous epoxy phase. After addition of TAIC, the EP/R‐PPO/TAIC systems were transferred to single phase. The glass transition temperature of cured EP/R‐PPO/TAIC (80/20/10) system was 150.2 °C. With the increase of TAIC content, the dielectric constant (Dk) and dissipation factor (Df) of cured EP/R‐PPO/TAIC systems were both reduced. The dielectric constant and dissipation factor at 1MHz of cured EP/R‐PPO/TAIC (80/20/10) system was 2.72 and 0.006, respectively. Compared with those of cured EP/R‐PPO (80/20) system (Dk = 2.82 and Df = 0.0078 at 1MHz), they decreased by 3.6% and 23.1%, respectively. With the increase of TAIC content, the impact strength of cured EP/R‐PPO (80/20) system increased and reached to a maximum value (2.41 kJ/m2) when TAIC content was 10 phr, which was improved by 23% compared with that of cured EP/R‐PPO (80/20) system (1.96 kJ/m2). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43293.
Effect of the injection moulding processing conditions on the development of pea protein‐based bioplastics
Authors: Perez-Puyana V. , Felix M. , Romero A. , Guerrero A.
Published: February 2016

Bioplastic materials from renewable polymers, like proteins, constitute a highly interesting field for important industrial applications such as packaging, agriculture, etc., in which thermo‐mechanical techniques are increasingly being used. Pea protein‐based bioplastics can be made through a mixing process followed by an injection moulding. The objective of this study was to investigate the influence of different injection parameters (moulding time and injection pressure) on the properties exhibited by the final bioplastics obtained. A dynamic mechanical analysis and tensile strength measurements were performed, along with water absorption capacity and transparency tests. The results indicated that the major differences between bioplastics obtained at different moulding times are in transparency and in the Young's Moduli, exhibiting lower values as moulding time increases. On the other hand, modifying the injection pressure lead to more consistent bioplastics which differed mainly in the elastic component (E′ profiles) and in the strain at break. Furthermore, the water uptake was more than 100% in almost all the different bioplastics processed because of its hydrophilic character, so they could be considered as potential sources for absorbent material. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43306.
Preparation of a porous, magnetic, quaternary chitosan salt by preadsorption and desorption for azo dye adsorption from water
Authors: Zhang Conglu , Zhu Lei , Li Wei , Zheng Xin
Published: February 2016

A porous magnetic quaternary chitosan salt (pre‐CS/EPTAC/Fe3O4) was successfully prepared via a kind of novel method of preadsorption and desorption. The physicochemical properties of pre‐CS/EPTAC/Fe3O4 were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and vibrating sample magnetometry. The adsorption of pre‐CS/EPTAC/Fe3O4 for methyl orange (MO) showed much higher dye uptakes compared with Npre‐CS/EPTAC/Fe3O4 without the preadsorption and desorption of MO, and the maximum adsorption capability for MO was 486.1 mg/g. Adsorption isotherms and adsorption kinetics were well fitted by the Freundlich isotherm model and the pseudo‐second order model, respectively. Thermodynamic parameters, such as the standard free energy change, enthalpy change, and entropy change, were also calculated; this indicated that the adsorption was spontaneous and exothermic. The introduction of MO preadsorption and desorption into the process of preparation improved not only the adsorption of MO but also the adsorption of acid red 1 and orange G. Furthermore, pre‐CS/EPTAC/Fe3O4 particles could be easily regenerated and remained almost constant (98.5%) for six cycles of adsorption and desorption. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43448
Kommentierung der neuen DIN 4093 “Bemessung von verfestigten Bodenkörpern”
Authors: Vogt Norbert , Borchert Kurt Michael , Beckhaus Karsten , Breitsprecher Georg , Dausch Gebhard , Dietz Klaus , Kayser Jan , Pandrea Paul , Schulze Bertram , Schwarz Helmut , Tausch Norbert
Published: February 2016

Die neue DIN 4093 regelt wichtige Punkte zu Entwurf und Bemessung von verfestigten Bodenkörpern, die durch Düsenstrahl‐, Deep‐Mixing‐ oder Injektions‐Verfahren hergestellt werden. Anders als in der alten Injektionsnorm werden Themen der Ausführung, die europäisch einheitlich behandelt werden, hierin nicht erfasst. Der vorliegende Beitrag erläutert wichtige Regelungen dieser vollständig neu erstellten Norm sowie einige Besonderheiten, die vor der Anwendung der genannten Verfahren zu beachten sind.

Comment on the new DIN 4093 – Design of strengthened soil

The new DIN 4093 contains important rules for the design of strengthened soil installed by jet grouting, soil mixing or grouting. Unlike in the old German grouting standard code, aspects of execution, which are content of European standards, are no longer included. This publication explains essential requirements and recommendations of this completely new standard code as well as some particularities which have to be obeyed prior to the application of the named technologies.
An integrated practical implementation of continuous aqueous two‐phase systems for the recovery of human IgG: From the microdevice to a multistage bench‐scale mixer‐settler device
Authors: Espitia‐Saloma Edith , Vâzquez‐Villegas Patricia , Rito‐Palomares Marco , Aguilar Oscar
Published: February 2016

Aqueous two‐phase systems (ATPS) are a liquid‐liquid extraction technology with clear process benefits; however, its lack of industrial embracement is still a challenge to overcome. Antibodies are a potential product to be recovered by ATPS in a commercial context. The objective of this work is to present a more integral approach of the different isolated strategies that have arisen in order to enable a practical, generic implementation of ATPS, using human immunoglobulin G (IgG) as experimental model. A microfluidic device is used for ATPS parameters preselection for product recovery. ATPS were continuously operated in a mixer‐settler device in one stage, multistage and multistage with recirculation configuration. Single‐stage pure IgG extraction with a polyethylene glycol (PEG) 3350‐phophates ATPS within continuous operation allowed a 65% recovery. Further implementation of a multistage platform promoted a higher particle partitioning reaching a 90% recovery. The processing of IgG from a cell supernatant culture harvest in a multistage system with top phase recirculation resulted in 78% IgG recovery in bottom phase. This work conjugates three not widely spread methodologies for ATPS: microfluidics, continuous and multistage operation.
Microstructural white‐matter abnormalities and their relationship with cognitive dysfunction in obsessive–compulsive disorder
Authors: Magioncalda Paola , Martino Matteo , Ely Benjamin A. , Inglese Matilde , Stern Emily R.
Published: February 2016

Background

In recent years, diffusion tensor imaging (DTI) studies have detected subtle microstructural abnormalities of white matter (WM) in obsessive–compulsive disorder (OCD). However, findings have been inconsistent, and it is unclear whether WM abnormalities are related to cognitive processes. The aim of this study was to explore the relationship of WM alterations with cognitive variables in OCD in order to investigate the structural correlates of behaviorally relevant features of the disorder.

Methods

We compared DTI‐derived fractional anisotropy (FA), mean diffusivity (MD), and radial diffusivity (RD) measures between OCD patients (n = 16) and healthy controls (n = 18) using a whole‐brain tract‐based spatial statistics (TBSS) approach. We also explored the correlations of WM alterations with clinical and cognitive variables.

Results

Patients with OCD demonstrated increases in MD in the bilateral posterior corona radiata; left anterior corona radiata; bilateral superior longitudinal fasciculus; genu, body, and splenium of the corpus callosum; and left posterior limb of the internal capsule. An increase in RD values was also found in some of the same tracts (right posterior corona radiata, right superior longitudinal fasciculus, left anterior corona radiata, and corpus callosum). Furthermore, increased MD value in the internal capsule was correlated with the percentage of errors made during a target detection task, which was greater in the OCD group overall.

Conclusions

These findings indicate that OCD patients show greater diffusivity in several white‐matter regions. The correlation between cognitive performance and diffusivity in the internal capsule suggests that microstructural WM alternations may have functional consequences for the disorder.
Ni Nanoparticles Stabilized by Poly(Ionic Liquids) as Chemoselective and Magnetically Recoverable Catalysts for Transfer Hydrogenation Reactions of Carbonyl Compounds
Authors: Vijayakrishna Kari , Charan K. T. Prabhu , Manojkumar Kasina , Venkatesh Sadhana , Pothanagandhi Nellepalli , Sivaramakrishna Akella , Mayuri Pinapeddavari , Kumar Annamalai Senthil , Sreedhar B.
Published: February 2016

Imidazolium‐based poly(ionic liquids) with hydroxide as the counter anion were employed to prepare stable aqueous dispersion of Ni nanoparticles. The synthesized poly(ionic liquid) stabilized Ni nanoparticles (PIL‐Ni‐NPs) were characterized by thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), powder XRD, TEM, Brunauer–Emmett–Teller (BET) surface area measurements, X‐ray photoelectron spectroscopy (XPS), EPR, and UV/Vis spectroscopy. The PIL‐Ni‐NPs possess good catalytic activity towards transfer hydrogenation (TH) reactions of carbonyl compounds to their alcohol derivatives, in isopropanol at 80 °C in the absence of any additional base. This catalyst system chemoselectively reduces only the carbonyl group of α,β unsaturated carbonyl compounds. The magnetically separable PIL‐Ni‐NPs were recycled and reused for further TH reactions.
Adsorption Equilibria of Dimethyl Carbonate and Ethyl Methyl Carbonate onto Activated Carbon
Authors: Stehmann Friederike , Prziwara Paul , Bradtmöller Christian , Schoenitz Martin , Scholl Stephan
Published: February 2016

Increasing usage of lithium‐ion batteries requires new recycling strategies. Dimethyl carbonate (DMC) and ethyl methyl carbonate (EMC) represent about 50 % of the electrolyte and need to be captured from recycling exhaust gas. This study identifies adsorption as an advantageous method. Single component isotherms of DMC and EMC are presented applying the model of Tóth. Model parameters are used to calculate binary adsorption isotherms with the ideal adsorbed solution theory. Comparison with experimental data shows good agreement in respect to selectivity, temperature dependence and overall gas loading.
3D DEM‐CFD Simulation of the Formation of a Fixed Bed of Activated Carbon Grains, Air and Toluene Permeation and Toluene Adsorption
Authors: Schmidt Kilian , Ripperger Siegfried , Antonyuk Sergiy
Published: February 2016

Adsorption is an indispensable technology in many industrial processes. In order to enhance the understanding of the process and to optimize its application, simulation is a useful tool. An approach to simulate adsorption of toluene from air in a fixed bed of activated carbon grains is exemplified. A 3D model of the fixed bed is generated by the discrete element method. Computational fluid dynamics simulations are carried out by the Lattice‐Boltzmann method. Numerical parameters are calibrated by matching single grain loading curves to experimental data.
Comparison of Coronary Artery Disease Consortium 1 and 2 Scores and Duke Clinical Score to Predict Obstructive Coronary Disease by Invasive Coronary Angiography
Authors: Almeida João , Fonseca Paulo , Dias Tiago , Ladeiras‐Lopes Ricardo , Bettencourt Nuno , Ribeiro José , Gama Vasco
Published: February 2016

Background

The first step in evaluating a patient with suspected stable coronary artery disease (CAD) is the determination of the pretest probability. The European Society of Cardiology guidelines recommend the use of the CAD Consortium 1 score (CAD1), which contrary to CAD Consortium 2 (CAD2) score and Duke Clinical Score (DCS), does not include modifiable cardiovascular risk factors.

Hypothesis

Using scores that include modifiable risk factors (DCS and CAD2) enhances prediction of CAD.

Methods

We retrospectively included all patients referred to invasive coronary angiography for suspected CAD from January/2008–December/2012 (N = 2234). Pretest probability was calculated using 3 models (CAD1, DCS, and CAD2), and they were compared using the net reclassification improvement.

Results

Mean patient age was 63.7 years, 67.5% were male, and the majority (66.9%) had typical angina. Coronary artery disease was diagnosed in 58.5%, and the area under the curve was 0.685 for DCS, 0.664 for CAD1, and 0.683 for CAD2, with a statistically significant difference between CAD1 and the others (P < 0.001). The net reclassification improvement was 20% for DCS, related to adequate reclassification of 32% of patients with CAD to a higher risk category, and 5% for CAD2, at the cost of adequate reclassification of 34% of patients without CAD to a lower risk category.

Conclusions

Prediction of CAD using scores that include modifiable cardiovascular risk factors seems to improve accuracy. Our results suggest that, in high‐prevalence populations, DCS may better identify patients at higher risk and CAD2 those at lower risk for CAD.
The nucleus is a conserved mechanosensation and mechanoresponse organelle
Authors: Navarro Alexandra P. , Collins Mary Ann , Folker Eric S.
Published: February 2016

Cells in vivo exist in a dynamic environment where they experience variable mechanical influences. The precise mechanical environment influences cell‐cell interactions, cell‐extracellular matrix interactions, and in‐turn, cell morphology and cell function. Therefore, the ability of each cell to constantly and rapidly alter their behavior in response to variations in their mechanical environment is essential for cell viability, development, and function. Mechanotransduction, the process by which mechanical force is translated into a biochemical signal to activate downstream cellular responses, is thus crucial to cell function during development and homeostasis. Although much research has focused on how protein complexes at the cell cortex respond to mechanical stress to initiate mechanotransduction, the nucleus has emerged as crucial to the ability of the cell to perceive and respond to changes in its mechanical environment. This additional method for mechanosensing allows for direct transmission of force through the cytoskeleton to the nucleus, which can increase the speed at which a cell changes its transcriptional profile. This review discusses recent work demonstrating the importance of the nucleus in mediating the cellular response to internal and external force, establishing the nucleus as an important mechanosensing organelle. © 2016 Wiley Periodicals, Inc.
Word morph and topological structures: A graph generating algorithm
Authors: Klüver Jürgen , Schmidt Jörn , Klüver Christina
Published: February 2016

An algorithm of generating graph structures for the ordering of datasets is proposed. It operates with the key concept of “sphere neighborhood” and generates the graph structured ordering of datasets, provided the elements of such sets can be related by some similarity relation. The algorithm always allows determining the shortest path between two nodes in a constructive way. It is demonstrated by an application to the famous Word Morph game and in addition to the ordering of logfiles with respect to the detection of errors. Therefore, the algorithm can be very useful for the dealing with Big Data problems. © 2016 Wiley Periodicals, Inc. Complexity 21: 426–436, 2016
Relative effectiveness of azithromycin in killing intracellular Porphyromonas gingivalis
Authors: Lai Pin‐Chuang , Walters John D.
Published: February 2016

Invasive infections by Porphyromonas gingivalis are associated with persistent periodontal attachment loss and can be difficult to eliminate by scaling and root planing. Azithromycin (AZM) inhibits P. gingivalis and is actively accumulated by most human cells. We used an in vitro infection model to compare the effectiveness of AZM in killing intracellular P. gingivalis to the combined regimen of amoxicillin (AMX) and metronidazole (MET). Transport of [3H]‐AZM by human gingival fibroblasts was characterized. Monolayers of Smulow–Glickman gingival epithelial cells or gingival fibroblasts were infected with P. gingivalis (strain 33277 or W83). After extracellular bacteria were eliminated with teicoplanin, infected cells were treated with therapeutic concentrations of AZM, AMX, or AMX + MET. Viable intracellular bacteria were released by cell lysis and plated on blood agar for enumeration. Antimicrobial activity against planktonic P. gingivalis was also evaluated. While survival of intraepithelial P. gingivalis 33277 was not significantly different after treatment with the three regimens, survival in infected fibroblasts was significantly lower after AZM treatment (65.9 ± 5.5%) compared with AMX (92.2 ± 3.5%) or AMX + MET (79.8 ± 5.2%, P < 0.01). Carnitine, a competitive inhibitor of AZM transport, reduced killing by AZM by ~55% (P < 0.05). Survival of intrafibroblast P. gingivalis W83 was also significantly lower after AZM treatment compared with the other regimens (P < 0.05). At therapeutic concentrations, AZM was significantly more active against intracellular P. gingivalis than against planktonic P. gingivalis (P < 0.0083). Gingival epithelial cells and fibroblasts possess a transport system that accumulates AZM and enhances elimination of intracellular P. gingivalis. Compared with the combination of AMX and MET, AZM was equally effective against intraepithelial P. gingivalis 33277 and significantly more effective against both strains of P. gingivalis from infected gingival fibroblasts. The results suggest that AZM could be a reasonable alternative to the regimen of AMX and MET for periodontal patients who should not take these agents due to known side effects or compliance issues.