bluuebunny/crossref_metadata_2025 huggingface dataset:
Hybrid simulations of coupled Farley‐Buneman/gradient drift instabilities in the equatorial E region ionosphere
Authors: Young Matthew A. , Oppenheim Meers M. , Dimant Yakov S.
Published: May 2017

Plasma irregularities in the equatorial E region ionosphere are classified as Type I or Type II, based on coherent radar spectra. Type I irregularities are attributed to the Farley‐Buneman instability and Type II to the gradient drift instability that cascades to meter‐scale irregularities detected by radars. This work presents the first kinetic simulations of coupled Farley‐Buneman and gradient drift turbulence in the equatorial E region ionosphere for a range of zeroth‐order vertical electric fields, using a new approach to solving the electrostatic potential equation. The simulation models a collisional quasi‐neutral plasma with a warm, inertialess electron fluid and a distribution of NO+ ions. A 512 m wave with a maximum/minimum of ±0.25 of the background density perturbs the plasma. The density wave creates an electrostatic field that adds to the zeroth‐order vertical and ambipolar fields, and drives Farley‐Buneman turbulence even when these fields are below the instability threshold. Wave power spectra show that Type II irregularities develop in all simulation runs and that Type I irregularities with wavelengths of a few meters develop in the trough of the background wave in addition to Type II irregularities as the zeroth‐order electric field magnitude increases. Linear fluid theory predicts the growth of Type II irregularities reasonably well, but it does not fully capture the simultaneous growth of Type I irregularities in the region of peak total electric field. The growth of localized Type I irregularities represents a parametric instability in which the electric field of the large‐scale background wave drives pure Farley‐Buneman turbulence. These results help explain observations of meter‐scale irregularities advected by kilometer‐scale waves.
Precise relative earthquake depth determination using array processing techniques
Authors: Florez M. A. , Prieto G. A.
Published: May 2017

Precise determination of hypocentral depth remains one of the most relevant problems in earthquake seismology. It is well known that using depth phases allows for significant improvement in event depth determination; however, routinely and systematically picking such phases, for teleseismic or regional arrivals, is problematic due to poor signal‐to‐noise ratios around the pP and sP phases. To overcome this limitation, we have taken advantage of the additional information carried by seismic arrays. We use velocity spectral analysis to precisely measure pP‐P times. The individual estimates obtained at different subarrays, for all pairs of earthquakes, are combined using a double‐difference algorithm, in order to precisely map seismicity in regions where it is tightly clustered. We illustrate this method by relocating intermediate‐depth earthquakes in the Nazca subducting plate, beneath northern Chile, where we confirm the existence of a narrowly spaced double seismic zone, previously imaged using a local dedicated deployment. As a second example we relocate the aftershock sequence of the 2014 Mw 7.9 intermediate depth, Rat Islands earthquake, and provide evidence of a subvertical fault plane for the main shock. Finally, we show that the resulting relative depth errors are typically smaller than 2 km.
Deformation style and controlling geodynamic processes at the eastern Guadalquivir foreland basin (Southern Spain)
Authors: Marín‐Lechado C. , Pedrera A. , Peláez J. A. , Ruiz‐Constán A. , González‐Ramón A. , Henares J.
Published: May 2017

The tectonic structure of the Guadalquivir foreland basin becomes complex eastward evolving from a single depocenter to a compartmented basin. The deformation pattern within the eastern Guadalquivir foreland basin has been characterized by combining seismic reflection profiles, boreholes, and structural field data to output a 3‐D model. High‐dipping NNE‐SSW to NE‐SW trending normal and reverse fault arrays deform the Variscan basement of the basin. These faults generally affect Tortonian sediments, which show syntectonic features sealed by the latest Miocene units. Curved and S‐shaped fault traces are abundant and caused by the linkage of nearby fault segments during lateral fault propagation. Preexisting faults were reactivated either as normal or reverse faults depending on their position within the foreland. At Tortonian time, reverse faults deformed the basin forebulge, while normal faults predominated within the backbulge. Along‐strike variation of the Betic foreland basin geometry is supported by an increasing mechanical coupling of the two plates (Alborán Domain and Variscan basement) toward the eastern part of the cordillera. Thus, subduction would have progressed in the western Betics, while it would have failed in the eastern one. There, the initially subducted Iberian paleomargin (Nevado‐Filábride Complex) was incorporated into the upper plate promoting the transmission of collision‐related compressional stresses into the foreland since the middle Miocene. Nowadays, compression is still active and produces low‐magnitude earthquakes likely linked to NNE‐SSW to NE‐SW preexiting faults reactivated with reverse oblique‐slip kinematics. Seismicity is mostly concentrated around fault tips that are frequently curved in overstepping zones.
Bioprinted Osteogenic and Vasculogenic Patterns for Engineering 3D Bone Tissue
Authors: Byambaa Batzaya , Annabi Nasim , Yue Kan , Trujillo‐de Santiago Grissel , Alvarez Mario Moisés , Jia Weitao , Kazemzadeh‐Narbat Mehdi , Shin Su Ryon , Tamayol Ali , Khademhosseini Ali
Published: May 2017

Fabricating 3D large‐scale bone tissue constructs with functional vasculature has been a particular challenge in engineering tissues suitable for repairing large bone defects. To address this challenge, an extrusion‐based direct‐writing bioprinting strategy is utilized to fabricate microstructured bone‐like tissue constructs containing a perfusable vascular lumen. The bioprinted constructs are used as biomimetic in vitro matrices to co‐culture human umbilical vein endothelial cells and bone marrow derived human mesenchymal stem cells in a naturally derived hydrogel. To form the perfusable blood vessel inside the bioprinted construct, a central cylinder with 5% gelatin methacryloyl (GelMA) hydrogel at low methacryloyl substitution (GelMALOW ) was printed. We also develop cell‐laden cylinder elements made of GelMA hydrogel loaded with silicate nanoplatelets to induce osteogenesis, and synthesized hydrogel formulations with chemically conjugated vascular endothelial growth factor to promote vascular spreading. It was found that the engineered construct is able to support cell survival and proliferation during maturation in vitro. Additionally, the whole construct demonstrates high structural stability during the in vitro culture for 21 days. This method enables the local control of physical and chemical microniches and the establishment of gradients in the bioprinted constructs.
Tuning of the Optical, Electronic, and Magnetic Properties of Boron Nitride Nanosheets with Oxygen Doping and Functionalization
Authors: Weng Qunhong , Kvashnin Dmitry G. , Wang Xi , Cretu Ovidiu , Yang Yijun , Zhou Min , Zhang Chao , Tang Dai‐Ming , Sorokin Pavel B. , Bando Yoshio , Golberg Dmitri
Published: May 2017

Engineering of the optical, electronic, and magnetic properties of hexagonal boron nitride (h‐BN) nanomaterials via oxygen doping and functionalization has been envisaged in theory. However, it is still unclear as to what extent these properties can be altered using such methodology because of the lack of significant experimental progress and systematic theoretical investigations. Therefore, here, comprehensive theoretical predictions verified by solid experimental confirmations are provided, which unambiguously answer this long‐standing question. Narrowing of the optical bandgap in h‐BN nanosheets (from ≈5.5 eV down to 2.1 eV) and the appearance of paramagnetism and photoluminescence (of both Stokes and anti‐Stokes types) in them after oxygen doping and functionalization are discussed. These results are highly valuable for further advances in semiconducting nanoscale electronics, optoelectronics, and spintronics.
Bioinspired Ultratough Hydrogel with Fast Recovery, Self‐Healing, Injectability and Cytocompatibility
Authors: Azevedo Sara , Costa Ana M. S. , Andersen Amanda , Choi Insung S. , Birkedal Henrik , Mano João F.
Published: May 2017

Inspired by the mussel byssus adhesiveness, a highly hydrated polymeric structure is designed to combine, for the first time, a set of interesting features for load‐bearing purposes. These characteristics include: i) a compressive strength and stiffness in the MPa range, ii) toughness and the ability to recover it upon successive cyclic loading, iii) the ability to quickly self‐heal upon rupture, iv) the possibility of administration through minimally invasive techniques, such as by injection, v) the swelling ratio being adjusted to space‐filling applications, and vi) cytocompatibility. Owing to these characteristics and the mild conditions employed, the encapsulation of very unstable and sensitive cargoes is possible, highlighting their potential to researchers in the biomedical field for the repair of load‐bearing soft tissues, or to be used as an encapsulation platform for a variety of biological applications such as disease models for drug screening and therapies in a more realistic mechanical environment. Moreover, given the simplicity of this methodology and the enhanced mechanical performance, this strategy can be expanded to applications in other fields, such as agriculture and electronics. As such, it is anticipated that the proposed strategy will constitute a new, versatile, and cost‐effective tool to produce engineered polymeric structures for both science and technology.
A Mixed‐Metal Oxides/Graphitic Carbon Nitride: High Visible Light Photocatalytic Activity for Efficient Mineralization of Rhodamine B
Authors: Huy Bui The , Thao Chu Thi Bich , Dao Van‐Duong , Phuong Nguyen Thi Kim , Lee Yong‐Ill
Published: May 2017

Novel photocatalysts in the form of zinc oxide‐zinc bismuth oxide (mixed‐metal oxide [MMO]) and graphitic carbon nitride (CN) hybrid composites are developed via a co‐precipitation method followed by calcination at 520 °C. The as‐prepared MMO‐CN hybrid composites are evaluated on the basis of their photocatalytic activities for Rhodamine B (RhB) in aqueous solutions under visible light irradiation. The strong electronic coupling between two components within the MMO‐CN heterostructure, which suppresses the photogenerated recombination of electrons and holes to a remarkable extent, is revealed. The prepared composites exhibit an excellent photocatalytic activity, leading to more than 95% of RhB degradation at an initial concentration of 50 mg L−1 using 0.5 g catalyst per liter in 90 min, along with 25 min of the RhB half‐life time. The excellent photocatalytic mineralization of MMO‐4.0CN by visible light irradiation can be attributed to the synergic effects for high and charge transfer between MMO and CN as well as efficient separation of photogenerated electrons and holes. The species most responsible for photodegradation is holes (h
+) with moderate and minor contributions by the superoxide anion and hydroxyl radicals, respectively. These results attest to a green, low cost, and high efficiency photocatalyst for environmental remediation.
Combining Electrode Flexibility and Wave‐Like Device Architecture for Highly Flexible Li‐Ion Batteries
Authors: Meng Qinghai , Wu Haiping , Mao Lijuan , Yuan Hongxin , Ahmad Aziz , Wei Zhixiang
Published: May 2017

Highly flexible Li‐ion batteries are potential materials for futuristic smart wearable devices. However, previously reported flexible batteries depend mainly on electrode flexibility. In this study, a highly flexible Li‐ion battery is developed by combining electrode flexibility and wave‐like device architecture. A Cu‐deposited conductive nonwoven cloth and a carbon nanotube film are used as current collectors to improve the flexibility of electrodes and maintain their good conductivity. The wave‐like structure can release the tensile and compressive strains during bending and prevent the detachment of various layers. In this manner, the battery exhibits high flexibility and good electrochemical performance and presents 92% capacity retention after 2000 times of bending. The open circuit voltage of the battery is also retained after 10 000 times of bending. The as‐prepared flexible Li‐ion battery is integrated with a night running armband. Thus, the proposed battery can be a potential component for wearable electronics.
3D‐Printed Disposable Wireless Sensors with Integrated Microelectronics for Large Area Environmental Monitoring
Authors: Farooqui Muhammad Fahad , Karimi Muhammad Akram , Salama Khaled Nabil , Shamim Atif
Published: May 2017

Large area environmental monitoring can play a crucial role in dealing with crisis situations. However, it is challenging as implementing a fixed sensor network infrastructure over large remote area is economically unfeasible. This work proposes disposable, compact, dispersible 3D‐printed wireless sensor nodes with integrated microelectronics which can be dispersed in the environment and work in conjunction with few fixed nodes for large area monitoring applications. As a proof of concept, the wireless sensing of temperature, humidity, and H2S levels are shown which are important for two critical environmental conditions namely forest fires and industrial leaks. These inkjet‐printed sensors and an antenna are realized on the walls of a 3D‐printed cubic package which encloses the microelectronics developed on a 3D‐printed circuit board. Hence, 3D printing and inkjet printing are uniquely combined in order to realize a low‐cost, fully integrated wireless sensor node.
Modeling of CO2 equilibrium solubility in a novel 1‐Diethylamino‐2‐Propanol Solvent
Authors: Liu Helei , Xiao Min , Luo Xiao , Gao Hongxia , Idem Raphael , Tontiwachwuthikul Paitoon , Liang Zhiwu
Published: May 2017

In this work, the equilibrium solubility of CO2 in a 1‐diethylamino‐2‐propanol (1DEA2P) solution was determined as a function of 1DEA2P concentration (over the range of 1–2 M), temperature (in the range of 298–333 K), and CO2 partial pressure (in the range of 8–101 kPa). These experimental results were used to fit the present correlation for K2 (Kent‐Eisenberg model, Austgen model, and Li‐Shen model). It was found that all of the models could represent the CO2 equilibrium solubility in 1DEA2P solution with ADDs for Kent‐Eisenberg model, Austgen model, and Li‐Shen model of 6.3, 7.3, and 12.2%, respectively. A new K2 correlation model, the Liu‐Helei model, was also developed to predict the CO2 equilibrium solubility in 1DEA2P solution with an excellent ADD of 3.4%. In addition, the heat of absorption of CO2 in 1DEA2P solution estimated by using the Gibbs‐Helmholtz equation was found to be −45.7 ± 3.7 kJ/mol. Information and guidelines about effectively using data for screened solvents is also provided based on the three absorption parameters: CO2 equilibrium solubility, second order reaction constant (k2), and CO2 absorption heat. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4465–4475, 2017
Time‐resolved ultrasonic spectroscopy for bubbles
Authors: Leroy Valentin , Strybulevych Anatoliy , Norisuye Tomohisa
Published: May 2017

We show that ultrasound can provide time‐resolved measurements of the size distribution and the concentration of bubbles in a liquid. The potential of the technique is demonstrated by following disappearance of bubbles having an average radius of 20 μm with a 10 ms time resolution. We show that our technique can detect small concentrations of bubbles, with a large spectrum of accessible bubble radii (from 80 nm to 40 μm for a gas volume fraction of
), and with a sub‐millisecond time resolution. This new technique could be a valuable tool for investigating rapid processes such as nucleation or dissolution of bubbles. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4666–4672, 2017
Kinetically Controlled Layer‐by‐Layer Stacking of Metal Oxide 2D Nanosheets
Authors: Lim Joohyun , Jin Xiaoyan , Jo Yun Kyung , Lee Seul , Hwang Seong‐Ju
Published: May 2017

An efficient chemical way to finely control the layer‐by‐layer stacking of inorganic nanosheets (NS) is developed by tuning the type and composition of intercalant ion, and the reaction temperature for restacking process. The finely controlled stacking of NS relies on a kinetic control of the self‐assembly of NS in the presence of coordinating organic cations. A critical role of organic cations in this assembly highlights the importance of the appropriate activation energy. Of prime importance is that a fine‐control of the interstratification of 2D NS is highly effective not only in tailoring its pore structure but also in enhancing its electrode activity. The present study clearly demonstrates that the kinetically controlled restacking of NS provides a facile and powerful method to tailor their stacking number and functionality.
Identifikation sekundärer Bindestellen auf DC‐SIGN mithilfe eines Fragment‐Screenings
Authors: Aretz Jonas , Baukmann Hannes , Shanina Elena , Hanske Jonas , Wawrzinek Robert , Zapol'skii Viktor A. , Seeberger Peter H. , Kaufmann Dieter E. , Rademacher Christoph
Published: May 2017

Der Oberflächenrezeptor DC‐SIGN ermöglicht die Aufnahme von Krankheitserregern wie HIV, Ebolavirus oder Mycobacterium tuberculosis. Daher gab es zahlreiche Versuche, Inhibitoren gegen die Bindung dieses Rezeptors an Kohlenhydratstrukturen dieser Pathogene zu entwickeln. Wegen der hydrophilen und wenig markanten Glykan‐Bindestelle kennt man nur wenige Wirkstoff‐ähnliche Liganden für DC‐SIGN. Parallele Fragment‐Screenings mit SPR‐Spektroskopie und einem Reporter Displacement Assay ergänzen vorherige Screenings mit 19F‐NMR‐Spektroskopie und chemischen Mikroarrays. Die Validierung aktiver Substanzen mit SPR‐ und 1H‐15N‐HSQC‐NMR‐Spektroskopie zeigte, dass kein Fragment in die primäre Kohlenhydrattasche bindet, dafür jedoch fünf sekundäre Bindestellen vorhanden sind, die mit Wirkstoff‐ähnlichen Molekülen interagieren können. Mithilfe der Schlüsselinteraktionen der hier gezeigten Fragmente können diese Regionen gezielt erkundet und zukünftige Ansätze zur Entwicklung von DC‐SIGN‐Inhibitoren beschleunigt werden.
An Aggregating Amphiphilic Squaraine: A Light‐up Probe That Discriminates Parallel G‐Quadruplexes
Authors: Grande Vincenzo , Doria Filippo , Freccero Mauro , Würthner Frank
Published: May 2017

G‐quadruplexes (G4s) are peculiar DNA or RNA tertiary structures that are involved in the regulation of many biological events within mammalian cells, bacteria, and viruses. Although their role as versatile therapeutic targets has been emphasized for 35 years, G4 selectivity over ubiquitous double‐stranded DNA/RNA, as well as G4 differentiation by small molecules, still remains challenging. Here, a new amphiphilic dicyanovinyl‐substituted squaraine, SQgl, is reported to act as an NIR fluorescent light‐up probe discriminating an extensive panel of parallel G4s while it is non‐fluorescent in the aggregated state. The squaraine can form an unconventional sandwich π‐complex binding two quadruplexes, which leads to a strongly fluorescent (ΦF=0.61) supramolecular architecture. SQgl is highly selective against non‐quadruplex and non‐parallel G4 sequences without altering their topology, as desired for applications in selective in vivo high‐resolution imaging and theranostics.
Aufklärung der Rolle von CeO2‐Nanopartikel‐Auflösung bei der Aufnahme in die Pflanze mithilfe intelligenter Radiomarkierung
Authors: Schymura Stefan , Fricke Thomas , Hildebrand Heike , Franke Karsten
Published: May 2017

Die Identifizierung der Hauptaufnahmepfade von technischen Nanopartikeln in Pflanzen ist ein wichtiger Faktor bei der Einschätzung ihres Verbleibs in der Umwelt und der damit verbundenen Risiken. Durch den Einsatz unterschiedlicher Radiomarkierungsmethoden gelang es, eine hauptsächlich partikulär stattfindende Aufnahme von CeO2‐Nanopartikeln zu zeigen, im Unterschied zu einer Aufnahme in Form von ionischem Cer.
Enzymatic Engineering of Live Bacterial Cell Surfaces Using Butelase 1
Authors: Bi Xiaobao , Yin Juan , Nguyen Giang K. T. , Rao Chang , Halim Nurashikin Bte Abdul , Hemu Xinya , Tam James P. , Liu Chuan‐Fa
Published: May 2017

Butelase‐mediated ligation (BML) can be used to modify live bacterial cell surfaces with diverse cargo molecules. Surface‐displayed butelase recognition motif NHV was first introduced at the C‐terminal end of the anchoring protein OmpA on E. coli cells. This then served as a handle of BML for the functionalization of E. coli cell surfaces with fluorescein and biotin tags, a tumor‐associated monoglycosylated peptide, and mCherry protein. The cell‐surface ligation reaction was achieved at low concentrations of butelase and the labeling substrates. Furthermore, the fluorescein‐labeled bacterial cells were used to show the interactions with cultured HeLa cells and with macrophages in live transgenic zebrafish, capturing the latter's powerful phagocytic effect in action. Together these results highlight the usefulness of butelase 1 in live bacterial cell surface engineering for novel applications.
The Interstitial Carbon of the Nitrogenase FeMo Cofactor is Far Better Stabilized than Previously Assumed
Authors: Grunenberg Jörg
Published: May 2017

The first quantum‐mechanical calculations of all relevant potential constants in both the iron‐molybdenum cofactor and the iron‐vanadium cofactor of nitrogenase suggest that the carbide is bound to the center of the enzyme much more strongly than hitherto assumed. Previous studies seemed to indicate a dummy function of the interstitial carbon, with a weak force constant (ca. 0.32 N cm−1). Our new investigations confirm a different picture: the central carbon atom binds the iron‐sulfur cluster through six covalent C−Fe bonds. With a potential constant of more than 1.3 N cm−1, the interstitial carbon also appears to be dynamically persistent. According to our investigations, the values for the elasticity within the iron‐sulfur cluster have to be corrected too. These new details on the mechano‐chemical properties of the FeMo cofactor will be important for elucidating the catalytic cycle of nitrogen fixation. By implementing our new algorithm in the freely available COMPLIANCE program, the dependence on the coordinates during the calculation of Hesse matrices is eliminated completely.
An Unsaturated Quinolone N‐Oxide of Pseudomonas aeruginosa Modulates Growth and Virulence of Staphylococcus aureus
Authors: Szamosvári Dávid , Böttcher Thomas
Published: May 2017

The pathogen Pseudomonas aeruginosa produces over 50 different quinolones, 16 of which belong to the class of 2‐alkyl‐4‐quinolone N‐oxides (AQNOs) with various chain lengths and degrees of saturation. We present the first synthesis of a previously proposed unsaturated compound that is confirmed to be present in culture extracts of P. aeruginosa, and its structure is shown to be trans‐Δ1‐2‐(non‐1‐enyl)‐4‐quinolone N‐oxide. This compound is the most active agent against S.  aureus, including MRSA strains, by more than one order of magnitude whereas its cis isomer is inactive. At lower concentrations, the compound induces small‐colony variants of S. aureus, reduces the virulence by inhibiting hemolysis, and inhibits nitrate reductase activity under anaerobic conditions. These studies suggest that this unsaturated AQNO is one of the major agents that are used by P. aeruginosa to modulate competing bacterial species.
Heterogeneous Jacobsen's catalyst on alkoxyl‐modified zirconium poly (styrene‐phenylvinylphosphonate)‐phosphate (ZPS‐PVPA) for asymmetric epoxidation
Authors: Huang Jing , Ding Weigang , Cai Jiali
Published: May 2017

Chiral Jacobsen's catalysts grafted onto alkoxyl‐modified ZPS‐PVPA exhibit excellent activities (conv%, up to 96; sele%, up to 96; ee%, up to >99) in the asymmetric epoxidations of unfunctionalized olefins. The superior stabilities and the comfortable dispositions in large‐scale reactions contribute to the potential applications in industry.
Rheological study on the thermoinduced gelation behavior of poly(N‐isopropylacrylamide‐co‐acrylic acid) microgel suspensions
Authors: Wang Tao , Jin Liang , Song Yanan , Li Jiaxi , Gao Yu , Shi Shan
Published: May 2017

Submicron‐sized thermoresponsive poly(N‐isopropylacrylamide‐co‐acrylic acid) microgels were synthesized by soap‐free emulsion polymerization. The physical state of the microgel suspensions, in a wide range of polymer concentrations (1.1–7.1 wt %), transformed from fluid to gel when the temperature was elevated across their volume phase transition temperature at pH = 3.0. Such thermoinduced gelation behavior was studied in detail by small‐deformation oscillatory rheological measurements within the linear viscoelastic region. It was found that the gelation temperature was strongly affected by the polymer concentration, decreasing as the polymer concentration increased. The gelation kinetics showed that the suspension gelled more quickly at either larger polymer concentration or higher isothermal heating temperature. In an isothermal frequency sweep for the as‐formed gels, both storage and loss moduli,G′andG″, exhibited a power‐law behavior, that is,G′(ω) ∼ ω0.2–0.4andG″(ω) ∼ ω0.46−0.50within the frequency range whereG′dominatesG″. In addition, the elasticity of the gels, which results from the attractive particle bonds, increased markedly with increasing polymer concentration. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2017,134, 45259.
Projection in snowfall characteristics over the European Alps and its sensitivity to the SST changes: results from a 50 km resolution AGCM
Authors: Freychet N. , Hsu H.‐H. , Duchez A. , Tu C.‐Y.
Published: May 2017

The end‐of‐century projection of the snowfall characteristics over the Alps region is studied using the 50‐km resolution atmospheric global climate model, HiRAM (high‐resolution atmospheric model). The model is forced by three different patterns of projections in the sea surface temperature (SST) in order to assess the sensitivity of snowfall characteristics to theses patterns. It is found that the mean snowfall intensity and frequency is poorly affected by the differences in SST forcing. However, the projections of heavy snowfall events strongly depend on the SST scenario. The changes in temperature and frequency of precipitation and freezing days over the Alps were investigated. We found that these variables did not exhibit a clear dependence to the SST scenario and could not explain the differences observed in snowfall projections. Changes in the moisture transport from the Atlantic Ocean to Europe were found significantly different between each scenario and are assumed to be the main factor affecting the projections of snowfalls, by providing more or less moisture supply.
Anomalous variation in summer tropical cyclone activity by preceding winter Aleutian low oscillation
Authors: Choi Jae‐Won , Cha Yumi
Published: May 2017

This research found a high‐positive correlation between Aleutian low oscillation during the winter (November–March) and tropical cyclone (TC) genesis frequency during the following summer (July–September) over a 26‐year period (1982–2007). In the years with high Aleutian low oscillation, a number of characteristics were analyzed. In the preceding winter, anomalous pressure patterns, such as south‐low and north‐high at the low level, formed as the center for the regions near 20°N in the western North Pacific. Sea ice concentration was less than the average around the Sea of Okhotsk and the Bering Sea, which weakened the Aleutian Low in this area. This anomalous pressure pattern continued until the following summer, and it reinforced the anomalous easterlies at the mid‐latitudes (20°–40°N) in East Asia and contributed to the high TC passage frequency in the East Asian continent.
Augmented probability simulation for accelerated life test design
Authors: Polson Nicholas G. , Soyer Refik
Published: May 2017

Designing accelerated life tests presents a number of conceptual and computational challenges. We propose a Bayesian decision‐theoretic approach for selecting an optimal stress‐testing schedule and develop an augmented probability simulation approach to obtain the optimal design. The notion of a ‘dual utility probability density’ enables us to invoke the concept of a conjugate utility function. For accelerated life tests, this allows us to construct an augmented probability simulation that simultaneously optimizes and calculates the expected utility. In doing so, we circumvent many of the computational difficulties associated with evaluating pre‐posterior expected utilities. To illustrate our methodology, we consider a single‐stage accelerated life test design; our approach naturally extends to multiple‐stage designs. Finally, we conclude with suggestions for further research. Copyright © 2017 John Wiley & Sons, Ltd.
Inhibitory Activity of Halogenated 3‐Benzylidenechroman‐4‐ones Against Lipopolysaccharide‐stimulated Reactive Oxygen Species Production in RAW 264.7 Macrophages
Authors: Thapa Magar Til Bahadur , Kadayat Tara Man , Oh Hye Jin , Park Pil‐Hoon , Lee Eung‐Seok
Published: May 2017

Chromanone‐containing compounds have been reported to possess several important biological activities. As a part of our continuing effort for discovering potent anti‐inflammatory agents, a series of halogen‐containing 3‐benzylidenechroman‐4‐ones (1–15) were synthesized, and evaluated for their inhibitory effect on lipopolysaccharide (LPS)‐stimulated reactive oxygen species (ROS) production in RAW 264.7 macrophages. Compounds 4 and 10 exhibited significant inhibitory activity (IC50
 = 5.09 ± 1.27 and 5.11 ± 0.51 μM, respectively) against LPS‐stimulated ROS production in RAW 264.7 macrophages.
Fabrication of g‐C3N4/Au/C‐TiO2 Hollow Structures as Visible‐Light‐Driven Z‐Scheme Photocatalysts with Enhanced Photocatalytic H2 Evolution
Authors: Zou Yajun , Shi Jian‐Wen , Ma Dandan , Fan Zhaoyang , Niu Chunming , Wang Lianzhou
Published: May 2017

The Z‐scheme photocatalytic system for water splitting based on semiconductors has exhibited great potential for H2 fuel production from renewable resources. In this work, we constructed g‐C3N4/Au/C‐TiO2 hollow spheres as an all‐solid‐state Z‐scheme photocatalytic system with Au nanoparticles as the electron mediator. The as‐synthesized g‐C3N4/Au/C‐TiO2 photocatalyst showed a remarkably enhanced photocatalytic H2 evolution rate under visible‐light irradiation (λ>420 nm), which was 86 and 42 times higher than those of pure C‐TiO2 and g‐C3N4, respectively. The enhancement of photocatalytic performance can be mainly attributed to the intentionally designed Z‐scheme system, which not only promoted the efficient transfer and separation of photogenerated electron–hole pairs, but also retained the strong redox ability of the charge carriers. In addition, the Z‐scheme system also achieved high visible‐light absorption and utilization owing to the surface plasmon resonance (SPR) effect of Au nanoparticles and hollow structures of C‐TiO2. All the factors synergistically promote the photocatalytic activity of the g‐C3N4/Au/C‐TiO2 hollow nanospheres, providing a promising method for the rational design of highly efficient visible‐light‐driven photocatalysts.
Theoretical Investigation into Suitable Pore Sizes of Membranes for Vanadium Redox Flow Batteries
Authors: Liu Zaichun , Li Ruilian , Chen Jizhong , Wu Xiongwei , Zhang Kai , Mo Jun , Yuan Xinhai , Jiang Hongmei , Holze Rudolf , Wu Yuping
Published: May 2017

For the first time, a three‐dimensional (3D) volume calculation model based on total electrostatic potential analysis and density functional calculations is applied to study the volume differences between hydrated multivalent vanadium ions (V2+, V3+, VO2+, and
) and charge‐balancing ions (H3O+,
and
) encountered in the electrolyte solutions of vanadium redox flow batteries (VRBs). The calculated results indicate that radii of all charge‐balancing ions are less than 3.01 Å and of all hydrated multivalent vanadium ions are greater than 3.78 Å. The results of our calculations also suggest that cation‐exchange membranes with pore sizes ranging from 3.98 to 7.56 Å and anion‐exchange membranes with pore sizes ranging from 6.02 to 7.56 Å are suitable for the VRB application. These computational results agree very well with reported experimental results and provide valuable guidance for the selection and design of membranes on the molecular level for VRB applications.
Fundamental Characteristics of a Glucose Transistor with a Chemically Functional Interface
Authors: Uematsu Yuta , Kajisa Taira , Sakata Toshiya
Published: May 2017

Semiconductor‐based biosensors are suitable for the detection of small molecules such as glucose as long as they have molecular charges. However, biological samples include various ionic molecules such as proteins; thus, their nonspecific adsorption should be prevented to reduce background noise. In this study, we optimized a field‐effect transistor (FET)‐based glucose sensor, that is, a glucose transistor, for more precise and highly sensitive glucose sensing. Using the glucose transistor modified with 4‐mercaptophenylboronic acid (PBA) on a gold gate electrode, we found that the detection sensitivity to glucose was increased to approximately 60 mV/decade from about 40 μM. This means that the PBA on the gate induced a diol‐binding site with glucose through an equilibrium reaction, resulting in an increase in the density of negative charges in the PBA‐glucose conjugate. Moreover, an oligoethyleneglycol (OEG) monolayer was coated on the gate as a molecular sieve interface so that the PBA molecules were embowered in the OEG membrane, but low‐molecular‐weight glucose could pass between the OEG molecules and reach the PBA molecules at the gate. The detection sensitivity of the biosensor with the optimized glucose transistor to glucose remained, to some extent, even in a solution including albumin. Thus, a platform based on the optimized glucose transistor is available for the practical use of a novel sensor that can detect glucose even at the low concentrations included in biological fluids.
Feasibility of N2 Binding and Reduction to Ammonia on Fe‐Deposited MoS2 2D Sheets: A DFT Study
Authors: Azofra Luis Miguel , Sun Chenghua , Cavallo Luigi , MacFarlane Douglas R.
Published: May 2017

Based on the structure of the nitrogenase FeMo cofactor (FeMoco), it is reported that Fe deposited on MoS2 2D sheets exhibits high selectivity towards the spontaneous fixation of N2 against chemisorption of CO2 and H2O. DFT predictions also indicate the ability of this material to convert N2 into NH3 with a maximum energy input of 1.02 eV as an activation barrier for the first proton–electron pair transfer.
Metal Confinement through N‐(9‐Alkyl)fluorenyl‐Substituted N‐Heterocyclic Carbenes and Its Consequences in Gold‐Catalysed Reactions Involving Enynes
Authors: Teci Matthieu , Hueber Damien , Pale Patrick , Toupet Loïc , Blanc Aurélien , Brenner Eric , Matt Dominique
Published: May 2017

A series of gold(I) and gold(III) complexes containing bulky bis‐N,N′‐(9‐alkylfluorenyl) heterocyclic carbene (RF‐NHC) ligands have been prepared in high yields from appropriate imidazolinium, imidazolium and benzimidazolium salts. In all complexes, the carbene ligand provides high steric protection of the Au−X bond trans to the carbenic C atom. Irrespective of the metal oxidation state, the complexes showed high efficiency in a tandem 3,3‐rearrangement/Nazarov reaction of an enynyl acetate. One of the AuIII complexes, [AuCl3(RF‐NHC)], was further found to be suitable for the efficient cyclisation of a propargylcarboxamide. Furthermore, unlike related NHC–gold(I) complexes based on conventional bulky N‐heterocyclic carbenes (notably, 1,3‐bis‐(2,6‐diisopropylphenyl)imidazol‐2‐ylidene (IPr), 1,3‐bis‐(2,4,6‐trimethylphenyl)imidazol‐2‐ylidene (IMes) and 1,3‐(bis‐tert‐butyl)imidazol‐2‐ylidene (ItBu)), the studied [AuICl(RF‐NHC)] complexes catalysed the conversion of a 1,6‐enyne in the presence of indole into a single product; this arises from the embracing character of the ligand, which prevents indole addition on one of the catalytic intermediates. A structure/selectivity relationship was established for all carbenes tested that took into account percent buried volumes and topographic steric maps. The results illustrate the high potential of confining NHCs in organic synthesis.
Synthesis and Antineoplastic Evaluation of Mitochondrial Complex II (Succinate Dehydrogenase) Inhibitors Derived from Atpenin A5
Authors: Wang Hezhen , Huwaimel Bader , Verma Kshitij , Miller James , Germain Todd M. , Kinarivala Nihar , Pappas Dimitri , Brookes Paul S. , Trippier Paul C.
Published: May 2017

Mitochondrial complex II (CII) is an emerging target for numerous human diseases. Sixteen analogues of the CII inhibitor natural product atpenin A5 were prepared to evaluate the structure–activity relationship of the C5 pyridine side chain. The side chain ketone moiety was determined to be pharmacophoric, engendering a bioactive conformation. One analogue, 1‐(2,4‐dihydroxy‐5,6‐dimethoxypyridin‐3‐yl)hexan‐1‐one (16 c), was found to have a CII IC50 value of 64 nm, to retain selectivity for CII over mitochondrial complex I (>156‐fold), and to possess a ligand‐lipophilicity efficiency (LLE) of 5.62, desirable metrics for a lead compound. This derivative and other highly potent CII inhibitors show potent and selective anti‐proliferative activity in multiple human prostate cancer cell lines under both normoxia and hypoxia, acting to inhibit mitochondrial electron transport.
Near‐optimal dynamic priority scheduling strategy for instance‐intensive business workflows in cloud computing
Authors: Xu Rongbin , Wang Yeguo , Huang Wei , Yuan Dong , Xie Ying , Yang Yun
Published: May 2017

Utilization of cloud computing resources has made a fast growth in e‐business. Business and government agencies often need to handle large volume of service requests, the so‐called instance‐intensive business processes in a constrained period. On‐time completion for instance‐intensive business processes within the constrained time is a very important issue. In the past few years, traditional optimal task scheduling has been well researched and proven to be a nondeterministic polynomial (NP) time–complete problem. So many heuristic and metaheuristic algorithms are put forward to solve the issue with near‐optimal solutions. However, most of them just treat a single workflow instance as a multistep task without considering that steps within a task can be different types of activities. To explain multistep features of business workflows, a typical motivating instance‐intensive business example of security exchange and a multistep scheduling model for business workflows are introduced in this paper. Then our near‐optimal dynamic priority scheduling (DPS) strategy is proposed on the basis of the idea of Min‐Min heuristic algorithm and greedy philosophy. Compared to the first come first served and constrained Min‐Min by makespan and standard deviation, DPS can make a more optimized choice in each round of scheduling towards overall outcome. To show the effectiveness of DPS, theoretical minimum execution time (METtheory) is used as a benchmark for evaluation based on simulation. The results show that the ratios between METtheory and DPS are more than 98.5% by scheduling different orders of magnitude tasks from 1000 to 1 000 000. In particular, the ratio between METtheory and DPS is nearly 99.9% with 1 000 000 tasks, which means that our DPS can get the near‐optimal result when scheduling large number of tasks.
Single‐Molecule and Ensemble Diffusivities in Individual Nanopores with Spatially Dependent Mobility
Authors: Rybka Julia , Kärger Jörg , Tallarek Ulrich
Published: May 2017

We investigated single‐molecule and ensemble diffusivities in a silica nanopore with a chemically modified surface by molecular dynamics simulations. Solutes with graded polarity (nonpolar ethylbenzene and moderately polar benzyl alcohol) were equilibrated with a 40:60 v/v water/acetonitrile solvent in a 10 nm pore, the surface of which was rendered hydrophobic by modification with alkyl chains. Simulations enable detailed sampling of spatially dependent solvent and solute mobilities, which originate from microheterogeneity induced by the surface modification. Acetonitrile is enriched near the ends of the alkyl chains and forms a high‐mobility interface region between the (nonpolar) bonded phase at the surface and the (polar) bulk liquid in the center of the pore. Solvent and solute diffusivities calculated from the time average of a single molecule and from the ensemble average over all molecules, respectively, revealed excellent agreement, which implies validity of ergodicity. The molecular‐simulation approach to investigate the time average of a single molecule, on the one hand, and the ensemble average over a larger number of molecules, on the other hand, is general and can be adapted for a variety of surfaces, solvents, and solute molecules by using pores with tailored geometries and surface modifications.
Influence of the temperature and composition on the crystal structure of the AgBiSe2‐AgBiS2 system
Authors: Mitra Sunanda , Berardan David
Published: May 2017

We report on the synthesis and structural study of the system AgBiSe2‐AgBiS2. Single phase samples have been synthesized for every compositions of the solid solution, we have studied the temperature dependence of the crystal structure using high‐temperature X‐ray diffraction coupled to DSC, and established the structural phase diagram of the system. From this diagram, sulfur‐rich samples exhibit one structural phase transition from a low temperature hexagonal phase to a high temperature cubic one, whereas selenium‐rich samples also exhibit an intermediate rhombohedral phase, with a limit between the 2‐phases and 3‐phases region at Se = 0.8. Besides, significant changes of the volume of the unit cell have been observed at the phase transitions, coupled to crystal structure dependent coefficients of thermal expansion.
Herbal Formula, Baogan Yihao (BGYH), Prevented Dimethylnitrosamine(DMN)‐Induced Liver Injury in Rats
Authors: Liu Xiujie , Su Jing , Shi Yu , Guo Ying , Suheryani Imran , Zhao Shicong , Deng Yulin , Meng Weiwei , Chen Yan , Sun Lili , Dai Rongji
Published: May 2017

Preclinical Research

Baogan Yihao (BGYH) is a traditional Chinese herbal medicine for the treatment of chronic liver diseases. In this study, the effects of BGYH on dimethylnitrosamine (DMN)‐induced liver fibrosis were investigated using a rat model. BGYH alleviate liver damage, as indicated by decreased levels of AST, ALT, γ‐GT, and AKP. BGYH also prevented collagen deposition and reduced pathological tissue injury in liver tissue. In fibrosis, high levels of α‐SMA and TGF‐β in liver tissue were markedly attenuated by BGYH. The inhibitory effect of BGYH on HSC‐T6 proliferation demonstrated that BGYH exhibited significant hepatoprotective and antifibrogenic effects on DMN‐induced liver injury. These findings suggest that BGYH may have therapeutic potential in the prevention and therapy of liver fibrosis. Drug Dev Res 78 : 155‐163, 2017. © 2017 Wiley Periodicals, Inc.
Remote sensing‐based landscape indicators for the evaluation of threatened‐bird habitats in a tropical forest
Authors: Singh Minerva , Tokola Timo , Hou Zhengyang , Notarnicola Claudia
Published: May 2017

Avian species persistence in a forest patch is strongly related to the degree of isolation and size of a forest patch and the vegetation structure within a patch and its matrix are important predictors of bird habitat suitability. A combination of space‐borne optical (Landsat), ALOS‐PALSAR (radar), and airborne Light Detection and Ranging (LiDAR) data was used for assessing variation in forest structure across forest patches that had undergone different levels of forest degradation in a logged forest—agricultural landscape in Southern Laos. The efficacy of different remote sensing (RS) data sources in distinguishing forest patches that had different seizes, configurations, and vegetation structure was examined. These data were found to be sensitive to the varying levels of degradation of the different patch categories. Additionally, the role of local scale forest structure variables (characterized using the different RS data and patch area) and landscape variables (characterized by distance from different forest patches) in influencing habitat preferences of International Union for Conservation of Nature (IUCN) Red listed birds found in the study area was examined. A machine learning algorithm, MaxEnt, was used in conjunction with these data and field collected geographical locations of the avian species to identify the factors influencing habitat preference of the different bird species and their suitable habitats. Results show that distance from different forest patches played a more important role in influencing habitat suitability for the different avian species than local scale factors related to vegetation structure and health. In addition to distance from forest patches, LiDAR‐derived forest structure and Landsat‐derived spectral variables were important determinants of avian habitat preference. The models derived using MaxEnt were used to create an overall habitat suitability map (HSM) which mapped the most suitable habitat patches for sustaining all the avian species. This work also provides insight that retention of forest patches, including degraded and isolated forest patches in addition to large contiguous forest patches, can facilitate bird species retention within tropical agricultural landscapes. It also demonstrates the effective use of RS data in distinguishing between forests that have undergone varying levels of degradation and identifying the habitat preferences of different bird species. Practical conservation management planning endeavors can use such data for both landscape scale monitoring and habitat mapping.
The effects of historical fragmentation on major histocompatibility complex class II β and microsatellite variation in the Aegean island reptile, Podarcis erhardii
Authors: Santonastaso Trent , Lighten Jackie , van Oosterhout Cock , Jones Kenneth L. , Foufopoulos Johannes , Anthony Nicola M.
Published: May 2017

The major histocompatibility complex (MHC) plays a key role in disease resistance and is the most polymorphic gene region in vertebrates. Although habitat fragmentation is predicted to lead to a loss in MHC variation through drift, the impact of other evolutionary forces may counter this effect. Here we assess the impact of selection, drift, migration, and recombination on MHC class II and microsatellite variability in 14 island populations of the Aegean wall lizard Podarcis erhardii. Lizards were sampled from islands within the Cyclades (Greece) formed by rising sea levels as the last glacial maximum approximately 20,000 before present. Bathymetric data were used to determine the area and age of each island, allowing us to infer the corresponding magnitude and timing of genetic bottlenecks associated with island formation. Both MHC and microsatellite variation were positively associated with island area, supporting the hypothesis that drift governs neutral and adaptive variation in this system. However, MHC but not microsatellite variability declined significantly with island age. This discrepancy is likely due to the fact that microsatellites attain mutation‐drift equilibrium more rapidly than MHC. Although we detected signals of balancing selection, recombination and migration, the effects of these evolutionary processes appeared negligible relative to drift. This study demonstrates how land bridge islands can provide novel insights into the impact of historical fragmentation on genetic diversity as well as help disentangle the effects of different evolutionary forces on neutral and adaptive diversity.