bluuebunny/crossref_metadata_2025 huggingface dataset:
Neural activity in cortico-basal ganglia circuits of juvenile songbirds encodes performance during goal-directed learning
Authors: Achiro Jennifer M , Shen John , Bottjer Sarah W
Published: December 2017

Cortico-basal ganglia circuits are thought to mediate goal-directed learning by a process of outcome evaluation to gradually select appropriate motor actions. We investigated spiking activity in core and shell subregions of the cortical nucleus LMAN during development as juvenile zebra finches are actively engaged in evaluating feedback of self-generated behavior in relation to their memorized tutor song (the goal). Spiking patterns of single neurons in both core and shell subregions during singing correlated with acoustic similarity to tutor syllables, suggesting a process of outcome evaluation. Both core and shell neurons encoded tutor similarity via either increases or decreases in firing rate, although only shell neurons showed a significant association at the population level. Tutor similarity predicted firing rates most strongly during early stages of learning, and shell but not core neurons showed decreases in response variability across development, suggesting that the activity of shell neurons reflects the progression of learning.
Inferring genetic interactions from comparative fitness data
Authors: Crona Kristina , Gavryushkin Alex , Greene Devin , Beerenwinkel Niko
Published: December 2017

Darwinian fitness is a central concept in evolutionary biology. In practice, however, it is hardly possible to measure fitness for all genotypes in a natural population. Here, we present quantitative tools to make inferences about epistatic gene interactions when the fitness landscape is only incompletely determined due to imprecise measurements or missing observations. We demonstrate that genetic interactions can often be inferred from fitness rank orders, where all genotypes are ordered according to fitness, and even from partial fitness orders. We provide a complete characterization of rank orders that imply higher order epistasis. Our theory applies to all common types of gene interactions and facilitates comprehensive investigations of diverse genetic interactions. We analyzed various genetic systems comprising HIV-1, the malaria-causing parasite Plasmodium vivax, the fungus Aspergillus niger, and the TEM-family of β-lactamase associated with antibiotic resistance. For all systems, our approach revealed higher order interactions among mutations.
Inhibition of intracellular lipolysis promotes human cancer cell adaptation to hypoxia
Authors: Zhang Xiaodong , Saarinen Alicia M , Hitosugi Taro , Wang Zhenghe , Wang Liguo , Ho Thai H , Liu Jun
Published: December 2017

Tumor tissues are chronically exposed to hypoxia owing to aberrant vascularity. Lipid droplet (LD) accumulation is a hallmark of hypoxic cancer cells, yet how LDs form and function during hypoxia remains poorly understood. Herein, we report that in various cancer cells upon oxygen deprivation, HIF-1 activation down-modulates LD catabolism mediated by adipose triglyceride lipase (ATGL), the key enzyme for intracellular lipolysis. Proteomics and functional analyses identified hypoxia-inducible gene 2 (HIG2), a HIF-1 target, as a new inhibitor of ATGL. Knockout of HIG2 enhanced LD breakdown and fatty acid (FA) oxidation, leading to increased ROS production and apoptosis in hypoxic cancer cells as well as impaired growth of tumor xenografts. All of these effects were reversed by co-ablation of ATGL. Thus, by inhibiting ATGL, HIG2 acts downstream of HIF-1 to sequester FAs in LDs away from the mitochondrial pathways for oxidation and ROS generation, thereby sustaining cancer cell survival in hypoxia.
Simulations indicate that scores of lionfish (Pterois volitans) colonized the Atlantic Ocean
Authors: Selwyn Jason D. , Johnson John E. , Downey-Wall Alan M. , Bynum Adam M. , Hamner Rebecca M. , Hogan J. Derek , Bird Christopher E.
Published: December 2017

The invasion of the western Atlantic Ocean by the Indo-Pacific red lionfish (Pterois volitans) has had devastating consequences for marine ecosystems. Estimating the number of colonizing lionfish can be useful in identifying the introduction pathway and can inform policy decisions aimed at preventing similar invasions. It is well-established that at least ten lionfish were initially introduced. However, that estimate has not faced probabilistic scrutiny and is based solely on the number of haplotypes in the maternally-inherited mitochondrial control region. To rigorously estimate the number of lionfish that were introduced, we used a forward-time, Wright-Fisher, population genetic model in concert with a demographic, life-history model to simulate the invasion across a range of source population sizes and colonizing population fecundities. Assuming a balanced sex ratio and no Allee effects, the simulations indicate that the Atlantic population was founded by 118 (54–514, 95% HPD) lionfish from the Indo-Pacific, the Caribbean by 84 (22–328, 95% HPD) lionfish from the Atlantic, and the Gulf of Mexico by at least 114 (no upper bound on 95% HPD) lionfish from the Caribbean. Increasing the size, and therefore diversity, of the Indo-Pacific source population and fecundity of the founding population caused the number of colonists to decrease, but with rapidly diminishing returns. When the simulation was parameterized to minimize the number of colonists (highθand relative fecundity), 96 (48–216, 95% HPD) colonists were most likely. In a more realistic scenario with Allee effects (e.g., 50% reduction in fecundity) plaguing the colonists, the most likely number of lionfish increased to 272 (106–950, 95% HPD). These results, in combination with other published data, support the hypothesis that lionfish were introduced to the Atlantic via the aquarium trade, rather than shipping. When building the model employed here, we made assumptions that minimize the number of colonists, such as the lionfish being introduced in a single event. While we conservatively modelled the introduction pathway as a single release of lionfish in one location, it is more likely that a combination of smaller and larger releases from a variety of aquarium trade stakeholders occurred near Miami, Florida, which could have led to even larger numbers of colonists than simulated here. Efforts to prevent future invasions via the aquarium trade should focus on the education of stakeholders and the prohibition of release, with adequate rewards for compliance and penalties for violations.
ROCK AND ROLL E CULTURA: A PRODUÇÃO DISCURSIVA DA CRISE AMBIENTAL EM TEMPOS CONTEMPORÂNEOS
Authors: Vieira Virgínia Tavares , Henning Paula Corrêa
Published: December 2017

O presente artigo investiga a forma como o rock and roll vem contribuindo para pensarmos na crise ambiental que se instala na atualidade. Para responder a essa investigação, selecionaram-se letras de rock de seis bandas de países ocidentais que tratam da temática ambiental. Apoiado em autores como Michel Foucault e Zygmunt Bauman, o artigo buscou problematizar que enunciações de natureza, homem e degradação ambiental estavam presentes no material colocado em suspenso. O caminho metodológico selecionado para operar com o material empírico trata de algumas ferramentas da análise do discurso, a partir de Michel Foucault, trabalhando especificamente com os conceitos de disurso e enunciado. Diante do material analisado, o estudo apontou para um enunciado potente que nos auxilia olhar para a problemática ambiental de forma apocalíptica.
Phosphorylation at Thr432 induces structural destabilization of the CII ring in the circadian oscillator KaiC
Authors: Oyama Katsuaki , Azai Chihiro , Matsuyama Jun , Terauchi Kazuki
Published: December 2017

KaiC is the central oscillator protein in the cyanobacterial circadian clock. KaiC oscillates autonomously between phosphorylated and dephosphorylated states on a 24‐h cycle in vitro by mixing with KaiA and KaiB in the presence of ATP. KaiC forms a C6‐symmetrical hexamer, which is a double ring structure of homologous N‐terminal and C‐terminal domains termed CI and CII, respectively. Here, through the characterization of an isolated CII domain protein, CIIKaiC, we show that phosphorylation of KaiC Thr432 destabilizes the hexameric state of the CII ring to a monomeric state. The results suggest that the stable hexameric CI ring acts as a molecular bundle to hold the CII ring, which undergoes dynamic structural changes upon phosphorylation.
NADPH‐dependent 5‐keto‐D‐gluconate reductase is a part of the fungal pathway for D‐glucuronate catabolism
Authors: Kuivanen Joosu , Richard Peter
Published: December 2017

NADPH‐dependent 5‐keto‐D‐gluconate reductase was identified as a missing element in the pathway for D‐glucuronate catabolism in fungi. The disruption of the gene, gluF, by CRISPR/Cas9 in the filamentous fungus Aspergillus niger resulted in a strain unable to catabolise D‐glucuronate. The purified GluF protein was characterized and kcat and Km values of 23.7 ± 1.8 s−1 and 3.2 ± 0.1 mm for 5‐keto‐D‐gluconate, respectively, were determined. The enzyme is reversible and is active with NADP+ and D‐gluconate. We suggest a pathway for D‐glucuronate catabolism with the intermediates L‐gulonate, 2‐keto‐L‐gulonate, L‐idonate, 5‐keto‐D‐gluconate, D‐gluconate and D‐gluconate‐6‐phosphate which is a part of the pentose phosphate pathway. A fungal enzyme activity for the conversion of L‐gulonate to 2‐keto‐L‐gulonate remains to be identified.
Optimum Sea Surface Displacement and Fault Slip Distribution of the 2017 Tehuantepec Earthquake (Mw 8.2) in Mexico Estimated From Tsunami Waveforms
Authors: Gusman Aditya Riadi , Mulia Iyan E. , Satake Kenji
Published: December 2017

The 2017 Tehuantepec earthquake (Mw 8.2) was the first great normal fault event ever instrumentally recorded to occur in the Middle America Trench. The earthquake generated a tsunami with an amplitude of 1.8 m (height = 3.5 m) in Puerto Chiapas, Mexico. Tsunami waveforms recorded at coastal tide gauges and offshore buoy stations were used to estimate the optimum sea surface displacement without assuming any fault. Our optimum sea surface displacement model indicated that the maximum uplift of 0.5 m is located near the trench and the maximum subsidence of 0.8 m on the coastal side near the epicenter. We then estimated the fault slip distribution that can best explain the optimum sea surface displacement assuming 10 different fault geometries. The best model suggests that a compact region of large slip (3–6 m) extends from a depth of 30 km to 90 km, centered at a depth of 60 km.
Mesoscale Dynamical Regimes in the Midlatitudes
Authors: Craig G. C. , Selz T.
Published: December 2017

The atmospheric mesoscales are characterized by a complex variety of meteorological phenomena that defy simple classification. Here a full space‐time spectral analysis is carried out, based on a 7 day convection‐permitting simulation of springtime midlatitude weather on a large domain. The kinetic energy is largest at synoptic scales, and on the mesoscale it is largely confined to an “advective band” where space and time scales are related by a constant of proportionality which corresponds to a velocity scale of about 10 m s−1. Computing the relative magnitude of different terms in the governing equations allows the identification of five dynamical regimes. These are tentatively identified as quasi‐geostrophic flow, propagating gravity waves, stationary gravity waves related to orography, acoustic modes, and a weak temperature gradient regime, where vertical motions are forced by diabatic heating.
Improved Seasonal Prediction of European Summer Temperatures With New Five‐Layer Soil‐Hydrology Scheme
Authors: Bunzel Felix , Müller Wolfgang A. , Dobrynin Mikhail , Fröhlich Kristina , Hagemann Stefan , Pohlmann Holger , Stacke Tobias , Baehr Johanna
Published: December 2017

We evaluate the impact of a new five‐layer soil‐hydrology scheme on seasonal hindcast skill of 2 m temperatures over Europe obtained with the Max Planck Institute Earth System Model (MPI‐ESM). Assimilation experiments from 1981 to 2010 and 10‐member seasonal hindcasts initialized on 1 May each year are performed with MPI‐ESM in two soil configurations, one using a bucket scheme and one a new five‐layer soil‐hydrology scheme. We find the seasonal hindcast skill for European summer temperatures to improve with the five‐layer scheme compared to the bucket scheme and investigate possible causes for these improvements. First, improved indirect soil moisture assimilation allows for enhanced soil moisture‐temperature feedbacks in the hindcasts. Additionally, this leads to improved prediction of anomalies in the 500 hPa geopotential height surface, reflecting more realistic atmospheric circulation patterns over Europe.
Will Half a Degree Make a Difference? Robust Projections of Indices of Mean and Extreme Climate in Europe Under 1.5°C, 2°C, and 3°C Global Warming
Authors: Dosio Alessandro , Fischer Erich M.
Published: December 2017

Based on high‐resolution models, we investigate the change in climate extremes and impact‐relevant indicators over Europe under different levels of global warming. We specifically assess the robustness of the changes and the benefits of limiting warming to 1.5°C instead of 2°C. Compared to 1.5°C world, a further 0.5°C warming results in a robust change of minimum summer temperature indices (mean, Tn10p, and Tn900p) over more than 70% of Europe. Robust changes (more than 0.5°C) in maximum temperature affect smaller areas (usually less than 20%). There is a substantial nonlinear change of fixed‐threshold indices, with more than 60% increase of the number of tropical nights over southern Europe and more than 50% decrease in the number of frost days over central Europe. The change in mean precipitation due to 0.5°C warming is mostly nonsignificant at the grid point level, but, locally, it is accompanied by a more marked change in extreme rainfall.
Core‐Exsolved SiO2 Dispersal in the Earth's Mantle
Authors: Helffrich George , Ballmer Maxim D. , Hirose Kei
Published: December 2017

SiO2 may have been expelled from the core directly following core formation in the early stages of Earth's accretion and onward through the present day. On account of SiO2's low density with respect to both the core and the lowermost mantle, we examine the process of SiO2 accumulation at the core‐mantle boundary (CMB) and its incorporation into the mantle by buoyant rise. Today, if SiO2 is 100–10,000 times more viscous than lower mantle material, the dimensions of SiO2 diapirs formed by the viscous Rayleigh‐Taylor instability at the CMB would cause them to be swept into the mantle as inclusions of 100 m–10 km diameter. Under early Earth conditions of rapid heat loss after core formation, SiO2 diapirs of ∼1 km diameter could have risen independently of mantle flow to their level of neutral buoyancy in the mantle, trapping them there due to a combination of intrinsically high viscosity and neutral buoyancy. We examine the SiO2 yield by assuming Si + O saturation at the conditions found at the base of a magma ocean and find that for a range of conditions, dispersed bodies could reach as high as 8.5 vol % in parts of the lower mantle. At such low concentration, their effect on aggregate seismic wave speeds is within observational seismology uncertainty. However, their presence can account for small‐scale scattering in the lower mantle due to the bodies' large‐velocity contrast. We conclude that the shallow lower mantle (700–1,500 km depth) could harbor SiO2 released in early Earth times.
The Met Office Global Coupled Model 3.0 and 3.1 (GC3.0 and GC3.1) Configurations
Authors: Williams K. D. , Copsey D. , Blockley E. W. , Bodas‐Salcedo A. , Calvert D. , Comer R. , Davis P. , Graham T. , Hewitt H. T. , Hill R. , Hyder P. , Ineson S. , Johns T. C. , Keen A. B. , Lee R. W. , Megann A. , Milton S. F. , Rae J. G. L. , Roberts M. J. , Scaife A. A. , Schiemann R. , Storkey D. , Thorpe L. , Watterson I. G. , Walters D. N. , West A. , Wood R. A. , Woollings T. , Xavier P. K.
Published: December 2017

The Global Coupled 3 (GC3) configuration of the Met Office Unified Model is presented. Among other applications, GC3 is the basis of the United Kingdom's submission to the Coupled Model Intercomparison Project 6 (CMIP6). This paper documents the model components that make up the configuration (although the scientific descriptions of these components are in companion papers) and details the coupling between them. The performance of GC3 is assessed in terms of mean biases and variability in long climate simulations using present‐day forcing. The suitability of the configuration for predictability on shorter time scales (weather and seasonal forecasting) is also briefly discussed. The performance of GC3 is compared against GC2, the previous Met Office coupled model configuration, and against an older configuration (HadGEM2‐AO) which was the submission to CMIP5. In many respects, the performance of GC3 is comparable with GC2, however, there is a notable improvement in the Southern Ocean warm sea surface temperature bias which has been reduced by 75%, and there are improvements in cloud amount and some aspects of tropical variability. Relative to HadGEM2‐AO, many aspects of the present‐day climate are improved in GC3 including tropospheric and stratospheric temperature structure, most aspects of tropical and extratropical variability and top‐of‐atmosphere and surface fluxes. A number of outstanding errors are identified including a residual asymmetric sea surface temperature bias (cool northern hemisphere, warm Southern Ocean), an overly strong global hydrological cycle and insufficient European blocking.
Complex Plane Specular Meteor Radar Interferometry
Authors: Vaudrin Cody V. , Palo Scott E. , Chau Jorge L.
Published: December 2017

This paper presents a solution to the problem of specular meteor radar interferometry cast on the complex plane. This technique is applicable to all meteor radars at the output of the receiver's pulsed Doppler signal processing chain. Specular meteor trail radar echoes are modeled as exponentially decaying sinusoids impinging on a sparse interferometric antenna array. A set of 10 underdense meteor trail radar parameters are estimated using nonlinear least squares optimization of the physical model parameters. Meteor trail spatial locations are determined by estimating all parameters through global optimization of the complex‐valued interferometric angle‐of‐arrival equations. Statistical precision of the estimated meteor radar parameters of Doppler, diffusion coefficient, angle‐of‐arrival, and height are subsequently characterized by calculation of the full covariance matrix. The determination of statistical uncertainties in the measured parameters is a key innovation in the field, as it lays the groundwork for calculating the statistical precision of the subsequently derived wind field.
ABCA7 and risk of dementia and vascular disease in the Danish population
Authors: Kjeldsen Emilie W. , Tybjærg‐Hansen Anne , Nordestgaard Børge G. , Frikke‐Schmidt Ruth
Published: December 2017

Objective

ATP‐binding‐cassette transporter A7(ABCA7) is suggested to be involved in lipid transport as well as in phagocytosis of amyloid‐β in the brain. We tested the hypothesis that a common genetic variant in ABCA7 is associated with dementia, ischemic heart disease, ischemic cerebrovascular disease, and with lipid levels in the general population, independent of the common apolipoprotein E(APOE) genotype.

Methods

For this purpose, we genotyped a common genetic variant in ABCA7, identified in genome‐wide‐association‐studies of Alzheimer's disease, in 104,258 individuals from the Danish general population, and also meta‐analyzed our results with publicly available consortia data.

Results

Multifactorially adjusted hazard ratios for Alzheimer's disease were 1.07 (95% confidence interval:0.93–1.23) and 1.72 (1.24–2.40) for GA and AA versus GG genotype. Results were similar after APOE genotype adjustment and when only APOE ɛ33 carriers were studied. Including 178,304 individuals, the meta‐analyzed odds ratio for Alzheimer's disease per one allele ABCA7 rs4147929 increase was 1.15 (1.12–1.18). ABCA7 genotype was not convincingly associated with vascular dementia, ischemic heart disease, ischemic cerebrovascular disease, or with lipid levels. Including 288,563 individuals, meta‐analyzed odds ratios for ischemic heart disease per one allele ABCA7 rs4147929 increase was 1.01 (0.99–1.03).

Interpretation

A common genetic variant in ABCA7 was associated with high risk of Alzheimer's disease independent of APOE genotype. The lack of association with vascular dementia, ischemic heart disease, ischemic cerebrovascular disease, and with lipid levels suggests that ABCA7 is not important for atherosclerosis. Thus, our findings support the suggested role of ABCA7 in Alzheimer's disease pathology and phagocytic clearance of amyloid‐β in the brain.
Local Structure and Chemistry of C‐Doped ZnO@C Core–Shell Nanostructures with Room‐Temperature Ferromagnetism
Authors: Ngo Duc‐The , Cuong Le Thanh , Cuong Nguyen Huu , Son Cao Thai , Huy Pham Thanh , Dung Nguyen Duc
Published: December 2017

A superior approach is presented to study quantitatively fine structure of C‐doped ZnO nanostructure using transmission electron microscopy (TEM) from which the role of carbon in ZnO crystal to form ferromagnetism is revealed at the first time. Electron diffraction in TEM shows Wurtzite structure in the nanoparticles with lattice parameters (a = 0.327 ± 0.03 nm and c = 0.529 ± 0.04 nm) slightly different from the original structure. Interestingly, the Zn–C bonding with a bonding length of 2.58 Å is experimentally determined using atomic pair distribution function (PDF) calculated from electron diffraction data. Together with other bondings, such as C–C, Zn–O obtained from the PDF, this demonstrates migration of C atoms into ZnO crystal to substitute O vacancies. This is furthermore visualized by high‐resolution TEM imaging and elemental mapping, and strongly supports the proposal of origin of ferromagnetism in the C‐doped ZnO nanoparticles where the s–p and p–p hybridizations formed by C2p–Zn4s, and O2p–C2p orbitals are believed to cause ferromagnetism.
Novel Type‐II InAs/AlSb Core–Shell Nanowires and Their Enhanced Negative Photocurrent for Efficient Photodetection
Authors: Li Handong , Alradhi Hayfaa , Jin Zhiming , Anyebe Ezekiel A. , Sanchez Ana M. , Linhart Wojcioech M. , Kudrawiec Robert , Fang Hehai , Wang Zhiming , Hu Weida , Zhuang Qiandong
Published: December 2017

The control of optical and transport properties of semiconductor heterostructures is crucial for engineering new nanoscale photonic and electrical devices with diverse functions. Core–shell nanowires are evident examples of how tailoring the structure, i.e., the shell layer, plays a key role in the device performance. However, III–V semiconductors bandgap tuning has not yet been fully explored in nanowires. Here, a novel InAs/AlSb core–shell nanowire heterostructure is reported grown by molecular beam epitaxy and its application for room temperature infrared photodetection. The core–shell nanowires are dislocation‐free with small chemical intermixing at the interfaces. They also exhibit remarkable radiative emission efficiency, which is attributed to efficient surface passivation and quantum confinement induced by the shell. A high‐performance core–shell nanowire phototransistor is also demonstrated with negative photoresponse. In comparison with simple InAs nanowire phototransistor, the core–shell nanowire phototransistor has a dark current two orders of magnitude smaller and a sixfold improvement in photocurrent signal‐to‐noise ratio. The main factors for the improved photodetector performance are the surface passivation, the oxide in the AlSb shell and the type‐II bandgap alignment. The study demonstrates the potential of type‐II core–shell nanowires for the next generation of photodetectors on silicon.
Epitaxial Single‐Layer MoS2 on GaN with Enhanced Valley Helicity
Authors: Wan Yi , Xiao Jun , Li Jingzhen , Fang Xin , Zhang Kun , Fu Lei , Li Pan , Song Zhigang , Zhang Hui , Wang Yilun , Zhao Mervin , Lu Jing , Tang Ning , Ran Guangzhao , Zhang Xiang , Ye Yu , Dai Lun
Published: December 2017

Engineering the substrate of 2D transition metal dichalcogenides can couple the quasiparticle interaction between the 2D material and substrate, providing an additional route to realize conceptual quantum phenomena and novel device functionalities, such as realization of a 12‐time increased valley spitting in single‐layer WSe2 through the interfacial magnetic exchange field from a ferromagnetic EuS substrate, and band‐to‐band tunnel field‐effect transistors with a subthreshold swing below 60 mV dec−1 at room temperature based on bilayer n‐MoS2 and heavily doped p‐germanium, etc. Here, it is demonstrated that epitaxially grown single‐layer MoS2 on a lattice‐matched GaN substrate, possessing a type‐I band alignment, exhibits strong substrate‐induced interactions. The phonons in GaN quickly dissipate the energy of photogenerated carriers through electron–phonon interaction, resulting in a short exciton lifetime in the MoS2/GaN heterostructure. This interaction enables an enhanced valley helicity at room temperature (0.33 ± 0.05) observed in both steady‐state and time‐resolved circularly polarized photoluminescence measurements. The findings highlight the importance of substrate engineering for modulating the intrinsic valley carriers in ultrathin 2D materials and potentially open new paths for valleytronics and valley‐optoelectronic device applications.
Polyphenylnaphthalene as a Novel Building Block for High‐Performance Deep‐Blue Organic Light‐Emitting Devices
Authors: Chen Wen‐Cheng , Yuan Yi , Zhu Ze‐Lin , Jiang Zuo‐Quan , Liao Liang‐Sheng , Lee Chun‐Sing
Published: December 2017

A new member of polycyclic aromatic hydrocarbons named 1,2,3,4‐tetraphenylnaphthalene (TNa) is exploited and used as a potential building block in deep‐blue organic light‐emitting devices (OLEDs) for the first time. By incorporating TNa with phenanthroimidazole, three blue emitters named TNa‐PI, TNa‐BPI, and TNa‐DPI featuring different length of phenyl linkers are designed and synthesized via a facile approach, and systematically characterized with thermal, morphological, theoretical, photophysical, electrical, and electroluminescent (EL) studies. The new fluorophores show intramolecular charge transfer properties in excited state evidenced by positive solvatochromic effect in emission. Theoretical calculation suggests that TNa serves as an electron acceptor in the new molecules. All the new materials can emit intense deep‐blue fluorescence in thin film and show bipolar carrier transport properties, with electron conductivity much better than that of hole. Nondoped OLEDs based on TNa‐DPI exhibit excellent EL performance with a maximum external quantum efficiency (EQE) of 5.78% and deep‐blue emission with color purity of (0.152, 0.085). Furthermore, in the 30 wt.% doped device, TNa‐PI emits efficient violet‐blue EL with Commission Internationale de l'Èclarage coordinates of (0.156, 0.043) and shows a decent EQE of 2.52% at a practical brightness of 1000 cd m−2.
Enhanced Photodynamic Cancer Treatment by Mitochondria‐Targeting and Brominated Near‐Infrared Fluorophores
Authors: Noh Ilkoo , Lee DaeYong , Kim Heegon , Jeong Chan‐Uk , Lee Yunsoo , Ahn Jung‐Oh , Hyun Hoon , Park Ji‐Ho , Kim Yeu‐Chun
Published: December 2017

A noninvasive and selective therapy, photodynamic therapy (PDT) is widely researched in clinical fields; however, the lower efficiency of PDT can induce unexpected side effects. Mitochondria are extensively researched as target sites to maximize PDT effects because they play crucial roles in metabolism and can be used as cancer markers due to their high transmembrane potential. Here, a mitochondria targeting photodynamic therapeutic agent (MitDt) is developed. This photosensitizer is synthesized from heptamethine cyanine dyes, which are conjugated or modified as follows. The heptamethine meso‐position is conjugated with a triphenylphosphonium derivative for mitochondrial targeting, the N‐alkyl side chain is modified for regulation of charge balance and solubility, and the indolenine groups are brominated to enhance reactive oxygen species generation (ROS) after laser irradiation. The synthesized MitDt increases the cancer uptake efficiency due to the lipo‐cationic properties of the triphenylphosphonium, and the PDT effects of MitDt are amplified after laser irradiation because mitochondria are susceptible to ROS, the response to which triggers an apoptotic anticancer effect. Consequently, these hypotheses are demonstrated by in vitro and in vivo studies, and the results indicate strong potential for use of MitDts as efficient single‐molecule‐based PDT agents for cancer treatment.
Enantioselective Synthesis of the Cyclopiazonic Acid Family Using Sulfur Ylides
Authors: Zhurakovskyi Oleksandr , Türkmen Yunus E. , Löffler Lorenz E. , Moorthie Vijayalakshmi A. , Chen C. Chun , Shaw Michael A. , Crimmin Mark R. , Ferrara Marco , Ahmad Mushtaq , Ostovar Mehrnoosh , Matlock Johnathan V. , Aggarwal Varinder K.
Published: December 2017

A convergent, nine‐step (LLS), enantioselective synthesis of α‐cyclopiazonic acid and related natural products is reported. The route features a) an enantioselective aziridination of an imine with a chiral sulfur ylide; b) a bioinspired (3+2)‐cycloaddition of the aziridine onto an alkene; and c) installation of the acetyltetramic acid by an unprecedented tandem carbonylative lactamization/N−O cleavage of a bromoisoxazole.
Local influence diagnostics for hierarchical finite‐mixture random‐effects models
Authors: Rakhmawati Trias Wahyuni , Molenberghs Geert , Verbeke Geert , Faes Christel
Published: December 2017

The main objective of this paper is to evaluate the influence of individual subjects exerted on a random‐effects model for repeated measures, where the random effects follow a mixture distribution. The diagnostic tool is based on local influence with perturbation scheme that explicitly targets influences resulting from perturbing the mixture component probabilities. Bruckers, Molenberghs, Verbeke, and Geys (2016) considered a similar model, but focused on influences stemming from perturbing a subject's likelihood contributions as a whole. We also compare the two types of perturbation. Our results are illustrated using linear mixed models fitted to data from three studies. A simulation study is also conducted in order to strengthen the result from case studies.
Towards Sustainable Development in the Arab Middle East and North Africa Region: A Longitudinal Analysis of Environmental Disclosure in Corporate Annual Reports
Authors: Gerged Ali M , Cowton Christopher J , Beddewela Eshani S
Published: December 2017

This paper presents the first comprehensive analysis of corporate environmental disclosure in the Arab Middle East and North Africa region. Using a detailed research instrument containing 55 items, content analysis of the annual reports of 180 non‐financial companies listed on nine major stock markets was conducted over a 5‐year period. The calculation of an unweighted disclosure index indicates that, although the level of disclosure might be considered relatively low by international standards, it varies by country. Perhaps of greater significance for the future of sustainable development in the region, disclosure is shown to have increased significantly over the period 2010–2014. Further analysis shows that although there are some differences relating to categories of disclosure, this is a region‐wide phenomenon not driven by a subset of countries or types of company. This benchmark study provides a systematic picture for policy‐makers in the region and, for future researchers, both substantive findings and methodological insight. © 2017 The Authors.Business Strategy and the Environmentpublished by ERP Environment and John Wiley & Sons Ltd
Intramolecular Hydroamination by a Primary Amine of an Unactivated Alkene on Gold Nanoclusters: A DFT Study
Authors: Bobuatong Karan , Sakurai Hidehiro , Ehara Masahiro
Published: December 2017

The front cover artwork for issue 24/2017 is a collaboration between Institute for Molecular Science and Osaka University (Japan). The image shows that colloidal gold nanocluster catalyst performs intramolecular hydroamination by a primary amine of an unactivated alkene in anti‐addition mechanism. See the Full Paper itself at https://doi.org/10.1002/cctc.201700839.
A “Signal On” Photoelectrochemical Biosensor Based on Bismuth@N,O‐Codoped‐Carbon Core‐Shell Nanohybrids for Ultrasensitive Detection of Telomerase in HeLa Cells
Authors: Liu Shanshan , Zhao Shulin , Tu Wenwen , Wang Xiaoying , Wang Xiao , Bao Jianchun , Wang Yu , Han Min , Dai Zhihui
Published: December 2017

Core‐shell nanohybrids (NHs) with good semiconducting properties are vital to promote optoelectronic, photocatalytic, biosensing and bioelectronics technologies. Although great process has been achieved, synthesis of NHs composed of semiconductor core and heteroatom‐doped nanocarbon shell remains a challenge, and their applications in photoelectronchemical (PEC) biosensors have not been explored. Herein, the synthesis and properties of a Bi nanocrystal and N,O‐codoped carbon (NOC) core–shell NHs (Bi@NOC) is described, which exhibits the typical semiconducting feature with the bandgap of 1.14 eV. Also, such NHs show good biocompatibility and their surfaces bear the carboxylic groups that facilitate further assembly of an amino‐modified primer DNA. By taking advantage of the excellent PEC activity of Bi@NOC NHs and the signal amplification effect of thioflavine‐T, a novel “signal on” PEC aptasensor for the detection of telomerase activity is constructed. The fabricated aptasensor can detect telomerase activity from 5.0×102 to 1.0×106 HeLa cells with a low detection limit of 60 cells. Also, the aptasensor shows a wide linear response ranges, high sensitivity and good reproducibility. This work not only enriches current core–shell NHs family but also offers a novel PEC biosensing platform for detecting telomerase activity that is helpful for early clinical diagnosis of cancer.
Comparing Isomeric Tridentate Carbazole‐Based Click Ligands: Metal Complexes and Redox Chemistry
Authors: Pryjomska‐Ray Iweta , Zornik Denise , Pätzel Michael , Krause Konstantin B. , Grubert Lutz , Braun‐Cula Beatrice , Hecht Stefan , Limberg Christian
Published: December 2017

Two novel bis(triazolyl)carbazole ligands Hbtc1 (3,6‐di(tert‐butyl)‐1,8‐bis[(1‐(3,5‐di(tert‐butyl)phenyl)‐1,2,3‐triazol‐4‐yl)]‐9H‐carbazole) and Hbtc2 (3,6‐di(tert‐butyl)‐1,8‐bis[(4‐(3,5‐di(tert‐butyl)phenyl)‐1,2,3‐triazol‐1‐yl)]‐9H‐carbazole), differing in the regiochemistry of triazole attachment, have been synthesized by Cu‐catalyzed azide‐alkyne cycloaddition, the so‐called “click‐reactions”. Metalation with Ru, Zn, and Ni precursors led to the formation of M(btc)2 complexes (M=Ru, Zn, Ni), with two deprotonated ligands coordinating to the metal center in tridentate fashion, forming almost perfectly octahedral coordination spheres. The redox properties of M(btc)2 complexes have been investigated by cyclic voltammetry, UV/Vis spectroscopy, spectroelectrochemistry, and chemically. The CV of the ruthenium complexes revealed three quasi‐reversible one‐electron oxidation processes, one assigned as the RuII/III couple and two originating from ligand‐based oxidations. The CVs of both Zn and Ni complexes contained only two oxidation waves corresponding to the oxidation of the two ligands. The oxidation potentials of complexes derived from Hbtc1 ligands were found to be 300–400 mV lower than those of the corresponding complexes derived from Hbtc2, reflecting the significant difference in donation through the N(2) or N(3) atom of the triazole moiety.
Correlation between Ionic Liquid Cytotoxicity and Liposome–Ionic Liquid Interactions
Authors: Ruokonen Suvi‐Katriina , Sanwald Corinna , Robciuc Alexandra , Hietala Sami , Rantamäki Antti H. , Witos Joanna , King Alistair W. T. , Lämmerhofer Michael , Wiedmer Susanne K.
Published: December 2017

This study aims at extending the understanding of the toxicity mechanism of ionic liquids (ILs) using various analytical methods and cytotoxicity assays. The cytotoxicity of eight ILs and one zwitterionic compound was determined using mammalian and bacterial cells. The time dependency of the IL toxicity was assessed using human corneal epithelial cells. Hemolysis was performed using human red blood cells and the results were compared with destabilization data of synthetic liposomes upon addition of ILs. The effect of the ILs on the size and zeta potential of liposomes revealed information on changes in the lipid bilayer. Differential scanning calorimetry was used to study the penetration of the ILs into the lipid bilayer. Pulsed field gradient nuclear magnetic resonance spectroscopy was used to determine whether the ILs occurred as unimers, micelles, or if they were bound to liposomes. The results show that the investigated ILs can be divided into three groups based on the cytotoxicity mechanism: cell wall disrupting ILs, ILs exerting toxicity through both cell wall penetration and metabolic alteration, and ILs affecting solely on cell metabolism.
Sustainable Development through CSR in Human Resource Management Practices: The Effects of the Economic Crisis on Job Quality
Authors: Martínez‐Garcia Esther , Sorribes Joan , Celma Dolors
Published: December 2017

This article focuses on sustainable development and human resource management (HRM). It analyzes the effects of the economic crisis on corporate social responsibility (CSR) in the management of employees and its determinants, and also depicts a map of job quality for employees in Spain. Results show that the crisis has not changed the overall pattern or map; neither the characteristics of the firm, the employee, or the job that determine the map. Results also point to the fact that employees at the lower end of CSR in HRM practices have been the most affected by hard cost‐containment measures applied by firms, such as dismissals. Around one‐third of employees have low job quality in nearly all the dimensions analyzed; while two‐thirds have higher job quality, but with variability among dimensions. The analysis is conducted for the years 2006–2010, hence comprising pre‐crisis and amid the crisis years. Cross‐section repeated samples of employees are used, from the Quality of Working Life Survey, which allow us to study the evolution of HRM and CSR. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
Understanding Input and Output Legitimacy of Environmental Policymaking in The Gulf Cooperation Council States
Authors: Atalay Yasemin
Published: December 2017

This article analyses environmental policymaking in the Gulf Cooperation Council (GCC) states, with a focus on the output legitimacy of renewable energy uptake. Most environmental policy research so far has focused on either Western industrialized countries with established democracies or developing countries with either democratic or autocratic policymaking systems, and few studies have yet analyzed the overall effectiveness of these monarchies in environmental decisionmaking. The degree of this policy effectiveness is hence the focus of this paper. Specifically, the paper argues that, although there are a number of input legitimacy deficits in the six GCC countries (United Arab Emirates, Saudi Arabia, Qatar, Kuwait, Bahrain and Oman), there has been progress regarding renewable energy uptake. Thus, these monarchies may be relying more on output legitimacy than input legitimacy. Following up on the studies on input and output legitimacy, the main argument is that in certain cases useful policy results can be reached in the presence of not so strong input legitimacy, and other factors also have an impact on policymaking. The paper bases its analysis on an extensive study of primary and secondary sources, specifically institutional publications, international organization reports, newspaper articles and academic papers. With its analysis, the paper contributes to larger debates in environmental governance research on the relative effectiveness of renewable energy uptake in monarchical, resource‐rich, rentier states. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
Outcomes following heart failure hospitalization in a regional Australian setting between 2005 and 2014
Authors: Al‐Omary Mohammed S. , Khan Arshad A. , Davies Allan J. , Fletcher Peter J. , Mcivor Dawn , Bastian Bruce , Oldmeadow Christopher , Sverdlov Aaron L. , Attia John R. , Boyle Andrew J.
Published: December 2017

Aims

The aim of the current study is to examine 10 year trends in mortality and readmission following heart failure (HF) hospitalization in metropolitan and regional Australian settings.

Methods and results

We identified all index HF hospitalizations in the Hunter New England region from 2005 to 2014, using a 10 year ‘look back’ period. The primary endpoint was a composite of all‐cause mortality or all‐cause readmission at 1 year. Secondary endpoints included all‐cause mortality, all‐cause readmission, and HF readmission at 30 days and 1 year. We used logistic regression to explore the predictors of the composite outcome of either all‐cause death or readmission at 1 year. There were 12 114 patients admitted with a first episode of HF between 2005 and 2014, followed up until death or the end of 2015. The mean age was 78 ± 12 years and 49% (n = 5906) were male. A total of 4831 (40%) resided in regional areas and the remainder in metropolitan areas. One hundred sixty‐eight patients (1.4%) were Aboriginal. Approximately 69% of patients had either died or been readmitted for any cause within 12 months of their index event. The 30 day and 1 year all‐cause mortality rates were 13% and 32%, respectively, with no change in the trend over the study period. Age, socio‐economic disadvantage, ischaemic heart disease, renal failure, and chronic lower respiratory disease were predictors of the primary endpoint.

Conclusions

Heart failure hospitalizations are followed by high rates of death or readmission. There was no change in this composite endpoint over the 10 year study period.
Fabrication and Evaluation of Multi‐Walled Carbon Nanotubes Supported Novel Catalyst for Select Conversion of Cellulose to 5‐Hydroxymethylfurfural
Authors: Li Fei , Zhang Guang , Song Yinghua
Published: December 2017

Herein, a facile method for constructing acid‐base and CrIII species multi‐functionalized multi‐walled carbon nanotubes (CNTs) catalyst was reported. Acid and base, i.e., −SO3H and −NH2 groups, were first grafted on CNTs to synthesize CNTs−SO3H−NH2 bi‐functional catalyst. Then the obtained CNTs−SO3H−NH2 catalyst was further functionalized with CrIII species for further enhancement of acidity. The catalytic activity of fabricated catalysts were systematically studied for the one‐pot conversion of cellulose to 5‐hydroxymethylfurfural (HMF) in an ionic liquid solvent system. Results indicated that in the one‐pot cellulose to HMF reaction, acidic sites were necessary for dissolved cellulose hydrolysis and fructose dehydration process, and the isomerization of glucose to fructose can be regarded as rate determining step. Co‐existed base and Lewis acid sites were found to promote glucose isomerization to fructose, and Brønsted acid sites direct the dehydration of reactively formed fructose to HMF. And under the optimal conditions, the highest HMF yield of 40.2 % was achieved by multi‐functional CNTs−SO3H−NH2−CrIII catalyst. Moreover, the fabricated catalyst in this study revealed excellent stability for recycle use in HMF production from cellulose.
A Quasi 2D Flexible Micro‐Supercapacitor Based on MnO2//NiCo2O4 as a Miniaturized Energy‐Storage Device
Authors: Patil Swati J. , Park Jong Sung , Kim Young‐Bae , Lee Dong‐Weon
Published: December 2017

A miniaturized and flexible asymmetric micro‐supercapacitor (ASC) based on surface‐modified MnO2@Au and thin nanosheets of NiCo2O4@Au (termed 2D‐qMnO2//NiCo2O4 micro‐supercapacitor) is reported. A lightweight and superior flexible micro‐supercapacitor is successfully achieved using conventional microfabrication techniques. The proposed electrodeposition method is very effective for the surface modification and, as a result, uniform and high‐quality 2D‐quasi MnO2 and NiCo2O4 thin‐film formation on a collector current is achieved. The fabricated 2D‐qMnO2//NiCo2O4@Au and polymeric gel electrolyte‐based micro‐supercapacitor has advantageous features, with a high areal capacitance of 5.36 mF cm−2. The 2D‐qMnO2//NiCo2O4 MSC delivers a high energy density of 0.42 mWh cm−2 at 48.90 mW cm−2 power density with superior cycling stability (89.62 %) over initial 5000 cycles. Impedance analysis showed that the 2D‐qMnO2//NiCo2O4 MSC device has a phase angle of −73° with an extremely small relaxation time constant of 14 ms. Finally, excellent device performance of the 2D‐qMnO2//NiCo2O4 MSC under different bending and twisting is demonstrated to evaluate its mechanical flexibility.
Evaluation of chemical components in Citri Reticulatae Pericarpium of different cultivars collected from different regions by GC–MS and HPLC
Authors: Luo Meixia , Luo Hujie , Hu Pingjun , Yang Yiting , Wu Bo , Zheng Guodong
Published: December 2017

To discriminate the feasible differences and find potential similarities and relationships of Citri Reticulatae Pericarpium (CRP), this work was accomplished by a comprehensive and reliable method using gas chromatography–mass spectrometer (GC–MS) to analyze the volatile oils and high‐performance liquid chromatography (HPLC) simultaneously to determine the contents of five bioactive flavonoids, namely hesperidin, nobiletin, 3,5,6,7,8,3′,4′‐heptamethoxyflavone, tangeretin, and 5‐hydroxy‐6,7,8,3′,4′‐pentamethoxyflavone in 25 batches of CRP samples of 10 cultivars collected from different regions in China. The GC–MS analyses indicated that 98 compounds were successfully identified from the volatile oils obtained and the major constituents of volatile oil are d‐limonene, γ‐terpinene, α‐pinene, linalool, and myrcene. Even 2‐(methylamino) benzoate was found in all cultivar samples harvested at maturation stage. Under the optimal condition, the quantitative analyses of five bioactive flavonoids were successfully performed by HPLC and hierarchical cluster analysis (HCA). Results showed significant differences among cultivars in the contents of five bioactive flavonoids mentioned earlier. The HCA and GC–MS results provided a convenient approach which might be applied for rapid similarity evaluation and also holds the potential for analysis of compounds present in other plants. Therefore, this work obtained offers scientific basis to control quality and develop medicinal value of the medicinal materials in CRP.
Elemental, isotopic, and geochronological variability in Mogollon‐Datil volcanic province archaeological obsidian, southwestern USA: Solving issues of intersource discrimination
Authors: Shackley M. Steven , Morgan Leah , Pyle Douglas
Published: December 2017

Solving issues of intersource discrimination in archaeological obsidian is a recurring problem in geoarchaeological investigation, particularly since the number of known sources of archaeological obsidian worldwide has grown nearly exponentially in the last few decades, and the complexity of archaeological questions asked has grown equally so. These two parallel aspects of archaeological investigation have required more exacting understanding of the geological relationship between sources and the more accurate analysis of these sources of archaeological obsidian. This is particularly the case in the North American Southwest where the frequency of archaeological investigation is some of the highest in the world, and the theory and method used to interpret that record has become increasingly nuanced. Here, we attempt to unravel the elemental similarity of archaeological obsidian in the Mogollon‐Datil volcanic province of southwestern New Mexico where some of the most important and extensively distributed sources are located and the elemental similarity between the sources is great even though the distance between the sources is large. Uniting elemental, isotopic, and geochronological analyses as an intensive pilot study, we unpack this complexity to provide greater understanding of these important sources of archaeological obsidian.