bluuebunny/crossref_metadata_2025 huggingface dataset:
Bridging the connection between effective viscosity and electrical conductivity through water content in the upper mantle
Authors: Xu Yixian , Zhang Anqi , Yang Bo , Bao Xuewei , Wang Qinyan , Xia Jianghai , Yang Wencai
Published: January 2018

Upper mantle viscosity plays a key role in understanding plate tectonics and is usually extrapolated from laboratory-based creep measurements of upper mantle conditions or constrained by modeling geodetic and post-seismic observations. At present, an effective method to obtain a high-resolution viscosity structure is still lacking. Recently, a promising estimation of effective viscosity was obtained from a transform derived from the results of magnetotelluric imaging. Here, we build a relationship between effective viscosity and electrical conductivity in the upper mantle using water content. The contribution of water content to the effective viscosity is isolated in a flow law with reference to relatively dry conditions in the upper mantle. The proposed transform is robust and has been verified by application to data synthesized from an intraoceanic subduction zone model. We then apply the method to transform an electrical conductivity cross-section across the Yangtze block and the North China Craton. The results show that the effective viscosity structure coincides well with that estimated from other independent datasets at depths of 40 to 80 km but differs slightly at depths of 100 to 200 km. We briefly discussed the potentials and associated problems for application.
Current distribution across type II superconducting films: a new vortex-free critical state
Authors: Talantsev E. F. , Pantoja A. E. , Crump W. P. , Tallon J. L.
Published: January 2018

The current distribution across the thickness of a current-carrying rectangular film in the Meissner state was established long ago by the London brothers. The distribution across the width is more complicated but was later shown to be highly non-uniform, diverging at the edges. Accordingly, the standard view for type II superconductors is that vortices enter at the edges and, with increasing current, are driven inwards until they self-annihilate at the centre, causing dissipation. This condition is presumed to define the critical current. However we have shown that, under self-field (no external field), the transport critical current is a London surface current where the surface current density equals the critical field divided by λ, across the entire width. The critical current distribution must therefore be uniform. Here we report studies of the current and field distribution across commercial YBa2Cu3 O7 conductors and confirm the accepted non-uniform distribution at low current but demonstrate a radical crossover to a uniform distribution at critical current. This crossover ends discontinuously at a singularity and calculations quantitatively confirm these results in detail. The onset of self-field dissipation is, unexpectedly, thermodynamic in character and the implied vortex-free critical state seems to require new physics.
A regional assessment of cumulative impact mapping on Mediterranean coralligenous outcrops
Authors: Bevilacqua S. , Guarnieri G. , Farella G. , Terlizzi A. , Fraschetti S.
Published: January 2018

In the last decade, the ‘Cumulative Pressure and Impact Assessment’ (CPIA) approach emerged as a tool to map expected impacts on marine ecosystems. However, CPIA assumes a linear response of ecosystems to increasing level of cumulative pressure weighting sensitivity to different anthropogenic pressures through expert judgement. We applied CPIA to Mediterranean coralligenous outcrops over 1000 km of the Italian coastline. Extensive field surveys were conducted to assess the actual condition of coralligenous assemblages at varying levels of human pressure. As pressure increased, a clear shift from bioconstructors to turf-dominated assemblages was found. The linear model originally assumed for CPIA did not fit the actual relationship between expected cumulative impact versus assemblage degradation. A log-log model, instead, best fitted the data and predicted a different map of cumulative impact in the study area able to appreciate the whole range of impact scenarios. Hence, the relative importance of different drivers in explaining the observed pattern of degradation was not aligned with weights from the expert opinion. Such findings stress the need for more incisive efforts to collect empirical evidence on ecosystem-specific responses to human pressure in order to refine CPIA predictions.
pH-Mediated molecular differentiation for fluorimetric quantification of chemotherapeutic drugs in human plasma
Authors: Serrano Luis A. , Yang Ye , Salvati Elisa , Stellacci Francesco , Krol Silke , Guldin Stefan
Published: January 2018

We present a simple and effective route for reliable differentiation and quantification of target compounds in complex media based on a deprotonation-related bathochromic shift.
Controllable assembly of the benzothiazole framework using a CC triple bond as a one-carbon synthon
Authors: Huang Yubing , Yan Donghao , Wang Xu , Zhou Peiqi , Wu Wanqing , Jiang Huanfeng
Published: January 2018

A one-pot protocol to controllably assemble diverse benzothiazole derivatives from o-haloanilines, elemental sulfur and terminal alkynes has been realized.
Secondary relaxation in ultrastable etoricoxib: evidence of correlation with structural relaxation
Authors: Rodríguez-Tinoco Cristian , Rams-Baron Marzena , Ngai K. L. , Jurkiewicz Karolina , Rodríguez-Viejo Javier , Paluch Marian
Published: January 2018

We show an unprecedented connection between secondary and structural relaxations in ultrastable etoricoxib in exactly the same manner as in the ordinary glass, manifested through different properties, such as aging and devitrification.
The reactivity of cyclopropyl cyanide in titan's atmosphere: a possible pre-biotic mechanism
Authors: López E. , Ascenzi D. , Tosi P. , Bofill J. M. , de Andrés J. , Albertí M. , Lucas J. M. , Aguilar A.
Published: January 2018

Formation of possible highly reactive prebiotic molecules from protonated and non-protonated cyclopropyl cyanide species.
Cyclic trimers of phosphinic acids in polar aprotic solvent: symmetry, chirality and H/D isotope effects on NMR chemical shifts
Authors: Mulloyarova V. V. , Giba I. S. , Kostin M. A. , Denisov G. S. , Shenderovich I. G. , Tolstoy P. M.
Published: January 2018

By using NMR in liquefied gases, the stoichiometry of hydrogen-bonded complexes is determinedviaH/D isotope effects on proton chemical shifts.
Mechanochemical methods for the preparation of intercalation compounds, from intercalation to the formation of layered double hydroxides
Authors: Intasa-ard Soontaree (Grace) , Imwiset Kamonnart (Jaa) , Bureekaew Sareeya , Ogawa Makoto
Published: January 2018

Mechanochemical methods (solid–solid reactions under ambient conditions or solvent free synthesis) are useful for the preparation of intercalation compounds.
An unprecedented nanocage-like and heterometallic [MoIV3O4]-polyoxomolybdate hybrid
Authors: Xu Xian , Luo Ben-long , Wang Lu-Lu , Xu Li
Published: January 2018

A general synthetic route toward [MoIV3O4]-POMs is established to yield the first Mo4+–Mo5+–Mo6+ nanocage cluster, Na[(MoIV3O4)4MoV4MoVI3O27(OH)Py12] (1) and the first heterometallic hybrid, H2[(MoIV3O4)MoVI10Zn(PO4)4(OH)2O27py3] (2) (Mo4+, pink; Mo5+, green; Mo6+, black green; P, yellow; Zn, aqua.
Candida albicanszincophore and zinc transporter interactions with Zn(ii) and Ni(ii)
Authors: Łoboda D. , Rowińska-Żyrek M.
Published: January 2018

The Zrt1 transporter binds Zn(ii) with higher affinity than the Pra1 zincophore, allowing efficient zinc transfer into the fungal cell.
Responses of deposition and bioaccumulation in the Great Lakes region to policy and other large-scale drivers of mercury emissions
Authors: Perlinger J. A. , Urban N. R. , Giang A. , Selin N. E. , Hendricks A. N. , Zhang H. , Kumar A. , Wu S. , Gagnon V. S. , Gorman H. S. , Norman E. S.
Published: January 2018

The effect of policy on fish mercury levels varies spatially, even within the Great Lakes Basin.
CO adsorption and oxygen activation on group 11 nanoparticles – a combined DFT and high level CCSD(T) study about size effects and activation processes
Authors: Dononelli Wilke , Klüner Thorsten
Published: January 2018

The focus of this study lies in the activation of molecular oxygen and reaction with CO within density functional theory (DFT) and high level CCSD(T) calculations.
Cellulose–hemicellulose interactions at elevated temperatures increase cellulose recalcitrance to biological conversion
Authors: Kumar Rajeev , Bhagia Samarthya , Smith Micholas Dean , Petridis Loukas , Ong Rebecca G. , Cai Charles M. , Mittal Ashutosh , Himmel Michael H. , Balan Venkatesh , Dale Bruce E. , Ragauskas Arthur J. , Smith Jeremy C. , Wyman Charles E.
Published: January 2018

Hemicellulose–cellulose strong associations at elevated temperatures slows cellulose conversion significantly.
A diketopyrrolopyrrole-based fluorescent probe for investigating mitochondrial zinc ions
Authors: Du Chenchen , Fu Shibo , Ren Xiaolei , Wang Xiaohua , Wang Zhong , Zhou Juan , Wang Hongyu
Published: January 2018

We report a diketopyrrolopyrrole-based fluorescent probe DPP-Mito, which is low toxicity and mitochondrial-specific localization and could monitor the changes in the intracellular Zn2+ concentrations.
Palladium nanoparticles induce autophagy and autophagic flux blockade in Hela cells
Authors: Zhang Li , Chen Xuerui , Wu Jianzhou , Ding Shiping , Wang Xu , Lei Qunfang , Fang Wenjun
Published: January 2018

Size-dependent autophagy and autophagic flux blockade in Hela cells by palladium nanoparticles.
Synthesis of boron nitride nanotubes using an oxygen and carbon dual-free precursor
Authors: Abbas Saleem , Abbas Aumber , Huang Yang , Lin Jing , Liu Zhenya , Fang Yi , Tang Chengchun
Published: January 2018

Boron nitride nanotubes (BNNTs) have attracted extensive research attention due to their intriguing properties and promising applications.
Generation of controllable gaseous H2S concentrations using microfluidics
Authors: Christoforidis Theodore , Driver Tom G. , Rehman Jalees , Eddington David T.
Published: January 2018

Hydrogen sulfide (H2S) plays an important role as an intracellular signaling molecule, but is difficult to control in vitro. This paper presents a simple way to generate stable H2S conditions via microfluidic networks.
Prediction of microRNA–disease associations with a Kronecker kernel matrix dimension reduction model
Authors: Li Guanghui , Luo Jiawei , Xiao Qiu , Liang Cheng , Ding Pingjian
Published: January 2018

A Kronecker kernel matrix dimension reduction model for predicting novel miRNA–disease associations.
Characterization of magnetic relaxation when biofunctionalized magnetic nano-particles are associated with biomarkers in the liquid state in biomedical applications
Authors: Liao Shu-Hsien , Huang Han-Sheng , Chen Jean-Hong , Su Yu-Kai , Tong Yuan-Fu
Published: January 2018

This study determined the characteristics of the time-dependent effective relaxation time τeff and magnetization M when biofunctionalized magnetic nanoparticles (BMNPs) associated with biomarkers in a liquid immunoassay.
Can water continuously oxidize the PuO molecule? Mechanisms, topological analysis and rate constant calculations
Authors: Niu Wenxia , Xie Feng , Li Peng , Ma Jie , Gao Tao , Yin Huaqiang
Published: January 2018

A detailed description of the PuO continuously oxidized by water in the gas-phase.
Predictive and mechanistic multivariate linear regression models for reaction development
Authors: Santiago Celine B. , Guo Jing-Yao , Sigman Matthew S.
Published: January 2018

The utilization of physical organic molecular descriptors for the quantitative description of reaction outcomes in multivariate linear regression models is demonstrated as an effective tool fora prioriprediction and mechanistic interrogation.
Coupling of sterically demanding peptides by β-thiolactone-mediated native chemical ligation
Authors: Chen Huan , Xiao Yunxian , Yuan Ning , Weng Jiaping , Gao Pengcheng , Breindel Leonard , Shekhtman Alexander , Zhang Qiang
Published: January 2018

β-Thiolactones have enabled the sterically demanding peptidyl ligations of Val–Leu, Val–Val and Val–Pro using a one-pot NCL and desulfurization protocol.
In situ synchrotron radiation X-ray diffraction studies on molecular aggregation structure of nylon 12 films during bulge testing
Authors: Kojio Ken , Nagano Chigusa , Fujimoto Aya , Nozaki Shuhei , Yokomachi Kazutoshi , Kamitani Kazutaka , Watanabe Hirohmi , Takahara Atsushi
Published: January 2018

It is desirable to establish a method for evaluating mechanical properties, such as modulus and strength, of micrometer and sub-micrometer thick polymer films.
Solid-phase nucleation free-energy barriers in truncated cubes: interplay of localized orientational order and facet alignment
Authors: Sharma Abhishek K. , Thapar Vikram , Escobedo Fernando A.
Published: January 2018

The nucleation of ordered phases from the bulk isotropic phase of octahedron-like particles has been studied via Monte Carlo simulations and umbrella sampling.
Tough, adhesive and self-healing conductive 3D network hydrogel of physically linked functionalized-boron nitride/clay /poly(N-isopropylacrylamide)
Authors: Tong Xin , Du Lina , Xu Qun
Published: January 2018

A multi-functional delicate conductive nanostructure of a 3D hierarchical physically linked f-BNNS/clay/PNIPAM hydrogel has been fabricated successfully.
ROS-responsive capsules engineered from green tea polyphenol–metal networks for anticancer drug delivery
Authors: Wang Xiaoli , Li Xuanling , Liang Xiaoyu , Liang Jiayi , Zhang Chao , Yang Jing , Wang Chun , Kong Deling , Sun Hongfan
Published: January 2018

Reactive oxygen species (ROS)-responsive nanocapsules for cancer drug delivery were engineered from green tea polyphenol–metal networks.
Luminescence enhancement of CaF2:Nd3+nanoparticles in the second near-infrared window forin vivoimaging through Y3+doping
Authors: Yu Zhen-feng , Shi Jun-peng , Li Jin-lei , Li Peng-hui , Zhang Hong-wu
Published: January 2018

In vivoluminescent imaging in the second biological window (1000–1400 nm, NIR-II) has attracted increasing attention since it can provide high sensitivity to deep tissuein vivoimaging.
The design of smectic liquid crystals with an axially chiral biphenyl core: in search of a proper ferroelectric liquid crystal phase
Authors: Ahmed Ziauddin , Müller Carsten , Holzwarth Marcel , Haege Christian , Giesselmann Frank , Lemieux Robert P.
Published: January 2018

A tricarbosilane-terminated mesogen with an axially chiral biphenyl core forms a ferroelectric liquid crystal phase.
Correction: Enhanced photocatalytic activity of TiO2–Cu/C with regulation and matching of energy levels by carbon and copper for photoreduction of CO2 into CH4
Authors: Yan Yabin , Yu Yanlong , Cao Chi , Huang Shaolong , Yang Yajun , Yang Xiaodan , Cao Yaan
Published: January 2018

Correction for ‘Enhanced photocatalytic activity of TiO2–Cu/C with regulation and matching of energy levels by carbon and copper for photoreduction of CO2 into CH4’ by Yabin Yan et al., CrystEngComm, 2016, 18, 2956–2964.
Correction: Planar vs. three-dimensional X62−, X2Y42−, and X3Y32− (X, Y = B, Al, Ga) metal clusters: an analysis of their relative energies through the turn-upside-down approach
Authors: El Bakouri Ouissam , Solà Miquel , Poater Jordi
Published: January 2018

Correction for ‘Planar vs. three-dimensional X62−, X2Y42−, and X3Y32− (X, Y = B, Al, Ga) metal clusters: an analysis of their relative energies through the turn-upside-down approach by Ouissam El Bakouri et al., Phys. Chem. Chem. Phys., 2016, 18, 21102–21110.
CMS-G from Beta vulgaris ssp. maritima is maintained in natural populations despite containing an atypical cytochrome c oxidase
Authors: Meyer Etienne H. , Lehmann Caroline , Boivin Stéphane , Brings Lea , De Cauwer Isabelle , Bock Ralph , Kühn Kristina , Touzet Pascal
Published: January 2018

While mitochondrial mutants of the respiratory machinery are rare and often lethal, cytoplasmic male sterility (CMS), a mitochondrially inherited trait that results in pollen abortion, is frequently encountered in wild populations. It generates a breeding system called gynodioecy. In Beta vulgaris ssp. maritima, a gynodioecious species, we found CMS-G to be widespread across the distribution range of the species. Despite the sequencing of the mitochondrial genome of CMS-G, the mitochondrial sterilizing factor causing CMS-G is still unknown. By characterizing biochemically CMS-G, we found that the expression of several mitochondrial proteins is altered in CMS-G plants. In particular, Cox1, a core subunit of the cytochrome c oxidase (complex IV), is larger but can still assemble into complex IV. However, the CMS-G-specific complex IV was only detected as a stabilized dimer. We did not observe any alteration of the affinity of complex IV for cytochrome c; however, in CMS-G, complex IV capacity is reduced. Our results show that CMS-G is maintained in many natural populations despite being associated with an atypical complex IV. We suggest that the modified complex IV could incur the associated cost predicted by theoretical models to maintain gynodioecy in wild populations.
The roles of interleukins in perfusion recovery after peripheral arterial disease
Authors: Chen Lingdan , Liu Hanwei , Yuan Mingjie , Lu Wenju , Wang Jian , Wang Tao
Published: January 2018

In peripheral arterial disease (PAD) patients, occlusions in the major arteries that supply the leg makes blood flow dependent on the capacity of neovascularization. There is no current medication that is able to increase neovascularization to the ischemic limb and directly treat the primary problem of PAD. An increasing body of evidence supports the notion that inflammation plays an important role in the vascular remodeling and perfusion recovery after PAD. Interleukins (ILs), a group of proteins produced during inflammation, have been considered to be important for angiogenesis and arteriogenesis after tissue ischemia. This review summarizes the latest clinical and experimental developments of the role of ILs in blood perfusion recovery after PAD.
Biomedical compound figure detection using deep learning and fusion techniques
Authors: Lee Sheng Long , Zare Mohammad Reza
Published: January 2018

Images contain significant amounts of information but present different challenges relative to textual information. One such challenge is compound figures or images made up of two or more subfigures. A deep learning model is proposed for compound figure detection (CFD) in the biomedical article domain. First, pre‐trained convolutional neural networks (CNNs) are selected for transfer learning to take advantage of the image classification performance of CNNs and to overcome the limited dataset of the CFD problem. Next, the pre‐trained CNNs are fine‐tuned on the training data with early‐stopping to avoid overfitting. Alternatively, layer activations of the pre‐trained CNNs are extracted and used as input features to a support vector machine classifier. Finally, individual model outputs are combined with score‐based fusion. The proposed combined model obtained a best test accuracy of 90.03 and 96.93% outperforming traditional hand‐crafted and other deep learning representations on the ImageCLEF 2015 and 2016 CFD subtask datasets, respectively, by using AlexNet, VGG‐16, VGG‐19 pre‐trained CNNs fine‐tuned until best validation accuracy stops increasing combined with the combPROD score‐based fusion operator.
Preparation and thermoelectric properties of PANI matrix graphene composite material
Authors: Wang Dengwu , Xu Qian , Hu Bo , Ma Sude
Published: January 2018

Enormous amounts of unused waste heat have created a strong demand for high‐efficient heat‐to‐electric generators, so thermoelectric (TE) material (i.e. a kind of semiconductor which can generate electricity from a temperature difference) has become increasingly important. However, the inorganic TE materials are expensive, scarce reserves in the earth crust, poisonous and hard to be processed, so the research and development of organic TE materials are very urgent. The polyaniline (PANI, i.e. one of the conducting polymer) and PANI matrix graphene composite material were prepared. The chemical structure, microstructure and properties were investigated by Fourier transformer infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, and TE properties measurement system. Results showed that the distribution of the molecule chains in PANI were irregular, however, graphene worked as an interconnected network in the composite materials when 20 wt% graphene was added. Power factor, electrical and thermal conductivities of the composite material increased greatly while ZT (i.e. the figure of merit) of which was two times of PANI. The addition of graphene was an effective method to increase the TE properties of PANI.
The Penn State - Toruń Centre for Astronomy Planet Search stars
Authors: Deka-Szymankiewicz B. , Niedzielski A. , Adamczyk M. , Adamów M. , Nowak G. , Wolszczan A.
Published: January 2018

Context. Our knowledge of the intrinsic parameters of exoplanets is as precise as our determinations of their stellar hosts parameters. In the case of radial velocity searches for planets, stellar masses appear to be crucial. But before estimating stellar masses properly, detailed spectroscopic analysis is essential. With this paper we conclude a general spectroscopic description of the Pennsylvania-Toruń Planet Search (PTPS) sample of stars.

Aims. We aim at a detailed description of basic parameters of stars representing the complete PTPS sample. We present atmospheric and physical parameters for dwarf stars observed within the PTPS along with updated physical parameters for the remaining stars from this sample after the first Gaia data release.

Methods. We used high resolution (R = 60 000) and high signal-to-noise-ratio (S/N = 150–250) spectra from the Hobby-Eberly Telescope and its High Resolution Spectrograph. Stellar atmospheric parameters were determined through a strictly spectroscopic local thermodynamic equilibrium analysis (LTE) of the equivalent widths of Fe I and Fe II lines. Stellar masses, ages, and luminosities were estimated through a Bayesian analysis of theoretical isochrones.

Results. We present Teff, log g, [Fe/H], microturbulence velocities, absolute radial velocities, and rotational velocities for 156 stars from the dwarf sample of PTPS. For most of these stars these are the first determinations. We refine the definition of PTPS subsamples of stars (giants, subgiants, and dwarfs) and update the luminosity classes for all PTPS stars. Using available Gaia and HIPPARCOS parallaxes, we redetermine the stellar parameters (masses, radii, luminosities, and ages) for 451 PTPS stars.

Conclusions. The complete PTPS sample of 885 stars is composed of 132 dwarfs, 238 subgiants, and 515 giants, of which the vast majority are of roughly solar mass; however, 114 have masses higher than 1.5 M⊙ and 30 of over 2 M⊙. The PTPS extends toward much less metal abundant and much more distant stars than other planet search projects aimed at detecting planets around evolved stars; 29% of our targets belong to the Galactic thick disc and 2% belong to the halo.
A NuSTAR census of coronal parameters in Seyfert galaxies
Authors: Tortosa A. , Bianchi S. , Marinucci A. , Matt G. , Petrucci P. O.
Published: January 2018

Context. We discuss the results of the hot corona parameters of active galactic nuclei (AGN) that have been recently measured with NuSTAR. The values taken from the literature of a sample of 19 bright Seyfert galaxies are analysed.

Aims. The aim of this work is to look for correlations between coronal parameters, such as the photon index and cut-off energy (when a phenomenological model is adopted) or the optical depth and temperature (when a Comptonization model is used), and other parameters of the systems, such as the black hole mass or the Eddington ratio.

Methods. We analysed the coronal parameters of the 19 unobscured, bright Seyfert galaxies that are present in the Swift/BAT 70-month catalogue and that have been observed by NuSTAR, alone or simultaneously with others X-ray observatories, such as Swift, Suzaku, or XMM-Newton.

Results. We found an anti-correlation with a significance level >98% between the coronal optical depth and the coronal temperature of our sample. On the other hand, no correlation between the above parameters and the black hole mass, the accretion rate, and the intrinsic spectral slope of the sources is found.
Properties and rotation of molecular clouds in M 33
Authors: Braine J. , Rosolowsky E. , Gratier P. , Corbelli E. , Schuster K.-F.
Published: January 2018

The sample of 566 molecular clouds identified in the CO(2–1) IRAM survey covering the disk of M 33 is explored in detail. The clouds were found using CPROPS and were subsequently catalogued in terms of their star-forming properties as non-star-forming (A), with embedded star formation (B), or with exposed star formation (C, e.g., presence of Hα emission). We find that the size-linewidth relation among the M 33 clouds is quite weak but, when comparing with clouds in other nearby galaxies, the linewidth scales with average metallicity. The linewidth and particularly the line brightness decrease with galactocentric distance. The large number of clouds makes it possible to calculate well-sampled cloud mass spectra and mass spectra of subsamples. As noted earlier, but considerably better defined here, the mass spectrum steepens (i.e., higher fraction of small clouds) with galactocentric distance. A new finding is that the mass spectrum of A clouds is much steeper than that of the star-forming clouds. Further dividing the sample, this difference is strong at both large and small galactocentric distances and the A vs. C difference is a stronger effect than the inner vs. outer disk difference in mass spectra. Velocity gradients are identified in the clouds using standard techniques. The gradients are weak and are dominated by prograde rotation; the effect is stronger for the high signal-to-noise clouds. A discussion of the uncertainties is presented. The angular momenta are low but compatible with at least some simulations. Finally, the cloud velocity gradients are compared with the gradient of disk rotation. The cloud and galactic gradients are similar; the cloud rotation periods are much longer than cloud lifetimes and comparable to the galactic rotation period. The rotational kinetic energy is 1–2% of the gravitational potential energy and the cloud edge velocity is well below the escape velocity, such that cloud-scale rotation probably has little influence on the evolution of molecular clouds.
Les oasis en Afrique du Nord : dynamiques territoriales et durabilité des systèmes de production agricole
Authors: Bouaziz Ahmed , Hammani Ali , Kuper Marcel
Published: January 2018

Les oasis sahariennes ont connu des changements particulièrement profonds et déstabilisants dans la seconde moitié du 20e siècle, s’accompagnant de transformations sociales, économiques, agricoles et environnementales. Aux oasis phoenicicoles étagées classiques, viennent s’adjoindre de nouvelles extensions ou projets agricoles à travers des initiatives étatiques ou locales. Dans un contexte où les formes d’agriculture les plus modernes et les plus traditionnelles sont juxtaposées, il est pertinent d’analyser à la fois les ruptures et les continuités entre ces différentes formes d’agriculture saharienne. C’est précisément dans le but de contribuer à améliorer et partager les connaissances sur les dynamiques agricoles et territoriales en cours dans les oasis en Afrique du Nord, que nous avons organisé un symposium international à Zagora, oasis de peuplement millénaire. Le présent numéro thématique prolonge cette discussion sur ces dynamiques au sein des anciennes et nouvelles oasis et leurs interrelations avec les modes d’élevage et les activités non agricoles. Les différentes contributions au numéro thématique montrent les risques induits par les changements rapides. Elles dévoilent aussi des oasis bien vivantes, dont la durabilité passe sans doute par la cohabitation d’initiatives diversifiées.
Synthesis of Alkoxycarbonyldifluoromethyl-Substituted Semisquarates and Their Transformations
Authors: Yamamoto Yoshihiko , Kurohara Takashi , Jiyue Jiang , Shibuya Masatoshi
Published: January 2018

A novel EtO2CCF2-substituted semisquarate is synthesized from diisopropyl squarate by selective 1,2-addition of the Reformatsky reagent derived from BrCF2CO2Et and subsequent rhenium-catalyzed allylic alcohol rearrangement. The compatibility of the highly reactive EtO2CCF2 group in ring transformations of the obtained semisquarate is investigated. Various EtO2CCF2-substituted, highly functionalized compounds, such as quinones, tetronates, cyclopentenones and a bicyclo-[3.2.0]heptenone, are successfully synthesized by ring transformations of the EtO2CCF2-substituted semisquarate. Also, an allylO2CCF2-substituted semisquarate is prepared and converted into the corresponding tetronate. Subsequent palladium-catalyzed deallylation followed by condensation of the resulting carboxylic acid with several amines under mild conditions affords the corresponding α,α-difluoroamides in good yields.
Impaired Recognition of Emotional Faces after Stroke Involving Right Amygdala or Insula
Authors: Godin Brittany , Oishi Kumiko , Oishi Kenichi , Davis Cameron , Gomez Yessenia , Trupe Lydia , Kim Eun , Hillis Argye , Tippett Donna
Published: January 2018

Despite its basic and translational importance, the neural circuitry supporting the perception of emotional faces remains incompletely understood. Functional imaging studies and chronic lesion studies indicate distinct roles of the amygdala and insula in recognition of fear and disgust in facial expressions, whereas intracranial encephalography studies, which are not encumbered by variations in human anatomy, indicate a somewhat different role of these structures. In this article, we leveraged lesion-mapping techniques in individuals with acute right hemisphere stroke to investigate lesions associated with impaired recognition of prototypic emotional faces before significant neural reorganization can occur during recovery from stroke. Right hemisphere stroke patients were significantly less accurate than controls on a test of emotional facial recognition for both positive and negative emotions. Patients with right amygdala or anterior insula lesions had significantly lower scores than other right hemisphere stroke patients on recognition of angry and happy faces. Lesion volume within several regions, including the right amygdala and anterior insula, each independently contributed to the error rate in recognition of individual emotions. Results provide additional support for a necessary role of the right amygdala and anterior insula within a network of regions underlying recognition of facial expressions, particularly those that have biological importance or motivational relevance and have implications for clinical practice.
Lung Adenocarcinoma Invasiveness Risk in Pure Ground-Glass Opacity Lung Nodules Smaller than 2 cm
Authors: Lee Geun Dong , Park Chul Hwan , Park Heae Surng , Byun Min Kwang , Lee Ik Jae , Kim Tae Hoon , Lee Sungsoo
Published: January 2018

Background We aimed to identify clinicopathologic characteristics and risk of invasiveness of lung adenocarcinoma in surgically resected pure ground-glass opacity lung nodules (GGNs) smaller than 2 cm.

Methods Among 755 operations for lung cancer or tumors suspicious for lung cancer performed from 2012 to 2016, we retrospectively analyzed 44 surgically resected pure GGNs smaller than 2 cm in diameter on computed tomography (CT).

Results The study group was composed of 36 patients including 11 men and 25 women with a median age of 59.5 years (range, 34–77). Median follow-up duration of pure GGNs was 6 months (range, 0–63). Median maximum diameter of pure GGNs was 8.5 mm (range, 4–19). Pure GGNs were resected by wedge resection, segmentectomy, or lobectomy in 27 (61.4%), 10 (22.7%), and 7 (15.9%) cases, respectively. Pathologic diagnosis was atypical adenomatous hyperplasia, adenocarcinoma in situ, minimally invasive adenocarcinoma (MIA), or invasive adenocarcinoma (IA) in 1 (2.3%), 18 (40.9%), 15 (34.1%), and 10 (22.7%) cases, respectively. The optimal cutoff value for CT-maximal diameter to predict MIA or IA was 9.1 mm. In multivariate analyses, maximal CT-maximal diameter of GGNs ≥10 mm (odds ratio, 24.050; 95% confidence interval, 2.6–221.908; p = 0.005) emerged as significant independent predictor for either MIA or IA. Estimated risks of MIA or IA were 37.2, 59.3, 78.2, and 89.8% at maximal GGN diameters of 5, 10, 15, and 20 mm, respectively.

Conclusion Pure GGNs were highly associated with lung adenocarcinoma in surgically resected cases, while estimated risk of GGNs invasiveness gradually increased as maximal diameter increased.
Keloidbehandlung mit intraläsionaler Kryochirurgie
Authors: Zouboulis C. , Weidmann M. , Har-Shai Y.
Published: January 2018

Die Überproduktion veränderter Kollagenfasern und die Überexpression von Tumor-Growth-Factor-β muss gehemmt werden, um den Wachstumsprozess innerhalb einer Keloidnarbe zu unterbrechen. Dies kann mit den klassischen Therapieverfahren kaum gelingen. Die Behandlungsergebnisse der Keloidtherapie sind nur schwer vorherzusagen und die Rezidivrate liegt meist über 50 %. Darüber hinaus können einige der eingesetzten Verfahren (z. B. Bestrahlung) zusätzliche gesundheitliche Risiken verursachen. Die intraläsionale Kryochirurgie bietet eine seit nunmehr 10 Jahren erprobte Therapiealternative an. Eigene Ergebnisse von weit über tausend Behandlungen von Patienten mit Keloiden ermöglichen eine kritische Analyse, um eine Unterscheidung der Keloide, die gut zu behandeln sind, von denen, die sich für eine Behandlung weniger oder gar nicht eignen, treffen zu können.
Effect of finger geometries on strain response of interdigitated capacitor based soft strain sensors
Authors: Shin Hee-Sup , Bergbreiter Sarah
Published: January 2018

The finger geometry of embedded elastomeric comb capacitors significantly affects the electromechanical response of interdigitated capacitor (IDC) based soft sensors. When strain is applied to these IDC based soft sensors, the embedded soft combs are deformed, changing the sensor's capacitance to detect a variety of different mechanical loads. To better understand the effect of design parameters on sensor sensitivity, a comprehensive closed-form analytical model using geometric stretch and a parallel plate capacitance model in combination with a coplanar waveguide model to predict the strain response as a function of finger geometry and load orientation were developed. To validate this model, we compare the predicted response with computational and experimental methods using sensors with a combination of two different finger thicknesses and widths in a 4 mm2 area. Strong agreement was shown in all three results from the analytical model, the finite element analysis simulations, and the experiments validating that the sensitivity of IDC soft strain sensors can be tuned by finger geometry.
Pedestals and feedback in fusion-plasma relevant sandpile models
Authors: Bowie C. A. , Hole M. J.
Published: January 2018

We present modifications to the sandpile model [Chapman, Phys. Rev. E 62, 1905 (2000)] (Classic Model). A feedback loop is added to the Classic Model, elements of which may have relevance to the behaviour of a fusion plasma. Those elements include variation of the total energy of the system in proportion to a proxy for the Larmor radius, ρ, and resulting variations in mass loss event (MLE) size and waiting times between MLEs. We also show other variants of the Classic Model which produce pedestals, without introducing feedback. The modifications produce a pedestal similar to that seen in a fusion plasma, as well as feedback effects. We observe that maximum MLE sizes, and maximum waiting times between MLEs, grow with pedestal size only in the presence of feedback. If, as we purport, the edge localised mode (ELM) process is captured by an MLE model with feedback, then a conclusion is that ELMs can be reduced if feedback effects are reduced.
Twisted ion waves carrying orbital angular momentum in a dense pair-ion plasma
Authors: Khan S. A.
Published: January 2018

Electrostatic ion oscillations carrying finite orbital angular momentum are investigated in an unmagnetized dense quantum degenerate plasma containing electrons, positrons, and ions. Instead of conventional plane wave solutions, Laguerre-Gaussian (LG) type density and potential profiles are considered to solve the wave equation in paraxial approximation. The solutions exhibit finite orbital angular momentum states associated with the ion waves. The electric field structure, energy density, and orbital angular momentum density are theoretically examined. In addition, the numerical analysis is carried out to study the effects of positron concentration on the waves for various radial and angular mode numbers and azimuthal angles. The variation of LG potential and azimuthal field amplitudes with positrons is elaborated. The study has relevance with the possible phonon modes and twisted excitation in dense plasmas in the environment of radiation beams associated with optical vortices or stimulated Brillouin scattering.
Graphene levitation and orientation control using a magnetic field
Authors: Niu Chao , Lin Feng , Wang Zhiming M. , Bao Jiming , Hu Jonathan
Published: January 2018

This paper studies graphene levitation and orientation control using a magnetic field. The torques in all three spatial directions induced by diamagnetic forces are used to predict stable conditions for different shapes of millimeter-sized graphite plates. We find that graphite plates, in regular polygon shapes with an even number of sides, will be levitated in a stable manner above four interleaved permanent magnets. In addition, the orientation of micrometer-sized graphene flakes near a permanent magnet is studied in both air and liquid environments. Using these analyses, we are able to simulate optical transmission and reflection on a writing board and thereby reveal potential applications using this technology for display screens. Understanding the control of graphene flake orientation will lead to the discovery of future applications using graphene flakes.
Instrumentation for low noise nanopore-based ionic current recording under laser illumination
Authors: Roelen Zachary , Bustamante José A. , Carlsen Autumn , Baker-Murray Aidan , Tabard-Cossa Vincent
Published: January 2018

We describe a nanopore-based optofluidic instrument capable of performing low-noise ionic current recordings of individual biomolecules under laser illumination. In such systems, simultaneous optical measurements generally introduce significant parasitic noise in the electrical signal, which can severely reduce the instrument sensitivity, critically hindering the monitoring of single-molecule events in the ionic current traces. Here, we present design rules and describe simple adjustments to the experimental setup to mitigate the different noise sources encountered when integrating optical components to an electrical nanopore system. In particular, we address the contributions to the electrical noise spectra from illuminating the nanopore during ionic current recording and mitigate those effects through control of the illumination source and the use of a PDMS layer on the SiNx membrane. We demonstrate the effectiveness of our noise minimization strategies by showing the detection of DNA translocation events during membrane illumination with a signal-to-noise ratio of ∼10 at 10 kHz bandwidth. The instrumental guidelines for noise minimization that we report are applicable to a wide range of nanopore-based optofluidic systems and offer the possibility of enhancing the quality of synchronous optical and electrical signals obtained during single-molecule nanopore-based analysis.
Normal stress effects on Knudsen flow
Authors: Eu Byung Chan
Published: January 2018

Normal stress effects are investigated on tube flow of a single-component non-Newtonian fluid under a constant pressure gradient in a constant temperature field. The generalized hydrodynamic equations are employed, which are consistent with the laws of thermodynamics. In the cylindrical tube flow configuration, the solutions of generalized hydrodynamic equations are exactly solvable and the flow velocity is obtained in a simple one-dimensional integral quadrature. Unlike the case of flow in the absence of normal stresses, the flow develops an anomaly in that the flow in the boundary layer becomes stagnant and the thickness of such a stagnant velocity boundary layer depends on the pressure gradient, the aspect ratio of the radius to the length of the tube, and the pressure (or density and temperature) at the entrance of the tube. The volume flow rate formula through the tube is derived for the flow. It generalizes the Knudsen flow rate formula to the case of a non-Newtonian stress tensor in the presence of normal stress differences. It also reduces to the Navier–Stokes theory formula in the low shear rate limit near equilibrium.
Configuring PSx tetrahedral clusters in Li-excess Li7P3S11 solid electrolyte
Authors: Jung Wo Dum , Yun Bin-Na , Jung Hun-Gi , Choi Sungjun , Son Ji-Won , Lee Jong-Ho , Lee Jong-Heun , Kim Hyoungchul
Published: January 2018

We demonstrate that the Li-ion conductivity can be improved by adding a certain amount of Li (x = 0.25–0.5) as a charge carrier to the composition of glass-ceramic Li7+xP3S11. Structural analysis clarified that the structural changes caused by the ratio of ortho-thiophosphate tetrahedra PS43− and pyro-thiophosphate ditetrahedra P2S74− affect the Li-ion conductivity. The ratio of PS43− and P2S74− varies depending on x and the highest Li-ion conductivity (2.5 × 10−3 S cm−1) at x = 0.25. All-solid-state LiNi0.8Co0.15Al0.05O2/Li7.25P3S11/In-metal cell exhibits the discharge capacity of 106.2 mAh g−1. This ion conduction enhancement from excess Li is expected to contribute to the future design of sulfide-type electrolytes.
Bandgap behavior and singularity of the domain-induced light scattering through the pressure-induced ferroelectric transition in relaxor ferroelectric AxBa1–xNb2O6 (A: Sr,Ca)
Authors: Ruiz-Fuertes J. , Gomis O. , Segura A. , Bettinelli M. , Burianek M. , Mühlberg M.
Published: January 2018

In this letter, we have investigated the electronic structure of AxBa1–xNb2O6 relaxor ferroelectrics on the basis of optical absorption spectroscopy in unpoled single crystals with A = Sr and Ca under high pressure. The direct character of the fundamental transition could be established by fitting Urbach's rule to the photon energy dependence of the absorption edge yielding bandgaps of 3.44(1) eV and 3.57(1) eV for A = Sr and Ca, respectively. The light scattering by ferroelectric domains in the pre-edge spectral range has been studied as a function of composition and pressure. After confirming with x-ray diffraction the occurrence of the previously observed ferroelectric to paraelelectric phase transition at 4 GPa, the light scattering produced by micro- and nano-ferroelectric domains at 3.3 eV in Ca0.28Ba0.72Nb2O6 has been probed. The direct bandgap remains virtually constant under compression with a drop of only 0.01 eV around the phase transition. Interestingly, we have also found that light scattering by the polar nanoregions in the paraelectric phase is comparable to the dispersion due to ferroelectric microdomains in the ferroelectric state. Finally, we have obtained that the bulk modulus of the ferroelectric phase of Ca0.28Ba0.72Nb2O6 is B0 = 222(9) GPa.
Spontaneous perpendicular exchange bias effect in L1-MnGa/FeMn bilayers grown by molecular-beam epitaxy
Authors: Zhao X. P. , Lu J. , Mao S. W. , Yu Z. F. , Wei D. H. , Zhao J. H.
Published: January 2018

We report on the spontaneous perpendicular exchange bias effect in as-grown L10-MnGa/FeMn bilayers. An FeMn layer with different thicknesses is introduced as an antiferromagnetic layer to couple with single-crystalline ferromagnetic L10-MnGa, which is epitaxially grown on a GaAs (001) substrate by molecular-beam epitaxy. The perpendicular exchange bias shows a strong dependence on both the thickness of the FeMn layer and the measurement temperature. A large spontaneous perpendicular exchange bias up to 8.9 kOe is achieved in L10-MnGa/FeMn bilayers at 5 K without any external magnetic treatment. The corresponding effective interfacial exchange energy Jeff is estimated to be 1.4 mJ/m2. The spontaneous perpendicular exchange bias effect in the (001) textured L10-MnGa/FeMn bilayers paves the way for spintronic devices based on exchange biased perpendicularly magnetized materials.
Mid-infrared two-photon absorption in an extended-wavelength InGaAs photodetector
Authors: Piccardo Marco , Rubin Noah A. , Meadowcroft Lauren , Chevalier Paul , Yuan Henry , Kimchi Joseph , Capasso Federico
Published: January 2018

We investigate the nonlinear optical response of a commercial extended-wavelength In0.81Ga0.19As uncooled photodetector. Degenerate two-photon absorption in the mid-infrared range is observed using a quantum cascade laser emitting at λ = 4.5 μm as the excitation source. From the measured two-photon photocurrent signal, we extract a two-photon absorption coefficient β(2) = 0.6 ± 0.2 cm/MW, in agreement with the theoretical value obtained from the Eg−3 scaling law. Considering the wide spectral range covered by extended-wavelength InxGa1–xAs alloys, this result holds promise for applications based on two-photon absorption for this family of materials at wavelengths between 1.8 and 5.6 μm.
Periodic solutions of superlinear Dirac equations with perturbations from symmetry
Authors: Ding Yanheng , Liu Xiaoying
Published: January 2018

Using the variational method, we study superlinear Dirac equations with perturbations from symmetry. We establish the variational setting and obtain infinite many periodic solutions.
Coyote diet patterns in the Mojave Desert: implications for threatened desert tortoises
Authors: Cypher Brian L. , Kelly Erica C. , Westall Tory L. , Van Horn Job Christine L.
Published: January 2018

Coyotes (Canis latrans) are generalist predators and are ubiquitous in North America. Occasionally, predation by coyotes can pose a threat to populations of rare species. We assessed diet patterns of coyotes over a 5-year period (2009–14) in a region of the Mojave Desert where high predation rates on threatened desert tortoises (Gopherus agassizii) had been reported. Our goal was to identify primary food items for coyotes and to assess the importance of desert tortoises in the diet. Coyotes primarily consumed rabbits and rodents with rabbits being consumed preferentially and rodents, along with secondary foods including various birds, reptiles, arthropods, and fruits, being consumed more opportunistically. In response to low annual precipitation in the last three years of the study, dietary diversity increased, as did use of anthropogenic food items by coyotes. However, coyotes did not seem to be dependent upon anthropogenic items. Remains of desert tortoises occurred in coyote scats at low frequencies (<6%) in all years and seasons, and use of tortoises appeared to be opportunistic as use varied with tortoise abundance. In the portion of the study area where 571 translocated desert tortoises had been released in 2008, the frequencies of tortoise remains in coyote scats were markedly higher in the two years following the releases (7.5% and 8.8%, respectively). The high predation rates on tortoises reported in this area may have resulted from focussed coyote foraging efforts due to the availability of vulnerable individuals (e.g. disoriented and displaced tortoises) as well as higher tortoise densities.