bluuebunny/crossref_metadata_2025 huggingface dataset:
Resonant driving of a single photon emitter embedded in a mechanical oscillator
Authors: Munsch Mathieu , Kuhlmann Andreas V. , Cadeddu Davide , Gérard Jean-Michel , Claudon Julien , Poggio Martino , Warburton Richard J.
Published: July 2017

Coupling a microscopic mechanical resonator to a nanoscale quantum system enables control of the mechanical resonator via the quantum system and vice-versa. The coupling is usually achieved through functionalization of the mechanical resonator, but this results in additional mass and dissipation channels. An alternative is an intrinsic coupling based on strain. Here we employ a monolithic semiconductor system: the nanoscale quantum system is a semiconductor quantum dot (QD) located inside a nanowire. We demonstrate the resonant optical driving of the QD transition in such a structure. The noise spectrum of the resonance fluorescence signal, recorded in the single-photon counting regime, reveals a coupling to mechanical modes of different types. We measure a sensitivity to displacement of 65 fm/$$\sqrt {{\rm{Hz}}} $$

Hz

limited by charge noise in the device. Finally, we use thermal excitation of the different modes to determine the location of the QD within the trumpet, and calculate the contribution of the Brownian motion to the dephasing of the emitter.
Draft whole genome sequence of groundnut stem rot fungus Athelia rolfsii revealing genetic architect of its pathogenicity and virulence
Authors: Iquebal M. A. , Tomar Rukam S. , Parakhia M. V. , Singla Deepak , Jaiswal Sarika , Rathod V. M. , Padhiyar S. M. , Kumar Neeraj , Rai Anil , Kumar Dinesh
Published: July 2017

Groundnut (Arachis hypogaea L.) is an important oil seed crop having major biotic constraint in production due to stem rot disease caused by fungus, Athelia rolfsii causing 25–80% loss in productivity. As chemical and biological combating strategies of this fungus are not very effective, thus genome sequencing can reveal virulence and pathogenicity related genes for better understanding of the host-parasite interaction. We report draft assembly of Athelia rolfsii genome of ~73 Mb having 8919 contigs. Annotation analysis revealed 16830 genes which are involved in fungicide resistance, virulence and pathogenicity along with putative effector and lethal genes. Secretome analysis revealed CAZY genes representing 1085 enzymatic genes, glycoside hydrolases, carbohydrate esterases, carbohydrate-binding modules, auxillary activities, glycosyl transferases and polysaccharide lyases. Repeat analysis revealed 11171 SSRs, LTR, GYPSY and COPIA elements. Comparative analysis with other existing ascomycotina genome predicted conserved domain family of WD40, CYP450, Pkinase and ABC transporter revealing insight of evolution of pathogenicity and virulence. This study would help in understanding pathogenicity and virulence at molecular level and development of new combating strategies. Such approach is imperative in endeavour of genome based solution in stem rot disease management leading to better productivity of groundnut crop in tropical region of world.
Small cell lung cancer: model of circulating tumor cell tumorospheres in chemoresistance
Authors: Klameth Lukas , Rath Barbara , Hochmaier Maximilian , Moser Doris , Redl Marlene , Mungenast Felicitas , Gelles Katharina , Ulsperger Ernst , Zeillinger Robert , Hamilton Gerhard
Published: July 2017

Small cell lung cancer (SCLC) represents 15% of lung cancers and is characterized by early dissemination, development of chemoresistance and a poor prognosis. A host of diverse drugs failed invariably and its mechanisms of global chemoresistance have not been characterized so far. SCLC represents the prototype of an aggressive and highly metastatic tumor which is ultimately refractory to any treatment. High numbers of circulating tumor cells (CTCs) allowed us to establish 5 CTC cell lines (BHGc7, 10, 16, 26 and UHGc5) from patients with recurrent SCLC. These cell lines exhibit the typical SCLC markers and CTCs of all patients developed spontaneously large multicellular aggregates, termed tumorospheres. Ki67 and carbonic anhydrase 9 (CAIX) staining of tumorosphere sections revealed quiescent and hypoxic cells, respectively. Accordingly, comparison of the chemosensitivity of CTC single cell suspensions with tumorospheres demonstrated increased resistance of the clusters against chemotherapeutics commonly used for treatment of SCLC. Therefore, global chemoresistance of relapsing SCLC seems to rely on formation of large tumorospheres which reveal limited accessibility, lower growth fraction and hypoxic conditions. Since similar tumor spheroids were found in other tumor types, SCLC seems to represent a unique tumor model to study the association of CTCs, metastasis and drug resistance.
Defective Sphingosine-1-phosphate metabolism is a druggable target in Huntington’s disease
Authors: Di Pardo Alba , Amico Enrico , Basit Abdul , Armirotti Andrea , Joshi Piyush , Neely M. Diana , Vuono Romina , Castaldo Salvatore , Digilio Anna F. , Scalabrì Francesco , Pepe Giuseppe , Elifani Francesca , Madonna Michele , Jeong Se Kyoo , Park Bu-Mahn , D’Esposito Maurizio , Bowman Aaron B. , Barker Roger A. , Maglione Vittorio
Published: July 2017

Huntington’s disease is characterized by a complex and heterogeneous pathogenic profile. Studies have shown that disturbance in lipid homeostasis may represent a critical determinant in the progression of several neurodegenerative disorders. The recognition of perturbed lipid metabolism is only recently becoming evident in HD. In order to provide more insight into the nature of such a perturbation and into the effect its modulation may have in HD pathology, we investigated the metabolism of Sphingosine-1-phosphate (S1P), one of the most important bioactive lipids, in both animal models and patient samples. Here, we demonstrated that S1P metabolism is significantly disrupted in HD even at early stage of the disease and importantly, we revealed that such a dysfunction represents a common denominator among multiple disease models ranging from cells to humans through mouse models. Interestingly, the in vitro anti-apoptotic and the pro-survival actions seen after modulation of S1P-metabolizing enzymes allows this axis to emerge as a new druggable target and unfolds its promising therapeutic potential for the development of more effective and targeted interventions against this incurable condition.
Association of wall shear stress with intracranial aneurysm rupture: systematic review and meta-analysis
Authors: Zhou Geng , Zhu Yueqi , Yin Yanling , Su Ming , Li Minghua
Published: July 2017

To evaluate the relationship between wall shear stress (WSS) magnitude and cerebral aneurysm rupture and provide new insight into the disparate computational fluid dynamics (CFD) findings concerning the role of WSS in intracranial aneurysm (IA) rupture. A systematic electronic database (PubMed, Medline, Springer, and EBSCO) search was conducted for all accessible published articles up to July 1, 2016, with no restriction on the publication year. Abstracts, full-text manuscripts, and the reference lists of retrieved articles were analyzed. Random effects meta-analysis was used to pool the complication rates across studies. Twenty-two studies containing CFD data on 1257 patients with aneurysms were included in the analysis. A significantly higher rate of low WSS (0–1.5 Pa) was found in ruptured aneurysms (odds ratio [OR] 2.17; 95% confidence interval [CI], 1.73–2.62). The pooled analyses across 14 studies with low WSS showed significantly lower mean WSS (0.64 vs. 1.4 Pa) (p = 0.037) in the ruptured group. This meta-analysis provides evidence that decreased local WSS may be an important predictive parameter of IA rupture.
Naphthalene amine support for G-quadruplex isolation
Authors: Ferreira João , Santos Tiago , Pereira Patrícia , Corvo Marta C. , Queiroz João A. , Sousa Fani , Cruz Carla
Published: July 2017

The selective isolation of G-quadruplex (G4) using affinity ligands that bind tightly and selectively is a valuable strategy for discovering new G4 binders for the separation of G4 from duplexes or the discrimination of G4 structures.
Direct monitoring of lipid transfer on exposure of citrem nanoparticles to an ethanol solution containing soybean phospholipids by combining synchrotron SAXS with microfluidics
Authors: Khaliqi K. , Ghazal A. , Azmi I. D. M. , Amenitsch H. , Mortensen K. , Salentinig S. , Yaghmur A.
Published: July 2017

Lipid exchange among citrem nanoparticles and an ethanol micellar solution containing soy phosphatidylcholine was investigated in situ by coupling small angle X-ray scattering with a microfluidic device.
Understanding the metabolism of the anticancer drug Triapine: electrochemical oxidation, microsomal incubation and in vivo analysis using LC-HRMS
Authors: Pelivan Karla , Frensemeier Lisa , Karst Uwe , Koellensperger Gunda , Bielec Bjoern , Hager Sonja , Heffeter Petra , Keppler Bernhard K. , Kowol Christian R.
Published: July 2017

The metabolism of the anticancer thiosemicarbazone Triapine was investigated.
A surface plasmon field-enhanced fluorescence reversible split aptamer biosensor
Authors: Sergelen K. , Liedberg B. , Knoll W. , Dostálek J.
Published: July 2017

Surface plasmon-enhanced fluorescence for the readout of a assay with low affinity split aptamer.
Tripartite polyionic complex (PIC) micelles as non-viral vectors for mesenchymal stem cell siRNA transfection
Authors: Raisin Sophie , Morille Marie , Bony Claire , Noël Danièle , Devoisselle Jean-Marie , Belamie Emmanuel
Published: July 2017

In this study, we demonstrate that PIC micelles readily form at physiological pH in the presence of siRNA and disassemble at a pH close to that of endosomes. Internalization of the micelles in primary MSC results in the down-regulation of Runx2.
Palladium-catalyzed dearomatizative [2 + 2 + 1] carboannulation of 1,7-enynes with aryl diazonium salts and H2O: facile synthesis of spirocyclohexadienone-fused cyclopenta[c]quinolin-4(5H)-ones
Authors: Liu Yu , Song Ren-Jie , Li Jin-Heng
Published: July 2017

The first 1,7-enyne dearomatizative [2 + 2 + 1] carboannulation using aryl diazonium salts as the one-carbon units is described.
Visible-light-induced thiotrifluoromethylation of terminal alkenes with sodium triflinate and benzenesulfonothioates
Authors: Kong Weiguang , An Hejun , Song Qiuling
Published: July 2017

An unconventional reductive quenching cycle was developed to realize the visible-light-induced thiotrifluoromethylation of terminal alkenes.
Synthesis of seminaphtho-phospha-fluorescein dyes based on the consecutive arylation of aryldichlorophosphines
Authors: Fukazawa Aiko , Usuba Junichi , Adler Raúl A. , Yamaguchi Shigehiro
Published: July 2017

Seminaphtho-phospha-fluorescein, a phosphine oxide-containing unsymmetric fluorescein dye with NIR fluorescence, was synthesized based on the consecutive arylation of PhPCl2.
Strong ferromagnetic exchange coupling in a {NiII4} cluster mediated through an air-stable tetrazine-based radical anion
Authors: Lemes Maykon A. , Brunet Gabriel , Pialat Amélie , Ungur Liviu , Korobkov Ilia , Murugesu Muralee
Published: July 2017

A planar tetradentate 3,6-bis(2-pyrimidyl)-1,2,4,5-tetrazine (BpymTz) templating chelate affords the formation of an unprecedented BpymTz˙−radical anion bridged {NiII4} complex with strong ferromagnetic interaction.
sp2CH⋯Cl hydrogen bond in the conformational polymorphism of 4-chloro-phenylanthranilic acid
Authors: Liu Meng , Yin Chuming , Chen Peng , Zhang Mingtao , Parkin Sean , Zhou Panpan , Li Tonglei , Yu Faquan , Long Sihui
Published: July 2017

Conformational flexibility andsp2CH⋯Cl hydrogen bond lead to three polymorphs of 4-chloro-phenylanthranilic acid.
Non-invasively improving the Schottky barriers of metal–MoS2interfaces: effects of atomic vacancies in a BN buffer layer
Authors: Su Jie , Feng Liping , Liu Siyang , Liu Zhengtang
Published: July 2017

Using first-principles calculations within density functional theory, vacancies in the BN buffer layer have been predicted to improve the Schottky barrier of the metal–MoS2interface without deteriorating the intrinsic properties of the MoS2layer.
DNA–surfactant complexes: self-assembly properties and applications
Authors: Liu Kai , Zheng Lifei , Ma Chao , Göstl Robert , Herrmann Andreas
Published: July 2017

This review provides a comprehensive overview of the preparation, self-assembly properties, and various applications from optoelectronics to biomedicine of DNA–surfactant complexes.
Cross-coupling of aromatic esters and amides
Authors: Takise Ryosuke , Muto Kei , Yamaguchi Junichiro
Published: July 2017

This review highlights the progress in transition-metal-catalyzed decarbonylative and non-decarbonylative cross-coupling of aromatic esters and aromatic amides.
A gigantic polyoxozirconate with visible photoactivity
Authors: Xu Tingting , Hou Xudong , Wang Yang , Zhang Jun , Zhang Junxiang , Liu Bo
Published: July 2017

We present the synthesis and structure of a gigantic polyoxozirconate nanocluster (Zr18O21(μ2-OH)2(OOCPh)28), involving 6, 7 and 8-coordinated Zr atoms. It represents the largest and the first visible-active polyoxozirconate so far. And the cluster exhibits visible light driven photocatalytic activity for H2 production.
Ru(ii)-(PTA) and -mPTA complexes with N2-donor ligands bipyridyl and phenanthroline and their antiproliferative activities on human multiple myeloma cell lines
Authors: Wołoszyn Aleksandra , Pettinari Claudio , Pettinari Riccardo , Badillo Patzmay Gretta Veronica , Kwiecień Anna , Lupidi Giulio , Nabissi Massimo , Santoni Giorgio , Smoleński Piotr
Published: July 2017

Antiproliferative activities on human multiple myeloma cell lines of a series of novel ruthenium(ii) bpy and phen derivatives containing PTA and mPTA ligands.
Manganese-mediated synthesis of an NHC core non-symmetric pincer ligand and evaluation of its coordination properties
Authors: Valyaev Dmitry A. , Willot Jérémy , Mangin Loïc P. , Zargarian Davit , Lugan Noël
Published: July 2017

Alkylation of N-(2-pyridyl)imidazole with [Cp(CO)2Mn(η2-P,C-Ph2PC(H)Ph)]BF4 followed by in situ photochemical demetallation leads to an NHC-core non-symmetric PĈN pro-ligand, whose aptitude to coordinate in a pincer mode was recognized in RhI, RhIII and NiII complexes.
One-pot and catalyst-free synthesis of pyrroloquinolinediones and quinolinedicarboxylates
Authors: Zhang Xiaofeng , Dhawan Gagan , Muthengi Alex , Liu Shuai , Wang Wei , Legris Marc , Zhang Wei
Published: July 2017

A method for the catalyst-free synthesis of pyrroloquinolinediones and quinolinedicarboxylates is developed through a one-pot synthesis involving denitrogenation of azide, benzisoxazole formation, aza-Diels–Alder cycloaddition, and dehydrative aromatization.
Application of microwave-assisted heterogeneous catalysis in sustainable synthesis design
Authors: Kokel Anne , Schäfer Christian , Török Béla
Published: July 2017

Recent advances in the application of microwave-assisted heterogeneous catalytic synthesis approaches are reviewed with additional inputs on the energy efficiency and scale-up of microwave-assisted synthesis.
Gelation behaviour and gel properties of two-component organogels containing a photoresponsive gelator
Authors: Che Xiangyang , Bai Binglian , Zhang Tianren , Zhang Chunling , Zhang Chunxue , Zhang Peng , Wang Haitao , Li Min
Published: July 2017

Herein, we report the gelation behaviour and gel properties of two-component organogels consisting of 1,4-bis[(3,4-bisoctyloxyphenyl) hydrozide] phenylene (BPH-8) and a photoresponsive gelator 4-[3,5-(bisoctyloxyphenyl)]-9-anthracene formyl hydrazine (MB8).
Highly selective oxidation of methanol to dimethoxymethane over SO42−/V2O5–ZrO2
Authors: Tao Meng , Wang Hongxia , Bin Lu Bin Lu , Zhao Jingxiang , Cai Qinghai
Published: July 2017

SO42−/V2O5–ZrO2was an effective catalyst for the oxidation of methanol to dimethoxymethane, being mainly ascribed to the V2O5crystalline species.
Investigating the magnitude and source of orientation-dependent interactions between TiO2 crystal surfaces
Authors: Li Dongsheng , Wang Hailong , Xiao Dongdong , Song Miao , Legg Benjamin , Chun Jaehun
Published: July 2017

Forces between rutile (001) planes in water were measured by using oriented single crystal AFM tips, exhibiting 90° periodicity induced by vdW interactions and mainly H-bonding.
Increasing the solubility range of polyesters by tuning their microstructure with comonomers
Authors: Delgove Marie A. F. , Luchies Juandré , Wauters Iris , Deroover Geert G. P. , De Wildeman Stefaan M. A. , Bernaerts Katrien V.
Published: July 2017

Improved solubility of ω-pentadecalactone based copolymers was induced by copolymerization with branched lactones to increase randomness as shown by13C-NMR/MALDI-ToF MS.
Accurate analysis of the size distribution and crystallinity of boron doped Si nanocrystals via Raman and PL spectra
Authors: Jia X. , Lin Z. , Zhang T. , Puthen-Veettil B. , Yang T. , Nomoto K. , Ding J. , Conibeer G. , Perez-Wurfl I.
Published: July 2017

Through fitting of Raman and PL spectra, Si nanocrystal size distributions and Si crystalline fractions are obtained.
Amphiphilic silane modified multifunctional nanoparticles for ratiometric oxygen sensing
Authors: Lin Yanxia , Xu Hongwei , Dong Biao , Sun Xueke , Li Chunhe , Li Jianing , Xu Lin , Bai Xue , Song Hongwei
Published: July 2017

Precise detection of dissolved oxygen (DO) at the cellular level plays a pivotal role in the diagnosis of many diseases and intraoperative observation.
Thermodynamics of chemical Marangoni-driven engines
Authors: Krechetnikov Rouslan
Published: July 2017

A general thermodynamic study of Marangoni-driven engines in which chemical energy is directly transformed into mechanical motion.
A Qualitative Study Describing Positive and Negative Supervisor-Student Clinician Relationships in Speech-Language Pathology
Authors: Fencel Jessica Atick , Mead Jean Suzanne
Published: July 2017

The purpose of this study was to gain an understanding of the factors that constitute positive and negative supervisor/supervisee relationships as perceived by speech-language pathology graduate interns. Experiences were analyzed using qualitative methods via participant interviews. Two overlaying themes, ASHA's Task 1 of Supervision and Anderson's Continuum Model of Supervision, were identified and used as a framework for categorizing the participant responses. Analysis of the data indicated that the factors most likely to result in a positive clinical experience included constructive feedback, respect, positive praise, clear expectations, and structured clinical guidance while factors that most likely attributed to a negative experience were lack of the above-mentioned.
Parameter estimation of the fractional‐order Hammerstein–Wiener model using simplified refined instrumental variable fractional‐order continuous time
Authors: Allafi Walid , Zajic Ivan , Uddin Kotub , Burnham Keith J.
Published: July 2017

This study proposes a direct parameter estimation approach from observed input–output data of a stochastic single‐input–single‐output fractional‐order continuous‐time Hammerstein–Wiener model by extending a well known iterative simplified refined instrumental variable method. The method is an extension of the simplified refined instrumental variable method developed for the linear fractional‐order continuous‐time system, denoted. The advantage of this novel extension, compared with published methods, is that the static output non‐linearity of the Wiener model part does not need to be invertible. The input and output static non‐linear functions are represented by a sum of the known basis functions. The proposed approach estimates the parameters of the linear fractional‐order continuous‐time subsystem and the input and output static non‐linear functions from the sampled input–output data by considering the system to be a multi‐input–single‐output linear fractional‐order continuous‐time model. These extra inputs represent the basis functions of the static input and output non‐linearity, where the output basis functions are simulated according to the previous estimates of the fractional‐order linear subsystem and the static input non‐linear function at every iteration. It is also possible to estimate the classical integer‐order model counterparts as a special case. Subsequently, the proposed extension to the simplified refined instrumental variable method is considered in the classical integer‐order continuous‐time Hammerstein–Wiener case. In this paper, a Monte Carlo simulation analysis is applied for demonstrating the performance of the proposed approach to estimate the parameters of a fractional‐order Hammerstein–Wiener output model.
Characterizing the astrometric precision limit for moving targets observed with digital-array detectors
Authors: Bouquillon S. , Mendez R. A. , Altmann M. , Carlucci T. , Barache C. , Taris F. , Andrei A. H. , Smart R.
Published: July 2017

Aims. We investigate the maximum astrometric precision that can be reached on moving targets observed with digital-sensor arrays, and provide an estimate for its ultimate lower limit based on the Cramér-Rao bound.

Methods. We extend previous work on one-dimensional Gaussian point-spread functions (PSFs) focusing on moving objects and extending the scope to two-dimensional array detectors. In this study the PSF of a stationary point-source celestial body is replaced by its convolution with a linear motion, thus effectively modeling the spread function of a moving target.

Results. The expressions of the Cramér-Rao lower bound deduced by this method allow us to study in great detail the limit of astrometric precision that can be reached for moving celestial objects, and to compute an optimal exposure time according to different observational parameters such as seeing, detector pixel size, decentering, and elongation of the source caused by its drift. Comparison to simulated and real data shows that the predictions of our simple model are consistent with observations.
Impact of a cometary outburst on its ionosphere
Authors: Hajra R. , Henri P. , Vallières X. , Galand M. , Héritier K. , Eriksson A. I. , Odelstad E. , Edberg N. J. T. , Burch J. L. , Broiles T. , Goldstein R. , Glassmeier K. H. , Richter I. , Goetz C. , Tsurutani B. T. , Nilsson H. , Altwegg K. , Rubin M.
Published: July 2017

We present a detailed study of the cometary ionospheric response to a cometary brightness outburst using in situ measurements for the first time. The comet 67P/Churyumov-Gerasimenko (67P) at a heliocentric distance of 2.4 AU from the Sun, exhibited an outburst at ~1000 UT on 19 February 2016, characterized by an increase in the coma surface brightness of two orders of magnitude. The Rosetta spacecraft monitored the plasma environment of 67P from a distance of 30 km, orbiting with a relative speed of ~0.2 m s-1. The onset of the outburst was preceded by pre-outburst decreases in neutral gas density at Rosetta, in local plasma density, and in negative spacecraft potential at ~0950 UT. In response to the outburst, the neutral density increased by a factor of ~1.8 and the local plasma density increased by a factor of ~3, driving the spacecraft potential more negative. The energetic electrons (tens of eV) exhibited decreases in the flux of factors of ~2 to 9, depending on the energy of the electrons. The local magnetic field exhibited a slight increase in amplitude (~5 nT) and an abrupt rotation (~36.4°) in response to the outburst. A weakening of 10–100 mHz magnetic field fluctuations was also noted during the outburst, suggesting alteration of the origin of the wave activity by the outburst. The plasma and magnetic field effects lasted for about 4 h, from ~1000 UT to 1400 UT. The plasma densities are compared with an ionospheric model. This shows that while photoionization is the main source of electrons, electron-impact ionization and a reduction in the ion outflow velocity need to be accounted for in order to explain the plasma density enhancement near the outburst peak.
Constructing an autonomous system with infinitely many chaotic attractors
Authors: Zhang Xu , Chen Guanrong
Published: July 2017

Some classical chaotic systems such as the Lorenz system and Chua system have finite numbers of chaotic attractors. This letter develops a simple, effective method for constructing lower-dimensional autonomous systems with infinitely many chaotic attractors. As an application, a Lorenz-type system and a Rössler-type system with infinitely many chaotic attractors are constructed with bifurcation analysis, and with an extension to the fractional-order setting.
Two prospective Li-based half-Heusler alloys for spintronic applications based on structural stability and spin–orbit effect
Authors: Zhang R. L. , Damewood L. , Zeng Y. J. , Xing H. Z. , Fong C. Y. , Yang L. H. , Peng R. W. , Felser C.
Published: July 2017

To search for half-metallic materials for spintronic applications, instead of using an expensive trial-and-error experimental scheme, it is more efficient to use first-principles calculations to design materials first, and then grow them. In particular, using a priori information of the structural stability and the effect of the spin–orbit interaction (SOI) enables experimentalists to focus on favorable properties that make growing half-metals easier. We suggest that using acoustic phonon spectra is the best way to address the stability of promising half-metallic materials. Additionally, by carrying out accurate first-principles calculations, we propose two criteria for neglecting the SOI so the half-metallicity persists. Based on the mechanical stability and the negligible SOI, we identified two half-metals, β-LiCrAs and β-LiMnSi, as promising half-Heusler alloys worth growing.
Physics-based parametrization of the surface impedance for radio frequency sheaths
Authors: Myra J. R.
Published: July 2017

The properties of sheaths near conducting surfaces are studied for the case where both magnetized plasma and intense radio frequency (rf) waves coexist. The work is motivated primarily by the need to understand, predict, and control ion cyclotron range of frequency (ICRF) interactions with tokamak scrape-off layer plasmas and is expected to be useful in modeling rf sheath interactions in global ICRF codes. Employing a previously developed model for oblique angle magnetized rf sheaths [J. R. Myra and D. A. D'Ippolito, Phys. Plasmas 22, 062507 (2015)], an investigation of the four-dimensional parameter space governing these sheath is carried out. By combining numerical and analytical results, a parametrization of the surface impedance and voltage rectification for rf sheaths in the entire four-dimensional space is obtained.
Coupled-cluster based approach for core-level states in condensed phase: Theory and application to different protonated forms of aqueous glycine
Authors: Sadybekov Arman , Krylov Anna I.
Published: July 2017

A theoretical approach for calculating core-level states in condensed phase is presented. The approach is based on the equation-of-motion coupled-cluster (EOM-CC) theory and effective fragment potential (EFP) method. By introducing approximate treatment of double excitations in the EOM-CC with single and double substitutions ansatz, we address poor convergence issues that are encountered for the core-level states and significantly reduce computational costs. While the approximations introduce relatively large errors in the absolute values of transition energies, the errors are systematic. Consequently, chemical shifts, changes in ionization energies relative to reference systems, are reproduced reasonably well. By using different protonation forms of solvated glycine as a benchmark system, we show that our protocol is capable of reproducing the experimental chemical shifts with a quantitative accuracy. The results demonstrate that chemical shifts are very sensitive to the solvent interactions and that explicit treatment of a solvent, such as within EFP framework, is essential for achieving quantitative accuracy.
On detachment asymmetry and stability
Authors: Pshenov A. A. , Kukushkin A. S. , Krasheninnikov S. I.
Published: July 2017

Three issues related to the physics of divertor detachment are analyzed in detail: the criteria for the onset of complete divertor detachment, the role of neutrals in “symmetryzation” of detachment in the inner and outer divertors, and the transition to divertor detachment. The results of comprehensive 2D numerical simulations with the SOLPS4.3 package are compared with some experimental data and predictions based on simplified analytical models. It is shown that it is the ratio of the upstream plasma pressure to the specific power flux entering the recycling region that controls the local onset of detachment on a specific flux tube. Pup/qreclycl≥(Pup/qreclycl)crit remains the valid criterion also in the presence of seeded impurity, if the impurity radiation and hydrogen recycling regions are spatially separated. Detailed analysis indicates that the reverse plasma flow forming on the most heat loaded flux tubes in the outer divertor under the influence of the neutrals coming from the deeply detached inner divertor plays the key role in the detachment “symmetryzation” and allows the outer divertor to reach the detached regime. Finally, it is demonstrated that a gradual increase of the perpendicular heat transport in the edge plasma during transition to the detached regime can make this transition bifurcation-like.
Enhancement of keV X-rays from low-density cellulose triacetate (TAC) foam targets
Authors: Chaurasia S. , Kaur Channprit , Borisenko N. G. , Pasley J. , Orekhov A. , Deo M. N.
Published: July 2017

The interaction of a high-power laser with a low-density foam target can in some instances result in a significant enhancement in x-ray generation relative to that when the same laser is incident upon a homogenous solid. In this paper, we present x-ray emission studies from foam targets where the density is varied from under-dense to over-dense. The targets are irradiated with the first harmonic of Nd:Glass laser. The laser intensity on the target was approximately 2 × 1014 W/cm2 with the pulse duration of 500 ps. Mass-matched cellulose triacetate foam targets with densities of 2 mg/cc, 4 mg/cc, 7 mg/cc, and 20 mg/cc were used. The areal density presented by the targets on the laser beam axis was held constant at 0.2 mg/cm2 by varying the target thickness in inverse proportion to the density. The x-ray yield in the spectral range (5–8 keV) and (4.5–16 keV) was found to be enhanced by approximately 2.3 times in foam targets with the density of 2 mg/cc (under-dense) compared with foam targets with the density of 20 mg/cc (over-dense).
Hot electron generation under large-signal radio frequency operation of GaN high-electron-mobility transistors
Authors: Latorre-Rey Alvaro D. , Sabatti Flavio F. M. , Albrecht John D. , Saraniti Marco
Published: July 2017

In order to assess the underlying physical mechanisms of hot carrier-related degradation such as defect generation in millimeter-wave GaN power amplifiers, we have simulated the electron energy distribution function under large-signal radio frequency conditions in AlGaN/GaN high-electron-mobility transistors. Our results are obtained through a full band Monte Carlo particle-based simulator self-consistently coupled to a harmonic balance circuit solver. At lower frequency, simulations of a Class AB power amplifier at 10 GHz show that the peak hot electron generation is up to 43% lower under RF drive than it is under DC conditions, regardless of the input power or temperature of operation. However, at millimeter-wave operation up to 40 GHz, RF hot carrier generation reaches that from DC biasing and even exceeds it up to 75% as the amplifier is driven into compression. Increasing the temperature of operation also shows that degradation of DC and RF characteristics are tightly correlated and mainly caused by increased phonon scattering. The accurate determination of the electron energy mapping is demonstrated to be a powerful tool for the extraction of compact models used in lifetime and reliability analysis.
Note: Temperature effects in the modified Howland current source for electrical bioimpedance spectroscopy
Authors: Fernandez Santos S. , Bertemes-Filho P.
Published: July 2017

The aim of this study is to show how the modified Howland current source (MHCS) is affected by temperature changes. The source has been tested in a temperature range from 20 to 70 °C and frequency range from 100 Hz to 1 MHz. Parameters like output current, output impedance, total harmonic distortion, and oscillation have been measured. The measurements were made inside a temperature controlled environment. It was showed that the MHCS is stable at temperatures below 70 °C. Operational amplifiers with a low temperature drift and matching resistor should be carefully considered in order to prevent oscillations at high temperatures.
A high output voltage flexible piezoelectric nanogenerator using porous lead-free KNbO3 nanofibers
Authors: Ganeshkumar Rajasekaran , Cheah Chin Wei , Xu Ruize , Kim Sang-Gook , Zhao Rong
Published: July 2017

Self-powered nanodevices for applications such as sensor networks and IoTs are among the emerging technologies in electronics. Piezoelectric nanogenerators (P-NGs) that harvest energy from mechanical stimuli are highly valuable in the development of self-sufficient nanosystems. Despite progress in the development of P-NGs, the use of porous perovskite ferroelectric nanofibers was barely considered or discussed. In this letter, a flexible high output nanogenerator is fabricated using a nanocomposite comprising porous potassium niobate (KNbO3) nanofibers and polydimethylsiloxane. When a compressive force was applied to as-fabricated P-NG, a peak-to-peak output voltage of ∼16 V and a maximum closed circuit current of 230 nA were obtained, which are high enough to realize self-powered nanodevices. In addition, due to their porosity and non-toxic nature, KNbO3 nanofibers may be used as an alternative to the dominant lead-based piezoelectric devices. Besides the high output performance of the device, multifunctional capability, flexible design, and cost-effective construction of the as-fabricated P-NG can be crucial to large-scale deployment of autonomous devices.
BRAFV600inhibition alters the microRNA cargo in the vesicular secretome of malignant melanoma cells
Authors: Lunavat Taral R. , Cheng Lesley , Einarsdottir Berglind O. , Olofsson Bagge Roger , Veppil Muralidharan Somsundar , Sharples Robyn A. , Lässer Cecilia , Gho Yong Song , Hill Andrew F. , Nilsson Jonas A. , Lötvall Jan
Published: July 2017

Significance

The development of BRAF inhibitors is a notable clinical success, leading to rapid initial melanoma regression. However, response rates are tempered by a short duration of response in a majority of patients. This study has determined the effects of BRAF inhibition on mutant melanoma cells, as well as on the RNA contents in their vesicular secretome. Our data show the presence of miR-211–5p in all extracellular vesicular (EV) subsets upon treatment with BRAF inhibitors, which provides a fundamental starting point to understand the regulatory effects of molecules present in EVs, which may have implications for disease progression in patients receiving BRAF-targeted treatment.
Tracing Dietary Mercury Histochemically, with Autometallography, through the Liver to the Ovaries and Spawned Eggs of the Spot, a Temperate Coastal Marine Fish
Authors: Govoni John J. , Morris James A. , Evans David W.
Published: July 2017

Exposure to mercury (Hg) results in reproductive abnormalities and deficiencies in female fish. We traced the maternal assimilation and redistribution of dietary inorganic (HgII) and organic (MeHg) forms of Hg in a coastal marine fish, the Spot Leiostomus xanthurus. We conducted a 90-d laboratory experiment in which treatment Spot were fed muscle of Blue Marlin Makaira nigricans with elevated concentrations of Hg mixed with a commercial fish food, while control Spot were fed only commercial food pellets. Gonadal maturation was induced by shortening the photoperiod and increasing the temperature. Spawning was induced by intramuscular injection of human chorionic gonadotropin at 100 IU/kg. Solid-sampling atomic absorption spectrophotometry measured the total Hg (THg), HgII, and MeHg in Blue Marlin muscle. Autometallography located Hg-sulfide granules in the liver, ovaries, and spawned eggs, and densitometry provided comparisons of Hg-sulfide granules in the ovaries of treatment and control Spot. Overall, the intensity and prevalence of Hg-sulfide granules were greater in the liver, ovaries, and eggs from treatment Spot than in those from controls. The tissue and cellular distribution of Hg-sulfide granules differed.

Received November 18, 2016; accepted June 18, 2017 Published online August 11, 2017
The first artificial hearing aid. Re-evaluating the role of Paolo Aproino
Authors: Mylonakis Ioannis , Martini Alessandro
Published: July 2017

Deafness, with its personal and social burden, has certainly accompanied mankind since the beginning of its existence, meaning that various natural aids to hearing, the cupped human hand the first among them, have assuredly been in use since antiquity. Ear trumpets were essentially the first totally artificial type of hearing aid. The actual history of ear trumpets seems to have begun in the seventeenth century, when written evidence on the matter first appears. The French Jesuit Jean Leurechon, in his Recreation Mathematique of 1624, first mentions funnel-like objects as sound amplifiers, while Sir Francis Bacon, in his Sylva Sylvarum, published in 1627, clearly states that similar objects were already in use as aids to hearing. Giovanni Battista della Porta, in his oft-cited Magiae Naturalis of 1589, offers only a vague and inconclusive description of an aid that would once again imitate natural shell forms and can only be considered as one of the first published references to sound amplification. This work focuses on the contribution of Galileo’s disciple Paolo Aproino who, around 1612–13, presented to Galileo, and through this latter to the court of the Grand duke of Tuscany, an auditory instrument that amplified sound, together with his pioneering experimental studies in the field. Using the experimental method taught by Galileo, Aproino was able to test various forms and materials, deciding upon the final design of the instrument that he then supplied to Galileo in order to construct a metal prototype. This trumpet-like linear ear horn seemed to obtain good results in sound amplification, even though it entailed a certain amount of sound distortion that somewhat reduced the intelligibility of speech. Although Aproino never produced any publications on the matter, his findings became known and impressed the scientific and literary milieu of his time and could therefore have been the initial spur for the future development of sound amplification in the following years.
A module for Rac temporal signal integration revealed with optogenetics
Authors: Graziano Brian R. , Gong Delquin , Anderson Karen E. , Pipathsouk Anne , Goldberg Anna R. , Weiner Orion D.
Published: July 2017

Sensory systems use adaptation to measure changes in signaling inputs rather than absolute levels of signaling inputs. Adaptation enables eukaryotic cells to directionally migrate over a large dynamic range of chemoattractant. Because of complex feedback interactions and redundancy, it has been difficult to define the portion or portions of eukaryotic chemotactic signaling networks that generate adaptation and identify the regulators of this process. In this study, we use a combination of optogenetic intracellular inputs, CRISPR-based knockouts, and pharmacological perturbations to probe the basis of neutrophil adaptation. We find that persistent, optogenetically driven phosphatidylinositol (3,4,5)-trisphosphate (PIP3) production results in only transient activation of Rac, a hallmark feature of adaptive circuits. We further identify the guanine nucleotide exchange factor P-Rex1 as the primary PIP3-stimulated Rac activator, whereas actin polymerization and the GTPase-activating protein ArhGAP15 are essential for proper Rac turnoff. This circuit is masked by feedback and redundancy when chemoattractant is used as the input, highlighting the value of probing signaling networks at intermediate nodes to deconvolve complex signaling cascades.
Membrane tension controls adhesion positioning at the leading edge of cells
Authors: Pontes Bruno , Monzo Pascale , Gole Laurent , Le Roux Anabel-Lise , Kosmalska Anita Joanna , Tam Zhi Yang , Luo Weiwei , Kan Sophie , Viasnoff Virgile , Roca-Cusachs Pere , Tucker-Kellogg Lisa , Gauthier Nils C.
Published: July 2017

Cell migration is dependent on adhesion dynamics and actin cytoskeleton remodeling at the leading edge. These events may be physically constrained by the plasma membrane. Here, we show that the mechanical signal produced by an increase in plasma membrane tension triggers the positioning of new rows of adhesions at the leading edge. During protrusion, as membrane tension increases, velocity slows, and the lamellipodium buckles upward in a myosin II–independent manner. The buckling occurs between the front of the lamellipodium, where nascent adhesions are positioned in rows, and the base of the lamellipodium, where a vinculin-dependent clutch couples actin to previously positioned adhesions. As membrane tension decreases, protrusion resumes and buckling disappears, until the next cycle. We propose that the mechanical signal of membrane tension exerts upstream control in mechanotransduction by periodically compressing and relaxing the lamellipodium, leading to the positioning of adhesions at the leading edge of cells.
Tubulin glycylation controls primary cilia length
Authors: Gadadhar Sudarshan , Dadi Hala , Bodakuntla Satish , Schnitzler Anne , Bièche Ivan , Rusconi Filippo , Janke Carsten
Published: July 2017

As essential components of the eukaryotic cytoskeleton, microtubules fulfill a variety of functions that can be temporally and spatially controlled by tubulin posttranslational modifications. Tubulin glycylation has so far been mostly found on motile cilia and flagella, where it is involved in the stabilization of the axoneme. In contrast, barely anything is known about the role of glycylation in primary cilia because of limitations in detecting this modification in these organelles. We thus developed novel glycylation-specific antibodies with which we detected glycylation in many primary cilia. Glycylation accumulates in primary cilia in a length-dependent manner, and depletion or overexpression of glycylating enzymes modulates the length of primary cilia in cultured cells. This strongly suggests that glycylation is essential for the homeostasis of primary cilia, which has important implications for human disorders related to primary cilia dysfunctions, such as ciliopathies and certain types of cancer.
Tubulin isotype specificity in neuronal migration: Tuba8 can’t fill in for Tuba1a
Authors: Kawauchi Takeshi
Published: July 2017

Several tubulin isotypes, including Tuba1a, are associated with brain malformations. In this issue, Belvindrah et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201607074) show that Tuba1a and Tuba8 differentially regulate microtubule organization in neurons, and they provide insights into the mechanisms by which Tuba1a mutations disrupt adult mouse brain morphology.
Synaptotagmin isoforms confer distinct activation kinetics and dynamics to chromaffin cell granules
Authors: Rao Tejeshwar C. , Santana Rodriguez Zuleirys , Bradberry Mazdak M. , Ranski Alexandra H. , Dahl Peter J. , Schmidtke Michael W. , Jenkins Paul M. , Axelrod Daniel , Chapman Edwin R. , Giovannucci David R. , Anantharam Arun
Published: July 2017

Adrenomedullary chromaffin cells respond to sympathetic nervous system activation by secreting a cocktail of potent neuropeptides and hormones into the circulation. The distinct phases of the chromaffin cell secretory response have been attributed to the progressive fusion of distinct populations of dense core granules with different activation kinetics. However, it has been difficult to define what distinguishes these populations at the molecular level. Functional segregation of granule pools may depend on selective sorting of synaptotagmin-1 (Syt-1) and synaptotagmin-7 (Syt-7), which our previous work showed are rarely cosorted to the same granule. Here we assess the consequences of selective sorting of Syt isoforms in chromaffin cells, particularly with respect to granule dynamics and activation kinetics. Upon depolarization of cells expressing fluorescent Syt isoforms using elevated K+, we find that Syt-7 granules fuse with faster kinetics than Syt-1 granules, irrespective of stimulation strength. Pharmacological blockade of Ca2+ channels reveals differential dependence of Syt-1 versus Syt-7 granule exocytosis on Ca2+ channel subtypes. Syt-7 granules also show a greater tendency to fuse in clusters than Syt-1 granules, and granules harboring Syt-1 travel a greater distance before fusion than those with Syt-7, suggesting that there is spatial and fusion-site heterogeneity among the two granule populations. However, the greatest functional difference between granule populations is their responsiveness to Ca2+. Upon introduction of Ca2+ into permeabilized cells, Syt-7 granules fuse with fast kinetics and high efficacy, even at low Ca2+ levels (e.g., when cells are weakly stimulated). Conversely, Syt-1 granules require a comparatively larger increase in intracellular Ca2+ for activation. At Ca2+ concentrations above 30 µM, activation kinetics are faster for Syt-1 granules than for Syt-7 granules. Our study provides evidence for functional specialization of chromaffin cell granules via selective expression of Syt isoforms with different Ca2+ sensitivities.
Accessing the diffracted wavefield by coherent subtraction
Authors: Schwarz Benjamin , Gajewski Dirk
Published: July 2017

Diffractions have unique properties which are still rarely exploited in common practice. Aside from containing subwavelength information on the scattering geometry or indicating small-scale structural complexity, they provide superior illumination compared to reflections. While diffraction occurs arguably on all scales and in most realistic media, the respective signatures typically have low amplitudes and are likely to be masked by more prominent wavefield components. It has been widely observed that automated stacking acts as a directional filter favouring the most coherent arrivals. In contrast to other works, which commonly aim at steering the summation operator towards fainter contributions, we utilize this directional selection to coherently approximate the most dominant arrivals and subtract them from the data. Supported by additional filter functions which can be derived from wave front attributes gained during the stacking procedure, this strategy allows for a fully data-driven recovery of faint diffractions and makes them accessible for further processing. A complex single-channel field data example recorded in the Aegean sea near Santorini illustrates that the diffracted background wavefield is surprisingly rich and despite the absence of a high channel count can still be detected and characterized, suggesting a variety of applications in industry and academia.
Bounded Height in Families of Dynamical Systems
Authors: DeMarco Laura , Ghioca Dragos , Krieger Holly , Dang Nguyen Khoa , Tucker Thomas , Ye Hexi
Published: July 2017

Let $a,b\in\overline{\mathbb{Q}}$ be such that exactly one of $a$ and $b$ is an algebraic integer, and let $f_t(z):=z^2+t$ be a family of polynomials parameterized by $t\in\overline{\mathbb{Q}}$. We prove that the set of all $t\in\overline{\mathbb{Q}}$ for which there exist $m,n\geq 0$ such that $f_t^m(a)=f_t^n(b)$ has bounded height. This is a special case of a more general result supporting a new bounded height conjecture in arithmetic dynamics.