bluuebunny/crossref_metadata_2025 huggingface dataset:
High-accuracy current generation in the nanoampere regime from a silicon single-trap electron pump
Authors: Yamahata Gento , Giblin Stephen P. , Kataoka Masaya , Karasawa Takeshi , Fujiwara Akira
Published: March 2017

A gigahertz single-electron (SE) pump with a semiconductor charge island is promising for a future quantum current standard. However, high-accuracy current in the nanoampere regime is still difficult to achieve because the performance of SE pumps tends to degrade significantly at frequencies exceeding 1 GHz. Here, we demonstrate robust SE pumping via a single-trap level in silicon up to 7.4 GHz, at which the pumping current exceeds 1 nA. An accuracy test with an uncertainty of about one part per million (ppm) reveals that the pumping current deviates from the ideal value by only about 20 ppm at the flattest part of the current plateau. This value is two orders of magnitude better than the best one reported in the nanoampere regime. In addition, the pumping accuracy is almost unchanged up to 7.4 GHz, probably due to strong electron confinement in the trap. These results indicate that trap-mediated SE pumping is promising for achieving the practical operation of the quantum current standard.
Several microRNAs could predict survival in patients with hepatitis B-related liver cancer
Authors: Zhen Ye , Xinghui Zhao , Chao Wu , Yi Zhao , Jinwen Chen , Ruifang Gao , Chao Zhang , Min Zhao , Chunlei Guo , Yan Fang , Lingfang Du , Long Shen , Wenzhi Shen , Xiaohe Luo , Rong Xiang
Published: March 2017

MicroRNAs as biomarkers play an important role in the tumorigenesis process, including hepatocellular carcinomas (HCCs). In this paper, we used The Cancer Genome Atlas (TCGA) database to mine hepatitis B-related liver cancer microRNAs that could predict survival in patients with hepatitis B-related liver cancer. There were 93 cases of HBV-HCC and 49 cases of adjacent normal controls included in the study. Kaplan–Meier survival analysis of a liver cancer group versus a normal control group of differentially expressed genes identified eight genes with statistical significance. Compared with the normal liver cell line, hepatocellular carcinoma cell lines had high expression of 8 microRNAs, albeit at different levels. A Cox proportional hazards regression model for multivariate analysis showed that four genes had a significant difference. We established classification models to distinguish short survival time and long survival time of liver cancers. Eight genes (mir9-3, mir10b, mir31, mir519c, mir522, mir3660, mir4784, and mir6883) were identified could predict survival in patients with HBV-HCC. There was a significant correlation between mir10b and mir31 and clinical stages (p < 0.05). A random forests model effectively estimated patient survival times.
Cold-water marine natural products, 2006 to 2016
Authors: Soldatou Sylvia , Baker Bill J.
Published: March 2017

This is an update report on marine natural products isolated from cold-water organisms in the last decade, following the previous review that covered the literature up to 2005. Emphasis is on structural assignments and biological activity.
Synthesis, SAR and biological studies of sugar amino acid-based almiramide analogues: N-methylation leads the way
Authors: Das Dipendu , Khan Hina P. A. , Shivahare Rahul , Gupta Suman , Sarkar Jayanta , Siddiqui Mohd. Imran , Ampapathi Ravi Sankar , Chakraborty Tushar Kanti
Published: March 2017

The per-N-methylated sugar amino acid containing lipopeptides, analogous to almiramides, showed excellent antileishmanial activities.
Methyl-functionalized MoS2 nanosheets with reduced lattice breathing for enhanced pseudocapacitive sodium storage
Authors: Huang Lei , Wei Qiulong , Xu Xiaoming , Shi Changwei , Liu Xue , Zhou Liang , Mai Liqiang
Published: March 2017

Methyl-functionalized MoS2 (M-MoS2) nanosheets have been synthesized via a facile second solvothermal method.
Inclusion of lipopeptides into the DMPC lipid bilayers prevents Aβ peptide insertion
Authors: Parikh Niyati , Klimov Dmitri K.
Published: March 2017

Lipopeptides prevent penetration of Alzheimer's Aβ peptides into lipid bilayers.
A mitochondria-targetable fluorescent probe with a large Stokes shift for detecting hydrogen peroxide in aqueous solution and living cells
Authors: Liu Yong , Niu Jie , Nie Jing , Meng Fangfang , Lin Weiying
Published: March 2017

In this work, we introduce a carbazole-based fluorophore as a novel fluorescent dye for developing a mitochondria-targetable fluorescent probe with a large Stokes shift and it was used for detection of H2O2in aqueous solution and living cells.
Direct Csp2–H enolization: an allenoate alkylation cascade toward the assembly of multi-substituted furans
Authors: Bakshi Debanjan , Singh Anand
Published: March 2017

A new route toward tri- and tetrasubstituted furans has been realized via an allenoate alkylation pathway that employs the allenic moiety as a two-carbon unit in the construction of a furan scaffold.
cis or trans with class II diterpene cyclases
Authors: Jia Meirong , Peters Reuben J.
Published: March 2017

Isoprenoid precursors readily undergo (poly)cyclization in electrophilic reaction cascades, presumably as internal addition of the carbon–carbon double-bonds from neighboring isoprenyl repeats readily forms relatively stable cyclohexyl tertiary carbocation intermediates.
Nitrogen and sulfur co-doped chiral carbon quantum dots with independent photoluminescence and chirality
Authors: Hu Lulu , Sun Yue , Zhou Yunjie , Bai Liang , Zhang Yalin , Han Mumei , Huang Hui , Liu Yang , Kang Zhenhui
Published: March 2017

Chiral CQDs exhibit strong PL and outstanding enantioselective electrochemical recognition ability. Moreover, chiral CQDs possess independent PL and chiral properties.
The effect of maternal chromium status on lipid metabolism in female elderly mice offspring and involved molecular mechanism
Authors: Zhang Qian , Sun Xiaofang , Xiao Xinhua , Zheng Jia , Li Ming , Yu Miao , Ping Fan , Wang Zhixin , Qi Cuijuan , Wang Tong , Wang Xiaojing
Published: March 2017

Maternal malnutrition leads to the incidence of metabolic diseases in offspring. The purpose of this project was to examine whether maternal low chromium could disturb normal lipid metabolism in offspring, altering adipose cell differentiation and leading to the incidence of lipid metabolism diseases, including metabolic syndrome and obesity. Female C57BL mice were given a control diet (CD) or a low chromium diet (LCD) during the gestational and lactation periods. After weaning, offspring was fed with CD or LCD. The female offspring were assessed at 32 weeks of age. Fresh adipose samples from CD–CD group and LCD–CD group were collected. Genome mRNA were analysed using Affymetrix GeneChip Mouse Gene 2.0 ST Whole Transcript-based array. Differentially expressed genes (DEGs) were analysed based on gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis database. Maternal low chromium irreversibly increased offspring body weight, fat-pad weight, serum triglyceride (TG) and TNF-α. Eighty five genes increased and 109 genes reduced in the offspring adipose of the maternal low chromium group. According to KEGG pathway and String analyses, the PPAR signalling pathway may be the key controlled pathway related to the effect of maternal low chromium on female offspring. Maternal chromium status have long-term effects of lipid metabolism in female mice offspring. Normalizing offspring diet can not reverse these effects. The potential underlying mechanisms are the disturbance of the PPAR signalling pathway in adipose tissue.
Simple four‐quadrant grid‐tie control scheme with unity power factor rectifier mode for single‐phase DC/AC converters
Authors: Chi Pei‐Chin , Purnama Irwan , Hsieh Yao‐Ching , Lin Jing‐Yuan , Chiu Huang‐Jen
Published: March 2017

This study proposes a voltage‐oriented control scheme for four‐quadrant grid‐tie of a single‐phase bidirectional direct current/alternating current (AC) voltage‐sourced converter (VSC) to operate smartly at modes of unity power factor (PF) rectifier (UPFR), inverter or static var compensator. Given the possible harmonic‐distorted AC grid voltage, the proposed scheme follows or filters the grid voltage to generate the appropriate current command template for minimising the harmonic current while synchronising with the grid. The following template is for the UPFR mode, whereas the filtered template is for the other modes. The scheme proposes a unique band‐pass filter (BPF) to proceed with direct component generation for the filtered template. The proposed scheme further unifies the grid‐tie inductor current‐to‐voltage conversion for the following emplate and the quadrature component generation for the filtered template into a differentiator. The control laws under the filtered and following templates are derived. The BPF and differentiator designs are introduced. Simulations and experiments are conducted with a one‐cycle control full‐bridge VSC to verify the proposed grid‐tie control scheme and evaluate its performance.
Reduced graphene oxide@TiO2 nanorod@reduced graphene oxide hybrid nanostructures for photoelectrochemical hydrogen production
Authors: Wang Longlu , Li Yue , Liu Yutang
Published: March 2017

The optimised geometrical configuration between TiO2 nanorods (NRs) arrays and reduced graphene oxide (RGO) is essential for their application in catalysis of photoelectrochemical hydrogen production system. The scrupulous design of hierarchical nanoarchitectures by integration of multiple active materials can reinforce the light harvesting efficiency, enhance photocarrier generation and provide fast electron transport and efficient charge collection. Graphene film formed on the top surface and at the bottom of titanium dioxide nanorod (TiO2NRs) arrays were scrupulously fabricated in this paper. More importantly, the hydrogen production rate of RGO@TiO2NR@RGO hybrid nanostructures was up to 800 μmol/h−1 m2 (radiation intensity: 160 mW/cm2) which is over 2.5 times compared with bare TiO2NR.
A new transshipment policy in cluster supply chains based on system dynamics
Authors: Yan Bo , Liu Lifeng
Published: March 2017

In this paper, the cross-chain inventory emergency supplementary of two single supply chains is investigated to simulate the transshipment of the supply chain network system in the industrial cluster supply chains. We assume that each single supply chain is composed by a manufacturer, a wholesaler and a retailer. Besides, a new transshipment policy based on system dynamics (SD) is proposed in this paper, called the model of the cross-chain inventory transshipment between two enterprises from both the same tier and different tiers. The new proposed model is different from the model of the cross-chain inventory transshipment between two enterprises at the same tier and the model of the cross-chain inventory transshipment between two enterprises at different tiers, which have been researched by previous scholars. Some comparisons are made among the three models. It is proved that the new proposed model can improve the customer satisfaction level (CSL) and lower the total inventory level than the two other models existing currently.
An Extrapericardial Minimally Invasive Approach for Implantable Cardioverter Defibrillator
Authors: Madjarov Jeko , Poole Brad , Madzharov Svetozar , Fedor John , Robicsek Francis , Katz Michael
Published: March 2017

The indications for placement of an implantable cardioverter defibrillators (ICDs) have greatly expanded over the last years. However, standard transvenous approach is not suitable for a subset of patients who cannot benefit from ICD therapy. Here, we have demonstrated the feasibility and efficacy of extrapericardial ICD placement through a minimally invasive access in intact hearts as well as in postmyocardial infarction large animal models. Based on our data, we conclude that extrapericardial ICD placement is a feasible approach that may be a valuable alternative or adjunct to current defibrillator lead systems.
Role of Neuroimaging in Guiding Treatment Decisions on Endovascular Thrombectomy
Authors: Kaiser Daniel , Gerber Johannes , Puetz Volker
Published: March 2017

Six recent randomized controlled trials showed a significant benefit of endovascular therapy on patient outcome in acute ischemic stroke due to anterior cerebral artery occlusion. The positive results of these trials need to be implemented in clinical routine. Suitable patients should be evaluated for thrombectomy reliably and fast. All trials confirmed the role of pretherapeutic neuroimaging as crucial in selecting patients who can benefit from endovascular therapy. However, different approaches have been used, including imaging of the target vascular occlusion, infarct core, arterial collateral supply or the penumbra. In this review we discuss, in the context of the recent trials, the different methods of non-invasive neuroimaging and their role in decision-making for thrombectomy in acute ischemic stroke.
The future of research assessment in the humanities: bottom-up assessment procedures
Authors: Ochsner Michael , Hug Sven , Galleron Ioana
Published: March 2017

Research assessment in the social sciences and humanities (SSH) is delicate. Assessment procedures meet strong criticisms from SSH scholars and bibliometric research shows that the methods that are usually applied are ill-adapted to SSH research. While until recently research on assessment in the SSH disciplines focused on the deficiencies of the current assessment methods, we present some European initiatives that take a bottom-up approach. They focus on research practices in SSH and reflect on how to assess SSH research with its own approaches instead of applying and adjusting the methods developed for and in the natural and life sciences. This is an important development because we can learn from previous evaluation exercises that whenever scholars felt that assessment procedures were imposed in a top-down manner without proper adjustments to SSH research, it resulted in boycotts or resistance. Applying adequate evaluation methods not only helps foster a better valorization of SSH research within the research community, among policymakers and colleagues from the natural sciences, but it will also help society to better understand SSH’s contributions to solving major societal challenges. Therefore, taking the time to encourage bottom-up evaluation initiatives should result in being able to better confront the main challenges facing modern society. This article is published as part of a collection on the future of research assessment.
Investigation of an InP-based image converter with optical excitation
Authors: Song Y. , Cao L. , Peng B. D. , Song G. Z. , Yue Z. Q. , Ma J. M. , Sheng L. , Li B. K. , Wang H. X.
Published: March 2017

An image converter based on an indium phosphide has been developed to measure the two-dimensional spatial profile of the incident photon flux by probing the rapid change of the refractive index in the semiconductor. The spatial resolution, dynamic range, and temporal response of this image converter have been investigated with optical methods. The results show that the spatial resolution is ∼15 cycles/mm at the percent modulation transfer function of 0.5, the dynamic range is about 100, and the time response is in the order of 600 ps. This scheme can provide an alternative choice as an imaging diagnostic for experiments in the area of high-energy density physics.
On exceptional collections of line bundles and mirror symmetry for toric Del-Pezzo surfaces
Authors: Jerby Yochay
Published: March 2017

Let X be a toric Del-Pezzo surface and let Crit(W)⊂(ℂ*)n be the solution scheme of the Landau-Ginzburg system of equations. Denote by X° the polar variety of X. Our aim in this work is to describe a map L:Crit(W)→Fuktrop(X°) whose image under homological mirror symmetry corresponds to a full strongly exceptional collection of line bundles.
Vortex-antivortex pairs induced by curvature in toroidal nanomagnets
Authors: Vojkovic Smiljan , Carvalho-Santos Vagson L. , Fonseca Jakson M. , Nunez Alvaro S.
Published: March 2017

We show that the curvature of nanomagnets can be used to induce chiral textures in the magnetization field. Among the phenomena related to the interplay between the geometry and magnetic behavior of nanomagnets, an effective curvature-induced chiral interaction has been recently predicted. In this work, it is shown that magnetization configurations consisting of two structures with opposite winding numbers (vortex and antivortex) appear as remanent states in hollow toroidal nanomagnets. It is shown that these topological configurations are a result of a chiral interaction induced by curvature. In this way, the obtained results present a new form to produce stable vortices and antivortices by using nanomagnets with variable curvature.
Experimental and theoretical investigation of the vibrational band structure of the 1 Πu5−1 Πg5 high-spin system of C2
Authors: Bornhauser P. , Visser B. , Beck M. , Knopp G. , van Bokhoven J. A. , Marquardt R. , Radi P. P.
Published: March 2017

Vibrational levels of the recently observed high-spin transition (1 Πu5−1 Πg5) of dicarbon [P. Bornhauser et al., J. Chem. Phys. 142, 094313 (2015)] are explored by applying non-linear double-resonant four-wave mixing and laser-induced fluorescence methods. The deperturbation of the d Πg3, υ = 8 and 1 Πg5, υ = 3 states results in accurate molecular constants for the υ = 3 “dark” quintet state. In addition, the spin-orbit interaction constant is determined and parameters for the upper Swan level d Πg3, υ = 8 are improved. The first excited vibrational state of 1 Πu5 is observed by performing perturbation-assisted intersystem crossing via “gateway” states in the d Πg3, υ=6∼1 Πg5,υ= 0 system. The rotationally resolved spectra yield 11 transitions to 1 Πu5, υ = 1 that include four spin-substates. Data reduction results in accurate molecular constants of this vibrational level in the shallow potential energy surface of this state. Finally, υ = 1 and 2 of the lower quintet state (1 Πg5) are measured by performing perturbation-assisted double-resonant excitation to the 1 Πu5, υ = 0 state and observing dispersed fluorescence. The obtained molecular constants are compared with high level ab initio computations at the multi-reference configuration interaction (MRCI) level of theory by using a large correlation consistent basis set or, alternatively, by applying the computationally less demanding method of explicitly correlated multi-reference configuration interaction (MRCI-F12). The spectroscopic accuracy of both methods is evaluated by comparison with the experimental findings.
Tutorial: Reactive high power impulse magnetron sputtering (R-HiPIMS)
Authors: Anders André
Published: March 2017

High Power Impulse Magnetron Sputtering (HiPIMS) is a coating technology that combines magnetron sputtering with pulsed power concepts. By applying power in pulses of high amplitude and a relatively low duty cycle, large fractions of sputtered atoms and near-target gases are ionized. In contrast to conventional magnetron sputtering, HiPIMS is characterized by self-sputtering or repeated gas recycling for high and low sputter yield materials, respectively, and both for most intermediate materials. The dense plasma in front of the target has the dual function of sustaining the discharge and providing plasma-assistance to film growth, affecting the microstructure of growing films. Many technologically interesting thin films are compound films, which are composed of one or more metals and a reactive gas, most often oxygen or nitrogen. When reactive gas is added, non-trivial consequences arise for the system because the target may become “poisoned,” i.e., a compound layer forms on the target surface affecting the sputtering yield and the yield of secondary electron emission and thereby all other parameters. It is emphasized that the target state depends not only on the reactive gas' partial pressure (balanced via gas flow and pumping) but also on the ion flux to the target, which can be controlled by pulse parameters. This is a critical technological opportunity for reactive HiPIMS (R-HiPIMS). The scope of this tutorial is focused on plasma processes and mechanisms of operation and only briefly touches upon film properties. It introduces R-HiPIMS in a systematic, step-by-step approach by covering sputtering, magnetron sputtering, reactive magnetron sputtering, pulsed reactive magnetron sputtering, HiPIMS, and finally R-HiPIMS. The tutorial is concluded by considering variations of R-HiPIMS known as modulated pulsed power magnetron sputtering and deep-oscillation magnetron sputtering and combinations of R-HiPIMS with superimposed dc magnetron sputtering.
Symplectic time-average propagators for the Schrödinger equation with a time-dependent Hamiltonian
Authors: Blanes Sergio , Casas Fernando , Murua Ander
Published: March 2017

Several symplectic splitting methods of orders four and six are presented for the step-by-step time numerical integration of the Schrödinger equation when the Hamiltonian is a general explicitly time-dependent real operator. They involve linear combinations of the Hamiltonian evaluated at some intermediate points. We provide the algorithm and the coefficients of the methods, as well as some numerical examples showing their superior performance with respect to other available schemes.
The effect of symmetry on the U L3 NEXAFS of octahedral coordinated uranium(vi)
Authors: Bagus Paul S. , Nelin Connie J. , Ilton Eugene S.
Published: March 2017

We describe a detailed theoretical analysis of how distortions from ideal cubic or Oh symmetry to tetrahedral, D4h, symmetry affect the shape, in particular the width, of the U L3-edge NEXAFS for U(vi) in octahedral coordination. The full-width-half-maximum (FWHM) of the L3-edge white line decreases with increasing distortion from Oh symmetry. In particular, the FWHM of the white line narrows whether the tetragonal distortion is to compression or to extension. The origin of this decrease in the FWHM is analyzed in terms of the electronic structure of the excited levels arising from the unoccupied U(6d). The relative importance of ligand field and of spin-orbit effects is examined, where the dominant role of ligand field effects is established. Especially at higher distortions, the ligand splittings decrease rapidly and lead to an accelerated, quadratic decrease in the FWHM with increasing distortion. This is related to the increase of covalent character in the appropriate component of the Oh derived eg orbitals. Our ab initio theory uses relativistic wavefunctions for cluster models of the structures; empirical or semi-empirical parameters were not used to adjust prediction to experiment. A major advantage is that it provides a transparent approach for determining how the character and extent of the covalent mixing of the relevant U and O orbitals affect the U L3-edge white line.
Coexistence of low and high overlap phases in a supercooled liquid: An integral equation investigation
Authors: Bomont Jean-Marc , Pastore Giorgio , Hansen Jean-Pierre
Published: March 2017

The pair structure, free energy, and configurational overlap order parameter Q of an annealed system of two weakly coupled replicas of a supercooled “soft sphere” fluid are determined by solving the hypernetted-chain (HNC) and self-consistent Rogers-Young (RY) integral equations over a wide range of thermodynamic conditions ρ (number-density), T (temperature), and inter-replicas couplings ε12. Analysis of the resulting effective (or Landau) potential W(ρ,T; Q) and of its derivative with respect to Q confirms the existence of a “precursor transition” between weak and strong overlap phases below a critical temperature Tc well above the temperature To of the “ideal glass” transition observed in the limit ε12→0. The precursor transition is signalled by a loss of convexity of the potential W(Q) and by a concomitant discontinuity of the order parameter Q just below Tc, which crosses over to a mean-field-like van der Waals loop at lower temperatures. The HNC and RY equations lead to the same phase transition scenario, with quantitative differences in the predicted temperatures Tc and To.
Learning molecular energies using localized graph kernels
Authors: Ferré Grégoire , Haut Terry , Barros Kipton
Published: March 2017

Recent machine learning methods make it possible to model potential energy of atomic configurations with chemical-level accuracy (as calculated from ab initio calculations) and at speeds suitable for molecular dynamics simulation. Best performance is achieved when the known physical constraints are encoded in the machine learning models. For example, the atomic energy is invariant under global translations and rotations; it is also invariant to permutations of same-species atoms. Although simple to state, these symmetries are complicated to encode into machine learning algorithms. In this paper, we present a machine learning approach based on graph theory that naturally incorporates translation, rotation, and permutation symmetries. Specifically, we use a random walk graph kernel to measure the similarity of two adjacency matrices, each of which represents a local atomic environment. This Graph Approximated Energy (GRAPE) approach is flexible and admits many possible extensions. We benchmark a simple version of GRAPE by predicting atomization energies on a standard dataset of organic molecules.
A hybrid pulse combining topology utilizing the combination of modularized avalanche transistor Marx circuits, direct pulse adding, and transmission line transformer
Authors: Li Jiangtao , Zhao Zheng , Sun Yi , Liu Yuhao , Ren Ziyuan , He Jiaxin , Cao Hui , Zheng Minjun
Published: March 2017

Numerous applications driven by pulsed voltage require pulses to be with high amplitude, high repetitive frequency, and narrow width, which could be satisfied by utilizing avalanche transistors. The output improvement is severely limited by power capacities of transistors. Pulse combining is an effective approach to increase the output amplitude while still adopting conventional pulse generating modules. However, there are drawbacks in traditional topologies including the saturation tendency of combining efficiency and waveform oscillation. In this paper, a hybrid pulse combining topology was adopted utilizing the combination of modularized avalanche transistor Marx circuits, direct pulse adding, and transmission line transformer. The factors affecting the combining efficiency were determined including the output time synchronization of Marx circuits, and the quantity and position of magnetic cores. The numbers of the parallel modules and the stages were determined by the output characteristics of each combining method. Experimental results illustrated the ability of generating pulses with 2-14 kV amplitude, 7-11 ns width, and a maximum 10 kHz repetitive rate on a matched 50-300 Ω resistive load. The hybrid topology would be a convinced pulse combining method for similar nanosecond pulse generators based on the solid-state switches.
Self-powered narrowband p-NiO/n-ZnO nanowire ultraviolet photodetector with interface modification of Al2O3
Authors: Chen Zhao , Li Borui , Mo Xiaoming , Li Songzhan , Wen Jian , Lei Hongwei , Zhu Ziqiang , Yang Guang , Gui Pengbin , Yao Fang , Fang Guojia
Published: March 2017

All inorganic, self-powered, narrowband, and rapid response p-NiO/n-ZnO nanowire (NW) ultraviolet (UV) photodetectors were fabricated and investigated with Al2O3 as an interface modification layer. Al2O3 films grown by atomic layer deposition can greatly suppress the surface defects on ZnO NWs and improve the p-NiO/n-ZnO NW interface. The photo-response of the photodetector in the 430–500 nm wavelength range was greatly inhibited and the full-width at half-maximum of the response spectrum was less than 30 nm. A large responsivity of 1.4 mA/W was achieved under a 380 nm UV irradiation (0.36 mW/cm2) at zero bias and the response time of the device was less than 0.04 s. Such a simple interface modification method might promote the developing of ZnO NW based narrowband photodetectors.
Note: Design considerations and characterization of a flexible snapshot hyperspectral probe
Authors: Lim Hoong-Ta , Murukeshan Vadakke Matham
Published: March 2017

Hyperspectral imaging is a combination of imaging and spectroscopy to give detailed spectral information for each spatial point in the imaged scene. Using the concept of integral field spectroscopy, a custom fabricated two-dimensional to one-dimensional fiber bundle has recently been reported. It is used as a flexible snapshot hyperspectral probe, which can be used as an endoscope for biomedical applications. This paper reports on the design considerations of the fiber bundle as the flexible probe in the snapshot hyperspectral imaging system. The physical characterization of the custom fabricated fiber bundle and lateral resolution of the developed hyperspectral imaging system are also analyzed and described.
Emitter and absorber assembly for multiple self-dual operation and directional transparency
Authors: Kalozoumis P. A. , Morfonios C. V. , Kodaxis G. , Diakonos F. K. , Schmelcher P.
Published: March 2017

We demonstrate how to systematically design wave scattering systems with simultaneous coherent perfect absorbing and lasing operation at multiple and prescribed frequencies. The approach is based on the recursive assembly of non-Hermitian emitter and absorber units into self-dual emitter-absorber trimers at different composition levels, exploiting the simple structure of the corresponding transfer matrices. In particular, lifting the restriction to parity-time-symmetric setups enables the realization of emitter and absorber action at distinct frequencies and provides flexibility with respect to the choice of realistic parameters. We further show how the same assembled scatterers can be rearranged to produce unidirectional and bidirectional transparency at the selected frequencies. With the design procedure being generically applicable to wave scattering in single-channel settings, we demonstrate it with concrete examples of photonic multilayer setups.
Solution-processed gadolinium doped indium-oxide thin-film transistors with oxide passivation
Authors: Lee Seung-Hun , Kim Taehun , Lee Jihun , Avis Christophe , Jang Jin
Published: March 2017

We studied the effect of Gd doping on the structural properties of solution processed, crystalline In2O3 for thin-film transistor (TFT) application. With increasing Gd in In2O3 up to 20%, the material structure changes into amorphous phase, and the oxygen vacancy concentration decreases from 15.4 to 8.4%, and M-OH bonds from 33.5 to 23.7%. The field-effect mobility for the Gd doped In2O3 TFTs decreases and threshold voltage shifts to the positive voltage with increasing Gd concentration. In addition, the stability of the solution processed TFTs can also be improved by increasing Gd concentration. As a result, the optimum Gd concentration is found to be ∼5% in In2O3 and the 5% Gd doped In2O3 TFTs with the Y2O3 passivation layer exhibit the linear mobility of 9.74 cm2/V s, the threshold voltage of −0.27 V, the subthreshold swing of 79 mV/dec., and excellent bias stability.
All-optical switching in a continuously operated and strongly coupled atom-cavity system
Authors: Dutta Sourav , Rangwala S. A.
Published: March 2017

We experimentally demonstrate collective strong coupling, optical bi-stability (OB), and all-optical switching in a system consisting of ultracold 85Rb atoms, trapped in a dark magneto-optical trap (DMOT), and coupled to an optical Fabry-Perot cavity. The strong coupling is established by measuring the vacuum Rabi splitting (VRS) of a weak on-axis probe beam. The dependence of VRS on the probe beam power is measured, and bi-stability in the cavity transmission is observed. We demonstrate control over the transmission of the probe beam through the atom-cavity system using a free-space off-axis control beam and show that the cavity transmission can be switched on and off in micro-second timescales using micro-Watt control powers. The utility of the system as a tool for sensitive, in-situ and rapid measurements is envisaged.
Effect of thickness-dependent crystal mosaicity and chemical defect on electric properties in yttrium-stabilized epitaxial HfO2 thin films
Authors: Liu Wenlong , Liu Ming , Cheng Sheng , Zhang Ruyi , Ma Rong , Wang Hong
Published: March 2017

Epitaxial pseudo cubic yttrium-stabilized Y0.05Hf0.95O2 (YHO) thin films with bottom electrode layers of Pr0.5Sr0.5CoO3 were deposited on (001)-oriented LaAlO3 (LAO) substrates by using the pulsed laser deposition system. The crystal structure and thickness of the films were confirmed by θ–2θ scan and X-ray reflectivity via X-ray diffraction technology, respectively. Reciprocal space mapping (RSM) was performed to clarify the microstructure of the epitaxial YHO films affected by LAO substrates, and the result of symmetric RSMs revealed that the crystal mosaicity of the YHO films increases with the increasing film thicknesses. Moreover, the dominant conduction mechanisms of all the YHO films were ohmic conduction in the low electric field. At a high applied electric field, the YHO-5.4 nm film was determined by the space-charge-limited current behavior, while the samples of the YHO-9.8 nm and YHO-19.2 nm films were determined by ohmic conduction. The temperature-dependent I–V characteristics of the YHO films with different thicknesses have been also obtained, revealing that the current of all the YHO films generally increases with the increase in temperature, which attributed to the crystal mosaicity and chemical defects.
Structural and mixing characteristics influenced by streamwise vortices in supersonic flow
Authors: Zhang Dongdong , Tan Jianguo , Hou Juwei
Published: March 2017

By utilizing nanoparticle-based planar laser scattering method, the flow structures and mixing characteristics with the existence of large-scale streamwise vortices generated by a lobed mixer are investigated experimentally. The emergence and evolution of streamwise and spanwise vortices and the interaction between these two kinds of vortical structures are clearly exhibited. Fractal analysis reveals that streamwise vortices are strongly convoluted and possess complicated three-dimensional characteristics, which can favor molecular mixing. The turbulent/non-turbulent interface is obviously present, in which drastic turbulent entrainment occurs. Moreover, the emergence of typical T-shaped vortex suggests that this kind of vortex is a usual topological structure in turbulent transition region.
Influenza vaccine production technologies: past, present and future
Authors: Wen Yingxia , Settembre Ethan C
Published: March 2017

Influenza is a constantly evolving global health threat that leads to substantial morbidity and mortality particularly in vulnerable populations at either end of the age spectrum. Society has responded by creating a global public-private system that involves constant surveillance, candidate virus generation, and release reagent generation linked to worldwide influenza vaccine manufacturing capabilities. It was initially recognised that influenza circulates as multiple antigenically distinct subtypes, which led to the generation of vaccines containing multiple influenza strains. The first and still current major process used for influenza vaccine production is infection of embryonated hen's eggs with influenza virus. While this approach was a true advancement, some shortcomings such as lack of vaccine match to circulating strains due to egg adaptation and production capacity limitations have led to recent innovations in mammalian cell production and synthetic technologies aimed at further improving global influenza responses.
Sensing relative signal in the Tgf-β/Smad pathway
Authors: Frick Christopher L. , Yarka Clare , Nunns Harry , Goentoro Lea
Published: March 2017

Significance

It is not fully understood how cells process information in the face of noise. We posed this question in the transforming growth factor-β (Tgf-β) pathway, a major intercellular signaling pathway in animal cells. We found evidence that rather than sensing the signaling state of the Tgf-β pathway, cells sense the signaling state relative to background. Finding that signaling dynamics are interpreted in a relative manner may have implications for how we understand the pathway’s context-dependent outcomes and roles in diseases. Our work reinforces an emerging principle that individual cells process signal in a relative manner.
Allele-specific non-CG DNA methylation marks domains of active chromatin in female mouse brain
Authors: Keown Christopher L. , Berletch Joel B. , Castanon Rosa , Nery Joseph R. , Disteche Christine M. , Ecker Joseph R. , Mukamel Eran A.
Published: March 2017

Significance

Mammalian cells contain two copies of the genome inherited from the two parents. Although most genes are expressed using both, a small but critical part of the genome has different levels of expression from each copy. These parts include the X chromosome in females and imprinted genes in both genders, which play key roles in brain development and cognition. We measured gene expression and DNA methylation, an epigenetic modification of the genome, in the brains of mice using a technique that allowed us to analyze the maternal and paternal copies of the genome separately. Our findings show that a brain-specific form of DNA methylation called non-CG methylation marks regions of active transcription within the inactive X chromosome.
Deficiency of a sulfotransferase for sialic acid-modified glycans mitigates Alzheimer’s pathology
Authors: Zhang Zui , Takeda-Uchimura Yoshiko , Foyez Tahmina , Ohtake-Niimi Shiori , Narentuya  , Akatsu Hiroyasu , Nishitsuji Kazuchika , Michikawa Makoto , Wyss-Coray Tony , Kadomatsu Kenji , Uchimura Kenji
Published: March 2017

Significance

Keratan sulfate (KS) is an extracellular sulfated glycan covalently attached to core proteins in the brain. Here, we show that a type of KS with a certain molecular mass in microglia and its synthetic enzyme GlcNAc6ST1, previously known as a sulfotransferase for ligands of L-selectin, are upregulated in model mice and patients with Alzheimer’s disease. GlcNAc6ST1 deficiency resulted in increased amyloid-β phagocytosis and hyperresponsiveness to an antiinflammatory cytokine in primary microglia. Moreover, amyloid-β pathology was mitigated in GlcNAc6ST1-deficient Alzheimer’s model mice. These data support a model in which GlcNAc6ST1 regulates microglial functions via synthesizing sialic acid-modified KS, a potential ligand for microglial carbohydrate-recognizing receptors, in Alzheimer’s pathology.
Activin-A co-opts IRF4 and AhR signaling to induce human regulatory T cells that restrain asthmatic responses
Authors: Tousa Sofia , Semitekolou Maria , Morianos Ioannis , Banos Aggelos , Trochoutsou Aikaterini I. , Brodie Tess M. , Poulos Nikolaos , Samitas Konstantinos , Kapasa Maria , Konstantopoulos Dimitris , Paraskevopoulos Giannis , Gaga Mina , Hawrylowicz Catherine M. , Sallusto Federica , Xanthou Georgina
Published: March 2017

Type 1 regulatory T (Tr1) cells play a pivotal role in restraining human T-cell responses toward environmental allergens and protecting against allergic diseases. Still, the precise molecular cues that underlie their transcriptional and functional specification remain elusive. Here, we show that the cytokine activin-A instructs the generation of CD4
+
T cells that express the Tr1-cell–associated molecules IL-10, inducible T-Cell costimulator (ICOS), lymphocyte activation gene 3 protein (LAG-3), and CD49b, and exert strongly suppressive functions toward allergic responses induced by naive and in vivo-primed human T helper 2 cells. Moreover, mechanistic studies reveal that activin-A signaling induces the activation of the transcription factor interferon regulatory factor (IRF4), which, along with the environmental sensor aryl hydrocarbon receptor, forms a multipartite transcriptional complex that binds in IL-10 and ICOS promoter elements and controls gene expression in human CD4
+
T cells. In fact, IRF4 silencing abrogates activin-A–driven
IL10
and
ICOS
up-regulation and impairs the suppressive functions of human activin-A–induced Tr1-like (act-A–iTr1) cells. Importantly, using a humanized mouse model of allergic asthma, we demonstrate that adoptive transfer of human act-A–iTr1 cells, both in preventive and therapeutic protocols, confers significant protection against cardinal asthma manifestations, including pulmonary inflammation. Overall, our findings uncover an activin-A–induced IRF4-aryl hydrocarbon receptor (AhR)–dependent transcriptional network, which generates suppressive human Tr1 cells that may be harnessed for the control of allergic diseases.
Highly oriented photosynthetic reaction centers generate a proton gradient in synthetic protocells
Authors: Altamura Emiliano , Milano Francesco , Tangorra Roberto R. , Trotta Massimo , Omar Omar Hassan , Stano Pasquale , Mavelli Fabio
Published: March 2017

Significance

The photosynthetic reaction center (RC), an integral membrane protein at the core of bioenergetics of all autotrophic organisms, has been reconstituted in the membrane of giant unilamellar vesicles (RC@GUV) by retaining the physiological orientation at a very high percentage (90 ± 1%). Owing to this uniform orientation, it has been possible to demonstrate that, under red-light illumination, photosynthetic RCs operate as nanoscopic machines that convert light energy into chemical energy, in the form of a proton gradient across the vesicle membrane. This result is of great relevance in the field of synthetic cell construction, proving that such systems can easily transduce light energy into chemical energy eventually exploitable for the synthesis of ATP.
Negative allosteric regulation of
Enterococcus faecalis
small alarmone synthetase RelQ by single-stranded RNA
Authors: Beljantseva Jelena , Kudrin Pavel , Andresen Liis , Shingler Victoria , Atkinson Gemma C. , Tenson Tanel , Hauryliuk Vasili
Published: March 2017

Significance

Bacteria regulate their intracellular environment through two ubiquitous posttranscriptional regulatory mechanisms: enzymatic synthesis of small signaling molecules that allosterically regulate protein targets, and complex formation of RNA-binding proteins with target RNAs. We show that these two mechanisms can be combined within a single protein. The small alarmone synthetase RelQ from the Gram-positive pathogen
Enterococcus faecalis
enzymatically regulates the levels of alarmone nucleotide (p)ppGpp, a key regulator of stress adaptation, pathogenicity, and antibiotic tolerance. In its other role as an RNA-binding protein, RelQ interacts with single-stranded RNA in a sequence-specific manner. Because (p)ppGpp synthesis and pppGpp binding are mutually incompatible with RelQ:RNA complex formation, the RelQ:RNA interaction acts as a regulatory switch between inactive and active forms of the enzyme.
EGF and NRG induce phosphorylation of HER3/ERBB3 by EGFR using distinct oligomeric mechanisms
Authors: van Lengerich Bettina , Agnew Christopher , Puchner Elias M. , Huang Bo , Jura Natalia
Published: March 2017

Significance

Signaling by human epidermal growth factor receptor (HER) receptors relies on heteromeric interactions between four members of the family: EGF receptor, HER2, HER3, and HER4. These interactions remain remarkably poorly understood. Using super-resolution microscopy imaging and signaling assays, we demonstrate a rich scope of HER receptor organization patterns that are differentially influenced by ligands and coreceptor expression, resulting in unique phosphorylation signatures of HER receptors. We also show that there are fundamental differences in molecular mechanisms that govern HER receptor cross-activation, which do not always follow the canonical kinase dimerization mechanism. Our data underscore an emerging concept in the field that HER receptor signaling needs to be interpreted in the context of higher-order receptor oligomers, redefining the basic signaling unit relevant for receptor function.
Experimental evidence that parasites drive eco-evolutionary feedbacks
Authors: Brunner Franziska S. , Anaya-Rojas Jaime M. , Matthews Blake , Eizaguirre Christophe
Published: March 2017

Significance

Anthropogenic effects on the environment are ubiquitous and have enormous impacts on individual and ecosystem health. It is widely accepted that environmental change affects disease distribution, but how it may affect parasite-driven evolution remains elusive. Our results provide experimental evidence that parasites play a major role in ecosystem dynamics and, as a result, can affect selection in subsequent host generations. This role is further modified by the prevailing environmental conditions that affect disease dynamics in two ways: through altered ecological opportunities for disease and through altered evolutionary effects on the host.
Cerberus–Nodal–Lefty–Pitx signaling cascade controls left
–
right asymmetry in amphioxus
Authors: Li Guang , Liu Xian , Xing Chaofan , Zhang Huayang , Shimeld Sebastian M. , Wang Yiquan
Published: March 2017

Significance

Some bilaterally symmetrical animals show genetically programmed differences between their left and right sides, for example the placement of the heart and viscera in humans and other vertebrates. We dissect the regulation of this in embryos of amphioxus, a close relative of vertebrates that develops extraordinary asymmetries as a larva. We demonstrate a system in which asymmetric expression of the signal gene
Noda
l
is controlled by positive and negative feedback loops with its own inhibitors. When this system is disrupted, embryos develop mirror-image symmetry with two “left” sides or two “right” sides. Comparison with other animals shows how this complex regulatory mechanism has evolved by addition of new feedback regulation to a more ancient signaling interaction.
Conformational dynamics and role of the acidic pocket in ASIC pH-dependent gating
Authors: Vullo Sabrina , Bonifacio Gaetano , Roy Sophie , Johner Niklaus , Bernèche Simon , Kellenberger Stephan
Published: March 2017

Significance

Many physiological processes are regulated by pH. The acid-sensing ion channels (ASICs) are neuronal pH sensors involved in learning, fear behavior, neurodegeneration after ischemic stroke, and pain sensation. The mechanism by which acidic pH activates ASICs is still poorly understood. We show here that the “acidic pocket,” the binding site of several toxins, is not essential for channel function but has, rather, a modulatory role. Furthermore, we describe the structural rearrangements occurring in this domain during ASIC activity, and highlight the importance of the “palm” domain in channel opening and current decay. In this study, we provide insights on the molecular mechanisms controlling ASIC activity together with a rational basis for the development of ASIC-targeting drugs.
Data-based modeling of drug penetration relates human skin barrier function to the interplay of diffusivity and free-energy profiles
Authors: Schulz Robert , Yamamoto Kenji , Klossek André , Flesch Roman , Hönzke Stefan , Rancan Fiorenza , Vogt Annika , Blume-Peytavi Ulrike , Hedtrich Sarah , Schäfer-Korting Monika , Rühl Eckart , Netz Roland R.
Published: March 2017

Significance

Human skin consists of distinct layers and is designed to prevent water loss and to keep harmful materials out, which makes transcutaneous drug delivery challenging. A model for drug diffusion within skin is introduced that as the only input requires experimental concentration profiles measured at three distinct penetration times. For the specific example of the antiinflammatory drug dexamethasone, the modeling shows that both free-energy and diffusivity profiles are highly inhomogeneous, which reveals the basic mechanism of epidermal barrier function: slow diffusion in the outer stratum corneum hinders fast penetration into the skin, whereas a pronounced free-energy step from the epidermis to the dermis underneath reduces long-time permeation. Targeted drug delivery strategies through skin must reflect these properties.