bluuebunny/crossref_metadata_2025 huggingface dataset:
Fractional Solitons in Excitonic Josephson Junctions
Authors: Hsu Ya-Fen , Su Jung-Jung
Published: October 2015

The Josephson effect is especially appealing to physicists because it reveals macroscopically the quantum order and phase. In excitonic bilayers the effect is even subtler due to the counterflow of supercurrent as well as the tunneling between layers (interlayer tunneling). Here we study, in a quantum Hall bilayer, the excitonic Josephson junction: a conjunct of two exciton condensates with a relative phase ϕ0 applied. The system is mapped into a pseudospin ferromagnet then described numerically by the Landau-Lifshitz-Gilbert equation. In the presence of interlayer tunneling, we identify a family of fractional sine-Gordon solitons which resemble the static fractional Josephson vortices in the extended superconducting Josephson junctions. Each fractional soliton carries a topological charge Q that is not necessarily a half/full integer but can vary continuously. The calculated current-phase relation (CPR) shows that solitons with Q = ϕ0/2π is the lowest energy state starting from zero ϕ0 – until ϕ0 > π – then the alternative group of solitons with Q = ϕ0/2π − 1 takes place and switches the polarity of CPR.
NMR characterization of HIV-1 reverse transcriptase binding to various non-nucleoside reverse transcriptase inhibitors with different activities
Authors: Thammaporn Ratsupa , Yagi-Utsumi Maho , Yamaguchi Takumi , Boonsri Pornthip , Saparpakorn Patchreenart , Choowongkomon Kiattawee , Techasakul Supanna , Kato Koichi , Hannongbua Supa
Published: October 2015

Human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT) is an important target for antiviral therapy against acquired immunodeficiency syndrome. However, the efficiency of available drugs is impaired most typically by drug-resistance mutations in this enzyme. In this study, we applied a nuclear magnetic resonance (NMR) spectroscopic technique to the characterization of the binding of HIV-1 RT to various non-nucleoside reverse transcriptase inhibitors (NNRTIs) with different activities, i.e., nevirapine, delavirdine, efavirenz, dapivirine, etravirine and rilpivirine. 1H-13C heteronuclear single-quantum coherence (HSQC) spectral data of HIV-1 RT, in which the methionine methyl groups of the p66 subunit were selectively labeled with 13C, were collected in the presence and absence of these NNRTIs. We found that the methyl 13C chemical shifts of the M230 resonance of HIV-1 RT bound to these drugs exhibited a high correlation with their anti-HIV-1 RT activities. This methionine residue is located in proximity to the NNRTI-binding pocket but not directly involved in drug interactions and serves as a conformational probe, indicating that the open conformation of HIV-1 RT was more populated with NNRTIs with higher inhibitory activities. Thus, the NMR approach offers a useful tool to screen for novel NNRTIs in developing anti-HIV drugs.
Correction: Corrigendum: Ursolic acid exerts anti-cancer activity by suppressing vaccinia-related kinase 1-mediated damage repair in lung cancer cells
Authors: Kim Seong-Hoon , Ryu Hye Guk , Lee Juhyun , Shin Joon , Harikishore Amaravadhi , Jung Hoe-Yune , Seul Kim Ye , Lyu Ha-Na , Oh Eunji , Baek Nam-In , Choi Kwan-Yong , Sup Yoon Ho , Kim Kyong-Tai
Published: October 2015

Many mitotic kinases have been targeted for the development of anti-cancer drugs, and inhibitors of these kinases have been expected to perform well for cancer therapy. Efforts focused on selecting good targets and finding specific drugs to target are especially needed, largely due to the increased frequency of anti-cancer drugs used in the treatment of lung cancer. Vaccinia-related kinase 1 (VRK1) is a master regulator in lung adenocarcinoma and is considered a key molecule in the adaptive pathway, which mainly controls cell survival. We found that ursolic acid (UA) inhibits the catalytic activity of VRK1 via direct binding to the catalytic domain of VRK1. UA weakens surveillance mechanisms by blocking 53BP1 foci formation induced by VRK1 in lung cancer cells, and possesses synergistic anti-cancer effects with DNA damaging drugs. Taken together, UA can be a good anti-cancer agent for targeted therapy or combination therapy with DNA damaging drugs for lung cancer patients.
Correction: Corrigendum: Decreased LKB1 predicts poor prognosis in Pancreatic Ductal Adenocarcinoma
Authors: Yang Jian-Yu , Jiang Shu-Heng , Liu De-Jun , Yang Xiao-Mei , Huo Yan-Miao , Li Jiao , Hua Rong , Zhang Zhi-Gang , Sun Yong-Wei
Published: October 2015

Liver kinase B1 (LKB1) has been identified as a critical modulator involved in cell proliferation and polarity. The purpose of the current study was to characterize the expression pattern of LKB1 and assess the clinical significance of LKB1 expression in pancreatic ductal adenocarcinoma (PDAC) patients. LKB1 mRNA expression which was analyzed in 32 PDAC lesions and matched non-tumor tissues, was downregulated in 50% (16/32) of PDAC lesions. Similar results were also obtained by analyzing three independent datasets from Oncomine. Protein expression of LKB1 was significantly reduced in 6 PDAC cell lines and downregulated in 31.3% (10/32) of PDAC lesions compared to matched non-tumorous tissues, as determined by Western blot analysis. Additionally, tissue microarray containing 205 PDAC specimens was evaluated for LKB1 expression by IHC and demonstrated that reduced expression of LKB1 in 17.6% (36/205) of PDAC tissues was significantly correlated with clinical stage, T classification, N classification, liver metastasis and vascular invasion. Importantly, Kaplan-Meier survival and Cox regression analyses were executed to evaluate the prognosis of PDAC and found that LKB1 protein expression was one of the independent prognostic factors for overall survival of PDAC patients.
Differential temporal changes of primary and secondary bacterial symbionts and whitefly host fitness following antibiotic treatments
Authors: Zhang Chang-Rong , Shan Hong-Wei , Xiao Na , Zhang Fan-Di , Wang Xiao-Wei , Liu Yin-Quan , Liu Shu-Sheng
Published: October 2015

Where multiple symbionts coexist in the same host, the selective elimination of a specific symbiont may enable the roles of a given symbiont to be investigated. We treated the Mediterranean species of the whitefly Bemisia tabaci complex by oral delivery of the antibiotic rifampicin and then examined the temporal changes of its primary symbiont “Candidatus Portiera aleyrodidarum” and secondary symbiont “Ca. Hamiltonella defensa” as well as host fitness for three generations. In adults treated with rifampicin (F0), the secondary symbiont was rapidly reduced, approaching complete disappearance as adults aged. In contrast, the primary symbiont was little affected until later in the adult life. In the offspring of these adults (F1), both symbionts were significantly reduced and barely detectable when the hosts reached the adult stage. The F1 adults laid few eggs (F2), all of which failed to hatch. Mating experiments illustrated that the negative effects of rifampicin on host fitness were exerted via female hosts but not males. This study provides the first evidence of differential temporal reductions of primary and secondary symbionts in whiteflies following an antibiotic treatment. Studies that disrupt functions of bacterial symbionts must consider their temporal changes.
Electrical stimulation of non-classical photon emission from diamond color centers by means of sub-superficial graphitic electrodes
Authors: Forneris Jacopo , Traina Paolo , Monticone Daniele Gatto , Amato Giampiero , Boarino Luca , Brida Giorgio , Degiovanni Ivo P. , Enrico Emanuele , Moreva Ekaterina , Grilj Veljko , Skukan Natko , Jakšić Milko , Genovese Marco , Olivero Paolo
Published: October 2015

Focused MeV ion beams with micrometric resolution are suitable tools for the direct writing of conductive graphitic channels buried in an insulating diamond bulk, as already demonstrated for different device applications. In this work we apply this fabrication method to the electrical excitation of color centers in diamond, demonstrating the potential of electrical stimulation in diamond-based single-photon sources. Differently from optically-stimulated light emission from color centers in diamond, electroluminescence (EL) requires a high current flowing in the diamond subgap states between the electrodes. With this purpose, buried graphitic electrode pairs, 10 μm spaced, were fabricated in the bulk of a single-crystal diamond sample using a 6 MeV C microbeam. The electrical characterization of the structure showed a significant current injection above an effective voltage threshold of 150 V, which enabled the stimulation of a stable EL emission. The EL imaging allowed to identify the electroluminescent regions and the residual vacancy distribution associated with the fabrication technique. Measurements evidenced isolated electroluminescent spots where non-classical light emission in the 560–700 nm spectral range was observed. The spectral and auto-correlation features of the EL emission were investigated to qualify the non-classical properties of the color centers.
Doxycycline hinders phenylalanine fibril assemblies revealing a potential novel therapeutic approach in phenylketonuria
Authors: De Luigi Ada , Mariani Alessandro , De Paola Massimiliano , Re Depaolini Andrea , Colombo Laura , Russo Luca , Rondelli Valeria , Brocca Paola , Adler-Abramovich Lihi , Gazit Ehud , Del Favero Elena , Cantù Laura , Salmona Mario
Published: October 2015

A new paradigm for the aetiopathology of phenylketonuria suggests the presence of amyloid-like assemblies in the brains of transgenic mouse models and patients with phenylketonuria, possibly shedding light on the selective cognitive deficit associated with this disease. Paralleling the amyloidogenic route that identifies different stages of peptide aggregation, corresponding to different levels of toxicity, we experimentally address for the first time, the physico-chemical properties of phenylalanine aggregates via Small Angle, Wide Angle X-ray Scattering and Atomic Force Microscopy. Results are consistent with the presence of well-structured, aligned fibres generated by milliMolar concentrations of phenylalanine. Moreover, the amyloid-modulating doxycycline agent affects the local structure of phenylalanine aggregates, preventing the formation of well-ordered crystalline structures. Phenylalanine assemblies prove toxic in vitro to immortalized cell lines and primary neuronal cells. Furthermore, these assemblies also cause dendritic sprouting alterations and synaptic protein impairment in neurons. Doxycycline counteracts these toxic effects, suggesting an approach for the development of future innovative non-dietary preventive therapies.
LFP-guided targeting of a cortical barrel column for in vivo two-photon calcium imaging
Authors: Lee Joon-Hyuk , Shin Hee-Sup , Lee Kwang-Hyung , Chung Sooyoung
Published: October 2015

Two-photon microscopy of bulk-loaded functional dyes is an outstanding physiological technique that enables simultaneous functional mapping of hundreds of brain cells in vivo at single-cell resolution. However, precise targeting of a specific cortical location is not easy due to its fine dimensionality. To enable precise targeting, intrinsic-signal optical imaging is often additionally performed. However, the intrinsic-signal optical imaging is not only time-consuming but also ineffective in ensuring precision. Here, we propose an alternative method for precise targeting based on local field potential (LFP) recording, a conventional electrophysiological method. The heart of this method lies in use of the same glass pipette to record LFPs and to eject calcium dye. After confirming the target area by LFP using a glass pipette, the calcium dye is ejected from the same pipette without a time delay or spatial adjustment. As a result, the calcium dye is loaded into the same ensemble of brain cells from which the LFP was obtained. As a validation of the proposed LFP-based method, we targeted and successfully loaded calcium dye into layer 2/3 of a mouse barrel column.
Printing Highly Controlled Suspended Carbon Nanotube Network on Micro-patterned Superhydrophobic Flexible Surface
Authors: Li Bo , Wang Xin , Jung Hyun Young , Kim Young Lae , Robinson Jeremy T. , Zalalutdinov Maxim , Hong Sanghyun , Hao Ji , Ajayan Pulickel M. , Wan Kai-Tak , Jung Yung Joon
Published: October 2015

Suspended single-walled carbon nanotubes (SWCNTs) offer unique functionalities for electronic and electromechanical systems. Due to their outstanding flexible nature, suspended SWCNT architectures have great potential for integration into flexible electronic systems. However, current techniques for integrating SWCNT architectures with flexible substrates are largely absent, especially in a manner that is both scalable and well controlled. Here, we present a new nanostructured transfer paradigm to print scalable and well-defined suspended nano/microscale SWCNT networks on 3D patterned flexible substrates with micro- to nanoscale precision. The underlying printing/transfer mechanism, as well as the mechanical, electromechanical and mechanical resonance properties of the suspended SWCNTs are characterized, including identifying metrics relevant for reliable and sensitive device structures. Our approach represents a fast, scalable and general method for building suspended nano/micro SWCNT architectures suitable for flexible sensing and actuation systems.
Synthesis, characterization, and electronic structures of a methyl germyliumylidene ion and germylone-group VI metal complexes
Authors: Su Bochao , Ganguly Rakesh , Li Yongxin , Kinjo Rei
Published: October 2015

The reaction of germylone (L)Ge (1) [L = 3-Ad-1-{C(tBu) = N(Mes)}C3H4N2] with 1 equivalent of MeOTf afforded a germyliumylidene ion [(L)GeMe]+OTf− (2), while reactions with M(CO)5(thf) (M = Cr, Mo, W) gave the corresponding germylone-metal complexes [(L)Ge]M(CO)5 (3–5).
The luminescence properties of the heteroleptic [Re(CO)3(N∩N)Cl] and [Re(CO)3(N∩N)(CH3CN)]+ complexes in view of the combined Marcus–Jortner and Mulliken–Hush formalism
Authors: Woźna Agnieszka , Kapturkiewicz Andrzej
Published: October 2015

Unified description of the radiative kr and non-radiative knr rate constants characterizing the 3*MLCT → S0 processes allows deeper insights into the luminescence properties of the heteroleptic [Re(CO)3(α-diimine)(CH3CN)]+ and [Re(CO)3(α-diimine)Cl] chelates.
Computer-assisted designed “selenoxy–chinolin”: a new catalytic mechanism of the GPx-like cycle and inhibition of metal-free and metal-associated Aβ aggregation
Authors: Wang Zhiren , Wang Yali , Li Wenrui , Liu Zhihong , Luo Zonghua , Sun Yang , Wu Ruibo , Huang Ling , Li Xingshu
Published: October 2015

Using support from rational computer-assisted design, a novel series of hybrids designed by fusing the metal-chelating agent CQ and the antioxidant ebselen were synthesized and evaluated as multitarget-directed ligands.
Selective transformation of hemicellulose (xylan) into n-pentane, pentanols or xylitol over a rhenium-modified iridium catalyst combined with acids
Authors: Liu Sibao , Okuyama Yasuyo , Tamura Masazumi , Nakagawa Yoshinao , Imai Akio , Tomishige Keiichi
Published: October 2015

n-Pentane (yield 70%), pentanols (32%) or xylitol (79%) can be produced from xylan by using an Ir–ReOx/SiO2 catalyst combined with acids.
Solution-based synthesis and purification of zinc tin phosphide nanowires
Authors: Sheets Erik J. , Balow Robert B. , Yang Wei-Chang , Stach Eric A. , Agrawal Rakesh
Published: October 2015

The solution-based synthesis of nanoscale earth-abundant semiconductors has the potential to unlock simple, scalable, and tunable material processes which currently constrain development of novel compounds for alternative energy devices.
Au25cluster functionalized metal–organic nanostructures for magnetically targeted photodynamic/photothermal therapy triggered by single wavelength 808 nm near-infrared light
Authors: Yang Dan , Yang Guixin , Gai Shili , He Fei , An Guanghui , Dai Yunlu , Lv Ruichan , Yang Piaoping
Published: October 2015

Metal–organic frameworks (MOFs) of Fe3O4/ZIF-8-Au25were synthesized by a green and economic procedure, and exhibited high anti-cancer therapeutic efficacy for combined photodynamic and photothermal therapy.
The size-dependent morphology of Pd nanoclusters formed by gas condensation
Authors: Pearmain D. , Park S. J. , Abdela A. , Palmer R. E. , Li Z. Y.
Published: October 2015

A scanning transmission electron microscopy (STEM) study of mass-selected Pd nanoclusters in the size range of 887 to 10 000 atoms, formed by inert gas aggregation, reveals a strong size-dependence of cluster morphology.
Copper-catalyzed electrophilic amination using N-methoxyamines
Authors: Fukami Yutaro , Wada Takamasa , Meguro Tatsuhiko , Chida Noritaka , Sato Takaaki
Published: October 2015

Copper-catalyzed electrophilic amination using functionalizedN-methoxyamines, prepared by nucleophilic addition toN-methoxyamides, is reported.
β-Xylopyranosides: synthesis and applications
Authors: Brusa Charlotte , Muzard Murielle , Rémond Caroline , Plantier-Royon Richard
Published: October 2015

In recent years, β-xylopyranosides have attracted interest due to the development of biomass-derived molecules. This review focuses on general routes for the preparation of β-xylopyranosides by chemical and enzymatic pathways and their main uses.
Study on identification of rice seeds by chemical oscillation fingerprints
Authors: Li Guangyu , Li Yongling , Zhang Mingxiao
Published: October 2015

A B–Z oscillation reaction can be maintained for several hours without interference from foreign substances. The oscillation reaction process changed when a sample was added, and a characteristic fingerprint was obtained.
Study on the preparation and photocatalytic oxidation properties of TiO2/nano-Fe0 photocatalysts
Authors: Dong Yeshuo , Fei Xuening , Cao Lingyun , Wu Rilei , Jiang Yuanguang
Published: October 2015

TiO2/nano-Fe0 composite photocatalysts were prepared via a liquid phase reduction deposition method using anatase nano-TiO2 as a deposition substrate.
Facile synthesis of well-dispersed CeO2–CuOx composite hollow spheres with superior catalytic activity for CO oxidation
Authors: Zhang Jian , Gong Ming , Cao Yidan , Wang Chang-An
Published: October 2015

Well-dispersed CeO2–CuOx composite hollow spheres have been successfully synthesized through a facile reflux method using carbon spheres as sacrificial templates.
Dispersing Pt and Pd atoms on Au nanoparticles deposited on n-GaN substrates for formic acid oxidation
Authors: Qin S.-J. , Zhao Y. , Peng F. , Chen X.-Q. , Pan G.-B.
Published: October 2015

Au nanoparticles, with dispersed Pt and Pd atoms on them, supported on n-GaN substrates were prepared. The catalysts showed an enhanced performance for formic acid oxidation, and the mass activity reached 3.5 mA μgPtPd−1.
Constant pH molecular dynamics study on the doubly mutated staphylococcal nuclease: capturing the microenvironment
Authors: Pathak Arup Kumar
Published: October 2015

Small rearrangements of residues in the microenvironment of V23E/L36K variant of staphylococcal nuclease can effectively be captured by CpHMD method.
Supramolecular nanoparticles constructed by balancing the forces between attractive host–guest and repulsive electrostatic interactions in two positively charged polymers
Authors: Zhuang Yue-Zhu , Gu Wen-Xing , Yang Jin-Jun , Chen XiYi , Gao Hui
Published: October 2015

A novel type of supramolecular nanoparticle (SNP) was self-assembled based on the balance of forces including attractive supramolecular host–guest interactions and repulsive electrostatic interactions between the host and the guest polymers.
Formulation characteristics of triacylglycerol oil-in-water emulsions loaded with ergocalciferol using microchannel emulsification
Authors: Khalid Nauman , Kobayashi Isao , Wang Zheng , Neves Marcos A. , Uemura Kunihiko , Nakajima Mitsutoshi , Nabetani Hiroshi
Published: October 2015

Food grade monodisperse O/W emulsions encapsulating ergocalciferol have been formulated using microchannel emulsification. The O/W emulsion droplets have an encapsulation efficiency of over 75% within the evaluated storage period.
A molybdovanadophosphate-based surfactant encapsulated heteropolyanion with multi-lamellar nano-structure for catalytic wet air oxidation of organic pollutants under ambient conditions
Authors: Lua Shun Kuang , Oh Wen-Da , Zhang Li-Zhi , Yao Lei , Lim Teik-Thye , Dong ZhiLi
Published: October 2015

Molybdovanadophosphate-based surfactant encapsulated heteropolyanion with multi-lamellar nano-structure for ambient catalytic wet air oxidation of BPA.
A computational study to unravel the selectivity in an iron-catalysed [3 + 2] cycloaddition of aziridine and heterocumulenes
Authors: Adhikari Debashis
Published: October 2015

The reaction mechanism of cycloaddition between phenyl aziridine and heterocumulene catalysed by iron salts in water has been modeled computationally to trace the origin of excellent regioselectivity toward 5-substituted product formation.
Lithium iron phosphate (LiFePO4) as an effective activator for degradation of organic dyes in water in the presence of persulfate
Authors: Lin Xue-ming , Ma Yong-wen , Wang Yan , Wan Jin-quan , Guan Ze-yu
Published: October 2015

LiFePO4 was synthesized and successfully applied for activation of persulfate to produce sulfate radicals for dye degradation.
Nanospheres from the self-assembly of an elastin-inspired triblock peptide
Authors: Scelsi A. , Bochicchio B. , Smith A. , Saiani A. , Pepe A.
Published: October 2015

The self-assembly of an elastin-inspired triblock peptide into nanospheres highlights the important role of conformational flexibility and π–π stacking.
Rapid oxidative hydrogen evolution from a family of square-planar nickel hydride complexes
Authors: Ramakrishnan Srinivasan , Chakraborty Sumit , Brennessel William W. , Chidsey Christopher E. D. , Jones William D.
Published: October 2015

One-electron oxidation in a family of square planar nickel hydride complexes leads to facile H2 evolution.
Drainage in a rising foam
Authors: Yazhgur Pavel , Rio Emmanuelle , Rouyer Florence , Pigeonneau Franck , Salonen Anniina
Published: October 2015

Foams are an integral part of many industrial processes and for many of these it is crucial to control the foam formation parameters. In our experiment we study rising foams and predict the liquid fraction profile for foams with different interfacial mobilities.
Crystal structure of Mycobacterium tuberculosis O6-methylguanine-DNA methyltransferase protein clusters assembled on to damaged DNA
Authors: Miggiano Riccardo , Perugino Giuseppe , Ciaramella Maria , Serpe Mario , Rejman Dominik , Páv Ondřej , Pohl Radek , Garavaglia Silvia , Lahiri Samarpita , Rizzi Menico , Rossi Franca
Published: October 2015

Mycobacterium tuberculosis O 6-methylguanine-DNA methyltransferase (MtOGT) contributes to protect the bacterial GC-rich genome against the pro-mutagenic potential of O6-methylated guanine in DNA. Several strains of M. tuberculosis found worldwide encode a point-mutated O6-methylguanine-DNA methyltransferase (OGT) variant (MtOGT-R37L), which displays an arginine-to-leucine substitution at position 37 of the poorly functionally characterized N-terminal domain of the protein. Although the impact of this mutation on the MtOGT activity has not yet been proved in vivo, we previously demonstrated that a recombinant MtOGT-R37L variant performs a suboptimal alkylated-DNA repair in vitro, suggesting a direct role for the Arg37-bearing region in catalysis. The crystal structure of MtOGT complexed with modified DNA solved in the present study reveals details of the protein–protein and protein–DNA interactions occurring during alkylated-DNA binding, and the protein capability also to host unmodified bases inside the active site, in a fully extrahelical conformation. Our data provide the first experimental picture at the atomic level of a possible mode of assembling three adjacent MtOGT monomers on the same monoalkylated dsDNA molecule, and disclose the conformational flexibility of discrete regions of MtOGT, including the Arg37-bearing random coil. This peculiar structural plasticity of MtOGT could be instrumental to proper protein clustering at damaged DNA sites, as well as to protein–DNA complexes disassembling on repair.
Photonic‐assisted microwave amplification using four‐wave mixing
Authors: Cerqueira Sodré Arismar , Cañas‐Estrada Natalia , Noque Dionisio F. , Borges Ramon M. , Melo Suzanne A.S. , González Neil G. , Oliveira Julio C.R.F.
Published: October 2015

This work reports the development of a high‐gain and wideband photonic‐assisted amplified radio over fibre (RoF) system based on the non‐linear effect four‐wave mixing (FWM). The microwave gain is defined as the difference between the electrical power photodetected using a FWM product and that from the conventional RoF system at the same optical power level. Numerical simulations and experimental results prove that microwave gain strongly depends on the system parameters, such as wavelength separation between pump sources, state of polarisation, radio frequency modulation frequency and DC bias voltage of optical modulator. Microwave amplification from 4 to 19 GHz, electrical signal‐to‐noise ratio higher than 51 dB and gain up to 26 dB at 17 GHz are demonstrated. Moreover, an optical‐wireless network based on the photonic‐assisted microwave application is proposed, with the purpose of illustrating its applicability.
High‐efficiency low‐noise pulse‐width modulation DC–DC buck converter based on multi‐partition switching for mobile system‐on‐a‐chip applications
Authors: An Tai‐Ji , Ahn Gil‐Cho , Lee Seung‐Hoon
Published: October 2015

This study presents a high‐efficiency low‐noise pulse‐width modulation (PWM) DC–DC buck converter based on multi‐partition switching for mobile system‐on‐a‐chip applications. A multi‐partition switching technique is employed for the control of large current driving switches to minimise the switching noise. In addition, a PWM control with a switching frequency of 2 MHz is applied for the driving of output stage with a heavy load to optimise the power efficiency. The prototype DC–DC buck converter with an active die area of 0.28 mm2 was implemented using a 0.18 µm bipolar‐CMOS–DMOS (BCD) process. The peak power efficiency is 93%, while supplying an output current of 200 mA and an output voltage of 1.8 V.
Comparative study of reactive power control methods for photovoltaic inverters in low‐voltage grids
Authors: Momeneh Arash , Castilla Miguel , Miret Jaume , Martí Pau , Velasco Manel
Published: October 2015

The increasing installation of photovoltaic panels in low‐voltage grids causes an over voltage problem, especially during high production and low consumption periods. Generally the over voltage problem is overcome by implementing reactive power control methods. The advances in networked control systems theory and practice create new scenarios where reactive power control methods can offer additional features and benefits. To explore these new capabilities, this study presents two new reactive power control methods that exploit the networked approach. These two methods are evaluated in a comparative reference framework that also includes the base‐line case where no reactive control method is applied, the conventional droop method approach, and a solution based on a near‐optimal location of a high power STATCOM derived from one of the new proposed networked methods. The main merit factors used to compare the control methods are the maximum voltage across the distribution grid, the power factor in the point of common coupling, and the total power losses and economic cost of the installation. With these merit factors, the advantages and limitations of the new and existing control methods are revealed and discussed. A useful discussion for selecting the best control solution is also reported.
Taguchi method‐based probabilistic load flow studies considering uncertain renewables and loads
Authors: Hong Ying‐Yi , Lin Faa‐Jeng , Yu Ti‐Hsuan
Published: October 2015

Load flow studies are crucial in investigations of operation and planning problems in the power systems. Traditional methods for determining load flow are based on deterministic approaches. However, the parameters of a power system (such as load and renewable power generation) may be uncertain. An exact probabilistic load flow (PLF) study requires a long CPU time due to many convolution computations involving probability density functions. This paper proposes a novel PLF method that is based on Taguchi's orthogonal arrays. The proposed method utilises a few deterministic load flow solutions that are obtained using Taguchi's method to estimate the means and standard deviations of bus voltages, phase angles, line flows, and other metrics. A load flow calculation corresponds to an experiment in Taguchi's method. An optimal experiment is also specified by considering the largest deviation from the nominal load flow solution. A 25‐bus standalone power system and a modified Institute of Electrical and Electronics Engineers (IEEE) 118‐bus system are tested. The simulation results show that the proposed method not only requires fewer deterministic load flow solutions to perform PLF analysis than the traditional point‐estimate method but also yields accurate means and standard deviations of bus voltages and line flows.
Kinetic model of metabolic network for xiamenmycin biosynthetic optimisation
Authors: Xu Min‐juan , Chen Yong‐cong , Xu Jun , Ao Ping , Zhu Xiao‐mei
Published: October 2015

Xiamenmycins, a series of prenylated benzopyran compounds with anti‐fibrotic bioactivities, were isolated from a mangrove‐derived Streptomyces xiamenensis. To fulfil the requirements of pharmaceutical investigations, a high production of xiamenmycin is needed. In this study,, the authors present a kinetic metabolic model to evaluate fluxes in an engineered Streptomyces lividans with xiamenmycin‐oriented genetic modification based on generic enzymatic rate equations and stability constraints. Lyapunov function was used for a viability optimisation. From their kinetic model, the flux distributions for the engineered S. lividans fed on glucose and glycerol as carbon sources were calculated. They found that if the bacterium can utilise glucose simultaneously with glycerol, xiamenmycin production can be enhanced by 40% theoretically, while maintaining the same growth rate. Glycerol may increase the flux for phosphoenolpyruvate synthesis without interfering citric acid cycle. They therefore believe this study demonstrates a possible new direction for bioengineering of S. lividans.
Excess entropy and crystallization in Stillinger-Weber and Lennard-Jones fluids
Authors: Dhabal Debdas , Nguyen Andrew Huy , Singh Murari , Khatua Prabir , Molinero Valeria , Bandyopadhyay Sanjoy , Chakravarty Charusita
Published: October 2015

Molecular dynamics simulations are used to contrast the supercooling and crystallization behaviour of monatomic liquids that exemplify the transition from simple to anomalous, tetrahedral liquids. As examples of simple fluids, we use the Lennard-Jones (LJ) liquid and a pair-dominated Stillinger-Weber liquid (SW16). As examples of tetrahedral, water-like fluids, we use the Stillinger-Weber model with variable tetrahedrality parameterized for germanium (SW20), silicon (SW21), and water (SW23.15 or mW model). The thermodynamic response functions show clear qualitative differences between simple and water-like liquids. For simple liquids, the compressibility and the heat capacity remain small on isobaric cooling. The tetrahedral liquids in contrast show a very sharp rise in these two response functions as the lower limit of liquid-phase stability is reached. While the thermal expansivity decreases with temperature but never crosses zero in simple liquids, in all three tetrahedral liquids at the studied pressure, there is a temperature of maximum density below which thermal expansivity is negative. In contrast to the thermodynamic response functions, the excess entropy on isobaric cooling does not show qualitatively different features for simple and water-like liquids; however, the slope and curvature of the entropy-temperature plots reflect the heat capacity trends. Two trajectory-based computational estimation methods for the entropy and the heat capacity are compared for possible structural insights into supercooling, with the entropy obtained from thermodynamic integration. The two-phase thermodynamic estimator for the excess entropy proves to be fairly accurate in comparison to the excess entropy values obtained by thermodynamic integration, for all five Lennard-Jones and Stillinger-Weber liquids. The entropy estimator based on the multiparticle correlation expansion that accounts for both pair and triplet correlations, denoted by Strip, is also studied. Strip is a good entropy estimator for liquids where pair and triplet correlations are important such as Ge and Si, but loses accuracy for purely pair-dominated liquids, like LJ fluid, or near the crystallization temperature (Tthr). Since local tetrahedral order is compatible with both liquid and crystalline states, the reorganisation of tetrahedral liquids is accompanied by a clear rise in the pair, triplet, and thermodynamic contributions to the heat capacity, resulting in the heat capacity anomaly. In contrast, the pair-dominated liquids show increasing dominance of triplet correlations on approaching crystallization but no sharp rise in either the pair or thermodynamic heat capacities.
Resolving molecular vibronic structure using high-sensitivity two-dimensional electronic spectroscopy
Authors: Bizimana Laurie A. , Brazard Johanna , Carbery William P. , Gellen Tobias , Turner Daniel B.
Published: October 2015

Coherent multidimensional optical spectroscopy is an emerging technique for resolving structure and ultrafast dynamics of molecules, proteins, semiconductors, and other materials. A current challenge is the quality of kinetics that are examined as a function of waiting time. Inspired by noise-suppression methods of transient absorption, here we incorporate shot-by-shot acquisitions and balanced detection into coherent multidimensional optical spectroscopy. We demonstrate that implementing noise-suppression methods in two-dimensional electronic spectroscopy not only improves the quality of features in individual spectra but also increases the sensitivity to ultrafast time-dependent changes in the spectral features. Measurements on cresyl violet perchlorate are consistent with the vibronic pattern predicted by theoretical models of a highly displaced harmonic oscillator. The noise-suppression methods should benefit research into coherent electronic dynamics, and they can be adapted to multidimensional spectroscopies across the infrared and ultraviolet frequency ranges.
Spin-torque switching of a nano-magnet using giant spin hall effect
Authors: Penumatcha Ashish V. , Das Suprem R. , Chen Zhihong , Appenzeller Joerg
Published: October 2015

The Giant Spin Hall Effect(GSHE) in metals with high spin-orbit coupling is an efficient way to convert charge currents to spin currents, making it well-suited for writing information into magnets in non-volatile magnetic memory as well as spin-logic devices. We demonstrate the switching of an in-plane CoFeB magnet using a combination of GSHE and an external magnetic field. The magnetic field dependence of the critical current is used to estimate the spin hall angle with the help of a thermal activation model for spin-transfer torque switching of a nanomagnet.
Ignoring the science in failing to conserve a faunal icon – major political, policy and management problems in preventing the extinction of Leadbeater’s possum
Authors: Lindenmayer David B. , Blair David , McBurney Lachlan , Banks Sam C.
Published: October 2015

Leadbeater’s possum (Gymnobelideus leadbeateri) is an arboreal marsupial that occurs primarily in the montane ash forests of the Central Highlands of Victoria. Leadbeater’s possum is among the best studied endangered species globally. Despite extensive monitoring and research, the ongoing population trajectory of the species has resulted in its recent upgrading from Endangered to Critically Endangered. One of the key processes threatening the species is the widespread use of clearfell logging, which significantly degrades the habitat of the species and results in long-term habitat loss, fragmented populations, and an elevated risk of high-severity crown-scorching fires. A general principle underpinning conservation biology is to remove key threatening processes to enhance the conservation of species. The cessation of clearfell logging and a major expansion of the reserve system are urgently needed to limit the risk of extinction of Leadbeater’s possum. Current government policies and practices that continue to result in clearfelling of montane ash forests run counter to the large body of science indicating what is needed to conserve Leadbeater’s possum. A large ecological reserve is urgently required to maximise the chances that the species will persist in the wild.
The haematology of six species of native catfish from northern Australia
Authors: Kelly E. , Gibson-Kueh S.
Published: October 2015

Haematology has the potential to be a valuable tool in determining the health status of wild fish populations and wider ecosystem health. However, limited haematological data are available for wild Australian fish species, and the interpretation and nomenclature of leukocytes is variable and inconsistent in fish. The morphology and cytochemical reactions of erythrocytes, thrombocytes and leukocytes of 189 wild eel-tailed catfish (Tandanus tandanus), Wet Tropics tandan (Tandanus tropicanus), Hyrtyl’s tandan (Neosilurus hyrtlii), black catfish (Neosilurus ater), lesser salmon catfish (Neoarius graeffei), and silver cobbler (Neoarius midgleyi) are described. Erythrocytes, thrombocytes, lymphocytes, monocytes and heterophils in all six species are morphologically similar to those reported in other Siluriformes. Basophils and eosinophils are rarely reported in fish; however basophils were observed in peripheral blood smears of T. tropicanus and N. ater, and eosinophils were observed in N. graeffei. Periodic acid Schiff positive granular leukocytes were observed in N. graeffei, N. midgleyi, N. ater and T. tandanus. This is the first report on the leukocyte morphology and cytochemistry of any native Australian catfish species, and provides useful baseline data for future assessments of fish health and ecosystem integrity in Australia.
RNA sensing by conventional dendritic cells is central to the development of lupus nephritis
Authors: Celhar Teja , Hopkins Richard , Thornhill Susannah I. , De Magalhaes Raquel , Hwang Sun-Hee , Lee Hui-Yin , Yasuga Hiroko , Jones Leigh A. , Casco Jose , Lee Bernett , Thamboo Thomas P. , Zhou Xin J. , Poidinger Michael , Connolly John E. , Wakeland Edward K. , Fairhurst Anna-Marie
Published: October 2015

Significance

Systemic lupus erythematosus is a complex autoimmune disease where genetic and environmental factors play equally important roles. Recent research has identified that upregulation of the innate immune Toll-like receptor 7 (TLR7) is fundamental for the development of severe disease. In ourSle1Tg7 model system, we show that increased expression of TLR7 in dendritic cells (DCs) is important for the development of kidney disease. Furthermore, we identify conventional CD11b+DCs infiltrating the glomeruli of diseased mice. In a resting state, human myeloid DCs express negligible levels of TLR7. However, exposure to multiple stimuli results in a dramatic increase in expression. Together, these findings suggest a role for myeloid DC-TLR7 in clinical disease and that TLR7 expression in this cellular compartment may represent a novel target for therapeutic investigation.
Fly LMBR1/LIMR-type protein Lilipod promotes germ-line stem cell self-renewal by enhancing BMP signaling
Authors: Dolezal Darin , Liu Zhiyan , Zhou Qingxiang , Pignoni Francesca
Published: October 2015

Significance

Adult stem cells are maintained in an undifferentiated state in response to factors provided by their surrounding niche microenvironment. The
Drosophila
limb development membrane protein-1 (LMBR1)/lipocalin-interacting membrane receptor (LIMR) type transmembrane protein Lilipod (Lili) is required in ovarian germ-line stem cells (GSC) for their self-renewal. In the fly ovary, niche-secreted bone morphogenetic protein (BMP) ligands activate signaling in the GSC to suppress transcription of the differentiation factor Bam. Lili is required for this suppression and functions as a modulator of BMP signal transduction in this and other contexts. LMBR1/LIMR type transmembrane proteins are conserved throughout the Metazoa, and this study provides the first example to our knowledge of physiological function in a model organism.
Producing desired ice faces
Authors: Shultz Mary Jane , Brumberg Alexandra , Bisson Patrick J. , Shultz Ryan
Published: October 2015

Significance

The molecular-level structure of ice––bonding patterns, binding sites, and molecular mobility––is difficult to probe experimentally due to challenges preparing faces of neat ice. One approach is to grow ice on a substrate. However, ice is held together by hydrogen bonds; a substrate perturbs the connections and radically alters the surface properties. This work shows how to quantitatively specify orientation of the ice lattice with respect to a surface. More importantly, based on recent success growing large single crystals, it shows how to prepare any desired face from the initial crystal surface orientation. A general procedure for preparing any arbitrary face is described. The procedure is used to prepare all three major faces from various initial orientations.
Growing the terrestrial planets from the gradual accumulation of submeter-sized objects
Authors: Levison Harold F. , Kretke Katherine A. , Walsh Kevin J. , Bottke William F.
Published: October 2015

Significance

The fact that Mars is so much smaller than both Earth and Venus has been a long-standing puzzle of terrestrial planet formation. Here we show that a new mode of planet formation known as “Viscous Stirred Pebble Accretion,” which has recently been shown to produce the giant planets, also naturally explains the small size of Mars and the low mass of the asteroid belt. Thus there is a unified model that can be used to explain all of the basic properties of our solar system.
A priori calculations of the free energy of formation from solution of polymorphic self-assembled monolayers
Authors: Reimers Jeffrey R. , Panduwinata Dwi , Visser Johan , Chin Yiing , Tang Chunguang , Goerigk Lars , Ford Michael J. , Sintic Maxine , Sum Tze-Jing , Coenen Michiel J. J. , Hendriksen Bas L. M. , Elemans Johannes A. A. W. , Hush Noel S. , Crossley Maxwell J.
Published: October 2015

Significance

First-principles free energy calculations, characterizing polymorphism of self-assembled monolayers (SAMs) of porphyrin molecules formed from solution onto graphite, are performed using efficient methods previously applied only to small-molecule reactivity. SAM structures are typically optimized in the absence of solvent using density functional theory embodying explicit dispersion corrections. Added then are dispersion-dominated implicit solvation energies and SAM formation entropies derived from both molecular and phonon vibration frequencies. Scanning tunneling microscopy (STM) images are measured, and polymorph formation free energies are approximated. Close parallels between experiment and theory support the hypothesis that the first seconds of SAM formation are under thermodynamic control, despite formed SAMs being kinetically trapped. Polymorphism is associated with large opposing changes to entropy and substrate−molecule and solvent−molecule interaction energies.
Robustness of sensory-evoked excitation is increased by inhibitory inputs to distal apical tuft dendrites
Authors: Egger Robert , Schmitt Arno C. , Wallace Damian J. , Sakmann Bert , Oberlaender Marcel , Kerr Jason N. D.
Published: October 2015

Significance

Even the simplest sensory stimulus activates millions of synapses across the cortex. How neurons integrate these highly specialized, but noisy synaptic input patterns to generate robust electrophysiological responses—that ultimately translate into behavior—remains elusive. Here, we provide first insight into a mechanism that may underlie the general phenomenon, observed across sensory modalities and species, that stimulation decreases variability in neuronal activity. Specifically, we show that during sensory stimulation, highly specialized inhibitory neurons provide synaptic input to distal dendrites of excitatory neurons, which reduces variability but not the mean amplitude of the response. Distal dendritic shunting may thus represent a general principle of cortex organization to ensure that noisy synaptic input patterns translate into robust sensory-evoked neuronal activity.
Learning intentions and success criteria: learners' and teachers' views
Authors: Crichton Hazel , McDaid Ann
Published: October 2015

It is generally accepted that Assessment for Learning (AfL) strategies are effective in teaching and learning. Approaches within this framework include the use of formative feedback, self and peer assessment and setting and discussion of learning intentions (LIs) and success criteria (SC). There has been a great deal of research into AfL strategies, but perhaps less into the way that the use of LIs and SC are actually perceived by teachers and their pupils. The purpose of the research described in this paper was to investigate teachers’ and pupils’ perceptions of AfL strategies, focusing specifically on LIs and SC within lessons. Findings showed that while both cohorts agreed on the usefulness of LIs and SC, in practice they were rarely discussed in class. Teachers displayed a variety of understandings regarding their purpose, and some learners, while appreciating their value for revision purposes, also expressed frustration at the tokenistic way in which they were implemented. The results of this study could be helpful in informing the wider education community about how LIs and SC are viewed by teachers and learners with a view to ensure understandings are consistent with research and policy through focused professional development courses.
Sarcasm and emoticons: Comprehension and emotional impact
Authors: Filik Ruth , Țurcan Alexandra , Thompson Dominic , Harvey Nicole , Davies Harriet , Turner Amelia
Published: October 2015

Most theorists agree that sarcasm serves some communicative function that would not be achieved by speaking directly, such as eliciting a particular emotional response in the recipient. One debate concerns whether this kind of language serves to enhance or mute the positive or negative nature of a message. The role of textual devices commonly used to accompany written sarcastic remarks is also unclear. The current research uses a rating task to investigate the influence of textual devices (emoticons and punctuation marks) on the comprehension of, and emotional responses to, sarcastic versus literal criticism and praise, for both unambiguous (Experiment 1) and ambiguous (Experiment 2) materials. Results showed that sarcastic criticism was rated as less negative than literal criticism, and sarcastic praise was rated as less positive than literal praise, suggesting that sarcasm serves to mute the positive or negative nature of the message. In terms of textual devices, results showed that emoticons had a larger influence on both comprehension and emotional impact than punctuation marks.