bluuebunny/crossref_metadata_2025 huggingface dataset:
New insights into the causes of human illness due to consumption of azaspiracid contaminated shellfish
Authors: Chevallier O. P. , Graham S. F. , Alonso E. , Duffy C. , Silke J. , Campbell K. , Botana L. M. , Elliott C. T.
Published: April 2015

Azaspiracid (AZA) poisoning was unknown until 1995 when shellfish harvested in Ireland caused illness manifesting by vomiting and diarrhoea. Further in vivo/vitro studies showed neurotoxicity linked with AZA exposure. However, the biological target of the toxin which will help explain such potent neurological activity is still unknown. A region of Irish coastline was selected and shellfish were sampled and tested for AZA using mass spectrometry. An outbreak was identified in 2010 and samples collected before and after the contamination episode were compared for their metabolite profile using high resolution mass spectrometry. Twenty eight ions were identified at higher concentration in the contaminated samples. Stringent bioinformatic analysis revealed putative identifications for seven compounds including, glutarylcarnitine, a glutaric acid metabolite. Glutaric acid, the parent compound linked with human neurological manifestations was subjected to toxicological investigations but was found to have no specific effect on the sodium channel (as was the case with AZA). However in combination, glutaric acid (1mM) and azaspiracid (50nM) inhibited the activity of the sodium channel by over 50%. Glutaric acid was subsequently detected in all shellfish employed in the study. For the first time a viable mechanism for how AZA manifests itself as a toxin is presented.
Self-organized alternating chimera states in oscillatory media
Authors: Haugland Sindre W. , Schmidt Lennart , Krischer Katharina
Published: April 2015

Oscillatory media can exhibit the coexistence of synchronized and desynchronized regions, so-called chimera states, for uniform parameters and symmetrical coupling. In a phase-balanced chimera state, where the totals of synchronized and desynchronized regions, respectively, are of the same size, the symmetry of the system predicts that interchanging both phases still gives a solution to the underlying equations. We observe this kind of interchange as a self-emerging phenomenon in an oscillatory medium with nonlinear global coupling. An interplay between local and global couplings renders the formation of these alternating chimeras possible.
Optical Control of Fluorescence through Plasmonic Eigenmode Extinction
Authors: Xu Xiaoying , Lin Shih-Che , Li Quanshui , Zhang Zhili , Ivanov Ilia N. , Li Yuan , Wang Wenbin , Gu Baohua , Zhang Zhenyu , Hsueh Chun-Hway , Snijders Paul C. , Seal Katyayani
Published: April 2015

We introduce the concept of optical control of the fluorescence yield of CdSe quantum dots through plasmon-induced structural changes in random semicontinuous nanostructured gold films. We demonstrate that the wavelength- and polarization dependent coupling between quantum dots and the semicontinuous films, and thus the fluorescent emission spectrum, can be controlled and significantly increased through the optical extinction of a selective band of eigenmodes in the films. This optical method of effecting controlled changes in the metal nanostructure allows for versatile functionality in a single sample and opens a pathway to in situ control over the fluorescence spectrum.
Temperature effects on nanostructure and mechanical properties of single-nanoparticle thick membranes
Authors: Salerno K. Michael , Grest Gary S.
Published: April 2015

The properties of mechanically stable single-nanoparticle (NP)-thick membranes have largely been studied at room temperature. How these membranes soften as nanoparticle ligands disorder with increasing temperature is unknown. Molecular dynamics simulations are used to probe the temperature dependence of the mechanical and nanostructural properties of nanoparticle membranes made of 6 nm diameter Au nanoparticles coated with dodecanethiol ligands and terminated with either methyl (CH3) or carboxyl (COOH) terminal groups. For methyl-terminated ligands, interactions along the alkane chain provide mechanical stiffness, with a Young's modulus of 1.7 GPa at 300 K. For carboxyl-terminated chains, end-group interactions are significant, producing stiffer membranes at all temperatures, with a Young's modulus of 3.8 GPa at 300 K. For both end-group types, membrane stiffness is reduced to zero at about 400 K. Ligand structure and mechanical properties of membranes at 300 K that have been annealed at 400 K are comparable to samples that do not undergo thermal annealing.
Ultrafast high-resolution magic-angle-spinning NMR spectroscopy
Authors: André Marion , Piotto Martial , Caldarelli Stefano , Dumez Jean-Nicolas
Published: April 2015

The acquisition of ultrafast high-resolution magic-angle spinning (HR-MAS) NMR spectra of semi-solid samples is demonstrated.
A facile one-pot synthesis of colloidal stable, monodisperse, highly PEGylated CuS@mSiO2 nanocomposites for the combination of photothermal therapy and chemotherapy
Authors: Lu Feng , Wang Jinfeng , Yang Lin , Zhu Jun-Jie
Published: April 2015

A facile one-pot approach was developed for the synthesis of colloidal stable, monodisperse, highly PEGylated mesoporous silica coated CuS nanocomposites.
A facile strategy to synthesize three-dimensional Pd@Pt core–shell nanoflowers supported on graphene nanosheets as enhanced nanoelectrocatalysts for methanol oxidation
Authors: Chen Yi , Yang Jia , Yang Ying , Peng Zhiyao , Li Jinhua , Mei Tao , Wang Jianying , Hao Ming , Chen Yalin , Xiong Weilai , Zhang Liu , Wang Xianbao
Published: April 2015

A water-based surfactant-free synthesis of three-dimensional porous Pd@Pt core–shell nanoflowers on graphene with substantially enhanced electrocatalytic activity was reported.
VCD spectroscopy as an excellent probe of chiral metal complexes containing a carbon monoxide vibrational chromophore
Authors: Fusè Marco , Mazzeo Giuseppe , Longhi Giovanna , Abbate Sergio , Zerla Daniele , Rimoldi Isabella , Contini Alessandro , Cesarotti Edoardo
Published: April 2015

η5-Menthyl-C5H4Ru(ii) carbonyl complexes show VCD of CO; the stretching is very sensitive and diagnostic to the (R)Ru/(S)Rumetal chirality.
Utilization of a Meldrum's acid towards functionalized fluoropolymers possessing dual reactivity for thermal crosslinking and post-polymerization modification
Authors: Wu Jingbo , Iacono Scott T. , McCandless Gregory T. , Smith Dennis W. , Novak Bruce M.
Published: April 2015

New thermally cross-linkable and/or post-functionalizable perfluorocyclobutyl (PFCB) polymers containing Meldrum's acid from trifluorovinyl ether monomers.
On the handedness of helical aggregates of C3 tricarboxamides: a multichiroptical characterization
Authors: Nieto-Ortega Belén , García Fátima , Longhi Giovanna , Castiglioni Ettore , Calbo Joaquín , Abbate Sergio , López Navarrete Juan T. , Ramírez Francisco J. , Ortí Enrique , Sánchez Luis , Casado Juan
Published: April 2015

A multichiroptical characterization of the supramolecular polymers formed by C3 tricarboxamides is performed using ECD, VCD, CPL and theoretical calculations.
Sequestering uranium from UO2(CO3)34−in seawater with amine ligands: density functional theory calculations
Authors: Guo Xiaojing , Huang Liangliang , Li Cheng , Hu Jiangtao , Wu Guozhong , Huai Ping
Published: April 2015

The stabilities of complexes of uranyls with primary amines and CO32−groups decrease with increasing chain length of the amine.
Electronic structure and conformational flexibility of d-cycloserine
Authors: Filippi Antonello , Fraschetti Caterina , Grandinetti Felice , Speranza Maurizio , Ponzi Aurora , Decleva Piero , Stranges Stefano
Published: April 2015

The conformational flexibility effect on the valence and core electronic structures of d-cycloserine.
Characterizing gaseous peptide structure with action-EET and simulated annealing
Authors: Hendricks Nathan G. , Julian Ryan R.
Published: April 2015

Distance-sensitive energy transfer and molecular dynamics are used to generate experimentally corroborated structures for peptides in the gas phase.
Excited state interactions between the chiral Au38L24 cluster and covalently attached porphyrin
Authors: Varnholt Birte , Letrun Romain , Bergkamp Jesse J. , Fu Yongchun , Yushchenko Oleksandr , Decurtins Silvio , Vauthey Eric , Liu Shi-Xia , Bürgi Thomas
Published: April 2015

Excited state interactions between the Au38L24 cluster and the covalently attached porphyrin molecules lead to energy transfer upon excitation.
A new approach to elucidating repair reactions of resveratrol
Authors: Kerzig Christoph , Henkel Selgar , Goez Martin
Published: April 2015

Near-UV photoionization is a direct and selective access to the phenoxy radical ResO˙ of the famous antioxidant resveratrol. Coupled with a new direct detection, it permits a facile exploration of ResO˙ repair by biologically important co-antioxidants such as ascorbate (HAsc−), especially in organized phases, so might significantly contribute to the understanding of complex radical scavenging cascades.
Sulfonic acid-functionalized periodic mesoporous organosilicas in esterification and selective acylation reactions
Authors: Karimi Babak , Mirzaei Hamid M. , Mobaraki Akbar , Vali Hojatollah
Published: April 2015

A simple adjustment of surface physicochemical properties of the solid acid catalysts would provide selective formation of the desired products in esterification reactions.
Bicontinuous microemulsions for high yield, wet synthesis of ultrafine nanoparticles: a general approach
Authors: Latsuzbaia Roman , Negro Emanuela , Koper Ger
Published: April 2015

The design of a synthesis strategy for metal nanoparticles by templating dense microemulsions is proposed. Particle size is controlled by surfactant size rather than by microemulsion composition. The strategy was demonstrated with various systems with different surfactant: cationic, anionic and non-ionic and of different sizes. Formulations were determined using the microemulsion phase diagrams. Synthesis was demonstrated for platinum nanoparticles with some examples for gold. The nanoparticles were subsequently extracted from the microemulsion by absorption onto a carbon support, after which the surfactant was recycled.
Perspectives on the replacement of harmful organic solvents in analytical methodologies: a framework toward the implementation of a generation of eco-friendly alternatives
Authors: Pena-Pereira Francisco , Kloskowski Adam , Namieśnik Jacek
Published: April 2015

This perspective addresses the replacement of harmful organic solvents by a novel generation of promising alternatives using sustainable analytical methodologies.
Enhanced catalytic activity of nanoporous Cu3(BTC)2 metal–organic framework via immobilization of oxodiperoxo molybdenum complex
Authors: Abednatanzi Sara , Abbasi Alireza , Masteri-Farahani Majid
Published: April 2015

A new bimetallic heterogeneous epoxidation catalyst was prepared through chemical modification of Cu3(BTC)2 metal–organic framework.
A redox-responsive mesoporous silica nanoparticle capped with amphiphilic peptides by self-assembly for cancer targeting drug delivery
Authors: Xiao Dong , Jia Hui-Zhen , Ma Ning , Zhuo Ren-Xi , Zhang Xian-Zheng
Published: April 2015

A novel redox-responsive mesoporous silica nanoparticle (RRMSN/DOX) capped with amphiphilic peptides by self-assembly was demonstrated for targeting drug delivery in cancer cells.
Synthesis and properties of unsymmetrical azatrioxa[8]circulenes
Authors: Plesner Malene , Hensel Thomas , Nielsen Bjarne E. , Kamounah Fadhil S. , Brock-Nannestad Theis , Nielsen Christian B. , Tortzen Christian G. , Hammerich Ole , Pittelkow Michael
Published: April 2015

Synthesis and properties are reported for a series of unsymmetrical antiaromatic azatrioxa[8]circulenes.
Facile synthesis of acridines via Pd(0)-diphosphine complex-catalyzed tandem coupling/cyclization protocol
Authors: Wang Ting-Jun , Chen Wen-Wen , Li Yi , Xu Ming-Hua
Published: April 2015

A facile and efficient approach for the synthesis of a variety of acridines via the tandem coupling/cyclization of substituted 2-bromobenzaldehydes and anilines is described.
Entropically-driven ring-opening metathesis polymerization (ED-ROMP) of macrocyclic olefins prepared from deoxycholic acid to give functionalized polymers
Authors: Hodge Philip , Chakiri Abdel
Published: April 2015

The macrocycles shown were prepared, then polymerized and copolymerized by ROMP. This gave polymers with free OH or free CO2R groups. Treatment of the polymers having R =t-Bu with trifluoroacetic acid gave polymers with free CO2H groups.
Coupling a novel spiro-rhodamine B lactam derivative to Fe3O4 nanoparticles for visual detection of free copper ions with high sensitivity and specificity
Authors: Zhang Hongyan , Zeng Xiaoxue , Chen Danlong , Guo Ying , Jiang Wenjing , Xu Liangjun , Fu FengFu
Published: April 2015

A novel spiro-rhodamine B lactam derivative, which can be coupled to Fe3O4 NPs and act as a Cu2+-selective visual sensor is reported. It can be used to directly detect as little as 50 nM of Cu2+ in river or tap water by only naked-eye observation.
Synthesis and catalytic application of glycodendrimers decorated with gold nanoparticles – reduction of 4-nitrophenol
Authors: Kannan Ayyavoo , Rajakumar Perumal
Published: April 2015

Au–DSNPs and Au–DENPs with an average diameter of 7.2 and 4.0 nm have been synthesized and proved to be good catalysts for the reduction of 4-nitrophenol.
Highly selective CO2 adsorption performance of carbazole based microporous polymers
Authors: Saleh Muhammad , Kim Kwang S.
Published: April 2015

Non-coplanar shaped carbazole based monomers were used to synthesize microporous polycarbazole materials utilizing an inexpensive FeCl3 catalyzed reaction.
Deploying clinical grade magnetic nanoparticles with magnetic fields to magnetolabel neural stem cells in adherent versus suspension cultures
Authors: Weinberg D. , Adams C. F. , Chari D. M.
Published: April 2015

This is the first demonstration that oscillating magnetic fields safely promote the uptake of a clinical-grade magnetic nanoparticle (Lumirem/Ferumoxsil) into neural stem cells for non-invasive cell tracking capabilities.
Enantioselective synthesis of bicyclo[3.n.1]alkanes by chiral phosphoric acid-catalyzed desymmetrizing Michael cyclizations
Authors: Burns Alan R. , Madec Amaël G. E. , Low Darryl W. , Roy Iain D. , Lam Hon Wai
Published: April 2015

2,2-Disubstituted cyclic 1,3-diketones containing a tethered electron-deficient alkene undergo chiral phosphoric acid-catalyzed desymmetrizing Michael cyclizations to give bridged bicyclic products in high enantioselectivities.
A hybrid physical–chemical deposition process at ultra-low temperatures for high-performance perovskite solar cells
Authors: Peng Yanke , Jing Gaoshan , Cui Tianhong
Published: April 2015

The quality of a perovskite film will directly determine the performance and stability of the corresponding perovskite solar cell.
A novel mussel-inspired strategy toward superhydrophobic surfaces for self-driven crude oil spill cleanup
Authors: Wang Zhenxing , Xu Yanchao , Liu Yuyan , Shao Lu
Published: April 2015

A superhydrophobic fabric was first fabricated by a novel mussel-inspired strategy with the aid of folic acid and a low concentration of dopamine without any additional nanoparticle incorporation. A mini boat of this fabric can automatically recycle oil spills while floating freely on water.
Critical role of evolutionarily conserved glycosylation at Asn211 in the intracellular trafficking and activity of sialyltransferase ST3Gal-II
Authors: Ruggiero Fernando M. , Vilcaes Aldo A. , Iglesias-Bartolomé Ramiro , Daniotti José L.
Published: April 2015

ST3Gal-II, a type II transmembrane protein, is the main mammalian sialyltransferase responsible for GD1a and GT1b ganglioside biosynthesis in brain. It contains two putative N-glycosylation sites (Asn92 and Asn211). Whereas Asn92 is only conserved in mammalian species, Asn211 is highly conserved in mammals, birds and fish. The present study explores the occupancy and relevance for intracellular trafficking and enzyme activity of these potential N-glycosylations in human ST3Gal-II. We found that ST3Gal-II distributes along the Golgi complex, mainly in proximal compartments. By pharmacological, biochemical and site-directed mutagenesis, we observed that ST3Gal-II is mostly N-glycosylated at Asn211 and that this co-translational modification is critical for its exit from the endoplasmic reticulum and proper Golgi localization. The individual N-glycosylation sites had different effects on ST3Gal-II enzymatic activity. Whereas the N-glycan at position Asn211 seems to negatively influence the activity of the enzyme using both glycolipid and glycoprotein as acceptor substrates, the single N-glycan mutant at Asn92 had only a moderate effect. Lastly, we demonstrated that the N-terminal ST3Gal-II domain containing the cytosolic, transmembrane and stem region (amino acids 1–51) is able to drive a protein reporter out of the endoplasmic reticulum and to retain it in the Golgi complex. This suggests that the C-terminal domain of ST3Gal-II depends on N-glycosylation to attain an optimum conformation for proper exit from the endoplasmic reticulum, but it does not represent an absolute requirement for Golgi complex retention of the enzyme.
Interaction of chromatin with a histone H1 containing swapped N- and C-terminal domains
Authors: Hutchinson Jordana B. , Cheema Manjinder S. , Wang Jason , Missiaen Krystal , Finn Ron , Gonzalez Romero Rodrigo , Th’ng John P. H. , Hendzel Michael , Ausió Juan
Published: April 2015

Although the details of the structural involvement of histone H1 in the organization of the nucleosome are quite well understood, the sequential events involved in the recognition of its binding site are not as well known. We have used a recombinant human histone H1 (H1.1) in which the N- and C-terminal domains (NTD/CTD) have been swapped and we have reconstituted it on to a 208-bp nucleosome. We have shown that the swapped version of the protein is still able to bind to nucleosomes through its structurally folded wing helix domain (WHD); however, analytical ultracentrifuge analysis demonstrates its ability to properly fold the chromatin fibre is impaired. Furthermore, FRAP analysis shows that the highly dynamic binding association of histone H1 with the chromatin fibre is altered, with a severely decreased half time of residence. All of this suggests that proper binding of histone H1 to chromatin is determined by the simultaneous and synergistic binding of its WHD–CTD to the nucleosome.
Are reactive oxygen species still the basis for diabetic complications?
Authors: Marco Elyse Di , Jha Jay C. , Sharma Arpeeta , Wilkinson-Berka Jennifer L. , Jandeleit-Dahm Karin A. , de Haan Judy B.
Published: April 2015

Despite the wealth of pre-clinical support for a role for reactive oxygen and nitrogen species (ROS/RNS) in the aetiology of diabetic complications, enthusiasm for antioxidant therapeutic approaches has been dampened by less favourable outcomes in large clinical trials. This has necessitated a re-evaluation of pre-clinical evidence and a more rational approach to antioxidant therapy. The present review considers current evidence, from both pre-clinical and clinical studies, to address the benefits of antioxidant therapy. The main focus of the present review is on the effects of direct targeting of ROS-producing enzymes, the bolstering of antioxidant defences and mechanisms to improve nitric oxide availability. Current evidence suggests that a more nuanced approach to antioxidant therapy is more likely to yield positive reductions in end-organ injury, with considerations required for the types of ROS/RNS involved, the timing and dosage of antioxidant therapy, and the selective targeting of cell populations. This is likely to influence future strategies to lessen the burden of diabetic complications such as diabetes-associated atherosclerosis, diabetic nephropathy and diabetic retinopathy.
Development of a pulsed uniform supersonic gas expansion system based on an aerodynamic chopper for gas phase reaction kinetic studies at ultra-low temperatures
Authors: Jiménez E. , Ballesteros B. , Canosa A. , Townsend T. M. , Maigler F. J. , Napal V. , Rowe B. R. , Albaladejo J.
Published: April 2015

A detailed description of a new pulsed supersonic uniform gas expansion system is presented together with the experimental validation of the setup by applying the CRESU (French acronym for Cinétique de Réaction en Ecoulement Supersonique Uniforme or Reaction Kinetics in a Uniform Supersonic Flow) technique to the gas-phase reaction of OH radicals with 1-butene at ca. 23 K and 0.63 millibars of helium (carrier gas). The carrier gas flow, containing negligible mixing ratios of OH-precursor and 1-butene, is expanded from a high pressure reservoir (337 millibars) to a low pressure region (0.63 millibars) through a convergent-divergent nozzle (Laval type). The novelty of this experimental setup is that the uniform supersonic flow is pulsed by means of a Teflon-coated aerodynamic chopper provided with two symmetrical apertures. Under these operational conditions, the designed Laval nozzle achieves a temperature of (22.4 ± 1.4) K in the gas jet. The spatial characterization of the temperature and the total gas density within the pulsed uniform supersonic flow has also been performed by both aerodynamical and spectroscopic methods. The gas consumption with this technique is considerably reduced with respect to a continuous CRESU system. The kinetics of the OH+1-butene reaction was investigated by the pulsed laser photolysis/laser induced fluorescence technique. The rotation speed of the disk is temporally synchronized with the exit of the photolysis and the probe lasers. The rate coefficient (kOH) for the reaction under investigation was then obtained and compared with the only available data at this temperature.
Solid-liquid interfaces of ionic liquid solutions—Interfacial layering and bulk correlations
Authors: Mezger Markus , Roth Roland , Schröder Heiko , Reichert Peter , Pontoni Diego , Reichert Harald
Published: April 2015

The influence of the polar, aprotic solvent propylene carbonate on the interfacial structure of the ionic liquid (IL) 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate on sapphire was investigated by high-energy x-ray reflectivity. Experiments at solvent concentrations between 17 mol. % and 83 mol. % bridge the gap between diluted electrolytes described by the classical Gouy-Chapman theory and pure ionic liquids. Analysis of our experimental data revealed interfacial profiles comprised of alternating anion and cation enriched regions decaying gradually into the bulk liquid. With increasing solvent concentration, we observed a decrease in correlation length of the interfacial layering structure. At high ion concentrations, solvent molecules were found to accumulate laterally within the layers. By separating like-charged ions, they reduce their Coulomb repulsion. The results are compared with the bulk structure of IL/solvent blends probed by x-ray scattering and predictions from fundamental fluid theory.
Vapor-deposited non-crystalline phase vs ordinary glasses and supercooled liquids: Subtle thermodynamic and kinetic differences
Authors: Bhattacharya Deepanjan , Sadtchenko Vlad
Published: April 2015

Vapor deposition of molecules on a substrate often results in glassy materials of high kinetic stability and low enthalpy. The extraordinary properties of such glasses are attributed to high rates of surface diffusion during sample deposition, which makes it possible for constituents to find a configuration of much lower energy on a typical laboratory time scale. However, the exact nature of the resulting phase and the mechanism of its formation are not completely understood. Using fast scanning calorimetry technique, we show that out-of-equilibrium relaxation kinetics and possibly the enthalpy of vapor-deposited films of toluene and ethylbenzene, archetypical fragile glass formers, are distinct from those of ordinary supercooled phase even when the deposition takes place at temperatures above the ordinary glass softening transition temperatures. These observations along with the absolute enthalpy dependences on deposition temperatures support the conjecture that the vapor-deposition may result in formation of non-crystalline phase of unique structural, thermodynamic, and kinetic properties.
Stochastic rotation dynamics for nematic liquid crystals
Authors: Lee Kuang-Wu , Mazza Marco G.
Published: April 2015

We introduce a new mesoscopic model for nematic liquid crystals (LCs). We extend the particle-based stochastic rotation dynamics method, which reproduces the Navier-Stokes equation, to anisotropic fluids by including a simplified Ericksen-Leslie formulation of nematodynamics. We verify the applicability of this hybrid model by studying the equilibrium isotropic-nematic phase transition and nonequilibrium problems, such as the dynamics of topological defects and the rheology of sheared LCs. Our simulation results show that this hybrid model captures many essential aspects of LC physics at the mesoscopic scale, while preserving microscopic thermal fluctuations.
Local thermal resonance control of GaInP photonic crystal membrane cavities using ambient gas cooling
Authors: Sokolov Sergei , Lian Jin , Yüce Emre , Combrié Sylvain , Lehoucq Gaelle , De Rossi Alfredo , Mosk Allard P.
Published: April 2015

We perform spatially dependent tuning of a GaInP photonic crystal cavity using a continuous wave violet laser. Local tuning is obtained by laser heating of the photonic crystal membrane. The cavity resonance shift is measured for different pump positions and for two ambient gases: He and N2. We find that the width of the temperature profile induced in the membrane depends strongly on the thermal conductivity of the ambient gas. For He gas, a narrow spatial width of the temperature profile of 2.8 μm is predicted and verified in experiment.
Gold nanorods-silica Janus nanoparticles for theranostics
Authors: Wang Ying-Shuai , Shao Dan , Zhang Lu , Zhang Xu-Lin , Li Jing , Feng Jing , Xia Hong , Huo Qi-Sheng , Dong Wen-Fei , Sun Hong-Bo
Published: April 2015

A multi-functional gold nanorods-mesoporous silica Janus nanoparticles (NPs) were fabricated by a facile and mild strategy. These Janus NPs not only exhibit small shift of the local surface plasmon resonance wavelength but also have high potential for drug loading and low cytotoxicity. More importantly, the Janus nano-composites could efficiently deliver the imaging agents or drugs into liver cancer cells, at the same time the Janus NPs have good effect on photothermal, which indicate that the unique Janus NPs could be a promising candidate of theranostic system for combined photothermo-/chemo-cancer therapy.
Coherent-state storage and retrieval between superconducting cavities using parametric frequency conversion
Authors: Sirois A. J. , Castellanos-Beltran M. A. , DeFeo M. P. , Ranzani L. , Lecocq F. , Simmonds R. W. , Teufel J. D. , Aumentado J.
Published: April 2015

In superconducting quantum information, machined aluminum superconducting cavities have proven to be a well-controlled, low-dissipation electromagnetic environment for quantum circuits such as qubits. They can possess large internal quality factors, Qint > 108, and present the possibility of storing quantum information for times far exceeding those of microfabricated circuits. However, in order to be useful as a storage element, these cavities require a fast “read/write” mechanism—in other words, they require tunable coupling between other systems of interest such as other cavity modes and qubits, as well as any associated readout hardware. In this work, we demonstrate these qualities in a simple dual cavity architecture in which a low-Q “readout” mode is parametrically coupled to a high-Q “storage” mode, allowing us to store and retrieve classical information. Specifically, we employ a flux-driven Josephson junction-based coupling scheme to controllably swap coherent states between two cavities, demonstrating full, sequenced control over the coupling rates between modes.
Changes in the soil quality attributes of continuous no-till farming systems following a strategic tillage
Authors: Crawford M. H. , Rincon-Florez V. , Balzer A. , Dang Y. P. , Carvalhais L. C. , Liu H. , Schenk P. M.
Published: April 2015

The adoption of no-till farming systems has greatly reduced energy and machinery inputs while significantly improving soil health and productivity. However, the control of crop weeds and diseases in no-till (NT) systems has become increasingly difficult for landholders in Australia’s northern grains regions, with occasional strategic tillage (ST) being considered as a potential management option. This study investigated the effects of occasional ST on physical, chemical and biological soil properties, productivity, and weed control on five long-term (7–44 years) NT-managed soils. The study area extended from Biloela (Vertosol, 666 mm annual rainfall), Condamine (Sodosol, 624 mm annual rainfall), Moonie (Dermosol, 636 mm annual rainfall) and Warwick (Vertosol, 675 mm annual rainfall) in Queensland to Wee Waa (Vertosol, 582 mm annual rainfall) in New South Wales. Tillage treatments included chisel, offset disc and prickle–disc chain with various timings and frequencies. Soil samples (0–0.3 m) obtained 3 and 12 months after occasional ST were analysed for total and particulate organic carbon (TOC, POC), available phosphorus (P), bulk density, soil water, and microbial enzymatic activity. In-crop weed density was also recorded. One-time tillage, with chisel tines, offset disc or chain harrows, in long-term NT helped to control winter weeds in the first year, with variable results in the second year. Grain yield overall showed no significant impact in either year, except on the Brown Sodosol (P = 0.08) in the first year. The initial impacts of strategic tillage on soil water were largely restricted to the 0–0.1 m depth range, with slight, non-significant decreases occurring. Available P, TOC, POC and total microbial enzymatic activity were not significantly impacted by either cultivation frequency or implement type. The use of an occasional ST for the purpose of weed control could be utilised as a viable management option for NT systems in the region without impacting on long-term productivity.
Intercellular chaperone transmission via exosomes contributes to maintenance of protein homeostasis at the organismal level
Authors: Takeuchi Toshihide , Suzuki Mari , Fujikake Nobuhiro , Popiel H. Akiko , Kikuchi Hisae , Futaki Shiroh , Wada Keiji , Nagai Yoshitaka
Published: April 2015

Significance

The heat shock response (HSR), a transcriptional response that up-regulates molecular chaperones upon heat shock, is known to be activated in a cell type-specific manner. Despite such imbalanced HSR upon stress, it is unclear as to how organismal protein homeostasis (proteostasis) is maintained. Here, we show that elevated expression of molecular chaperones in cells non-cell autonomously improves proteostasis in other cells. We further show that exosome-mediated secretion and intercellular transmission of chaperones are responsible for this non–cell-autonomous improvement of proteostasis. Our study reveals a molecular mechanism of non–cell-autonomous maintenance of organismal proteostasis that could functionally compensate for the imbalanced HSR among different cells, and also provides a novel physiological function of exosomes that contributes to maintenance of proteostasis.
Missense mutation in immunodeficient patients shows the multifunctional roles of coiled-coil domain 3 (CC3) in STIM1 activation
Authors: Maus Mate , Jairaman Amit , Stathopulos Peter B. , Muik Martin , Fahrner Marc , Weidinger Carl , Benson Melina , Fuchs Sebastian , Ehl Stephan , Romanin Christoph , Ikura Mitsuhiko , Prakriya Murali , Feske Stefan
Published: April 2015

Significance

Stromal interaction molecule (STIM) 1 is an essential activator of the ORAI1 calcium (Ca
2+
) channel that mediates Ca
2+
entry into many cell types. Patients with mutations in
STIM1
or
ORAI1
genes suffer from a severe immunodeficiency syndrome. Here, we studied a disease-causing mutant of STIM1 that is incapable of activating ORAI1 channels, thereby uncovering key molecular mechanisms of STIM1 function. The autosomal recessive R429C mutation interferes with the structural integrity of a protein–protein interaction domain in STIM1 and impairs the ability of STIM1 to multimerize and bind to ORAI1. Drugs targeting this domain may provide a means to selectively modulate STIM1–ORAI1 interaction and Ca
2+
entry as a novel approach to treat autoimmune diseases and other disorders associated with abnormal ORAI1-mediated Ca
2+
entry.
Direct conversion of human fibroblasts into functional osteoblasts by defined factors
Authors: Yamamoto Kenta , Kishida Tsunao , Sato Yoshiki , Nishioka Keisuke , Ejima Akika , Fujiwara Hiroyoshi , Kubo Toshikazu , Yamamoto Toshiro , Kanamura Narisato , Mazda Osam
Published: April 2015

Significance

Osteoblasts produce bone matrix and contribute to bone remodeling. We have established a procedure to directly convert human fibroblasts into osteoblasts by transducing some defined factors and culturing in osteogenic medium. Osteoblast-specific transcription factors, Runx2 and Osterix, in combination with Oct4 and L-Myc, drastically induced fibroblasts to produce calcified bone matrix and express osteoblast-specific markers. The directly converted osteoblasts (dOBs) showed similar gene expression profiles as normal osteoblasts and contributed to bone repair after transplantation into mice with bone defects. Furthermore, dOBs did not require continuous expression of the exogenous genes to maintain their phenotype. These findings strongly suggest successful direct reprogramming of fibroblasts into osteoblasts, which may be applicable to bone regeneration therapy.
Coral symbiotic algae calcify
ex hospite
in partnership with bacteria
Authors: Frommlet Jörg C. , Sousa Maria L. , Alves Artur , Vieira Sandra I. , Suggett David J. , Serôdio João
Published: April 2015

Significance

The dinoflagellate genus
Symbiodinium
is best known for harboring important endosymbiotic algae of marine invertebrates, notably reef-building corals. However, these dinoflagellates also live freely within coral reef waters and sediments and provide an important environmental pool for the colonization of new coral recruits. Although
Symbiodinium
facilitate coral calcification indirectly when
in hospite
, we show that they also can calcify in partnership with bacteria when free living. This discovery offers entirely new perspectives on fundamental questions regarding the life cycle and ecology of these dinoflagellates and could help explain how changes in ocean chemistry created a selective pressure that ultimately led
Symbiodinium
to establish an endosymbiotic life style. To our knowledge, our findings document the first identified dinoflagellate–bacterial calcifying community.
How a well-adapted immune system is organized
Authors: Mayer Andreas , Balasubramanian Vijay , Mora Thierry , Walczak Aleksandra M.
Published: April 2015

Significance

The adaptive immune system uses the experience of past infections to prepare its limited repertoire of specialized receptors to protect organisms from future threats. What is the best way of doing this? Building a theoretical framework from first principles, we predict the composition of receptor repertoires that are optimally adapted to minimize the cost of infections from a given pathogenic environment. A naive repertoire can reach these optima through a biologically plausible competitive mechanism. Our findings explain how limited populations of immune receptors can self-organize to provide effective immunity against highly diverse pathogens. Our results also inform the design and interpretation of experiments surveying immune repertoires.
Event representations constrain the structure of language: Sign language as a window into universally accessible linguistic biases
Authors: Strickland Brent , Geraci Carlo , Chemla Emmanuel , Schlenker Philippe , Kelepir Meltem , Pfau Roland
Published: April 2015

Significance

One key issue in the study of human language is understanding what, if any, features of individual languages may be universally accessible. Sign languages offer a privileged perspective on this issue because the visual modality can help implement and detect certain properties that may be present but unmarked in spoken languages. The current work finds that fine-grained aspects of verb meanings visibly emerge across unrelated sign languages using identical mappings between meaning and visual form. Moreover, nonsigners lacking prior exposure to sign languages can intuit these meanings from entirely unfamiliar signs. This is highly suggestive that signers and nonsigners share universally accessible notions of telicity as well as universally accessible “mapping biases” between telicity and visual form.
Homologous
trans
-editing factors with broad tRNA specificity prevent mistranslation caused by serine/threonine misactivation
Authors: Liu Ziwei , Vargas-Rodriguez Oscar , Goto Yuki , Novoa Eva Maria , Ribas de Pouplana Lluís , Suga Hiroaki , Musier-Forsyth Karin
Published: April 2015

Significance

A key step in protein synthesis is catalyzed by aminoacyl-tRNA synthetases (ARSs), which attach specific amino acids to tRNAs. Errors caused by ARS amino acid misactivation require proofreading activities encoded in editing domains. Approximately half of the ARSs possess intrinsic editing functions, and single-domain editing proteins also are encoded in some organisms. The present study used an in vivo screen coupled with in vitro assays to elucidate the substrate specificity of two free-standing editing domains, revealing that they are multifunctional Ser/Thr-tRNA deacylases with the ability to prevent errors caused by a number of ARSs.
Trans
-editing proteins with broad substrate specificities provide a growth advantage to microbes under conditions in which amino acid pools are altered and may represent novel targets.
Enhancing ecosystem restoration efficiency through spatial and temporal coordination
Authors: Neeson Thomas M. , Ferris Michael C. , Diebel Matthew W. , Doran Patrick J. , O’Hanley Jesse R. , McIntyre Peter B.
Published: April 2015

Significance

Societies around the world make massive investments in ecosystem restoration projects to mitigate habitat loss, conserve biodiversity, and boost ecosystem services. We use a return-on-investment framework to assess the value of coordinating restoration efforts in space and time to maximize ecological connectivity between the Laurentian Great Lakes and their tributaries, which are fragmented by hundreds of thousands of dams and road crossings. We show that coordinating restoration efforts across the entire region is nine times more cost-effective than local-scale planning. Similarly, a single lump sum investment is up to 10 times more cost-effective than a series of annual allocations. These dramatic economic and ecological efficiencies provide ample incentive for coordinating conservation efforts across broad spatial and temporal scales.
Biological evidence supports an early and complex emergence of the Isthmus of Panama
Authors: Bacon Christine D. , Silvestro Daniele , Jaramillo Carlos , Smith Brian Tilston , Chakrabarty Prosanta , Antonelli Alexandre
Published: April 2015

Significance

The formation of the Isthmus of Panama, which linked North and South America, is key to understanding the biodiversity, oceanography, atmosphere, and climate in the region. Despite its importance across multiple disciplines, the timing of formation and emergence of the Isthmus and the biological patterns it created have been controversial. Here, we analyze molecular and fossil data, including terrestrial and marine organisms, to show that biotic migrations across the Isthmus of Panama began several million years earlier than commonly assumed. An earlier evolution of the Isthmus has broad implications for the mechanisms driving global climate (e.g., Pleistocene glaciations, thermohaline circulation) as well as the rich biodiversity of the Americas.
Transcriptome dynamics of developing maize leaves and genomewide prediction ofciselements and their cognate transcription factors
Authors: Yu Chun-Ping , Chen Sean Chun-Chang , Chang Yao-Ming , Liu Wen-Yu , Lin Hsin-Hung , Lin Jinn-Jy , Chen Hsiang June , Lu Yu-Ju , Wu Yi-Hsuan , Lu Mei-Yeh Jade , Lu Chen-Hua , Shih Arthur Chun-Chieh , Ku Maurice Sun-Ben , Shiu Shin-Han , Wu Shu-Hsing , Li Wen-Hsiung
Published: April 2015

Significance

Maize is a major crop and a model plant for studying C4 leaf development. However, its regulatory network of leaf development is poorly understood. We used transcriptomes of developing leaves to study gene-expression dynamics and coexpression to reveal functional transition during maize leaf development. More significantly, we developed methods to predict transcription factor-binding sites (TFBSs) and their cognate transcription factors (TFs) or to use the knownArabidopsisTF–TFBS pairs to predict the maize TF–TFBS pairs. In total, we predicted 1,340 novel TFBSs and 253 new TF–TFBS pairs in maize. Twelve predicted TF–TFBS interactions were validated by functional tests, suggesting that our methods perform well. Our study has significantly expanded our knowledge of the regulatory network of maize leaf development.
Strain and the optoelectronic properties of nonplanar phosphorene monolayers
Authors: Mehboudi Mehrshad , Utt Kainen , Terrones Humberto , Harriss Edmund O. , Pacheco SanJuan Alejandro A. , Barraza-Lopez Salvador
Published: April 2015

Significance

Phosphorene is a new 2D atomic material, and we document a drastic reduction of its electronic gap when under a conical shape. Furthermore, geometry determines the properties of 2D materials, and we introduce discrete differential geometry to study them. This geometry arises from particle/atomic positions; it is not based on a parametric continuum, and it applies across broad disciplinary lines.
Nonsense suppression in archaea
Authors: Bhattacharya Arpita , Köhrer Caroline , Mandal Debabrata , RajBhandary Uttam L.
Published: April 2015

Significance

Three stop codons are used as translation termination signals within the mRNA. Nonsense suppression is defined as the read through of stop codons in an mRNA by a class of mutant tRNAs called nonsense suppressor tRNAs. Although much is known about nonsense suppression in bacteria (e.g.,
Escherichia coli
) and eukaryotes (e.g., yeast) and although suppressor tRNAs have served as invaluable tools in bacterial and bacterial viral genetics, very little is known about nonsense suppression in archaea, the third kingdom of life. We describe here for the first time, to our knowledge, the suppression of all three stop codons in
Haloferax volcanii
, a halophilic archaeon, by suppressor tRNAs derived from serine or tyrosine tRNA.
Completion of the seven-step pathway from tabersonine to the anticancer drug precursor vindoline and its assembly in yeast
Authors: Qu Yang , Easson Michael L. A. E. , Froese Jordan , Simionescu Razvan , Hudlicky Tomas , De Luca Vincenzo
Published: April 2015

Significance

Bioinformatics and virus-induced gene silencing (VIGS)-guided gene discovery combined with biochemical enzyme assays show that tabersonine 3-oxygenase (T3O) and tabersonine 3-reductase (T3R) are required to form 3-hydroxy-16-methoxy-2,3-dihydrotabersonine, an intermediate in the formation of anticancer drug precursor vindoline from tabersonine. In the absence of T3R, tabersonine is converted by T3O to a series of byproducts that can no longer be used by T3R, suggesting a concerted reaction mechanism. Engineering the seven-gene pathway in yeast demonstrated a prototype platform of high potential for industrial production of the anticancer drug precursor vindoline.
Targeting β-arrestin2 in the treatment ofl-DOPA–induced dyskinesia in Parkinson’s disease
Authors: Urs Nikhil M. , Bido Simone , Peterson Sean M. , Daigle Tanya L. , Bass Caroline E. , Gainetdinov Raul R. , Bezard Erwan , Caron Marc G.
Published: April 2015

Significance

β-Arrestins are unique proteins that have multiple cellular functions such as G protein-coupled receptor signal desensitization, protein trafficking and signaling molecule scaffolding. Treatment of Parkinson’s disease (PD) motor symptoms byl-3,4-dihydroxyphenylalanine (l-DOPA) has been hampered by abnormal involuntary movements or dyskinetic side effects. The cause of these dyskinesias has been attributed to receptor supersensitivity and uncontrolled neuronal excitability. Here we demonstrate in multiple preclinical models ofl-DOPA–induced dyskinesias and PD that expression levels of β-arrestin2 can alter manifestation of these dyskinesias by reducing receptor supersensitivity while maintaining the therapeutic effect ofl-DOPA. Thus novel drugs that increase β-arrestin–dependent function at dopamine receptors may be useful in ameliorating PD motor symptoms without inducing dyskinesias.
A ΩX
a
V motif in the Rift Valley fever virus NSs protein is essential for degrading p62, forming nuclear filaments and virulence
Authors: Cyr Normand , de la Fuente Cynthia , Lecoq Lauriane , Guendel Irene , Chabot Philippe R. , Kehn-Hall Kylene , Omichinski James G.
Published: April 2015

Significance

Infection with the Rift Valley fever virus (RVFV) has the capacity to cause fatal hemorrhagic fever in humans. A unique characteristic of RVFV infection is the presence of nuclear filaments whose formation is linked to synthesis of the viral NSs protein. We identify a crucial interaction between a ΩX
a
V motif present in the NSs protein and the p62 subunit of the host TFIIH. This interaction is required for nuclear filament formation, NSs-dependent degradation of p62 and for virulence. This ΩX
a
V motif is also found in human proteins that bind p62 and our results are an example of how viruses incorporate simple motifs into their protein sequences to mimic human proteins and enhance their functional capabilities in host cells during infections.
iRhoms 1 and 2 are essential upstream regulators of ADAM17-dependent EGFR signaling
Authors: Li Xue , Maretzky Thorsten , Weskamp Gisela , Monette Sébastien , Qing Xiaoping , Issuree Priya Darshinee A. , Crawford Howard C. , McIlwain David R. , Mak Tak W. , Salmon Jane E. , Blobel Carl P.
Published: April 2015

Significance

The skin and intestinal barrier are controlled by signaling scissors, termed ADAM17 (a disintegrin and metalloprotease 17), that reside in the membrane on the surface of cells. The main purpose of these signaling scissors is to liberate growth factors from their membrane anchor, allowing them to activate their receptors, including the epidermal growth factor receptor (EGFR). The ADAM17/EGFR signaling axis is tightly regulated, yet little is known about the underlying mechanism. Here we use genetic, cell biological, and biochemical approaches to identify two membrane proteins termed iRhoms 1 and 2 (inactive Rhomboid-like proteins) as crucial upstream regulators of ADAM17-dependent EGFR signaling. This uncovers the iRhoms as attractive novel targets to treat ADAM17/EGFR-dependent diseases such as cancer.