bluuebunny/crossref_metadata_2025 huggingface dataset:
Lipocalin2 as a plasma marker for tumors with hypoxic regions
Authors: Nakamura Ibuki , Hama Susumu , Itakura Shoko , Takasaki Ichiro , Nishi Takayuki , Tabuchi Yoshiaki , Kogure Kentaro
Published: December 2014

Hypoxic tumors have been identified as appropriate indicators of tumor malignancy. However, no convenient plasma marker for hypoxic tumors has been described. Therefore, to identify a novel, convenient plasma marker for hypoxic tumors, we used microarray analysis to compare gene expression profiles of normoxic and hypoxic tumor tissues of mice bearing melanomas. Among the upregulated genes detected in hypoxic tumors, we chose to study the secretory protein lipocalin2 (LCN2) as a marker for hypoxic tumors. LCN2 protein levels in the plasma of mice bearing hypoxic tumors were significantly increased compared with those in mice bearing normoxic tumors. Interestingly,LCN2mRNA levels were 17-fold higher in HIF-1α-positive hypoxic tumors than in HIF-1α-negative normoxic tumors. Furthermore,LCN2mRNA levels were significantly higher in the B16-F1 cells and various human tumor cells cultured under hypoxic conditions than in cells cultured under normoxic conditions, while no changes in mRNA expression were observed in nontumor NIH-3T3 cells, even under hypoxic conditions. In cultured cells, the expression pattern ofLCN2was mostly consistent with that of HIF-1α, whereas that of a conventional hypoxic marker, carbonic anhydrase IX, was not. Collectively, our data suggested that LCN2 was a useful plasma marker for hypoxic tumors.
PNGase F-mediated incorporation of18O into glycans for relative glycan quantitation
Authors: Zhang Wei , Cao Weiqian , Huang Jiangming , Wang Hong , Wang Ji , Xie Chen , Yang Pengyuan
Published: December 2014

An enzymatic four18O-labeling strategy based on PNGase F-catalyzed glycan18O-labeling (PCGOL) developed in this work can be used for simultaneous quantification of glycans, non-glycopeptides and glycopeptides in a single workflow.
Direct detection of microRNA based on plasmon hybridization of nanoparticle dimers
Authors: Wang Yang , MacLachlan Elspeth , Nguyen Bach Kim , Fu Guodong , Peng Chun , Chen Jennifer I. L.
Published: December 2014

We demonstrate the direct detection of microRNA-210, a biomarker for hypoxia-related diseases, in cellular RNA extracts and cell media using discrete actuatable plasmonic nanoparticle dimers.
Gold finger formation studied by high-resolution mass spectrometry and in silico methods
Authors: Laskay Ü. A. , Garino C. , Tsybin Y. O. , Salassa L. , Casini A.
Published: December 2014

Combining high-resolution MS and QM/MM studies to investigate the reactivity of gold compounds with zinc finger domains at a molecular level.
Sticky tubes and magnetic hydrogels co-assembled by a short peptide and melanin-like nanoparticles
Authors: Das Priyadip , Yuran Sivan , Yan Jian , Lee Pooi See , Reches Meital
Published: December 2014

The co-assembly of peptide monomers and polydopamine-based nanoparticles leads to the formation of either tubular structures decorated with adhesive particles or magnetic hydrogel.
A novel supramolecular metallogel-based high-resolution anion sensor array
Authors: Lin Qi , Lu Tao-Tao , Zhu Xin , Sun Bin , Yang Qing-Ping , Wei Tai-Bao , Zhang You-Ming
Published: December 2014

A novel anion sensor array based on supramolecular metallogels has been developed. The sensor array could accurately identify CN−, SCN−, S2−and I−in water. Interestingly, the metallogel-based sensor array needs only one synthesized gelatorG1.
Detection of oligomers and fibrils of α-synuclein by AIEgen with strong fluorescence
Authors: Leung Chris Wai Tung , Guo Feng , Hong Yuning , Zhao Engui , Kwok Ryan Tsz Kin , Leung Nelson Lik Ching , Chen Sijie , Vaikath Nishant N. , El-Agnaf Omar Mukhtar , Tang Youhong , Gai Wei-Ping , Tang Ben Zhong
Published: December 2014

Fluorescent probe, TPE-TPP, can differentiate monomeric, oligomeric and fibrillar α-synuclein which was previously difficult to achieve.
Myoglobin-catalyzed intermolecular carbene N–H insertion with arylamine substrates
Authors: Sreenilayam Gopeekrishnan , Fasan Rudi
Published: December 2014

Engineered variants of sperm whale myoglobin efficiently catalyze the insertion of α-diazo esters into the N–H bond of arylamines, featuring a combination of high chemoselectivity, elevated turnover numbers, and broad substrate scope.
Translation of the assembling trajectory by preorganisation: a study of the magnetic properties of 1D polymeric unpaired electrons immobilised on a discrete nanoscopic scaffold
Authors: Praveen Vakayil K. , Yamamoto Yohei , Fukushima Takanori , Tsunobuchi Yoshihide , Nakabayashi Koji , Ohkoshi Shin-ichi , Kato Kenichi , Takata Masaki , Aida Takuzo
Published: December 2014

HBCNN, when allowed to coassemble with Co(hfac)2, forms a coaxial nanotube, which has enhanced magnetic susceptibility below 10 K.
Graphene mediated self-assembly of fullerene nanorods
Authors: Gnanaprakasa Tony J. , Sridhar Deepak , Beck Warren J. , Runge Keith , Potter Barrett G. , Zega Thomas J. , Deymier Pierre A. , Raghavan Srini , Muralidharan Krishna
Published: December 2014

A simple procedure for solution-based self-assembly of C60 fullerene nanorods on graphene substrates is presented.
Fundamental frequency from classical molecular dynamics
Authors: Yamada Tomonori , Aida Misako
Published: December 2014

We give a theoretical validation of for calculating fundamental frequencies of a molecule from classical molecular dynamics (MD) when its anharmonicity is small enough to be treated by perturbation theory.
Analysis of computational models for an accurate study of electronic excitations in GFP
Authors: Schwabe Tobias , Beerepoot Maarten T. P. , Olsen Jógvan Magnus Haugaard , Kongsted Jacob
Published: December 2014

The accuracy of PERI-CC2 is successfully assessed against RVS-CC2 for GFP model clusters and subsequently applied to a whole protein model.
Behaviour and mobility of U and Ra in sediments near an abandoned uranium mine, Cornwall, UK
Authors: Siddeeg Saifeldin M. , Bryan Nicholas D. , Livens Francis R.
Published: December 2014

Sediment samples were collected from the vicinity of the abandoned South Terras uranium mine in south-west UK and analysed for uranium and 226Ra to explore their geochemical dispersion.
Highly efficient construction of a bridged pentacyclic skeleton via a six-component domino reaction under microwave irradiation
Authors: Fu Lei , Feng Xian , Zhang Juan-Juan , Hu Jun-Die , Xun Zhan , Wang Jian-Jun , Huang Zhi-Bin , Shi Da-Qing
Published: December 2014

A bridged pentacyclic skeleton has been constructed via a six-component domino reaction under microwave irradiation.
Design, synthesis and biological evaluation of imidazopyridine/imidazopyrimidine-benzimidazole conjugates as potential anticancer agents
Authors: Kamal Ahmed , Bharath Kumar G. , Lakshma Nayak V. , Reddy Vangala Santhosh , Shaik Anver Basha , Rajender Rajender , Kashi Reddy M.
Published: December 2014

A series of imidazopyridine/imidazopyrimidine-benzimidazole conjugates (11a–t) were synthesized and evaluated for their antiproliferative activity.
Surface-enhanced spectroscopy on plasmonic oligomers assembled by AFM nanoxerography
Authors: Moutet Pierre , Sangeetha Neralagatta M. , Ressier Laurence , Vilar-Vidal Noelia , Comesaña-Hermo Miguel , Ravaine Serge , Vallée Renaud A. L. , Gabudean Ana Maria , Astilean Simion , Farcau Cosmin
Published: December 2014

Experimental and theoretical findings on SERS and SEF of plasmonic nanoparticle oligomers foster a common framework for these optical phenomena.
Submicron polyacrolein particles in situ embedded with upconversion nanoparticles for bioassay
Authors: Generalova A. N. , Kochneva I. K. , Khaydukov E. V. , Semchishen V. A. , Guller A. E. , Nechaev A. V. , Shekhter A. B. , Zubov V. P. , Zvyagin A. V. , Deyev S. M.
Published: December 2014

We report a new surface modification of upconversion nanoparticles based on their encapsulation in the course of acrolein polymerization and demonstrate their in vivo application.
Trigonal scaffolds for multivalent targeting of melanocortin receptors
Authors: Elshan N. G. R. Dayan , Jayasundera Thanuja , Anglin Bobbi L. , Weber Craig S. , Lynch Ronald M. , Mash Eugene A.
Published: December 2014

Short, efficient syntheses of multivalent molecules targeted to the human melanocortin 4 receptor based on phloroglucinol, tripropargylamine, and 1,4,7-triazacyclononane are described.
A Sc(OTf)3-catalyzed cascade reaction of o-aminoacetophenone with methanamine: construction of dibenzo[b,h][1,6]naphthyridine derivatives
Authors: Mao Dan , Tang Jun , Wang Wenbo , Liu Xin , Wu Shengying , Yu Jianjun , Wang Limin
Published: December 2014

A Sc(OTf)3-catalyzed and air-mediated cascade reaction was discovered as an efficient approach to the novel fluorescent fused-four-ring dibenzo[b,h][1,6]naphthyridine derivatives.
Phosphate binding by a novel Zn(ii) complex featuring a trans-1,2-diaminocyclohexane ligand. Effective anion recognition in water
Authors: Francesconi Oscar , Gentili Matteo , Bartoli Francesco , Bencini Andrea , Conti Luca , Giorgi Claudia , Roelens Stefano
Published: December 2014

Excellent affinities and selectivities toward triphosphates are achieved through an adaptive ditopic receptor featuring a metal ion and a macrocyclic polyammonium cation binding sites, concertedly bridging phosphate anions.
Synthesis of surface ion-imprinted magnetic microspheres by locating polymerization for rapid and selective separation of uranium(vi)
Authors: Qian Jun , Zhang Shuang , Zhou Yuan , Dong Ping , Hua Daoben
Published: December 2014

New surface ion-imprinted magnetic microspheres are developed by locating polymerization for uranium(vi) adsorption with ultrafast kinetics and high selectivity.
Nucleation and growth orientation of zinc electrocrystallization in the presence of gelatin in Zn(ii)–NH3–NH4Cl–H2O electrolytes
Authors: Xia Zhimei , Yang Shenghai , Tang MoTang
Published: December 2014

Nucleation and growth orientation of zinc electrocrystallization in the presence of gelatin in Zn(ii)–NH3–NH4Cl–H2O solutions were studied.
Enhanced field emission properties based on In–In2O3 composite nanopagodas
Authors: Wang Sin-Hui , Liu Shin , Chang Shoou-Jinn , Tsai Tsung-Ying , Hsu Cheng-Liang
Published: December 2014

In–In2O3 composite nanopagodas demonstrate excellent field emission properties with an enhanced kinetics factor (saturation ratio).
Simplified phosphorescent organic light-emitting devices using heavy doping with an Ir complex as an emitter
Authors: Miao Yanqin , Du Xiaogang , Wang Hua , Liu Huihui , Jia Husheng , Xu Bingshe , Hao Yuying , Liu Xuguang , Li Wenlian , Huang Wei
Published: December 2014

Simplified PhOLEDs based on heavy doping with the light-emitting layer (EML) of CBP: 25 wt% Ir(ppy)3 (30 nm) shows a peak current efficiency of 46.8 cd A−1, which is 1.64 times that of the reference device with the EML of CBP: 8 wt% Ir(ppy)3 (30 nm).
Correction: Prediabetes: grounds of pitfall signalling alteration for cardiovascular disease
Authors: Goyal Sameer N. , Sharma Arun Kumar , Haiderali Shaikh , Reddy M Navya , Arya Dharamvir Singh , Patil Chandragouda R.
Published: December 2014

Correction for ‘Prediabetes: grounds of pitfall signalling alteration for cardiovascular disease’ by Sameer N. Goyal et al., RSC Adv., 2014, 4, 58272–58279.
Identification of a fluorometabolite from Streptomyces sp. MA37: (2R3S4S)-5-fluoro-2,3,4-trihydroxypentanoic acid
Authors: Ma Long , Bartholome Axel , Tong Ming Him , Qin Zhiwei , Yu Yi , Shepherd Thomas , Kyeremeh Kwaku , Deng Hai , O'Hagan David
Published: December 2014

(2R3S4S)-5-Fluoro-2,3,4-trihydroxypentanoic acid (5-FHPA) has been discovered as a new fluorometabolite in the soil bacterium Streptomyces sp. MA37.
Transition from diffusive to subdiffusive motion in colloidal liquids
Authors: Sánchez-Miranda M. J. , Bonilla-Capilla B. , Sarmiento-Gómez E. , Lázaro-Lázaro E. , Ramírez-Saito A. , Medina-Noyola M. , Arauz-Lara J. L.
Published: December 2014

In this work we report experimental and theoretical results for the motion of single colloidal particles embedded in complex fluids with different interparticle interactions.
Modulation of friction dynamics in water by changing the combination of the loop- and graft-type poly(ethylene glycol) surfaces
Authors: Seo Ji-Hun , Tsutsumi Yusuke , Kobari Akinori , Shimojo Masayuki , Hanawa Takao , Yui Nobuhiko
Published: December 2014

A Velcro-like poly(ethylene glycol) (PEG) interface was prepared in order to control the friction dynamics of material surfaces.
A molecular breakwater-like tetrapod for organic solar cells
Authors: Yang Jianzhong , He Wenhan , Denman Kimberly , Jiang Ying-Bing , Qin Yang
Published: December 2014

The tetrahedral geometry of the conjugated small molecule displays unique thermal properties that lead to distinct behaviors in binary and ternary blend organic solar cells.
Inkjet printing of CH3NH3PbI3on a mesoscopic TiO2film for highly efficient perovskite solar cells
Authors: Li Shao-Gang , Jiang Ke-Jian , Su Mei-Ju , Cui Xue-Ping , Huang Jin-Hua , Zhang Qian-Qian , Zhou Xue-Qin , Yang Lian-Min , Song Yan-Lin
Published: December 2014

CH3NH3PbI3is deposited as a light absorber on a mesoporous TiO2film and the structure and morphology are investigated at different table temperatures and with various amounts of added CH3NH3Cl. The optimized device exhibits the highest power conversion efficiency of 12.3% with an average value of 11.2%.
Zinc–cobalt oxides as efficient water oxidation catalysts: the promotion effect of ZnO
Authors: Rong Feng , Zhao Jiao , Su Panpan , Yao Yi , Li Mingrun , Yang Qihua , Li Can
Published: December 2014

ZnO and Co3O4 in the interface of zinc–cobalt oxides work in a cooperative way as a water adsorption site and water oxidation site, respectively.
Conjugated polymer microparticles for selective cancer cell image-guided photothermal therapy
Authors: Feng Guangxue , Liu Jie , Geng Junlong , Liu Bin
Published: December 2014

We report conjugated polymers (CPs) microparticles (MPs) for selective cancer cell image-guided photothermal therapy. The CPMPs without surface functionalization can target MCF-7 cancer cells over NIH-3T3 normal cells, while nanoparticles need surface decoration to possess selectivity. Benefitting from large absorption, bright fluorescence, and efficient light-to-heat conversion of CPs, the fabricated MPs can selectively kill MCF-7 cells under NIR infrared laser irradiation.
Performance enhancement of mapping multiplexing technique utilising dual‐drive Mach–Zehnder modulator for metropolitan area networks
Authors: Elsherif Mohamed A. , Malekmohammadi Amin
Published: December 2014

A methodology to control the eye opening distribution of mapping multiplexing technique (MMT) system is proposed and presented. The authors modelled and analysed a method to enhance the receiver sensitivity of MMT system by using optimised dual‐drive Mach–Zehnder modulator. The proposed method offers larger eye opening for distorted Level‐3 eyes. Based on the numerical calculation, the optimisation leads toward minimal eye closure. The performance of proposed system is shown to be improved by 6.1 dB in terms of receiver sensitivity compared with the conventional MMT system. Throughout the paper, the authors also discuss a numerical comparative analysis between the proposed MMT model, conventional MMT model, 33% return‐to‐zero on–off‐keying (33%RZ‐OOK), 50% RZ‐OOK, 67% carrier‐suppressed RZ‐OOK and 4‐ary amplitude shift keying in terms of positive chromatic dispersion tolerance and spectral efficiency.
On‐line identification of biomass fuels based on flame radical imaging and application of radical basis function neural network techniques
Authors: Li Xinli , Wu Mengjiao , Lu Gang , Yan Yong , Liu Shi
Published: December 2014

In biomass fired power plants a range of biomass fuels are used to generate electric power. It is desirable to identify the type of biomass fuels on‐line continuously in order to achieve an improved combustion efficiency, and reduced pollutant emissions. This paper presents the recent investigations into the on‐line identification of biomass fuels based on the combination of flame radical imaging and radical basis function (RBF) neural network (NN) techniques. The characteristic values of flame radicals (OH*, CN*, CH* and C2*), including the intensity ratio, intensity contour, mean intensity, area and eccentricity, are computed to reconstruct two types of RBF NN, that is, accurate and probabilistic RBF networks. Experimental results obtained for three types of biomass fuels (flour, willow sawdust and palm kernel shell) firing on a laboratory‐scale combustion test rig are presented to demonstrate the effectiveness of the proposed method.
Preparation of water‐dispersible TiO2 nanoparticles
Authors: Kang Shi‐Zhao , Yin Dieer , Li Xiangqing , Zhang Qiang , Mu Jin
Published: December 2014

Water‐dispersible TiO2 nanoparticles with narrow size distribution and good crystallinity were synthesised in a solvothermal process using lactic acid as the capping agent. X‐ray diffraction, transmission electron microscopy and nitrogen adsorption–desorption isotherm were used to characterise the products. Meanwhile, the dispersion behaviour of the as‐prepared TiO2 nanoparticles was investigated. The as‐prepared powder can be easily redispersed in water to form a stable solution‐like suspension with a concentration of 60 mg·ml−1. Moreover, the dispersion mechanism was also preliminarily discussed, suggesting that the excellent dispersibility of the as‐prepared TiO2 nanoparticles is probably because of electrostatic repulsion from lactic acid molecules covalently linked to TiO2 nanoparticles.
Das Konzept der Validationstherapie nach Naomi Feil bei Patienten mit
demenziellen Erkrankungen in der neurologischen Rehabilitation
Authors: Blümner Kristina , Bsdok Katja
Published: December 2014

Aufgrund der stetig steigenden Lebenserwartung in den Industrieländern steigt
auch in Deutschland der Versorgungs- und Pflegebedarf enorm an. Ein Großteil des
zukünftigen Bedarfs wird durch die Demenzerkrankungen verursacht. Daher bedarf
es einer Optimierung der Pflege- und Versorgungskonzepte. Ein solches auf die
Bedürfnisse von Demenzkranken ausgerichtetes optimiertes Versorgungskonzept ist
die Validationstherapie.
Simulations of the L-H transition on experimental advanced superconducting Tokamak
Authors: Weiland Jan
Published: December 2014

We have simulated the L-H transition on the EAST tokamak [Baonian Wan, EAST and HT-7 Teams, and International Collaborators, “Recent experiments in the EAST and HT-7 superconducting tokamaks,” Nucl. Fusion 49, 104011 (2009)] using a predictive transport code where ion and electron temperatures, electron density, and poloidal and toroidal momenta are simulated self consistently. This is, as far as we know, the first theory based simulation of an L-H transition including the whole radius and not making any assumptions about where the barrier should be formed. Another remarkable feature is that we get H-mode gradients in agreement with the α – αd diagram of Rogers et al. [Phys. Rev. Lett. 81, 4396 (1998)]. Then, the feedback loop emerging from the simulations means that the L-H power threshold increases with the temperature at the separatrix. This is a main feature of the C-mod experiments [Hubbard et al., Phys. Plasmas 14, 056109 (2007)]. This is also why the power threshold depends on the direction of the grad B drift in the scrape off layer and also why the power threshold increases with the magnetic field. A further significant general H-mode feature is that the density is much flatter in H-mode than in L-mode.
A master equation and moment approach for biochemical systems with creation-time-dependent bimolecular rate functions
Authors: Chevalier Michael W. , El-Samad Hana
Published: December 2014

Noise and stochasticity are fundamental to biology and derive from the very nature of biochemical reactions where thermal motion of molecules translates into randomness in the sequence and timing of reactions. This randomness leads to cell-to-cell variability even in clonal populations. Stochastic biochemical networks have been traditionally modeled as continuous-time discrete-state Markov processes whose probability density functions evolve according to a chemical master equation (CME). In diffusion reaction systems on membranes, the Markov formalism, which assumes constant reaction propensities is not directly appropriate. This is because the instantaneous propensity for a diffusion reaction to occur depends on the creation times of the molecules involved. In this work, we develop a chemical master equation for systems of this type. While this new CME is computationally intractable, we make rational dimensional reductions to form an approximate equation, whose moments are also derived and are shown to yield efficient, accurate results. This new framework forms a more general approach than the Markov CME and expands upon the realm of possible stochastic biochemical systems that can be efficiently modeled.
Towards a unified description of the hydrogen bond network of liquid water: A dynamics based approach
Authors: Ozkanlar Abdullah , Zhou Tiecheng , Clark Aurora E.
Published: December 2014

The definition of a hydrogen bond (H-bond) is intimately related to the topological and dynamic properties of the hydrogen bond network within liquid water. The development of a universal H-bond definition for water is an active area of research as it would remove many ambiguities in the network properties that derive from the fixed definition employed to assign whether a water dimer is hydrogen bonded. This work investigates the impact that an electronic-structure based definition, an energetic, and a geometric definition of the H-bond has upon both topological and dynamic network behavior of simulated water. In each definition, the use of a cutoff (either geometric or energetic) to assign the presence of a H-bond leads to the formation of transiently bonded or broken dimers, which have been quantified within the simulation data. The relative concentration of transient species, and their duration, results in two of the three definitions sharing similarities in either topological or dynamic features (H-bond distribution, H-bond lifetime, etc.), however no two definitions exhibit similar behavior for both classes of network properties. In fact, two networks with similar local network topology (as indicated by similar average H-bonds) can have dramatically different global network topology (as indicated by the defect state distributions) and altered H-bond lifetimes. A dynamics based correction scheme is then used to remove artificially transient H-bonds and to repair artificially broken bonds within the network such that the corrected network exhibits the same structural and dynamic properties for two H-bond definitions (the properties of the third definition being significantly improved). The algorithm described represents a significant step forward in the development of a unified hydrogen bond network whose properties are independent of the original hydrogen bond definition that is employed.
Ab initio study of electron-ion structure factors in binary liquids with different types of chemical bonding
Authors: Klevets Ivan , Bryk Taras
Published: December 2014

Electron-ion structure factors, calculated in ab initio molecular dynamics simulations, are reported for several binary liquids with different kinds of chemical bonding: metallic liquid alloy Bi–Pb, molten salt RbF, and liquid water. We derive analytical expressions for the long-wavelength asymptotes of the partial electron-ion structure factors of binary systems and show that the analytical results are in good agreement with the ab initio simulation data. The long-wavelength behaviour of the total charge structure factors for the three binary liquids is discussed.
A real-time laser feedback control method for the three-wave laser source used in the polarimeter-interferometer diagnostic on Joint-TEXT tokamak
Authors: Xiong C. Y. , Chen J. , Li Q. , Liu Y. , Gao L.
Published: December 2014

A three-wave laser polarimeter-interferometer, equipped with three independent far-infrared laser sources, has been developed on Joint-TEXT (J-TEXT) tokamak. The diagnostic system is capable of high-resolution temporal and phase measurement of the Faraday angle and line-integrated density. However, for long-term operation (>10 min), the free-running lasers can lead to large drifts of the intermediate frequencies (∼100–∼500 kHz/10 min) and decay of laser power (∼10%–∼20%/10 min), which act to degrade diagnostic performance. In addition, these effects lead to increased maintenance cost and limit measurement applicability to long pulse/steady state experiments. To solve this problem, a real-time feedback control method of the laser source is proposed. By accurately controlling the length of each laser cavity, both the intermediate frequencies and laser power can be simultaneously controlled: the intermediate frequencies are controlled according to the pre-set values, while the laser powers are maintained at an optimal level. Based on this approach, a real-time feedback control system has been developed and applied on J-TEXT polarimeter-interferometer. Long-term (theoretically no time limit) feedback of intermediate frequencies (maximum change less than ±12 kHz) and laser powers (maximum relative power change less than ±7%) has been successfully achieved.
Calculation of the electron spin relaxation times in InSb and InAs by the projection-reduction method
Authors: Kang Nam Lyong
Published: December 2014

The electron spin relaxation times in a system of electrons interacting with piezoelectric phonons mediated through spin-orbit interactions were calculated using the formula derived from the projection-reduction method. The results showed that the temperature and magnetic field dependence of the relaxation times in InSb and InAs were similar. The piezoelectric material constants obtained by a comparison with the reported experimental result were Ppe=4.0×1022 eV/m for InSb and Ppe=1.2×1023 eV/m for InAs. The result also showed that the relaxation of the electron spin by the Elliot-Yafet process is more relevant for InSb than InAs at a low density.
Mathematical modeling of a four-stroke resonant engine for micro and mesoscale applications
Authors: Preetham B. S. , Anderson M. , Richards C.
Published: December 2014

In order to mitigate frictional and leakage losses in small scale engines, a compliant engine design is proposed in which the piston in cylinder arrangement is replaced by a flexible cavity. A physics-based nonlinear lumped-parameter model is derived to predict the performance of a prototype engine. The model showed that the engine performance depends on input parameters, such as heat input, heat loss, and load on the engine. A sample simulation for a reference engine with octane fuel/air ratio of 0.043 resulted in an indicated thermal efficiency of 41.2%. For a fixed fuel/air ratio, higher output power is obtained for smaller loads and vice-versa. The heat loss from the engine and the work done on the engine during the intake stroke are found to decrease the indicated thermal efficiency. The ratio of friction work to indicated work in the prototype engine is about 8%, which is smaller in comparison to the traditional reciprocating engines.
Monitoring the dielectric response of single cells following mitochondrial adenosine triphosphate synthase inhibition by oligomycin using a dielectrophoretic cytometer
Authors: Saboktakin Rizi B. , Braasch K. , Salimi E. , Butler M. , Bridges G. E. , Thomson D. J.
Published: December 2014

One of the main uses of adenosine triphosphate (ATP) within mammalian cells is powering the Na+/K+ ATPase pumps used to maintain ion concentrations within the cell. Since ion concentrations determine the cytoplasm conductivity, ATP concentration is expected to play a key role in controlling the cytoplasm conductivity. The two major ATP production pathways within cells are via glycolysis within the cytoplasm and via the electron transport chain within the mitochondria. In this work, a differential detector combined with dielectrophoretic (DEP) translation in a microfluidic channel was employed to observe single cell changes in the cytoplasm conductivity. The DEP response was made sensitive to changes in cytoplasm conductivity by measuring DEP response versus media conductivity and using double shell models to choose appropriate frequencies and media conductivity. Dielectric response of Chinese hamster ovary (CHO) cells was monitored following inhibition of the mitochondria ATP production by treatment with oligomycin. We show that in CHO cells following exposure to oligomycin (8 μg/ml) the cytoplasm conductivity drops, with the majority of the change occurring within 50 min. This work demonstrates that dielectric effects due to changes in ATP production can be observed at the single cell level.
Low frequency noise peak near magnon emission energy in magnetic tunnel junctions
Authors: Liu Liang , Xiang Li , Guo Huiqiang , Wei Jian , Li D. L. , Yuan Z. H. , Feng J. F. , Han X. F. , Coey J. M. D.
Published: December 2014

We report on the low frequency (LF) noise measurements in magnetic tunnel junctions (MTJs) below 4 K and at low bias, where the transport is strongly affected by scattering with magnons emitted by hot tunnelling electrons, as thermal activation of magnons from the environment is suppressed. For both CoFeB/MgO/CoFeB and CoFeB/AlOx/CoFeB MTJs, enhanced LF noise is observed at bias voltage around magnon emission energy, forming a peak in the bias dependence of noise power spectra density, independent of magnetic configurations. The noise peak is much higher and broader for unannealed AlOx-based MTJ, and besides Lorentzian shape noise spectra in the frequency domain, random telegraph noise (RTN) is visible in the time traces. During repeated measurements the noise peak reduces and the RTN becomes difficult to resolve, suggesting defects being annealed. The Lorentzian shape noise spectra can be fitted with bias-dependent activation of RTN, with the attempt frequency in the MHz range, consistent with magnon dynamics. These findings suggest magnon-assisted activation of defects as the origin of the enhanced LF noise.
Highly efficient terahertz wave filter for high-power laser beam separation
Authors: Guo Bo , Tang Jun , Cai Bin , Zhu YiMing
Published: December 2014

In this study, we design and fabricate a two-layer device based on the Rayleigh scattering theory for effectively separating high-energy pump-laser-generated terahertz (THz) waves. The basic layer is comprised of cyclo olefin polymer and silicon nanoparticles, which can obstruct the propagation of the 800-nm, high-energy pump laser through scattering and absorption effects while permitting THz waves to pass through. In order to improve the laser damage threshold of the basic layer, an additional layer, which is composed of hollow silica nanoparticles, is used to diffuse the incident high-energy laser beam. Through this two-layer structure, a high 800-nm laser threshold and highly transparent THz region filter are fabricated.
Controllable growth and optical properties of InP and InP/InAs nanostructures on the sidewalls of GaAs nanowires
Authors: Yan Xin , Zhang Xia , Li Junshuai , Cui Jiangong , Ren Xiaomin
Published: December 2014

The growth and optical properties of InP and InP/InAs nanostructures on GaAs nanowires are investigated. InP quantum well and quantum dots (QDs) are formed on the sidewalls of GaAs nanowires successively with increasing the deposition time of InP. The GaAs/InP nanowire heterostructure exhibits a type-II band alignment. The wavelength of the InP quantum well is in the range of 857–892 nm at 77 K, which means that the quantum well is nearly fully strained. The InP quantum dot, which has a bow-shaped cross section, exhibits dislocation-free pure zinc blende structure. Stranski-Krastanow InAs quantum dots are subsequently formed on the GaAs/InP nanowire core-shell structure. The InAs quantum dots are distributed over the middle part of the nanowire, indicating that the In atoms contributing to the quantum dots mainly come from the vapor rather than the substrate. The longest emission wavelength obtained from the InAs QDs is 1039 nm at 77 K. The linewidth is as narrow as 46.3 meV, which is much narrower than those on planar InP substrates and wurtzite InP nanowires, suggesting high-crystal-quality, phase-purity, and size-uniformity of quantum dots.
Thatcher's Britain: A New Take on an Old Illusion
Authors: Johnston Patrick , Baker Daniel H , Stone Rob , Kaufman Jordy
Published: December 2014

The Thatcher Illusion is generally discussed as a phenomenon related to face perception. Nonetheless, we show that compellingly strong Thatcher Effects can be elicited with nonface stimuli, provided that the stimulus set has a familiar standard configuration and a canonical view. Apparently, the Thatcher Illusion is not about faces, and nor is it about Thatcher. It just might, however, be about Britain.
Effect of improving the knowledge, attitude and practice of reproductive health among female migrant workers: a worksite-based intervention in Guangzhou, China
Authors: Gao Xue , Xu Longchang , Lu Ciyong , Wu Jie , Wang Zhijin , Decat Peter , Zhang Wei-Hong , Chen Yimin , Moyer Eileen , Wu Shizhong , Minkauskiene Meile , Van Braeckel Dirk , Temmerman Marleen
Published: December 2014

Background The sexual and reproductive health (SRH) knowledge and attitudes of female migrant workers are far from optimum in China. A worksite-based intervention program on SRH-related knowledge, attitude and practice (SRH KAP) modification may be an effective approach to improve the SRH status among migrant workers. This study aimed to identify better intervention approaches via the implementation and evaluation of two intervention packages. Methods: A worksite-based cluster-randomised intervention study was conducted from June to December 2008 in eight factories in Guangzhou, China. There were 1346 female migrant workers who participated in this study. Factories were randomly allocated to the standard package of interventions group (SPIG) or the intensive package of interventions group (IPIG). Questionnaires were administered to evaluate the effect of two interventions. Results: SRH knowledge scores were higher at follow up than at baseline for all participants of the SPIG; the knowledge scores increased from 6.50 (standard deviation (s.d.) 3.673) to 8.69 (s.d. 4.085), and from 5.98 (s.d. 3.581) to 11.14 (s.d. 3.855) for IPIG; SRH attitude scores increased among unmarried women: the attitude scores changed from 4.25 (s.d. 1.577) to 4.46 (s.d. 1.455) for SPIG, and from 3.99 (s.d. 1.620) to 4.64 (s.d. 1.690) for IPIG; most SRH-related practice was also modified (P < 0.05). In addition, after intervention, the IPIG had a higher knowledge level than the SPIG; the scores were 11.14 (s.d. 3.855) versus 8.69 (s.d. 4.085), and unmarried women in the IPIG had higher condom use rate than the SPIG (86.4% versus 57.1%). Conclusions: The interventions had positive influences on improvements in SRH knowledge, attitudes and behaviours. Additionally, IPIs were more effective than SPIs, indicating that a comprehensive intervention may achieve better results.
The influence of basic beliefs and object-specific attitudes on behavioural intentions towards a rare and little-known amphibian
Authors: Perry-Hill Rebecca , Smith Jordan W. , Reimer Adam , Mase Amber S. , Mullendore Nathan , Mulvaney Kate K. , Prokopy Linda S.
Published: December 2014

Context Given the decline in amphibian populations worldwide, it is essential to build a better understanding of human behaviours that jeopardise their survival. Much of the literature regarding the social–psychological determinants of behaviours related to wildlife has focussed solely on general wildlife beliefs rather than specific attitudes towards a particular species. Aims The goal of this study was to assess how individuals’ behavioural intentions towards a rare and little-known species, the hellbender salamander (Cryptobranchus alleganiensis), are influenced by their attitudes towards the animal and their more general beliefs about wildlife. Methods Questionnaires were distributed to landowners in Missouri (n = 1 065) and Indiana (n = 1 378) in counties where the hellbender is known to exist. A multinomial logit regression model was used to assess the relationship between basic wildlife beliefs, species-specific attitudes and behavioural intentions towards the hellbender. Key results The response rate was 36.6% in Missouri and 41.0% in Indiana. The more value individuals placed on non-hunting wildlife experiences, the less likely they were to say they would engage in a behaviour harmful to the animal (β = –0.47, P = 0.030). The more negative the attitudes towards the hellbender held by individuals, the less likely they were to say they would remove the hook (β = –0.55, P < 0.001), put the animal back (β = –0.77, P < 0.001), or call a resource professional (β = –0.33, P = 0.023). A comparison of the Akaike information criterion (AIC) scores and model log-likelihood values without (AIC = 2 858.36; LLV = –1 395.18) and with (AIC = 2 232.60; LLV = –1 077.30) the species-specific attitude measure showed that its inclusion improved the model. Conclusions Positive attitudes towards the hellbender and mutualistic wildlife beliefs were related to non-detrimental behavioural intentions. However, attitudes towards the animal were found to be a stronger and more consistent predictor of behavioural intentions than basic wildlife beliefs. Implications Efforts to conserve rare or little-known species should focus outreach strategies on developing positive attitudes towards these species, so as to achieve desired changes in behaviour.
Trophic coherence determines food-web stability
Authors: Johnson Samuel , Domínguez-García Virginia , Donetti Luca , Muñoz Miguel A.
Published: December 2014

Significance

The fact that large, complex ecosystems are particularly robust is mysterious in the light of mathematical arguments that suggest they should be unstable; i.e., susceptible to runaway fluctuations in species’ abundances. Here we show that food webs (networks describing who eats whom in an ecosystem) exhibit a property we call trophic coherence, a measure of how neatly the species fall into distinct levels. We find that this property makes networks far more linearly stable than if the links (predator–prey interactions) were placed randomly between species, or according to existing structural models. A simple model we propose to capture this feature shows that networks can, in fact, become more stable with size and complexity, suggesting a possible solution to the paradox.
Miz-1 regulates translation of
Trp53
via ribosomal protein L22 in cells undergoing V(D)J recombination
Authors: Rashkovan Marissa , Vadnais Charles , Ross Julie , Gigoux Mathieu , Suh Woong-Kyung , Gu Wei , Kosan Christian , Möröy Tarik
Published: December 2014

Significance

V(D)J recombination occurs in lymphoid precursors to enable their maturation, but also induces DNA damage. Thus, it has been proposed that the activity of the tumor suppressor and gatekeeper protein p53 must be controlled during this process to prevent premature induction of apoptosis. In this study, we show that the transcription factor Miz-1 can exert such a function. Miz-1 activates expression of the ribosomal protein Rpl22, which in turn controls the translation of p53 specifically in lymphoid precursors. We propose that this Miz-1–Rpl22–p53 pathway prevents p53 from inducing cell death as a response to V(D)J recombination in lymphoid precursors from both the T-lineage and the B-lineage.
Site-specific cation release drives actin filament severing by vertebrate cofilin
Authors: Kang Hyeran , Bradley Michael J. , Cao Wenxiang , Zhou Kaifeng , Grintsevich Elena E. , Michelot Alphée , Sindelar Charles V. , Hochstrasser Mark , De La Cruz Enrique M.
Published: December 2014

Significance

Cofilin is an essential actin regulatory protein that severs filaments, which accelerates network remodeling by increasing the concentration of filament ends available for elongation and subunit exchange. The molecular basis of how cofilin binding interactions fragment filaments, which have stiffness comparable to commercial laboratory plastics, remains a central and unresolved mystery of cellular actin cytoskeleton reorganization. In this study we demonstrate that actin filament severing by vertebrate cofilin is driven by the linked dissociation of a single, site-specific cation that controls filament structure and mechanical properties, and that filament severing is an essential function of cofilin in cells. This work establishes that discrete interactions with cations serve a central regulatory function in mediating actin filament fragmentation by certain classes of severing proteins.
Stoichiometry and geometry of the CXC chemokine receptor 4 complex with CXC ligand 12: Molecular modeling and experimental validation
Authors: Kufareva Irina , Stephens Bryan S. , Holden Lauren G. , Qin Ling , Zhao Chunxia , Kawamura Tetsuya , Abagyan Ruben , Handel Tracy M.
Published: December 2014

Significance

The chemokine receptor axis plays a critical role in numerous physiological and pathological processes, yet the structural basis of receptor interaction with chemokines is poorly understood. Although the community agrees on the existence of two distinct epitopes for recognition of receptors by chemokines, conflicting evidence from structural and mutagenesis studies suggested several possibilities for receptor:chemokine complex stoichiometry. We use a combination of computational, functional, and biophysical approaches to show that despite its dimeric nature, chemokine receptor CXCR4 interacts with its chemokine ligand, CXCL12, in a 1:1 stoichiometry. This result is also likely relevant for other receptor:chemokine pairs. Structural modeling informed by restraints derived from cysteine trapping experiments enabled determination of the receptor:chemokine complex geometry at a medium resolution level.
Nucleosomal promoter variation generates gene expression noise
Authors: Brown Christopher R. , Boeger Hinrich
Published: December 2014

Significance

Transcription is affected, in part, by the spooling of promoter DNA in nucleosomes. EM analysis of single
PHO5
gene molecules from budding yeast revealed a surprising degree of variation in the promoter nucleosome configuration between individual molecules. This variation could be explained on the theory of random transitioning between alternative configurations, suggesting that genes flicker between transcriptionally conducive and unconducive states. What is the origin of this random behavior? Here, we show that the nucleosomal promoter variation cannot be reduced to molecular variation in the gene’s intracellular surroundings, that is, it is intrinsically stochastic and thus, a cause of stochastic transcription rather than its consequence).
van der Waals interactions at the nanoscale: The effects of nonlocality
Authors: Luo Yu , Zhao Rongkuo , Pendry John B.
Published: December 2014

Significance

The van der Waals interaction is a ubiquitous but subtle force between particles mediated by quantum fluctuations of charge. It is the most long-range force acting between particles and influences a range of phenomena such as surface adhesion, friction, and colloid stability. Calculations of the force between parallel surfaces >10 nm apart is a simple task, but when the geometry is more complex, e.g., a pair of nanospheres <5 nm apart, the task is more difficult. Furthermore a macroscopic description of the dielectric properties no longer suffices, and we must consider the diffuse nonlocal nature of the electron polarization cloud. In this paper, we propose a simple analytic treatment of the problem.
Evolution of a plant-specific copper chaperone family for chloroplast copper homeostasis
Authors: Blaby-Haas Crysten E. , Padilla-Benavides Teresita , Stübe Roland , Argüello José M. , Merchant Sabeeha S.
Published: December 2014

Significance

The prevailing dogma is that access to copper (Cu
+
) is restricted to the extent that protein–protein interactions mediate the routing of Cu
+
from transporters in the plasma membrane to target cuproenzymes or transporters within subcellular compartments. The soluble proteins that distribute Cu
+
are called metallochaperones. Although the chloroplast requires Cu
+
, a chaperone that delivers this essential cofactor has remained a missing link in the model for plastid Cu
+
delivery. Using a comparative genomic approach and validating by biochemical characterization, we have discovered a missing chaperone. Uniquely, the previously unidentified chaperone family has evolved from the transporter to which it delivers Cu
+
. We also uncover an interaction between the thylakoid-localized transporter and the Cu
+
chaperone for stromal Cu/Zn superoxide dismutase, which highlights the complexity of Cu
+
distribution networks.
SOXC proteins amplify canonical WNT signaling to secure nonchondrocytic fates in skeletogenesis
Authors: Bhattaram Pallavi , Penzo-Méndez Alfredo , Kato Kenji , Bandyopadhyay Kaustav , Gadi Abhilash , Taketo Makoto M. , Lefebvre Véronique
Published: December 2014

Canonical WNT signaling stabilizes β-catenin to determine cell fate in many processes from development onwards. One of its main roles in skeletogenesis is to antagonize the chondrogenic transcription factor SOX9. We here identify the SOXC proteins as potent amplifiers of this pathway. The SOXC genes, i.e., Sox4, Sox11, and Sox12, are coexpressed in skeletogenic mesenchyme, including presumptive joints and perichondrium, but not in cartilage. Their inactivation in mouse embryo limb bud caused massive cartilage fusions, as joint and perichondrium cells underwent chondrogenesis. SOXC proteins govern these cells cell autonomously. They replace SOX9 in the adenomatous polyposis coli–Axin destruction complex and therein inhibit phosphorylation of β-catenin by GSK3. This inhibition, a crucial, limiting step in canonical WNT signaling, thus becomes a constitutive event. The resulting SOXC/canonical WNT-mediated synergistic stabilization of β-catenin contributes to efficient repression of Sox9 in presumptive joint and perichondrium cells and thereby ensures proper delineation and articulation of skeletal primordia. This synergy may determine cell fate in many processes besides skeletogenesis.
Rescaling principle for isolated essential singularities of quasiregular mappings
Authors: Okuyama Yûsuke , Pankka Pekka
Published: December 2014

We establish a rescaling theorem for isolated essential singularities of quasiregular mappings. As a consequence we show that the class of closed manifolds receiving a quasiregular mapping from a punctured unit ball with an essential singularity at the origin is exactly the class of closed quasiregularly elliptic manifolds, that is, closed manifolds receiving a non-constant quasiregular mapping from a Euclidean space.