bluuebunny/crossref_metadata_2025 huggingface dataset:
Gene structure, regulatory control, and evolution of black widow venom latrotoxins
Authors: Bhere Kanaka Varun , Haney Robert A. , Ayoub Nadia A. , Garb Jessica E.
Published: September 2014

Black widow venom contains α‐latrotoxin, infamous for causing intense pain. Combining 33 kb of Latrodectus hesperus genomic DNA with RNA‐Seq, we characterized the α‐latrotoxin gene and discovered a paralog, 4.5 kb downstream. Both paralogs exhibit venom gland specific transcription, and may be regulated post‐transcriptionally via musashi‐like proteins. A 4 kb intron interrupts the α‐latrotoxin coding sequence, while a 10 kb intron in the 3′ UTR of the paralog may cause non‐sense‐mediated decay. Phylogenetic analysis confirms these divergent latrotoxins diversified through recent tandem gene duplications. Thus, latrotoxin genes have more complex structures, regulatory controls, and sequence diversity than previously proposed.
Identification and comparative analysis of a genomic island in Mycobacterium avium subsp. hominissuis
Authors: Lahiri Annesha , Sanchini Andrea , Semmler Torsten , Schäfer Hubert , Lewin Astrid
Published: September 2014

Mycobacterium avium subsp. hominissuis (MAH) is an environmental bacterium causing opportunistic infections. The objective of this study was to identify flexible genome regions in MAH isolated from different sources. By comparing five complete and draft MAH genomes we identified a genomic island conferring additional flexibility to the MAH genomes. The island was absent in one of the five strains and had sizes between 16.37 and 84.85 kb in the four other strains. The genes present in the islands differed among strains and included phage‐ and plasmid‐derived genes, integrase genes, hypothetical genes, and virulence‐associated genes like mmpL or mce genes.
Potential of novel dextran oligosaccharides as prebiotics for obesity management throughin vitroexperimentation
Authors: Sarbini Shahrul R. , Kolida Sofia , Deaville Eddie R. , Gibson Glenn R. , Rastall Robert A.
Published: September 2014

The energy-salvaging capacity of the gut microbiota from dietary ingredients has been proposed as a contributing factor for the development of obesity. This knowledge generated interest in the use of non-digestible dietary ingredients such as prebiotics to manipulate host energy homeostasis. In the present study, thein vitroresponse of obese human faecal microbiota to novel oligosaccharides was investigated. Dextrans of various molecular weights and degrees of branching were fermented with the faecal microbiota of healthy obese adults in pH-controlled batch cultures. Changes in bacterial populations were monitored using fluorescentin situhybridisation and SCFA concentrations were analysed by HPLC. The rate of gas production and total volume of gas produced were also determined. In general, the novel dextrans and inulin increased the counts of bifidobacteria. Some of the dextrans were able to alter the composition of the obese human microbiota by increasing the counts ofBacteroides–Prevotellaand decreasing those ofFaecalibacterium prausnitziiandRuminococcus bromii/R. flavefaciens. Considerable increases in SCFA concentrations were observed in response to all substrates. Gas production rates were similar during the fermentation of all dextrans, but significantly lower than those during the fermentation of inulin. Lower total gas production and shorter time to attain maximal gas production were observed during the fermentation of the linear 1 kDa dextran than during the fermentation of the other dextrans. The efficacy of bifidobacteria to ferment dextrans relied on the molecular weight and not on the degree of branching. In conclusion, there are no differences in the profiles between the obese and lean human faecal fermentations of dextrans.
The use of energy drinks in sport: perceived ergogenicity and side effects in male and female athletes
Authors: Salinero Juan J. , Lara Beatriz , Abian-Vicen Javier , Gonzalez-Millán Cristina , Areces Francisco , Gallo-Salazar César , Ruiz-Vicente Diana , Del Coso Juan
Published: September 2014

The use of caffeine containing energy drinks has dramatically increased in the last few years, especially in the sport context because of its reported ergogenic effect. The ingestion of low to moderate doses of caffeinated energy drinks has been associated with adverse side effects such as insomnia or increased nervousness. The aim of the present study was to assess psycho-physiological changes and the prevalence of side effects resulting from the ingestion of 3 mg caffeine/kg body mass in the form of an energy drink. In a double-blind and placebo controlled experimental design, ninety experienced and low-caffeine-consuming athletes (fifty-three male and thirty-seven female) in two different sessions were provided with an energy drink that contained 3 mg/kg of caffeine or the same decaffeinated energy drink (placebo; 0 mg/kg). At 60 min after the ingestion of the energy drink, participants completed a training session. The effects of ingestion of these beverages on psycho-physiological variables during exercise and the rate of adverse side effects were measured using questionnaires. The caffeinated energy drink increased self-perceived muscle power during exercise compared with the placebo beverage (6·41 (sd1·7)v.5·66 (sd1·51);P= 0·001). Moreover, the energy drink produced a higher prevalence of side effects such as insomnia (31·2v.10·4 %;P< 0·001), nervousness (13·2v.0 %;P= 0·002) and activeness (16·9v.3·9 %;P= 0·007) than the placebo energy drink. There were no sex differences in the incidence of side effects (P>0·05). The ingestion of an energy drink with 3 mg/kg of caffeine increased the prevalence of side effects. The presence of these side effects was similar between male and female participants.
Factories for Votes? How Authoritarian Leaders Gain Popular Support Using Targeted Industrial Policy
Authors: Hong Ji Yeon , Park Sunkyoung
Published: September 2014

This article explores the link between industrial policy and electoral outcomes under dictatorship. Using a difference-in-differences analysis of county-level panel data from 1971–88 in South Korea, it examines whether the industrial policy implemented by an authoritarian government affects constituents’ electoral decisions. It finds that counties receiving economic benefits through the construction of industrial complexes cast more votes for the incumbent party in subsequent elections. The effects are larger in elections immediately after the appointment of an industrial complex or at the beginning of its construction compared to elections held after the completion of construction. Furthermore, the study tests and rejects reverse causality and migration effects as possible alternative mechanisms for the changes in electoral outcomes. Finally, to understand a unique feature of authoritarian elections, it tests whether industrial complexes affect electoral fraud. Using a genetic matching methodology, it finds that places with new industrial complexes are less likely to experience electoral fraud.
Deviations from Norms and Informed Trading
Authors: Kumar Alok , Page Jeremy K.
Published: September 2014

Investment managers are subject to personal and institutional norms that can constrain their investment choices. We conjecture that norm-constrained investors deviate from such norms only when they have compelling information, and we predict that deviating investments earn relatively high abnormal returns ex post. Consistent with our conjecture, we find that institutions averse to holding lottery-like stocks or sin stocks earn relatively high abnormal returns when they choose to hold such stocks. We find similar but weaker results for deviations from broader style categories. Overall, our evidence indicates that deviations from established institutional or social norms signal informed investing.
Stakeholder prioritization of zoonoses in Japan with analytic hierarchy process method
Authors: KADOHIRA M. , HILL G. , YOSHIZAKI R. , OTA S. , YOSHIKAWA Y.
Published: September 2014

There exists an urgent need to develop iterative risk assessment strategies of zoonotic diseases. The aim of this study is to develop a method of prioritizing 98 zoonoses derived from animal pathogens in Japan and to involve four major groups of stakeholders: researchers, physicians, public health officials, and citizens. We used a combination of risk profiling and analytic hierarchy process (AHP). Profiling risk was accomplished with semi-quantitative analysis of existing public health data. AHP data collection was performed by administering questionnaires to the four stakeholder groups. Results showed that researchers and public health officials focused on case fatality as the chief important factor, while physicians and citizens placed more weight on diagnosis and prevention, respectively. Most of the six top-ranked diseases were similar among all stakeholders. Transmissible spongiform encephalopathy, severe acute respiratory syndrome, and Ebola fever were ranked first, second, and third, respectively.
Risk factors for sporadic Shiga toxin-producingEscherichia coliO157 and non-O157 illness in The Netherlands, 2008–2012, using periodically surveyed controls
Authors: FRIESEMA I. H. M. , SCHOTSBORG M. , HECK M. E. O. C. , VAN PELT W.
Published: September 2014

Shiga toxin-producingEscherichia coli(STEC) infections have been associated with severe illness. Ruminants are seen as the main reservoir and the major transmission route is considered to be foodborne. In The Netherlands, a case-control study was conducted, using data collected during 2008–2012. Patients were interviewed and controls completed a self-administered questionnaire. Patients travelling abroad were excluded from the analyses. STEC O157 and non-O157 were examined separately and differentiated into two age groups (<10 years, ⩾10 years). We included 130 O157 cases, 78 non-O157 cases and 1563 controls. In both age groups of O157 patients, raw spreadable sausage was the main risk factor for infection. For STEC non-O157 cases aged <10 years, contact with farm animals was the main risk factor and in non-O157 cases aged ⩾10 years, consumption of beef was the main risk factor. During 2008–2012, risk factors for STEC infections in the Dutch population differed between age groups and serogroup categories, and were related to eating meat and contact with farm animals. Advising the public about the risks of consuming raw or undercooked meat (products) and hygiene habits in case of contact with farm animals, could help in the prevention of STEC infections.
Re-Emerging Technologies: What's Hot and What's Not!
Authors: Mullan James
Published: September 2014

Three years ago James Mullan delivered a presentation called “Emerging technologies” and followed this up with an article in Legal Information Management (LIM) called “Making mountains out of molehills: a look at some emerging technologies”1 Two years further on and the Editor of LIM asked him to re-visit the issues and to write a follow-up article on the subject. As a result this paper looks at the current state of play with those technologies and identifies some of the significant technological developments to have taken place since his original article.
SLS/BIALL Academic Law Library Survey 2012/2013
Authors: Gee David
Published: September 2014

This is the latest report analysing the results of the Society of Legal Scholars and BIALL Academic Law Library Survey. It has been written by David Gee, Deputy Librarian at the Institute of Advanced Legal Studies, London.
Protein co-translocational unfolding depends on the direction of pulling
Authors: Rodriguez-Larrea David , Bayley Hagan
Published: September 2014

Protein unfolding and translocation through pores occurs during trafficking between organelles, protein degradation and bacterial toxin delivery. In vivo, co-translocational unfolding can be affected by the end of the polypeptide that is threaded into the pore first. Recently, we have shown that co-translocational unfolding can be followed in a model system at the single-molecule level, thereby unravelling molecular steps and their kinetics. Here, we show that the unfolding kinetics of the model substrate thioredoxin, when pulled through an α-haemolysin pore, differ markedly depending on whether the process is initiated from the C terminus or the N terminus. Further, when thioredoxin is pulled from the N terminus, the unfolding pathway bifurcates: some molecules finish unfolding quickly, while others finish ~100 times slower. Our findings have important implications for the understanding of biological unfolding mechanisms and in the application of nanopore technology for the detection of proteins and their modifications.
In vivo fluorescence sensing of the salicylate-induced change of zinc ion concentration in the auditory cortex of rat brain
Authors: Jiang Qin , Guo Zijian , Zhao Yao , Wang Fuyi , Mao Lanqun
Published: September 2014

This study demonstrates a fluorescence method forin vivosensing of the dynamic change of Zn2+concentration in auditory cortex microdialysates induced by salicylate withN′-(7-nitro-2,1,3-benzoxadiazole-4-yl)-N,N,N′-tris(pyridine-2-ylmethyl) ethane-1,2-diamine (NBD-TPEA) as a probe.
MMP9-sensitive polymers mediate environmentally-responsive bivalirudin release and thrombin inhibition
Authors: Chu D. S. , Sellers D. L. , Bocek M. J. , Fischedick A. E. , Horner P. J. , Pun S. H.
Published: September 2014

Enzymatically-responsive bivalirudin polymers loaded in thermoresponsive hydrogels mediate localized therapeutic peptide delivery in spinal cord injuries. These materials respond to upregulated remodelling enzymes to release therapeutic peptide into injured tissue.
Highly efficient iridium-catalyzed asymmetric hydrogenation of β-acylamino nitroolefins
Authors: Yan Qiaozhi , Liu Man , Kong Duanyang , Zi Guofu , Hou Guohua
Published: September 2014

A highly Ir-catalyzed enantioselective hydrogenation of β-acylamino nitroolefins is first reported, which provides straightforward access to chiral β-amino nitroalkanes in excellent enantioselectivities (up to >99.9% ee).
Topotactic elimination of water across a C–C ligand bond in a dense 3-D metal–organic framework
Authors: Yeung Hamish H.-M. , Kosa Monica , Griffin John M. , Grey Clare P. , Major Dan T. , Cheetham Anthony K.
Published: September 2014

Owing to its thermal stability and structural flexibility, the original 3-D framework of lithium l-malate remains intact upon topotactic dehydration.
Silver and magnetic nanoparticles for sensitive DNA detection by SERS
Authors: Donnelly Tara , Smith W. Ewen , Faulds Karen , Graham Duncan
Published: September 2014

The first reported combination of functionalised silver nanoparticles and silver-coated magnetic nanoparticles in a stable sandwich assay for DNA detection using SERS.
C–H/O interactions of nucleic bases with a water molecule: a crystallographic and quantum chemical study
Authors: Veljković D. Ž. , Medaković V. B. , Andrić J. M. , Zarić S. D.
Published: September 2014

The C–H/O interactions of nucleic bases are substantially stronger than the C–H/O interactions of benzene and pyridine. These results can be very important for molecular recognition of DNA and RNA.
Design of nanostructures based on aromatic peptide amphiphiles
Authors: Fleming Scott , Ulijn Rein V.
Published: September 2014

This review examines the structural trends and design rules that underpin the field of aromatic peptide amphiphile assembly.
Record activity and stability of dealloyed bimetallic catalysts for proton exchange membrane fuel cells
Authors: Han Binghong , Carlton Christopher E. , Kongkanand Anusorn , Kukreja Ratandeep S. , Theobald Brian R. , Gan Lin , O'Malley Rachel , Strasser Peter , Wagner Frederick T. , Shao-Horn Yang
Published: September 2014

New Pt–Ni catalysts were made for PEMFCs with previously unachieved ORR activity and device durability that exceed the DOE 2017 targets for commercialization.
One-step synthesis of Ni-doped SnO2 nanospheres with enhanced lithium ion storage performance
Authors: Ye Xiaomin , Zhang Wenjing , Liu Qianjin , Wang Shuping , Yang Yanzhao , Wei Huiying
Published: September 2014

Ni-doped SnO2 nanospheres were prepared and exhibited excellent cycle performance and capacity retention.
Novel room-temperature thermotropic liquid crystals: synthesis and mesomorphism of gallic–perylene–gallic trimers
Authors: Meng Li , Wu Qiumei , Yang Fafu , Guo Hongyu
Published: September 2014

Compounds 7 and 8 with soft bridging chains exhibit columnar mesophase, but compound 9 with a rigid chain exhibits no mesophase.
The journey ofl-tartaric acid in the world of enantiomerically pure bis- and trisadducts of C60with the inherently chiral trans-3 and all-trans-3 addition patterns
Authors: Chronakis Nikos
Published: September 2014

The journey ofl-tartaric acid through its derivative (−)-dimethyl-2,3-O-isopropylidene-l-tartrate in the synthesis of enantiomerically pure diols,cyclo-[n]-malonates and finally, inherently chiraltrans-3 bisadducts and all-trans-3 trisadducts of C60is presented.
Preparation of lepidocrocites with different degrees of crystallization and their photocatalytic properties
Authors: Chen Rufen , Zhao Shuangfei , Meng Xiangmin , Liu Hui , Wei Yu
Published: September 2014

Lepidocrocites with different degrees of crystallization were obtained, and the low-crystalline lepidocrocite showed higher adsorption and photocatalytic activity.
Synthesis of chiral core based triazole dendrimers with m-terphenyl surface unit and their antibacterial studies
Authors: Thirunarayanan Ayyavu , Raja Sebastian , Mohanraj Gunasekaran , Rajakumar Perumal
Published: September 2014

Antibacterial activity against Shigella dysenteriae, Staphylococcus aureus and Serratia marcescen was studied with S-BINOL based triazole dendrimers 1, 2 and 3 with m-terphenyl surface units. Supported by molecular docking studies, the activity dendrimer 2 was comparable to that of streptomycin.
Controlling the hydrothermal growth and the properties of ZnO nanorod arrays by pre-treating the seed layer
Authors: Yin Y. , Sun Y. , Yu M. , Liu X. , Yang B. , Liu D. , Liu S. , Cao W. , Ashfold M. N. R.
Published: September 2014

Annealing or plasma pre-treating the ZnO seed layer influences the nucleation and hydrothermal growth of ZnO nanorods and their photoluminescence.
Vanadium doping of strontium germanate and their visible photocatalytic properties
Authors: Pei L. Z. , Wang S. , Lin N. , Liu H. D. , Guo Y. H.
Published: September 2014

Strontium germanate microrods have been doped by vanadium exhibiting good photocatalytic degradation of methylene blue under sunlight irradiation.
A convenient method for producing mono- and dichlorohydrins from glycerol
Authors: Giomi Donatella , Malavolti Marino , Piccolo Oreste , Salvini Antonella , Brandi Alberto
Published: September 2014

The selective transformation of glycerol into mono- and dichlorohydrins was performed with trimethylchlorosilane as chlorinating agent and acetic acid as catalyst.
One dimensional CdS/ZnO nanocomposites: an efficient photocatalyst for hydrogen generation
Authors: Vaishnav Jamuna K. , Arbuj Sudhir S. , Rane Sunit B. , Amalnerkar Dinesh P.
Published: September 2014

One-dimensional ZnO nanostructures were synthesized using solvothermal reaction method, and in situ CdS nanoparticles were grown on 1D ZnO having different CdS compositions such as 0.1, 0.5, 1 and 5 mol% using microwave reaction system.
Synthesis, characterization, and computational study of potential itaconimide-based initiators for atom transfer radical polymerization
Authors: Deoghare Chetana , Baby C. , Nadkarni Vishnu S. , Behera Raghu Nath , Chauhan Rashmi
Published: September 2014

We report synthesis of potential initiators1a-Br,2a-Br, and3a-Br for the ATRP ofN-phenylitaconimide and MMA. We find (i) good agreement between experimentally determined and calculatedKATRPvalues (ii)3a-Br performs better than the commercially available initiator.
Enantioselective construction of C-chiral allylic sulfilimines via the iridium-catalyzed allylic amination with S,S-diphenylsulfilimine: asymmetric synthesis of primary allylic amines
Authors: Grange Rebecca L. , Clizbe Elizabeth A. , Counsell Emma J. , Evans P. Andrew
Published: September 2014

We have devised a highly regio- and enantioselective iridium-catalyzed allylic amination reaction with the sulfur-stabilized aza-ylide, S,S-diphenylsulfilimine.
Decoupled ion conduction in poly(2-acrylamido-2-methyl-1-propane-sulfonic acid) homopolymers
Authors: Noor Siti Aminah Mohd , Sun Jiazeng , MacFarlane Douglas R. , Armand Michel , Gunzelmann Daniel , Forsyth Maria
Published: September 2014

A family of novel sulfonate based homopolymers has been prepared by partially replacing sodium cations with different types of ionic liquid ammonium counter-cations, leading to an increased degree of decoupling of the conductivity from the glass transition of the ionomers.
The role and therapeutic potential of the autotaxin–lysophosphatidate signalling axis in breast cancer
Authors: Teo Katy , Brunton Valerie G.
Published: September 2014

ATX (autotaxin) is a secreted lysophospholipase capable of catalysing the formation of the bioactive lipid mediator LPA (lysophosphatidate) from LPC (lysophosphatidylcholine). The ATX–LPA signalling axis plays an important role in both normal physiology and disease pathogenesis, including cancer. In a number of different human cancers, expression of ATX and the G-protein-coupled LPARs (lysophosphatidic acid receptors) have been shown to be elevated and their activation regulates many processes central to tumorigenesis, including proliferation, invasion, migration and angiogenesis. The present review provides an overview of the ATX–LPA signalling axis and collates current knowledge regarding its specific role in breast cancer. The potential manipulation of this pathway to facilitate diagnosis and treatment is also discussed.
13 mW 80 GHz down‐conversion mixer with 1.5 dB gain and 49.2 dB LO–RF isolation
Authors: Lin Y.S. , Li G.H.
Published: September 2014

An 80 GHz double‐balanced down‐conversion mixer for automotive radars using standard 90 nm complementary metal oxide semiconductor (CMOS) technology is reported. The mixer comprises a double‐balanced Gilbert cell with inductive source‐degeneration radio‐frequency (RF) transconductance stage for wideband RF‐port input impedance matching and conversion gain (CG) enhancement, a Marchand balun for converting the single RF input signal to differential signal, a Marchand balun for converting the single local oscillator (LO) input signal to differential signal and a baseband amplifier. The mixer consumes 13 mW and achieves excellent RF‐port input reflection coefficient of −13.1 ∼ −19.4 dB and LO‐port input reflection coefficient of −9.1 ∼ −11.8 dB for frequencies in the range 75–85 GHz. In addition, for frequencies of 75–85 GHz, the mixer achieves CG of −1 ∼1.5 dB, LO–RF isolation of 43.5–49.2 dB and LO–intermediate frequency (IF) isolation of 56.5–64.5 dB, one of the best CG and port‐to‐port isolation results ever reported for a CMOS down‐conversion mixer with operation frequency about 80 GHz.
InGaZnO metal‐base transistor with high current gain
Authors: Huang H.Y. , Wang S.J. , Hung C.H. , Wu C.H. , Lin W.C.
Published: September 2014

The fabrication of metal‐base transistors (MBTs) based on InGaZnO at room temperature is reported for the first time. With a suitable oxygen doping to the sputtering‐deposited InGaZnO film and an HfSiO interlayer, improved diode performances with enhanced Schottky barrier heights of 0.70 and 0.66 eV are obtained for the base/collector (Ti/InGaZnO) and base/emitter (Au/HfSiO/InGaZnO) junctions, respectively. InGaZnO MBT using a Ti(10 nm)/Au(10 m)/HfSiO(5 nm) dual metal base shows a high common‐emitter current gain (β) 840–310 at VCE = 2 V and IB ranging from 1 to 10 nA.
Exact analysis of downlink capacity employing opportunistic feedback and maximal ratio transmission in Rayleigh fading environments
Authors: Le Khoa N. , Huang David
Published: September 2014

The downlink throughput of opportunistic‐feedback multiuser wireless systems with capture effects employing maximal ratio transmission (MRT) in a Rayleigh fading environment is studied. To the best of the authors’ knowledge, MRT has not been employed to improve multiuser system throughput with capture effects. Employing MRT means that the channel fading gains between the base station (BS) and users are a chi‐square distribution with 2L degrees of freedom, where L is the diversity order, as opposed to Rayleigh distribution which has been examined in detail in the literature. Thus, the main challenge is to obtain a new and compact channel capacity expression for the system in which the roles of BS and users are reversed to make it practically sound. The new downlink throughput expression is derived as a function of L, fading‐gain threshold η, capture ratio z and other parameters. For large η, the capture effects are not as effective as when η is small. Effects of the capture ratio z on system throughput are also obtained. The new findings are validated using available results in the open literature.
Eavesdropping near‐field contactless payments: a quantitative analysis
Authors: Diakos Thomas P. , Briffa Johann A. , Brown Tim W. C. , Wesemeyer Stephan
Published: September 2014

This paper presents an assessment of how successful an eavesdropping attack on a contactless payment transaction can be in terms of bit and frame error rates, using an easily concealable antenna and low‐cost electronics. Potential success of an eavesdropping attack largely depends on the correct recovery of the data frames used in the ISO 14443 standard. A near‐field communication inductive loop antenna was used to emulate an ISO 14443 transmission. For eavesdropping, an identical inductive loop antenna as well as a shopping trolley modified to act like an antenna were used. The authors present and analyse frame error rates obtained with the authors equipment over a range of distances, up to 100 cm, well above the official maximum operating distance depending on the magnetic field strength.
Edge adaptive directional total variation
Authors: Zhang Hua , Wang Yuanquan
Published: September 2014

The directional total variation (DTV) model has been proposed very recently for image denoising. However, the DTV model works well when there is just one dominant direction in the image. In this Letter, the authors propose to make the DTV model adaptive to image edge direction so that the proposed model can handle images with several dominant directions. Experiment and comparison show the effectiveness of the proposed method.
Complex‐valued interferometric inverse synthetic aperture radar image compression base on compressed sensing
Authors: Li Liechen , Li Daojing , Liu Bo , Zhang Qingjuan
Published: September 2014

Complex‐valued interferometric inverse synthetic aperture radar (InISAR) image compression is discussed in this study. The target scene has its continuity and is compressible. However, because of the random phase of each resolution cell, the frequency spectrum of an ISAR image is wide and the complex‐valued image is hard to compress. A complex‐valued ISAR image compression approach is proposed. Using two or more antennas and interferometry processing, the random phase of image pixel can be cancelled and the frequency spectrum becomes sparse. Therefore the theory of compressed sensing can be introduced to the process of the complex‐valued image compression. Hence, the complex‐valued InISAR image compression and reconstruction can be completed. Results on real data are presented to validate the method. In comparison with results of the conventional compression techniques, the proposed method shows the better ability to preserve both the imaging magnitude and interferometric phase.
Time‐varying block codes for synchronisation errors: maximum a posteriori decoder and practical issues
Authors: Briffa Johann A. , Buttigieg Victor , Wesemeyer Stephan
Published: September 2014

In this study, the authors consider time‐varying block (TVB) codes, which generalise a number of previous synchronisation error‐correcting codes. They also consider various practical issues related to maximum a posteriori (MAP) decoding of these codes. Specifically, they give an expression for the expected distribution of drift between transmitter and receiver because of synchronisation errors. They determine an appropriate choice for state space limits based on the drift probability distribution. In turn, they obtain an expression for the decoder complexity under given channel conditions in terms of the state space limits used. For a given state space, they also give a number of optimisations that reduce the algorithm complexity with no further loss of decoder performance. They also show how the MAP decoder can be used in the absence of known frame boundaries, and demonstrate that an appropriate choice of decoder parameters allows the decoder to approach the performance when frame boundaries are known, at the expense of some increase in complexity. Finally, they express some existing constructions as TVB codes, comparing performance with published results and showing that improved performance is possible by taking advantage of the flexibility of TVB codes.
Gyrokinetic modelling of stationary electron and impurity profiles in tokamaks
Authors: Skyman A. , Tegnered D. , Nordman H. , Strand P.
Published: September 2014

Particle transport due to Ion Temperature Gradient (ITG)/Trapped Electron Mode (TEM) turbulence is investigated using the gyrokinetic code GENE. Both a reduced quasilinear treatment and nonlinear simulations are performed for typical tokamak parameters corresponding to ITG dominated turbulence. The gyrokinetic results are compared and contrasted with results from a computationally efficient fluid model. A selfconsistent treatment is used, where the stationary local profiles are calculated corresponding to zero particle flux simultaneously for electrons and trace impurities. The scaling of the stationary profiles with magnetic shear, safety factor, electron-to-ion temperature ratio, collisionality, toroidal sheared rotation, plasma β, triangularity, and elongation is investigated. In addition, the effect of different main ion mass on the zero flux condition is discussed. The electron density gradient can significantly affect the stationary impurity profile scaling. It is therefore expected that a selfconsistent treatment will yield results more comparable to experimental results for parameter scans where the stationary background density profile is sensitive. This is shown to be the case in scans over magnetic shear, collisionality, elongation, and temperature ratio, for which the simultaneous zero flux electron and impurity profiles are calculated. A slight asymmetry between hydrogen, deuterium, and tritium with respect to profile peaking is obtained, in particular, for scans in collisionality and temperature ratio.
Local-heterogeneous responses and transient dynamics of cage breaking and formation in colloidal fluids
Authors: Nag Preetom , Teramoto Hiroshi , Li Chun-Biu , Terdik Joseph Z. , Scherer Norbert F. , Komatsuzaki Tamiki
Published: September 2014

Quantifying the interactions in dense colloidal fluids requires a properly designed order parameter. We present a modified bond-orientational order parameter, \documentclass[12pt]{minimal}\begin{document}$\bar{\psi }_{6}$\end{document}ψ¯6, to avoid problems of the original definition of bond-orientational order parameter. The original bond-orientational order parameter can change discontinuously in time but our modified order parameter is free from the discontinuity and, thus, it is a suitable measure to quantify the dynamics of the bond-orientational ordering of the local surroundings. Here we analyze \documentclass[12pt]{minimal}\begin{document}$\bar{\psi }_{6}$\end{document}ψ¯6 in a dense driven monodisperse quasi-two-dimensional colloidal fluids where a single particle is optically trapped at the center. The perturbation by the trapped and driven particle alters the structure and dynamics of the neighboring particles. This perturbation disturbs the flow and causes spatial and temporal distortion of the bond-orientational configuration surrounding each particle. We investigate spatio-temporal behavior of \documentclass[12pt]{minimal}\begin{document}$\bar{\psi }_{6}$\end{document}ψ¯6 by a Wavelet transform that provides a time-frequency representation of the time series of \documentclass[12pt]{minimal}\begin{document}$\bar{\psi }_{6}$\end{document}ψ¯6. It is found that particles that have high power in frequencies corresponding to the inverse of the timescale of perturbation undergo distortions of their packing configurations that result in cage breaking and formation dynamics. To gain insight into the dynamic structure of cage breaking and formation of bond-orientational ordering, we compare the cage breaking and formation dynamics with the underlying dynamical structure identified by Lagrangian Coherent Structures (LCSs) estimated from the finite-time Lyapunov exponent (FTLE) field. The LCSs are moving separatrices that effectively divide the flow into distinct regions with different dynamical behavior. It is shown that the spatial distribution of the FTLE field and the power of particles in the wavelet transform have positive correlation, implying that LCSs provide a dynamic structure that dominates the dynamics of cage breaking and formation of the colloidal fluids.
On the full exploitation of symmetry in periodic (as well as molecular) self-consistent-field ab initio calculations
Authors: Orlando Roberto , De La Pierre Marco , Zicovich-Wilson Claudio M. , Erba Alessandro , Dovesi Roberto
Published: September 2014

Use of symmetry can dramatically reduce the computational cost (running time and memory allocation) of self-consistent-field ab initio calculations for molecular and crystalline systems. Crucial for running time is symmetry exploitation in the evaluation of one- and two-electron integrals, diagonalization of the Fock matrix at selected points in reciprocal space, reconstruction of the density matrix. As regards memory allocation, full square matrices (overlap, Fock, and density) in the Atomic Orbital (AO) basis are avoided and a direct transformation from the packed AO to the symmetry adapted crystalline orbital basis is performed, so that the largest matrix to be handled has the size of the largest sub-block in the latter basis. Quantitative examples, referring to the implementation in the CRYSTAL code, are given for high symmetry families of compounds such as carbon fullerenes and nanotubes.
A physical model of radiated enhancement of plasma-surrounded antenna
Authors: Gao Xiaotian , Wang Chunsheng , Jiang Binhao , Zhang Zhonglin
Published: September 2014

A phenomenon that the radiated power may be enhanced when an antenna is surrounded by a finite plasma shell has been found in numerical and experimental studies. In this paper, a physical model was built to express the mechanism of the radiated enhancement. In this model, the plasma shell is treated as a parallel connection of a capacitance and a conductance whose parameters change with the system parameters (plasma density, collision frequency, and antenna frequency). So, the radiated enhancement can be explained by the resonance between the plasma shell and the infinite free space. Furthermore, the effects of system parameters on the radiated power are given and effects corresponding to mechanisms are performed based on the physical model.
Optimisation of the material properties of indium tin oxide layers for use in organic photovoltaics
Authors: Doggart P. , Bristow N. , Kettle J.
Published: September 2014

The influence of indium tin oxide [(In2O3:Sn), ITO] material properties on the output performance of organic photovoltaic (OPV) devices has been modelled and investigated. In particular, the effect of altering carrier concentration (n), thickness (t), and mobility (μe) in ITO films and their impact on the optical performance, parasitic resistances and overall efficiency in OPVs was studied. This enables optimal values of these parameters to be calculated for solar cells made with P3HT:PC61BM and PCPDTBT:PC71BM active layers. The optimal values of n, t and μe are not constant between different OPV active layers and depend on the absorption spectrum of the underlying active layer material system. Consequently, design rules for these optimal values as a function of donor bandgap in bulk-heterojunction active layers have been formulated.
The effect of exceptionally high fluorine doping on the anisotropy of single crystalline SmFeAsO1−xFx
Authors: Fujioka Masaya , Denholme Saleem J. , Tanaka Masashi , Takeya Hiroyuki , Yamaguchi Takahide , Takano Yoshihiko
Published: September 2014

We prepared single crystalline SmFeAsO1−xFx with an exceptionally high fluorine concentration by using a CsCl flux method. Comparing to conventional flux methods, this method can introduce about double the amount of fluorine into the oxygen site. The obtained single crystal shows the highest superconducting transition temperature (Tc = 57.5 K) in single crystalline iron pnictides. In addition, the residual resistivity ratio is almost three times as large as that of previously reported single crystals. This suggests that our single crystals are suitable for investigation of the intrinsic superconducting properties, since they have few defects and impurities. Using both the Werthamer-Helfand-Hohenberg model and the effective mass model, we demonstrated that a higher fluorine concentration suppresses the anisotropic superconductivity of SmFeAsO1−xFx.
Towards ultra-stiff materials: Surface effects on nanoporous materials
Authors: Lu Dingjie , Xie Yi Min , Li Qing , Huang Xiaodong , Zhou Shiwei
Published: September 2014

The significant rise in the strength and stiffness of porous materials at nanoscale cannot be described by conventional scaling laws. This letter investigates the effective Young's modulus of such materials by taking into account surface effect in a microcellular architecture designed for an ultralight material whose stiffness is an order of magnitude higher than most porous materials. We find that by considering the surface effects the predicted stiffness using Euler-Bernoulli beam theory compares well to experimental data for spongelike nanoporous gold with random microstructures. Analytical results show that, of the two factors influencing the effective Young's modulus, the residual stress is more important than the surface stiffness.
Optical spin-to-orbital angular momentum conversion in ultra-thin metasurfaces with arbitrary topological charges
Authors: Bouchard Frédéric , De Leon Israel , Schulz Sebastian A. , Upham Jeremy , Karimi Ebrahim , Boyd Robert W.
Published: September 2014

Orbital angular momentum associated with the helical phase-front of optical beams provides an unbounded “space” for both classical and quantum communications. Among the different approaches to generate and manipulate orbital angular momentum states of light, coupling between spin and orbital angular momentum allows a faster manipulation of orbital angular momentum states because it depends on manipulating the polarisation state of light, which is simpler and generally faster than manipulating conventional orbital angular momentum generators. In this work, we design and fabricate an ultra-thin spin-to-orbital angular momentum converter, based on plasmonic nano-antennas and operating in the visible wavelength range that is capable of converting spin to an arbitrary value of orbital angular momentum ℓ. The nano-antennas are arranged in an array with a well-defined geometry in the transverse plane of the beam, possessing a specific integer or half-integer topological charge q. When a circularly polarised light beam traverses this metasurface, the output beam polarisation switches handedness and the orbital angular momentum changes in value by ℓ=±2qℏ per photon. We experimentally demonstrate ℓ values ranging from ±1 to ±25 with conversion efficiencies of 8.6% ± 0.4%. Our ultra-thin devices are integratable and thus suitable for applications in quantum communications, quantum computations, and nano-scale sensing.
Perpendicular magnetic anisotropy in Ta|Co40Fe40B20|MgAl2O4 structures and perpendicular CoFeB|MgAl2O4|CoFeB magnetic tunnel junction
Authors: Tao B. S. , Li D. L. , Yuan Z. H. , Liu H. F. , Ali S. S. , Feng J. F. , Wei H. X. , Han X. F. , Liu Y. , Zhao Y. G. , Zhang Q. , Guo Z. B. , Zhang X. X.
Published: September 2014

Magnetic properties of Co40Fe40B20 (CoFeB) thin films sandwiched between Ta and MgAl2O4 layers have been systematically studied. For as-grown state, Ta/CoFeB/MgAl2O4 structures exhibit good perpendicular magnetic anisotropy (PMA) with interface anisotropy Ki = 1.22 erg/cm2, which further increases to 1.30 erg/cm2 after annealing, while MgAl2O4/CoFeB/Ta multilayer shows in-plane magnetic anisotropy and must be annealed in order to achieve PMA. For bottom CoFeB layer, the thickness window for PMA is from 0.6 to 1.0 nm, while that for top CoFeB layer is between 0.8 and 1.4 nm. Perpendicular magnetic tunnel junctions (p-MTJs) with a core structure of CoFeB/MgAl2O4/CoFeB have also been fabricated and tunneling magnetoresistance ratio of about 36% at room temperature and 63% at low temperature have been obtained. The intrinsic excitations in the p-MTJs have been identified by inelastic electron-tunneling spectroscopy.
Dual-frequency terahertz emission from splitting filaments induced by lens tilting in air
Authors: Zhang Zhelin , Chen Yanping , Yang Liu , Yuan Xiaohui , Liu Feng , Chen Min , Xu Jianqiu , Sheng Zhengming , Zhang Jie
Published: September 2014

Dual-frequency terahertz radiation from air-plasma filaments produced with two-color lasers in air has been demonstrated experimentally. When a focusing lens is tilted for a few degrees, it is shown that the laser filament evolves from a single one to two sub-filaments. Two independent terahertz sources emitted from the sub-filaments with different frequencies and polarizations are identified, where the frequency of terahertz waves from the trailing sub-filament is higher than that from the leading sub-filament.
Low thermal conductivity and triaxial phononic anisotropy of SnSe
Authors: Carrete Jesús , Mingo Natalio , Curtarolo Stefano
Published: September 2014

In this theoretical study, we investigate the origins of the very low thermal conductivity of tin selenide (SnSe) using ab-initio calculations. We obtained high-temperature lattice thermal conductivity values that are close to those of amorphous compounds. We also found a strong anisotropy between the three crystallographic axes: one of the in-plane directions conducts heat much more easily than the other. Our results are compatible with most of the experimental literature on SnSe and differ markedly from the more isotropic values reported by a recent study.
Stacking fault induced tunnel barrier in platelet graphite nanofiber
Authors: Lan Yann-Wen , Chang Wen-Hao , Li Yuan-Yao , Chang Yuan-Chih , Chang Chia-Seng , Chen Chii-Dong
Published: September 2014

A correlation study using image inspection and electrical characterization of platelet graphite nanofiber devices is conducted. Close transmission electron microscopy and diffraction pattern inspection reveal layers with inflection angles appearing in otherwise perfectly stacked graphene platelets, separating nanofibers into two domains. Electrical measurement gives a stability diagram consisting of alternating small-large Coulomb blockade diamonds, suggesting that there are two charging islands coupled together through a tunnel junction. Based on these two findings, we propose that a stacking fault can behave as a tunnel barrier for conducting electrons and is responsible for the observed double-island single electron transistor characteristics.
Population Structure and Dynamics since 1949
Authors: Scharping Thomas
Published: September 2014

Studies of population dynamics are the domain of demography, a joint enterprise of social and biological sciences that, since its beginnings in the 17th century, has developed into a highly mathematized subject. Statistics and precision are essential in the field, especially in the Chinese case, where minuscule discrepancies of rates translate into huge differences in absolute amounts, with widely differing per capita indicators for one-fifth of the world population following. At its best, demography offers empirical substance, methodological stringency, and representative findings that are often missing in the more freewheeling contributions of other disciplines; at its worst, it becomes immersed in mechanical number-crunching in which the social and cultural, and political and economic, meaning of data evaporates. In China, population has been a topic for rulers, bureaucrats, and philosophers of statecraft for nearly three thousand years. As a modern discipline, however, demography had to await importation from the West in 1918. During the Mao era it first became a forbidden bourgeois subject, then made a brief comeback in the mid-1950s, was banned again until 1973, and existed in the shadows up to 1977. Population figures and other statistical data were nonexistent or inaccessible after the Great Leap Forward of 1958–1960. When they became available again, the leadership’s alarm over high population numbers led to tightened birth policies and turned demography from a proscribed into a prescribed subject. Because of the crucial importance of demographic information for public policy and development planning in post-Mao China, population studies has evolved into a key discipline of Chinese social sciences. Since the 1980s there has been an unprecedented growth of such studies, and the mass of statistics and research dwarfs information from other parts of the world. At the same time, their academic standards have been raised to international levels. These developments have revived Western studies on Chinese population dynamics, which were languishing for a long time. Since China’s 1982 census, studies on the three main components of demographic change—mortality, fertility and migration—and on related topics, have thrived. Most survey-based investigations, analyses, and concomitant debates have appeared in demographic publications, but less so in Chinese Studies. Work focuses on the analysis of population size and composition, growth dynamics, and data relationships. Fruitful extensions follow, once deeper questions of cause and effect are raised. Population studies then become linked to both Chinese Studies and disciplines such as sociology, economics and political science, anthropology, history, and geography, which provide indispensable interpretative background. However, the complex interdependencies in population development have notoriously resisted theoretical generalization.
Effect of Holder Pasteurisation on Human Milk Glycosaminoglycans
Authors: Coscia Alessandra , Peila Chiara , Bertino Enrico , Coppa Giovanni V. , Moro Guido E. , Gabrielli Orazio , Zampini Lucia , Galeazzi Tiziana , Maccari Francesca , Volpi Nicola
Published: September 2014

Objectives:

The benefits of human milk for preterm infants are mainly the result of its nutritional characteristics and the presence of biologically active compounds. Among these compounds, glycosaminoglycans (GAGs) play an emerging leading role. When mother's milk is unavailable or in short supply, pasteurised donor milk represents an important nutritional alternative. The aim of this study was to evaluate the effect of Holder pasteurisation on the concentration of different GAGs in preterm human milk.

Methods:

Milk samples collected from 9 mothers having delivered preterm were divided into 2 parts. One part of each sample was immediately frozen (−80°C), whereas the other part was pasteurised with the Holder method before being frozen at −80°C. Specific analytical procedures were applied to evaluate the amount, composition, and structure of main human milk GAGs.

Results:

No significative differences were measured between not‐treated and pasteurised samples for total GAGs content, relative percentages of chondroitin sulfate and heparan sulfate, and main parameters related to galactosaminoglycans structure, even if a slight decrease of total GAGs content of ∼18% was observed in treated samples.

Conclusions:

Our results indicate that the Holder pasteurisation does not significatively affect the concentration of the main human milk GAGs.