bluuebunny/crossref_metadata_2025 huggingface dataset:
Adiponectin is released via a unique regulated exocytosis pathway from a pre-formed vesicle pool on insulin stimulation
Authors: Lim Chun-Yan , Hong Wanjin , Han Weiping
Published: September 2015

Adiponectin, a hormone secreted from adipocytes and released at a high rate into the circulation, plays a pivotal role in maintaining insulin sensitivity at the whole-body level. Despite the importance of this adipokine in metabolic homoeostasis, the mechanism of its secretion from adipocytes remains largely unclear. In the present study, we investigated the subcellular localization of adiponectin, and its secretion regulation in 3T3-L1-differentiated adipocytes, using biochemical methods and fluorescence microscopic imaging. We show that adiponectin is localized in vesicular compartments with no apparent overlap with the Golgi apparatus or endosomes. Moreover, adiponectin-containing vesicles are enriched in two distinct pools: one at the plasma membrane (PM) and the other co-fractionating with endoplasmic reticulum membranes. When viewed under a total internal refection fluorescence microscope, a subset of adiponectin-Venus vesicles is readily observed in proximity to PMs, and could be released in response to insulin. Insulin-stimulated adiponectin release appears to be from a pre-existing pool of vesicles, and is not dependent on new protein synthesis, because adiponectin mRNA levels remain unchanged over a 6-h period of insulin treatment, and inhibition of protein synthesis has no effect on adiponectin release. Disruption of insulin signalling by inhibitors of phosphoinositide 3-kinase and protein kinase B (Akt)-1/2 abrogates the stimulated release of adiponectin. Taken together, our results show that adiponectin is stored in a unique vesicular compartment, and released through a regulated exocytosis pathway that is dependent on insulin signalling.
Dual‐band frequency selective surfaces based on multi‐arm sub‐wavelength Archimedean spirals
Authors: Kelley M. , Huff G.
Published: September 2015

Two design strategies are presented to create dual‐band frequency selective surfaces based on multi‐arm Archimedean spirals. A single‐band element is first presented as the basis for the surface. The individual arm lengths of the spirals are utilised as the primary design parameter to synthesise the passband and stopband responses. The first approach uses a lattice of four‐arm spirals with alternating sizes, and the second combines these into an eight‐arm uniform lattice of elements. Measured and simulated results are included for a fabricated S‐band prototype of each topology to demonstrate the basic design strategies.
Ambiguity function and Cramer‐Rao bounds for standard and new modified Costas signals
Authors: Touati N. , Tatkeu C. , Chonavel T. , Elhillali Y. , Rivenq A.
Published: September 2015

The Cramer‐Rao bound (CRB) gives a lower variance bound that an estimator can achieve. Presented is a mathematical approach to estimate it for specific radar signals, namely Costas signals and their modified versions. The modified versions design consists in widening Costas frequency hops and replacing rectangular pulses with other waveforms (namely linear frequency modulated pulses, phase codes and other Costas codes). The calculation is based on approximations of the ambiguity function (AF) around the mainlobe. The CRBs are then derived based on relationships between the AF and these bounds.
Block‐flow noise power estimation algorithm for pulsed interference detection of GNSS receivers
Authors: Huo Shumin , Nie Junwei , Wang Feixue
Published: September 2015

The noise power estimation for pulsed interference detection in global navigation satellite system (GNSS) receivers is considered. Previous effective consecutive mean excision (CME) related algorithms in this area work in an inter‐block iterative fashion and the convergent process is usually quite time‐consuming and needs a large storage space. A block‐flow manner based on the backward CME (BCME) algorithm to overcome these problems is proposed. Numerical results show that the method decreases the computation and storage requirements of BCME, and possesses closer convergence properties.
Illumination compensation method using edge‐weakening guided image filter for face recognition
Authors: Chen Chao , Shen Haibin
Published: September 2015

In face recognition, the self‐quotient image (SQI) is a widely used preprocessing step to compensate for illumination. To improve SQI performance, a specially designed edge‐weakening guided image filter (EWGIF) is proposed. An edge aware coefficient in the EWGIF makes it aware of edges and able to change the smoothing level automatically according to the image contents. Through the improved SQI, most of the face informatic areas are well preserved, while inconsequential parts are dropped. Experimental results on the extended Yale B and the Gray FERET databases show that face recognition accuracy is significantly improved with the EWGIF.
Low‐complexity leakage current acquisition system for transmission line insulators employing GSM voice channel
Authors: Ghosh R. , Chatterjee B. , Dey D. , Chakravorti S.
Published: September 2015

With the rapid advancements in electronics and in communication infrastructures, the deployment of low‐complexity devices for power system monitoring has become an active area of research. For the large‐scale deployment of monitoring devices, robust and economical remote data acquisition systems for power system monitoring are required. Keeping this in mind, the scheme of a remote leakage current acquisition system for high‐voltage insulators that may be employed for remote monitoring purposes is described. A low‐complexity method is adopted for the extraction of harmonic information from the leakage current signal. Unlike existing remote insulator‐monitoring techniques that employ a dedicated fibre‐optic network and satellite communication, the mobile communication voice channel is used to communicate the data to a central location for analysis. This provides an economical solution for the remote monitoring of insulators that may be used for large‐scale deployment.
Generating simple‐to‐apply comprehensive engineering recommendation for earthing safety in systems with solidly earthed neutral
Authors: Radakovic Zoran , Paunovic Nikola , Milosevic Vladimir , Jovanovic Milos
Published: September 2015

This study presents the procedure of generating simple‐to‐apply engineering recommendation for earthing systems and boundaries for setting of earth faults relay protection in power systems with solidly earthed neutral. The simple rules are based on ‘the worst case analyses’. Motivation for this work was simplification of the engineering process with acceptable deviation from economic optimum. Another reason is addressing the specific problems occurring in studied arid desert terrains conditions, which are described in this study. The analyses are based on calculation of earth fault current, its distribution over multiple earthing systems along the power line connected via protective conductor, tripping time dependent on relay curve, and allowed step and touch voltages depending on tripping time and characteristics of soil and optional additional surface material. For these calculations, the Excel/VBA software tool is developed and used. Different topologies of earthing systems (with grounding contours, rods, with/without backfill materials, etc.) considering layout of equipment in substation are studied using finite‐elements software in order to determine the ratio of touch and step voltages to ground potential rise – GPR. The methodology is explained through a prominent case study of overhead line with overhead ground wire and metallic poles in the rural area.
Compacting and partitioning‐based simulation solution for frequency‐dependent network equivalents in real‐time digital simulator
Authors: Hu Yizhong , Wu Wenchuan , Zhang Boming
Published: September 2015

Rational models of frequency‐dependent network equivalents (FDNEs) have been used in real‐time digital simulator (RTDS) for power‐system simulation. However, this can lead to a computational burden issue; the application of FDNEs may result in a loss of real‐time simulation features because the computational cost of the FDNE component exceeds the limits of RTDS. The authors describe a solution that combines compacting and partitioning of the FDNEs, whereby the former reduces the redundancy in the mathematical model and the latter allows us to exploit parallel computer architectures. Then they describe the results of numerical simulations that demonstrate the effectiveness of the approach. Moreover, the proposed simulation solution is not limited to the applications of FDNEs in RTDS, it solves a set of subsistent computational issues when apply rational models in real‐time electromagnetic transients programs tools.
Cross‐range resolution improvement in forward‐looking imaging radar using autoregressive model‐based data extrapolation
Authors: Cho Byung‐Lae , Sun Sun‐Gu
Published: September 2015

The authors propose an extrapolation method to improve cross‐range resolution in forward‐looking imaging radar with multi‐input/dual‐output configuration. The extrapolation, which is based on autoregressive (AR) model, has different prediction directions according to the position of transmitting antennas. They tested the proposed method in a simulation with noise and in an actual experiment. In the simulation and experiment, the proposed method, which uses Burg method as an estimator of AR model, shows better image quality than other methods.
Invariant subspace detector in distributed multiple‐input multiple output radar: geometry gain helps improving moving target detection
Authors: Zaimbashi Amir
Published: September 2015

To detect moving targets in a distributed multiple‐input multiple output (MIMO) radars, it is preferable to null the clutter rather than whiten the clutter. This is mainly because clutter nulling approaches do not require range training data to form a sample covariance estimate of clutter in each transmit‐receive pair, especially in the distributed MIMO radars with non‐homogeneous clutter. Moreover, geometry diversity of the distributed MIMO helps improve moving target detection since for a given target velocity, different transmit‐receive pairs produce different Doppler frequencies that are less likely to be all small and reside in the clutter nulling region. Based on these facts, the authors consider a subspace model for clutter and derive a uniformly most powerful invariant (UMPI) detector as an optimum invariant test. In this case, analytical expressions for calculating the false alarm and detection probabilities for Swerling 0 and Swerling 1 target models are derived in the closed‐forms. Moreover, theoretical and numerical analyses of the proposed UMPI test are represented for several scenarios. More importantly, the simulation results show that the proposed subspace‐based UMPI detector can attain the predetermined false alarm probability and superior detection performance in the presence of correlated clutter. Finally, authors consider a situation in which perfect waveform separations at the local receivers are no longer valid, and see the detection performance degradation of the proposed optimal detector designed for ideal waveform separations.
Medizintechnologische Highlights in der Endoskopie: Vergangenheit und Zukunft – Teil 2
Authors: Schulz H.-J.
Published: September 2015

Die Einführung der Endoskopischen Papillotomie (EPT) durch Demling und Classen sowie Kawai im Jahre 1973 war ein Meilenstein in der Entwicklung der therapeutischen Endoskopie. Die Behandlungen sind heute ein fester Bestandteil der flexiblen Endoskopie. Methodenspektrum und Indikationen erweitern sich ständig.
Dielectrophoretic capture of low abundance cell population using thick electrodes
Authors: Marchalot Julien , Chateaux Jean-François , Faivre Magalie , Mertani Hichem C. , Ferrigno Rosaria , Deman Anne-Laure
Published: September 2015

Enrichment of rare cell populations such as Circulating Tumor Cells (CTCs) is a critical step before performing analysis. This paper presents a polymeric microfluidic device with integrated thick Carbon-PolyDimethylSiloxane composite (C-PDMS) electrodes designed to carry out dielectrophoretic (DEP) trapping of low abundance biological cells. Such conductive composite material presents advantages over metallic structures. Indeed, as it combines properties of both the matrix and doping particles, C-PDMS allows the easy and fast integration of conductive microstructures using a soft-lithography approach while preserving O2 plasma bonding properties of PDMS substrate and avoiding a cumbersome alignment procedure. Here, we first performed numerical simulations to demonstrate the advantage of such thick C-PDMS electrodes over a coplanar electrode configuration. It is well established that dielectrophoretic force (FDEP) decreases quickly as the distance from the electrode surface increases resulting in coplanar configuration to a low trapping efficiency at high flow rate. Here, we showed quantitatively that by using electrodes as thick as a microchannel height, it is possible to extend the DEP force influence in the whole volume of the channel compared to coplanar electrode configuration and maintaining high trapping efficiency while increasing the throughput. This model was then used to numerically optimize a thick C-PDMS electrode configuration in terms of trapping efficiency. Then, optimized microfluidic configurations were fabricated and tested at various flow rates for the trapping of MDA-MB-231 breast cancer cell line. We reached trapping efficiencies of 97% at 20 μl/h and 78.7% at 80 μl/h, for 100 μm thick electrodes. Finally, we applied our device to the separation and localized trapping of CTCs (MDA-MB-231) from a red blood cells sample (concentration ratio of 1:10).
Multiple solutions for Schrödinger-Poisson type equation with magnetic field
Authors: Zhu Anqiang , Sun Xiaomei
Published: September 2015

In this paper, we consider the multiplicity and concentration behavior for a nonlinear Schrödinger-Poisson type equation with magnetic field. By penalization method and Ljusternik-Schnirelmann theory, we present the relationship between the number of solutions and the topology of the set where the potential attains its minimum value.
A distributed-absorber cold-electron bolometer single pixel at 95 GHz
Authors: Mahashabde S. , Tarasov M. A. , Salatino M. , Sobolev A. , Masi S. , Kuzmin L. S. , de Bernardis P.
Published: September 2015

We describe a Frequency Selective Surface (FSS) based distributed-absorber Cold-Electron Bolometer (CEB) pixel at 95 GHz integrated in a multi-moded horn. The FSS provides a resonant interaction with incident mm and sub-mm radiation and defines the bandwidth of the array while the horn provides the matching of the beam to the telescope optics. CEB detectors with matched impedance are integrated within the periodic elements of the FSS and generate a voltage response proportional to the incident optical power in the bandwidth of the FSS. A prototype pixel was designed, fabricated, and characterized at a temperature of 280 mK. We present optical response to blackbody radiation and fit it to the CEB model. For an absorbed power of 50 pW, we estimate an optical responsivity of 1.2 × 108 V/W and a readout dominated Noise Equivalent Power (NEP) of 1.8 × 10−15 W Hz−1/2. A measured bandwidth of 9 GHz of this detector array confirms the frequency selective nature. This prototype represents a possible solution as a detector for the 95 GHz channel of the SWIPE instrument on the LSPE balloon-borne telescope. This kind of FSS based mm-wave architecture can be easily scaled to other frequency ranges and used on any other balloon-borne telescope focal planes.
A reductionist perspective on quantum statistical mechanics: Coarse-graining of path integrals
Authors: Sinitskiy Anton V. , Voth Gregory A.
Published: September 2015

Computational modeling of the condensed phase based on classical statistical mechanics has been rapidly developing over the last few decades and has yielded important information on various systems containing up to millions of atoms. However, if a system of interest contains important quantum effects, well-developed classical techniques cannot be used. One way of treating finite temperature quantum systems at equilibrium has been based on Feynman’s imaginary time path integral approach and the ensuing quantum-classical isomorphism. This isomorphism is exact only in the limit of infinitely many classical quasiparticles representing each physical quantum particle. In this work, we present a reductionist perspective on this problem based on the emerging methodology of coarse-graining. This perspective allows for the representations of one quantum particle with only two classical-like quasiparticles and their conjugate momenta. One of these coupled quasiparticles is the centroid particle of the quantum path integral quasiparticle distribution. Only this quasiparticle feels the potential energy function. The other quasiparticle directly provides the observable averages of quantum mechanical operators. The theory offers a simplified perspective on quantum statistical mechanics, revealing its most reductionist connection to classical statistical physics. By doing so, it can facilitate a simpler representation of certain quantum effects in complex molecular environments.
Large tunnel magnetoresistance ratio in Fe/O/NaCl/O/Fe
Authors: Gong Kui , Zhang Lei , Liu Lei , Zhu Yu , Yu Guanghua , Grutter Peter , Guo Hong
Published: September 2015

Magnetic tunnel junction (MTJ) is an important device element for many practical spintronic systems. In this paper, we propose and theoretically investigate a very attractive MTJ Fe(001)/O/NaCl(001)/O/Fe(001) as a two-terminal transport junction. By density functional theory total energy methods, we establish two viable device models: one with and the other without mirror symmetry across the center plane of the structure. Large tunnel magnetoresistance ratio (TMR) is predicted from first principles, at over 1800% and 3600% depending on the symmetry. Microscopically, a spin filtering effect is responsible for the large TMR. This effect essentially filters out all the minority spin channels (spin-down) from contributing to the tunnelling current. On the other hand, transport of the majority spin channel (spin-up) having Δ1 and Δ5 symmetry is enhanced by the FeO buffer layer in the MTJ.
Exciton dynamics in individual semimagnetic (Zn,Mn)Te/(Zn,Mg)Te nanowires
Authors: Gałkowski K. , Wojnar P. , Janik E. , Papierska J. , Sawicki K. , Kossacki P. , Suffczyński J.
Published: September 2015

Dynamics and mechanisms of photocreated carriers decay in individual core/shell (Zn,Mn)Te/(Zn,Mg)Te semimagnetic nanowires are studied with a high temporal resolution. Exciton lifetime determined to 44 ± 5 ps is found to increase to 78 ± 5 ps upon application of magnetic field of up to 10 T. A quantitative modeling attributes the effects observed in time-resolved and time-integrated micro-photoluminescence to the magnetic field induced quenching of exchange Auger type, non-radiative carrier recombination related to Mn2+ ions. The reported properties of the semimagnetic nanowires are promising for their implementation in high-speed devices exploiting light-induced conductivity.
A nanowaveguide platform for collective atom-light interaction
Authors: Meng Y. , Lee J. , Dagenais M. , Rolston S. L.
Published: September 2015

We propose a nanowaveguide platform for collective atom-light interaction through evanescent field coupling. We have developed a 1 cm-long silicon nitride nanowaveguide can use evanescent fields to trap and probe an ensemble of 87Rb atoms. The waveguide has a sub-micrometer square mode area and was designed with tapers for high fiber-to-waveguide coupling efficiencies at near-infrared wavelengths (750 nm to 1100 nm). Inverse tapers in the platform adiabatically transfer a weakly guided mode of fiber-coupled light into a strongly guided mode with an evanescent field to trap atoms and then back to a weakly guided mode at the other end of the waveguide. The coupling loss is −1 dB per facet (∼80% coupling efficiency) at 760 nm and 1064 nm, which is estimated by a propagation loss measurement with waveguides of different lengths. The proposed platform has good thermal conductance and can guide high optical powers for trapping atoms in ultra-high vacuum. As an intermediate step, we have observed thermal atom absorption of the evanescent component of a nanowaveguide and have demonstrated the U-wire mirror magneto-optical trap that can transfer atoms to the proximity of the surface.
Adaptabilities of three mainstream short-term wind power forecasting methods
Authors: Yan Jie , Gao Xiaoli , Liu Yongqian , Han Shuang , Li Li , Ma Xiaomei , Gu Chenghong , Bhakar Rohit , Li Furong
Published: September 2015

Variability and intermittency of wind is the main challenge for making a reliable wind power forecasting (WPF). Meteorological and topological complexities make it even harder to fit any forecasting algorithm to one particular case. This paper presents the comparison of three short term WPF models based on three wind farms in China with different terrains and climates. The sensitivity effects of training samples on forecasting performance are investigated in terms of sample size, sample quality, and sample time scale. Then, their adaptabilities and modeling efficiency are also discussed under different seasonal and topographic conditions. Results show that (1) radial basis function (RBF) and support vector machine (SVM) generally have higher prediction accuracy than that of genetic algorithm back propagation (GA-BP), but different models show advantages in different seasons and terrains. (2) WPF taking a month as the training time interval can increase the accuracy of short-term WPF. (3) The change of sample number for the GA-BP and RBF is less sensitive than that of the SVM. (4) GA-BP forecasting accuracy is equally sensitive to all size of training samples. RBF and SVM have different sensibility to different size of training samples. This study can quantitatively provide reference for choosing the appropriate WPF model and further optimization for specific engineering cases, based on better understanding of algorithm theory and its adaptability. In this way, WPF users can select the suitable algorithm for different terrains and climates to achieve reliable prediction for market clearing, efficient pricing, dispatching, etc.
Fracture dynamics in implanted silicon
Authors: Massy D. , Mazen F. , Tardif S. , Penot J. D. , Ragani J. , Madeira F. , Landru D. , Kononchuk O. , Rieutord F.
Published: September 2015

Crack propagation in implanted silicon for thin layer transfer is experimentally studied. The crack propagation velocity as a function of split temperature is measured using a designed optical setup. Interferometric measurement of the gap opening is performed dynamically and shows an oscillatory crack “wake” with a typical wavelength in the centimetre range. The dynamics of this motion is modelled using beam elasticity and thermodynamics. The modelling demonstrates the key role of external atmospheric pressure during crack propagation. A quantification of the amount of gas trapped inside pre-existing microcracks and released during the fracture is made possible, with results consistent with previous studies.
Note: Derivation of two-photon circular dichroism—Addendum to “Two-photon circular dichroism” [J. Chem. Phys. 62, 1006 (1975)]
Authors: Friese Daniel H.
Published: September 2015

This addendum shows the detailed derivation of the fundamental equations for two-photon circular dichroism which are given in a very condensed form in the original publication [I. Tinoco, J. Chem. Phys. 62, 1006 (1975)]. In addition, some minor errors are corrected and some of the derivations in the original publication are commented.
Optical band gap transition from direct to indirect induced by organic content of CH3NH3PbI3 perovskite films
Authors: Ke Xiaohan , Yan Jun , Zhang Ao , Zhang Bing , Chen Yunlin
Published: September 2015

Most of the systematic studies on tuning the band gap in the family of organolead halide perovskites have focused on changing the compositions of halogens. Here, the effects of varying the organic content on the band gap of CH3NH3PbI3 were studied. The methylammonium lead iodide (CH3NH3PbI3) films were fabricated with different molar ratios of CH3NH3I to PbI2. We found that the films become compact and the crystalline size decreased from 6.0 to 0.2 μm and the optical band gap of CH3NH3PbI3 could be transferred from direct to indirect with increasing CH3NH3I content in the precursor. The experimental results demonstrated that the existence of the indirect band gap in CH3NH3PbI3 film and the CH3NH3I content plays a key role in adjusting the film morphology and optical band. The investigation of the optical band transition induced by changing organic content could provide a different view on studying CH3NH3PbI3 materials.
Directed fast electron beams in ultraintense picosecond laser irradiated solid targets
Authors: Ge X. L. , Lin X. X. , Yuan X. H. , Carroll D. C. , Gray R. J. , Yu T. P. , Tresca O. , Chen M. , Liu F. , Zhuo H. B. , Zielbauer B. , Zhao L. , Neely D. , Sheng Z. M. , Li Y. T. , McKenna P.
Published: September 2015

We report on fast electron transport and emission patterns from solid targets irradiated by s-polarized, relativistically intense, picosecond laser pulses. A beam of multi-MeV electrons is found to be transported along the target surface in the laser polarization direction. The spatial-intensity and energy distributions of this beam are compared with the beam produced along the laser propagation axis. It is shown that even for peak laser intensities an order of magnitude higher than the relativistic threshold, laser polarization still plays an important role in electron energy transport. Results from 3D particle-in-cell simulations confirm the findings. The characterization of directional beam emission is important for applications requiring efficient energy transfer, including secondary photon and ion source development.
The demonstration of promising Ge n-type multi-gate-field-effect transistors with the magnetic FePt metal gate scheme
Authors: Liao M.-H. , Huang S. C.
Published: September 2015

In this work, the tetragonal-phase BaTiO3 high dielectric (HK) layer and the magnetic FePt metal gate (MG) film are proposed to be the gate stack scheme on the Ge three dimensional (3D) n-type multi-gate-field-effect transistors (FETs). The ∼75% dielectric constant (κ-value) improvement, ∼100× gate leakage (Jg) reduction, and ∼70% on-state current (Ion) enhancement are achieved due to the colossal magneto-capacitance effect. The magnetic field from the magnetic FePt MG film couples and triggers more dipoles in the BaTiO3 HK layer and then results in the super gate stack characteristics. The promising transistor's performance (∼200 μA/μm on the device with the gate length Lch = 60 nm) on the high mobility (Ge) material in the 3D n-type multi-gate-FETs device structure demonstrated in this work provides the useful solution for the future advanced logic device design.
Optically induced strong intermodal coupling in mechanical resonators at room temperature
Authors: Ohta R. , Okamoto H. , Hey R. , Friedland K. J. , Yamaguchi H.
Published: September 2015

Strong parametric mode coupling in mechanical resonators is demonstrated at room temperature by using the photothermal effect in thin membrane structures. Thanks to the large stress modulation by laser irradiation, the coupling rate of the mechanical modes, defined as half of the mode splitting, reaches 2.94 kHz, which is an order of magnitude larger than electrically induced mode coupling. This large coupling rate exceeds the damping rates of the mechanical resonators and results in the strong coupling regime, which is a signature of coherent mode interaction. Room-temperature coherent mode coupling will enable us to manipulate mechanical motion at practical operation temperatures and provides a wide variety of applications of integrated mechanical systems.
Direct observation of a gap opening in topological interface states of MnSe/Bi2Se3 heterostructure
Authors: Matetskiy A. V. , Kibirev I. A. , Hirahara T. , Hasegawa S. , Zotov A. V. , Saranin A. A.
Published: September 2015

High-quality MnSe(111) film was bilayer-by-bilayer grown epitaxially onto the Bi2Se3(111) surface using molecular beam epitaxy. Reversal scenario with quintuple layer-by-layer growth of Bi2Se3 onto the MnSe film was also realized. Angle-resolved photoemission spectroscopy measurements of Bi2Se3 capped with two bi-layers of MnSe revealed that an energy gap of about 90 meV appears at the Dirac point of the original Bi2Se3 surface, possibly due to breaking the time-reversal symmetry on the Bi2Se3 surface by magnetic proximity effect from MnSe.
Physiological characterisation and fine mapping of a salt-tolerant mutant in rice (Oryza sativa)
Authors: Deng Ping , Jiang Dan , Dong Yanmin , Shi Xingyu , Jing Wen , Zhang Wenhua
Published: September 2015

Salt-tolerant mutants are valuable resources for basic and applied research on plant salt tolerance. Here, we report the isolation and characterisation of a salt-tolerant rice (Oryza sativa L.) mutant. This mutant was identified from an ethyl methanesulfonate-induced Nipponbare mutant library, designated as rice salt tolerant 1 (rst1). The rst1 mutant was tolerant to salt stress and showed significantly higher shoot biomass and chlorophyll content, but lower lipid peroxidation and electrolyte leakage under NaCl stress. The improved salt tolerance of this mutant may be due mainly to its enhanced ability to restrict Na+ accumulation in shoots under salt stress conditions. Genetic analysis indicated that the salt tolerance of the rst1 mutant was controlled by a single recessive gene. Quantitative trait locus (QTL) mapping for salt tolerance was performed using an F2 population of rst1 × Peiai 64. Two QTLs were detected, in which the locus on chromosome 6 was determined to be the candidate locus of the rst1 gene. The rst1 locus was subsequently shown to reside within a 270.4-kb region defined by the markers IM29432 and IM29702. This result will be useful for map-based cloning of the rst1 gene and for marker-assisted breeding for salt tolerance in rice.
Torres Strait Islanders‘ understandings of chronic hepatitis B and attitudes to treatment
Authors: Anderson Elayne , Ellard Jeanne , Wallace Jack
Published: September 2015

Indigenous Australians are disproportionally affected by hepatitis B compared with non-Indigenous Australians. The higher prevalence of hepatitis B among Indigenous Australians has been linked to an increased incidence of liver cancer in this population. There is evidence that comprehensive programs of hepatitis B virus management, which include liver cancer surveillance and appropriate antiviral therapy, offer a cost-effective approach to reduce the incidence of liver cancer in Australia. This paper reports on data from the first study investigating understandings of hepatitis B and attitudes to treatment among Torres Strait Islanders living with chronic hepatitis B. Forty-two participants completed an interview questionnaire. Participants typically had an unclear understanding of hepatitis B and reported significant gaps in monitoring and follow up. A majority of participants indicated a willingness to use treatment if required. The findings of this study suggest the need for a new service delivery model that is appropriate to remote communities such as the Torres Strait Islands, to improve hepatitis B follow up, disease monitoring and management, and where appropriate, the uptake of treatment.
Does a land‐based compensatory strength‐training programme influences the rotator cuff balance of young competitive swimmers?
Authors: Batalha Nuno , Raimundo Armando , Tomas‐Carus Pablo , Paulo João , Simão Roberto , Silva António J.
Published: September 2015

During the repeated execution of the swimming strokes, the shoulder adductor and internal rotator muscles have a tendency to become proportionally stronger when compared to their antagonist group. This can lead to muscle imbalances. The aim of this study was to examine the effects of a compensatory training programme on the strength and balance of shoulder rotator muscles in young swimmers. A randomized controlled trial design was used. Forty male swimmers took part in the study and were randomly divided into two groups: an experimental group (n = 20) and a training group (n = 20). A control group (n = 16) of young sedentary male students was also evaluated. The experimental group subjects participated in a 16‐week shoulder‐strength programme with Thera‐Band® elastic bands; the training group was restricted to aquatic training. Peak torque of shoulder internal rotator and external rotator (ER) was measured at baseline and after 16 weeks. Concentric action at 1.04 rad s−1 (3 reps) and 3.14 rad s−1 (20 reps) was measured using an isokinetic dynamometer. The strength‐training programme led to an improvement of the ER strength and shoulder rotator balance in the experimental group (data from both shoulders at 1.04 rad s−1). Moreover, concentric action at 3.14 rad s−1 presented significant differences only for the dominant shoulder. Findings suggest that the prescribed shoulder‐strengthening exercises could be a useful training option for young competitive swimmers. They can produce an increase in absolute strength values and greater muscle balance in shoulder rotators.
Organic Label, Bargaining Power, and Profit‐sharing in the French Fluid Milk Market
Authors: Bonnet Céline , Bouamra-Mechemache Zohra
Published: September 2015

The paper determines how the value‐added created by an organic label is shared in a vertical chain among manufacturers and retailers. Using purchase data on the French fluid milk sector, we develop a structural econometric model of demand and supply that takes into account the bargaining power between manufacturers and retailers. Our results suggest that the organic label segment is more profitable, as it permits the existence of higher margins. Moreover, an organic label allows manufacturers to achieve more bargaining power relative to retailers, and hence to obtain a higher share of total margins. The econometric model is then used to assess the impact of an environmental policy in favor of the organic segment based on a mechanism of price support. Our results suggest that while a subsidy policy towards organic products benefits both manufacturers and retailers, a tax policy toward conventional products benefits manufacturers of national brands at the expense of retailers and manufacturers that provide the private labels. The benefits of such policies on the environment is relatively small. All such policies tend to increase the impact on global warming and land use, but reduce the impact on eutrophication, acidification, and energy use.
Extensive Recruitment of Plasma Blasts to the Cerebrospinal Fluid in Toscana Virus Encephalitis
Authors: Schirmer Lucas , Wölfel Silke , Georgi Enrico , Ploner Markus , Bauer Barbara , Hemmer Bernhard
Published: September 2015

An unexpectedly extensive recruitment of B cells and plasma blasts to the cerebrospinal fluid (CSF) in a patient with Toscana virus (TOSV) encephalitis is described. Acute infection by TOSV was demonstrated by serological methods and by detection of TOSV-specific nucleic acid in the CSF by real-time polymerase chain reaction and sequencing.
SN2‐Palmitate Reduces Fatty Acid Excretion in Chinese Formula‐fed Infants
Authors: Bar‐Yoseph Fabiana , Lifshitz Yael , Cohen Tzafra , Malard Patrice , Xu Chungdi
Published: September 2015

Objectives:

Palmitic acid (PA) comprises 17% to 25% of human milk fatty acids, of which 70% to 75% are esterified to the SN2 position of the triglyceride (SN2‐palmitate). In vegetable oils, which are commonly used in infant formulas, palmitate is primarily esterified to other positions, resulting in reduced calcium and fat absorption and hard stools. The aim of this study was to elucidate the effects of SN2‐palmitate on nutrient excretion.

Methods:

In total, 171 Chinese infants were included (within 14 days of birth) in this multicenter study. Formula‐fed infants were randomly assigned to receive either SN2‐palmitate formula (INFAT, n = 57) or control formula (n = 57). The formulas (Biostime, China) differed only in their SN2 PA proportions. Stool was collected at 6 postnatal weeks.

Results:

The stool dry weight and fat content of the SN2‐palmitate group were lower compared with the control group (dry weight 4.25 g vs 7.28 g, P < 0.05; fat 0.8 g vs 1.2 g, P < 0.05). The lipid component was also significantly lower for the SN2‐palmitate group (0.79 g vs 1.19 g, P < 0.05). PA, representing ∼50% of the saponified fatty acids, was significantly lower in the SN2‐palmitate group compared with the control group (0.3 g vs 0.7 g, P < 0.01). Breast‐fed infants had a significantly lower stool dry weight, fat content, and saponified fat excretion compared with formula‐fed infants (P < 0.01).

Conclusions:

Similar to breast milk, the SN2‐palmitate infant formula primarily reduced calcium‐saponified fat excretion. The results of this study further emphasize the nutritional importance of SN2‐palmitate structured fat for infants.
Editorial
Authors: Stuart Trevor
Published: September 2015

Volume 61 of
Biographical Memoirs
contains 26 accounts of Fellows and Foreign Members who died recently. This is a greater number than has been the case for some years. Of the 26 memoirs, 20 come from the physical and engineering sciences and only 6 from the biomedical sciences, but one of the former group, Michael Fasham, is partly biological. However, the latter group includes two outstanding scientists and Nobel laureates. Fred Sanger, whose memoir was written by George Brownlee, was a committed molecular biologist who uniquely won the Nobel Prize twice, once in 1958 for protein sequencing and again in 1980 for the sequencing of nucleic acids. He stimulated our understanding of the chemistry of many proteins and enzymes and, moreover, his ingenious DNA sequencing method revolutionized molecular biology. Robert Edwards's memoir was written by Richard Gardner, who explains that Edwards was responsible for the most significant advance in the treatment of human fertility, the development of
in vitro
fertilization (IVF), for which he was awarded the Nobel Prize in 2010. He persisted in his work in spite of vehement opposition from all quarters. However, the first of many IVF successes came in a live birth in 1978. Edwards was also noted for the diagnosis of genetic disease and the use of stem cells in regenerative medicine.
Sampling networks of ecological interactions
Authors: Jordano Pedro
Published: September 2015

Sampling ecological interactions presents similar challenges, problems, potential biases, and constraints as sampling individuals and species in biodiversity inventories. Interactions are just pairwise relationships among individuals of two different species, such as those among plants and their seed dispersers in frugivory interactions or those among plants and their pollinators. Sampling interactions is a fundamental step to build robustly estimated interaction networks, yet few analyses have attempted a formal approach to their sampling protocols.

Robust estimates of the actual number of interactions (links) within diversified ecological networks require adequate sampling effort that needs to be explicitly gauged. Yet we still lack a sampling theory explicitly focusing on ecological interactions.

While the complete inventory of interactions is likely impossible, a robust characterization of its main patterns and metrics is probably realistic. We must acknowledge that a sizable fraction of the maximum number of interactionsImaxamong, say,Aanimal species andPplant species (i.e.,Imax=AP) is impossible to record due to forbidden links, i.e., life-history restrictions. Thus, the number of observed interactionsIin robustly sampled networks is typicallyI ≪ Imax, resulting in extremely sparse interaction matrices with low connectance.

Reasons for forbidden links are multiple but mainly stem from spatial and temporal uncoupling, size mismatches, and intrinsically low probabilities of interspecific encounter for most potential interactions of partner species. Ad-equately assessing the completeness of a network of ecological interactions thus needs knowledge of the natural history details embedded, so that for-bidden links can be “discounted” when addressing sampling effort.

Here I provide a review and outline a conceptual framework for interaction sampling by building an explicit analogue to individuals and species sampling, thus extending diversity-monitoring approaches to the characterization of complex networks of ecological interactions. This is crucial to assess the fast-paced and devastating effects of defaunation-driven loss of key ecological interactions and the services they provide and the analogous losses related to interaction gains due to invasive species and biotic homogenization.
Genomic and phenotypic evidence for an incomplete domestication of South American grain amaranth (Amaranthus caudatus)
Authors: Stetter Markus G. , Müller Thomas , Schmid Karl J.
Published: September 2015

The process of domestication leads to major morphological and genetic changes, which in combination are known as domestication syndrome that differentiates crops from their wild ancestors. We characterized the genomic and phenotypic diversity of the South American grain amaranthAmaranthus caudatus, which has been cultivated for thousands of years and is one of the three native grain amaranths of South and Central America. Previously, several models of domestication were proposed including a domestication from the close relatives and putative ancestorsA. hybridusorA. quitensis. To investigate the evolutionary relationship ofA. caudatusand its two close relatives, we genotyped 119 amaranth accessions of the three species from the Andean region using genotyping-by-sequencing (GBS) and compared phenotypic variation in two domestication-related traits, seed size and seed color. The analysis of 9,485 SNPs revealed a strong genetic differentiation of cultivatedA. caudatusfrom the relativesA. hybridusandA. quitensis. The two relatives did not cluster according to the species assigment but formed mixed groups according to their geographic origin in Ecuador and Peru, respectively.A. caudatushad a higher genetic diversity than its close relatives and shared a high proportion of polymorphisms with their wild relatives consistent with the absence of a strong bottleneck or a high level of recent gene flow. Genome sizes and seed sizes were not significantly different betweenA. caudatusand its relatives, although a genetically distinct group ofA. caudatusfrom Bolivia had significantly larger seeds. We conclude that despite a long history of human cultivation and selection for white grain color,A. caudatusshows a weak genomic and phenotypic domestication syndrome and is an incompletely domesticated species because of weak selection or high levels of gene flow from its sympatric close undomesticated relatives that counteracted the fixation of key domestication traits.
Allele-specific expression reveals interactions between genetic variation and environment
Authors: Knowles David A , Davis Joe R , Raj Anil , Zhu Xiaowei , Potash James B , Weissman Myrna M , Shi Jianxin , Levinson Douglas F , Mostafavi Sara , Montgomery Stephen B , Battle Alexis
Published: September 2015

The impact of environment on human health is dramatic, with major risk factors including substance use, diet and exercise. However, identifying interactions between the environment and an individual's genetic background (GxE) has been hampered by statistical and computational challenges. By combining RNA sequencing of whole blood and extensive environmental annotations collected from 922 individuals, we have evaluated GxE interactions at a cellular level. We have developed EAGLE, a hierarchical Bayesian model for identifying GxE interactions based on association between environment and allele-specific expression (ASE). EAGLE increases power by leveraging the controlled, within-sample comparison of environmental impact on different genetic backgrounds provided by ASE, while also taking into account technical covariates and over-dispersion of sequencing read counts. EAGLE identifies 35 GxE interactions, a substantial increase over standard GxE testing. Among EAGLE hits are variants that modulate response to smoking, exercise and blood pressure medication. Further, application of EAGLE identifies GxE interactions to infection response that replicate results reported in vitro, demonstrating the power of EAGLE to accurately identify GxE candidates from large RNA sequencing studies.
Sampling the conformational space of the catalytic subunit of human γ-secretase
Authors: Bai Xiao-chen , Rajendra Eeson , Yang Guanghui , Shi Yigong , W Scheres Sjors H.
Published: September 2015

Human γ-secretase is an intra-membrane protease that cleaves many different substrates. Aberrant cleavage of Notch is implicated in cancer, while abnormalities in cutting amyloid precursor protein lead to Alzheimer’s disease. Our previous cryo-EM structure of γ-secretase revealed considerable disorder in its catalytic subunit presenilin. Here, we introduce an image classification procedure that characterizes molecular plasticity at the secondary structure level, and apply this method to identify three distinct conformations in our previous sample. In one of these conformations, an additional transmembrane helix is visible that cannot be attributed to the known components of γ-secretase. In addition, we present a γ-secretase structure in complex with the dipeptidic inhibitorN-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycinet-butyl ester (DAPT). Our results reveal how conformational mobility in the second and sixth transmembrane helices of presenilin is greatly reduced upon binding of DAPT or the additional helix, and form the basis for a new model of how substrate enters the transmembrane domain.
Britain in bloom? A study into Chinese tourists’ experience
Authors: Lin Zhibin , He Guangren , Vlachos Ilias P.
Published: September 2015

Purpose

– The purpose of this paper is to examine Chinese tourists’ experience of Britain based on a conceptual model of tourist satisfaction and destination loyalty, and to identify key issues that tourism organisations could address to provide an excellent experience for Chinese tourists.

Design/methodology/approach

– Data were collected in collaboration with a tour operator; and 275 valid responses were received. Partial Least Square Structural Equation Modelling was used for data analysis.

Findings

– The key destination attributes of Britain such as heritage sites, natural scenery and customer service provide an excellent experience for Chinese tourists. Other British destination attributes such as shopping facilities, food, accommodation, entertainment and night life are less impressive.

Research limitations/implications

– The sample was drawn from Chinese tourists visiting Britain on package tours, which limits the generalisation of results to other Chinese tourists and other European/Mediterranean destinations.

Practical implications

– There are two key challenges for British destination tourism managers: first, to maintain the current quality levels in the attributes that generate tourist satisfaction; and second, to concentrate on improving attributes with low performance ratings such as shopping, food and drink, accommodation, entertainment and night life. As the characteristics of Chinese tourists are culture-specific rather than destination-specific, tourism managers in other European destinations may find these recommendations useful too.

Originality/value

– This is one of the first studies to examine Chinese tourists’ experience of a European destination. The results reveal unique characteristics of Chinese tourist requirements, which provide useful implications for tourism organisations to adapt their service strategies to better cater to this growing group of travellers.