bluuebunny/crossref_metadata_2025 huggingface dataset:
Correction: Corrigendum: Building an organic computing device with multiple interconnected brains
Authors: Pais-Vieira Miguel , Chiuffa Gabriela , Lebedev Mikhail , Yadav Amol , Nicolelis Miguel A. L.
Published: October 2015

Recently, we proposed that Brainets, i.e. networks formed by multiple animal brains, cooperating and exchanging information in real time through direct brain-to-brain interfaces, could provide the core of a new type of computing device: an organic computer. Here, we describe the first experimental demonstration of such a Brainet, built by interconnecting four adult rat brains. Brainets worked by concurrently recording the extracellular electrical activity generated by populations of cortical neurons distributed across multiple rats chronically implanted with multi-electrode arrays. Cortical neuronal activity was recorded and analyzed in real time, and then delivered to the somatosensory cortices of other animals that participated in the Brainet using intracortical microstimulation (ICMS). Using this approach, different Brainet architectures solved a number of useful computational problems, such as discrete classification, image processing, storage and retrieval of tactile information, and even weather forecasting. Brainets consistently performed at the same or higher levels than single rats in these tasks. Based on these findings, we propose that Brainets could be used to investigate animal social behaviors as well as a test bed for exploring the properties and potential applications of organic computers.
Elevation of ω-3 Polyunsaturated Fatty Acids Attenuates PTEN-deficiency Induced Endometrial Cancer Development through Regulation of COX-2 and PGE2 Production
Authors: Pan Jinshun , Cheng Lixian , Bi Xinyun , Zhang Xin , Liu Shanshan , Bai Xiaoming , Li Fanghong , Zhao Allan Z.
Published: October 2015

Endometrial cancer is one of the most common gynecologic malignancies. Phosphatase and tensin homologue (PTEN)-mutation is frequently identified in endometrial cancer patients. Although high dietary intake of ω-3 polyunsaturated fatty acids (PUFAs) has been associated with reduced risk of endometrial cancer, the underlying mechanisms is still unknown. To this end, we evaluated the impact of ω-3 PUFAs using several endometrial cancer cellular and animal models. While ~27% and 40% of heterozygotic PTEN mutant mice developed endometrial cancer and atypical complex hyperplasia, respectively, none of the PTEN+/− mice developed cancer when we overexpressed an mfat-1 transgene, which allowed endogenous production of ω-3 PUFAs. Fish oil-enriched diet or expression of mfat-1 transgene significantly inhibited the growth of xenograft tumor derived from RL95-2 cells bearing a PTEN null mutation. At cellular level, ω-3 PUFAs treatment decreased the viability of RL95-2 cells, AKT phosphorylation and cyclin D1 expression. These molecular events are primarily mediated through reduction of cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) production. Exogenous PGE2 treatment completely blunted the impact of ω-3 PUFAs on endometrial cancer. Thus, we revealed the direct inhibitory effects of ω-3 PUFAs on endometrial cancer development and the underlying mechanisms involving reduction of COX-2 and PGE2.
Key evidence of the role of desertification in protecting the underlying permafrost in the Qinghai–Tibet Plateau
Authors: Xie Shengbo , Qu Jianjun , Lai Yuanming , Xu Xiangtian , Pang Yingjun
Published: October 2015

Previous research has shown that the temperature of underlying permafrost decreases after the ground surface is covered with sand. No significant conclusions have yet been drawn that explain why this happens, because the heat transfer mechanism effects of the sand layer on the underlying permafrost remain unclear. These mechanisms were studied in the present work. We found that the upward shortwave radiation flux of the Qinghai-Tibet Plateau ground surface with a sand layer covering was higher than that of the surface without sand; thus, the atmospheric heat reflected by the sand layer is greater than that reflected by the surface without sand. Therefore, the net radiation of the surface with the sand layer is lower than that of the surface without sand, which reduces the heat available to warm the sand layer. Because sand is both a porous medium and a weak pervious conductor with poor heat conductivity, less heat is conducted through the sand layer to the underground permafrost than in soil without the sand deposition layer. This phenomenon results in a decrease in the ground temperature of the permafrost under the sand layer, which plays a key role in protecting the permafrost.
Microwave field frequency and current density modulated skyrmion-chain in nanotrack
Authors: Ma Fusheng , Ezawa Motohiko , Zhou Yan
Published: October 2015

Magnetic skyrmions are promising candidates as information carriers for the next-generation spintronic devices because of their small size, facile current-driven motion and topological stability. The controllable nucleation and motion of skyrmions in magnetic nanostructures will be essential in future skyrmionic devices. Here, we present the microwave assisted nucleation and motion of skyrmion-chains in magnetic nanotrack by micromagnetic simulation. A skyrmion-chain is a one-dimensional cluster of equally spaced skyrmions. A skyrmion-chain conveys an integer bit n when it consists of n skyrmions. A series of skyrmion-chains with various lengths is generated and moved in the nanotrack driven by spin-polarized current. The period, length and spacing of the skyrmion-chains can be dynamically manipulated by controlling either the frequency of the microwave field or the time dependent spin-polarized current density. A skyrmion-chain behaves as a massless particle, where it stops without delay when the current is stopped. Their velocity is found to be linearly dependent on the current density and insensitive to the frequency and amplitude of the excitation microwave field. Uniform motion of trains of skyrmion-chains in nanotrack offers a promising approach for spintronic multi-bit memories containing series of skyrmion-chains to represent data stream.
Spatio-Temporal Pattern and Socio-Economic Factors of Bacillary Dysentery at County Level in Sichuan Province, China
Authors: Ma Yue , Zhang Tao , Liu Lei , Lv Qiang , Yin Fei
Published: October 2015

Bacillary dysentery (BD) remains a big public health problem in China. Effective spatio-temporal monitoring of BD incidence is important for successful implementation of control and prevention measures. This study aimed to examine the spatio-temporal pattern of BD and analyze socio-economic factors that may affect BD incidence in Sichuan province, China. Firstly, we used space-time scan statistic to detect the high risk spatio-temporal clusters in each year. Then, bivariate spatial correlation and Bayesian spatio-temporal model were utilized to examine the associations between the socio-economic factors and BD incidence. Spatio-temporal clusters of BD were mainly located in the northern-southern belt of the midwest area of Sichuan province. The proportion of primary industry, the proportion of rural population and the rates of BD incidence show statistically significant positive correlation. The proportion of secondary industry, proportion of tertiary Industry, number of beds in hospitals per thousand persons, medical and technical personnel per thousand persons, per capital GDP and the rate of BD incidence show statistically significant negative correlation. The best fitting spatio-temporal model showed that medical and technical personnel per thousand persons and per capital GDP were significantly negative related to the risk of BD.
Characteristics of dynamic cerebral autoregulation in cerebral small vessel disease: Diffuse and sustained
Authors: Guo Zhen-Ni , Xing Yingqi , Wang Shuang , Ma Hongyin , Liu Jia , Yang Yi
Published: October 2015

Cerebral small vessel disease is a major cause of stroke and vascular dementia; however, the pathogenesis is largely unclear. In this study, we investigated the characteristics of the impairment of dynamic cerebral autoregulation (dCA) in lacunar infarction patients. Seventy-one lacunar infarction patients were enrolled in the study, including 46 unilateral middle cerebral artery (MCA) territory stroke patients and 25 unilateral posterior cerebral artery (PCA) territory stroke patients. Each group of patients was randomly divided into two subgroups. Group 1 underwent dCA assessments in the bilateral MCAs and Group 2 underwent dCA assessments in the bilateral PCAs. All patients were followed up for 6 months. Transfer function analysis was applied to derive the autoregulatory parameters of gain and phase difference. In the unilateral MCA territory stroke patients, impairments of dCA were observed in both the MCAs and PCAs and the same results were observed in the unilateral PCA territory stroke patients. These impairments remained unchanged during the 6-month follow-up. In lacunar infarction, which is most prevalent type of cerebral small vessel disease, though patients with unilateral MCA territory/PCA territory stroke, the impairments of dCA were global and sustained. This finding suggests that the physiological changes associated with lacunar infarction were diffuse.
Structure and Properties of Silica Glass Densified in Cold Compression and Hot Compression
Authors: Guerette Michael , Ackerson Michael R. , Thomas Jay , Yuan Fenglin , Bruce Watson E. , Walker David , Huang Liping
Published: October 2015

Silica glass has been shown in numerous studies to possess significant capacity for permanent densification under pressure at different temperatures to form high density amorphous (HDA) silica. However, it is unknown to what extent the processes leading to irreversible densification of silica glass in cold-compression at room temperature and in hot-compression (e.g., near glass transition temperature) are common in nature. In this work, a hot-compression technique was used to quench silica glass from high temperature (1100 °C) and high pressure (up to 8 GPa) conditions, which leads to density increase of ~25% and Young’s modulus increase of ~71% relative to that of pristine silica glass at ambient conditions. Our experiments and molecular dynamics (MD) simulations provide solid evidences that the intermediate-range order of the hot-compressed HDA silica is distinct from that of the counterpart cold-compressed at room temperature. This explains the much higher thermal and mechanical stability of the former than the latter upon heating and compression as revealed in our in-situ Brillouin light scattering (BLS) experiments. Our studies demonstrate the limitation of the resulting density as a structural indicator of polyamorphism and point out the importance of temperature during compression in order to fundamentally understand HDA silica.
Mapping explosive residues on galvanized pipe bomb fragments using total vaporization solid phase microextraction (TV-SPME)
Authors: Bors Dana , Goodpaster John
Published: October 2015

Total Vaporization Solid Phase Microextraction (TV-SPME) can quantitate trace explosive residues on post-blast debris.
Nickel embedded in N-doped porous carbon for the hydrogenation of nitrobenzene to p-aminophenol in sulphuric acid
Authors: Wang Tao , Dong Zhen , Fu Teng , Zhao Yanchao , Wang Tian , Wang Yongzheng , Chen Yi , Han Baohang , Ding Weiping
Published: October 2015

An acid-resistant catalyst composed of nickel embedded in N-doped porous carbon for the catalytic hydrogenation of nitrobenzene to p-aminophenol.
A trifunctional cyclooctyne for modifying azide-labeled biomolecules with photocrosslinking and affinity tags
Authors: Stewart Jessica A. , Piligian Brent F. , Rundell Sarah R. , Swarts Benjamin M.
Published: October 2015

A trifunctional cyclooctyne-based reagent that harnesses bioorthogonal chemistry to facilitate the probing of biomolecular interactions is described.
Active biopolymers in green non-conventional media: a sustainable tool for developing clean chemical processes
Authors: Lozano Pedro , Bernal Juana M. , Nieto Susana , Gomez Celia , Garcia-Verdugo Eduardo , Luis Santiago V.
Published: October 2015

By understanding structure–function relationships of active biopolymers (e.g. enzymes and nucleic acids) in green non-conventional media, sustainable chemical processes may be developed.
An efficient planar-heterojunction solar cell based on wide-bandgap CH3NH3PbI2.1Br0.9 perovskite film for tandem cell application
Authors: Zhu Weidong , Bao Chunxiong , Li Faming , Zhou Xiaoxin , Yang Jie , Yu Tao , Zou Zhigang
Published: October 2015

The planar-heterojunction solar cell based on wide bandgap CH3NH3PbI2.1Br0.9 perovskite film shows an efficiency of 12.67% with negligible current hysteresis.
Finely tuning MOFs towards high-performance post-combustion CO2 capture materials
Authors: Wang Qian , Bai Junfeng , Lu Zhiyong , Pan Yi , You Xiaozeng
Published: October 2015

Schematic drawing of six strategies for fine tuning of MOF structures from prototypical MOFs.
Synthesis, crystal structures and magnetic properties of a family of manganese phosphonate clusters with diverse structures
Authors: Liu Jin-ying , Ma Cheng-bing , Chen Hui , Chen Chang-neng
Published: October 2015

Four manganese clusters containing tert-butylphosphonate ligands with diverse structures have been synthesized and characterized.
Selective catalytic reduction of NO by NH3 over CuO–CeO2 in the presence of SO2
Authors: Li Bo , Ren Zhiyuan , Ma Zhaoxia , Huang Xiaodong , Liu Fu , Zhang Xiaobin , Yang Hangsheng
Published: October 2015

The reaction between NO2 and NH3/NH4+ induced the formation of NHX<3 species with high oxidability; NHX<3 promoted the surface sulfate decomposition; high de-NOX performance was achieved in the presence of SO2 at low temperature.
Growth control of sessile microbubbles in PDMS devices
Authors: Volk Andreas , Rossi Massimiliano , Kähler Christian J. , Hilgenfeldt Sascha , Marin Alvaro
Published: October 2015

A bubble in an advanced growth state inside a microchannel (gray colors) filled with water (bluish colors).
Experimental and theoretical study of photoluminescence and magnetic properties of metal–organic polymers based on squarate and tetrazolate moieties containing linkers
Authors: Seco Jose M. , Calahorro Antonio J. , Sebastian Eider San , Salinas-Castillo Alfonso , Colacio Enrique , Rodríguez-Diéguez Antonio
Published: October 2015

Cd2+, Zn2+ or Co2+ based luminescence and magnetic properties of isostructural metal organic chains.
Synthesis of magnetic cobalt ferrite nanoparticles with controlled morphology, monodispersity and composition: the influence of solvent, surfactant, reductant and synthetic conditions
Authors: Lu Le T. , Dung Ngo T. , Tung Le D. , Thanh Cao T. , Quy Ong K. , Chuc Nguyen V. , Maenosono Shinya , Thanh Nguyen T. K.
Published: October 2015

Influence of synthetic conditions (e.g., ratio of oleic acid/ oleylamine concentrations, reaction time, solvents and reductants on the formation of high quality CoFe2O4 nanoparticles was comprehensively investigated.
Below-gap excitation of semiconducting single-wall carbon nanotubes
Authors: Soavi G. , Grupp A. , Budweg A. , Scotognella F. , Hefner T. , Hertel T. , Lanzani G. , Leitenstorfer A. , Cerullo G. , Brida D.
Published: October 2015

Unexpectedly, photons with energy well below the lowest exciton lead to linear excitation of electronic states in semiconducting swnts.
Highly sensitive determination of perphenazine on a carbon nanocomposite ionic liquid electrode
Authors: Fasihi Farshid , Farjami Fatemeh , Shafiee Gholam Hossein
Published: October 2015

A multi-walled carbon nanotube–ionic liquid nanocomposite was fabricated for the electrochemical detection of perphenazine, suitable for the analysis of pharmaceuticals and blood serum samples.
Expanding the nuclear forensic toolkit: chemical profiling of uranium ore concentrate particles by synchrotron X-ray microanalysis
Authors: Crean Daniel E. , Corkhill Claire L. , Nicholls Timothy , Tappero Ryan , Collins Jane M. , Hyatt Neil C.
Published: October 2015

Synchrotron microanalysis was used to provide novel advanced characterisation of uranium ore concentrate particles in application to nuclear forensic science.
MCM-41 bound dibenzo-18-crown-6 ether: a recoverable phase-transfer nano catalyst for smooth and regioselective conversion of oxiranes to β-azidohydrins and β-cyanohydrins in water
Authors: Yousefi Sarah , Kiasat Ali Reza
Published: October 2015

A new organic–inorganic hybrid nanocomposite was prepared by immobilizing dibenzo-18-crown-6 onto covalently linked amine functionalized mesoporous MCM-41 via a simple post-synthesis method.
Arginyl-glutamine dipeptide attenuates experimental colitis by enhancing antioxidant function and inhibiting nuclear factor-kappaB
Authors: Yu Hua , Dong Mingjun , Xu Yidong , He Ning , Dai Xiaoyu , Li Keqiang
Published: October 2015

This study aimed to investigate the effect and underlying mechanism of Arginyl-glutamine (AG) dipeptide on dextran sulfate sodium (DSS)-induced colitis byin vivoandin vitromodels.
Ultrasonic preparation of tungsten disulfide single-layers and quantum dots
Authors: Štengl Václav , Tolasz Jakub , Popelková Daniela
Published: October 2015

Natural raw mineral tungstenite (WS2) was exfoliated to single-layer sheets using high intensity ultrasound.
Evaluation of cobalt oxide, copper oxide and their solid solutions as heterogeneous catalysts for Fenton-degradation of dye pollutants
Authors: Shen Yi , Zhang Zhihui , Xiao Kaijun
Published: October 2015

Co0.5Cu0.5O nanoparticles were synthesized via the calcination of corresponding oxalates and showed outstanding catalytic performance for the Fenton-degradation of Congo red.
Alternating total variation and non‐local total variation for fast compressed sensing magnetic resonance imaging
Authors: Hao Wangli , Li Jianwu
Published: October 2015

Total variance‐(TV) based compressed sensing MRI (CS‐MRI) reconstruction methods are effective in restoring a magnetic resonance (MR) image structure from undersampled k‐space data. However, the local details of MR images are usually oversmoothed such that block effects are easily caused. Fortunately, the problem can be overcome by the non‐local total variation (NLTV), which is highly effective in keeping fine details and sharping image edges. Nevertheless, NLTV is not good at finding similar patches. Considering TV and NLTV are complementary, it is proposed to use them alternatively instead of combining them in one objective function for CS‐MRI. In one alternation, the objective function containing the TV and the wavelet regularisations is firstly used to build the structure of the reconstructed MR image through running several iterations of the optimisation method and then the objective function including the NLTV and the wavelet constraints is used to remove the blocking effects and to preserve the image details through running only one iteration of the optimisation method. A number of alternations are run to find the final reconstruction image. Experimental results validate the effectiveness of the method regarding both reconstruction accuracy and computation complexity.
Filter‐and‐forward transceiver design for cognitive two‐way relay networks
Authors: Maleki Marjan , Vakili Vahid Tabataba
Published: October 2015

In this study a new approach to filter‐and‐forward (FF) relay design in an overlay cognitive radio (CR) network with frequency selective channels is proposed. In this system, to implement two‐way relaying scheme, a secondary multi‐antenna node acts as a relay and helps two primary users (PUs) communicate with each other and in return the secondary node superposes its signal to filtered signals of PUs. The authors intend to design secondary transceiver under two criteria, one from the viewpoint of improving the performance of secondary network and the other to guarantee quality of service (QoS) of primary network. The first criterion is to maximise the signal‐to‐interference‐plus‐noise ratio (SINR) of secondary receiver subject to constraints on QoS of PUs and the relay transmitted power. For the other one, the goal is to achieve max‐min fairness among PUs through maximising the worse signal‐to‐interference‐plus‐noise ratio (SINR) of PUs subject to constraints on QoS of secondary receiver and transmit power of relay. The authors employ an alternating optimisation algorithm to find the beamforming matrices and the allocated power to secondary receiver's message in these non‐convex problems. Simulation results show that the proposed FF approach has better performance compared with simple AF relaying strategy.
Suppression of seizures based on the multi-coupled neural mass model
Authors: Cao Yuzhen , Ren Kaili , Su Fei , Deng Bin , Wei Xile , Wang Jiang
Published: October 2015

Epilepsy is one of the most common serious neurological disorders, which affects approximately 1% of population in the world. In order to effectively control the seizures, we propose a novel control methodology, which combines the feedback linearization control (FLC) with the underlying mechanism of epilepsy, to achieve the suppression of seizures. The three coupled neural mass model is constructed to study the property of the electroencephalographs (EEGs). Meanwhile, with the model we research on the propagation of epileptiform waves and the synchronization of populations, which are taken as the foundation of our control method. Results show that the proposed approach not only yields excellent performances in clamping the pathological spiking patterns to the reference signals derived under the normal state but also achieves the normalization of the pathological parameter, where the parameters are estimated from EEGs with Unscented Kalman Filter. The specific contribution of this paper is to treat the epilepsy from its pathogenesis with the FLC, which provides critical theoretical basis for the clinical treatment of neurological disorders.
A temperature oscillation instrument to determine pyroelectric properties of materials at low frequencies: Towards elimination of lock-in methods
Authors: Khanbareh H. , Schelen J. B. J. , van der Zwaag S. , Groen W. A.
Published: October 2015

Pyroelectric properties of materials can be accurately determined by applying a new digital signal processing method on the discrete sampled data obtained with a temperature oscillation technique. The pyroelectric coefficient is calculated from the component of the generated current 90∘ out of phase with respect to the sinusoidal temperature wave. The novelty of the proposed approach lies in the signal analysis procedure which implements a simple Fast Fourier transform that filters residual noise through convolution, and calculates the phase difference between the peaks of the temperature and current waves. The new idea requires relatively simple hardware and enables very accurate measurement of the pyroelectric coefficient of materials at ultra low frequencies, 1–250 mHz, without using costly lock-in amplifiers.
A simple transferable adaptive potential to study phase separation in large-scale xMgO-(1-x)SiO2 binary glasses
Authors: Bidault Xavier , Chaussedent Stéphane , Blanc Wilfried
Published: October 2015

A simple transferable adaptive model is developed and it allows for the first time to simulate by molecular dynamics the separation of large phases in the MgO-SiO2 binary system, as experimentally observed and as predicted by the phase diagram, meaning that separated phases have various compositions. This is a real improvement over fixed-charge models, which are often limited to an interpretation involving the formation of pure clusters, or involving the modified random network model. Our adaptive model, efficient to reproduce known crystalline and glassy structures, allows us to track the formation of large amorphous Mg-rich Si-poor nanoparticles in an Mg-poor Si-rich matrix from a 0.1MgO-0.9SiO2 melt.
Maximal energy extraction under discrete diffusive exchange
Authors: Hay M. J. , Schiff J. , Fisch N. J.
Published: October 2015

Waves propagating through a bounded plasma can rearrange the densities of states in the six-dimensional velocity-configuration phase space. Depending on the rearrangement, the wave energy can either increase or decrease, with the difference taken up by the total plasma energy. In the case where the rearrangement is diffusive, only certain plasma states can be reached. It turns out that the set of reachable states through such diffusive rearrangements has been described in very different contexts. Building upon those descriptions, and making use of the fact that the plasma energy is a linear functional of the state densities, the maximal extractable energy under diffusive rearrangement can then be addressed through linear programming.
Precession of cylindrical dust particles in the plasma sheath
Authors: Banu N. , Ticoş C. M.
Published: October 2015

The vertical precession of cylindrical dust particles levitated in the sheath of an rf plasma is experimentally investigated. Typically, the dust particles have two equilibrium positions depending on the orientation of their longitudinal axis: horizontal and vertical. A transition between these two states is induced by rapidly increasing the neutral gas pressure in the plasma chamber. During this transition, the cylindrical dust particles make an angle with the horizontal and rotate about their center of mass. The rotation speed increases as the dust rods aligned with the vertical axis. All dust particles will eventually end up in the vertical state while spinning fast about their longitudinal axis. Dust-dust interaction and the attracting ion wakes are possible mechanisms for inducing the observed dust precession.
Coarse-grained molecular dynamics study of membrane fusion: Curvature effects on free energy barriers along the stalk mechanism
Authors: Kawamoto Shuhei , Klein Michael L. , Shinoda Wataru
Published: October 2015

The effects of membrane curvature on the free energy barrier for membrane fusion have been investigated using coarse-grained molecular dynamics (CG-MD) simulations, assuming that fusion takes place through a stalk intermediate. Free energy barriers were estimated for stalk formation as well as for fusion pore formation using the guiding potential method. Specifically, the three different geometries of two apposed membranes were considered: vesicle–vesicle, vesicle–planar, and planar–planar membranes. The free energy barriers for the resulting fusion were found to depend importantly on the fusing membrane geometries; the lowest barrier was obtained for vesicular membranes. Further, lipid sorting was observed in fusion of the mixed membranes of dimyristoyl phosphatidylcholine and dioleoyl phosphatidylethanolamine (DOPE). Specifically, DOPE molecules were found to assemble around the stalk to support the highly negative curved membrane surface. A consistent result for lipid sorting was observed when a simple continuum model (CM) was used, where the Helfrich energy and mixing entropy of the lipids were taken into account. However, the CM predicts a much higher free energy barrier than found using CG-MD. This discrepancy originates from the conformational changes of lipids, which were not considered in the CM. The results of the CG-MD simulations reveal that a large conformational change in the lipid takes place around the stalk region, which results in a reduction of free energy barriers along the stalk mechanism of membrane fusion.
Gaussian process model for extrapolation of scattering observables for complex molecules: From benzene to benzonitrile
Authors: Cui Jie , Li Zhiying , Krems Roman V.
Published: October 2015

We consider a problem of extrapolating the collision properties of a large polyatomic molecule A–H to make predictions of the dynamical properties for another molecule related to A–H by the substitution of the H atom with a small molecular group X, without explicitly computing the potential energy surface for A–X. We assume that the effect of the −H →−X substitution is embodied in a multidimensional function with unknown parameters characterizing the change of the potential energy surface. We propose to apply the Gaussian Process model to determine the dependence of the dynamical observables on the unknown parameters. This can be used to produce an interval of the observable values which corresponds to physical variations of the potential parameters. We show that the Gaussian Process model combined with classical trajectory calculations can be used to obtain the dependence of the cross sections for collisions of C6H5CN with He on the unknown parameters describing the interaction of the He atom with the CN fragment of the molecule. The unknown parameters are then varied within physically reasonable ranges to produce a prediction uncertainty of the cross sections. The results are normalized to the cross sections for He — C6H6 collisions obtained from quantum scattering calculations in order to provide a prediction interval of the thermally averaged cross sections for collisions of C6H5CN with He.
Dietary fibre and crude protein: impact on gastrointestinal microbial fermentation characteristics and host response
Authors: Pieper R. , Vahjen W. , Zentek J.
Published: October 2015

The role of the gastrointestinal tract microbiota in animal health and nutrition has become the subject of intensive research. Carbohydrates and crude protein are major components of swine diets and numerous studies have been performed looking at the effect of inclusion of dietary fibre with possible functional properties. In recent years, our understanding of the diversity and functionality of the gastrointestinal tract microbiota has increased further enabling the possibility for their targeted modulation. However, favouring potential beneficial bacteria, inhibiting possible pathogens or promotion of the formation of desired metabolites, is complex and underlies many factors and uncertainties. Approaches targeting this complex ecosystem (and discussed in this review) include the utilisation of fermentable carbohydrates such as resistant starch, cereal 1–3/1–4 β-glucans, arabinoxylans, inulin or other sources from legumes and industrial by-products. In addition, strategies regarding protein level and the protein : carbohydrate ratio are discussed briefly. Results are both promising and sometimes rather disillusioning considering the dietary concentrations needed to show biologically relevant effects. Deriving recommendations for an optimal inclusion rate of dietary fibre for weaning, growing pigs and sows and maximum levels for dietary crude protein may be one of the main challenges in the near future in the swine industry.
Determination of cupric ion concentrations in marine waters: an improved procedure and comparison with other speciation methods
Authors: Tait Tara N. , Rabson Lisa M. , Diamond Rachael L. , Cooper Christopher A. , McGeer James C. , Smith D. Scott
Published: October 2015

Environmental context A Cu ion-selective electrode is potentially an excellent tool for cupric ion measurements in salt water, but it is prone to poor reproducibility. We show that dramatic improvements can be obtained by using a Cu ion-selective electrode and a one-point calibration method that corrects for electrode fouling. The method shows promise to be used to collect data on toxic cupric ion concentrations in saltwater environments. Abstract Free Cu is often used as an indicator for potential Cu toxicity. Free ionic Cu2+ was measured using a flow-through ion-selective electrode (ISE). Four different marine samples were collected from various locations and analysed during a fixed-pH Cu titration using an external standard calibration ISE method. Free cupric determinations in the range 10–12 to 10–7molL–1 were consistent with published literature but replicate measures showed up to four orders of magnitude variability. To improve reproducibility, an internal calibration method was developed. The new method was validated using artificial seawater with added tryptophan as the model ligand. The free Cu measured using the improved method showed the same trends as the external calibration data but reproducibility increased to an order of magnitude or better. The potential applicability of this new method was also highlighted in that it matches, in the environmentally and regulatory significant range of total Cu, with a fluorescence quenching method applied to one of the four samples. The ISE data do not agree with free ion concentrations estimated from anodic stripping voltammetry (ASV) though. This suggests that, at least for these samples, ASV responded to a larger fraction of total Cu than simply the inorganic complexes. Caution should be exercised when using ASV as a proxy for bioavailability because the trends in ASV-derived free Cu did not match the free Cu as estimated by ISE. This ability to more reliably measure free Cu is significant for predicting and measuring toxicity on Cu exposure.
Continuous solutions of nonlinear Cauchy-Riemann equations and pseudoholomorphic curves in normal coordinates
Authors: Coffman Adam , Pan Yifei , Zhang Yuan
Published: October 2015

We establish elliptic regularity for nonlinear, inhomogeneous Cauchy-Riemann equations under weak assumptions, and give a counterexample in a borderline case. In some cases where the inhomogeneous term has a separable factorization, the solution set can be explicitly calculated. The methods also give local parametric formulas for pseudoholomorphic curves with respect to some continuous almost complex structures.
Conflict and cooperation in eukaryogenesis: implications for the timing of endosymbiosis and the evolution of sex
Authors: Radzvilavicius Arunas L. , Blackstone Neil W.
Published: October 2015

Roughly 1.5–2.0 Gya, the eukaryotic cell evolved from an endosymbiosis of an archaeal host and proteobacterial symbionts. The timing of this endosymbiosis relative to the evolution of eukaryotic features remains subject to considerable debate, yet the evolutionary process itself constrains the timing of these events. Endosymbiosis entailed levels-of-selection conflicts, and mechanisms of conflict mediation had to evolve for eukaryogenesis to proceed. The initial mechanisms of conflict mediation (e.g. signalling with calcium and soluble adenylyl cyclase, substrate carriers, adenine nucleotide translocase, uncouplers) led to metabolic homeostasis in the eukaryotic cell. Later mechanisms (e.g. mitochondrial gene loss) contributed to the chimeric eukaryotic genome. These integral features of eukaryotes were derived because of, and therefore subsequent to, endosymbiosis. Perhaps the greatest opportunity for conflict arose with the emergence of eukaryotic sex, involving whole-cell fusion. A simple model demonstrates that competition on the lower level severely hinders the evolution of sex. Cytoplasmic mixing, however, is beneficial for non-cooperative endosymbionts, which could have used their aerobic metabolism to manipulate the life history of the host. While early evolution of sex may have facilitated symbiont acquisition, sex would have also destabilized the subsequent endosymbiosis. More plausibly, the evolution of sex and the true nucleus concluded the transition.
Exposure to sub-inhibitory concentrations of cefotaxime enhances the systemic colonization of
Salmonella
Typhimurium in BALB/c mice
Authors: Molina-Quiroz Roberto C. , Silva Cecilia A. , Molina Cristian F. , Leiva Lorenzo E. , Reyes-Cerpa Sebastián , Contreras Inés , Santiviago Carlos A.
Published: October 2015

It has been proposed that sub-inhibitory concentrations of antibiotics play a role in virulence modulation. In this study, we evaluated the ability of
Salmonella enterica
serovar Typhimurium (hereafter
S
. Typhimurium) to colonize systemically BALB/c mice after exposure to a sub-inhibitory concentration of cefotaxime (CTX).
In vivo
competition assays showed a fivefold increase in systemic colonization of CTX-exposed bacteria when compared to untreated bacteria. To identify the molecular mechanisms involved in this phenomenon, we carried out a high-throughput genetic screen. A transposon library of
S
. Typhimurium mutants was subjected to negative selection in the presence of a sub-inhibitory concentration of CTX and genes related to anaerobic metabolism, biosynthesis of purines, pyrimidines, amino acids and other metabolites were identified as needed to survive in this condition. In addition, an impaired ability for oxygen consumption was observed when bacteria were cultured in the presence of a sub-inhibitory concentration of CTX. Altogether, our data indicate that exposure to sub-lethal concentrations of CTX increases the systemic colonization of
S.
Typhimurium in BALB/c mice in part by the establishment of a fitness alteration conducive to anaerobic metabolism.
Parasite and predator risk assessment: nuanced use of olfactory cues
Authors: Sharp John G. , Garnick Sarah , Elgar Mark A. , Coulson Graeme
Published: October 2015

Foraging herbivores face twin threats of predation and parasite infection, but the risk of predation has received much more attention. We evaluated, experimentally, the role of olfactory cues in predator and parasite risk assessment on the foraging behaviour of a population of marked, free-ranging, red-necked wallabies (
Macropus rufogriseus
). The wallabies adjusted their behaviour according to these olfactory cues. They foraged less, were more vigilant and spent less time at feeders placed in the vicinity of faeces from dogs that had consumed wallaby or kangaroo meat compared with that of dogs feeding on sheep, rabbit or possum meat. Wallabies also showed a species-specific faecal aversion by consuming less food from feeders contaminated with wallaby faeces compared with sympatric kangaroo faeces, whose gastrointestinal parasite fauna differs from that of the wallabies. Combining both parasite and predation cues in a single field experiment revealed that these risks had an additive effect, rather than the wallabies compromising their response to one risk at the expense of the other.
Rapid three dimensional two photon neural population scanning
Authors: Schuck Renaud , Quicke Peter , Copeland Caroline , Garasto Stefania , Annecchino Luca A. , Hwang June Kyu , Schultz Simon R. ,   EMBS Member
Published: October 2015

Recording the activity of neural populations at high sampling rates is a fundamental requirement for understanding computation in neural circuits. Two photon microscopy provides one promising approach towards this. However, neural circuits are three dimensional, and functional imaging in two dimensions fails to capture the 3D nature of neural dynamics. Electrically tunable lenses (ETLs) provide a simple and cheap method to extend laser scanning microscopy into the relatively unexploited third dimension. We have therefore incorporated them into our Adaptive Spiral Scanning (SSA) algorithm, which calculates kinematically efficient scanning strategies using radially modulated spiral paths. We characterised the response of the ETL, incorporated its dynamics using MATLAB models of the SSA algorithm and tested the models on populations of Izhikevich neurons of varying size and density. From this, we show that our algorithms can theoretically at least achieve sampling rates of 36.2Hz compared to 21.6Hz previously reported for 3D scanning techniques.
Osmophoresis – a possible mechanism for vesicle trafficking in tip-growing cells
Authors: Lipchinsky Andrei
Published: October 2015

A mechanism for polarized transport of vesicles by means of osmotic propulsions is proposed and substantiated for tip-growing cells. An analysis is presented which shows that in pollen tubes the gradient of cytosolic water potential can drive vesicle movement either in the anterograde or retrograde direction, depending on the vesicle position, its radius and the phase of growth oscillation. The importance of transcellular water flow for cytoskeletal dynamics and cell motility is highlighted.
Supply risk management and competitive advantage: a misfit model
Authors: Gualandris Jury , Kalchschmidt Matteo
Published: October 2015

Purpose

– The purpose of this paper is to develop a model of congruence for the management of supply risk that is easy to apply, but also accurate. The authors also aim at providing empirical evidence about the relationship between misfit – i.e. the incongruence between a firm’s preparedness in (supply) risk management and the potential riskiness characterising the context – and competitive advantage.

Design/methodology/approach

– In line with the purpose, literature and field interviews were used to develop a model of congruence in the context of supply risk management (SRM) and operationalise it within a questionnaire. Then, the authors collected survey data to validate the model.

Findings

– Results show that competitive advantage decreases when the firm’s preparedness in SRM does not match to the pattern of risk conditions (i.e. environmental vulnerabilities).

Research limitations/implications

– The model of congruence here developed is simple to apply but offer effective decisions support. This study, thus, stimulates future research on the assessment and management of supply chain risk. This study, also, fosters the attention to the non-linear relationship between risk management and business performance.

Practical implications

– This study develops a model that can be used by practitioners to configure an optimal adoption of SRM practices. Also, the analysis allows to draw some specific recommendations for supply chain managers aiming at improving their preparedness in SRM.

Originality/value

– By relying on SRM literature, the balanced-resilience logic and the theoretical framework of contingency theory, this study develops and test a model of congruence that shows how companies can gain competitive advantage through the management of supply risk.
Creating fen initiation conditions: a new approach for peatland reclamation in the oil sands region of Alberta
Authors: Borkenhagen Andrea , Cooper David J.
Published: October 2015

Reclaiming peatland ecosystems is challenging our understanding of how to rebuild functioning landscapes. Assisted succession may provide a practical approach to guide the reestablishment of peatlands in denuded landscapes. In Alberta, the majority of peatlands began as fens during the paludification process. This research focuses on creating fen initiation conditions to establish fen moss species on mineral sediment as an approach for peatland reclamation in the oil sands region.

In a field mesocosm experiment, we evaluated the establishment of five common fen mosses (Drepanocladus aduncus, Ptychostomum (Bryum) pseudotriquetrum, Campylium stellatum, Tomentypnum nitens and Aulacomnium palustre) introduced in equal proportions to clay loam. To determine the optimal hydrologic conditions for the establishment of each species, we tested four water levels (0, −10, −20 and −30 cm). We created vegetation types similar to those identified at the peat–mineral interface in peat profiles to determine the effect of herbaceous plant, low shrub and wood‐strand mulch cover treatments on moss establishment.

Three seasons after introduction, total moss cover averaged 40% and was greatest under all cover treatments and at the 0 cm water level. Total moss biomass averaged 95·5 g m−2 in moss introduction mesocosms and was greatest under low shrubs and herbaceous plants and at the 0 and −30 cm water levels. Fen moss species distribution was significantly influenced by water‐table depth. Drepanocladus aduncus and Ptychostomum pseudotriquetrum were most common at 0 cm and Aulacomnium palustre and Tomentypnum nitens at −30 cm.

In this approach, we created vegetation types similar to those found on mineral sediments at the base of Alberta peat cores and successfully established distinct fen moss communities along a water‐table gradient and under shade cover. Introducing a suite of fen moss species that inhabit a range of hydrologic niches under low shrubs or herbaceous plants improves moss establishment.

Synthesis and applications. Our research shows that it is possible to create fen initiation conditions on clay loam sediment by introducing foundation moss and vascular plant species at optimal water levels. Restoring the community structure and biomass accumulation that occurs in the initial stages of fen development appears to be a suitable target for peatland reclamation. These methods introduce a practical strategy to reclaim peatlands in the heavily impacted oil sands region of Alberta.
REVIEW: A mechanistic framework to improve understanding and applications of push‐pull systems in pest management
Authors: Eigenbrode Sanford D. , Birch A. Nicholas E. , Lindzey Summer , Meadow Richard , Snyder William E.
Published: October 2015

Push‐pull or stimulo‐deterrent cropping systems combine a trap crop or other attractant or arrestant stimulus distant from the crop and a deterrent or repellent near or within the target crop, to divert pests, reducing their populations on the target crop. Although the concept is decades old, there are few successful applications in pest management.

In this article, we address this shortcoming by offering a mechanistic conceptual framework of push‐pull systems, based on the cues, sensory modalities, pest behaviours and spatial ranges over which they can occur during host selection and that can influence pest distribution.

We review published work on push‐pull systems in the light of this framework, finding that the literature tends to focus on longer‐range stimulo‐deterrence strategies rather than the full range of cues involved and modalities that can come into play, with imperfect understanding of cues involved in most systems.

The imbalance in research emphasis and incomplete understanding of push‐pull mechanisms suggest opportunities to improve and broaden the palette of potential push‐pull technologies.

The framework also helps clarify other aspects important for achieving success with push‐pull methods, including the role of synergy, deployment geometry, intraspecific variability and the wider arthropod community in these systems.

Synthesis and applications. A conceptual and mechanistic framework is provided for the development of push‐pull or stimulo‐deterrent pest management approaches. This framework informs a proposed research agenda for designing push‐pull technologies. That agenda involves including all cues and modalities, exploiting synergies, tuning deployment geometry in accordance with these factors. It also considers pest and crop dynamics and the arthropod community of the system. The framework can benefit managers by helping them to consider more fully the behaviour of the target pests when creating crop and non‐crop geometries to achieve push‐pull benefits. Research‐based push‐pull systems will be better implemented and modified by producers if they understand how insects respond to sources of push and pull in the system, allowing effective monitoring and fine‐tuning to increase effectiveness of this specialized component of integrated pest management.