bluuebunny/crossref_metadata_2025 huggingface dataset:
Bilinear normal mixing model for spectral unmixing
Authors: Luo Wenfei , Gao Lianru , Zhang Ruihao , Marinoni Andrea , Zhang Bing
Published: September 2018

Spectral unmixing (SU) is a useful tool for hyperspectral remote sensing image analysis. However, due to the interference of spectral variance and non‐linearity caused by photon multiple‐scattering, the result might be an inaccuracy. In addition, the unmixing performance of typically relies on the prior knowledge of endmembers. Although many classical endmember extraction algorithms have been presented, it is hard to obtain accurate endmembers in practical applications. This study presents a bilinear normal mixing model named as BNMM to tackle these issues. In fact, BNMM employs the polynomial post‐non‐linear mixing model to alleviate the effect of non‐linearity and uses a normal distribution model to reduce the influence of endmembers variability. Based on the BNMM, the authors develop a Hamiltonian Monte Carlo algorithm for SU. The experimental results demonstrate that the proposed algorithm outperforms other classical unmixing algorithms in the case of simulated and benchmark datasets.
Coupling between coils in the presence of conducting medium
Authors: Vallecchi Andrea , Chu Son , Solymar Laszlo , Stevens Christopher J. , Shamonina Ekaterina
Published: September 2018

The authors have studied analytically by simulation and by experiment the impact of a conducting medium on the mutual inductance between two coils, in particular as related to the attenuation of magneto‐inductive (MI) waves. To illustrate the physics, the distributions of both the magnetic field and the Poynting vector are determined. They show that the plane wave approach used in the literature for the theoretical description of MI attenuation has only limited validity. It is further found that the mutual inductance becomes a complex quantity, its modulus declining monotonically as a function of conductivity or medium thickness. Their results will be relevant for the design and optimisation of MI waveguide links in conducting media, in general, and particularly when the attenuation is caused by soil conductivity. The results can also be useful for practical applications including in vivo communication and wireless power transfer for medical implants.
Radar cross‐section of pedestrians in the low‐THz band
Authors: Marchetti Emidio , Du Rui , Willetts Ben , Norouzian Fatemeh , Hoare Edward G. , Tran Thuy Yung , Clarke Nigel , Cherniakov Mikhail , Gashinova Marina
Published: September 2018

Low‐terahertz (THz) (above 150 GHz) radar sensing is one of the promising technologies to provide safe navigation for autonomous cars due to its expected high‐resolution imaging capability. It is anticipated that for robust operation at high levels of autonomy the sensor suite should provide a fusion of video and radar data and its efficiency depends on radar ability to deliver a resolution high enough to be compatible with that of the optical image. Performance of low‐THz radar, capable to deliver required resolution, is considered in this study, with the focus on reflectivities of pedestrians at frequencies within the low‐THz region – 150 and 300 GHz. Backscatter returns are collected in a controlled environment at a number of frequency bands and at different aspect angles. Measurement methodology is presented and several indicators of reflectivities are calculated. Results are compared with values of radar cross‐section reported for current automotive frequency standards 24 and 77 GHz. The effect of clothing on reflectivities is also considered in this study.
Galaxy and Mass Assembly (GAMA): Accurate number densities and environments of massive ultra-compact galaxies at 0.02 < z < 0.3
Authors: Buitrago F. , Ferreras I. , Kelvin L. S. , Baldry I. K. , Davies L. , Angthopo J. , Khochfar S. , Hopkins A. M. , Driver S. P. , Brough S. , Sabater J. , Conselice C. J. , Liske J. , Holwerda B. W. , Bremer M. N. , Phillipps S. , López-Sánchez Á. R. , Graham A. W.
Published: September 2018

Context. Massive ultra-compact galaxies (MUGs) are common at z = 2−3, but very rare in the nearby Universe. Simulations predict that the few surviving MUGs should reside in galaxy clusters, whose large relative velocities prevent them from merging, thus maintaining their original properties (namely stellar populations, masses, sizes and dynamical state).

Aims. Our goal is to obtain a complete census of the MUG population at 0.02 < z < 0.3, determining the number density, population properties and environment.

Methods. We have taken advantage of the high-completeness, large-area spectroscopic GAMA survey, complementing it with deeper imaging from the KiDS and VIKING surveys. We find a set of 22 bona-fide MUGs, defined as having high stellar mass (> 8 × 1010 M⊙) and compact size (Re < 2 kpc). An additional set of seven lower-mass objects (6 × 1010 < M⋆/M⊙ < 8 × 1010) are also potential candidates according to typical mass uncertainties.

Results. The comoving number density of MUGs at low redshift (z < 0.3) is constrained at (1.0 ± 0.4)×10−6 Mpc−3, consistent with galaxy evolution models. However, we find a mixed distribution of old and young galaxies, with a quarter of the sample representing (old) relics. MUGs have a predominantly early or swollen disk morphology (Sérsic index 1 < n < 2.5) with high stellar surface densities (⟨Σe⟩∼1010 M⊙ Kpc−2). Interestingly, a large fraction feature close companions – at least in projection – suggesting that many (but not all) reside in the central regions of groups. Halo masses show these galaxies inhabit average-mass groups.

Conclusions. As MUGs are found to be almost equally distributed among environments of different masses, their relative fraction is higher in more massive overdensities, matching the expectations that some of these galaxies fell in these regions at early times. However, there must be another channel leading some of these galaxies to an abnormally low merger history because our sample shows a number of objects that do not inhabit particularly dense environments.
Application of selected methods of digital simulation to analyse dynamic impact of driven pneumatic wheel on soil in agrotechnical treatments and forestry to limit negative impact on the environment
Authors: Malesa Włodzimierz
Published: September 2018

Loads transmitted by mechanical vehicles to soil result in its deformation and compaction. Increasingly bigger and more efficient machines affect the base they move on to a significantly greater extent. The purpose of this study with the use of digital simulation is to reduce expenses on costly experimental studies with the use of off-road vehicles or specially developed laboratory machines. The simulations were conducted using the Mechanical Event Simulation module, which is a part of the Autodesk Simulation Mechanical software. For each step, the simulation program provides the value of stress in all nodes of the base grid. The stress values obtained via dynamic simulations are consistent with the values registered under laboratory conditions. When classical experiments are replaced with numerical methods, not only the cost is reduced, but also the impact of weather conditions on measurement results is avoided and the time required for the study is shortened. The use of the described methods allows for design and selection parameters of exploitation pneumatics drive mechanism, which will significantly reduce the negative impact on the natural environment by machines in agrotechnical treatments and forestry. This is related to the environmental protection issues.
Coal combustion modelling in a frontal pulverized coal-fired boiler
Authors: Madejski Paweł
Published: September 2018

The paper presents results of numerical modelling of pulverized coal combustion process in the coal-fired boiler. In the numerical model, coal combustion process includes particle heating, devolatilization, char combustion, as well as turbulent flow and radiative heat transfer was modelled. Presented modelling results were carried out using the Open Source CFD code - Code_Saturne created and developed by EDF R&D and were used to study the combustion of coal in power plant boiler with the objective of simulating the operational conditions and identifying factors of inefficiency. The behaviour of the flow of air and pulverized coal through the burners was modelled, and the three-dimensional flue gas flow through the combustion chamber and heat exchangers was reproduced in the simulation.
Economical and technical aspects of using air heat pumps for hot water
Authors: Szreder Mariusz
Published: September 2018

The paper presents selected technical and economic aspects related to the use of air heat pumps for the preparation of domestic hot water DHW. The research shows that heating the water in the 130 dm3 storage tank with the A21/W30-50 profile lasted an average of 130 minutes, and the heat pump consumed about 2.2 kWh of energy per one heating cycle. Heating water in a 130 dm3 storage tank from 25°C to 40°C lasted an average of 60 minutes, while heating water for another 5°C took 30 minutes. The operation of the heat pump in the higher temperature of the water in the storage tank is less effective, making the heating of water in the tank above 50°C is ineffective.
Energy efficiency of ground-air heat exchanger in the ventilation and airconditioning systems
Authors: Łuczak Rafał , Ptaszyński Bogusław , Kuczera Zbigniew , Życzkowski Piotr
Published: September 2018

In the article, analysis of heat exchangers, working together with air-conditioning system, are presented. For an object with known requirement to hot and cold, air heat exchanger (ground type) is designed. For that defined system, the energy analysis of heat exchanger’s energy work in yearly cycle, including a work of air treatment with full (cooling - desiccation and heating of air in the summer, heating and moisturizing in the winter) and not quite full (cooling of air in the summer, heating of air in the winter) air-conditioning are examined. Effects connected with a reduction of energy costs needed for heat treatment of air blown to the room are specified included the climatic conditions like air heating and cooling degree-hours.
Experiment designing in operating investigations of subassembly of the marine energy systems
Authors: Monieta Jan
Published: September 2018

To choose the receive locations of diagnostic signals, reliability and preliminary investigations were applied. The functional systems and the most unreliable subassemblies were determined. The studies were conducted for the auxiliary marine engines with the same rated speed and fueled with same distillation and residual fuels. In the article a choice of the ship's object, which has a significant impact on reliability, operating costs and the functions performed, is presented. Reliability, economic and risk of exploitation investigations were carried out, which allowed selecting the facility with the highest failure, costs of adverse events and threat to the natural environment. The research covered the objects of a ship owner operating mainly bulk cargo vessels for mass transport and their essential assemblies - combustion engines.In order to obtain a reasonable amount of information on the state of the examined combustion engine, the following experimental planning methods were used: experiment type, essential elements, location of measurement sensors, measured quantities, test conditions, measurement frequencies, measurement data analysis and inference methods, etc.The reliability indicators and preliminary diagnostic tests were used to select the diagnostic signal reception points. Functional systems and the most unreliable subassemblies were defined in this way. The tests were carried out for auxiliary marine engines with the same rotational speed and fueled by distillation and residual fuels. The tests were conducted for several types of combustion engines.
Modernity and ecology in the aspect of a packaging industry company management
Authors: Ociepka-Kubicka Agnieszka
Published: September 2018

The article discusses the issue of innovativeness in the area of packaging with reference to the balanced development. It also presents the threats of the packaging industry to the natural environment and the methods and tools of their restriction. The importance of biodegradable packaging and packaging from recycled materials is stressed. Moreover, the problems of the burdensomeness of packaging products and the packaging manufacturers are emphasised. Modern enterprises must implement pro-ecological, innovative activities, both at the level of production and the company’s management. The changing economic conditions and the social pressure result in the new company’s management goals - alongside the production, financial and other aspects. These new goals refer to the widely understood environment, and human life and health. The analysis of the innovative and pro-ecological activities implementation was presented on the example of a modern, dynamically developing joint stock company, United Packaging S.A., producing packaging from corrugated board with the increased water resistance for food industry, household chemicals and electronic industry.
Numerical modeling of airflow over column of vehicles using Ansys® package
Authors: Hamiga Władysław , Ciesielka Wojciech
Published: September 2018

Growing needs in transportation determinate systems development which improve efficiency of travel and reduce harmful influence to environment. Computational Fluid Dynamic (CFD) uses numerical analysis to find optimal solutions in terms of chosen objective function. Time save and reduce costs for experiments on prototypes are one of the advantages of this method. The aim of this research is to analyze airflow around different motor vehicles which are moving together in the same direction. To reduce fuel consumption and, at the same time, decrease negative influence to environment, the primary target was reducing total drag force during a ride. The vehicles were set in a column - one after another. In this work considered three types of vehicles: Car, Van and a Truck. Presented vehicles were organized into appropriate groups, creating different configuration. Additional parameter in simulation was distance between vehicles. Simulations of singular vehicles were also done. It allows to evaluate influence of moving vehicles in a column for generated drag force. Described traffic situation were modeled and numerically calculated using ANSYS® package. The purpose of this work was to assess the impact of the distance between vehicles, in a given configuration, for generated drag force.
The impact of the condensation process on the degree of cleaning of flue gases from acidic compounds
Authors: Szulc Piotr , Tietze Tomasz , Smykowski Daniel
Published: September 2018

The paper presents studies on the impact of the process of condensation of water vapour on the process of cleaning of flue gases from acidic compounds. The measurements were carried out on a pilot-scale plant for waste heat recovery from flue gases, taking into account the process of condensation of the water vapour contained in them. The plant was connected to a lignite-fired power unit with a capacity of 360 MW located at PGE GiEK S.A., Bełchatów Power Plant Branch. The impact of the condensation of water vapour on the reduction of sulphur, chlorine and fluorine forming acidic compounds was examined. The studies show that the condensation process is conducive to removal of acidic compounds from flue gases.
Heat kernels and Green functions of sub-Laplacians on Heisenberg groups with multi-dimensional center
Authors: Molahajloo Shahla , Wong M.W.
Published: September 2018

We compute the sub-Laplacian on the Heisenberg group with multi-dimensional center. By taking the inverse Fourier transform with respect to the center, we get the parametrized twisted Laplacians. Then by means of the special Hermite functions, we find the eigenfunctions and the eigenvalues of the twisted Laplacians. The explicit formulas for the heat kernels and Green functions of the twisted Laplacians can then be obtained. Then we give an explicit formula for the heat kernal and Green function of the sub-Laplacian on the Heisenberg group with multi-dimensional center.
Leitbild ärztlicher Homöopathie für den DZVhÄ
Authors:   Deutscher Zentralverein homöopathischer Ärzte
Published: September 2018

Die Homöopathie wurde vor mehr als 200 Jahren von dem deutschen Arzt Dr. Samuel Hahnemann als medizinisches Behandlungskonzept formuliert. Sie beruht auf dem Ähnlichkeitsprinzip – „Ähnliches werde durch Ähnliches behandelt“ –, das seit dem Altertum von Ärzten
1
und Philosophen anerkannt ist. Hahnemann erkannte die Universalität dieses Prinzips und machte sie zur Grundlage eines umfassenden Systems der Medizin mit einer eigenständigen Vorstellung von Gesundheit und Krankheit. Die sich aus der europäischen Medizin herausgebildete Homöopathie wird heutzutage in mehr als 70 Ländern weltweit praktiziert.
Treatment of Long Bone Fractures in Calves with Ilizarov External Fixator
Authors: Sarierler Murat , Gülaydin Ali
Published: September 2018

In this study, the advantages and disadvantages of Ilizarov external fixator in the treatment of long bone fractures in calves were investigated. For this purpose, 26 calves of different breeds, ages and genders, having metacarpal (n = 12), metatarsal (n = 5) and antebrachial (n = 9) fractures underwent surgery under general anaesthesia. Frames, which were prepared before surgery in accordance with the radiographic findings, were applied under open reduction in 18 cases, and under closed reduction in eight cases. In the postoperative period, all calves except one started to bear some weigh on the injured limb on the first day, while the remaining calf did the same on the second day. The consolidation started in the first 2 weeks for 24 of the calves and was completed by the day 55. In the two remaining cases, it started in the third week and was completed on day 71 and day 90, respectively.

The soft tissue wounds were completely healed in all calves and no complications occurred. In five calves that were not kept in our clinic pin tract infections formed. They were controlled rapidly, and there was no change in the fracture reduction or healing duration.

In conclusion, in our study, the Ilizarov external fixator system was applied to long bone fractures in cattle calves, in cases where the fragments were not large enough to apply pins and plates, and which became open and infected after defective bandage practices or unsuitable treatment. Fractures completely healed in all cases, without any complications. These results show that many of the long bone fractures experienced by calves, that were considered for amputation due to the anticipated inability to treat them successfully, could be treated with the use of the Ilizarov system.
Prevalence of Mental Disorders, Health-related Quality of Life, and Service Utilization across the Adult Life Span
Authors: Jacobi F. , Groß J.
Published: September 2018

Mental disorders are widely common and are associated with various costs, both for the individual and for society. DEGS1-MH is the mental-health module of the German Health Interview and Examination Survey (DEGS1) and offers representative data on mental health in Germany. The present paper presents data on 12-month prevalence of mental disorders according to DSM-IV-TR, mental and physical health-related quality of life, and self-reported service utilization due to mental health problems across the adult life span (age 18-79 in six age groups). With 37.7%, young adults (age 18-29) show the highest 12-month prevalence and lowest self-reported mental health-related quality of life. In contrast, the group of older adults (age 60-79) show the lowest 12-month prevalence (19.7%) and report highest mental health-related quality of life. In subjects with mental disorders, physical health-related quality of life is impaired as well, however, particularly in older age groups. Both young and older adults with a 12-month diagnosis use health-related service due to mental problems only very rarely.
Pharmakotherapie im Alter
Authors: Hefner G. , Hiemke C.
Published: September 2018

Bei Alterspatienten bestimmen nicht nur altersbedingte normale pharmakokinetische und pharmakodynamische Veränderungen, sondern auch Faktoren wie Lebensgewohnheiten oder chronische Erkrankungen die unterschiedliche Wirksamkeit und Verträglichkeit von Arzneimitteln im Vergleich zu jüngeren Patienten. Darüber hinaus sind Alterspatienten, insbesondere bei Komorbidität, von den meisten klinischen Studien ausgeschlossen. Daher gibt es nur beschränkte Evidenz für die Wirksamkeit vieler Medikamente. Die mangelhafte Evidenz und die große Variabilität der Pharmakokinetik und Pharmakodynamik erfordern im Alter eine individualisierte Pharmakotherapie. Zur Risikominimierung gilt es, inadäquate Medikamente, übermäßige Polypharmazie, unerwünschte Arzneimittelwechselwirkungen, aber auch eine medikamentöse Unterversorgung zu vermeiden. Das Dictum für Alterspatienten „Start low, go slow“ bezüglich Arzneimitteldosis sollte nicht bei jedem Patienten angewandt werden. Aufgrund der hohen interindividuellen Variabilität der Pharmakokinetik und Pharmakodynamik sollte bei Alterspatienten während der medikamentösen Behandlung ein enges Monitoring bzgl. Wirksamkeit und Verträglichkeit erfolgen. Blutspiegelmessungen von Psychopharmaka sollten genutzt werden, um pharmakokinetische Besonderheiten und die bei Alterspatienten häufigen Complianceprobleme zu erkennen.
Gewalt- und Tötungsdelikte junger Menschen
Authors: Remschmidt H. , Martin M. , Niebergall G. , Heinzel-Gutenbrunner M.
Published: September 2018

Fragestellung: Berichtet wird über eine Verlaufsuntersuchung an jugendlichen und heranwachsenden Gewalt- und Tötungsdelinquenten (n=114), deren legale Entwicklung über einen Zeitraum von 12,8 Jahren verfolgt werden konnte. Ergebnisse: Unter den psychiatrischen Diagnosen nach ICD-10 (nur in 18 Fällen war keine solche zu stellen) standen in der Delinquentenstichprobe an erster Stelle Persönlichkeits- und Verhaltensstörungen (41,2%), gefolgt von Störungen des Sozialverhaltens (27,2%), Schizophrenien und wahnhaften Störungen (7%) und Störungen durch psychotrope Substanzen (5,3%). 2 Probanden (1,8%) litten an einem hyperkinetischen Syndrom und je einer an einer affektiven bzw. neurotischen Störung. Im Vergleich mit einer parallelisierten Patientenstichprobe wiesen die Straftäter im Marburger Symptom Rating (MSR) signifikant höhere Werte auf in den Symptomen Dissoziales Verhalten, Aggressivität, Drogen- und Alkoholmissbrauch, jedoch signifikant niedrigere Angstwerte. 44 der Probanden (38,5%) entwickelten sich zu chronischen Straftätern, die auch nach der Indextat weitere Delikte verübten. Als Untergruppe der chronischen Straftäter konnten 13 (11,4% der Gesamtstichprobe) als Mehrfachintensivtäter identifiziert werden, die in jeder Hinsicht am auffälligsten waren.
Zerebrale und psychische Folgen sportassoziierter Schädelhirntraumata
Authors: Henkel K. , Schneider F.
Published: September 2018

Auch leichte sportbedingte Schädelhirntraumata (SHT), inklusive Gehirnerschütterungen, können zu kurzfristigen, prolongierten und dauerhaften strukturellen und funktionellen Hirnschädigungen führen. Es besteht eine Evidenz für kumulative Schädigungsrisiken bei repetitiven Traumata. Die resultierenden Störungen betreffen kognitive, psychische und motorische Funktionen. Die strukturellen Alterationen reichen von Konnektivitätsänderungen über Fasertraktläsionen bis hin zu schwerwiegenden neurodegenerativen Prozessen. Mittels moderner Diagnoseverfahren lassen sich auch subklinische Funktionsstörungen nachweisen. Zudem mehren sich die Erkenntnisse, dass auch wiederholte subklinische SHT zu relevanten zerebralen Veränderungen führen können. Ein adäquates initiales Trauma-management kann dazu beitragen, schwerwiegende Folgeerscheinungen zu minimieren.
Bouncing ball on a vibrating periodic surface
Authors: Halev Avishai , Harris Daniel M.
Published: September 2018

We present an investigation of a partially elastic ball bouncing on a vertically vibrated sinusoidal surface. Following the work of McBennett and Harris [Chaos 26, 093105 (2016)], we begin by demonstrating that simple periodic vertical bouncing at a local minimum of the surface becomes unstable when the local curvature exceeds a critical value. The resulting instability gives rise to a period doubling cascade and results in persistent horizontal motion of the ball. Following this transition to horizontal motion, periodic “walking” states—where the ball bounces one wavelength over each vibration cycle—are possible and manifest for a range of parameters. Furthermore, we show that net horizontal motion in a preferred direction can be induced by breaking the left-right symmetry of the periodic topography.
Numerical simulation of thermochemically non-equilibrium inductively coupled plasmas under different operating parameters
Authors: Lu B. X. , Feng Q. K.
Published: September 2018

A thermochemical non-equilibrium model for inductively coupled plasmas (ICPs) has been utilized to investigate the effect of different operating parameters. The effects of operating parameters, including the injection mass flow rate, input power, operating pressure, and induction frequency, are studied in this manuscript. The spatial distributions of electron temperature, plasma velocity, and chemical particles fields are discussed under different operating conditions. The simulation results show that the spatial characteristics of ICP torch have a strong relationship with the variation of operating parameters, especially the pressure. However, the induction frequency over the range investigated is proved to have little significant effect on the distributions of plasma fields. This numerical model is helpful to determine the optimum conditions for the generation of the desired plasma.
Role of electrostatic correlations in polyelectrolyte charge association
Authors: Friedowitz Sean , Salehi Ali , Larson Ronald G. , Qin Jian
Published: September 2018

Reversible ion binding equilibria in polyelectrolyte solutions are strongly affected by interactions between dissociated ionic species. We examine how the structural correlations between ionic groups on polyelectrolytes impact the counterion binding. Treating the electrostatic correlation free energy using the classical Debye-Hückel expression leads to complete counterion dissociation in the concentrated regime. This unphysical behavior is shown to stem from improper regularization of the self-energy of dissociated ions and polyions and is mitigated by smearing point-like charges across a finite width. The influence of the self-energy on counterion binding is elaborated on by generalizing the Debye-Hückel free energy to polyelectrolytes with variable fractal dimension and stiffness. In the dilute regime, a greater propensity for binding is found for chains with more compact architectures, which in turn reduces the harsh self-repulsions of tightly packed arrangements of charge. In the concentrated regime, the effects of electrostatic correlations weaken due to screening and the extent of binding is governed by a balance of short-ranged interactions and the translational entropy of ions.
Strong bonds and far-from-equilibrium conditions minimize errors in lattice-gas growth
Authors: Whitelam Stephen
Published: September 2018

We use computer simulation to study the layer-by-layer growth of particle structures in a lattice gas, taking the number of incorporated vacancies as a measure of the quality of the grown structure. A dynamic scaling relation describes the quality of structures in and out of equilibrium and reveals that the highest-quality structures are obtained, for fixed observation time, using strong interactions and far-from-equilibrium growth conditions. This result contrasts with the usual assumption that weak interactions and mild nonequilibrium conditions are the best way to minimize errors during assembly.
Electron sheath evolution controlled by a magnetic field in modified hollow cathode glow discharge
Authors: Rane R. , Chauhan S. , Bharathi P. , Nigam K. , Bandyopadhyay P. , Mukherjee S.
Published: September 2018

The electron sheath formation in a DC magnetised plasma of modified hollow cathode source is studied. The discharge consists of two plane parallel cathodes and a small cubical anode placed off axis at the center. The argon plasma is produced, and the properties of the plasma in response to the sheath formation near the anode are studied using electrical and optical diagnostics. In particular, the effect of pressure and magnetic field on the discharge parameters, such as discharge current, plasma potential, plasma density, and electron temperature, is studied. The discharge showed an onset of anode glow at a critical applied magnetic field, indicating the formation of electron sheath and a double layer. The discharge current initially decreases; however, it starts to rise again as the anode spot appears on the anode. The critical magnetic field at which the anode glow formation takes place is dependent upon operating pressure and discharge voltage. The transition from ion sheath to electron sheath is investigated in detail by Langmuir probe and spectroscopy diagnostics. The plasma potential near the anode decreases during the transition from ion sheath to electron sheath. The plasma potential locks to the ionization potential of argon gas when anode spot is completely formed. A systematic study showed that during the transition, the electron temperature increases and plasma density decreases in the bulk plasma. The spectroscopy of the discharge showed the presence of strong atomic and ionic lines of argon. The intensity of these spectral lines showed a dip during the transition between two sheaths. After the formation of the anode spot, oscillations of the order of 5–20 kHz are observed in the discharge current and floating potential due to the enhanced ionisation and excitation processes in the electron sheath. The reason for the electron sheath formation at particular magnetic field is attributed to the reduction of the electron flux reaching to the anode in the direction perpendicular to the magnetic field.
Light-induced magnetization changes in aggregated and isolated cobalt ferrite nanoparticles
Authors: Brinzari Tatiana V. , Rajan Divya , Ferreira Cauê F. , Stoian Sebastian A. , Quintero Pedro A. , Meisel Mark W. , Talham Daniel R.
Published: September 2018

The light-induced magnetization changes in cobalt ferrite nanoparticles are reinvestigated to probe the mechanism of photomagnetic behavior and to uncover the essential criteria required to observe the effect. Irradiation with white light results in pronounced demagnetization as evidenced by a decrease in the coercivity (ΔHc ∼ 3 kOe at 10 K) and a drop in the high field magnetization at 70 kOe. Wavelength dependent studies show the optical excitation driving the effect is broad in nature. Power and temperature (T) dependent measurements reveal strikingly different photomagnetic behaviors for the high field magnetization and coercive fields with energy scales of 25 K and 200 K, respectively. Importantly, the magnitude of the light-induced change in the magnetization is found to be specific to the synthesis protocol, with aggregated nanoparticles showing a larger effect than isolated particles. Mössbauer spectroscopy provides additional evidence of the differences between the aggregated and isolated nanoparticle samples. For T ≲ 25 K, the photo-response arises from magnetic disorder generated by an elevated electronic temperature in the surface layer of the particles, thereby leading to a decrease in magnetic volume. For 25 K ≲ T ≲ 200 K, the electronic and phononic reservoirs are more intimately coupled, so the photo-induced magnetic response follows the temperature dependence of the magneto-crystalline anisotropy. A similar response in manganese ferrite suggests that the mechanism is general.
Effects of external forcing on evolutionary games in complex networks
Authors: Huang Keke , Zhang Yichi , Li Yonggang , Yang Chunhua , Wang Zhen
Published: September 2018

How did cooperation evolve in a complex network is an intensely investigated problem. Many mechanisms that promote cooperation have been proposed within the framework of the evolutionary game theory. Motivated by the fact that people in society or even a certain group are often controlled by a variety of simple rules, we present an external forcing mechanism to analyze the underlying reasons of widespread cooperation in this paper. In detail, we model the agents on a simple regular network, on which the learning method is controlled by external forcing mechanism, and prisoner’s dilemma has been applied to describe the interaction of agents. By conducting large-scale Monte Carlo simulations, we can easily draw a conclusion that this mechanism can promote cooperation efficiently. In addition, we also show that the proposed mechanism is effective for the cooperation promotion for other game models, such as snowdrift game and multigames. Taken together, the mechanism of external forcing on the evolutionary game is a strong promoter of cooperation even under a severe temptation condition, which has a practical significance and will provide new insight into the analysis and control of cooperative strategy in the complex network for the further research.
Spin and orbital magnetism in phthalocyanine functionalized with 3d transition metals: A relativistic density functional theory study
Authors: Afshar M. , Darabi A. , Moradi H.
Published: September 2018

The structural, magnetic, and electronic properties of 3d transition metal phthalocyanines, TMPc (TM = Sc-Ni, Cu), were studied by a full potential local orbital method in the framework of relativistic density functional theory. Binding energies, charge transfers, spin and orbital magnetic moments, and magnetic anisotropy energies were determined. Spin-orbit coupling in full relativistic regime together with orbital polarization correction to the exchange-correlation functional added a notable orbital contribution to magnetic moments of the individual 3d transition metals. In the presence of orbital polarization correction, significant in-plane orbital magnetic moments of 1.38 μB and 1.03 μB were found for vanadium atom in VPc and cobalt atom in CoPc, respectively. Besides, VPc showed planar magnetic anisotropy with 51.5 meV energy gain. Our calculations revealed that FePc has an out-of-plane easy axis.
Stress correlations in glasses
Authors: Lemaître Anaël
Published: September 2018

We rigorously establish that, in disordered three-dimensional isotropic solids, the stress autocorrelation function presents anisotropic terms that decay as 1/r3 at long-range, with r being the distance, as soon as local stress fluctuations are normal, by which we mean that the fluctuations of stress, as averaged over spherical domains, decay as the inverse domain volume. Since this property is required for macroscopic stress to be self-averaging, it is expected to hold generically in all glasses and we thus conclude that the presence of 1/r3 stress correlation tails is the rule in these systems. Our proof follows from the observation that, in an infinite medium, when both material isotropy and mechanical balance hold, (i) the stress autocorrelation matrix is completely fixed by just two radial functions: the pressure autocorrelation and the trace of the autocorrelation of stress deviators; furthermore, these two functions (ii) fix the decay of the fluctuations of sphere-averaged pressure and deviatoric stresses with the increasing sphere volume. Our conclusion is reached because, in view of (ii), the normal decay of stress fluctuations is only compatible with both the pressure autocorrelation and the trace of the autocorrelation of stress deviators being integrable; in turn, due to the precise analytic relation (i) fixed by isotropy and mechanical balance, this condition demands the spatially anisotropic stress correlation terms to decay as 1/r3 at long-range.
Integration of cell-free protein synthesis and purification in one microfluidic chip for on-demand production of recombinant protein
Authors: Xiao Xiao , Zhou Yuan , Sun Yuqiong , Wang Qing , Liu Jianbo , Huang Jin , Zhu Xiaobei , Yang Xiaohai , Wang Kemin
Published: September 2018

Recombinant proteins have shown several benefits compared with their non-recombinant counterparts in protein therapeutics. However, there are still some problems with the storage and distribution of recombinant proteins, owing to their temperature sensitivity. Microfluidic chips can integrate different functional modules into a single device because of the advantages of integration and miniaturization, which have the special potential to synthesize drugs when and where they are needed most. Here, we integrated cell-free protein synthesis and purification into a microfluidic chip for the production of recombinant protein. The chip consisted of a main channel and a branch channel. The main channel included two pinches, which were filled with template DNA-modified agarose microbeads and nickel ion-modified agarose beads as the cell-free protein synthesis unit and protein purification unit, respectively. The reaction mixture for protein synthesis was introduced into the main channel and first passed through the protein synthesis unit where the target protein was synthesized; next, the reaction mixture passed through the protein purification unit where the target protein was captured; and, finally, pure protein was collected at the outlet when washing buffer and eluting buffer were sequentially introduced into the branch channel. Enhanced green fluorescent protein (EGFP) was used as the model to investigate the performance of our chip. One chip could produce 70 μl of EGFP solution (144.3 μg/ml, 10.1 μg) per batch, and another round of protein synthesis and purification could be performed after replacing or regenerating nickel ion-modified agarose beads. It should be possible to produce other recombinant proteins on demand with this chip by simply replacing the template DNA.
Galloping-based energy harvester considering enclosure effect
Authors: Jo Soohwan , Sun Wan , Son Choneung , Seok Jongwon
Published: September 2018

A galloping-based energy harvester, which is surrounded by structure(s) such as an enclosure, has an aerodynamic force change due to a change in flow caused by movement of the bluff body against the structure(s). Therefore, any model derived without considering this effect cannot predict the harvester’s behavioral or energetic characteristics accurately. The main goal of this study was to develop a model that could be used to accurately simulate a galloping-based energy harvester surrounded by an enclosure. To consider the effect of the enclosure on the aerodynamic force applied to the bluff body, a bivariate quasi-static aerodynamic force model was newly proposed, which was accomplished by performing an experiment involving two variables, the attack angle, and the distance from the nearest wall of the bluff body. A set of governing nonlinear field equations reflecting this force model were derived, and their perturbed solutions were obtained and validated by comparison with experimental results. The effect of the enclosure on the performance of the present energy harvester system was investigated and discussed using both theoretical and experimental methods.
Bio-inspired self-agitator for convective heat transfer enhancement
Authors: Li Zheng , Xu Xianchen , Li Kuojiang , Chen Yangyang , Ke Zhaoqing , Wang Sheng , Chen Hsiu-Hung , Huang Guoliang , Chen Chung-Lung , Chen Chien-Hua
Published: September 2018

Convective heat transfer plays an important role in both the fundamental research and the development of high-performance heat exchangers. Inspired by blades of grass vibrating in the wind, we developed a self-agitator for convective heat transfer enhancement. Because of fluid-structure interactions, the agitator, with self-sustained vibration, can generate strong vortices to significantly break the thermal boundary layer and improve fluid mixing for enhanced convective heat transfer. In particular, we establish a methodology to link the vorticity field at a preferred frequency to the optimal improvement in the convective heat transfer. To identify the self-agitator preferred frequency, mode analysis is performed with simulation results using dynamic mode decomposition. Experimental results are also obtained to further validate the proposed approach. These results show that the proposed self-agitator design can improve the convective heat transfer by 120% in a conventional heat exchanger without additional pumping power requirements and can achieve a Nusselt number of up to 30 within the laminar flow region, which is improved by 200% with the same Reynolds number compared to the clean channel.
The dielectric strength of dissociated cryogenic gas media
Authors: Park Chanyeop , Pamidi Sastry , Graber Lukas
Published: September 2018

The dielectric strength of dissociated binary and ternary gas mixtures containing helium, hydrogen, and nitrogen for cryogenic power applications is reported. The compositions of the dissociated gas species in the temperature range of 77–5000 K at 1.0–2.0 MPa are obtained by minimizing the Gibbs free energy assuming local chemical equilibrium. The resulting mole fractions of the dissociated gas species that vary as a function of temperature and pressure are used for calculating the density-reduced critical electric field representing the dielectric strength. The results suggest that the He-H2-N2 mixture has higher dielectric strength than the He-H2 and He-N2 mixtures, but NH3 would potentially accumulate over multiple arcing and cooling cycles and potentially cause long-term issues in cryogenic switchgear applications. On the other hand, the binary alternatives, the He-H2 and He-N2 mixtures, show lower dielectric strength than the ternary gas mixture but will maintain their original gas properties even over multiple arcing and cooling cycles. The results also show that the dielectric strength of the He-H2-N2 and He-H2 mixtures decreases substantially with increasing temperature whereas that of the He-N2 mixture stays nearly unchanged. The results of this study are useful for the fundamental understanding of gas dielectrics under arcing conditions in cryogenic switchgear applications and the development of resilient cryogenic power systems.
Tree rings and growth trajectories of tree species from seasonally dry tropical forest
Authors: Barbosa Ana Carolina Maioli , Pereira Gabriel Assis , Granato-Souza Daniela , Santos Rubens Manoel , Fontes Marcos Aurélio Leite
Published: September 2018

The presence of distinct growth rings in a large number of tropical tree species has allowed a range of studies involving the growth history during the life span of the tree. This work aimed to examine the presence of tree rings and study growth patterns of tree species from five seasonally dry tropical forest fragments. Wood cores were extracted using 5-mm increment borer. The macroscopic structure of growth rings from 24 deciduous tree species was observed under stereomicroscope and classified according to anatomical features and visibility of the ring boundary. Distinct growth rings were detected for 19 species (79%). Seven species were submitted to tree-ring analyses, including cross-dating and dating quality control using the COFECHA program. Dated ring-series were analysed by comparing increment rates and accumulated diameter at breast height fitted curves to detect growth patterns. The variations among growth curves indicated different strategies of establishment and development for each studied species, and allowed the identification of different ecological groups. The results show the potential of tree rings to study populations and communities of seasonally dry tropical forest.
Multiple climate impacts on seagrass dynamics: Amphibolis antarctica patches at Ningaloo Reef, Western Australia
Authors: van Keulen Mike
Published: September 2018

The impacts of tropical cyclones combined with a marine heatwave are reported for a seagrass community at Ningaloo Reef, Western Australia. A community of 9.5ha of Amphibolis antarctica was lost following a combination of cyclone-induced burial and a marine heatwave. No new seedlings have been observed since the loss; recruitment of seedlings may be impeded by local ocean circulation.
Neural-inspired sensors enable sparse, efficient classification of spatiotemporal data
Authors: Mohren Thomas L. , Daniel Thomas L. , Brunton Steven L. , Brunton Bingni W.
Published: September 2018

Sparse sensor placement is a central challenge in the efficient characterization of complex systems when the cost of acquiring and processing data is high. Leading sparse sensing methods typically exploit either spatial or temporal correlations, but rarely both. This work introduces a sparse sensor optimization that is designed to leverage the rich spatiotemporal coherence exhibited by many systems. Our approach is inspired by the remarkable performance of flying insects, which use a few embedded strain-sensitive neurons to achieve rapid and robust flight control despite large gust disturbances. Specifically, we identify neural-inspired sensors at a few key locations on a flapping wing that are able to detect body rotation. This task is particularly challenging as the rotational twisting mode is three orders of magnitude smaller than the flapping modes. We show that nonlinear filtering in time, built to mimic strain-sensitive neurons, is essential to detect rotation, whereas instantaneous measurements fail. Optimized sparse sensor placement results in efficient classification with approximately 10 sensors, achieving the same accuracy and noise robustness as full measurements consisting of hundreds of sensors. Sparse sensing with neural-inspired encoding establishes an alternative paradigm in hyperefficient, embodied sensing of spatiotemporal data and sheds light on principles of biological sensing for agile flight control.
Utilizing TAPBPR to promote exogenous peptide loading onto cell surface MHC I molecules
Authors: Ilca F. Tudor , Neerincx Andreas , Wills Mark R. , de la Roche Maike , Boyle Louise H.
Published: September 2018

Significance

MHC class I molecules present small fragments of proteins from within the cell to alert the immune system to infection and cellular damage. Two protein accessory proteins, tapasin and TAPBPR, assist in the loading and selection of these peptides inside the cell. Here we show that one of these proteins, TAPBPR, surprisingly still works when delivered to the outside of cells and can be used to load peptides from viruses and tumours directly on surface MHC molecules. Therefore, we have found an efficient way to override the peptides naturally presented by cells and can use this to target immune responses against cells. This may prove beneficial to mount immune responses against cancer in the future.
Ecological Interdependence via Constraints
Authors: Eliot Christopher H.
Published: September 2018

Although ecological theory has historically focused on negative interactions among populations, like competition and predation, ecologists and conservation biologists highlight the significance of interdependence. It is not clear, however, what is asserted in the causal hypothesis that one population is interdependent on others. This essay argues that the most informative causal regularities for representing dependencies are those connecting populations through environmental constraint variables. Interdependence among populations can thus be understood as constraint-mediated dependency relations connected in a circuit.