bluuebunny/crossref_metadata_2025 huggingface dataset:
Predictor‐based output feedback control design for sampled systems with input delay subject to disturbance
Authors: Hao Shoulin , Liu Tao , Zhou Bin
Published: September 2017

In this study, a predictor‐based output feedback control design is proposed for sampled systems with input delay subject to disturbance. An extended state observer (ESO) is first constructed to simultaneously estimate the system state and disturbance based on only the output measurement. Then a filtered predictor is constructed by using the estimated state and disturbance to compensate the input delay so as to improve the disturbance rejection performance. For the presence of a constant or asymptotically stable disturbance, a robust H infinity feedback control design based on state prediction and disturbance estimation is proposed to realise no steady‐state output error, despite mismatched disturbance. When there exists a time‐varying disturbance with deterministic dynamics, such as a sinusoidal type, the proposed predictor can achieve a small prediction error by properly tuning the filter, such that the existing observer‐based feedback control methods for delay‐free systems can be directly adopted to stabilise such a system with input delay. Moreover, the output error bounds in the presence of time‐varying disturbance are quantitatively analysed for using the ESO‐based predictor feedback and anti‐disturbance predictor feedback, respectively. Two illustrative examples are given to demonstrate the effectiveness and merit of the proposed method.
Linear representation of symmetric games
Authors: Cheng Daizhan , Liu Ting
Published: September 2017

Using the linear representation of symmetric group in the structure vector of finite games as its representation space, the inside structures of several kinds of symmetric games are investigated. First of all, the symmetry, described as the action of symmetric group on payoff functions, is converted to the product of permutation matrices with structure vectors of payoff functions. Second, in the light of the linear representation of the symmetric group in structure vectors, the algebraic conditions for the ordinary, weighted, renaming and name‐irrelevant symmetries are obtained as the invariance under the corresponding linear representations. The semi‐tensor product of matrices is a fundamental tool in this approach.
Recent advances on state estimation for power grids with unconventional measurements
Authors: Hu Liang , Wang Zidong , Liu Xiaohui , Vasilakos Athanasios V. , Alsaadi Fuad E.
Published: September 2017

State estimation problem for power systems has long been a fundamental issue that demands a variety of methodologies depending on the system settings. With the recent introduction of advanced devices of phasor measurement units (PMUs) and dedicated communication networks, the infrastructure of power grids has been greatly improved. Coupled with the infrastructure improvements are three emerging issues for the state estimation problems, namely, the coexistence of both traditional and PMU measurements, the incomplete information resulting from delayed, asynchronous and missing measurements due to communication constraints, and the cyber‐attacks on the communication channels. In this study, the authors aim to survey some recent advances on the state estimation methods which tackle the above three issues in power grids. Traditional state estimation methods applied in power grids are first introduced. Latest results on state estimation with mixed measurements and incomplete measurements are then discussed in great detail. In addition, the techniques developed to ensure the cyber‐security of the state estimation schemes for power grids are highlighted. Finally, some concluding remarks are given and some possible future research directions are pointed out.
“TNOs are Cool”: A survey of the trans-Neptunian region
Authors: Kovalenko I. D. , Doressoundiram A. , Lellouch E. , Vilenius E. , Müller T. , Stansberry J.
Published: September 2017

Context. Gravitationally bound multiple systems provide an opportunity to estimate the mean bulk density of the objects, whereas this characteristic is not available for single objects. Being a primitive population of the outer solar system, binary and multiple trans-Neptunian objects (TNOs) provide unique information about bulk density and internal structure, improving our understanding of their formation and evolution.

Aims. The goal of this work is to analyse parameters of multiple trans-Neptunian systems, observed with Herschel and Spitzer space telescopes. Particularly, statistical analysis is done for radiometric size and geometric albedo, obtained from photometric observations, and for estimated bulk density.

Methods. We use Monte Carlo simulation to estimate the real size distribution of TNOs. For this purpose, we expand the dataset of diameters by adopting the Minor Planet Center database list with available values of the absolute magnitude therein, and the albedo distribution derived from Herschel radiometric measurements. We use the 2-sample Anderson–Darling non-parametric statistical method for testing whether two samples of diameters, for binary and single TNOs, come from the same distribution. Additionally, we use the Spearman’s coefficient as a measure of rank correlations between parameters. Uncertainties of estimated parameters together with lack of data are taken into account. Conclusions about correlations between parameters are based on statistical hypothesis testing.

Results. We have found that the difference in size distributions of multiple and single TNOs is biased by small objects. The test on correlations between parameters shows that the effective diameter of binary TNOs strongly correlates with heliocentric orbital inclination and with magnitude difference between components of binary system. The correlation between diameter and magnitude difference implies that small and large binaries are formed by different mechanisms. Furthermore, the statistical test indicates, although not significant with the sample size, that a moderately strong correlation exists between diameter and bulk density.
Photometric survey, modelling, and scaling of long-period and low-amplitude asteroids
Authors: Marciniak A. , Bartczak P. , Müller T. , Sanabria J. J. , Alí-Lagoa V. , Antonini P. , Behrend R. , Bernasconi L. , Bronikowska M. , Butkiewicz-Bąk M. , Cikota A. , Crippa R. , Ditteon R. , Dudziński G. , Duffard R. , Dziadura K. , Fauvaud S. , Geier S. , Hirsch R. , Horbowicz J. , Hren M. , Jerosimic L. , Kamiński K. , Kankiewicz P. , Konstanciak I. , Korlevic P. , Kosturkiewicz E. , Kudak V. , Manzini F. , Morales N. , Murawiecka M. , Ogłoza W. , Oszkiewicz D. , Pilcher F. , Polakis T. , Poncy R. , Santana-Ros T. , Siwak M. , Skiff B. , Sobkowiak K. , Stoss R. , Żejmo M. , Żukowski K.
Published: September 2017

Context. The available set of spin and shape modelled asteroids is strongly biased against slowly rotating targets and those with low lightcurve amplitudes. This is due to the observing selection effects. As a consequence, the current picture of asteroid spin axis distribution, rotation rates, radiometric properties, or aspects related to the object’s internal structure might be affected too.

Aims. To counteract these selection effects, we are running a photometric campaign of a large sample of main belt asteroids omitted in most previous studies. Using least chi-squared fitting we determined synodic rotation periods and verified previous determinations. When a dataset for a given target was sufficiently large and varied, we performed spin and shape modelling with two different methods to compare their performance.

Methods. We used the convex inversion method and the non-convex SAGE algorithm, applied on the same datasets of dense lightcurves. Both methods search for the lowest deviations between observed and modelled lightcurves, though using different approaches. Unlike convex inversion, the SAGE method allows for the existence of valleys and indentations on the shapes based only on lightcurves.

Results. We obtain detailed spin and shape models for the first five targets of our sample: (159) Aemilia, (227) Philosophia, (329) Svea, (478) Tergeste, and (487) Venetia. When compared to stellar occultation chords, our models obtained an absolute size scale and major topographic features of the shape models were also confirmed. When applied to thermophysical modelling (TPM), they provided a very good fit to the infrared data and allowed their size, albedo, and thermal inertia to be determined.

Conclusions. Convex and non-convex shape models provide comparable fits to lightcurves. However, some non-convex models fit notably better to stellar occultation chords and to infrared data in sophisticated thermophysical modelling (TPM). In some cases TPM showed strong preference for one of the spin and shape solutions. Also, we confirmed that slowly rotating asteroids tend to have higher-than-average values of thermal inertia, which might be caused by properties of the surface layers underlying the skin depth.
IRC +10 216 in 3D: morphology of a TP-AGB star envelope
Authors: Guélin M. , Patel N. A. , Bremer M. , Cernicharo J. , Castro-Carrizo A. , Pety J. , Fonfría J. P. , Agúndez M. , Santander-García M. , Quintana-Lacaci G. , Velilla Prieto L. , Blundell R. , Thaddeus P.
Published: September 2017

During their late pulsating phase, AGB stars expel most of their mass in the form of massive dusty envelopes, an event that largely controls the composition of interstellar matter. The envelopes, however, are distant and opaque to visible and NIR radiation: their structure remains poorly known and the mass-loss process poorly understood. Millimeter-wave interferometry, which combines the advantages of longer wavelength, high angular resolution and very high spectral resolution is the optimal investigative tool for this purpose. Mm waves pass through dust with almost no attenuation. Their spectrum is rich in molecular lines and hosts the fundamental lines of the ubiquitous CO molecule, allowing a tomographic reconstruction of the envelope structure. The circumstellar envelope IRC +10 216 and its central star, the C-rich TP-AGB star closest to the Sun, are the best objects for such an investigation. Two years ago, we reported the first detailed study of the CO(2–1) line emission in that envelope, made with the IRAM 30-m telescope. It revealed a series of dense gas shells, expanding at a uniform radial velocity. The limited resolution of the telescope (HPBW 11″) did not allow us to resolve the shell structure. We now report much higher angular resolution observations of CO(2–1), CO(1–0), CN(2–1) and C4H(24–23) made with the SMA, PdB and ALMA interferometers (with synthesized half-power beamwidths of 3″, 1″ and 0.3″, respectively). Although the envelope appears much more intricate at high resolution than with an 11″ beam, its prevailing structure remains a pattern of thin, nearly concentric shells. The average separation between the brightest CO shells is 16″ in the outer envelope, where it appears remarkably constant. Closer to the star (<40″), the shell pattern is denser and less regular, showing intermediary arcs. Outside the small (r< 0.3′′) dust formation zone, the gas appears to expand radially at a constant velocity, 14.5 km s-1, with small turbulent motions. Based on that property, we have reconstructed the 3D structure of the outer envelope and have derived the gas temperature and density radial profiles in the inner (r< 25′′) envelope. The shell-intershell density contrast is found to be typically 3. The over-dense shells have spherical or slightly oblate shapes and typically extend over a few steradians, implying isotropic mass loss. The regular spacing of shells in the outer envelope supports the model of a binary star system with a period of 700 yr and a near face-on elliptical orbit. The companion fly-by triggers enhanced episodes of mass loss near periastron. The densification of the shell pattern observed in the central part of the envelope suggests a more complex scenario for the last few thousand years.
Challenges in Multivalvular Heart Disease: Indian Scenario
Authors: Ladha Suruchi , Kapoor Poonam
Published: September 2017

Multivalvular disease (MVD) is a common scenario with various clinical challenges and limited availability of evidence-based recommendations. The pathophysiology of patients having MVD is dependent on the specific combination of valve lesions. The anesthesiologist should be aware of the echocardiographic pitfalls as many commonly used echocardiographic parameters for the assessment and quantification of valve lesions is validated only in patients with single-valve disease. It is also necessary to take into account the interaction between the different valve lesions while interpreting echocardiography. The management decisions of such patients depend on the assessment of the different valve lesions and their effect on symptoms, pulmonary hypertension, and left ventricular dysfunction. The decision to intervene on multiple valves should take into account both the surgical risk of combined procedures and the advantages of available percutaneous techniques. In this review, we discuss the common clinical scenario, pathophysiology, echocardiographic challenges, and guideline-directed management options in patients with MVD.
High Altitude and Anesthesia
Authors: Wani Zara , Sharma Meenaxi
Published: September 2017

Anesthesia in any abnormal environment, such as high altitude, is a challenge for all anesthesiologists. To have safe anesthesia at that time, the pathophysiological changes in both the unacclimatized and acclimatized patients at high altitude, which include pulmonary hyperventilation, polycythemia, rising pulmonary blood volume, pulmonary hypertension, and increase in diffusion capacity, are to be considered in preanesthetic checkup.
Extracorporeal Membrane Oxygenation in Cardiac Intensive Care Unit
Authors: Goyal Venkat , Oza Pranay
Published: September 2017

In critical care units, doctors usually witness patients coming with single organ failure and subsequently suffer multiorgan failure before they succumb to the destiny. It is well-known that hardly a few patients die of single organ failure, and with addition of every organ, the risk of mortality increases by 10%. The multiorgan failure is secondary to inadequate organ function, tissue perfusion, and oxygenation or due to iatrogenic causes. Extracorporeal membrane oxygenation (ECMO) is not a treatment by itself but a mechanical assist device or rather a replacement therapy to sustain life, to give rest to the organs, and to maintain adequate perfusion and oxygenation. There are various articles discussing the outcomes of ECMO in cardiogenic shock with varied etiology. ECMO support can rescue 40% of patients with otherwise fatal cardiogenic shock (mortality without ECMO is > 80%). As per ELSO data January 2017, 10,982 patients were reported in adult cardiac ECMO, out of whom 56% survived ECLS and 40% survived to discharge. The newer scoring system named SAVE score (its online calculator [www.save-score.com]) offers a validated tool to predict survival for patients receiving ECMO for refractory cardiogenic shock.
Facial Volume Restoration with Permanent Dermal Filler (Artecoll-4) in Chinese Women
Authors: Li Dong , Luo Sheng-Kang , Wang Yi-Chao , Lemperle Gottfried
Published: September 2017

Artecoll is the only permanent dermal filler to be approved by the European Union and China Food and Drug Administration, and has been used worldwide since 1994 in approximately 400,000 patients. Since 2002, Artecoll-4 has also been injected in China in more than 42,000 patients in more than 100 hospitals, primarily for beauty refinement in younger patients and for rejuvenation of the aging face. Artecoll-4 consists of polymethylmethacrylate (PMMA) microspheres (20% by volume) 40 µm in diameter, suspended in 3.5% bovine collagen solution and 0.3% lidocaine. The collagen carrier is absorbed rather early after injection and is completely replaced by the patient's own connective tissue within the first 3 months. Thus, in contrast to all other fillers, Artecoll-4 becomes the patient's own tissue, and it is a “living implant.” In this study, a total of 10,725 patients were treated in 25 Chinese cosmetic hospitals between 2007 and 2012. Optimal injection techniques, efficiency and lasting duration, complications, safety, outcome, and statistical results are discussed. The data support the safety and efficiency of large volumes of Artecoll-4 (5–10 mL) injected deep into the faces of Chinese women, who seek to have a smooth oval face without indentations. No foreign body granulomas have been reported since the recommendation for strict epiperiosteal injections. Level of evidence is Level IV, multiple center study.
Dermal Histology in Mouse Skin Exposed to Cosmeceuticals
Authors: Bueller Hope , Hsia Yvonne , Thomas J. , Bhattacharyya Tapan
Published: September 2017

Chronic exposure to environmental ultraviolet radiation elicits deleterious photoaging changes and histopathological damage to the skin. In addition to cosmetic surgical procedures, over-the-counter products described as cosmeceuticals are widely used by a large segment of globally aging populations to partially reverse changes induced by photoaging. Many such products are rarely examined in the laboratory to examine their ameliorative properties and microscopic effects on various skin compartments. The hairless mouse is a popular animal model widely used over the last few decades by researchers to compare cosmeceuticals about their properties to combat or reverse cutaneous photoaging changes. In the present experiment, five cosmeceuticals were topically administered to the dorsal skin over 2 weeks in the nonirradiated mice, and skin samples were analyzed for dermal histopathological changes. Histomorphometric procedures were employed to generate quantitative data on skin sections prepared with immunohistochemistry and staining technics, and the data statistically examined. Among the five agents tested, glycolic acid and retinoic acid produced striking changes, while vitamin C, estrogen, and soy product resulted in less remarkable responses. These quantitative data will be useful for further photoaging studies with these cosmeceuticals.
Oblique Turnover Flap for Repositioning and Flattening of the Lateral Crura: A Novel Technique to Manage Cephalic Malposition of Lower Lateral Cartilage
Authors: Vladykina Elena , Goksel Abdulkadir
Published: September 2017

Malposition of the lower lateral cartilage (LLC) is a relatively common anatomical variation, described as any displacement of the lateral crura from the usual parallel direction with the nostril rims. Cephalic malpositioned LLC has the following characteristics: abnormal axes of the lateral crura, bulbous and broad nasal tip, parenthesis deformity, long alar creases, alar wall hollows, nostril deformities, and incompetence of the external valve. Numerous techniques were founded to correct this aesthetic and functional unpleasant variation, although all of them have some limitations. The authors described and evaluated the efficacy of the oblique turnover flap (OTOF) technique in the management of cephalic malposition of LLC (CMLLC). The advantages of this technique are: it does not need any additional grafting; it is quick and safe to perform; it has stable results. In the present study, 24 primary rhinoplasties using OTOF technique were performed between January 2014 and September 2016. There were 21 females (87.5%) and 3 males (12.5%), with age ranging from 23 to 46 years. The mean follow-up period was 12.1 months (range: 8–28 months). All patients were treated by the senior author (A.G.) in the RinoIstanbul Clinic. Three parameters were measured and compared pre- and postoperatively, using a t-test and a p value criteria of 0.05. The difference was found to be statistically significant: the angle between the central axis of the lateral crura and the septum on each side, satisfaction scale rating of the patients' nasal tip appearance and the satisfaction scale rating of patients' nose breathing. The angle of the central axis of lateral cruras to the midline significantly increased, the mean satisfactory scale ratings of nasal tip appearance and breathing quality were also significantly improved. OTOF is a quick, useful, efficient technique for repositioning and flattening of the lateral cruras of CMLLC with a good, predictable, and stable long-term results in our hands if used on right candidates.
The First Reported Case of Second Impact Syndrome: A Reexamination of Dr Fekete's Case Report from 1968
Authors: Gordon K.
Published: September 2017

Background In the December 28, 1968 edition of the Canadian Medical Association Journal, Dr John Fekete described a 16-year-old hockey player with fatal cerebral edema following a brain impact while actively symptomatic of a concussion incurred 4 days ago. This case has been described as a “possible” case of second impact syndrome, an entity that was named in 1984 and purportedly first described by Schneider in 1973.

Method An audit of material in the public register of Dr Fekete's case was undertaken. Information sources included the newspaper report of the death, transcripts from a coroner's inquest held 12 days later, including the autopsy report, genealogical data available online, and available internet resources.

Results There was clear documentation of concussive symptomatology following an initial head injury and evidence of a medical assessment, thus fulfilling the “definite” clinical criteria for second impact syndrome as proposed. After 4 days of ongoing concussive symptomatology, a dramatic, rapid neurological deterioration took place following an apparently unremarkable body contact and fall on the ice while playing hockey. His primary brain pathology included cerebral edema.

Conclusion Cerebral edema may follow primary or secondary head injury, the latter comprising second impact syndrome. Dr Fekete's case, as described in the December 28, 1968 edition of the Canadian Medical Association Journal, should be recognized as the first description of this condition.
Körperbezogenes Vermeidungsverhalten: Validierung des deutschsprachigen Body Image Avoidance Questionnaire (BIAQ) an Jugendlichen mit Anorexia und Bulimia Nervosa sowie einer gesunden Kontrollgruppe
Authors: Steinfeld Beate , Waldorf Manuel , Bauer Anika , Huber Thomas , Braks Karsten , Vocks Silja
Published: September 2017

Körperbezogenes Vermeidungsverhalten wird als behaviorale Manifestation einer Körperbildstörung konzeptualisiert und beschreibt Anstrengungen, der Auseinandersetzung mit dem eigenen Körper aus dem Wege zu gehen. Während Studien Hinweise darauf liefern, dass körperbezogenes Vermeidungsverhalten im Erwachsenenalter zur Entstehung und Aufrechterhaltung von Essstörungen beiträgt, existieren bisher keine entsprechenden Befunde für das Jugendalter. Der Body Image Avoidance Questionnaire (BIAQ) ist der international am weitesten verbreitete Fragebogen zur Messung des körperbezogenen Vermeidungsverhaltens. Da seine deutschsprachige Version bisher nur an einer Stichprobe aus Erwachsenen validiert wurde, ist das Ziel der vorliegenden Studie, den Fragebogen an Jugendlichen mit Essstörungen teststatistisch zu überprüfen. Insgesamt N=127 weibliche Jugendliche, davon n=57 mit einer Anorexia Nervosa und n=24 mit einer Bulimia Nervosa (BN) sowie n=46 gesunde weibliche Jugendliche beantworteten den BIAQ und verschiedene Instrumente zur Erfassung der Körperbild- und Essstörungssymptomatik. Die für die englischsprachige Originalversion angenommene Faktorenstruktur von dem Faktor höherer Ordnung „Körperbezogenes Vermeidungsverhalten“ und den 4 Subfaktoren „Kleidung“, „Soziale Aktivitäten“, „Gezügeltes Essverhalten“ sowie „Pflegen und Wiegen“ konnte durch eine konfirmatorische Faktorenanalyse bestätigt werden. Mit Ausnahme der Skala „Pflegen und Wiegen“ weisen alle Skalen eine überwiegend akzeptable interne Konsistenz, Test-Retest-Reliabilität, differenzielle Validität sowie Konstruktvalidität auf. Aufgrund ihrer befriedigenden psychometrischen Kennwerte ist der Einsatz der BIAQ-Skalen „Kleidung“, „Soziale Aktivitäten“ und „Gezügeltes Essverhalten“ auch für das Jugendalter in Forschung und Praxis zu empfehlen.
Underwater endoscopic mucosal resection for superficial nonampullary duodenal adenomas
Authors: Yamasaki Yasushi , Uedo Noriya , Takeuchi Yoji , Higashino Koji , Hanaoka Noboru , Akasaka Tomofumi , Kato Minoru , Hamada Kenta , Tonai Yusuke , Matsuura Noriko , Kanesaka Takashi , Arao Masamichi , Suzuki Sho , Iwatsubo Taro , Shichijo Satoki , Nakahira Hiroko , Ishihara Ryu , Iishi Hiroyasu
Published: September 2017

Background and study aim Underwater endoscopic mucosal resection (UEMR) was recently developed in a Western country. A prospective cohort study to investigate the effectiveness of UEMR was conducted in patients with small superficial nonampullary duodenal adenomas.

Patients and methods Patients with duodenal adenomas ≤ 20 mm were enrolled. After the duodenal lumen had been filled with physiological saline, UEMR was performed without submucosal injection. Endoclip closure was attempted for all mucosal defects after UEMR. Follow-up endoscopy with biopsy was performed 3 months later. The primary end point was the complete resection rate, defined as neither endoscopic nor histological residue of adenoma at the follow-up endoscopy.

Results 30 patients with 31 lesions were enrolled. The mean (SD) tumor size was 12.0 mm (7.3). The complete resection rate was 97 % (90 % confidence interval, 87 % – 99 %). The en bloc resection rate was 87 %. All mucosal defects were successfully closed by endoclips. No adverse events occurred except for one case of mild aspiration pneumonia.

Conclusions UEMR is efficacious for the treatment of small duodenal adenomas, but further large-scale trials are warranted to confirm these results.

Trial registered at University Hospital Medical Network Clinical Trials Registry (UMIN 000018710).
The disappearance of causality at small scale in almost-commutative manifolds
Authors: Bizi Nadir , Besnard Fabien
Published: September 2017

This paper continues the investigations of noncommutative ordered spaces put forward by one of the authors. These metaphoric spaces are defined dually by the so-called isocones which generalize to the noncommutative setting the convex cones of order-preserving functions. In this paper we will consider the case of isocones inside almost-commutative algebras of the form C(M)⊗Af, with M a compact metrizable space. We will give a family of isocones in such an algebra with the property that every possible isocone is contained in exactly one member of the family. We conjecture that this family is in fact a complete classification, a hypothesis related with the noncommutative Stone-Weierstrass conjecture. We also obtain that every isocone in C(M)⊗Af, with Af noncommutative, induces an order relation on M with the property that every point in M lies in a neighbourhood of incomparable points. Thus, if the causal order relation on spacetime is induced by an isocone in an almost-commutative (but not commutative) algebra, then causality must disappear at small scale. The usual Lorentzian causality would then only arise as an approximation of this noncommutative causality.
Gyromagnetic autoresonance plasma bunches in a magnetic mirror
Authors: Andreev V. V. , Chuprov D. V. , Ilgisonis V. I. , Novitsky A. A. , Umnov A. M.
Published: September 2017

Experiments with relativistic plasmas obtained and confined in a magnetic mirror under gyromagnetic autoresonance and their computer simulations are described. Plasma bunches with relativistic electrons are generated. The averaged energy of the electrons in the bunch is about few hundreds keV depending on the parameters of seed plasma, microwave electric field strength, and the rate of the pulse magnetic field increase. Varying the values of these parameters, it is possible to control the bunches.
Theory and discretization of ideal magnetohydrodynamic equilibria with fractal pressure profiles
Authors: Kraus B. F. , Hudson S. R.
Published: September 2017

In three-dimensional ideal magnetohydrodynamics, closed flux surfaces cannot maintain both rational rotational-transform and pressure gradients, as these features together produce unphysical, infinite currents. A proposed set of equilibria nullifies these currents by flattening the pressure on sufficiently wide intervals around each rational surface. Such rational surfaces exist at every scale, which characterizes the pressure profile as self-similar and thus fractal. The pressure profile is approximated numerically by considering a finite number of rational regions and analyzed mathematically by classifying the irrational numbers that support gradients into subsets. Applying these results to a given rotational-transform profile in cylindrical geometry, we find magnetic field and current density profiles compatible with the fractal pressure.
Magnetic response of a viscoelastic ferrodispersion: From a nearly Newtonian ferrofluid to a Jeffreys ferrogel
Authors: Rusakov V. V. , Raikher Yu. L.
Published: September 2017

The theory of orientational motion of a Brownian magnetic nanoparticle embedded in a viscoelastic medium and subjected to a time-dependent uniform magnetic field is developed. The rheology of the viscoelastic environment of the particle is modeled by the Jeffreys scheme, which under variation of a minimal number of parameters is able to resemble a wide range of soft materials: from a weakly structured (nearly Newtonian) polymer solution to a gel. It is shown that in the Jeffreys model, the diffusional orientational motion of a particle is a combination of two modes, which could be associated with a fast motion within the polymer mesh cell and a slow displacement that involves deformation of the mesh, respectively. The dependencies of the reference times of both relaxation modes on the Jeffreys viscous and elastic parameters and temperature are found. It turns out that in substantially viscoelastic media, the rate of the slow mode (it dominates in relaxation) quadratically depends on the matrix temperature. This effect does not have analogs in linearly viscous systems. For an ensemble of magnetic nanoparticles in viscoelastic and gel Jeffreys matrices: (1) the dynamic magnetic susceptibility is derived and evaluated both within an exact approach and in a simple approximation; (2) the problem of magnetic relaxometry, i.e., evolution of magnetization after step-wise turning off the field, is solved; (3) the specific power loss caused by viscous dissipation generated by the particles under an ac field is analyzed as a function of the rheological parameters. Results (1) and (2) provide simple models for magnetic nanorheology; consideration (3) advances the physics of magnetic hyperthermia in viscoelastic and gel-like media.
Laser ablated hydantoin: A high resolution rotational study
Authors: Alonso Elena R. , Kolesniková Lucie , Alonso José L.
Published: September 2017

Laser ablation techniques coupled with broadband and narrowband Fourier transform microwave spectroscopies have allowed the high resolution rotational study of solid hydantoin, an important target in astrochemistry as a possible precursor of glycine. The complicated hyperfine structure arising from the presence of two 14N nuclei in non-equivalent positions has been resolved and interpreted in terms of the nuclear quadrupole coupling interactions. The results reported in this work provide a solid base for the interstellar searches of hydantoin in the astrophysical surveys. The values of the nuclear quadrupole coupling constants have been also discussed in terms of the electronic environment around the respective nitrogen atom.
Ferroelectricity and piezoelectricity in soft biological tissue: Porcine aortic walls revisited
Authors: Lenz Thomas , Hummel Regina , Katsouras Ilias , Groen Wilhelm A. , Nijemeisland Marlies , Ruemmler Robert , Schäfer Michael K. E. , de Leeuw Dago M.
Published: September 2017

Recently reported piezoresponse force microscopy (PFM) measurements have proposed that porcine aortic walls are ferroelectric. This finding may have great implications for understanding biophysical properties of cardiovascular diseases such as arteriosclerosis. However, the complex anatomical structure of the aortic wall with different extracellular matrices appears unlikely to be ferroelectric. The reason is that a prerequisite for ferroelectricity, which is the spontaneous switching of the polarization, is a polar crystal structure of the material. Although the PFM measurements were performed locally, the phase-voltage hysteresis loops could be reproduced at different positions on the tissue, suggesting that the whole aorta is ferroelectric. To corroborate this hypothesis, we analyzed entire pieces of porcine aorta globally, both with electrical and electromechanical measurements. We show that there is no hysteresis in the electric displacement as well as in the longitudinal strain as a function of applied electric field and that the strain depends on the electric field squared. By using the experimentally determined quasi-static permittivity and Young's modulus of the fixated aorta, we show that the strain can quantitatively be explained by Maxwell stress and electrostriction, meaning that the aortic wall is neither piezoelectric nor ferroelectric, but behaves as a regular dielectric material.
Hamilton-Jacobi theory in multisymplectic classical field theories
Authors: de León Manuel , Prieto-Martínez Pedro Daniel , Román-Roy Narciso , Vilariño Silvia
Published: September 2017

The geometric framework for the Hamilton-Jacobi theory developed in the studies of Cariñena et al. [Int. J. Geom. Methods Mod. Phys. 3(7), 1417–1458 (2006)], Cariñena et al. [Int. J. Geom. Methods Mod. Phys. 13(2), 1650017 (2015)], and de León et al. [Variations, Geometry and Physics (Nova Science Publishers, New York, 2009)] is extended for multisymplectic first-order classical field theories. The Hamilton-Jacobi problem is stated for the Lagrangian and the Hamiltonian formalisms of these theories as a particular case of a more general problem, and the classical Hamilton-Jacobi equation for field theories is recovered from this geometrical setting. Particular and complete solutions to these problems are defined and characterized in several equivalent ways in both formalisms, and the equivalence between them is proved. The use of distributions in jet bundles that represent the solutions to the field equations is the fundamental tool in this formulation. Some examples are analyzed and, in particular, the Hamilton-Jacobi equation for non-autonomous mechanical systems is obtained as a special case of our results.
Effect of bond-disorder on the phase-separation kinetics of binary mixtures: A Monte Carlo simulation study
Authors: Singh Awaneesh , Singh Amrita , Chakraborti Anirban
Published: September 2017

We present Monte Carlo (MC) simulation studies of phase separation in binary (AB) mixtures with bond-disorder that is introduced in two different ways: (i) at randomly selected lattice sites and (ii) at regularly selected sites. The Ising model with spin exchange (Kawasaki) dynamics represents the segregation kinetics in conserved binary mixtures. We find that the dynamical scaling changes significantly by varying the number of disordered sites in the case where bond-disorder is introduced at the randomly selected sites. On the other hand, when we introduce the bond-disorder in a regular fashion, the system follows the dynamical scaling for the modest number of disordered sites. For a higher number of disordered sites, the evolution morphology illustrates a lamellar pattern formation. Our MC results are consistent with the Lifshitz-Slyozov power-law growth in all the cases.
Exergy in near-field electromagnetic heat transfer
Authors: Iizuka Hideo , Fan Shanhui
Published: September 2017

The maximum amount of usable work extractable from a given radiative heat flow defines the exergy. It was recently noted that the exergy in near-field radiative heat transfer can exceed that in the far-field. Here, we derive a closed form formula of exergy in the near-field heat transfer between two parallel surfaces. This formula reveals that, for a given resonant frequency, the maximum exergy depends critically on the resonant linewidth, and there exists an optimal choice of the linewidth that maximizes the exergy. Guided by the analytical result, we show numerically that with a proper choice of doping concentration, the heat flow between two properly designed SiC-coated heavily doped silicon regions can possess exergy that is significantly higher compared to the heat flow between two SiC regions where the heat flow is carried out by phonon-polaritons. Our work indicates significant opportunities for either controlling material properties or enhancing the fundamental potential for near-field heat transfer in thermal energy conversion through the approach of meta-material engineering.
Negative differential resistance and resistive switching in SnO2/ZnO interface
Authors: Pant Rohit , Patel Nagabhushan , Nanda K. K. , Krupanidhi S. B.
Published: September 2017

We report a very stable negative differential resistance (NDR) and resistive switching (RS) behavior of highly transparent thin films of the SnO2/ZnO bilayer, deposited by magnetron sputtering. When this bilayer of SnO2/ZnO was annealed at temperatures above 400 °C, ZnO diffuses into SnO2 at the threading dislocations and gaps between the grain boundaries, leading to the formation of a ZnO nanostructure surrounded by SnO2. Such a configuration forms a resonant tunneling type structure with SnO2/ZnO/SnO2…….ZnO/SnO2 interface formation. Interestingly, the heterostructure exhibits a Gunn diode-like behavior and shows NDR and RS irrespective of the voltage sweep direction, which is the characteristic of unipolar devices. A threshold voltage of ∼1.68 V and a peak-to-valley ratio of current ∼2.5 are observed for an electrode separation of 2 mm, when the bias is swept from −5 V to +5 V. It was also observed that the threshold voltage can be tuned with changing distance between the electrodes. The device shows a very stable RS with a uniform ratio of about 3.4 between the high resistive state and the low resistive state. Overall, the results demonstrate the application of SnO2/ZnO bilayer thin films in transparent electronics.
The effects of PbZn1/3Nb2/3O3-doping on structural, thermal, optical, dielectric, and ferroelectric properties of BaTiO3 ceramics
Authors: Suchanicz J. , Świerczek K. , Sitko D. , Czaja P. , Marchet P. , Czternastek H. , Majda D.
Published: September 2017

Low-lead (1-x)BT-xPZN (x = 0, 0.025, 0.05, 0.075, 0.10, 0.125, and 0.15) ceramics were successfully synthesized by the spark-plasma-sintering method for the first time. Their phase transition behavior as well as structural, thermal, optical, and electrical properties was investigated. These materials exhibit the structure of perovskite-type solid solutions and undergo a sequence of phase transitions, typical of pure BaTiO3 (BT). The dielectric test results revealed that with the increase in the PbZn1/3Nb2/3O3 (PZN) content, the frequency dispersion of electric permittivity increases, whilst the dielectric/ferroelectric properties tend to deteriorate, which is characteristic of relaxor-type behavior. Therefore, it is reasonable to suppose that these ceramics progressively lack long-range ordering. These effects are due to the competition between lone-pair electrons' induced changes in the A-O band upon Pb2+ addition and ionic size differences. In general, the transition temperatures observed by dielectric analyses are in good agreement with those obtained from X-ray diffraction and differential scanning calorimetry measurements. The BT-PZN system may help to understand why relaxor behavior appears in perovskite-based materials. It appears that these materials can become a good starting point for the development of new low-lead electronic ceramics.
Translation, post-editing and directionality
Authors: Lourenço da Silva Igor A. , Alves Fabio , Schmaltz Márcia , Pagano Adriana , Wong Derek , Chao Lidia , Leal Ana Luísa V. , Quaresma Paulo , Garcia Caio , da Silva Gabriel Eduardo
Published: September 2017

Translation process research has focused on alphabetic scripts in post-editing and translation tasks from the second language (L2) into the mother tongue (L1). This chapter approaches translation and post-editing tasks involving Chinese, which has a logographic script, in combination with Portuguese. The aim is to compare task type (translation and post-editing) and directionality (L2-L1 and L1-L2) focusing on cognitive and temporal measures of effort. Eye-tracking and key-logging data were collected from 18 Chinese professional translators in four consecutive translation/post-editing sessions. The results point to a significant impact of directionality and task type on virtually all cognitive measures investigated by means of a linear mixed-effect regression model. However, directionality and task type had no significant impact on total task time.
Intralingual and interlingual translation
Authors: Whyatt Bogusława , Kajzer-Wietrzny Marta , Stachowiak Katarzyna
Published: September 2017

In this chapter we argue that cognitive processing in intralingual transfer and interlingual translation displays a substantial overlap in the way decisions are made. Since this theoretical claim has rarely been empirically validated, a comparative analysis of both processes is very much needed to pinpoint the similarities and differences between the cognitive effort needed to translate a text and to provide its intralingual paraphrase, for example in the form of a more reader friendly version. This aim motivated us to design the ParaTrans project in which we apply technologically advanced translation process tools, such as key-logging, eye-tracking and screen recording to collect user activity data. We discuss the methodological considerations needed to ensure the validity of the research design and reliability of its findings and report results of a preliminary study.
Quality is in the eyes of the reviewer
Authors: Guerberof Ana
Published: September 2017

As part of a larger research project exploring correlations between productivity, quality and experience in the post-editing of machine-translated and translation-memory outputs in a team of 24 professional translators, three reviewers were asked to review the translations/post-editions completed by these translators and to fill in the corresponding quality evaluation forms. The data obtained from the three reviewers’ evaluation was analysed in order to determine if there was agreement in terms of time as well as in number and type of errors marked to complete the task. The results show that there were statistically significant differences between reviewers, although there were also correlations on pairs of reviewers depending on the provenance of the text analysed. Reviewers tended to agree on the general number of errors found in the No match category but their agreement in Fuzzy and MT match was either weak or there was no agreement, perhaps indicating that the origin of the text might have influenced their evaluation. The reviewers also tended to agree on best and worst performers, but there was great disparity in the translators’ classifications if they were ranked according to the number of errors.
How do social networks influence children’s stylistic practices?
Authors: Buson Laurence
Published: September 2017

Studying children’s ability to construct themselves as pluristyle speakers goes hand-in-hand with studying their socialisation. Children’s conversational experiences are one of the key factors that allow them to integrate and participate in social life. This article will therefore present studies conducted in a school setting with the aim of better understanding the links between children’s stylistic usage and the social diversity of their social networks. The network approach has been widely used in adults but rarely with children and it allows the acquisition of variation to be considered in context, taking into account children’s horizontal socialisation beyond parental influences.

The present analysis will begin by looking briefly at existing work drawing on the notion of social networks in adults and teenagers in order to outline a number of related key research questions in terms of first-language acquisition. Some results obtained from a study conducted in Grenoble (France) with 10-11-year-old children will then be described (Buson 2009a, b). Finally, micro-sociolinguistic analysis will be used to return to some of the methodological issues that remain to be resolved in order to reach a more detailed understanding of the links between the acquisition of variation and the influence of peer networks.
Acquisition of phonological variables of a Flemish dialect by children raised in Standard Dutch
Authors: Rys Kathy , Keuleers Emmanuel , Daelemans Walter , Gillis Steven
Published: September 2017

This study investigates the learning mechanisms underlying the acquisition of a dialect as a second language. We focus on the acquisition of phonological features of a Flemish dialect by children with Standard Dutch or a regional variety of Dutch as their first language. Data were gathered by means of picture naming and sentence completion tasks. Inspired by Chambers (1992), who found that the data of second dialect learners displayed S-curve patterns which he interpreted as evidence of rule-based learning, we examine whether similar S-curves can be observed in the learner data of our subjects. Contrary to Chambers, our subjects’ data do not display S-curves but bear evidence of word-by-word learning across the board. These data are consistent with analogical memory-based models of language acquisition. In order to further investigate the applicability of memory-based reasoning to our data, we perform a computational classification task in TiMBL (Daelemans & Van den Bosch 2005), in which the dialect forms of Standard Dutch words have to be predicted on the basis of various amounts of training data. Not only do we compare the accuracy scores of the model with the acquisition scores of our subjects, the classification task also gives us insight into which words constitute the nearest neighbours of a given word. On the basis of this output, we investigate the effect of the number of enemy neighbours on the degree to which the subjects realize the correct dialect variants of words and on the degree to which they make overgeneralization errors. The major finding of this paper is that dialect forms are more often realized incorrectly and that more overgeneralization errors occur in words with a large(r) number of enemy neighbours.
Developing of galling during the forming and its improvement by physical vapour depositing
Authors: Zhou Luhai , Gao Kaixiang , Zheng Xiankun , Wang Wurong , Wei Xicheng , Hua Meng
Published: September 2017

In sheet metal stamping, galling is initiated and developed aggressively at the mould radius, where sheet metal undergoes large plastic deformation. This study sheds light on correlating the level of sheet plastic deformation with galling initiation on the mould surface. The 3D topography facilitated the observation of galling evolution process on the surface of quenched/tempered mould. The observation on the sliding sheet counterpart showed that with larger plastic deformation, zinc-coated surface tended to become rough and a large number of intermittent micro-cracks formed, leading to earlier initiation of galling. Furthermore, the surface of mould was treated by physical vapour depositing (PVD) of CrN. In the specific sliding tests under the same level of plastic deformation, critical total slid distance at which galling initiated was increased significantly. The major factor causing galling initiation on the PVD(CrN)-coated mould was identified.