bluuebunny/crossref_metadata_2025 huggingface dataset:
Proximate composition, amino acid profile, carbohydrate and mineral content of seed meals from four safflower (Carthamus tinctoriusL.) varieties grown in north-eastern Morocco
Authors: Mansouri Farid , Ben Moumen Abdessamad , Richard Gaetan , Fauconnier Marie-Laure , Sindic Marianne , Elamrani Ahmed , Serghini Caid Hana
Published: January 2018

The purpose of this study is to complete our work on the characterization of four safflower varieties produced in the oriental region of Morocco by determining the composition of their meals. This characterization was carried out by analyzing proteins, amino acids, fibers, carbohydrates and mineral elements. The results show that the protein content varies in a range of 17.06–27.05%, fibers 63.45–69.97%, carbohydrates 12.40–17.07% and ash 3.11–3.60% on dry weight basis. The most abundant amino acid in the studied safflower meals is glutamic acid (3.19–3.89% of dry matter), while lysine and methionine are the least abundant. Cellulose and hemicellulose are the most representative fibers (28.16–31.35% and 21.04–21.68% of dry matter, respectively). The main carbohydrate is xylose, whose content varies between 10.56–14.31% of dry matter. The results also show that the studied safflower meals constitute a good source of potassium (6.32–9.51 g kg−1of dry matter), phosphorus (2.35–4.60 g kg−1), magnesium (2.25–4.25 g kg−1) and calcium (1.53–1.72 g kg−1). Amongst the identified microelements, iron is the major element in all the analyzed samples (53–125 mg kg−1). Moreover, the majority of the studied analytical parameters were strongly influenced by the cultivar factor (p < 0.05). In view of these analyses and pasture shortage, especially during the dry seasons in Morocco, the meal obtained from oil extraction from safflower seeds can be upgraded by the formulation of new animal feed products in this region.
La précision des empreintes numériques intra-orales en orthodontie est-elle suffisante ?
Authors: Duvert Romain , Gebeile-Chauty Sarah
Published: January 2018

Introduction : Le remplacement des empreintes par des caméras intra-orales constitue un changement de paradigme. Mais aucune étude in vivo indépendante n'a encore comparé la précision des empreintes analogiques avec celle de trois systèmes d'empreintes numériques. La précision des empreintes par caméra intra-orale est-elle suffisante pour notre usage orthodontique ? Matériels et méthodes : Cinq empreintes de l'arcade maxillaire et mandibulaire d'un même sujet ont été réalisées en vinylpolysiloxane, coulées en plâtre de type IV puis numérisées par un scanner de laboratoire (groupe VPS). Un modèle en plâtre (maxillaire et mandibulaire) constitue la référence. Cinq numérisations de l'arcade maxillaire et mandibulaire du modèle référence (groupe EXO) et du sujet en intra-oral (groupe INTRA) ont été réalisées successivement par les caméras Lythos™ (Ormco) version 1, iTero® (AlignTech) version 1 et Trios® (3shape) version 2. Les modèles numériques de chaque groupe ont été découpés puis superposés par technique Best Fit aux modèles références. Résultats : Les images du groupe INTRA présentent une précision inférieure de 18 μm (p = 3,88 10−08) par rapport aux images du groupe EXO et VPS. L'arcade maxillaire présente une fidélité supérieure de 6 μm par rapport à l'arcade mandibulaire pour les trois systèmes (p = 0,002). La technique de prise d'empreinte (analogique ou numérique) et le modèle de caméra – malgré une différence sur le nombre de points enregistrés – n'a pas d'influence statistiquement significative sur la précision. Conclusion : Effectuée dans les conditions idéales, la précision des caméras, certes inférieure aux empreintes classiques VPS, est suffisante pour un usage clinique. Cependant, la réduction du temps d'acquisition risque d'affecter cette précision, lisser les erreurs et contracter les arcades.
Autotransplantation d'une incisive maxillaire et prise en charge orthodontique : à propos d'un cas
Authors: Charpentier Valentine , Makaremi Masrour , Brondeau François de
Published: January 2018

Introduction : Les incisives sévèrement incluses avec une anatomie radiculaire atypique ne répondent pas favorablement à la traction orthodontique après exposition chirurgicale. Par conséquent, elles sont souvent extraites et leur moyen de remplacement prothétique se trouve très limité chez les patients en croissance. L'autotransplantation apparaît alors comme l'unique méthode de conserver la dent naturelle et de préserver l'os alvéolaire dentaire. Matériels et méthodes : Une incisive centrale maxillaire bloquée dans la région des fosses nasales avec un apex ouvert a été diagnostiquée chez une patiente de 8 ans et demi. La dent présentait une courbure radiculaire contre la corticale de l'os maxillaire, contrariant sa traction orthodontique. À travers ce cas clinique d'autotransplantation d'une incisive maxillaire et d'une revue de la littérature, cet article explore les indications et expose les différentes étapes de cette thérapeutique orthodontico-chirurgicale. Résultats : L'autotransplantation a permis dans ce cas la restauration de la continuité de l'arcade après un temps de traitement orthodontique de deux années. La reconstruction osseuse du site d'extraction a été très satisfaisante. Discussion : Les intérêts de cette technique et les précautions à prendre sont discutés, ainsi que les différents protocoles de mise en œuvre. Son taux de succès croissant permet de considérer cette pratique chirurgicale comme un protocole d'avenir.
Validation of Three Postoperative Risk Prediction Models for Intensive Care Unit Mortality after Cardiac Surgery
Authors: Caiado Camila , McCollum Charles , Goldstein Michael , Malagon Ignacio , Venkateswaran Rajamiyer , Grant Stuart , Howitt Samuel
Published: January 2018

Background Several cardiac surgery risk prediction models based on postoperative data have been developed. However, unlike preoperative cardiac surgery risk prediction models, postoperative models are rarely externally validated or utilized by clinicians. The objective of this study was to externally validate three postoperative risk prediction models for intensive care unit (ICU) mortality after cardiac surgery.

Methods The logistic Cardiac Surgery Scores (logCASUS), Rapid Clinical Evaluation (RACE), and Sequential Organ Failure Assessment (SOFA) scores were calculated over the first 7 postoperative days for consecutive adult cardiac surgery patients between January 2013 and May 2015. Model discrimination was assessed using receiver operating characteristic curve analyses. Calibration was assessed using the Hosmer–Lemeshow (HL) test, calibration plots, and observed to expected ratios. Recalibration of the models was performed.

Results A total of 2255 patients were included with an ICU mortality rate of 1.8%. Discrimination for all three models on each postoperative day was good with areas under the receiver operating characteristic curve of >0.8. Generally, RACE and logCASUS had better discrimination than SOFA. Calibration of the RACE score was better than logCASUS, but ratios of observed to expected mortality for both were generally <0.65. Locally recalibrated SOFA, logCASUS and RACE models all performed well.

Conclusion All three models demonstrated good discrimination for the first 7 days after cardiac surgery. After recalibration, logCASUS and RACE scores appear to be most useful for daily risk prediction after cardiac surgery. If appropriately calibrated, postoperative cardiac surgery risk prediction models have the potential to be useful tools after cardiac surgery.
Osteoporotische Wirbelkörperfraktur
Authors: Hartensuer René , Raschke Michael
Published: January 2018

Die Osteoporose ist ein zunehmendes Problem der muskuloskeletalen Medizin. Neben einer zunehmenden Inzidenz im Alter ist ein weiteres epidemiologisches Phänomen zu beobachten. Aktuell werden im höheren Alter zunehmend komplexere Verletzungsmuster beschrieben. Eine Osteoporose kann also zum einen zu Spontanfrakturen (Sinterung) führen, zum anderen als koinzidenteller Faktor von Bagatelltraumen wie auch von „echten“ traumatischen (hochenergetischen) Verletzungen auftreten. Die diagnostischen Möglichkeiten, zwischen diesen Entitäten zu unterscheiden, stellen den Behandler hierbei vor eine gewisse Herausforderung. Eine valide Klassifikation, die den Besonderheiten der Verletzungen der osteoporotischen Wirbelsäule Rechnung trägt, ist leider noch nicht etabliert. Die prinzipiellen Behandlungsziele und -prinzipien unterscheiden sich bei den Wirbelkörperfrakturen bei Osteoporose nicht wesentlich von den sonstigen Prinzipien beim Knochengesunden. Dennoch bietet die osteoporotische Wirbelsäule besondere Herausforderungen. Hierbei besteht die Möglichkeit, den Wirbelkörper selbst zu stabilisieren. Dies erfolgt oft kombiniert mit einer intravertebralen Aufrichtung und dem Einfüllen von PMMA oder alternativen Substanzen. Weiter kann mittels Pedikelschrauben das Bewegungssegment stabilisiert werden. Der Halt der Schrauben im Wirbelkörper kann hierbei ebenfalls mit PMMA verbessert werden. Eine ventrale Abstützung kann entweder durch einen weiteren ventralen Eingriff oder über eine Kombination von augmentierenden Verfahren des frakturierten Wirbelkörpers mit der dorsalen Instrumentierung erreicht werden. Diese mannigfaltigen therapeutischen Möglichkeiten erfordern ein differenziertes Vorgehen. Letztlich darf bei jeglicher chirurgischen Therapie die Behandlung der Grunderkrankung Osteoporose nicht vergessen werden.
Discordance in steatosis classification between liver biopsy and transient elastography for high controlled attenuation parameter (CAP) values
Authors: Galaski Johanna , Schulz Lisa , Krause Jenny , Lohse Ansgar
Published: January 2018

Objective The controlled attenuation parameter (CAP) measured by transient elastography allows for the noninvasive assessment of hepatic steatosis. However, discrepant results between CAP values and histological evaluation have been reported in particular with high CAP values. We therefore investigated the diagnostic validity of high CAP measurements.

Methods Forty patients with liver disease and CAP measurements > 300 dB/m that underwent ultrasound-guided or minilaparoscopic liver biopsy were retrospectively enrolled. CAP values were compared with the respective histological and macroscopic evaluation and correlated with clinical parameters.

Results CAP values > 300 dB/m had an 87.5 % specificity for detection of hepatic steatosis but failed to discriminate between steatosis grade S1 – S3. Discordant results, defined as a discrepancy of at least 2 steatosis grades between transient elastography and liver biopsy, were observed in 40 % of cases. The interquartile range (IQR) of CAP was confirmed as a predictor of discrepant findings. Macroscopic evaluation as part of minilaparoscopy detected hepatic steatosis in 74 % of patients with histological grade S2 – S3 in contrast to only 10 % classified as histological grade S0 – S1.

Conclusion High CAP measurements need to be interpreted with care and with regard to clinical parameters, in particular when high IQR values are registered.
Versorgung bei kompensierter Leberzirrhose 2018 – Evidenzbasierte prophylaktische Maßnahmen
Authors: Karkmann Kathrin , Piecha Felix , Rünzi Anna , Schulz Lisa , von Wulffen Moritz , Benten Daniel , Kluwe Johannes , Wege Henning
Published: January 2018

In Deutschland starben 2015 mehr als 13 000 Menschen an den Folgen einer Leberzirrhose. Die Diagnose einer fortgeschrittenen Leberschädigung kann häufig mit nicht-invasiven Methoden (z. B. mittels ultraschallbasierter Messung der Steifigkeit des Lebergewebes) bereits im noch kompensierten Stadium gestellt werden. Entscheidend ist bei Diagnosestellung eine umfassende Ursachenabklärung und konsequente Therapie der zugrundeliegenden chronischen Lebererkrankung, um einen weiteren Progress bis zur Dekompensation zu verhindern. Da insbesondere bei einer Dekompensation (angezeigt u. a. durch Ikterus, Aszites, hepatische Enzephalopathie, gastrointestinale Blutung) Morbidität und Mortalität deutlich ansteigen (z. B. steigt die 1-Jahres-Mortalität von 1 – 3,4 % auf 20 – 57 %), sind prophylaktische Maßnahmen zur Vermeidung einer Dekompensation indiziert. Diese Maßnahmen umfassen nach Risikostratifizierung einer portalen Hypertension den Einsatz von Propranolol oder Carvedilol sowie eine endoskopische Ligatur mit Gummibändern zur Primärprophylaxe einer Varizenblutung. Aufgrund des hohen Risikos für eine maligne Transformation (je nach Ätiologie der Leberzirrhose 2 – 8 % pro Jahr), ist auch eine sonografische Überwachung alle sechs Monate zur frühen Diagnose eines Leberzellkarzinoms entscheidend, um eine kurative Therapie zu ermöglichen. Diskutiert wird auch der Einsatz von Antibiotika zur Vermeidung von Infektionen, die in vielen Fällen eine akute Dekompensation auslösen. Hier ist die Datenlage noch nicht überzeugend und das Risiko einer Resistenzbildung ist zu beachten. Unbedingt sollte aber der Impfstatus überprüft und Impflücken geschlossen werden. Zur Versorgung bei kompensierter Leberzirrhose gehören auch eine ernährungsphysiologische Beratung und ggf. medikamentöse Therapien, um das Voranschreiten von Osteoporose und Muskelatrophie aufzuhalten. In diesem Aufsatz werden die einzelnen Maßnahmen zur prophylaktischen Versorgung bei kompensierter Leberzirrhose vorgestellt und vor dem Hintergrund der pathophysiologischen Grundlagen und wegweisender klinischer Studien diskutiert. Sollte es trotz dieser prophylaktischen Maßnahmen zu einer Dekompensation kommen (ca. 15 % der Patienten mit Leberzirrhose jährlich), ist die Indikation zur Lebertransplantation als definitive Therapie der Leberzirrhose zu prüfen (spätestens ab einem MELD-Index > 15).
Applikation intrabronchialer Ventile zur Behandlung der persistierenden bronchopleuralen Fistel nach komplikativem Pleuraempyem mit Lungendestruktion
Authors: Akil Ali , Reichelt Jan , Freermann Stefan , Karfis Ilias , Semik Michael , Fischer Stefan
Published: January 2018

Hintergrund Die chirurgische Therapie persistierender bronchopleuraler Fisteln (BPF) kann sich insbesondere aufgrund von rezidivierenden Infekten langwierig gestalten. Als Alternative zur chirurgischen Versorgung steht die intrabronchiale Ventilimplantation zur Verfügung. Hier werden unsere Erfahrungen mit dem Einsatz intrabronchialer Ventilen bei Hochrisikopatienten mit persistierender BPF dargestellt.

Material und Methoden Von April 2015 bis März 2017 wurden bei insgesamt 8 Patienten (n = 4 weiblich) mit komplikativem Pleuraempyem und begleitender Lungendestruktion, die eine persistierende BPF entwickelt hatten, intrabronchiale Ventile eingebracht. Die persistierende BPF konnte sowohl bronchoskopisch als auch CT-grafisch dargestellt werden. Die Ventile wurden via flexibler Bronchoskopie eingebracht. Bei n = 6 Patienten wurde aufgrund wiederholter Keimnachweise und persistierenden Infekten ein temporäres Thorakostoma angelegt.

Ergebnisse Das mittlere Alter betrug 61 Jahre (45 – 85 Jahre). In allen Fällen konnte die BPF mit intrabronchialen Ventilen okkludiert werden. Nach erfolgreicher Infektsanierung wurden alle Thorakostomata verschlossen. Bei 1 Patientin musste eine Thorakoplastik durchgeführt werden. Zur Therapie der persistierenden BPFs wurden durchschnittlich n = 3 Ventile platziert (1 – 4 Ventile). Bei allen Patienten verlief die Ventilplatzierung komplikationsfrei. Thoraxdrainagen konnten bei ausbleibender Luftfistelung und radiologisch kompletter Entfaltung der Lunge nach durchschnittlich 7 Tagen (3 – 15 Tagen) entfernt werden. Der mittlere Krankenhausaufenthalt nach Ventilimplantation lag bei 10 Tagen (5 – 20 Tagen). Komplikationen traten auch in der Nachbeobachtung nicht auf. Bei 2 Patienten wurden die Ventile bereits nach 6 Monaten entfernt. Die nachfolgenden Kontrollen zeigten weiterhin eine komplette Entfaltung der Lunge. Alle Patienten leben bis dato.

Schlussfolgerung Die intrabronchiale Ventilimplantation ist ein sicheres und wirksames Verfahren zur Behandlung von Patienten mit persistierender BPF auf dem Boden von rezidivierenden thorakalen Infekten mit begleitender Lungendestruktion. Insbesondere bei Patienten mit hohem operativem Risiko kann diese Therapie als Alternative zur chirurgischen Intervention mehr in Betracht gezogen werden.
The Effects of Folate Supplementation on Diabetes Biomarkers Among Patients with Metabolic Diseases: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Authors: Akbari Maryam , Tabrizi Reza , Lankarani Kamran B. , Heydari Seyed Taghi , Karamali Maryam , Keneshlou Fariba , Niknam Kayvan , Kolahdooz Fariba , Asemi Zatollah
Published: January 2018

Although several studies have evaluated the effect of folate supplementation on diabetes biomarkers among patients with metabolic diseases, findings are inconsistent. This review of randomized controlled trials (RCTs) was performed to summarize the evidence on the effects of folate supplementation on diabetes biomarkers among patients with metabolic diseases. Randomized-controlled trials (RCTs) published in PubMed, EMBASE, Web of Science and Cochrane Library databases up to 1 September 2017 were searched. Two review authors independently assessed study eligibility, extracted data, and evaluated risk of bias of included studies. Heterogeneity was measured with a Q-test and with I2 statistics. Data were pooled by using the fix or random-effect model based on the heterogeneity test results and expressed as standardized mean difference (SMD) with 95% confidence interval (CI). A total of sixteen randomized controlled trials involving 763 participants were included in the final analysis. The current meta-analysis showed folate supplementation among patients with metabolic diseases significantly decreased insulin (SMD –1.28; 95% CI, –1.99, –0.56) and homeostasis model assessment of insulin resistance (HOMA-IR) (SMD –1.28; 95% CI, –1.99, –0.56). However, folate supplementation did not affect fasting plasma glucose (FPG) (SMD –0.30; 95% CI, –0.63, 0.02) and hemoglobin A1C (HbA1c) (SMD –0.29; 95% CI, –0.61, 0.03). The results of this meta-analysis study demonstrated that folate supplementation may result in significant decreases in insulin levels and HOMA-IR score, but does not affect FPG and HbA1c levels among patients with metabolic diseases.
Photonic nanojet assisted enhancement of Raman signal: Effect of refractive index contrast
Authors: Patel H. S. , Kushwaha P. K. , Swami M. K.
Published: January 2018

We discuss the enhancement of Raman signals using a photonic nanojet generated by dielectric microspheres. The highly confined field of the nanojet leads to an order of magnitude enhancement of the Raman signal from the substrate beneath. Enhancement is observed to depend strongly on the sizes of the microspheres as well as the contrast between their refractive index and that of the sample. Enhancement increases when the refractive index of the substrate increases relative to that of the microsphere, but decreases rapidly as the two become equivalent.
Accounting for Debye sheath expansion for proud Langmuir probes in magnetic confinement fusion plasmas
Authors: Tsui C. K. , Boedo J. A. , Stangeby P. C. ,   TCV Team
Published: January 2018

A Child-Langmuir law-based method for accounting for Debye sheath expansion while fitting the current-voltage I-V characteristic of proud Langmuir probes (electrodes that extend into the volume of the plasma) is described. For Langmuir probes of a typical size used in tokamak plasmas, these new estimates of electron temperature and ion saturation current density values decreased by up to 60% compared to methods that did not account for sheath expansion. Changes to the collection area are modeled using the Child-Langmuir law and effective expansion perimeter lp, and the model is thus referred to as the “perimeter sheath expansion method.” lp is determined solely from electrode geometry, so the method may be employed without prior measurement of the magnitude of the sheath expansion effects for a given Langmuir probe and can be used for electrodes of different geometries. This method correctly predicts the non-saturating ΔI/ΔV slope for cold, low-density plasmas where sheath-expansion effects are strong, as well as for hot plasmas where ΔI/ΔV ∼ 0, though it is shown that the sheath can still significantly affect the collection area in these hot conditions. The perimeter sheath expansion method has several advantages compared to methods where the non-saturating current is fitted: (1) It is more resilient to scatter in the I-V characteristics observed in turbulent plasmas. (2) It is able to separate the contributions to the ΔI/ΔV slope from sheath expansion to that of the high energy electron tail in high Te conditions. (3) It calculates the change in the collection area due to the Debye sheath for conditions where ΔI/ΔV ∼ 0 and for V = Vf.
Temperature dependence of reduced offset in double Hall sensor structure reducing voltage offset
Authors: Oszwaldowski M. , El-Ahmar S.
Published: January 2018

We have recently described the principle of operation of a double Hall sensor structure (DHSS) reducing the voltage offset [M. Oszwałdowski and S. El-Ahmar, Rev. Sci. Instrum. 88, 075005 (2017)]. The correctness of operation of the structure and its characteristic features were checked and clarified experimentally using the structures made of InSb thin films. In the present paper, we investigate the very important problem of the temperature dependence of the reduced offset in the DHSS. We show that the reduced voltage temperature dependence is entirely governed by the temperature dependence of the resistance of the component Hall sensors. If the averaged temperature dependence of the resistance of both the component Hall sensors were the same in a given temperature range, the reduced offset of the DHSS can be virtually independent of temperature in that temperature range. This behavior is confirmed by experimental investigations performed on DHSSs made of InSb thin films.
Flexible mechanism of magnetic microbeads chains in an oscillating field
Authors: Li Yan-Hom , Yen Chia-Yen
Published: January 2018

To investigate the use of magnetic microbeads for swimming at low Reynolds number, the flexible structure of microchains comprising superparamagnetic microbeads under the influence of oscillating magnetic fields is examined experimentally and theoretically. For a ductile chain, each particle has its own phase angle trajectory and phase-lag angle to the overall field. This present study thoroughly discusses the synchronicity of the local phase angle trajectory between each dyad of beads and the external field. The prominently asynchronous trajectories between the central and outer beads significantly dominate the flexible structure of the oscillating chain. In addition, the dimensionless local Mason number (Mnl) is derived as the solo controlling parameter to evaluate the structure of each dyad of beads in a flexible chain. The evolution of the local Mason number within an oscillating period implies the most unstable position locates near the center of the chain around 0.6P<t<0.8P. Moreover, a chain with a certain length in the influence of the oscillating field would behave the most significant deformation and have the most flexible structure.
Physical origins of temperature continuity at an interface between a crystal and its melt
Authors: Vo Truong Quoc , Kim BoHung
Published: January 2018

We justify and discuss the physical origins for the assumption of temperature continuity at crystal/melt interfaces by performing atomistic simulations. We additionally answer why the crystal/melt interfaces differ from the typical solid/liquid interfaces, which usually exhibit dissimilarities and a resulting temperature drop. We present results for pure silver modeled using the embedded-atom method and Lennard-Jones potential function and contrast the results with each other. We find that the temperature continuity at an interface between a crystal and its melt originates from the perfect vibrational coupling, which is caused by the interfacial structural diffusivity. This study provides fundamental insights into the heat transfer for cases of extremely large heat flux and thermal gradients occurring during rapid melting and solidification. The findings additionally determine the role of rough surfaces in manipulating the thermal conductance in nanodevices.
Physics of self-aligned assembly at room temperature
Authors: Dubey V. , Beyne E. , Derakhshandeh J. , De Wolf I.
Published: January 2018

Self-aligned assembly, making use of capillary forces, is considered as an alternative to active alignment during thermo-compression bonding of Si chips in the 3D heterogeneous integration process. Various process parameters affect the alignment accuracy of the chip over the patterned binding site on a substrate/carrier wafer. This paper discusses the chip motion due to wetting and capillary force using a transient coupled physics model for the two regimes (that is, wetting regime and damped oscillatory regime) in the temporal domain. Using the transient model, the effect of the volume of the liquid and the placement accuracy of the chip on the alignment force is studied. The capillary time (that is, the time it takes for the chip to reach its mean position) for the chip is directly proportional to the placement offset and inversely proportional to the viscosity. The time constant of the harmonic oscillations is directly proportional to the gap between the chips due to the volume of the fluid. The predicted behavior from transient simulations is next experimentally validated and it is confirmed that the liquid volume and the initial placement affect the final alignment accuracy of the top chip on the bottom substrate. With statistical experimental data, we demonstrate an alignment accuracy reaching <1 μm.
Structure and magnetic properties of L1-MnGa nanoparticles prepared using direct reactions between Mn nanoparticles and Ga
Authors: Si P. Z. , Qian H. D. , Park J. , Ge H. L. , Shinde K. P. , Chung K. C. , Choi C. J.
Published: January 2018

The tetragonal L10-Mn1+xGa (x<0.8) nanoparticles and bcc-Mn23Ga77 nanoparticles with large coercivity were prepared using direct reactions between Mn nanoparticles and Ga at elevated temperatures. The Mn23Ga77 phase was formed at ∼573 K while the L10-structured Mn1+xGa was formed at ∼850 K. After ball-milling, the L10-Mn1+xGa nanoparticles transformed into nano-flakes with enhanced coercivity. The size of the as-prepared Mn23Ga77 nanoparticles is comparable to that of the precursor Mn nanoparticles. An aggregation of the nanoparticles and thus a larger particle size were observed in the L10-Mn1+xGa nanoparticles obtained at 850 K. The size of the L10-Mn1+xGa nano-flakes is reduced to about 200-400 nm with a thickness of ∼20 nm. The coercivity of the Mn23Ga77 nanoparticles and the L10-Mn1+xGa nanoparticles at 300 K reached up to 0.2 T and 0.43 T, respectively. The coercivity of L10-Mn1+xGa ball-milled nano-flakes is 0.59 T at 300 K.
Identifying microturbulence regimes in a TCV discharge making use of physical constraints on particle and heat fluxes
Authors: Mariani A. , Brunner S. , Dominski J. , Merle A. , Merlo G. , Sauter O. , Görler T. , Jenko F. , Told D.
Published: January 2018

Reducing the uncertainty on physical input parameters derived from experimental measurements is essential towards improving the reliability of gyrokinetic turbulence simulations. This can be achieved by introducing physical constraints. Amongst them, the zero particle flux condition is considered here. A first attempt is also made to match as well the experimental ion/electron heat flux ratio. This procedure is applied to the analysis of a particular Tokamak à Configuration Variable discharge. A detailed reconstruction of the zero particle flux hyper-surface in the multi-dimensional physical parameter space at fixed time of the discharge is presented, including the effect of carbon as the main impurity. Both collisionless and collisional regimes are considered. Hyper-surface points within the experimental error bars are found. The analysis is done performing gyrokinetic simulations with the local version of the GENE code, computing the fluxes with a Quasi-Linear (QL) model and validating the QL results with non-linear simulations in a subset of cases.
Vibration and acoustic noise emitted by dry-type air-core reactors under PWM voltage excitation
Authors: Li Jingsong , Wang Shanming , Hong Jianfeng , Yang Zhanlu , Jiang Shengqian , Xia Shichong
Published: January 2018

According to coupling way between the magnetic field and the structural order, structure mode is discussed by engaging finite element (FE) method and both natural frequency and modal shape for a dry-type air-core reactor (DAR) are obtained in this paper. On the basis of harmonic response analysis, electromagnetic force under PWM (Pulse Width Modulation) voltage excitation is mapped with the structure mesh, the vibration spectrum is gained and the consequences represents that the whole structure vibration predominates in the radial direction, with less axial vibration. Referring to the test standard of reactor noise, the rules of emitted noise of the DAR are measured and analyzed at chosen switching frequency matches the sample resonant frequency and the methods of active vibration and noise reduction are put forward. Finally, the low acoustic noise emission of a prototype DAR is verified by measurement.

At the request of the authors, this article is being retracted effective 30 October 2018.
Experimental and numerical investigations of electron characteristics in 2 MHz and 13.56 MHz inductively coupled hydrogen plasmas with an expansion region
Authors: Gao Fei , Li Hong , Yang Wei , Liu Jia , Zhang Yu-Ru , Wang You-Nian
Published: January 2018

The electron characteristics are investigated in 2 MHz and 13.56 MHz inductively coupled hydrogen discharges with an expansion region. The influence of the gas pressure and radio-frequency of the power source on the electron energy probability functions (EEPFs), electron density, and electron temperature at high deposition power has been presented. The measured EEPFs in the driver region of the discharge evolve from a three-temperature Maxwellian distribution to a Maxwellian distribution as the pressure increases. Different characteristic frequencies calculated based on the measured plasma parameters show that stochastic heating of electrons dominates at pressures lower than 0.3 Pa and it has to be considered for pressures lower than 1.0 Pa, while Ohmic heating dominates at higher pressure. Furthermore, the EEPFs as a function of the total energy evolve from the identical shape to discrete shapes with axial position and pressure, indicating a transition of electron kinetics from nonlocal to local regimes. This can be explained by the calculated electron energy relaxation length. In order to verify the experimental results, COMSOL Multiphysics is used to calculate the electron density and electron temperature at different pressures and frequencies of power source. The simulated axial distributions of the plasma parameters agree well with the measured results at 5.0 Pa, while the calculated electron density is lower and the calculated electron temperature is higher at 1.0 Pa. In addition, there is no frequency dependence of axial resolved EEPFs, electron density, and electron temperature in high power deposition discharges (1.5 kW).
Study of ion beam sputtered Fe/Si interfaces as a function of Si layer thickness
Authors: Kumar Anil , Brajpuriya Ranjeet , Singh Priti
Published: January 2018

The exchange interaction in metal/semiconductor interfaces is far from being completely understood. Therefore, in this paper, we have investigated the nature of silicon on the Fe interface in the ion beam deposited Fe/Si/Fe trilayers keeping the thickness of the Fe layers fixed at 3 nm and varying the thickness of the silicon sandwich layer from 1.5 nm to 4 nm. Grazing incidence x-ray diffraction and atomic force microscopy techniques were used, respectively, to study the structural and morphological changes in the deposited films as a function of layer thickness. The structural studies show silicide formation at the interfaces during deposition and better crystalline structure of Fe layers at a lower spacer layer thickness. The magnetization behavior was investigated using magneto-optical Kerr effect, which clearly shows that coupling between the ferromagnetic layers is highly influenced by the semiconductor spacer layer thickness. A strong antiferromagnetic coupling was observed for a value of tSi = 2.5 nm but above this value an unexpected behavior of hysteresis loop (step like) with two coercivity values is recorded. For spacer layer thickness greater than 2.5 nm, an elemental amorphous Si layer starts to appear in the spacer layer in addition to the silicide layer at the interfaces. It is observed that in the trilayer structure, Fe layers consist of various stacks, viz., Si doped Fe layers, ferromagnetic silicide layer, and nonmagnetic silicide layer at the interfaces. The two phase hysteresis loop is explained on the basis of magnetization reversal of two ferromagnetic layers, independent of each other, with different coercivities. X-ray photo electron spectroscopy technique was also used to study interfaces characteristics as a function of tSi.
The tunneling potential for field emission from nanotips
Authors: Biswas Debabrata , Ramachandran Rajasree , Singh Gaurav
Published: January 2018

In the quasi-planar approximation of field emission, the potential energy due to an external electrostatic field E0 is expressed as −eγE0Δs, where Δs is the perpendicular distance from the emission site and γ is the local field enhancement factor on the surface of the emitter. We show that for curved emitter tips, the current density can be accurately computed if terms involving (Δs/R2)2 and (Δs/R2)3 are incorporated in the potential where R2 is the second (smaller) principle radius of curvature. The result is established analytically for the hemiellipsoid and hyperboloid emitters, and it is found that for sharply curved emitters, the expansion coefficients are equal and coincide with that of a sphere. The expansion seems to be applicable to generic emitters as demonstrated numerically for an emitter with a conical base and quadratic tip. The correction terms in the potential are adequate for Ra⪆2 nm for local field strengths of 5 V/nm or higher. The result can also be used for nano-tipped emitter arrays or even a randomly placed bunch of sharp emitters.
Self-positioning ability of a sphericon-shaped magnetic millirobot rolling on an inclined surface
Authors: Jeon Seungmun
Published: January 2018

This paper introduces the novel self-positioning ability of a sphericon-shaped magnetic millirobot (SSMM) on an inclined surface. The SSMM is comprised of four identical half cones with a cylindrical magnet inserted into the geometric center, and it can roll along a straight line on a surface with repeated rolling cone motions actuated by an external wobbling magnetic field (EWMF). Due to the restoring moment induced by a conservative gravitational force, the SSMM can maintain (self-position) its equilibrium position on the surface, even when the EWMF is removed. This paper derived several equations to quantify the condition in which the SSMM can steadily generate self-positioning motions. It also examined the self-positioning ability of the SSMM by constructing a prototype SSMM and demonstrating its rolling and self-positioning motions by using a magnetic navigation system.
Formic acid dimers in a nitrogen matrix
Authors: Lopes Susy , Fausto Rui , Khriachtchev Leonid
Published: January 2018

Formic acid (HCOOH) dimers are studied by infrared spectroscopy in a nitrogen matrix and by ab initio calculations. We benefit from the use of a nitrogen matrix where the lifetime of the higher-energy (cis) conformer is very long (∼11 h vs. 7 min in an argon matrix). As a result, in a nitrogen matrix, a large proportion of the cis conformer can be produced by vibrational excitation of the lower-energy (trans) conformer. Three trans-trans, four trans-cis, and three cis-cis dimers are found in the experiments. The spectroscopic information on most of these dimers is enriched compared to the previous studies in an argon matrix. The cis-cis dimers of ordinary formic acid (without deuteration) are reported here for the first time. Several conformational processes are obtained using selective excitation by infrared light, some of them also for the first time. In particular, we report on the formation of cis-cis dimers upon vibrational excitation of trans-cis dimers. Tunneling decays of several dimers have been detected in the dark. The tunneling decay of cis-cis dimers of formic acid as well as the stabilization of cis units in cis-cis dimers is also observed for the first time.
Optical absorption edge broadening in thick InGaN layers: Random alloy atomic disorder and growth mode induced fluctuations
Authors: Butté Raphaël , Lahourcade Lise , Uždavinys Tomas Kristijonas , Callsen Gordon , Mensi Mounir , Glauser Marlene , Rossbach Georg , Martin Denis , Carlin Jean-François , Marcinkevičius Saulius , Grandjean Nicolas
Published: January 2018

To assess the impact of random alloying on the optical properties of the InGaN alloy, high-quality InxGa1−xN (0 < x < 0.18) epilayers grown on c-plane free-standing GaN substrates are characterized both structurally and optically. The thickness (25–100 nm) was adjusted to keep these layers pseudomorphically strained over the whole range of explored indium content as checked by x-ray diffraction measurements. The evolution of the low temperature optical absorption (OA) edge linewidth as a function of absorption energy, and hence the indium content, is analyzed in the framework of the random alloy model. The latter shows that the OA edge linewidth should not markedly increase above an indium content of 4%, varying from 17 meV to 30 meV for 20% indium. The experimental data initially follow the same trend with, however, a deviation from this model for indium contents exceeding only ∼2%. Complementary room temperature near-field photoluminescence measurements carried out using a scanning near-field optical microscope combined with simultaneous surface morphology mappings reveal spatial disorder due to growth meandering. We conclude that for thick high-quality pseudomorphic InGaN layers, a deviation from pure random alloying occurs due to the interplay between indium incorporation and longer range fluctuations induced by the InGaN step-meandering growth mode.
Novel stable structure of Li3PS4 predicted by evolutionary algorithm under high-pressure
Authors: Iikubo S. , Shimoyama K. , Kawano S. , Fujii M. , Yamamoto K. , Matsushita M. , Shinmei T. , Higo Y. , Ohtani H.
Published: January 2018

By combining theoretical predictions and in-situ X-ray diffraction under high pressure, we found a novel stable crystal structure of Li3PS4 under high pressures. At ambient pressure, Li3PS4 shows successive structural transitions from γ-type to β-type and from β-type to α type with increasing temperature, as is well established. In this study, an evolutionary algorithm successfully predicted the γ-type crystal structure at ambient pressure and further predicted a possible stable δ-type crystal structures under high pressure. The stability of the obtained structures is examined in terms of both static and dynamic stability by first-principles calculations. In situ X-ray diffraction using a synchrotron radiation revealed that the high-pressure phase is the predicted δ-Li3PS4 phase.
Enhancement of average thermoelectric figure of merit by increasing the grain-size of Mg3.2Sb1.5Bi0.49Te0.01
Authors: Kanno Tsutomu , Tamaki Hiromasa , Sato Hiroki K. , Kang Stephen Dongmin , Ohno Saneyuki , Imasato Kazuki , Kuo Jimmy Jiahong , Snyder G. Jeffrey , Miyazaki Yuzuru
Published: January 2018

Zintl compound n-type Mg3(Sb,Bi)2 was recently found to exhibit excellent thermoelectric figure of merit zT (∼1.5 at around 700 K). To improve the thermoelectric performance in the whole temperature range of operation from room temperature to 720 K, we investigated how the grain size of sintered samples influences electronic and thermal transport. By increasing the average grain size from 1.0 μm to 7.8 μm, the Hall mobility below 500 K was significantly improved, possibly due to suppression of grain boundary scattering. We also confirmed that the thermal conductivity did not change by increasing the grain size. Consequently, the sample with larger grains exhibited enhanced average zT. The calculated efficiency of thermoelectric power generation reaches 14.5% (ΔT = 420 K), which is quite high for a polycrystalline pristine material.
Head flying characteristics in heat assisted magnetic recording considering various nanoscale heat transfer models
Authors: Hu Yueqiang , Wu Haoyu , Meng Yonggang , Wang Yu , Bogy David
Published: January 2018

The thermal issues in heat-assisted magnetic recording (HAMR) technology have drawn much attention in the recent literature. In this paper, the head flying characteristics and thermal performance of a HAMR system during the touch-down process considering different nanoscale heat transfer models across the head-disk interface are numerically studied. An optical-thermal-mechanical coupled model is first described. The coupling efficiency of the near field transducer is found to be dependent on the head disk clearance. The shortcomings of a constant disk-temperature model are investigated, which reveals the importance of considering the disk temperature as a variable. A study of the head flying on the disk is carried out using an air conduction model and additional near-field heat transfer models. It is shown that when the head disk interface is filled with a solid material caused by the laser-induced accumulation, the heat transfer coefficient can become unexpectedly large and the head's temperature can rise beyond desirable levels. Finally, the additional head protrusion due to the laser heating is investigated.
Transport coefficients in high-temperature ionized air flows with electronic excitation
Authors: Istomin V. A. , Oblapenko G. P.
Published: January 2018

Transport coefficients are studied in high-temperature ionized air mixtures using the modified Chapman–Enskog method. The 11-component mixture N2/N2+/N/N+/O2/O2+/O/O+/NO/NO+/e−, taking into account the rotational and vibrational degrees of freedom of molecules and electronic degrees of freedom of both atomic and molecular species, is considered. Using the PAINeT software package, developed by the authors of the paper, in wide temperature range calculations of the thermal conductivity, thermal diffusion, diffusion, and shear viscosity coefficients for an equilibrium ionized air mixture and non-equilibrium flow conditions for mixture compositions, characteristic of those in shock tube experiments and re-entry conditions, are performed. For the equilibrium air case, the computed transport coefficients are compared to those obtained using simplified kinetic theory algorithms. It is shown that neglecting electronic excitation leads to a significant underestimation of the thermal conductivity coefficient at temperatures higher than 25 000 K. For non-equilibrium test cases, it is shown that the thermal diffusion coefficients of neutral species and the self-diffusion coefficients of all species are strongly affected by the mixture composition, while the thermal conductivity coefficient is most strongly influenced by the degree of ionization of the flow. Neglecting electronic excitation causes noticeable underestimation of the thermal conductivity coefficient at temperatures higher than 20 000 K.
Topological optical isolator based on polariton graphene
Authors: Solnyshkov D. D. , Bleu O. , Malpuech G.
Published: January 2018

We propose a scheme of a topological optical isolator based on the quantum anomalous Hall effect with strongly coupled exciton-polaritons in a patterned GaAs cavity. We study the practical properties of such a device and optimize its parameters. We obtain an isolation ratio of 49 dB at a wavelength of 783 nm for a device of 40 μm with a maximal signal modulation frequency of 300 GHz, operating at temperatures up to 50 K.
Genetic and environmental parameters show associations with essential oil composition in West Australian sandalwood (Santalum spicatum)
Authors: Moniodis Jessie , Renton Michael , Jones Christopher G. , Barbour E. Liz , Byrne Margaret
Published: January 2018

Santalum spicatum (R.Br.) A.DC is a West Australian sandalwood species highly valued for the sesquiterpene-rich oil in mature heartwood. The oil composition, particularly levels of the valuable sesquiterpenoids α- and β-santalol and the allergenic E,E-farnesol, are known to vary across its natural distribution. Our study investigated associations of oil characteristics in 186 S. spicatum trees in semiarid and arid regions of Western Australia with genetic structure, environmental parameters and morphological features. We found associations between oil composition and genetic structure, as well as between oil composition and environmental factors. Analysis of individuals using STRUCTURE revealed two major genetic clusters (K = 2), comprising trees from the arid north clustered together, and the semiarid south-west clustered separately. Mantel tests revealed a significant association between oil characteristics and genetic distance (r = 0.129, P = 0.02). There was considerable variation in the growing environment of S. spicatum. An Adonis test showed a significant association between oil composition and provenance (P = 0.001) and between oil composition and soil type (P = 0.002) but not oil composition and other environmental characters. Soil type was significantly related to santalol and E,E-farnesol content. No significant associations between oil composition and morphological features were identified.
Selecting a location for a primary healthcare facility: combining a mathematical approach with a Geographic Information System to rank areas of relative need
Authors: Dudko Yevgeni , Robey Dennis E. , Kruger Estie , Tennant Marc
Published: January 2018

Geographic Information Systems have become an invaluable tool in many industries as it can help to conceptualise available data and answer questions visually. The software allows for integration of key statistics and geographic data for a more detailed analysis. The objective of this study was to show how mathematically weighted, publicly available, relevant demographics data can be integrated with Geographic Information Systems to identify and rank potential locations for new primary healthcare facilities. Index of Relative Socio-economic Advantage and Disadvantage was mathematically weighted with respect to the usual resident population and the number of people not in the labour force data, at Statistical Area level 1 (SA1). Smoothing was applied by repeating the process at Statistical Area level 2, 3 and 4 to produce a quasi-index of priority. A total of 229 SA1 areas were identified and preselected as potential primary healthcare facility infrastructure sites across Australia. The quasi-index was incorporated into a Geographic Information System to produce a map identifying and ranking areas of relative need. Combining a mathematical approach with Geographic Information Systems can yield significant qualitative and quantitative advantages over conventional methods of site selection.
Topological transformations of Hopf solitons in chiral ferromagnets and liquid crystals
Authors: Tai Jung-Shen B. , Ackerman Paul J. , Smalyukh Ivan I.
Published: January 2018

Significance

While arising in theories in many branches of science, from particle physics to condensed matter and cosmology, stable three-dimensional topological solitons remained experimentally elusive until very recently. We now show that such solitons can be electrically and magnetically switched between states with the same or different Hopf indices. Richness and robustness of this switching promise technological applications in the new breeds of information displays and data storage devices, as well as may provide a test ground and new inspirations for the mathematical knot theory.