bluuebunny/crossref_metadata_2025 huggingface dataset:
CLIPPERS-Syndrom: Eine Erkrankung mit vielen Gesichtern – ein Fallbericht
Authors: Link Tanja Alexandra , Köcher Stephanie Eva , Dohmen Hildegard , Behr Robert , Neumann-Haefelin Tobias
Published: October 2019

Das CLIPPERS-Syndrom ist ein chronisch entzündliches Krankheitsbild des ZNS unklarer Ätiologie, das erstmals 2010 durch die Arbeitsgruppe um Pittock beschrieben wurde. Es ist gekennzeichnet durch typische kernspintomographische Veränderungen, vorwiegend im Hirnstamm, mit entzündlichen perivaskulären, lymphohistiozytären Infiltraten und gutem Ansprechen auf eine Glukokortikoidtherapie. Hier möchten wir den Fall eines damals 40-jährigen Patienten vorstellen, der sich initial mit den typischen klinischen und bildmorphologischen Zeichen eines CLIPPERS-Syndroms vorstellte und unter immunsuppressiver Therapie zunächst eine komplette Remission erzielte. Zwei Jahre später erfolgte eine erneute Vorstellung wegen starker Kopfschmerzen. Das durchgeführte cMRT zeigte erneute, nun konfluierende Läsionen im Kleinhirn. Die erste Hirnbiopsie zeigte eine Lymphoproliferation, erst eine erneute Hirnbiopsie konnte schließlich die vermutete Diagnose eines primären ZNS-Lymphoms stellen.
Nachweis der BRAF-Mutation bei kaninen Prostataerkrankungen
Authors: Grassinger Julia M. , Aupperle-Lellbach Heike , Erhard Hanna , Merz Sophie , Klopfleisch Robert
Published: October 2019

Gegenstand und Ziel In der Literatur konnte in 80 % der Bioptate kaniner Prostatakarzinome (PCa) die BRAF-Mutation nachgewiesen werden. Ziele dieser Arbeit waren, kanine Prostataproben aus dem eigenen Tiergut hinsichtlich des Auftretens der BRAF-Mutation zu untersuchen sowie die Spezifität und Sensitivität des Tests zu evaluieren. Außerdem sollte die Methodik für zytologische Ausstriche etabliert und die Korrelation zwischen der BRAF-Mutation und dem histologischen Bild kaniner PCa dargestellt werden.

Material und Methoden Bioptate (n = 70) und Feinnadelaspirate (n = 17) der Prostata von 87 Hunden wurden histologisch oder zytologisch untersucht. Die Einteilung der Erkrankungen erfolgte wie in der Literatur beschrieben in benigne Prostatahyperplasie (BPH, n = 22), Prostatitis (n = 14), Plattenepithelmetaplasie (PM, n = 2), Atrophie nach Kastration (n = 3) und PCa (n = 46; davon zytologisch nachgewiesen n = 11). Für die PCa wurde der Gleason-Score ermittelt. Zur DNA-Isolierung dienten kommerzielle Testkits. Das Exon 15 wurde mit dem TaqMan® SNP Assay untersucht. Die Spezifität und Sensitivität des Tests wurden berechnet.

Ergebnisse Ein Gleason-Score von 6 und 7 ergab sich in je einem Fall, von 8 bis 10 bei 33 der PCa. Aus allen Proben ließ sich ausreichend DNA isolieren. Die BRAF-Mutation war in 28/46 PCa nachweisbar (Sensitivität 61 %). Bei keinem Hund mit BPH, Prostatitis, PM oder Atrophie wurde die BRAF-Mutation festgestellt (Spezifität 100 %). Durch die BRAF-Mutation verursachte PCa wiesen einen signifikant (p = 0,002) höheren Gleason-Score auf als PCa ohne diese Mutation.

Schlussfolgerung und klinische Relevanz Die Untersuchung auf das Vorliegen der BRAF-Variante V595E ist ein hochspezifisches Verfahren, mit dem sich in histologisch und zytologisch fraglichen Fällen die Verdachtsdiagnose eines PCa absichern lässt. Durch die BRAF-Mutation verursachte PCa zeigen histologisch stärker ausgeprägte Malignitätskriterien als nicht durch diese Mutation bedingte. Die klinische, therapeutische und prognostische Relevanz dieser Befunde bedarf weiterer Studien.
Blutgasanalyse beim Kaninchen während einer vollständig antagonisierbaren Anästhesie unter besonderer Berücksichtigung des Sauerstoffmanagements
Authors: Brezina Tina , Fehr Michael , Thöle Milena
Published: October 2019

Ziel Das Ziel dieser Studie war, die Auswirkung verschiedener Formen der Sauerstoffdarreichung auf die Werte der arteriellen Blutgasanalyse während einer Injektionsanästhesie darzustellen.

Material und Methoden Insgesamt 29 Kaninchen mit Zahnerkrankung (coronaler Überlänge) wurden vor, während und nach einer Okklusionskorrektur beprobt. Die Applikation von Sauerstoff erfolgte entweder per Flow-by-Methode oder über eine Sauerstoffbrille; in der Kontrollgruppe atmeten die Tiere Raumluft.

Ergebnisse Alle Patienten, die Sauerstoff erhalten hatten, entwickelten eine respiratorische Azidose, die sich über den Zeitraum der Anästhesie verstärkte. Zudem zeigten sie intraoperativ reduzierte Atemfrequenzen, aber dennoch erhöhte Sauerstoffparameter (Hyperoxämie) in der arteriellen Blutgasanalyse. Zwischen den beiden Methoden der Sauerstoffzufuhr ergab sich kein signifikanter Unterschied. In der Kontrollgruppe blieb der pH-Wert stabil, die Sauerstoffparameter sanken jedoch auf unter 80 mmHg (Hypoxämie).

Schlussfolgerung Obwohl es klinisch zu keiner sichtbaren Auswirkung der Hypoxämie oder Hyperoxämie kam, ist eine moderate Sauerstoffzufuhr während einer Injektionsanästhesie aufgrund der sich entwickelnden Hypoxämie empfehlenswert. Eine Balance zwischen Sauerstoffangebot und Überangebot sollte zukünftig ermittelt werden, um Schädigungen zu vermeiden.
Prophylactic Effect of Opuntia ficus indica Fruit Peel Extract against Irradiation-Induced Colon Injury in Rats
Authors: Elsawi Salma A. , Radwan Rasha R. , Elbatanony Marwa M. , El-Feky Amal M. , Sherif N. H.
Published: October 2019

Opuntia ficus-indica extract has been used in traditional folk medicine for several purposes and exhibits anti-inflammatory properties. This study was directed to explore the prophylactic effect of O. ficus-indica fruit peel extract against irradiation-induced colitis in rats. GC/MS analysis of the petroleum ether extract led to recognition of 33 compounds in the unsaponifiable fraction and 15 fatty acid methyl esters in the saponifiable part. Thirteen terpenes and sterols were isolated and identified from which ten compounds were not isolated from any part of this species before. Data showed that irradiation induced colon injury as manifested by elevated contents of malondialdehyde, nitric oxide, myeloperoxidase, intercellular adhesion molecule-1, cyclooxygenase-2, tumor necrosis factor alpha, and nuclear factor kappa B, while it reduced superoxide dismutase activity and interleukin 10 content in colonic tissues, which was confirmed by histopathological examination. Pretreatment with O. ficus-indica extract attenuated the alteration in the measured parameters. It could be concluded that O. ficus-indica fruit peel extract can be regarded as a potential agent in limiting colonic complications due to irradiation, possibly by its antioxidant and anti-inflammatory properties.
The Effect of Oral Health Knowledge, Attitude, and Practice on Periodontal Status among Dental Students
Authors: Ahmad Fatemah A. , Alotaibi Mazen K. , Baseer Mohammad Abdul , Shafshak Sanaa M.
Published: October 2019

Objectives The primary aim of the current study is to relate oral health knowledge, attitude, and oral hygiene practice with the periodontal condition of both undergraduate and postgraduate dental students.

Materials and Methods Data were collected through a combination of self-reported questionnaire and clinical examination. The estimated sample size was 246. Probing depths and clinical attachment loss were measured in interproximal sites, whereas the gingival index was calculated based on Ramfjord teeth. The Centers for Disease Control and the American Academy of Periodontology classification was used for periodontal diagnosis. The subjects were divided into three groups. Group 1 was composed of undergraduate, preclinical dental students, group 2 consisted of undergraduate clinical-year dental students, whereas group 3 included postgraduate residents.

Results A total of 296 dental students participated in this study. Significant differences were found among the groups in their oral health knowledge, attitude, and practice scores. Gingival disease was detected among most of the participants (99.2–100%) with significant differences between different educational levels (group 1 = 1.13, group 2 = 1.16, group 3 = 0.96, p-value = 0.001). Sixty percent of dental students were diagnosed with periodontal disease regardless of its severity. A positive correlation was established between oral health knowledge and attitude and oral hygiene practice. In addition, gingival inflammation severity and the severity of periodontal disease showed a positive correlation.

Conclusions This study highlighted the need to improve the oral health knowledge, attitude, and practice of dental students. Gingival and periodontal inflammation was highly prevalent among participants.
Cephalometric Evaluation of Vertical Dimension of Occlusion in Varying Malocclusions
Authors: Aggarwal Isha , Mallik Anindita , Mittal Sanjay , Bhullar Mandeep , Singla Divya , Goyal Merry
Published: October 2019

Introduction The aim of modern cephalometrics is to evaluate the relationship of skeletal and dental functional units of the face and to implement treatment to establish the position of the units horizontally and vertically. Establishing a correct occlusal vertical dimension is considered one of the most important aspects of facial esthetics for patients in need of orthodontic treatment.

Aim The aim of this study is to evaluate the vertical dimension of occlusion in varying dental malocclusions in Solan population.

Materials and Methods The sample consisted of pretreatment lateral cephalograms of 100 patients (50 Class I and 50 Class II div 1), aged 15 to 30 years; six angular and one linear parameters were measured to determine the vertical dimension of occlusion.

Results All the parameters (Frankfort-mandibular plane angle [FMA], Occl/Frankfort horizontal plane [FHA], angle of Y-axis, Occl/SN, GoGn/SN, and ANS-Me) were found to be decreased in Class I than in Class II div 1 malocclusion except (ANS-Xi-Pm). All the parameters were found to be statistically significant (p < 0.05) when compared between groups. When cephalometric norms of the present study were compared with Moroccan population, all parameters (ANS-Xi-Ptm, FMA, Occl/FH, Occl/SN, GoGn/SN, and ANS-Me) were found to be decreased in Solan population except angle of Y-axis. All the parameters were clinically significant (p < 0.05) except ANS-Xi-Pm and FMA that were found to be clinically nonsignificant (p > 0.05).

Conclusion Solan population has distinct cephalometric characteristics, which should be used as the reference in future orthodontic treatments.
Cholemic Nephropathy Reloaded
Authors: Fickert Peter , Rosenkranz Alexander R.
Published: October 2019

Acute kidney injury (AKI) is a dreaded complication in patients with liver disease and jaundice, since it is associated with significant morbidity and mortality. Cholemic nephropathy (CN) is thought to represent a widely underestimated important cause of AKI in advanced liver diseases with jaundice. The umbrella term CN describes impaired renal function along with histomorphological changes consisting of intratubular cast formation and tubular epithelial cell injury directed primarily toward distal nephron segments. In cholestasis, biliary constituents may be excreted via the kidney and bilirubin or bile acids may trigger tubular injury and cast formation, but as we begin to understand the underlying pathophysiologic mechanisms, we become increasingly aware of the urgent need for clearly defined diagnostic criteria. In the following, we aim to summarize current knowledge of clinical and morphological characteristics of CN, discuss potential pathomechanisms, and raise key questions to stimulate evolution of a research strategy for CN.
Quasi doubly stochastic operator on l1 and Nielsen’s theorem
Authors: Manjegani Seyed Mahmoud , Moein Shirin
Published: October 2019

In this paper, we introduce the quasidoubly stochastic operator, which is between doubly stochastic operators and column stochastic operators, so as to apply to characterized operator S on l1 such that Sf is majorized by f for every f ∈ l1. We present some classes of majorization preservers on l1 under quasi doubly stochastic operators. Moreover, as an application of our result in quantum physics, the convertibility of pure states of a composite system by local operations and classical communication has been considered.
Fabrication and characterization of graphene-based paper for heat spreader applications
Authors: Muhsan Ali A. , Lafdi Khalid
Published: October 2019

In this work, in-plane thermal conductivity measurement was carried out on graphene-based papers. Graphene-based papers were fabricated using various processing techniques such as chemical vapor deposition (CVD), hot pressing of graphene slurry, and evaporation induced self-assembly. The prepared materials were characterized using scanning electron microscopy, Raman spectroscopy, and X-ray diffraction. In-plane thermal conductivity measurement was performed via a steady state thin film thermal conductivity apparatus. The in-plane thermal conductivity measurements show that the CVD based sample has the highest thermal conductivity. COMSOL Multiphysics was used to simulate the in-plane thermal conductivity of graphene-based papers.
Dissipative particle dynamics for directed self-assembly of block copolymers
Authors: Huang Hejin , Alexander-Katz Alfredo
Published: October 2019

The dissipative particle dynamics (DPD) simulation method has been shown to be a promising tool to study self-assembly of soft matter systems. In particular, it has been used to study block copolymer (BCP) self-assembly. However, previous parameterizations of this model are not able to capture most of the rich phase behaviors of BCPs in thin films nor in directed self-assembly (chemoepitaxy or graphoepitaxy). Here, we extend the applicability of the DPD method for BCPs to make it applicable to thin films and directed self-assembly. Our new reparameterization not only is able to reproduce the bulk phase behavior but also manages to predict thin film structures obtained experimentally from chemoepitaxy or graphoepitaxy. A number of different complex structures, such as bilayer nanomeshes, 90° bend structures, circular cylinders/lamellae and Frank-Kasper phases directed by trenches, and post arrays or chemically patterned substrates, have all been reproduced in this work. This reparameterized DPD model should serves as a powerful tool to predict BCP self-assembly, especially in some complex systems where it is difficult to implement self-consistent field theory.
H
3
+
as a five-body problem described with explicitly correlated Gaussian basis sets
Authors: Muolo Andrea , Mátyus Edit , Reiher Markus
Published: October 2019

Various explicitly correlated Gaussian (ECG) basis sets are considered for the solution of the molecular Schrödinger equation with particular attention to the simplest polyatomic system, H3+. Shortcomings and advantages are discussed for plain ECGs, ECGs with the global vector representation, floating ECGs and their numerical projection, and ECGs with complex parameters. The discussion is accompanied with particle density plots to visualize the observations. In order to be able to use large complex ECG basis sets in molecular calculations, a numerically stable algorithm is developed, the efficiency of which is demonstrated for the lowest rotationally and vibrationally excited states of H2 and H3+.
Effects of paramagnetic interactions by the partial replacement of Zn2+ ions with Cu2+ ions in lead-free zinc-based perovskite (MA)2ZnCl4 crystal by MAS NMR
Authors: Lim Ae Ran
Published: October 2019

The growths, structures, phase transition temperatures, and molecular dynamics of mixed (MA)2Zn1-xCuxCl4 (x=0, 0.3, 0.5, 0.7, and 1) crystals were investigated to understand the effect of the random presence of paramagnetic Cu2+. In addition, the spin-lattice relaxation time T1ρ in the rotating frame by the magic angle spinning nuclear magnetic resonance (MAS NMR) method was obtained for 1H and 13C nuclei to understand the molecular dynamics for varying amounts of Cu2+ ions. The structure and phase transition temperature for the case where x=0.3 was similar to those for x=0, whereas those of x=0.5 and 0.7 were similar to those for x=1. Although the crystal structures and phase transition temperatures were similar for x (=0 and 0.3), and x (=0.5, 0.7, and 1), the molecular motions of 1H and 13C for x=0.3 differed from those for x=0, 0.5, 0.7, and 1. We compared the activation energies Ea by the molecular motions for 1H and 13C, based on the T1ρ. The Cu2+ presence for x=0.3 in the mixed structure indicates any differences in the Ea for 1H and 13C, and the replacement of Zn2+ ions by Cu2+ ions for x=0.3 was strongly affected by the molecular motions.
High power electron beam interaction with an aluminum target: Measurements and simulations
Authors: Gardelle J. , Cassany B. , Szalek N. , Galtié A. , Bicrel B. , Hébert D. , Bertron I. , Pepitone K.
Published: October 2019

The study of the dynamic response of materials induced by electron beams requires precise knowledge of the beam when it interacts with the material. In this framework, the CESAR generator is used at CESTA. CESAR drives a field emission diode that delivers a single-shot intense electron pulse (≈1 MV, 300 kA, and 100 ns). The electron beam propagates into a gas-filled chamber where it is focused by a magnetic field onto an aluminum target. The analysis of the beam characteristics at the target position allows us to estimate the initial conditions required for precise hydrodynamic simulations. In this paper, we present the measurements of the electron beam characteristics. We paid particular attention to voltage, current, spatial homogeneity, dose rate, and incidence angles of electrons onto the target. Shocks induced in thin discs of aluminum are analyzed by using photon Doppler velocimetry, and the experimental data are compared with the predictions of simulations. Beam energy deposition is computed by using the 3D code Diane, and the hydrodynamic evolution of the target is performed with the code 2D/3D Hesione.
On the stability of a liquid layer bordering plasma
Authors: Nemchinsky Valerian
Published: October 2019

The surface of a liquid wall (cathode) in contact with plasma is subjected to the electric field and to the bombardment of plasma particles, mostly ions. The stability of electrocapillary waves at the wall surface is considered. In the first part of the paper, the motion of ions inside the sheath and its influence on the electric field distribution are considered in a self-consistent way. The stress exerted on the liquid surface by ions and the electric field is found. This stress is used to describe the liquid motion in the second (hydrodynamic) part of the paper. It allows us to obtain the dispersion relation of the electrocapillary waves and to find the most dangerous wavenumbers and corresponding instability increments. It is shown that disturbances with wavenumbers less than some critical value κ0 = kλ (λ is the Debye length) do not grow. Shorter disturbances grow if E, the electric field, at the wall exceeds a specific Ecrit number. Expressions for κ0 and Ecrit are obtained. The increment of instability for κ > κ0 and E > Ecrit is calculated. It is shown that the instability takes place within an interval of wavenumbers. The higher the electric field, the wider this interval and the higher the increment of the most dangerous instability. Calculations were performed for the liquid wall at floating potential bordering hydrogen and deuterium plasmas. It is shown that the instability takes place in a wider range of wavelengths and has a higher increment in the case of deuterium plasma than in the case of hydrogen plasma.
Full-dimensional three-state potential energy surfaces and state couplings for photodissociation of thiophenol
Authors: Zhang Linyao , Truhlar Donald G. , Sun Shaozeng
Published: October 2019

An analytic full-dimensional diabatic potential energy matrix (DPEM) for the lowest three singlet states of thiophenol (C6H5SH) at geometries accessible during photodissociation is constructed using the anchor points reactive potential (APRP) scheme. The data set used for modeling is obtained from electronic structure calculations including dynamic correlation via excitations into the virtual space of a three-state multiconfiguration self-consistent field calculation. The resulting DPEM is a function of all the internal coordinates of thiophenol. The DPEM as a function of the S−H bond stretch and C−C−S−H torsion and the diabatic couplings along two in-plane bend modes and nine out-of-plane distortion modes are computed using extended multiconfigurational quasidegenerate perturbation theory followed by the fourfold way determination of diabatic molecular orbitals and model space diabatization by configurational uniformity, and this dependence of the DPEM is represented by general functional forms. Potentials along 31 tertiary internal degrees of freedom are modeled with system-dependent, primary-coordinate-dependent nonreactive molecular mechanics-type force fields that are parameterized by Cartesian Hessians calculated by generalized Kohn-Sham density functional theory. Adiabatic potential energy surfaces (PESs) and nonadiabatic couplings are obtained by a transformation of the DPEM. The topography of the APRP PESs is characterized by vertical excitation energies, equilibrium geometries, vibrational frequencies, and conical intersections, and we find good agreement with available reference data. This analytic DPEM is suitable for full-dimensional electronically nonadiabatic molecular dynamics calculations of the photodissociation of thiophenol with analytic gradients in either the adiabatic or diabatic representation.
A pre-injector upgrade for ISIS, including a medium energy beam transport line and an RF-driven H− ion source
Authors: Lawrie S. R. , Abel R. E. , Cahill C. A. , Faircloth D. C. , Macgregor J. H. , Patel S. , de M. Sarmento T. C. , Speed J. , Tarvainen O. A. , Whitehead M. O. , Wood T. , Zacek D.
Published: October 2019

The ISIS spallation neutron and muon facility is undergoing an upgrade to the negative hydrogen (H−) linac preinjector with the addition of a medium-energy beam transport (MEBT) line. A fast electrostatic sweep chopper is included in the MEBT and will notch the linac bunch train at the synchrotron frequency. The MEBT and chopper will increase the beam transport efficiency significantly, reducing the output H− current requirements from the ion source. As such, a long-lifetime, noncesiated, RF-driven, external-antenna H− ion source based on the successful CERN Linac4 and SNS designs is constructed, which will improve facility uptime and reliability. This paper will highlight the latest developments on the MEBT before focusing on the RF ion source. The RF ion source must deliver 35 mA of H− beam current in pulses 400 μs long at a 50 Hz repetition rate, with transverse normalized 4 rms emittances less than 1.2 π mm mrad. The beam current and emittance are within the reach of a noncesiated H− source, whereas operating at relatively high duty cycles presents challenges in terms of thermal management, which this paper will address.
Understanding instability at the surface between liquid and plasma
Authors: Patrick Chris
Published: October 2019

Studying the instability of a liquid layer bordering plasma shows the importance of shear stress and yields the dispersion relation for capillary waves.
Effects of endogenous ascorbic acid on the distribution of photosynthetic electron flow in rice leaves
Authors: Zhang Qilei , Cai Minling , Lu Lina , Gao Hui , Peng Changlian
Published: October 2019

Ascorbic acid (Asc) is one of the major antioxidants in plants. l-Galactono-1,4-lactone dehydrogenase (GLDH) is an enzyme that catalyses the last step of Asc biosynthesis in higher plants. In this study the effects of endogenous Asc on the distribution of photosynthetic electron flow were investigated in wild-type (ZH-11) rice (Oryza sativa L.) and in GLDH-overexpressing (GO-2) and GLDH-suppressed (GI-2) transgenic rice. The ratio of photosynthetic electron flow distributed to Rubisco-dependent carboxylation was highest in GO-2, whereas other electron flows in addition to carbon fixation were highest in GI-2 after flowering. Further examination showed that the photosynthetic electron flow, GLDH content and reactive oxygen species-scavenging ability were highest in GO-2 and lowest in GI-2. Therefore, the senescence of leaves was faster in GI-2 but slower in GO-2 compared with ZH-11. In addition, leaves with higher Asc content had more Rubisco content and a superior photosynthetic rate, which increased rice yield. These results suggest that increasing the endogenous Asc content of rice delays senescence, maintains a higher photosynthetic rate and results in more photosynthetic electron flow distributed to Rubisco-dependent carboxylation, ultimately leading to increased rice yield.
Teaching in linguistically and culturally diverse secondary schools
Authors: Gleeson Margaret , Davison Chris
Published: October 2019

Thirty years ago Australian researchers led the development of language and content integration in schools, advocating systematic teaching of language across the curriculum to meet the needs of English as an additional language (EAL) students. However, despite significant improvements in initial teacher education, targeted professional development and language-specific curriculum and assessment, this paper suggests that secondary teachers have gained only a superficial understanding of the language knowledge necessary to teach EAL students. Drawing on questionnaires, interviews, and observations, this case study of two secondary schools in Sydney reveals the majority of teachers report their perspectives and experiences of good teaching have equipped them with a repertoire of sufficient strategies to meet EAL needs, and they see little difference between teaching EAL and learners with low levels of literacy. This paper concludes a renewed focus on integrating language and content teaching and partnership models of professional learning and evaluation are needed.
Do we X, Should/Shall we X, Let’s X
Authors: Sokol Robin
Published: October 2019

This article studies the formats Do we X, Should/Shall we X, and Let’s X in
order to deepen our understanding of face-to-face collaborative interactions at the computer. We use 6 hours of data of university
students collaborating in British and American English, and our methodology is Conversation Analysis. We demonstrate that the
participants display and orient to the immediacy/remoteness of the task, as well as their entitlement to carry out the proposed
task, when they put forward a proposed action. To do so, they use specific formats, specific verbs, and display specific tasks
depending on their needs, emerging from the unfolding of the collaboration. We argue that collaboration is not only a matter of
organising the accomplishment of a set of tasks, but also of displaying what kind of task is being proposed, and to what extent
the speaker is entitled to the proposed task.
The imagined Africa of the West: a critical perspective on Western imaginations of Africa
Authors: Larsen Rune , Jensen Stig
Published: October 2019

This debate piece discusses how exceptionalised images of Africa are reproduced in contemporary Western discourse and imagination, and argues that these exceptionalised depictions of Africa enable Western consciousness to escape a confrontation with its own dysfunctionalities, hereby projecting all the excremental features characterising human existence on to its African Other. This is interpreted as a way for Western subjects to alter themselves into a position of idealised and imagined advanced civilisation – thus legitimising contemporary acts of neo-colonial exploitation in Africa.
“Despite being an athlete, I am also a human‐being”: Male elite gymnasts’ reflections on food and body image
Authors: Pinto Ana Jéssica , Dolan Eimear , Baldissera Giovana , Gonçalves Lívia de Souza , Jardim Felipe Gregório de Araújo , Mazzolani Bruna Caruso , Smaira Fabiana Infante , Sato Priscila de Morais , Scagliusi Fernanda Baeza , Gualano Bruno
Published: October 2019

Our aim was to investigate the prevalence of symptoms related to eating disorders, disordered eating and body image perception, and attitudes toward eating in a group of elite male artistic gymnastics. Seventeen athletes took part in this quali‐quantitative, cross‐sectional study. Presence of eating disorders symptoms, and body image perception and satisfaction were assessed using validated questionnaires. Focus groups were held to discuss their attitudes toward eating and body image perception in more detail. Little to no evidence of symptoms consistent with eating disorders was observed, and this was supported by the qualitative data. However, some concerning practices and attitudes were described. Negative emotional eating cycles appeared prevalent (e.g. feelings of anger, stress and anxiety creating a desire to eat “junk foods”, followed by guilt and regret). Body image perception and attitudes toward body weight's influence on performance varied widely. Some athletes expressed a desire to lose weight and believed that this would positively impact their performance, while others believed weight to be irrelevant and focused on feeling strong and vital. Athletes believed their female counterparts experienced far greater pressure to maintain low body weight and described some very concerning practices. We conclude that eating disorders and disordered eating did not appear to be prevalent among these elite male artistic gymnastics. However, some concerning attitudes and practices were observed and should be addressed with nutritional support programmes encompassing psychological and behavioural aspects of eating. These programmes should be extended to support staff and significant others, in addition to athletes.
Model Predictions of Charged-Particle Azimuthal Distributions and Forward-Backward Correlations in pp Interactions at

s=900

GeV*
Authors: Khan R. , Ajaz M. , Ali Y. , Younis H. , Khan G. , Wazir Z. , Zaman A. , Khan A.
Published: October 2019

We report inelastic interactions of protons at the center of mass energy

s

=
900

GeV, by using different event generators to study the forward-backward (FB) correlation in summed transverse momentum and multiplicity of produced charged particles. The transverse momentum, pT
≥ 100 MeV, and pseudorapidity, |η| < 2.5, have been employed for both the correlations. The simulation results are compared with the ATLAS experimental data, obtained with the same values of |η| and pT
at

s

=
900

GeV. We also measure the jet and jet-like structure as a function of azimuthal distributions in the events relative to the highest transverse momentum particle. Three overlapping regions of pseudorapidity, |η| < 1.0, |η| < 2.0, and |η| < 2.5 are used with transverse momentum, pT
> 500 MeV. For FB correlations, EPOS, and Sybill2.3c results are in a good agreement with the data as compared to the other models. Similarly, for the azimuthal distribution, EPOS-LHC, DPMJETIII, and Sibyll2.3c show good agreement with the data for full η region. In general, EPOS provides a better description of the data for both the quantities studied in this paper.
Orthonormality of Volkov Solutions and the Sufficient Condition*
Authors: Wang Hao , Zhong Ming , Gan Long-Fei
Published: October 2019

We present a simple demonstration on the orthonormality of Volkov solutions with emphasizing on the sufficient condition to the orthonormality. Properly aligning the external electromagnetic wave along the third-axis, the Volkov solutions are eigenfunctions of the hermitian momentum

p
^

1

,

p
^

2

and the light-cone hamiltonian operators with real eigenvalues, which can lead to a verification of the orthonormality in the context of quantum mechanics when the x
3-integration of the external potential is not singularity as severe as δ(0). The hermiticity of the fermion field four-momentum operators validates the application of the demonstration to the intense field quantum electrodynamic. The proof based on a direct calculation to the inner products of the solutions is recapitulated as well in a general manner without dependence on explicit representation of the Dirac matrices and spinors, which can be conducive to understand the sufficient condition and to the study of the polarized electron production where a convenient representation is selected elaborately to project out the spin-polarization.
Geodesic Structure of a Non-linear Magnetic Charged Black Hole Surrounded by Quintessence*
Authors: Shi Li-Li , Hu Jian-Ping , Zhang Yu , Ma Chen , Duan Peng-Fei
Published: October 2019

This paper aims to investigate the geodesic motion in the spacetime of a non-linear magnetic charged black hole surrounded by quintessence. By varying the Lagrangian corresponding to the metric, the orbital motion equation has been obtained. The effects of the magnetic charge Q, positive normalization factor C, angular momentum b, and energy E on time-like and null geodesic motion are discussed from three aspects: orbital stability, orbital types, and circular orbits. By comparing the effects of the above parameters C, b on the effective potential, it is found that quintessence has an impact on the types and stability of orbits. In addition, for time-like orbital motion, when 3.443113 ≤ b ≤ 6.392 578 (for fixed C = 0.0002, M = 1, Q = 0.7), there are bound orbits, and within this range, the stable circular orbits exist, and the radii of the innermost and outermost stable circular orbit are r = 5.912 654 and r = 56.745 933, respectively. For null orbital motion, the orbital types have only unstable circular orbit which occur at r = 2.951 072 (

E
2

=

E
2
2

=
0.4

), absorb orbits and escape orbits, but no stable circular orbits, and bound orbits.
A Gravitational Wave Background from Primordial Black Hole Lattices in Matter Dominated Era*
Authors: Wang Ke
Published: October 2019

We use the wide-used Einstein Toolkit to solve the Einstein constraints and then simulate the expansion of primordial black hole lattices (PBHLs) with different value of f
PBH
and m
PBH. We find that f
PBH
plays an important role during the evolution of PBHLs. Since the motion of primordial black holes (PBHs) caused by the expansion of PBHLs occurs at speeds close to that of light, we expect the emission of gravitational waves (GWs) during the expansion of PBHLs. We use both analytical estimates and numerical simulations to cross check the production of GWs in expanding PBHLs.
Background Dynamics of Pre-inflationary Scenario in Brans-Dicke Loop Quantum Cosmology*
Authors: Sharma Manabendra , Zhu Tao , Wang Anzhong
Published: October 2019

Recently the background independent nonperturbative quantization has been extended to various theories of gravity and the corresponding quantum effective cosmology has been derived, which provides us with necessary avenue to explore the pre-inflationary dynamics. Brans-Dicke (BD) loop quantum cosmology (LQC) is one of such theories whose effective background dynamics is considered in this article. Starting with a quantum bounce, we explore the pre-inflationary dynamics of a universe sourced by a scalar field with the Starobinsky potential in BD-LQC. Our study is based on the idea that though Einstein’s and Jordan’s frames are classically equivalent up to a conformal transformation in BD theory, this is no longer true after quantization. Taking the Jordan frame as the physical one we explore in detail the bouncing scenario which is followed by a phase of a slow roll inflation. The three phases of the evolution of the universe, namely, bouncing, transition from quantum bounce to classical universe, and the slow roll inflation, are noted for an initially kinetic energy dominated bounce. In addition, to be consistent with observations, we also identify the allowed phase space of initial conditions that would produce at least 60 e-folds of expansion during the slow roll inflation.
Superstatistics of Modified Rosen-Morse Potential with Dirac Delta and Uniform Distributions
Authors: Okorie U. S. , Ikot A. N. , Rampho G. J. , Sever R.
Published: October 2019

We discuss the thermodynamic properties of a modified Rosen-Morse potential using the q-deformed superstatistics approaches. We obtain the partition function with the help of the generalized Boltzmann factor from the modified Dirac delta distribution and uniform distribution. Other thermodynamic function is obtained for the superstatistics of the two distributions considered. We also discuss our results graphically and obtain the ordinary statistical quantities when the deformation parameter tends to zero.
Mapping Between Charge-Dyon and Position-Dependent Mass Systems*
Authors: de Jesus Anderson L. , Schmidt Alexandre G. M.
Published: October 2019

The primary purpose of this work is to reproduce the scenario composed of a charge-dyon system utilizing position-dependent effective mass (PDM) background in the non-relativistic and in the relativistic regimes. In the non-relativistic case we substitute the exact charge-dyon eigenfunction into PDM Schrödinger equation, in the Zhu-Kroemer parametrization, and then solve it for the mass distribution considering M = M(r). Analogously, in the relativistic case we study the Klein-Gordon equation for a position-dependent mass, and in this case, we are able to analytically solve the equation for M = M(r,θ).
Time-of-flight (TOF) implementation for PET reconstruction in practice
Authors: Filipović Marina , Comtat Claude , Stute Simon
Published: October 2019

The time-of-flight (TOF) feature of PET scanners has been used for a long time in PET reconstruction, but many implementational aspects are still incomplete or ambiguous in the literature. Here we formalize and present theoretical and practical implementation details for the reconstruction of clinical TOF histogram and list-mode data using ML-EM. Relevant aspects include the computation of the TOF component of the system matrix, the processing of TOF bins, the use of estimations of random and scattered coincidences, and differences between histogram and list-mode ML-EM TOF reconstruction. Several approaches and approximations have been implemented in the CASToR platform and compared for OSEM reconstructions of patient data from the GE Signa PET/MR scanner. Differences between implementations are not larger than the typical bias in clinical data reconstruction. The largest difference and contrast loss occur when the processing of histogram TOF bins is simplified, and list-mode reconstruction is most sensitive to the truncation of the Gaussian TOF probability distribution.
Gouy and spatial-curvature-induced phase shifts of light in two-dimensional curved space
Authors: Xu Chenni , Wang Li-Gang
Published: October 2019

Gouy phase is the axial phase anomaly of converging light waves discovered over one century ago, and is so far widely studied in various systems. In this work, we have theoretically calculated Gouy phase of light beams in both paraxial and nonparaxial regime on two-dimensional curved surface by generalizing angular spectrum method. We find that curvature of surface will also introduce an extra phase shift, which is named as spatial curvature-induced (SCI) phase. The behaviors of both phase shifts are illustrated on two typical surfaces of revolution, circular truncated cone and spherical surface. Gouy phase evolves slower on surface with greater spatial curvature on circular truncated cone, which is however opposite on spherical surface, while SCI phase evolves faster with curvature on both surfaces. On circular truncated cone, both phase shifts approach to a limit value along propagation, which does not happen on spherical surface due to the existence of singularity on the pole. An interpretation is presented to explain this peculiar phenomenon. Finally we also provide the analytical expression of paraxial Gaussian beam on general SORs. By comparing the result with the exact method we find the analytical expression is valid under the approximation that beam waist and scale of surface are beyond order of wavelength. We expect this work will enhance the comprehension about the behavior of electromagnetic wave in curved space, and further contribute to the study of general relativity phenomena in laboratory.
All-acoustic signal modulation and logic operation via defect induced cavity effects in phononic crystal coupled-resonator acoustic waveguides
Authors: Reyes Delfino , Walker Ezekiel , Zubov Yurii , Heo Hyeonu , Krokhin Arkadii , Neogi Arup
Published: October 2019

A coupled resonant acoustic waveguide (CRAW) in a phononic crystal (PnC) was engineered to manipulate the propagation of ultrasonic waves within a conventional phononic bandgap for wavelength division multiplexing. The PnC device included two, forked, distinct CRAW waveguide channels that exhibited strong frequency and mode selectivity. Each branch was composed of cavities of differing volumes, with each giving rise to deep and shallow ‘impurity’ states. These states were utilized to select frequency windows where transmission along the channels was suppressed distinctly for each channel. Though completely a linear system, the mode sensitivity of each CRAW waveguide channel produced apparent nonlinear power dependence along each branch. Nonlinearity in the system arises from the combination of the mode sensitivity of each CRAW channel and small variations in the shape of the incident wavefront as a function of input power. The all-acoustic effect was then leveraged to realize an ultrasonic, spatial signal modulator, and logic element operating at 398 and 450 kHz using input power.
Polarization-based branch selection of bound states in the continuum in dielectric waveguide modes anti-crossed by a metal grating
Authors: Kikkawa R , Nishida M , Kadoya Y
Published: October 2019

We investigate bound states in the continuum (BICs) in a planar dielectric waveguide structure consisting of a gold grating on a dielectric layer with a back layer of metal. In this structure, Friedrich–Wintgen (FW) BICs caused by the destructive interference between the radiations from two waveguide modes appear near the anti-crossing point of the dispersion curves. In this study, it is revealed that the branch at which the BIC appears changes according to the polarization of the modes. Based on a temporal coupled mode theory, it is shown that the BIC branch is determined by the sign of the product of the coupling coefficients between the two waveguide modes and external radiation, which is consistent with FW theory. The signs of the coupling coefficients are estimated by the waveguide-mode decomposition of the numerically obtained electric fields and are confirmed to vary depending on the polarization.
A PCA approach to stellar abundances I. testing of the method validity
Authors: He Wei , Zhao Gang
Published: October 2019

The derivation of element abundances of stars is a key step in detailed spectroscopic analysis. A spectroscopic method may suffer from errors associated with model simplifications. We have developed a new method of deriving the various element abundances of stars based on the calibration established from a group of standard stars. We perform principal component analysis (PCA) on a homogeneous library of stellar spectra, and then use machine learning to calibrate the relationship between principal components and element abundances. By testing with spectral libraries S4N and MILES, we find that our procedure provides good consistency when spectra from a homogeneous set of observations are used, and it could be expanded to stars with quite a wide range of stellar parameters, with both dwarfs and giants. Moreover, we discuss the four key factors that have a significant impact on the results of derived element abundances, including the resolution of the spectra, wavelength range, the signal-to-noise ratio (S/N) of spectra and the number of principal components adopted.
Simultaneous optical g, r, i monitoring and IDV periodic analysis for quasar 3C 454.3
Authors: Fan Jun-Hui , Yuan Yu-Hai , Wu Hong , Wang Feng , Tao Jun , Gu Min-Feng
Published: October 2019

With the 1.26 m National Astronomical Observatory-Guangzhou University Infrared/Optical Telescope (NAGIOT) at Xinglong Station of National Astronomical Observatories, Chinese Academy of Sciences, we obtained 419 groups of simultaneous observations at g, r and i bands, for the first time, targeting quasar 3C 454.3 during 15 nights from 2016 October 23 to 2016 December 15. Based on our observations, we investigate the optical variabilities, the relation between brightness and color index, and the periodicity variability. The presented analyses demonstrate that: 1. The maximum variations at the g, r and i bands are Δ m

g|max = 1.015 ± 0.042 mag, Δ m

r|max = 1.188 ± 0.050 mag and Δ m

i|max = 1.305 ± 0.057 mag respectively. 2. During our 15 night monitoring program, intra-day variability was detected on one night (Nov. 2). Also, the brightness increased by A = 15.86% over 50.8 min, then decreased by A = 22.42% over 40.1 min. After a small bright state, its brightness increased again by 18.1% over 55 min at the g band. Similar phenomena happened at r and i bands. The intra-day variabilities at the three bands on 2016 November 2 indicate a period of 105 min, which implies a black hole mass of M
BH = (0.3 ∼ 1.85) × 109
M
⊙. 3. There is an anti-correlation between color index and magnitude, suggesting the source becomes redder when it brightens.
Low-mass and high-mass supermassive black holes in radio-loud AGNs are spun-up in different evolution paths
Authors: Wang Jing , Kong Min-Zhi , Liu Shun-Fang , Xu Da-Wei , Zhang Qiang , Wei Jian-Yan
Published: October 2019

How supermassive black holes (SMBHs) are spun-up is a key issue in modern astrophysics. As an extension to the study in Wang et al., here we address the issue by comparing the host galaxy properties of nearby (z < 0.05) radio-selected Seyfert 2 galaxies. With the two-dimensional bulge+disk decompositions for the SDSS r-band images, we identify a dichotomy in various host galaxy properties for radio-loud SMBHs. By assuming that radio emission from the jet reflects a high SMBH spin, which stems from the well-known Blandford-Znajek mechanism of jet production, high-mass SMBHs (i.e., M
BH > 107.9
M
⊙) have a preference for being spun-up in classical bulges, and low-mass SMBHs (i.e., M
BH = 106 − 107
M
⊙) in pseudo-bulges. This dichotomy suggests and confirms that high-mass and low-mass SMBHs are spun-up in different ways, i.e., a major “dry” merger and a secular evolution respectively.
Meta-analysis of electron cyclotron resonance absorption features detected in high-mass X-ray binaries
Authors: Christodoulou Dimitris M. , Laycock Silas G. T. , Kazanas Demosthenes
Published: October 2019

Using recent compilations of detailed X-ray observations and spectral models of exceptional quality, we record the electron cyclotron resonance absorption (ECRA) features that have been detected in 45 pulsating high-mass X-ray binaries (HMXBs) and ultraluminous X-ray (ULX) sources harboring neutron stars, although seven of these detections are still questionable and another 21 are single and/or not independently confirmed. From the comprehensive catalogs of Jaisawal & Naik and Staubert et al. and from several additional recent observations, we produce two lists of HMXB ECRA sources: a list of 17 sources in which multiple ECRA lines or single very low-energy lines are seen, in which we can reasonably assume that the lowest energy reveals the fundamental cyclotron level for each source; and a “contaminated” list of 38 sources including the 21 detections of single ECRA lines that may (not) be higher-level harmonics. Both lists confirm a previous result that we have obtained independently by modeling the propeller lines of Magellanic HMXB pulsars: the surface dipolar magnetic fields B
* of HMXB neutron stars are segregated around five distinct values with B
* = 0.28 ± 0.08, 0.55 ± 0.11, 1.3 ± 0.37, 3.0 ± 0.68 and 7.9 ± 3.1, in units of TG. However, an explanation of this phenomenon is currently lacking. We have found no correlation between these B
* values and the corresponding observed spin periods, spin period derivatives, orbital periods, maximum X-ray luminosities, neutron star masses or companion star masses.