bluuebunny/crossref_metadata_2025 huggingface dataset:
Bird’s eye view of molecular clouds in the Milky Way
Authors: Spilker Andri , Kainulainen Jouni , Orkisz Jan
Published: August 2021

Context. Describing how the properties of the interstellar medium are combined across various size scales is crucial for understanding star formation scaling laws and connecting Galactic and extragalactic data of molecular clouds.

Aims. We describe how the statistical structure of the clouds and its connection to star formation changes from sub-parsec to kiloparsec scales in a complete region within the Milky Way disk.

Methods. We built a census of molecular clouds within 2 kpc from the Sun using data from the literature. We examined the dust-based column density probability distributions (N-PDFs) of the clouds and their relation to star formation as traced by young stellar objects (YSOs). We then examined our survey region from the outside, within apertures of varying sizes, and describe how the N-PDFs and their relation to star formation changes with the size scale.

Results. We present a census of the molecular clouds within 2 kpc distance, including 72 clouds and YSO counts for 44 of them. The N-PDFs of the clouds are not well described by any single simple model; use of any single model may bias the interpretation of the N-PDFs. The top-heaviness of the N-PDFs correlates with star formation activity, and the correlation changes with Galactic environment (spiral- and inter-arm regions). We find that the density contrast of clouds may be more intimately linked to star formation than the dense gas mass fraction. The aperture-averaged N-PDFs vary with the size scale and are more top-heavy for larger apertures. The top-heaviness of the aperture N-PDFs correlates with star formation activity up to roughly 0.5 kpc, depending on the environment. Our results suggest that the relations between cloud structure and star formation are environment specific and best captured by relative quantities (e.g. the density contrast). Finally, we show that the density structures of individual clouds give rise to a kiloparsec-scale Kennicutt-Schmidt relation as a combination of sampling effects and blending of different galactic environments.
SSTRED: Data- and metadata-processing pipeline for CHROMIS and CRISP
Authors: Löfdahl Mats G. , Hillberg Tomas , de la Cruz Rodríguez Jaime , Vissers Gregal , Andriienko Oleksii , Scharmer Göran B. , Haugan Stein V. H. , Fredvik Terje
Published: August 2021

Context. Data from ground-based, high-resolution solar telescopes can only be used for science with calibrations and processing, which requires detailed knowledge about the instrumentation. Space-based solar telescopes provide science-ready data, which are easier to work with for researchers whose expertise is in the interpretation of data. Recently, data-processing pipelines for ground-based instruments have been constructed.

Aims. We aim to provide observers with a user-friendly data pipeline for data from the Swedish 1-meter Solar Telescope (SST) that delivers science-ready data together with the metadata needed for proper interpretation and archiving.

Methods. We briefly describe the CHROMospheric Imaging Spectrometer (CHROMIS) instrument, including its (pre)filters, as well as recent upgrades to the CRisp Imaging SpectroPolarimeter (CRISP) prefilters and polarization optics. We summarize the processing steps from raw data to science-ready data cubes in FITS files. We report calibrations and compensations for data imperfections in detail. Misalignment of Ca II data due to wavelength-dependent dispersion is identified, characterized, and compensated for. We describe intensity calibrations that remove or reduce the effects of filter transmission profiles as well as solar elevation changes. We present REDUX, a new version of the MOMFBD image restoration code, with multiple enhancements and new features. It uses projective transforms for the registration of multiple detectors. We describe how image restoration is used with CRISP and CHROMIS data. The science-ready output is delivered in FITS files, with metadata compliant with the SOLARNET recommendations. Data cube coordinates are specified within the World Coordinate System (WCS). Cavity errors are specified as distortions of the WCS wavelength coordinate with an extension of existing WCS notation. We establish notation for specifying the reference system for Stokes vectors with reference to WCS coordinate directions. The CRIsp SPectral EXplorer (CRISPEX) data-cube browser has been extended to accept SSTRED output and to take advantage of the SOLARNET metadata.

Results. SSTRED is a mature data-processing pipeline for imaging instruments, developed and used for the SST/CHROMIS imaging spectrometer and the SST/CRISP spectropolarimeter. SSTRED delivers well-characterized, science-ready, archival-quality FITS files with well-defined metadata. The SSTRED code, as well as REDUX and CRISPEX, is freely available through git repositories.
Connecting solar flare hard X-ray spectra to in situ electron spectra
Authors: Dresing N. , Warmuth A. , Effenberger F. , Klein K.-L. , Musset S. , Glesener L. , Brüdern M.
Published: August 2021

Aims. We aim to constrain the acceleration, injection, and transport processes of flare-accelerated energetic electrons by comparing their characteristics at the Sun with those injected into interplanetary space.

Methods. We have identified 17 energetic electron events well-observed with the SEPT instrument aboard STEREO which show a clear association with a hard X-ray (HXR) flare observed with the RHESSI spacecraft. We compare the spectral indices of the RHESSI HXR spectra with those of the interplanetary electrons. Because of the frequent double-power-law shape of the in situ electron spectra, we paid special attention to the choice of the spectral index used for comparison.

Results. The time difference between the electron onsets and the associated type III and microwave bursts suggests that the electron events are detected at 1 AU with apparent delays ranging from 9 to 41 min. While the parent solar activity is clearly impulsive, also showing a high correlation with extreme ultraviolet jets, most of the studied events occur in temporal coincidence with coronal mass ejections (CMEs). In spite of the observed onset delays and presence of CMEs in the low corona, we find a significant correlation of about 0.8 between the spectral indices of the HXR flare and the in situ electrons. The correlations increase if only events with significant anisotropy are considered. This suggests that transport effects can alter the injected spectra leading to a strongly reduced imprint of the flare acceleration.

Conclusions. We conclude that interplanetary transport effects must be taken into account when inferring the initial acceleration of solar energetic electron events. Although our results suggest a clear imprint of flare acceleration for the analyzed event sample, a secondary acceleration might be present which could account for the observed delays. However, the limited and variable pitch-angle coverage of SEPT could also be the reason for the observed delays.
Discovery of methanimine (CH2NH) megamasers toward compact obscured galaxy nuclei
Authors: Gorski M. D. , Aalto S. , Mangum J. , Momjian E. , Black J. H. , Falstad N. , Gullberg B. , König S. , Onishi K. , Sato M. , Stanley F.
Published: August 2021

We present the first search for the 5.29 GHz methanimine (CH2NH) 110 − 111 transition toward a sample of galaxy nuclei. We target seven galaxies that host compact obscured nuclei (CONs) with the Karl G. Jansky Very Large Array. These galaxies are characterized by Compton-thick cores. CH2NH emission is detected toward six CONs. The brightness temperatures measured toward Arp 220 indicate maser emission. Isotropic luminosities of the CH2NH transition, from all sources where it is detected, exceed 1 L⊙ and thus may be considered megamasers. We also detect formaldehyde (H2CO) emission toward three CONs. The isotropic CH2NH luminosities are weakly correlated with the infrared luminosity of the host galaxy and strongly correlated with OH megamaser luminosities from the same galaxies. Non-local thermodynamic equilibrium radiative transfer models suggest that the maser is pumped by the intense millimeter-to-submillimeter Our study suggests that CH2NH megamasers are linked to the nuclear processes within 100 pc of the Compton-thick nucleus within CONs.
Chemodynamics of metal-poor wide binaries in the Galactic halo: Association with the Sequoia event
Authors: Lim Dongwook , Koch-Hansen Andreas J. , Hansen Camilla Juul , Lépine Sebastien , Marshall Jennifer L. , Wilkinson Mark I. , Peñarrubia Jorge
Published: August 2021

Recently, an increasing number of wide binaries has been discovered. Their chemical and dynamical properties are studied through extensive surveys and pointed observations. However, the formation of these wide binaries is far from clear, although several scenarios have been suggested. In order to investigate the chemical compositions of these systems, we analysed high-resolution spectroscopy of three wide binary pairs belonging to the Galactic halo. In total, another three candidates from our original sample of 11 candidates observed at various resolutions with various instruments were refuted as co-moving pairs because their radial velocities are significantly different. Within our sample of wide binaries, we found homogeneity amongst the pair components in dynamical properties (proper motion and line-of-sight velocities) and also in chemical composition. Their metallicities are −1.16, −1.42, and −0.79 dex in [Fe/H] for each wide binary pair, which places these stars on the metal-poor side of wide binaries reported in the literature. In particular, the most metal-poor pair in our sample (WB2 ≡ HD 134439/HD 134440) shows a lower [α/Fe] abundance ratio than Milky Way field stars, which is a clear signature of an accreted object. We also confirmed that this wide binary shares remarkably similar orbital properties with stars and globular clusters associated with the Sequoia event. Thus, it appears that the WB2 pair was formed in a dwarf galaxy environment and subsequently dissolved into the Milky Way halo. Although the other two wide binaries appear to arise from a different formation mechanism, our results provide a novel opportunity for understanding the formation of wide binaries and the assembly process of the Milky Way.
Kompetenzen in der Notfallsanitäter*innenprüfung – eine Analyse
praktischer Prüfungsergebnisse
Authors: Buder Robert , Heller Florian , Dercks Sebastian , Winterstein Ivo , Trenkmann Lars
Published: August 2021

Einführung Die Implementierung der Notfallsanitäter*innenausbildung 2014
veränderte den Rettungsdienst nachhaltig. Es existieren keine wissenschaftlichen
Erkenntnisse zur curricularen Schwerpunktsetzung.

Methodik Es wurde eine retrospektive Datenanalyse praktischer
Prüfungsprotokolle von staatlichen Prüfungen, die von Rettungsassistent*innen
zwischen 2015–2018 abgelegt wurden, durchgeführt.

Ergebnisse Die praktischen Prüfungsergebnisse von 123 Teilnehmenden wurden
ausgewertet. Die traumatologischen Szenarien fielen mit einer Erfolgsrate von
77,2% am schlechtesten aus (internistisch 81,3%, Reanimation 83,7%, sonstige
82,9%). In Reanimationsszenarien führte u.a. die Verzögerung der Rhythmusanalyse
(21%) zu Mängeln, während in den restlichen Fallbeispielen die unsichere Nutzung
des ABCDE-Schemas das größte Problem darstellte (43% Trauma, 26%
internistisch).

Schlussfolgerung Nutzung des ABCDE-Schemas sowie die konsequente
Durchführung von Basismaßnahmen in der Reanimation sind Defizite des
Rettungsfachpersonals und sollten sich in der Schwerpunktsetzung der Ausbildung
wiederfinden.
„Was Krankheiten uns sagen möchten“
Authors: Reißig Uwe
Published: August 2021

Während unsere moderne schulmedizinische Sichtweise hauptsächlich auf die pragmatische Identifikation von Symptomen und deren „Beseitigung” fokussiert ist, bleibt häufig die Frage nach dem Ursprung der Symptomatik offen, was bei zahlreichen Erkrankungen des Kindes- und Jugendalters zu einem langfristig unbefriedigenden Ergebnis und häufigen Rezidiven führt. Im Sinne einer ganzheitlichen Betrachtung der Patienten und deren familiärer, psychosozialer Umstände kann die Methode der Familienaufstellung einen wichtigen Beitrag leisten, diversen Erkrankungen auf den Grund zu gehen und somit möglicherweise eine dauerhafte Besserung zu bewirken.
KiT – Kinder in Trennungsprozessen
Authors: Weiß Annegret , Funke Sebastian
Published: August 2021

Das komplexe Geschehen einer elterlichen Trennung ist für Kinder meist nicht vollständig zu begreifen. Besonders wenn Kinder bei anhaltenden Konflikten der getrennten Eltern zum Gegenstand von Auseinandersetzungen gemacht werden, zeigen sich häufig Reaktionsweisen, die sich für den Kinderarzt als Verhaltensauffälligkeiten und/oder psychosomatische Erscheinungen wie beispielsweise chronische Bauch- oder Kopfschmerzen äußern können. Es liegt am behandelnden Pädiater, diese auch nach lange zurückliegender Trennung korrekt zuzuordnen und geeignete Behandlungsmaßnahmen zu finden. Eine Familientherapie in Form von Einzel- und Gruppensitzungen kann betroffenen Kindern nachhaltig bei der Trennungsverarbeitung und Krisenbewältigung helfen und soll die Elternteile, für die mit ihrem feindseligen Verhalten in Zusammenhang stehenden vielschichtigen Probleme und Folgeerscheinungen sensibilisieren.
Medikamentöse Therapie des primären Knochenmarködemsyndroms
Authors: Delsmann Maximilian M. , Schmidt Constantin , Stürznickel Julian , Barvencik Florian
Published: August 2021

Die medikamentöse Therapie des primären Knochenmarködemsyndroms (KMÖS) stellt einen wesentlichen Bestandteil des Gesamttherapiekonzeptes des KMÖS dar, wobei eine frühe Detektion und eine zeitnahe Initiierung von therapeutischen Maßnahmen von entscheidender Bedeutung ist. Zunächst gilt es, neben dem Ausschluss von sekundären Ursachen, mögliche Störungen der Kalziumhomöostase zu untersuchen und ggf. auszugleichen, da von einem maßgeblichen Einfluss dieser Faktoren in der Pathogenese des primären KMÖS ausgegangen wird. So stellen Mangelzustände, wie ein Vitamin-D-Mangel, eine häufige Ursache einer solchen Störung der Kalziumhomöostase dar und können konsekutiv zu einer enteralen Kalziumaufnahmestörung sowie zu einer Mineralisationsstörung des Knochens führen. Da ein KMÖS häufig mit einem systemischen respektive lokalen High-Turnover-Knochenstoffwechsel einhergeht, ist die Steuerung des Knochenstoffwechsels im Rahmen der Therapie besonders wichtig. Im Falle eines High-Turnover-Knochenstoffwechsels oder anderer klinischer Faktoren, wie einer gelenknahen subchondralen Lokalisation des Knochenmarködems mit Risiko einer Infraktion, einer schnellen Progredienz, einem großen Volumen oder ausgeprägten, immobilisierenden Schmerzen, kann eine antiresorptive Therapie im Off-Label-Verfahren in die Behandlung integriert werden. So konnte für den Einsatz von intravenösen Bisphosphonaten, wie Ibandronat oder Zoledronat, als auch des subkutan zu injizierenden Denosumab eine klinisch relevante Effektivität festgestellt werden, wobei bei Letzterem der schnellste Wirkeintritt zu erwarten ist. Zoledronat scheint, allerdings auf Kosten einer höheren Anzahl potenziell unerwünschter Ereignisse, das effektivste Wirkprofil zu besitzen. Einen alternativen Therapieansatz stellt der Off-Label-Einsatz des Prostazyklin-Analogons Iloprost dar, welches gemäß der Studienlage eine probate Therapieoption in frühen Stadien des Knochenmarködems darstellt, allerdings unter stationärer Überwachung zu applizieren ist. Parallel zur medikamentösen Therapie ist die chirurgische Mitbehandlung mit regelmäßiger Evaluation zur Anbohrung (Core Decompression) als Teil des Gesamttherapiekonzeptes zu eruieren.
Positionspapier - Für strukturelle Reformen, stabile Finanzen und klare Aufgabenverteilung
Authors:   Nach Angaben des GKV-Spitzenverbands
Published: August 2021

Die gesetzliche Krankenversicherung versichert und versorgt 73 Millionen Menschen in Deutschland. Das sind 90 % der Bevölkerung. Mit Blick auf die Sicherung und Weiterentwicklung der gesundheitlichen und pflegerischen Versorgung dieser Menschen hat der Verwaltungsrat des GKV-Spitzenverbandes seine „Positionen für die 20. Legislaturperiode 2021–2025“ beschlossen.
Synchrones Auftreten der klinischen Varianten: Pemphigus vegetans Typ Neumann und oraler Pemphigus vulgaris – eine seltene Variante
Authors: Burkhart Florian , Sohl Falk , Sawallich Katharina , von den Driesch Peter
Published: August 2021

Wir berichten über einen Fall synchronen Auftretens zweier Varianten derselben Grunderkrankung: Pemphigus vegetans Typ Neumann und oraler Pemphigus vulgaris. Diese Manifestationskombination wurde bisher in der Literatur nur selten beschrieben. Eine 52-jährige Patientin stellte sich mit schmerzhaften Blasen an der Mundschleimhaut vor, welche die Nahrungsaufnahme massiv einschränkten. Enoral, labial sowie pharyngeal zeigten sich flächige, krustig belegte Erosionen sowie Exulzerationen. Inguinal bestanden konfluierende, bräunliche, derb-papillomatöse Plaques. Die entnommenen Probebiopsien zeigten in der oralen Epidermis eine Akanthose, Spongiose und intraepitheliale Exozytose von Granulozyten. Inguinal zeigte sich eine Hyperparakeratose, Pseudoepitheliomatose und gemischtzelliges Entzündungsinfiltrat mit zahlreichen eosinophilen Granulozyten mit epithelialer Exozytose der Granulozyten und Lymphozyten. In der direkten Immunfluoreszenz zeigte sich das Bild einer Pemphigus-Erkrankung. Die indirekte Immunfluoreszenz zeigte zirkulierende Antikörper gegen epidermale interzelluläre Antigene. Die durchgeführten apparativen sowie laborchemischen Untersuchungen ergaben keinen Hinweis auf einen malignen Prozess. Wir diagnostizierten einen Pemphigus vulgaris oral sowie einen Pemphigus vegetans Typ Neumann inguinal. Systemisch erfolgte zunächst ein Steroidstoß mittels Methylprednisolon sowie im Verlauf die Einleitung einer Dauertherapie mit Mycophenolat-Mofetil. Lokal applizierten wir Lokalanästhetika, Antimykotika, Antiseptika sowie topische Steroide. Unter der Therapie kam es zu einem ausgezeichneten Ansprechen, sodass die Patientin bereits nach wenigen Tagen wieder feste Nahrung zu sich nehmen konnte. Auch inguinal zeigte sich eine rasche Besserung durch Abflachen der Plaques.

Unser Fall zeigt, dass bei derselben Patientin die klinischen Varianten Pemphigus vegetans Typ Neumann und Pemphigus vulgaris synchron vorliegen können, wobei die orale Beteiligung die für den Pemphigus vegetans beschriebene Stomatitis und Bläschenbildung übersteigt.
Tetrabutylammonium Iodide Mediated Sulfenylation of Poly­substituted 1H-Pyrazol-5-amines with Arylsulfonyl Hydrazides
Authors: Dai Bin , Liu Ping , He Jing , Wei Yueting , Li Xuezhen
Published: August 2021

A TBAI-mediated sulfenylation of N,3-diaryl-1-arylsulfonyl-1H-pyrazol-5-amines with arylsulfonyl hydrazides has been established, and an expanded inventory of N,5-diaryl-4-(arylthio)-1H-pyrazol-3-amines was constructed through C–S bond formation and N–S bond breaking. Mechanistic investigations suggest thiosulfonate as a key intermediate in the sulfenylation, and the detosylation is promoted by the generated arylsulfinic acid. The method is characterized by simple operating conditions, broad substrate range as well as gram-scale reaction.
Recent Advances in Transition-Metal-Catalyzed C–H Addition to Nitriles
Authors: Liao Wei-Wei , Cui Shu-Qiang
Published: August 2021

Transition-metal-catalyzed C–H bond addition to nitriles has emerged as a powerful synthetic approach for the construction of C–C bonds in organic synthesis. Due to the merits of atom- and step-economy, as well the easy availability of the starting materials, these transformations not only deliver acyclic aryl ketone products with nitriles­ as C-building blocks, but can also be utilized for the highly efficient­ assembly of azaheterocyclic skeletons using nitriles as C–N building blocks. This short review summarizes recent progress on transition-metal-catalyzed C–C bond-forming reactions based on C(sp2)–H and C(sp3)–H additions to nitriles.

1 Introduction

2 Palladium-Catalyzed C–H Addition to Nitriles

2.1 Palladium-Catalyzed C–H Addition to Nitriles for the Preparation of Ketone (Imine) Products

2.2 Palladium-Catalyzed C–H Addition to Nitriles for the Preparation of Azaheterocycles

2.3 Palladium-Catalyzed C–H Addition to Nitriles/1,2-Rearangement

3 Other Transition-Metal-Catalyzed C–H Additions to Nitriles

4 Summary and Outlook
Improving laser power stability with a photosensitive lens
Authors: Guan Xiaolei , Zhang Tongyun , Shang Haosen , Pan Duo , He Jin , Pan Jun , Chen Jingbiao
Published: August 2021

We propose a method to improve relative laser power stability using a passive photosensitive sunglass lens, which is a commercially available off-the-shelf product. We present a theoretical analysis and identify factors that affect the optimal working state of the lens. A relative laser power stability of 3.3 × 10−5 at 1 s is experimentally achieved, which is more than three times that of 1.2 × 10−4 at 1 s, acquired without power stabilization. This method does not require any active driving device, thereby significantly reducing the complexity and cost of the system, making it suitable for broad applications.
A deep learning based prediction approach for the supercritical airfoil at transonic speeds
Authors: Sun Di , Wang Zirui , Qu Feng , Bai Junqiang
Published: August 2021

In traditional ways, the aerodynamic property of the aircraft is obtained by solving Navier-Stokes equations or performing tunnel experiments. However, these methods are time consuming for the aircraft design and optimization. In comparison, the deep learning technique is capable of handling high dimensional parameters and can describe compressible flow structures clearly and efficiently. For these, an efficient and accurate prediction approach based on the deep neural network is proposed for the compressible flows over the transonic airfoils in this study. By investigating the effects of the input coordinate features of the deep learning method on the prediction accuracy and robustness, the aerodynamic characteristics, such as lift, drag, and pitch coefficients, are obtained from the predicted flow fields. Results indicate that the proposed deep learning prediction method is with a high resolution and efficiency. It is promising to be extended to the optimization and design process of the supercritical airfoil.
Long-term trends in wildfire damages in California
Authors: Buechi Hanna , Weber Paige , Heard Sarah , Cameron Dick , Plantinga Andrew J.
Published: August 2021

In 2017 and 2018, wildfires in California burned millions of hectares and caused billions of dollars in structure damages. This paper puts these recent fires in a long-term historical context by assembling four decades of data on wildfires in California. We combine administrative data of structure loss due to wildfire with economic data on replacement costs and spatial data on fire locations and sizes. We find that over the period 1979–2018, wildfires in California have been getting larger and that the trend is accelerating. This same trend is seen in the wildland–urban interface. As well, total structure damage from wildfires has grown steadily during the past four decades. Our conclusion is that the recent California fires are not an anomaly, but rather part of a trend towards larger and increasingly destructive wildfires.
TET2 as a tumor suppressor and therapeutic target in T-cell acute lymphoblastic leukemia
Authors: Bensberg Maike , Rundquist Olof , Selimović Aida , Lagerwall Cathrine , Benson Mikael , Gustafsson Mika , Vogt Hartmut , Lentini Antonio , Nestor Colm E.
Published: August 2021

Significance

Pediatric T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy in need of novel targeted therapies to prevent relapse and lessen treatment toxicity. We reveal frequent (∼88%) transcriptional silencing or repression of the tumor suppressor
TET2
in T-ALL. We show that loss of
TET2
in T-ALL is correlated with hypermethylation of the
TET2
promoter and that
TET2
expression can be rescued by treatment with the DNA demethylating agent, 5-azacytidine (5-aza). We further reveal that the TET2 cofactor vitamin C exerts a strong synergistic effect on global transcriptional changes when added to 5-aza treatment. Importantly, 5-aza treatment results in increased cell death, specifically in T-ALL cells lacking TET2. Thus, we clearly identify 5-aza as a potentially targeted therapy for
TET2
-silenced T-ALL.
Capturing shrinkage and neck growth with phase field simulations of the solid state sintering
Authors: Ivannikov Vladimir , Thomsen Fritz , Ebel Thomas , Willumeit-Römer Regine
Published: August 2021

The suitability of the phase field method for the simulation of the evolution of the microstructure during sintering, which has been assumed for more than a decade, receives new impetus from the progress described in this paper. A zero force formulation for the calculation of the rigid body motion of powder particles is adapted to diffuse interface model of Cahn–Hilliard and Allen–Cahn type. In this approach, the rigid body motion ensures the mechanical equilibrium in the powder compound. For this aim, the derivative of the free energy with respect to the additional degree of freedom of rigid body motion was approximated by a force in the grain boundary caused by concentration differences there. The potential of the model is demonstrated by first 2D simulations. These are compared with 2D simulations results generated with a model, which previously showed good agreement with experimentally obtained sintering data in the 3D case. In this comparison good agreements are observed qualitatively as well as quantitatively, showing the plausibility of the new approach.
Geometric aspects of two- and threepeakons
Authors: Cieślak Tomasz , Kryński Wojciech
Published: August 2021

We apply geometric tools to study dynamics of two- and threepeakon solutions of the Camassa–Holm equation. New proofs of asymptotic behavior of the solutions are given. In particular we recover well-known collision conditions. Additionally the Gauss curvature (in the twopeakon case) and the sectional curvature (in the threepeakon case) of corresponding manifolds are computed.
Monotonicity of entropy for real quadratic rational maps
Authors: Filom Khashayar
Published: August 2021

The monotonicity of entropy is investigated for real quadratic rational maps on the real circle

R
∪

{

∞

}

based on the natural partition of the corresponding moduli space

M

2

(

R

)

into its monotonic, covering, unimodal and bimodal regions. Utilizing the theory of polynomial-like mappings, we prove that the level sets of the real entropy function

h

R

are connected in the (−+−)-bimodal region and a portion of the unimodal region in

M

2

(

R

)

. Based on the numerical evidence, we conjecture that the monotonicity holds throughout the unimodal region, but we conjecture that it fails in the region of (+−+)-bimodal maps.
The defect of toral Laplace eigenfunctions and arithmetic random waves
Authors: Kurlberg Pär , Wigman Igor , Yesha Nadav
Published: August 2021

We study the defect (or ‘signed area’) distribution of standard toral Laplace eigenfunctions restricted to shrinking balls of radius above the Planck scale, either for deterministic eigenfunctions averaged w.r.t. the spatial variable, or in a random Gaussian scenario (‘arithmetic random waves’). In either case we exploit the associated symmetry of the eigenfunctions to show that the expectation (spatial or Gaussian) vanishes. In the deterministic setting, we prove that the variance of the defect of flat eigenfunctions, restricted to balls shrinking above the Planck scale, vanishes for ‘most’ energies. Hence the defect of eigenfunctions restricted to most of the said balls is small. We also construct ‘esoteric’ eigenfunctions with large defect variance, by choosing our eigenfunctions so that to mimic the situation on the hexagonal torus, thus breaking the symmetries associated to the standard torus. In the random Gaussian setting, we establish various upper and lower bounds for the defect variance w.r.t. the Gaussian probability measure. A crucial ingredient in the proof of the lower bound is the use of Schmidt’s subspace theorem.
Weak–strong uniqueness property for models of compressible viscous fluids near vacuum*
Authors: Feireisl Eduard , Novotný Antonín
Published: August 2021

We extend the weak–strong uniqueness principle to general models of compressible viscous fluids near/on the vacuum. In particular, the physically relevant case of positive density with polynomial decay at infinity is considered.
Observation of the high-density front at the high-field-side in the J-TEXT tokamak
Authors: Shi Peng , Sun Hongjuan , Zhuang Ge , Cheng Zhifeng , Gao Li , Chen Zhipeng , Li Jingchun , Zhou Yinan , Zhou Chengxi
Published: August 2021

This article reports the observation of the high-density front at the high field side (HFS) region in the limiter J-TEXT tokamak. In the J-TEXT high density discharges, the high-density front at the HFS scrape-off layer (SOL) region has been clearly identified by the far-infrared laser polarimeter-interferometer. The high-density front forms at the HFS SOL when the plasma density reaches a critical value, it can be up to seven times higher than the density in the low field side region and it stays stable as long as the density remains. In this stable phase, the local radiation is at a low level and it shares common characteristics with the high-field-side high-density (HFSHD) phenomena observed in divertor devices. If density increases continuously, the high-density front expands poloidally and evolves into an unstable ‘moving’ phase while propagating into the main plasma region, which eventually triggers the disruption. The maximum achievable density on J-TEXT seems to be correlated with the evolution of the high-density front, suggesting that the region may play a role in setting the operational limit on J-TEXT. The unstable phase of high-density front seems to share some common characteristics with the well-known multifaceted asymmetric radiation from the edge (MARFE), except that the radiation level in J-TEXT stays at a low level. The density threshold of the high-density front formation and the maximum density of the region itself increase with

I

P

, consistent with the observation on both HFSHD and MARFE. The MARFE-like behavior of the high-density front in its final stage, suggests that MARFEs might be the result of these fronts forming in or moving into regions where the plasma temperature and impurity concentration are conducive for them to be radiatively unstable.
Revealing the A1g-type strain effect on superconductivity and nematicity in FeSe thin flake*
Authors: Cheng Zhaohui , Lei Bin , Luo Xigang , Ying Jianjun , Wang Zhenyu , Wu Tao , Chen Xianhui
Published: August 2021

The driving mechanism of nematicity and its twist with superconductivity in iron-based superconductors are still under debate. Recently, a dominant B1g-type strain effect on superconductivity is observed in underdoped iron-pnictides superconductors Ba(Fe1–x
Co
x
)2As2, suggesting a strong interplay between nematicity and superconductivity. Since the long-range spin order is absent in FeSe superconductor, whether a similar strain effect could be also observed or not is an interesting question. Here, by utilizing a flexible film as substrate, we successfully achieve a wide-range-strain tuning of FeSe thin flake, in which both the tensile and compressive strain could reach up to ∼0.7%, and systematically study the strain effect on both superconducting and nematic transition (T
c and T
s) in the FeSe thin flake. Our results reveal a predominant A1g-type strain effect on T
c. Meanwhile, T
s exhibits a monotonic anti-correlation with T
c and the maximum T
c reaches to 12 K when T
s is strongly suppressed under the maximum compressive strain. Finally, in comparison with the results in the underdoped Ba(Fe1–x
Co
x
)2As2, the absence of B1g-type strain effect in FeSe further supports the role of stripe-type spin fluctuations on superconductivity. In addition, our work also supports that the orbital degree of freedom plays a key role to drive the nematic transition in FeSe.
Differential nonlinear photocarrier radiometry for characterizing ultra-low energy boron implantation in silicon
Authors: Lei Xiao-Ke , Li Bin-Cheng , Sun Qi-Ming , Wang Jing , Gao Chun-Ming , Wang Ya-Fei
Published: August 2021

The measuring of the depth profile and electrical activity of implantation impurity in the top nanometer range of silicon encounters various difficulties and limitations, though it is known to be critical in fabrication of silicon complementary metal–oxide–semiconductor (CMOS) devices. In the present work, SRIM program and photocarrier radiometry (PCR) are employed to monitor the boron implantation in industrial-grade silicon in an ultra-low implantation energy range from 0.5 keV to 5 keV. The differential PCR technique, which is improved by greatly shortening the measurement time through the simplification of reference sample, is used to investigate the effects of implantation energy on the frequency behavior of the PCR signal for ultra-shallow junction. The transport parameters and thickness of shallow junction, extracted via multi-parameter fitting the dependence of differential PCR signal on modulation frequency to the corresponding theoretical model, well explain the energy dependence of PCR signal and further quantitatively characterize the recovery degree of structure damage induced by ion implantation and the electrical activation degree of impurities. The monitoring of nm-level thickness and electronic properties exhibits high sensitivity and apparent monotonicity over the industrially relevant implantation energy range. The depth profiles of implantation boron in silicon with the typical electrical damage threshold (Y
ED) of 5.3 × 1015 cm−3 are evaluated by the SRIM program, and the determined thickness values are consistent well with those extracted by the differential PCR. It is demonstrated that the SRIM and the PCR are both effective tools to characterize ultra-low energy ion implantation in silicon.
High-pressure Raman study of osmium and rhenium up to 200 GPa and pressure dependent elastic shear modulus C
44
Authors: Liu Jingyi , Tao Yu , Fan Chunmei , Wu Binbin , Tang Qiqi , Lei Li
Published: August 2021

High-pressure Raman scattering from hexagonal close-packed (HCP) metals Os and Re have been extended up to 200 GPa, and the pressure-dependent shear modulus C
44 has been deduced from the Raman-active mode E
2g
, which is generated from the adjacent vibration of atoms in hexagonal planes, providing the valuable information about the elastic properties for HCP metals under high pressure. Combined with the available data of HCP metals from previous works, a further study indicates that the

C

44

′

/

C

44

ratio would be close to a constant value, 0.01, with increasing atomic number of metals. The results obtained from high-pressure Raman scattering will allow us to probe the elastic anisotropy of the HCP metals at very high pressure.
Synthetical optimization of the structure dimension for the thermoacoustic regenerator
Authors: Kang Huifang , Zhang Lingxiao , Shen Jun , Ding Xiachen , Li Zhenxing , Liu Jun
Published: August 2021

The quantitative investigation of parameters in the renegerator is essential for the optimization of thermoacoustic devices, while the majority of the previous research only considered parameters of the working field, working gas and the hydraulic radius. Based on the linear thermoacoustic theory, this paper extracts a normalized parameter for low-amplitude conditions, which is called the regenerator operation factor. By extracting the regenerator operation factor and relative hydraulic radius, the influence of frequency on the efficiency can be controlled and offset. It can be found that thermoacoustic devices with different frequencies can perform the same efficiency by adjusting the radius in proportion to the axial length. Finally, this paper synthetically optimizes the dimension of the thermoacoustic regenerator by taking the regenerator operation factor, relative hydraulic radius and acoustic field parameter as variables. Conclusions in this paper are of great significance for explaining the best working conditions of engines and directing the miniaturization and optimal design of thermoacoustic devices.
Spectroscopy and scattering matrices with nitrogen atom: Rydberg states and optical oscillator strengths
Authors: Zhu Yuhao , Jin Rui , Wu Yong , Wang Jianguo
Published: August 2021

The scattering matrices of e + N+ with Jπ
= 1.5+ in discrete energy regions are calculated using the eigenchannel R-matrix method. We obtain good parameters of multichannel quantum defect theory (MQDT) that vary smoothly as the function of the energy resulting from the analytical continuation property of the scattering matrices. By employing the MQDT, all discrete energy levels for N could be calculated accurately without missing anyone. The MQDT parameters (i.e., scattering matrices) can be calibrated with the available precise spectroscopy values. In this work, the optical oscillator strengths for the transition between the ground state and Rydberg series are obtained, which provide rich data for the diagnostic analysis of plasma.
Induced current of high temperature superconducting loops by combination of exciting coil and thermal switch
Authors: Wang Jia-Wen , Wang Yin-Shun , Chai Hua , Zhu Ling-Feng , Pi Wei
Published: August 2021

With its commercialization, the second-generation (2G) high temperature superconducting (HTS) RE–Ba–Cu–O (REBCO, RE is rare earth) tape is extensively applied to the superconducting magnets in the high magnetic fields. However, unlike low temperature superconducting (LTS) magnets, the HTS magnet cannot operate in the persistent current mode (PCM) due to the immature superconducting soldering technique. In this paper, an exciting method for two HTS sub-loops, so-called charging and load loops, is proposed by flux pump consisting of exciting coil and controllable thermal switch. Two HTS sub-loops are made of an REBCO tape with two slits. An exciting coil with iron core is located in one sub-loop and is supplied with a triangular waveform current so that magnetic field is generated in another sub-loop. The influence of magnetic flux on induced current in load loop is presented and verified in experiment at 77 K. The relationship between the induced magnetic flux density and the current on the sub-loops having been calibrated, magnetic flux density, and induced current are obtained. The results show that the HTS sub-loops can be excited by a coil with thermal switch and the induced current increases with magnetic flux of exciting coil increasing, which is promising for persistent current operation mode of HTS magnets.
Evolution of defects and deformation mechanisms in different tensile directions of solidified lamellar Ti–Al alloy
Authors: Liu Yutao , Gao Tinghong , Gao Yue , Li Lianxin , Tan Min , Xie Quan , Chen Qian , Tian Zean , Liang Yongchao , Wang Bei
Published: August 2021

Two-phase γ-TiAl/α
2-Ti3Al lamellar intermetallics have attracted considerable attention because of their excellent strength and plasticity. However, the exact deformation mechanisms remain to be investigated. In this paper, a solidified lamellar Ti–Al alloy with lamellar orientation at 0°, 17°, and 73° with respect to the loading direction was stretched by utilizing molecular dynamics (MD) simulations. The results show that the mechanical properties of the sample are considerably influenced by solidified defects and tensile directions. The structure deformation and fracture were primarily attributed to an intrinsic stacking fault (ISF) accompanied by the nucleated Shockley dislocation, and the adjacent extrinsic stacking fault (ESF) and ISF formed by solidification tend to form large HCP structures during the tensile process loading at 73°. Moreover, cleavage cracking easily occurs on the γ/α
2 interface under tensile deformation. The fracture loading mechanism at 17° is grain boundary slide whereas, at 73° and 0°, the dislocation piles up to form a dislocation junction.
Multi-scale interactions between turbulence and magnetohydrodynamic instability driven by energetic particles
Authors: Ishizawa A. , Imadera K. , Nakamura Y. , Kishimoto Y.
Published: August 2021

In order to realize high performance burning plasmas in magnetic-confinement fusion devices, such as tokamaks, both bulk plasma transport and that of energetic fusion alpha-particles, which result from different scale fluctuations with different free energy sources, have to be reduced simultaneously. Utilizing the advantage of global toroidal non-linear simulations covering a whole torus, here, we found a new coupling mechanism between the low-frequency micro-scale electromagnetic drift-wave fluctuations regulating the former, while the high-frequency macro-scale toroidal Alfven eigenmode (TAE) regulates the latter. This results from the dual spread of micro-scale turbulence due to the macro-scale TAE not only in wavenumber space representing local eddy size but also in configuration space with global profile variations. Consequently, a new class of turbulent state is found to be established, where the turbulence is homogenized on the poloidal cross-section with exhibiting large-scale structure, which increases fluctuation levels and then both transports, leading to deterioration in the fusion performance.
Radar hybrid signal generators based on high-speed digital-to-analog converters
Authors: Romashov V V , Yakimenko K A , Doktorov A N , Groshkov I D
Published: August 2021

Wideband frequency synthesizers are used in many different applications, such as radars, telecommunications and others. Radar parameters are dependent on the synthesizers phase noise. A general flow-chart of a hybrid frequency synthesizer based on direct digital and direct analog synthesis methods that uses a high-speed digital-to-analog converter (DAC) in special operating modes to increase the operating frequency is presented in this paper. The noise characteristics of a hybrid synthesizer with a DAC operating in two modes are simulated.
Recurrent pattern of extreme fire weather in California
Authors: Son Rackhun , Wang S-Y Simon , Kim Seung Hee , Kim Hyungjun , Jeong Jee-Hoon , Yoon Jin-Ho
Published: August 2021

Historical wildfire events in California have shown a tendency to occur every five to seven years with a rapidly increasing tendency in recent decades. This oscillation is evident in multiple historical climate records, some more than a century long, and appears to be continuing. Analysis shows that this 5–7 year oscillation is linked to a sequence of anomalous large-scale climate patterns with an eastward propagation in both the ocean and atmosphere. While warmer temperature emerges from the northern central Pacific to the west coast of California, La Niña pattern develops simultaneously, implying that the lifecycle of the El Niño-Southern Oscillation that takes multiple years to form could be a trigger. The evolving patterns of the Pacific-to-North America atmospheric teleconnection suggest the role of tropical and subtropical forcing embedded in this lifecycle. These results highlight the semi-cyclical hydrological behavior as a climate driver for wildfire variability in California.
The Validity of Internal Support and Facilitating Content on Sustainable Green Building Management in Indonesia
Authors: Retno D P , Wibowo M A , Hatmoko J U D
Published: August 2021

The operation and maintenance phase is one of the most important and longest phase in the green building life cycle. In this phase, the existence of internal support and facilitating that is oriented towards sustainable green management can have a major impact on building performance. Its existence is both a support and a catalyst for other processes to be undertaken during this phase. This study aims to assess the content validity in the preparation of a questionnaire for the assessment instrument for internal support and facilitating of sustainable green management, particularly the operation and maintenance phase of buildings in Indonesia. Internal support and facilitation is divided into 3 key variables in this research: leadership, policy, and people. Meanwhile, the study stage consists of instrument design, expert panel determination, and content validity quantification. The method used in the content validity analysis consists of: I-CVI, S-CVI, CVR and Kappa statistical coefficient. Based on the results of the study, the number of indicators that meet the requirements is as follows: four indicators on the leadership variable, six indicators on the policy variable and five indicators for the people variable.
Pedestrian Perception Based on Sidewalk Level of Convenience at Pemuda Street
Authors: Arifah S , Hidayah R
Published: August 2021

The city of Jakarta is one of the largest metropolitan cities in Indonesia. Urban development is often oriented towards transportation systems with two-wheeled and four-wheeled vehicles. If there is little space for pedestrians, it cannot provide benefits and advantages for pedestrians. This study uses a descriptive quantitative approach, where data collection is carried out through surveys with observations and questionnaires. Google form-based questionnaires were given to respondents classified according to gender who passed the Pemuda Street pedestrian path, this was due to conditions in the field that made it impossible to meet many people during the Covid-19 pandemic. The sampling technique used in this study was random sampling. The results showed 156 respondents with a percentage of 68.12% of respondents stated that the Pemuda pedestrian path was comfortable for pedestrians to pass. This is supported by several indicator factors, from some of these indicators, it can be seen that the indicators of the surface condition of the pedestrian pathway at Pemuda Street, both men and women, feel comfortable with a percentage of 78.93% and 75.08%, but the indicators of Obstacle / obstruction on the pedestrian pathway Youth, both male and female, felt uncomfortable with a percentage of 52.33% and 49.58%.
Effect of Rod Diameter and Adhesive Thickness to the Pull-out Strength of Threaded Steel Rod Glued in Laminated Bamboo
Authors: Dewi M D K , Karyadi  , Susanto P B , Nindyawati
Published: August 2021

The purpose of this study was to determine the effect of threaded steel rod diameter and adhesive thickness on pull-out strength, shear strength, slip modulus, and damage patterns of glued-in rod embedded in laminated bamboo. The shape of the specimen is a cube with the dimensions of 100mm × 100mm × 100mm made of laminated Asian Bamboo (Dendrocalamus asper). The threaded steel rod diameter consists of three sizes, namely 8mm, 10mm, and 12mm. Each threaded steel rod is embedded in laminated bamboo to a 40mm length. The epoxy brand Sikadur 372 is used as an adhesive between laminated bamboo and threaded steel rods with three variations of adhesive thickness, namely 2mm, 3mm, and 4mm. Each variation of the test object was repeated five times. The results showed that the rod diameter and adhesive thickness affect the pull-out strength, shear strength, and slip modulus.