bluuebunny/crossref_metadata_2025 huggingface dataset:
Komplexe mikrochirurgische Rekonstruktionen und ihre gebührenrechtliche Abbildung im antiquierten Vergütungssystem der GOÄ
Authors: Germann Günter , Allert Sixtus
Published: August 2020

Die Gebührenordnung für Ärzte (GOÄ) ist die Grundlage für die Abrechnung privatärztlicher Leistungen. Die letzte Teilnovellierung für Leistungen im operativen Bereich erfolgte 1996. Dies führt dazu, dass die Fortschritte in den operativen Fächern völlig unzureichend abgebildet sind, neue Operationen überhaupt nicht vorkommen und viele der aufgeführten Verfahren heute gar nicht mehr durchgeführt werden.

Auch mikrochirurgische Operationsverfahren finden sich nicht in der GOÄ. Daraus resultieren bei der privatärztlichen Abrechnung permanente Konflikte mit den privaten Krankenversicherern, die eine adäquate Abrechnung dieser komplexen Operationsverfahren mit Hinweisen auf bestehende Leistungsziffern teilweise veralteter Verfahren und einer selbst zuerkannten Interpretationshoheit der GOÄ zu verhindern suchen.

Zu dieser Problematik hat der BGH 2007 eine Entscheidung gefällt, in der ausgeführt wird, dass Verfahren, die nicht in der GOÄ abgebildet sind, durch Ziffern vergleichbaren Schwierigkeitsgrades und Zeitaufwands abgerechnet werden können. Aber auch dieses Urteil hat nicht zu einer Klärung bei der Abrechnung beigetragen, sondern wird von den PKVen regelmäßig negiert.

Der folgende Artikel soll einen Beitrag zur Lösung dieses Dilemmas leisten, indem er die immer wieder strittigen Leistungsziffern diskutiert und ihre Anwendungen mit rechtskräftigen Urteilen unterlegt.
Zur Therapie von Phylloides-Tumoren der Brust – eine Aufarbeitung von 66 Fällen mit Literaturübersicht
Authors: Lohmeyer Jörn Andreas , Huster Nora , Lühr Clara , Lindner Christoph , Wittig Klaus Stephan , Keck Maike Katharina
Published: August 2020

Phylloides-Tumore (PT) der Brust werden anhand der Konstellation definierter histologischer Parameter als benigne, borderline und maligne klassifiziert. Die chirurgische Exzision ist die primäre Therapie, aber die Notwendigkeit zur Einhaltung bestimmter Sicherheitsabstände wird für alle drei Kategorien kontrovers diskutiert. Ziel der Arbeit ist eine kritische Stellungnahme zur bestehenden Empfehlung zu Sicherheitsabständen der Resektion.

In unserem Brustzentrum wurden retrospektiv anhand der histopathologischen Dokumentationen von 1999 bis 2018 alle Patientinnen mit Phylloides-Tumoren identifiziert und die Fälle insbesondere hinsichtlich des Auftretens von Rezidiven und Multizentrizität ausgewertet.

Insgesamt wurde bei 66 Patientinnen die Diagnose eines PT gestellt. Dabei handelte es sich in 38 Fällen um benigne, in 15 um borderline und in 13 um maligne Tumore. Lokalrezidive traten bei einem benignen PT, 7 borderline und 5 malignen PT auf. Zwei initiale borderline PT zeigten dabei eine Progression zu malignen PT. Multizentrizität trat in etwa 20 % der borderline und malignen PT aber nur bei 5 % der benignen PT auf.

Die Resektionsgrenzen bei Phylloides-Tumoren sollten abhängig von Dignität und Rezidivierung gewählt werden. In Frage zu stellen ist vor allem, ob ein Sicherheitsabstand bei benignen PT einzuhalten ist. Bei einem Auftreten von Rezidiven von borderline oder malignen PT sollte die Indikation zur Mastektomie eher großzügig gestellt werden.
Behandlung der leichten Clostridioides-difficile-Infektion – hat Metronidazol noch einen Stellenwert?
Authors: Stallmach Andreas , Katzer Katrin , Reuken Philipp
Published: August 2020

Clostridioides-difficile-Infektionen (CDI) sind typische Komplikationen einer Antibiotikatherapie. Wenn auch die durch C. diff. verursachten Krankheitsbilder bis zum toxischen Megakolon mit letalen Verläufen reichen können, sind leichte Verlaufsformen mit unkomplizierter Diarrhoe bei Weitem am häufigsten. Auch die Behandlung dieser Krankheitsbilder sollte leitliniengerecht erfolgen. Die zurzeit gültigen internationalen Leitlinien sind bezüglich der Therapie der leichten Infektion mit Metronidazol aber widersprüchlich. Vor diesem Hintergrund erfolgte eine selektive Literaturrecherche zu Leitlinien und Behandlungsstudien zum Einsatz von Metronidazol bei leichter CDI. Die Auswertung randomisierter kontrollierter Studien zeigt eine statistische Überlegenheit von Vancomycin gegenüber Metronidazol (NNT 16). Unter Einbeziehung großer Kohortenstudien reduziert sich dieser Unterschied in der Effektivität auf 2,5 % (NNT 40). Inkonsistente Kriterien zur Definition einer leichten CDI, unterschiedliche Dosierungen, Applikationen und Zeitintervalle (z. B. zusätzliche Gabe von Metronidazol i. v.) sowie der retrospektive Charakter mancher Studien verhindern das Erkennen möglicher Einflüsse von Störgrößen bei dieser Bewertung. Dennoch kann eine leichte CDI erfolgreich mit Metronidazol behandelt werden; andere Empfehlungen insbesondere amerikanischer Gesellschaften sollten deshalb kritisch bewertet werden. Wichtig ist, dass diese Therapieempfehlung nicht für Patienten mit chronisch entzündlichen Darmerkrankungen oder andere Patienten mit relevanten Komorbiditäten gilt.
Technical Feasibility of Electromagnetic US/CT Fusion Imaging and Virtual Navigation in the Guidance of Spine Biopsies
Authors: Mauri Giovanni , Gitto Salvatore , Pescatori Lorenzo Carlo , Albano Domenico , Messina Carmelo , Sconfienza Luca Maria
Published: August 2020

Purpose To test the technical feasibility of electromagnetic computed tomography (CT) + ultrasound fusion (US)-guided bone biopsy of spinal lesions.

Materials and Methods This retrospective study included 14 patients referred for biopsy of spinal bone lesions without cortical disruption or intervertebral disc infection. Lesions were located in the sacrum (n = 4), lumbar vertebral body (n = 7) or intervertebral disc (n = 3). Fusion technology matched a pre-procedure CT scan with real-time ultrasound. The first six procedures were performed under both standard CT and CT + US fusion guidance (group 1). In the last eight procedures, the needle was positioned under fusion imaging guidance alone, and CT was only used at the end of needle placement to confirm correct positioning (group 2). Additionally, we retrieved 8 patients (controls) with location-matched lesions as group 2, which were biopsied in the past with the standard CT-guided technique. The procedure duration and number of CT passes were recorded.

Results Mean procedure duration and median CT pass number were significantly higher in group 1 vs. group 2 (45 ± 5 vs. 26 ± 3 minutes, p = 0.002 and 7; 5.25–8.75 vs. 3; 3–3.25, p = 0.001). In controls, the mean procedure duration was 47 ± 4 minutes (p = 0.001 vs. group 2; p = 0.696 vs. group 1) and the number of CT passes was 6.5 (5–8) (p = 0.001 vs. group 2; p = 0.427 vs. group 1). No complications occurred and all specimens were adequate overall. In one case in group 2, the needle position was modified according to CT assessment before specimen withdrawal.

Conclusion Electromagnetic CT+US fusion-guided bone biopsy of spinal lesions is feasible and safe. Compared to conventional CT guidance, it may reduce procedural time and the number of CT passes.
Magnetic Resonance Imaging of Diverticular Disease and its Association with Adipose Tissue Compartments and Constitutional Risk Factors in Subjects from a Western General Population
Authors: Storz Corinna , Rospleszcz Susanne , Askani Esther , Rothenbacher Theresa , Linseisen Jakob , Messmann Helmut , De Cecco Carlo N. , Machann Jürgen , Kiefer Lena Sophie , Elser Stefanie , Rathmann Wolfgang , Peters Annette , Schlett Christopher L. , Bamberg Fabian
Published: August 2020

Purpose To determine the association of asymptomatic diverticular disease as assessed by magnetic resonance imaging (MRI) with adipose tissue compartments, hepatic steatosis and constitutional risk factors within a cohort drawn from a Western general population.

Materials and Methods Asymptomatic subjects enrolled in a prospective case-control study underwent a 3 Tesla MRI scan, including an isotropic VIBE-Dixon sequence of the entire trunk. The presence and extent of diverticular disease were categorized according to the number of diverticula in each colonic segment in a blinded fashion. The amount of visceral, subcutaneous, and total adipose tissue (VAT, SAT, and TAT) was quantified by MRI. Additionally, the degree of hepatic steatosis, indicated as hepatic proton density fat fraction (hepatic PDFF) was determined using a multi-echo T1w sequence. Constitutional cardiometabolic risk factors were obtained and univariate and multivariate associations were calculated.

Results A total of 371 subjects were included in the analysis (58.2 % male, 56.2 ± 9.2 years). Based on MRI, 154 participants (41.5 %) had diverticular disease with 62 cases (17 %) being advanced diverticular disease. Subjects with advanced diverticular disease had a significantly higher body mass index (BMI) (BMI: 29.9 ± 5.1 vs. 27.5 ± 4.6, p < 0.001; respectively). Furthermore, all adipose tissue compartments were increased in subjects with advanced diverticular disease (e. g. VAT: 6.0 ± 2.8 vs. 4.2 ± 2.6 and SAT: 9.2 ± 3.6 vs. 7.8 ± 3.6, all p < 0.001, respectively). Similarly, subjects with advanced diverticular disease had significantly higher hepatic PDFF (4.9 [2.7, 11.4] vs. 6.1 [5.5, 14.6], p = 0.002).

Conclusion Advanced diverticular disease is associated with an increased volume of adipose tissue compartments and BMI, which may suggest a metabolic role in disease development.

Key Points:

Citation Format
An HIT Ecosystem Capability Maturity Model for System-Wide Implementation, Management, and Governance
Authors: Shivers Jennifer , Amlung Joseph , Cullen Theresa
Published: August 2020

Background An effective health system is dependent on the people, processes, and technology required to support its successful use. Technology, including essential health information technology (HIT) components, is not enough to successfully support quality patient care delivery. Without a strong support structure, HIT tools and data alone will fail to meet the desired goal of quality patient care that achieves health equity. Multiple factors, including governance processes, policies, and standards, are critical for the development, implementation, and consistent and effective use of clinical HIT systems and the resulting data. A comprehensive model that provided support for a holistic assessment of the HIT ecosystem could not be identified. The Facility HIT Ecosystem Capability Maturity Model (ECMM) was designed in response to this need.

Objectives This project was designed to create and propose a comprehensive framework for self-assessment and support of a maturation pathway for a facility's comprehensive HIT ecosystem, including governance processes, policies, and standards.

Methods Iterative methods based on agile and human-centered design practices were used to create and validate the framework and its contents.

Results The ECMM and toolkit support a health care facility's clinical or technical leadership, including chief medical officers, chief information officers, and chief medical/health/nursing informatics officers, in identifying and assessing policies, processes, and capabilities surrounding HIT. This framework supports iterative evaluation and step-ladder style progression and goal setting to achieve desired capabilities, both at the local level and at the level of supporting organizations. Reviewer feedback was used to provide iterative tool improvement and refinement.

Conclusion The proposed HIT maturity model toolkit showed potential as a tool to help empower health care facilities and their leadership to advance their HIT ecosystem.
Assessment of Hearing Loss in Patients Receiving Chemoradiotherapy in Adjuvant Setting for Head and Neck Malignancy
Authors: Gupta Vani Krishana , Bhat Mahesh , Rao Vinay Vaidyanathan , Surendra Vishak
Published: August 2020

Introduction The aim of the study is to assess the hearing loss in patients who receive chemoradiation (chemoradiotherapy or CTRT) for head and neck malignancies.

Materials and Methods Prospective study was conducted in the Department of ENT of a tertiary care center from September 2013 to August 2014. Forty patients suffering from head and neck malignancies (histologically proven) were included in the study. Patients with pre-existing hearing loss were excluded. All patients received radiotherapy dose of 66 to 70 Gy given as 2 Gy/d, 5 d/wk and chemotherapy dose of cisplatin 35 mg/m2 once a week for 6 weeks. Hearing was assessed by pure tone audiometry (PTA) and impedance audiometry conducted at regular intervals. Mcnemars chi-square test was used to compare the impedance and paired t-test and Pearson’s correlation were used to compare PTA at various stages.

Results Predominantly male patients (28) falling in the age group of 40 to 60 years, suffered from various head and neck cancer, most common being oropharynx (14). Twenty patients developed sensorineural hearing loss (SNHL)—11(55%) had mild, seven (35%) had moderate, and two (10%) had severe grade of SNHL. Majority of these patients, 12 (60%) started developing SNHL mid-therapy, five (25%) at the completion of therapy and three (15%) 3 months post-therapy. Hearing loss was found to be more with two-dimensional radiotherapy (2DRT) and three-dimensional radiotherapy (3DRT) than with intensity-modulated radiotherapy (IMRT) as assessed by serial PTA. The average dose of radiation to right and left ears, respectively were 27.10 and 24.66 Gy. The incidence of otitis media with effusion increased during the treatment accounting for the conductive hearing loss irrespective of the modality of radiation used.

Conclusion CTRT causes significant hearing loss in patients suffering from head and neck malignancies leading to further increase in the morbidity. Screening audiological assessment would be helpful to know the pretherapy status of the ear. Using newer modalities like IMRT can reduce hearing loss. Regular audiological screening can catch it at its onset and help in early use of hearing aids.
A numerical study on efficient jury size
Authors: Watanabe Takamitsu
Published: August 2020

For judicial democracy, many societies adopt jury trials, where verdicts are made by a unanimous vote of, conventionally, 12 lay citizens. Here, using the majority-vote model, we show that such jury sizes achieve the best balance between the accuracy of verdicts and the time spent for unanimous decision-making. First, we identify two determinants of the efficient jury size: the opinion homogeneity in a community decreases the optimal jury size by affecting the accuracy of verdicts; the anti-conformity tendency in the community also reduces the efficient jury size by prolonging the time to reach unanimous verdicts. Moreover, we find an inverse correlation between these two determinants, which prevents over-shrinking and excessive expansion of the efficient jury size. Finally, by applying these findings into real-life settings, we narrow down the efficient jury size to 11.8 ± 3.0. Given that such a simple toy model can explain the jury sizes in the actual societies, the number of jurors may have been implicitly optimised for efficient unanimous decision-making throughout human history.
Sapphire substrates for lithium niobate films promise circuits with broadband applications
Authors: Larter Raima
Published: August 2020

Investigators demonstrate acousto-optics in lithium niobate films on sapphire with bright prospects for monolithic piezoelectric and photonic circuits and systems.
Long-time asymptotics of non-degenerate non-linear diffusion equations
Authors: Christov Ivan C. , Ibraguimov Akif , Islam Rahnuma
Published: August 2020

We study the long-time asymptotics of prototypical non-linear diffusion equations. Specifically, we consider the case of a non-degenerate diffusivity function that is a (non-negative) polynomial of the dependent variable of the problem. We motivate these types of equations using Einstein’s random walk paradigm, leading to a partial differential equation in non-divergence form. On the other hand, using conservation principles leads to a partial differential equation in divergence form. A transformation is derived to handle both cases. Then, a maximum principle (on both an unbounded and a bounded domain) is proved in order to obtain bounds above and below for the time-evolution of the solutions to the non-linear diffusion problem. Specifically, these bounds are based on the fundamental solution of the linear problem (the so-called Aronson’s Green function). Having thus sandwiched the long-time asymptotics of solutions to the non-linear problems between two fundamental solutions of the linear problem, we prove that, unlike the case of degenerate diffusion, a non-degenerate diffusion equation’s solution converges onto the linear diffusion solution at long times. Select numerical examples support the mathematical theorems and illustrate the convergence process. Our results have implications on how to interpret asymptotic scalings of potentially anomalous diffusion processes (such as in the flow of particulate materials) that have been discussed in the applied physics literature.
Three-dimensional simulation of ligament formation and breakup caused by external vibration
Authors: Li Yikai , Zhang Mei , Wu Kun
Published: August 2020

Ligament formation followed by breakup is the primary process that controls external vibration-driven liquid atomization. In this paper, single-mode Faraday instabilities with detailed interfacial dynamics are studied via three-dimensional simulations with a validated numerical methodology. The detailed mechanisms of ligament formation and its breakup are illuminated. Colliding flow from adjacent troughs results in a pressure increase at the root of the crest. This nonlinear flow structure produces a local maximum pressure point that liberates the liquid region above it from the bulk liquid layer that synchronously moves with the bottom substrate. The appearance of the maximum pressure point can thus be recognized as the indicator of ligament formation. The freed ligament with capillary waves on its surface continues to grow until successive breakup occurs at its tip, which is driven by the “short-wave mode” breakup mechanism. It is found that the tip contraction dynamics of Faraday-type ligament can be well described by a one-dimensional theoretical model of a low-speed liquid jet under temporally periodic acceleration. Finally, the development behaviors of Faraday-type ligament and liquid jet are compared quantitatively, which reveals the analogy in their breakup dynamics in the tip regions.
Tunable plexciton dynamics in electrically biased nanojunctions
Authors: Ahmadivand Arash , Gerislioglu Burak
Published: August 2020

Strong coupling between resonantly coordinated plasmonic modes and excitonic states from quantum emitters or analogous two-level systems has led to the realization of pronounced plexciton dynamics. Here, we present and discuss an unconventional approach for this purpose by designing an electrically driven system composed of quantum dots (QDs) trapped in an opening region between two metallic electrodes. By conducting theoretical and numerical investigations, we quantitatively show that under specific bias, radiatively generated plasmons in the device efficiently couple to the excitonic states arisen from quantum emitters in the tunnel. This resulted in pronounced Rabi oscillations and splitting of the classical dipole mode emitted from the tunnel junctions. By computing the local density of states and electroluminescence spectra, we demonstrated the emission of light from the gated system and verified the fundamental parameters of the proposed unique architecture depending on the current flow at the barrier. By taking advantage of the local nature of the excited plasmons and varying the number of QDs in the tunnel, we precisely modeled the plexcitonic coupling and quantified the Rabi splitting of the fundamental resonances around ħΩ ≈ 200 meV. Possessing immense potential to be exploited in devising advanced technologies, we envision that the electrically driven plexciton dynamics brings on-chip ultrafast and ultradense instruments one step closer to reality.
Defect accommodation in off-stoichiometric (SrTiO3)nSrO Ruddlesden–Popper superlattices studied with positron annihilation spectroscopy
Authors: Dawley Natalie M. , Goodge Berit H. , Egger Werner , Barone Matthew R. , Kourkoutis Lena F. , Keeble David J. , Schlom Darrell G.
Published: August 2020

The low dielectric loss underlying the record performance of strained (SrTiO3)nSrO Ruddlesden–Popper films as tunable microwave dielectrics was postulated to arise from (SrO)2 faults accommodating local non-stoichiometric defects. Here, we explore the effect of non-stoichiometry on (SrTiO3)nSrO using positron annihilation lifetime spectroscopy on a composition series of 300 nm thick n = 6 (Sr1+δTiO3)nSrO thin films. These films show titanium-site vacancies across the stoichiometry series, with evidence that TiOx vacancy complexes dominate. Little change in defect populations is observed across the series, indicating the ability of Ruddlesden–Popper phases to accommodate ± 5% off-stoichiometry. This ability for defect accommodation is corroborated by scanning transmission electron microscopy with electron energy loss spectroscopy.
A planar metamaterial based on metallic rectangular-ring pair for narrow electromagnetically induced transparency-like effect
Authors: Yin Xiao-gang , Wu Ming-qi , Liu You-wen , Huang Cheng-ping
Published: August 2020

We design numerically and demonstrate experimentally a planar metamaterial with a narrow band electromagnetically induced transparency (EIT)-like resonance at microwave frequencies. The meta-molecule, consisting of a pair of metallic rectangular rings connected by a top metallic strip, is mirror symmetric with respect to the exciting electric field of the normally incident wave. The coupling between a broad bright mode (electric dipole) of the whole meta-molecule and a sharp dark mode (electric quadrupole) belonging only to the rectangular-ring pair can efficiently induce an ultra-narrow EIT-like resonance. By using a coupled-resonator model that shows good accordance with the numerical and experimental results, the observed effect can be well explained. Our design provides another way to realize the sharp EIT-like behavior with strong dispersion and the slow-wave effect, which may find potential applications in constructing the slow-wave devices, filters, and sensors.
Broadband asymmetric transmission via angle-induced chirality enhancement in split ring resonators
Authors: Bokhari Syed Hussain Ali , Cheema Hammad M.
Published: August 2020

Asymmetric Transmission (AT) allows direction-sensitive control of electromagnetic waves that is highly desirable in optical and microwave communication applications. In this paper, an angle-induced chirality enhancement approach is proposed through the introduction of angled splits in a split ring resonator based unit cell. This design approach, which enhances electromagnetic cross coupling, has been analytically and experimentally validated, yielding efficient and broadband AT operation with 27.1% fractional bandwidth from 14.8 GHz to 19.4 GHz. The AT magnitude of greater than 80% and transmission efficiency of 90% are achieved across the 4.6 GHz bandwidth. These results when compared with recently published designs depict that the presented metasurface exhibits the most broadband AT in a bi-layered configuration with the thinnest reported form factor of 0.78 mm in the microwave regime. The underlying physics of AT operation has been illustrated through analysis of surface currents and electric field distributions. More importantly, new insights into the effects of optical activity on the AT magnitude are presented. The proposed ultra-thin metasurface, operating in K and Ku bands, finds its application as a polarization-control device for modern radar and satellite communication systems.
Ultimate-resolution thermal spectroscopy in time domain thermoreflectance (TDTR)
Authors: Zenji A. , Rampnoux J. M. , Grauby S. , Dilhaire S.
Published: August 2020

Time domain thermoreflectance is a very well-suited technique for thermophysical property measurements. The heterodyne or asynchronous optical sampling versions of the technique allow transient temperature measurements from hundreds of femtoseconds up to tens of nanoseconds. The corresponding spectral material response expands from 100MHz up to 10THz. However, the ultimate bandwidth of the technique is not limited by optical sampling but by the presence of the metal transducer deposited on top of the material of interest. In this work, we investigated the thermal transparency of several metal transducer thin films. We implemented and solved numerically the two-temperature model for a set of Al, Au, Ag, Cu, Cr, and Pt thin (50 and 150 nm) layers. This numerical study showed that Al thin films are better suited for spectroscopic lattice temperature measurements up to 10GHz, while noble metals like Au allow the measurement of hot carrier dynamics up to 5THz.
Evaporation driven detachment of a liquid bridge from a syringe needle in repose
Authors: Ward Thomas
Published: August 2020

In this paper, a study of the stability of an evaporating semi-unbounded axisymmetric liquid bridge that forms between a syringe needle tip and a horizontal interface by using both theory and experiments is presented. Here, the evaporation produces slow quasistatic motion such that it allows one to use hydrostatics to analyze interface profiles via solutions to the Young–Laplace equation. The two main parameters, in the hydrostatic limit, are the familiar Bond number and a slenderness parameter that often appears in the literature that studies liquid bridge stability. The axisymmetric Young–Laplace equation yields a semi-analytical solution for capillary pressure at zero Bond number using boundary conditions appropriate for this study. At finite Bond numbers, computation of interface profiles is used to estimate the maximum slenderness. Experiments using water for Bond numbers 0.01 < Bo < 0.1 show good agreement for the maximum slenderness when comparing those results with predictions based on solutions to the Young–Laplace equation.
Spectroscopic and computational characterization of lanthanide-mediated N–H and C–H bond activation of methylamine
Authors: Nyambo Silver , Zhang Yuchen , Yang Dong-Sheng
Published: August 2020

Ln (Ln = La and Ce) atom reactions with methylamine are carried out in a pulsed-laser vaporization supersonic molecular beam source. A series of dehydrogenation species are observed with time-of-flight mass spectrometry, and the dehydrogenated Ln-containing species in the formula Ln(NCH3) are characterized by mass-analyzed threshold ionization (MATI) spectroscopy and density functional theory and multiconfiguration spin–orbit coupling computations. The MATI spectrum of La(NCH3) consists of two vibronic band systems that are assigned to the ionization of the 2A1 ground state of the C3v isomer La(N–CH3) and the 2A′ ground state of the Cs isomer La(NH–CH2). The MATI spectrum of Ce(NCH3) also displays two band systems, which are attributed to the ionization of the low-energy spin–orbit coupling states of the C3v isomer Ce(N–CH3). Ln(N–CH3) is formed by the concerted dehydrogenation of the amino group, while La(NH–CH2) is formed by the dehydrogenation of both amino and methyl groups. Ce(NH–CH2) is presumably formed in the reaction based on the computational predictions but not observed by the spectroscopic measurements.
Extensive recent wildfires demand more stringent protection of critical old growth forest
Authors: Lindenmayer David , Taylor Chris
Published: August 2020

Old growth forests have many key values, but temporal changes across their spatial extent are poorly understood. This includes large parts of Australia and is a major knowledge gap given the extent of human and natural disturbances in the Australian forest estate over past decades. We integrated spatial data on the timing and extent of fire and logging across mapped forest and woodland cover in different Ecological Vegetation Class (EVC) groups to quantify disturbance of the old growth forest and woodland estate in Victoria since 1995, including after the 2019–20 wildfires. We found ~77% of old growth forest and woodlands have been disturbed by fire and logging over the past 25 years. Disturbance was particularly marked in some EVCs, such as the Wet and Damp Forest and the Subalpine Woodlands. In contrast, relatively little of the Modelled Old Growth Forest and Woodland has been disturbed between 1995 and 2020 in other EVCs such as in Plains Woodlands and Heathy Woodlands. Wildfire was the primary driver of disturbance in Modelled Old Growth Forest and Woodland. We argue that a range of strategies is critical to increase protection of undisturbed old growth forest. These include re-assessing disturbance data layers to ensure that areas of old growth that have been burned at low severity are protected, and reducing the size of old growth patches to be conserved. There is also a need to increase levels of protection of young forests to enable them to grow through to an old growth state.
Abiotic redox reactions in hydrothermal mixing zones: Decreased energy availability for the subsurface biosphere
Authors: McDermott Jill M. , Sylva Sean P. , Ono Shuhei , German Christopher R. , Seewald Jeffrey S.
Published: August 2020

Significance

Hydrothermal fluid geochemistry exerts a key control on subseafloor microbial community structure and function. However, the effects of microbial metabolic activity, thermal decomposition of biomass, and abiotic reactions on geochemistry remain unconstrained. Depletions in molecular hydrogen and enrichments in methane in submarine hydrothermal mixing zones have been interpreted to reflect the influence of an active subseafloor biosphere. In contrast, our work reveals that these chemical shifts are driven by abiotic and thermogenic processes at temperatures beyond the limit for life. These findings have critical implications for constraining the extent to which global geochemical cycles can sustain a deep biosphere, and for the global molecular hydrogen budget.
Mitochondrial [4Fe-4S] protein assembly involves reductive [2Fe-2S] cluster fusion on ISCA1–ISCA2 by electron flow from ferredoxin FDX2
Authors: Weiler Benjamin Dennis , Brück Marie-Christin , Kothe Isabell , Bill Eckhard , Lill Roland , Mühlenhoff Ulrich
Published: August 2020

Significance

Synthesis of iron-sulfur clusters (ISC) and their insertion into apoproteins in eukaryotes requires the conserved, essential mitochondrial ISC and cytosolic Fe/S protein assembly machineries. Genetic mutations in most of the 18 different human ISC genes cause neurological, metabolic, and hematological diseases with often lethal outcome. Here, we have biochemically reconstituted the least-understood part of mitochondrial iron-sulfur protein assembly: The synthesis and insertion of [4Fe-4S] clusters. Apart from the in vivo-identified ISC factors (i.e., the [2Fe-2S] cluster donor GLRX5 and ISCA1–ISCA2–IBA57), this reaction specifically requires reduced ferredoxin FDX2, but not FDX1, for reductive fusion of [2Fe-2S]
2+
into [4Fe-4S]
2+
clusters. In contrast, [2Fe-2S] cluster transfer from GLRX5 to [2Fe-2S] target proteins occurs rapidly without any additional ISC factor.
Origin of the “odd” behavior in the ultraviolet photochemistry of ozone
Authors: Han Shanyu , Gunthardt Carolyn E. , Dawes Richard , Xie Daiqian , North Simon W. , Guo Hua
Published: August 2020

Significance

This study solves a 30-y mystery about the origin of dramatic oscillations in the quantum product states of
16
O
3
upon photodissociation. Ozone is a key component of the atmosphere and undergoes complex cycles of formation and destruction by photodissociation and reaction. These dynamics are a rich proving ground for theories of quantum reaction dynamics as well as subtleties such as nuclear spin-statistics and symmetry. A previous theory constructed to explain the observed oscillations, although plausible, was not fully consistent with experimental measurements. Our quantum model and calculations show conclusively the origin of the effect, and match new more detailed experiments.
Address variation in sociocultural context
Authors: Bresin Agnese
Published: August 2020

This study looks at the sociocultural context of five Italian regions and at the situational context of restaurant encounters (a sub-type of service encounters) to examine address variation in spoken Italian—with a focus on singular address pronouns tu, voi and lei. It offers a thorough examination of distance and power dynamics between waiters and customers in a wide range of restaurant types. This book marks the introduction of Italian to the field of regional pragmatic variation and it will be of interest to linguists, Italianists and researchers more broadly working on service encounters. The author offers a new dimension to the understanding of social interaction and language use in contemporary Italy, uncovering cultural and linguistic differences between even adjacent geographical areas within a modern European nation state.
An examination of geometrical and potential time delays in gravitational lensing
Authors: Tsupko Oleg Yu , Bisnovatyi-Kogan Gennady S , Rogers Adam , Er Xinzhong
Published: August 2020

In this paper we investigate the relation between the potential and geometric time delays in gravitational lensing. In the original paper of Shapiro (1964), it is stated that there is a time delay in the radar signals between Earth and Venus that pass near a massive object (the Sun), compared to the path taken in the absence of any mass. The reason for this delay is connected with the influence of gravity on the coordinate velocity of a light ray in a gravitational potential. The contribution from the change of the path length, which happens to be of second order, is considered as negligible. Nevertheless, in the gravitational lens theory the geometrical delay, related to the change of path length, is routinely taken into account along with the potential term. In this work we explain this apparent discrepancy. We address the contribution of the geometric part of the time delay in different situations, and introduce a unified treatment with two limiting regimes of lensing. One of these limits corresponds to the time delay experiments near the Sun where the geometrical delay is shown to be negligible. The second corresponds to the typical gravitational lens scenario with multiple imaging where the geometrical delay is shown to be significant. We introduce a compact, analytical, and quantitative criteria based on relation between the angular position of source and the Einstein radius. This criterion allows one to find out easily when it is necessary to take the geometrical delay into account. In particular, it is shown that the geometrical delay is non-negligible in the case of good alignment between source, lens and observer, because in such a case it becomes a first order quantity (the same order as the potential term).
Inertial focusing in two dimensional flows with sharp viscosity stratification in a microchannel
Authors: Krishnaveni T , Renganathan T , Pushpavanam S
Published: August 2020

Recent experimental studies have shown that lateral particle migration can be controlled passively using stratified flows of co-flowing streams. In this study, we numerically analyze particle migration in a stratified Poiseuille flow of two liquids of different viscosities. A novel numerical approach using immersed boundary method is employed to perform 2D simulations in moving frame of reference. The effect of viscosity ratio, flowrate ratio, Reynolds number and particle size on focusing position is analyzed to identify conditions under which particle migration occurs from one fluid to the other. It is shown that the particle migrates to the low viscous fluid beyond a critical flowrate ratio which increases with particle size. The results of the present study can be used to select suitable flowrate ratio to enable separation of particles of different sizes in membrane less separators.
Voltage-driven displacement of magnetic vortex cores
Authors: Ghidini M , Pellicelli R , Mansell R , Pesquera D , Nair B , Moya X , Farokhipoor S , Maccherozzi F , Barnes C H W , Cowburn R P , Dhesi S S , Mathur N D
Published: August 2020

Magnetic vortex cores in polycrystalline Ni discs underwent non-volatile displacements due to voltage-driven ferroelectric domain switching in single-crystal BaTiO3. This behaviour was observed using photoemission electron microscopy to image both the ferromagnetism and ferroelectricity, while varying in-plane sample orientation. The resulting vector maps of disc magnetization match well with micromagnetic simulations, which show that the vortex core is translated by the transit of a ferroelectric domain wall, and thus the inhomogeneous strain with which it is associated. The non-volatility is attributed to pinning inside the discs. Voltage-driven displacement of magnetic vortex cores is novel, and opens the way for studying voltage-driven vortex dynamics.
Physical properties of the layered oxypnictide Sr2ScFeAsO3: a Mössbauer study down to 1.7 K
Authors: Idczak R , Bukowski Z , Nguyen T T H , Tran V H
Published: August 2020

A polycrystalline sample of Sr2ScFeAsO3 was studied by 57Fe Mössbauer spectroscopy down to 1.7 K. In contrast to the earlier Mössbauer data, the obtained in this work results indicate that Sr2ScFeAsO3 is in paramagnetic state down to 10 K, while the spectra recorded at 4.6 K and 1.7 K show a weak magnetic order of Fe moments in the Fe2As2 layers. Temperature dependences of isomer shift and quadrupole splitting/shift are compared with specific heat and electrical resistivity data from earlier investigations revealing different local Debye temperatures for the Fe2As2 and perovskite-related Sr2ScO3 layers. Finally, a fast decrease of the carrier density was observed below 80 K and this effect seems to be responsible for the absence of superconductivity in the studied compound.
New type of rotation of chiral mechanical metamaterials
Authors: Dudek K K
Published: August 2020

In this work, it is shown experimentally for the first time that chiral mechanical metamaterials can induce their own global rotational motion, i.e. the rotation of the entire system with respect to its centre of mass, without any external forces acting on it. To better understand this effect, which is very different from other types of deformations studied in the literature and offers an insight into what aspects of dynamic behaviour of mechanical metamaterials are yet to be discovered, a number of different prototypes of chiral systems are analysed where it is shown what type of a design allows to maximise the extent of the exhibited rotation. In addition to this, the theoretical model corresponding to computer simulations utilising the Molecular Dynamics approach is proposed and used to establish the hypothetical limit of the considered phenomenon. It is also discussed what are the parameters that can be used in order to fine-tune the extent of the global rotation exhibited by chiral systems. Finally, it is discussed that the concept studied in this work can be used in numerous applications such as satellites, spacecraft, telescopes employed in space as well as novel robotics to control their global rotational motion.
Highly efficient XUV generation via high-order frequency mixing
Authors: Khokhlova M A , Strelkov V V
Published: August 2020

The efficient generation of the coherent XUV light via frequency conversion of intense laser drivers is a problem of both fundamental and technological importance. Increasing the intensity of the generated high harmonics by raising the intensity of the driving field works only up to a point: at high intensities, rapid ionisation of the medium limits the conversion efficiency. Considering the combined effect of the phase-matching and of the blue shift of the driving field during its propagation in a rapidly ionising medium, we show that the latter can be the dominant limiting mechanism. We introduce a new spatial scale, the blue-shift length, which sets the upper bound for the quadratic intensity growth of the generated harmonics. Moreover, we show that this seemingly fundamental restriction can be overcome by using an additional generating weak mid-IR field. For specific combinations of frequencies of the generating fields, the corresponding high-order frequency-mixing process does not suffer from the blue shift of the drivers and phase mismatch, and thus its efficiency grows quadratically with propagation distance. Our results thus open a new route for highly efficient generation of coherent XUV light.
Probing electroweak dark matter at 14 TeV LHC *
Authors: Xu Shuai , Zheng Si-Bo
Published: August 2020

Well-motivated electroweak dark matter is often hosted by an extended electroweak sector that also contains new lepton pairs with masses near the weak scale. In this study, we explore such electroweak dark matter by combining dark matter direct detection experiments and high-luminosity LHC probes of new lepton pairs. Using Z- and W-associated electroweak processes with two or three lepton final states, we show that depending on the overall coupling constant, dark matter masses of up to 170-210 GeV can be excluded at the

level and those up to

GeV can be discovered at the

level at the 14 TeV LHC with integrated luminosities of 300 fb

and 3000 fb

, respectively.
Radiative decays of f1(1285) as the K*K̅
molecular state *
Authors: Xie Ju-Jun , Li Gang , Liu Xiao-Hai
Published: August 2020

With

as a dynamically generated resonance from

interactions, we estimate the rates of the radiative transitions of the

meson to the vector mesons

,

and

. These radiative decays proceed via the kaon loop diagrams. The calculated results are in a fair agreement with experimental measurements. Some predictions can be tested experimentally; their analysis will be valuable for decoding the strong coupling of the

state to the

channel.
Dark matter search at colliders and neutrino floor *
Authors: Cao Qing-Hong , Wei An-Kang , Xiang Qian-Fei
Published: August 2020

The sensitivity of the direct detection of dark matter (DM) approaches the so-called neutrino floor, below which it is difficult to disentangle the DM candidate from the neutrino background. In this work, we consider the scenario that no DM signals are reported in various DM direct detection experiments and explore whether collider searches could probe DM below the neutrino floor. We adopt several simplified models in which the DM candidate couples to electroweak gauge bosons or leptons in the standard model only through high-dimensional operators. After including the RGE running effect, we investigate the constraints of direct detection, indirect detection, and collider searches. The collider search can probe light DM below the neutrino floor. Particularly, for the effective interaction of

, current data from the mono-photon channel at the 13 TeV LHC has already covered the entire parameter space of the neutrino floor.
Null geodesics, quasinormal modes, and thermodynamic phase transition for charged black holes in asymptotically flat and dS spacetimes *
Authors: Wei Shao-Wen , Liu Yu-Xiao
Published: August 2020

A numerical study has indicated that there exists a relation between the quasinormal modes and the Davies point for a black hole. In this paper, we analytically study this relation for charged Reissner-Nordström black holes in asymptotically flat and de Sitter (dS) spacetimes in the eikonal limit, under which the quasinormal modes can be obtained from the null geodesics using the angular velocity

and the Lyapunov exponent

of the photon sphere. Both in asymptotically flat and dS spacetimes, we observe spiral-like shapes in the complex quasinormal mode plane. However, the starting point of the shapes does not coincide with the Davies point. Nevertheless, we find a new relation in which the Davies point exactly meets the maximum temperature T in the T-

and T-

planes. In a higher-dimensional asymptotically flat spacetime, although there is no spiral-like shape, such a relation still holds. Therefore, we provide a new relation between black hole thermodynamics and dynamics in the eikonal limit. Applying this relation, we can test the thermodynamic property of a black hole using the quasinormal modes.
Modified astrophysical S-factor of 12C+12C fusion reaction at sub-barrier energies *
Authors: Li Y. J. , Fang X. , Bucher B. , Li K. A. , Ru L. H. , Tang X. D.
Published: August 2020

The 12C+12C fusion reaction plays a crucial role in stellar evolution and explosions. Its main open reaction channels include

, p, n, and 8Be. Despite more than a half century of efforts, large differences remain among the experimental data of this reaction measured using various techniques. In this work, we analyze the existing data using a statistical model. Our calculation shows the following: 1) the relative systematic uncertainties of the predicted branching ratios decrease as the predicted ratios increase; 2) the total modified astrophysical S-factors (S
* factors) of the p and

channels can be obtained by summing the S
* factors of their corresponding ground-state transitions and the characteristic

rays, while taking into account the contributions of the missing channels to the latter. After applying corrections based on branching ratios predicted by the statistical model, an agreement is achieved among the different data sets at E
cm> 4 MeV, while some discrepancies remain at lower energies, suggesting the need for better measurements in the near future. We find that theS
* factor recently obtained from an indirect measurement is inconsistent with the direct measurement value at energies below 2.6 MeV. We recommend upper and lower limits for the 12C+12C S
* factor based on the existing models. A new 12C+12C reaction rate is also recommended.
Microwave plasma torch for wound treatment
Authors: Bogdanov T. , Tsonev I. , Traikov L.
Published: August 2020

Cold atmospheric pressure plasma (CAP) sources have recently been proven to be an effective therapeutic source regarding wound healing. The most preferred and used plasma devices at this moment are the well-known dielectric barrier discharges (DBD) and free jet devices. In this work, we studied a low temperature plasma torch at atmospheric pressure sustained by a travelling electromagnetic wave excited by surfatron type wave launcher coupled to solid state microwave generator. This plasma source allows variation of discharge conditions: geometric parameters (discharge tube inner diameter and thickness), wave power and gas flow velocity which varies the main plasma parameters (length, gas temperature, concentration of charged particles and reactive species, UV and microwave radiation). Appropriate combination of the parameters lead to the low temperature plasma torch obtaining a gas temperature up to 30–37°C, suitable for in vivo treatment of BALB-C mouse models. The purpose of this research is to study the discharge conditions leading to acceleration of wound healing at short treatment times with relatively low gas flow and microwave power