bluuebunny/crossref_metadata_2025_split huggingface dataset:
Air-stable 18-electron adducts of Schrock catalysts with tuned stability constants for spontaneous release of the active species
Authors: Gulyás Henrik , Hayano Shigetaka , Madarász Ádám , Pápai Imre , Szabó Márk , Bucsai Ágota , Martin Eddy , Benet-Buchholz Jordi 
Published: May 2021

AbstractSchrock alkylidenes are highly versatile, very active olefin metathesis catalysts, but their pronounced sensitivity to air still hinders their applications. Converting them into more robust but inactive 18-electron adducts was suggested previously to facilitate their handling. Generating the active species from the inactive adducts, however, required a high-temperature Lewis acid treatment and resulted in an insoluble by-product, limiting the practicality of the methodology. Herein, we introduce an approach to circumvent the inconvenient, costly, and environmentally taxing activation process. We show that 18-electron adducts of W- and Mo-based Schrock catalysts with finite stability constants (typically K = 200–15,000 M−1) can readily be prepared and isolated in excellent yields. The adducts display enhanced air-stability in the solid state, and in solution they dissociate spontaneously, hence liberating the active alkylidenes without chemical assistance.
Femtosecond excited-state dynamics in chlorosomal carotenoids of the photosynthetic bacterium Chloroflexus aurantiacus revealed by near infrared pump–probe spectroscopy
Authors: Yakovlev Andrei G. , Taisova Alexandra S. , Fetisova Zoya G. 
Published: May 2021

In Chloroflexus aurantiacus chlorosomes, extremely fast dynamics occurs in the S2 excited state of carotenoids.
The selective alpha7 nicotinic acetylcholine receptor agonist AR-R17779 does not affect ischemia–reperfusion brain injury in mice
Authors: Hammarlund Maria E. , Darsalia Vladimer , Mjörnstedt Filip , Pattanaik Bagmi , Mallard Carina , Rocha-Ferreira Eridan , Patrone Cesare , Johansson Maria E. 
Published: May 2021

Abstract
Inflammation plays a central role in stroke-induced brain injury. The alpha7 nicotinic acetylcholine receptor (α7nAChR) can modulate immune responses in both the periphery and the brain. The aims of the present study were to investigate α7nAChR expression in different brain regions and evaluate the potential effect of the selective α7nAChR agonist AR-R17779 on ischemia–reperfusion brain injury in mice. Droplet digital PCR (ddPCR) was used to evaluate the absolute expression of the gene encoding α7nAChR (Chrna7) in hippocampus, striatum, thalamus and cortex in adult, naïve mice. Mice subjected to transient middle cerebral artery occlusion (tMCAO) or sham surgery were treated with α7nAChR agonist AR-R17779 (12 mg/kg) or saline once daily for 5 days. Infarct size and microglial activation 7 days after tMCAO were analyzed using immunohistochemistry. Chrna7 expression was found in all analyzed brain regions in naïve mice with the highest expression in cortex and hippocampus. At sacrifice, white blood cell count was significantly decreased in AR-R17779 treated mice compared with saline controls in the sham groups, although, no effect was seen in the tMCAO groups. Brain injury and microglial activation were evident 7 days after tMCAO. However, no difference was found between mice treated with saline or AR-R17779. In conclusion, α7nAChR expression varies in different brain regions and, despite a decrease in white blood cells in sham mice receiving AR-R17779, this compound does not affect stroke-induced brain injury.
Enhancing transferability of adversarial examples via rotation‐invariant attacks
Authors: Duan Yexin , Zou Junhua , Zhou Xingyu , Zhang Wu , Zhang Jin , Pan Zhisong 
Published: May 2021

AbstractDeep neural networks are vulnerable to adversarial examples. However, existing attacks exhibit relatively low efficacy in generating transferable adversarial examples. Improved transferability to address this issue is proposed via a rotation‐invariant attack method that maximizes the loss function w.r.t the random rotated image instead of the original input at each iteration, thus mitigating the high correlation between the adversarial examples and the source models and making the adversarial examples more transferable. Extensive experiments show that the proposed method can significantly improve the transferability of the adversarial examples with almost no extra computational cost and can be integrated into various methods. In addition, when this method is easily applied through a plug‐in, the average attack success rate against six robustly trained models increases by 5.4% over the state‐of‐the‐art baseline method, demonstrating its effectiveness and efficiency. The codes used are publicly available at https://github.com/YeXinD/Rotation‐Invariant‐Attack.
Medical image interpretation training with a low‐cost eye tracking and feedback system: A preliminary study
Authors: Quen Mathieson Tan Zui , Mountstephens J. , Teh Yong Guang , Teo J. 
Published: May 2021

AbstractAll medical students must learn to detect tumours in chest X‐ray films. Eye tracking technology may be able to improve the training of this skill, with the potential benefit of saving thousands of lives each year. Eye trackers can record where students actually look in relation to known abnormalities in images, allowing the automated provision of corrective feedback during medical training. Research using dedicated eye tracking units suggests their potential as pedagogical tools but this hardware can be expensive, which prevents their use by medical students. To overcome this financial barrier, this project used eye tracking based on low‐cost webcams to develop a system with the potential to allow all medical students to improve their interpretation skills. In self‐study mode, students can practice and improve based on automated performance feedback in a browser‐based system. Improvements in performance over time can be determined and mistakes can be played back and analysed for correction. Eight medical trainees used the system on a custom dataset of 60 chest X‐ray images and were able to improve their decision times by self‐study alone. The system was also rated highly for its ability to provide valuable objective information during subsequent one‐on‐one instruction sessions.
Hybrid energy management strategy based on dynamic setting and coordinated control for urban rail train with PMSM
Authors: Wang Xin , Luo Yingbing , Zhou Yu , Qin Yuxin , Qin Bin 
Published: May 2021

AbstractDue to the short distance between stations, frequent acceleration and braking for urban rail trains cause voltage fluctuation in the traction network and the regenerative braking energy loss. In this study, a hybrid energy storage system (HESS) was proposed to recover braking energy and stabilize the traction network voltage, where the on‐board ultracapacitors were used to accommodate the rapid exchange of acceleration and braking energy of the permanent magnet traction system while the lithium batteries installed in the bilateral stations provided stable and long‐lasting energy exchange, which can stabilize traction network voltage and be charged at off‐peak night time. In order to realize the energy coordinated control between the permanent magnet traction system and HESS, a real‐time energy management strategy was proposed to dynamically allocate the traction power based on the principle of giving priority to on‐board ultracapacitors while lithium batteries as auxiliary power supply. Moreover, the charging and discharging voltage thresholds of the lithium batteries were dynamically set according to train positions and their charge status. Comparing with the traditional strategies, the RT‐LAB semi‐physical real‐time simulation shows that the proposed strategy can provide more effective energy allocation, and stabilize the voltage fluctuation while maximizing the energy saving.
Day‐ahead and intra‐day wind power forecasting based on feedback error correction
Authors: Gupta Akshita , Kumar Arun , Boopathi Kadhirvel 
Published: May 2021

AbstractThe major hindrance in the development of large‐scale grid integration of wind energy into the power system is the production of intermittent and variable power. A largescale integration requires a forecasting mechanism to support the power system operators while operating the grids. This study forecasts the day‐ahead and intra‐day wind power using the wavelet decomposition, followed by the autoregressive integrated moving average. The forecasting has been attempted on two datasets, actual and error wind power. The forecasting using the wavelet decomposition employs the discrete wavelets consisting of 16 wavelets, grouped into 5 families. The optimum length of the past data used for the model formulation has also been examined for the various scenarios. The forecasting results have been compared based on various performance metrics. The results of the forecasted values have been compared with the reference ARIMA model to see the effectiveness of the proposed wavelet‐ARIMA model. The results indicate that the feedback mechanism used in the error dataset have improved the forecasting efficiency over the use of actual data in both the day‐ahead and intra‐day forecasting. Also, it has been observed that some of the wavelet families outperformed the other families in terms of accuracy and speed.
MOLsphere and pulsations of the Galactic Center’s red supergiant GCIRS 7 from VLTI/GRAVITY
Authors:   GRAVITY Collaboration, Rodríguez-Coira G. , Paumard T. , Perrin G. , Vincent F. , Abuter R. , Amorim A. , Bauböck M. , Berger J. P. , Bonnet H. , Brandner W. , Clénet Y. , de Zeeuw P. T. , Dexter J. , Drescher A. , Eckart A. , Eisenhauer F. , Förster Schreiber N. M. , Gao F. , Garcia P. , Gendron E. , Genzel R. , Gillessen S. , Habibi M. , Haubois X. , Henning T. , Hippler S. , Horrobin M. , Jimenez-Rosales A. , Jochum L. , Jocou L. , Kaufer A. , Kervella P. , Lacour S. , Lapeyrère V. , Le Bouquin J. B. , Léna P. , Nowak M. , Ott T. , Perraut K. , Pfuhl O. , Sanchez-Bermudez J. , Shangguan J. , Scheithauer S. , Stadler J. , Straub O. , Straubmeier C. , Sturm E. , Tacconi L. J. , Shimizu T. , von Fellenberg S. , Waisberg I. , Widmann F. , Wieprecht E. , Wiezorrek E. , Woillez J. , Yazici S. , Zins G. 
Published: May 2021

Context. GCIRS 7, the brightest star in the Galactic central parsec, formed 6 ± 2 Myr ago together with dozens of massive stars in a disk orbiting the central black-hole. It has been argued that GCIRS 7 is a pulsating body, on the basis of photometric variability.
Aims. Our goal is to confirm photospheric pulsations based on interferometric size measurements to better understand how the mass loss from these massive stars enriches the local interstellar medium.
Methods. We present the first medium-resolution (R = 500), K-band spectro-interferometric observations of GCIRS 7, using the GRAVITY instrument with the four auxiliary telescopes of the ESO VLTI. We looked for variations using two epochs, namely 2017 and 2019.
Results. We find GCIRS 7 to be moderately resolved with a uniform-disk photospheric diameter of θUD* = 1.55 ± 0.03 mas (RUD* = 1368 ± 26 R⊙) in the K-band continuum. The narrow-band uniform-disk diameter increases above 2.3 μm, with a clear correlation with the CO band heads in the spectrum. This correlation is aptly modeled by a hot (TL = 2368 ± 37 K), geometrically thin molecular shell with a diameter of θL = 1.74 ± 0.03 mas, as measured in 2017. The shell diameter increased (θL = 1.89 ± 0.03 mas), while its temperature decreased (TL = 2140 ± 42 K) in 2019. In contrast, the photospheric diameter θUD* and the extinction up to the photosphere of GCIRS 7 (AKS = 3.18 ± 0.16) have the same value within uncertainties at the two epochs.
Conclusions. In the context of previous interferometric and photo-spectrometric measurements, the GRAVITY data allow for an interpretation in terms of photospheric pulsations. The photospheric diameter measured in 2017 and 2019 is significantly larger than previously reported using the PIONIER instrument (θ* = 1.076 ± 0.093 mas in 2013 in the H band). The parameters of the photosphere and molecular shell of GCIRS 7 are comparable to those of other red supergiants that have previously been studied using interferometry. The extinction we measured here is lower than previous estimates in the direction of GCIRS 7 but typical for the central parsec region.
Prädiktoren der Legalbewährung nach forensischer Suchtbehandlung – Zweiter Teil einer Übersichtsarbeit zu Erfolgsdeterminanten einer Unterbringung gemäß § 64 StGB
Authors: Querengässer Jan , Baur Alexander 
Published: May 2021

Zusammenfassung
Hintergrund Ehe eine forensische Suchtbehandlung gemäß § 64 StGB gerichtlich angeordnet werden kann, ist eine Erfolgsprognose zu stellen und zu bejahen. Der Suche nach entsprechenden Prädiktoren für eine „hinreichend konkrete“ Erfolgsaussicht widmeten sich in den vergangenen Jahren einige Studien. Dabei stellt die Legalbewährung nach Entlassung das gesetzlich vorgesehene Erfolgskriterium forensischer Suchtbehandlung dar.
Zielsetzung Als zweiter Teil einer zweiteiligen Gesamtschau zu Erfolgsdeterminanten forensischer Suchtbehandlung gibt die vorliegende Arbeit einen Überblick über die aktuelle Befundlage zu Prädiktoren der Legalbewährung nach forensischer Suchtbehandlung und setzt diese in Beziehung zu der Studienlage bezüglich Prädiktoren des Entlassmodus.
Methodik Basierend auf systematischer Literaturrecherche werden dabei die Ergebnisse von acht empirischen Studien aus dem Zeitraum 2002–2019 vertieft aufbereitet und in einer Überblickstabelle dargestellt.
Ergebnisse Trotz im Detail heterogener Befunde weisen einerseits das Vorliegen motivationaler, lebenspraktischer und sozialer Ressourcen, andererseits die deliktische Vorgeschichte und Eigenschaften der aktuellen Delinquenz relativ klare Bezüge zur Legalbewährung nach erfolgter forensischer Suchtbehandlung auf. Zugleich treten bei ausschließlicher Betrachtung der Legalbewährung als einzigem Kriterium der Behandlungsprognose konzeptionelle Unschärfen zutage, da diese dann durch die Kriminalprognose überlagert wird.
Schlussfolgerung Die Grenzen des gegenwärtigen Forschungsstands legen für die Erstellung einer Behandlungsprognose gem. § 64 StGB ein zweischrittiges Vorgehen nahe: zunächst könnte anhand der Prädiktoren des Entlassmodus die Frage geprüft werden, als wie wahrscheinlich ein regulärer Therapieverlauf angesehen werden kann; sodann könnte anhand der Prädiktoren der Legalbewährung geprüft werden, ob auf eine rückfallpräventive Wirkung forensischer Suchtbehandlung geschlossen werden kann. Beide Teile der Übersichtsarbeit können forensisch-psychiatrische Sachverständige daher bei der Stellung einer reliablen Prognose der Behandlungsaussicht unterstützen. Ergänzend sollte überlegt werden, ob die Informationsgrundlage für Sachverständige etwa durch eine probatorische Phase verbessert werden könnte.
Diversity-Oriented Synthesis of Highly Functionalized Alicycles across Dipolar Cycloaddition/Metathesis Reaction
Authors: Kiss Loránd , Benke Zsanett , Nonn Melinda , Remete Attila M. , Fustero Santos 
Published: May 2021

AbstractThis Account gives an insight into the selective functionalization of some readily available commercial cyclodienes across simple chemical transformations into functionalized small-molecular scaffolds. The syntheses involved selective cycloadditions, followed by ring-opening metathesis (ROM) of the resulting azetidin-2-one derivatives or isoxazoline frameworks and selective cross metathesis (CM) by discrimination of the C=C bonds on the alkenylated heterocycles. The CM protocols have been described when investigated under various conditions with the purpose on exploring chemodifferentiation of the olefin bonds and a study on the access of the corresponding functionalized β-lactam or isoxazoline derivatives is presented. Due to the expanding importance of organofluorine chemistry in drug research as well as of the high biological potential of β-lactam derivatives several illustrative examples to the access of some fluorine-containing molecular entities is also presented in this synopsis.1	Introduction2	Ring C=C Bond Functionalization of Some Cycloalkene β-Amino Acid Derivatives across Chlorosulfonyl Isocyanate Cycloaddition3	Ring C=C Bond Functionalization of Some Cycloalkene β-Amino Acid Derivatives across Nitrile Oxide Cycloaddition4	Ring C=C Bond Functionalization of Some Cycloalkene β-Amino Acid Derivatives across Metathesis5	Functionalization of sSome Cyclodienes across Nitrile Oxide Cycloaddition6	Selective Synthesis of Functionalized Alicycles across Ring-Opening Metathesis7	Selective Synthesis of Functionalized Alicycles through Cross Metathesis8	Summary and Outlook9	List of Abbreviations
Traumatic Spinal Cord Disorders: Current Topics and Future Directions
Authors: Huang Kevin T. , Lu Yi 
Published: May 2021

AbstractTraumatic spinal cord injury (tSCI) is a life-changing and potentially overwhelming event. The sudden disruption of the spinal cord's integrity necessitates rapid attention at a specialized medical center, and involves a multilateral collaboration between neurologists, spine surgeons, critical care physicians, and trauma specialists. Even with care under ideal conditions, many tSCI patients have significant disability that persists for the rest of their lives. However, recently, we have seen a proliferation in clinical and translational trials that offer the promise that new treatments may be available soon.
Health Information System's Responses to COVID-19 Pandemic in China: A National Cross-sectional Study
Authors: Ye Jiancheng 
Published: May 2021

Abstract
Objective After the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, Chinese hospitals and health information technology (HIT) vendors collaborated to provide comprehensive information technology support for pandemic prevention and control. This study aims to describe the responses from the health information systems (HIS) to the COVID-19 pandemic and provide empirical evidence in the application of emerging health technologies in China.
Methods This observational descriptive study utilized a nationally representative, cross-sectional survey of hospitals in China (N = 1,014) from 30 provincial administrative regions across the country. Participants include hospital managers, hospital information workers, and health care providers.
Results Among all the responses, the most popular interventions and applications include expert question-and-answer sessions and science popularization (61.74%) in online medical consultation, online appointment registration (58.97%) in online medical service, and remote consultation (75.15%) in telehealth service. A total of 63.71% of the participating hospitals expanded their fever clinics during the pandemic, 15.38% hospitals used new or upgraded mobile ward rounds systems, and 44.68% hospitals applied online self-service systems. Challenges and barriers include protecting network information security (57.00%) since some hospitals experienced cybersecurity incidents. 71.79% participants hope to shorten wait time and optimize the treatment process. Health care workers experienced increased amount of work during the pandemic, while hospital information departments did not experience significant changes in their workload.
Conclusion In the process of fighting against the COVID-19, hospitals have widely used traditional and emerging novel HITs. These technologies have strengthened the capacity of prevention and control of the pandemic and provided comprehensive information technology support while also improving accessibility and efficiency of health care delivery.
Tunable topological Hall effects in noncollinear antiferromagnet Mn3Sn/Pt bilayers
Authors: Cheng Yang , Yu Sisheng , Zhu Menglin , Hwang Jinwoo , Yang Fengyuan 
Published: May 2021

Noncollinear antiferromagnet Mn3Sn has attracted wide interest as it is a candidate for Weyl semimetal. Here, we report the observation of topological Hall like signals in Mn3Sn/Pt bilayers grown on Al2O3(0001). X-ray diffraction and scanning transmission electron microscopy results confirm the high epitaxial quality of the c-axis-oriented Mn3Sn films. The detected topological Hall resistivity shows a broad temperature range from 210 to 365 K by tuning the thickness of Mn3Sn from 3 to 15 nm. Compared with previously reported topological Hall effects in Mn3Sn at temperatures below 50 K, the observed high-temperature topological Hall signal is likely due to the stabilization of topological spin textures enabled by the strong spin–orbit coupling of the Pt overlayer and the Dzyaloshinskii–Moriya interaction at the Mn3Sn/Pt interface.
Enhanced pyroelectric response at morphotropic and field-induced phase transitions in ferroelectric hafnium oxide thin films
Authors: Mart Clemens , Kämpfe Thomas , Kühnel Kati , Czernohorsky Malte , Kolodinski Sabine , Wiatr Maciej , Weinreich Wenke , Eng Lukas M. 
Published: May 2021

The hafnium oxide material class is characterized by the coexistence of several polymorphs between which phase transitions are induced by means of composition and external electric fields. Pyroelectric materials, which convert heat into electrical energy, exhibit the largest response at such morphotropic or field-induced phase transitions. The hafnium oxide material system is of special interest for pyroelectric applications since it allows for scalable and semiconductor-compatible fabrication. Here, we report large pyroelectric coefficients at the morphotropic transition from the ferroelectric orthorhombic to the centrosymmetric tetragonal phase. The electric field-induced transition between these two phases in doped HfO2 is found to yield large pyroelectric coefficients of up to −142 µCm−2 K−1, a value that is 20 times larger compared to AlN.
Deposition of silver on the surface of microparticles of zirconium and molybdenum oxides during their synthesis by laser ablation in liquid
Authors: Malikov M.M. , Val’yano G.E. , Borodina T.I. 
Published: May 2021

Abstract
The deposition of silver on the surfaces of micro- and nanoparticles of zirconium, molybdenum, and their oxides, obtained by laser ablation of pure metals in aqueous solutions of silver nitrate, is investigated experimentally. Different irradiation regimes and reagent concentrations are approved. The experimental results indicate a possibility of continuous or partial coating (decorating) with silver the surfaces of nanostructures of oxides of the aforementioned metals; using such systems as substrates, one can increase the Raman scattering amplitude. Silver-coated zirconium and molybdenum oxides can be applied in the diagnostic techniques based on the phenomenon of surface-enhanced Raman scattering.
X-ray production and charged-particle acceleration in the irradiation of micro- and nanorod arrays by high-power femtosecond laser pulses
Authors: Ivanov K.A. , Mordvintsev I.M. , Kargina Yu.V. , Shulyapov S.A. , Tsymbalov I.N. , Bozhev I.V. , Volkov R.V. , Timoshenko V.Yu. , Savel’ev A.B. 
Published: May 2021

Abstract
The effect of the size of the rods at the structured silicon target surface on the parameters of the plasma produced when the target is exposed to a high-contrast femtosecond laser pulse with an intensity of 2 × 1018 W cm−2 is investigated. It is shown that irradiation of a target with subwavelength rods (∼ 100 nm in diameter) provides a significant (up to 250 keV) increase in the temperature of hot plasma electrons and their number in comparison with those obtained in the case of a plane target. It was found that in this case the yield of hard X-ray radiation increases several-fold. The observed effect can be attributed to increased absorption and particle motion in a complex field near plasma nonuniformities. It is shown that the presence of rods with a characteristic size of ∼ 1 μm promotes an increase in the production efficiency of multiply charged silicon ions. The result obtained is apparently associated with the radiation penetration between the rods and with collisional ionisation of particles as they fly into vacuum from deeper target layers.