bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eigenspectra of solar active region long-period oscillations
Authors: Dumbadze G. , Shergelashvili B. M. , Poedts S. , Zaqarashvili T. V. , Khodachenko M. , De Causmaecker P. 
Published: July 2021

Context. We studied the low-frequency ≲0.5 h−1 (long-period ≳2 h) oscillations of active regions (ARs). The investigation is based on an analysis of a time series built from Solar Dynamics Observatory/Helioseismic and Magnetic Imager photospheric magnetograms and comprises case studies of several types of AR structures.
Aims. The main goals are to investigate whether ARs can be engaged in long-period oscillations as unified oscillatory entities and, if so, to determine the spectral pattern of such oscillations.
Methods. Time series of characteristic parameters of the ARs, such as, the total area, total unsigned radial magnetic flux, and tilt angle, were measured and recorded using the image moment method. The power spectra were built out of Gaussian-apodised and zero-padded datasets.
Results. There are long-period oscillations ranging from 2 to 20 h, similarly to the characteristic lifetimes of super-granulation, determined from the datasets of the AR total area and radial magnetic flux, respectively. However, no periodicity in tilt angle data was found.
Conclusions. Whatever nature these oscillations have, they must be energetically supported by convective motions beneath the solar surface. The possible interpretations can be related to different types of magnetohydrodynamic oscillations of the multi-scale structure of the AR magnetic field, which is probably linked with the characteristic turnover timescales of the super-granulation cells. The presence of oscillations in the radial magnetic flux data may be connected to periodic flux emergence or cancellation processes.
Implications of the lowest frequency detection of the persistent counterpart of FRB121102
Authors: Resmi L. , Vink J. , Ishwara-Chandra C. H. 
Published: July 2021

Context. The repeating FRB121102 is so far the only extragalactic fast radio burst found to be associated with a counterpart, that is to say a steady radio source with a nearly flat spectral energy distribution (SED) in centimeter wavelengths.
Aims. Previous observations of the persistent source down to 1.6 GHz have not provided a sign of a spectral turnover. Absorption is expected to eventually cause a turnover at lower frequencies. Better constraints on the physical parameters of the emitting medium can be derived by detecting the self-absorption frequency.
Methods. We used the Giant Metre-Wave Radio Telescope during the period of July to December 2017 to observe the source at low radio frequencies down to 400 MHz.
Results. The spectral energy distribution of the source remains optically thin even at 400 MHz, with a spectral index of ν−(0.07 ± 0.03), which is similar to what is seen in Galactic plerions. Using a generic synchrotron radiation model, we obtain constraints on properties of the nonthermal plasma and the central engine powering it.
Conclusions. We present low frequency detections of the persistent source associated with FRB121102. Its characteristic flat SED extends down to 400 MHz. Similar to models for Galactic plerions, we assume that the energy in the persistent source is carried predominantly by leptons. The emitting plasma has a B < 0.01 G, and its age is >524(B/0.01 G)−3/2 yr. We show that the energetics of the persistent source requires an initial spin period shorter than 36 ms, and the magnetic field of the neutron star must exceed 4.5 × 1012 G. This implies that the persistent source does not necessarily require energetic input from a magnetar.
A shock near the virial radius of the Perseus Cluster
Authors: Zhu Z. , Simionescu A. , Akamatsu H. , Zhang X. , Kaastra J. S. , de Plaa J. , Urban O. , Allen S. W. , Werner N. 
Published: July 2021

Context. Previous X-ray studies of the Perseus Cluster, consisting of 85 Suzaku pointings along eight azimuthal directions, revealed a particularly steep decrease in the projected temperature profile near the virial radius (∼r200) towards the northwest (NW).
Aims. To further explore this shock candidate, another 4 Suzaku observations on the NW edge of the Perseus Cluster have been obtained. These deeper data were designed to provide the best possible control of systematic uncertainties in the spectral analysis.
Methods. Using the combined Suzaku observations, we have carefully investigated this interesting region by analyzing the spectra of various annuli and extracting projected thermodynamic profiles.
Results. We find that the projected temperature profile shows a break near r200, indicating a shock with ℳ = 1.9 ± 0.3. Corresponding discontinuities are also found in the projected emission measure and the density profiles at the same location. This evidence of a shock front so far away from the cluster center is unprecedented, and may provide a first insight into the properties of large-scale virial shocks which shape the process of galaxy cluster growth.
Multi-spacecraft study of the solar wind at solar minimum: Dependence on latitude and transient outflows
Authors: Laker R. , Horbury T. S. , Bale S. D. , Matteini L. , Woolley T. , Woodham L. D. , Stawarz J. E. , Davies E. E. , Eastwood J. P. , Owens M. J. , O’Brien H. , Evans V. , Angelini V. , Richter I. , Heyner D. , Owen C. J. , Louarn P. , Fedorov A. 
Published: July 2021

Context. The recent launches of Parker Solar Probe, Solar Orbiter (SO), and BepiColombo, along with several older spacecraft, have provided the opportunity to study the solar wind at multiple latitudes and distances from the Sun simultaneously.
Aims. We take advantage of this unique spacecraft constellation, along with low solar activity across two solar rotations between May and July 2020, to investigate how the solar wind structure, including the heliospheric current sheet (HCS), varies with latitude.
Methods. We visualise the sector structure of the inner heliosphere by ballistically mapping the polarity and solar wind speed from several spacecraft onto the Sun’s source surface. We then assess the HCS morphology and orientation with the in situ data and compare this with a predicted HCS shape.
Results. We resolve ripples in the HCS on scales of a few degrees in longitude and latitude, finding that the local orientations of sector boundaries were broadly consistent with the shape of the HCS but were steepened with respect to a modelled HCS at the Sun. We investigate how several CIRs varied with latitude, finding evidence for the compression region affecting slow solar wind outside the latitude extent of the faster stream. We also identified several transient structures associated with HCS crossings and speculate that one such transient may have disrupted the local HCS orientation up to five days after its passage.
Conclusions. We have shown that the solar wind structure varies significantly with latitude, with this constellation providing context for solar wind measurements that would not be possible with a single spacecraft. These measurements provide an accurate representation of the solar wind within ±10° latitude, which could be used as a more rigorous constraint on solar wind models and space weather predictions. In the future, this range of latitudes will increase as SO’s orbit becomes more inclined.
Tracing satellite planes in the Sculptor group
Authors: Martínez-Delgado David , Makarov Dmitry , Javanmardi Behnam , Pawlowski Marcel S. , Makarova Lidia , Donatiello Giuseppe , Lang Dustin , Román Javier , Vivas Kathy , Carballo-Bello Julio A. 
Published: July 2021

Context.In recent years, a new generation of large-scale imaging surveys have probed wide field regions for the first time around some nearby galaxies in an unprecedentedly low surface-brightness regime (∼28.0−29.0 mag arcsec−2). This provides the chance to discover very faint dwarf satellites by means of systematic visual inspection of these public deep images.Aims.In this paper, we report the first results of a systematic survey of faint dwarf spheroidal galaxies in the vicinity of the bright late-type spiral galaxy NGC 253 by means of a visual inspection of the images taken by the Dark Energy Survey.Methods.We performed a new NGC 253 satellite search using co-added image cutouts reprocessed in the DESI Legacy image surveys. We usedGALFITsoftware to investigate the photometric and structural properties of three dwarf galaxies.Results.We report the discovery of three new dwarf galaxies in the vicinity of the brightest member of the Sculptor filament, the late-type spiral NGC 253, located at a distance of 3.7 Mpc towards Anti-Virgo. We name them Do II, Do III, and Do IV. Assuming they are companions of NGC 253, their total absoluteV-magnitudes fall in the −7 to −9 mag range, which is typical for dwarf satellites in the local Universe. The central surface brightness tends to be extremely low for all three discovered dwarfs and falls roughly in the range of 25−26 mag arcsec−2ing-band. Using known data on distances and velocities of galaxies, we estimate the total virial mass of the NGC 253 group to be 8 × 1011 M⊙, which gives a virial radius ofR200 = 186 kpc and a turn-around radius of 706 kpc. We also discuss the possible existence of a spatially flattened and velocity-correlated satellite system around NGC 253. This large-scale structure is orientated almost edge-on to the line of sight. The possible plane of satellites is only 31 kpc thick with a minor-to-major axis ratio of 0.14. Four out of five galaxies with measured velocities follow a common velocity trend similar to those observed in the planes of satellites around the Andromeda and Centaurus A galaxies. However, the small number of galaxies with known velocities prevents us from reaching a definitive conclusion about the formation scenario of the structure and its possible relation to the surrounding cosmic web.
Malaria in Guinean Rural Areas: Prevalence, Management, and Ethnotherapeutic Investigations in Dionfo, Sub-Prefecture of Labe
Authors: Baldé Aliou Mamadou , Balde Alpha Oumar , Bah Bilo , Barry Halimatou , Traore Saidou , Bah Fatoumata , Balde Mamadou Aliou , Camara Aissata , Traore Mohamed Sahar , Balde Elhadj Saidou , Sylla Ibrahima Kalil , Diallo Sadou 
Published: July 2021

AbstractAs part of a validation program of antimalarial traditional recipes, an ethnotherapeutic approach was applied in Dionfo, a meso-endemic Guinean rural area where conventional health facilities are insufficient. A prevalence investigation indicated a malarial burden of 4.26%. Ethnomedical and ethnobotanical surveys led to a collection of 63 plant species used against malaria from which Terminalia albida (Combretaceae) was one of the most cited. Ethnotherapeutic evaluation of a remedy based on T. albida was applied to 9 voluntary patients suffering from uncomplicated malaria. Treatment of 7 to 14 days led to an improvement of clinical symptoms and a complete parasite clearance achievement of 8/9 patients without side effects. In addition to antiplasmodial activity in vitro and in vivo previously described, this study indicates an efficacy to support the antimalarial traditional use of T. albida, which could constitute a first-aid treatment
when access to other medicines is delayed in the Dionfo community. Ethnotherapeutical investigation could be a valuable approach to guide subsequent investigations on traditional remedies.
Auswirkungen des Lockdowns im Frühjahr 2020 während der COVID-19-Pandemie auf das Ess- und Sportverhalten – Ergebnisse einer Onlinebefragung
Authors: Koopmann Anne , Müller Astrid , Lemenager Tagrid , Hillemacher Thomas , Kiefer Falk , Georgiadou Ekaterini 
Published: July 2021

Zusammenfassung
Einleitung Die Ausgangseinschränkungen und Kontaktverbote während der COVID-19-Pandemie haben mit dem Wegfall vieler beruflicher und privater Verpflichtungen und Strukturen massive Auswirkungen auf den Alltag der Allgemeinbevölkerung. Gleichzeitig verstärken sich für viele Menschen die Sorgen vor allem bezüglich ihrer finanziellen und beruflichen Zukunft. Eine vermehrte Nahrungsaufnahme stellt in dieser Situation eine mögliche Bewältigungsstrategie im Umgang mit den als unangenehm erlebten Gefühlen dar. Gleichzeitig fallen wegen der Ausgangs- und Kontaktbeschränkungen viele Möglichkeiten zur sportlichen Betätigung weg. Dies birgt die Gefahr einer Zunahme der kardiovaskulären Risikofaktoren in der Allgemeinbevölkerung und insbesondere für die Entstehung von Adipositas sowie Diabetes mellitus Typ 2. In dieser Studie untersuchten wir daher die Veränderungen des Ess- und Sportverhaltens in der Allgemeinbevölkerung in Deutschland während des Lockdowns im Frühjahr 2020.
Material und Methodik An der Onlinebefragung zu Veränderungen des Ess- und Sportverhaltens während des Lockdowns im Frühjahr 2020 konnten Frauen und Männer zwischen 18 und 80 Jahren aus der Allgemeinbevölkerung teilnehmen. Die Umfrage war online verfügbar zwischen dem 8. April und dem 11. Mai 2020.
Ergebnisse Von 3259 Teilnehmern gaben 40,3 % an, während des Lockdowns mehr als vor dessen Beginn gegessen zu haben, 38,3 % berichteten, während des Lockdowns weniger Sport gemacht zu haben als in der Zeit davor. Bei einer kombinierten Betrachtung der Verhaltensänderungen zeigten 58,5 % der Teilnehmer mindestens eine Verhaltensänderung, die dauerhaft potenziell negative gesundheitliche Folgen für sie haben könnte und die Entwicklung eines Diabetes mellitus Typ 2 fördert. Mit 18,5 % aller Studienteilnehmer gab die größte Gruppe an, weniger Sport gemacht und gleichzeitig mehr gegessen zu haben während des Lockdowns.
Schlussfolgerungen Diese Ergebnisse weisen darauf hin, dass es sowohl in der ambulanten als auch in der stationären Patientenversorgung in den nächsten Monaten wichtig sein wird, die Patienten auf die Gesundheitsrisiken, die sich durch eine Reduktion von sportlicher Aktivität und eine vermehrte Nahrungsaufnahme ergeben, hinzuweisen und ihr Ess- und Sportverhalten sowie die Veränderung des Körpergewichts zu beobachten, um eine Zunahme des Risikos für Diabetes mellitus Typ 2 in der Allgemeinbevölkerung zu verhindern.
Ag(I)/CAAA-Amidphos Complex Catalyzed Asymmetric 1,3-Dipolar Cycloaddition of Acrylates for the Formal Synthesis of (+)-Ibophyllidine
Authors: Gong Chuliang , Zhang Chen , Zhou Guiyin , Chen Yao , Wang Haifei , Zheng Xiaojun , Hou Qinglin , Zhou Qingxia 
Published: July 2021

AbstractIn this work, we introduced a multifunctional Ag(I)/CAAA-amidphos complex catalyzed asymmetric 1,3-dipolar cycloaddition of acrylates with α-imino esters, affording a series of 2,4,5-trisubstituted endo-pyrrolidines in good yields (up to 97%) with high enantioselectivities (up to 98% ee). Meanwhile, the catalytic system was also applied in the three-component one-pot reaction of α-imino esters formed in situ under the action of N,N′-diisopropylcarbodiimide. In addition, the gram-scale reaction was realized for the formal synthesis of (+)-ibophyllidine in eight steps.
Facilitating Genetics Aware Clinical Decision Support: Putting the eMERGE Infrastructure into Practice
Authors: Taylor Casey Overby , Rasmussen Luke V. , Rasmussen-Torvik Laura J. , Prows Cynthia A. , Dorr David A. , Samal Lipika , Aronson Samuel 
Published: July 2021

AbstractThis editorial provides context for a series of published case reports in ACI Open by summarizing activities and outputs of joint electronic health record integration and pharmacogenomics workgroups in the NIH-funded electronic Medical Records and Genomics (eMERGE) Network. A case report is a useful tool to describe the range of capabilities that an IT infrastructure or a particular technology must support. The activities we describe have informed infrastructure requirements used during eMERGE phase III, provided a venue to share experiences and ask questions among other eMERGE sites, summarized potential hazards that might be encountered for specific clinical decision support (CDS) implementation scenarios, and provided a simple framework that captured progress toward implementing CDS at eMERGE sites in a consistent format.
Nitrofurantoin Susceptibility Pattern in Gram-Negative Urinary Isolates: In Need of Increased Vigilance
Authors: Gautam Garima , Gogoi Sanjib , Saxena Sonal , Kaur Ravinder , Dhakad Megh Singh 
Published: July 2021

AbstractNitrofurantoin is the first-line drug in the treatment of uncomplicated urinary tract infections (UTIs) and its use has increased exponentially in recent years.
Objectives This study aims to determine the susceptibility pattern of nitrofurantoin in gram-negative urinary isolates and to evaluate their bacteriological and epidemiological profile along with co-existing resistance to other important urinary antimicrobials.
Material and Methods This was a retrospective study conducted in a tertiary care hospital in New Delhi in which 500 gram-negative bacterial urinary isolates were evaluated. Records of antimicrobial susceptibility were reviewed from July to September 2019. Antimicrobial susceptibility was performed using the Kirby–Bauer disk diffusion method on Mueller Hinton agar and interpreted using CLSI 2019. Test for extended spectrum β-lactamase (ESBL) producers was done using double disk approximation test.
Statistical Analysis Data analysis was performed using the SPSS windows version 25.0 software.
Results Out of total 500 isolates, 20.17% (94) isolates were resistant (R) to nitrofurantoin and 9.01% (42) were found to be intermediate (I). Highest resistance was seen in Klebsiella sp. (44.61%) and Escherichia coli (8.12%). About 28.82% of the I/R isolates were of the pediatrics age group and most of the isolates belonged to females (64.69%). High resistance was also seen against ampicillin (92.30%), cefazolin (88.46%), ceftazidime (73.0%), and fluoroquinolones (65.38%). Carbapenemase co-resistance was seen in 57.15% isolates whereas ESBL production was seen in 30.76% of E. coli and 12.06% of Klebsiella sp.
Conclusion Increase in multidrug resistance uropathogens along with a near absence of novel oral antibiotics has led to increased consumption of nitrofurantoin since its resistance has increased.
Embedded gas sensing setup for air samples analysis
Authors: Kwiatkowski Andrzej , Drozdowska Katarzyna , Smulko Janusz 
Published: July 2021

This paper describes a measurement setup (eNose) designed to analyze air samples containing various volatile organic compounds (VOCs). The setup utilizes a set of resistive gas sensors of divergent gas selectivity and sensitivity. Some of the applied sensors are commercially available and were proposed recently to reduce their consumed energy. The sensors detect various VOCs at sensitivities determined by metal oxide sensors’ technology and operating conditions. The setup can utilize prototype gas sensors, made of resistive layers of different compositions, as well. Their properties can be modulated by selecting operating temperature or using UV light irradiation. The unit is controlled by an embedded system M5Stack Core2 ESP32 IoT. We used this development kit to program the measurement procedure and data recording fastly. The setup utilizes an aluminum gas chamber of a volume of 220 ml, a set of electrical valves to introduce there an air sample with the help of an electrical micropump. The handling of the setup was simplified to a selection of a few operations by touch screen only without a necessity of extra training. The recorded data are saved in a memory card for further processing. The evolved setup can be upgraded to apply more advanced data processing by utilizing WiFi or Bluetooth connection. The control program was prepared using the Arduino IDE software environment and can be further advanced with ease. The applied materials and the established measurement procedure can use various air samples, including exhaled breath samples for patients’ screening check-ups. We applied the same time of 10 min for response and recovery, acceptable for practical use.
Explicitly correlated Fock-space coupled-cluster singles and doubles method for (1,1), (0,2), and (2,0) sectors
Authors: Bokhan Denis , Bednyakov Alexander S. , Musiał Monika , Perera Ajith , Trubnikov Dmitrii N. 
Published: July 2021

A linearly approximated explicitly correlated coupled-cluster singles and doubles model for the Fock-space coupled-cluster method has been formulated and implemented. An extension of the Fock-space wave operators is introduced in order to treat the short-range correlation effects for excited and doubly electron-attached states. We show that an effective reduction in the number of active virtuals can also be obtained by improving how the short-range correlation is treated. Numerical results to gauge the performance for valence and Rydberg excitation energies, double ionization potentials, and double electron attachment energies of several molecules are obtained. Statistical measures of the errors in excitation energies show that the explicitly correlated results are within 0.1 eV from the complete basis set limit already at the double-ζ level unless the excitation energies are too close to the ionization thresholds. Similar accuracy is seen for the double ionization potentials and double electron attachment energies.
Long-term switching of single photochromic triads based on dithienylcyclopentene and fluorophores at cryogenic temperatures
Authors: Maier Johannes , Weller Tina , Thelakkat Mukundan , Köhler Jürgen 
Published: July 2021

Photochromic molecules can be reversibly converted between two bistable forms by light. These systems have been intensively studied for applications as molecular memories, sensing devices, or super-resolution optical microscopy. Here, we study the long-term switching behavior of single photochromic triads under oxygen-free conditions at 10 K. The triads consist of a photochromic unit that is covalently linked to two strong fluorophores that were employed for monitoring the light-induced conversions of the switch via changes in the fluorescence intensity from the fluorophores. As dyes we use either perylene bisimide or boron-dipyrromethen, and as photochromic switch we use dithienylcyclopentene (DCP). Both types of triads showed high fatigue resistance allowing for up to 6000 switching cycles of a single triad corresponding to time durations in the order of 80 min without deterioration. Long-term analysis of the switching cycles reveals that the probability that an intensity change in the emission from the dyes can be assigned to an externally stimulated conversion of the DCP (rather than to stochastic blinking of the dye molecules) amounts to 0.7 ± 0.1 for both types of triads. This number is far too low for optical data storage using single triads and implications concerning the miniaturization of optical memories based on such systems will be discussed. Yet, together with the high fatigue resistance, this number is encouraging for applications in super-resolution optical microscopy on frozen biological samples.