bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scaling laws of quasi-periodic pulsations in solar flares
Authors: Pugh C. E. , Broomhall A.-M. , Nakariakov V. M. 
Published: March 2019

Context. Quasi-periodic pulsations (QPPs) are a common feature of solar flares, but there has previously been a lack of observational evidence to support any of the theoretical models that might explain the origin of these QPPs.
Aims. We aimed to determine if there are any relationships between the QPP period and other properties of the flaring region, using a previously assembled sample of flares with QPPs. If any relationships exist, then these can be compared with scaling laws for the theoretical QPP mechanisms.
Methods. To obtain the flaring region properties, we made use of the Atmospheric Imaging Assembly (AIA) 1600 Å and Helioseismic and Magnetic Imager (HMI) data. The flare ribbons are visible in AIA 1600 Å images, and the positive and negative magnetic polarity ribbons can be distinguished and the magnetic properties determined in the HMI magnetograms. The ribbon properties calculated in this study were the ribbon separation distance, area, total unsigned magnetic flux, and average magnetic field strength. Only the flares that occurred within ±60° of the solar disc centre were included, which meant a sample of 20 flares with 22 QPP signals.
Results. Positive correlations were found between the QPP period and the ribbon properties. The strongest correlations were with the separation distance and magnetic flux. Because these ribbon properties also correlate with the flare duration and because the relationship between the QPP period and flare duration may be influenced by observational bias, we also made use of simulated data to determine whether artificial correlations were introduced. These simulations show that although QPPs cannot be detected for certain combinations of QPP period and flare duration, this does not introduce an apparent correlation.
Conclusions. There is evidence of relationships between the QPP period and flare ribbon properties, and in the future, the derived scaling laws between these properties can be compared to equivalent scaling laws for theoretical QPP mechanisms.
First direct detection of an exoplanet by optical interferometry
Authors:   GRAVITY Collaboration, Lacour S. , Nowak M. , Wang J. , Pfuhl O. , Eisenhauer F. , Abuter R. , Amorim A. , Anugu N. , Benisty M. , Berger J. P. , Beust H. , Blind N. , Bonnefoy M. , Bonnet H. , Bourget P. , Brandner W. , Buron A. , Collin C. , Charnay B. , Chapron F. , Clénet Y. , Coudé du Foresto V. , de Zeeuw P. T. , Deen C. , Dembet R. , Dexter J. , Duvert G. , Eckart A. , Förster Schreiber N. M. , Fédou P. , Garcia P. , Garcia Lopez R. , Gao F. , Gendron E. , Genzel R. , Gillessen S. , Gordo P. , Greenbaum A. , Habibi M. , Haubois X. , Haußmann F. , Henning Th. , Hippler S. , Horrobin M. , Hubert Z. , Jimenez Rosales A. , Jocou L. , Kendrew S. , Kervella P. , Kolb J. , Lagrange A.-M. , Lapeyrère V. , Le Bouquin J.-B. , Léna P. , Lippa M. , Lenzen R. , Maire A.-L. , Mollière P. , Ott T. , Paumard T. , Perraut K. , Perrin G. , Pueyo L. , Rabien S. , Ramírez A. , Rau C. , Rodríguez-Coira G. , Rousset G. , Sanchez-Bermudez J. , Scheithauer S. , Schuhler N. , Straub O. , Straubmeier C. , Sturm E. , Tacconi L. J. , Vincent F. , van Dishoeck E. F. , von Fellenberg S. , Wank I. , Waisberg I. , Widmann F. , Wieprecht E. , Wiest M. , Wiezorrek E. , Woillez J. , Yazici S. , Ziegler D. , Zins G. 
Published: March 2019

Aims. To date, infrared interferometry at best achieved contrast ratios of a few times 10−4 on bright targets. GRAVITY, with its dual-field mode, is now capable of high contrast observations, enabling the direct observation of exoplanets. We demonstrate the technique on HR 8799, a young planetary system composed of four known giant exoplanets.
Methods. We used the GRAVITY fringe tracker to lock the fringes on the central star, and integrated off-axis on the HR 8799 e planet situated at 390 mas from the star. Data reduction included post-processing to remove the flux leaking from the central star and to extract the coherent flux of the planet. The inferred K band spectrum of the planet has a spectral resolution of 500. We also derive the astrometric position of the planet relative to the star with a precision on the order of 100 μas.
Results. The GRAVITY astrometric measurement disfavors perfectly coplanar stable orbital solutions. A small adjustment of a few degrees to the orbital inclination of HR 8799 e can resolve the tension, implying that the orbits are close to, but not strictly coplanar. The spectrum, with a signal-to-noise ratio of ≈5 per spectral channel, is compatible with a late-type L brown dwarf. Using Exo-REM synthetic spectra, we derive a temperature of 1150 ± 50 K and a surface gravity of 104.3 ± 0.3 cm s2. This corresponds to a radius of 1.17−0.11+0.13 RJup and a mass of 10−4+7 MJup, which is an independent confirmation of mass estimates from evolutionary models. Our results demonstrate the power of interferometry for the direct detection and spectroscopic study of exoplanets at close angular separations from their stars.
The use of anterior cervical interbody spacer with integrated fixation screws for management of cervical disc disease
Authors: El Baz Ehab Adel , Sultan Ahmed Maher , Barakat Ahmed Samir , Koptan Wael , ElMiligui Yasser , Shaker Hesham 
Published: March 2019

Introduction: Integrated cage and screw designs were introduced for anterior cervical discectomy and fusion (ACDF) and allegedly are superior to anterior plating due to their minimal anterior profile.

Methods: A descriptive study was designed as a prospective case series of 25 patients (30 operated discs) with cervical disc disease treated with a zero-profile cage, and followed up for an average of 16 months (range 12 –18 months). Functional assessment was done with the Neck Disability Index (NDI) and Visual analog scale (VAS) scores for arm and neck pain. Furthermore, Nurick’s classification system for myelopathy based on gait abnormalities was documented. Radiological fusion was confirmed with plain X-rays and when indicated with a CT scan at 12 months postoperatively. Dysphagia was classified according to the Bazaz criteria.

Results: VAS for neck and arm pain, NDI, and Nurick Score immediately improved postoperatively and remained so at 12-month follow-up. Fusion was achieved in 19 patients (95%) at six months and in 20 patients (100%) of the single-level group at one year. At six months 80% (four patients) and at 12 months 100% (five patients) showed complete union in the double-level group.
No evidence of cage subsidence was noted radiographically.

Discussion: The favorable lordosis and fusion rates of the low-profile integrated device are consistent with ACDF using anterior plating. Additionally, improved pain and an acceptable rate of dysphagia support the use of integrated interbody spacers for use in ACDF procedures.
Toe Flexor Muscle Strength and Morphological Characteristics of the Foot in Judo Athletes
Authors: Koyama Keiji , Hirokawa Mitsushi , Yoshitaka Yukiharu , Yamauchi Junichiro 
Published: March 2019

AbstractWhether practicing in judo influences the muscle strength and morphological characteristics of the foot is unknown. The purpose of this study was to determine the toe flexor muscle strength and morphological characteristics of the foot in judo athletes. Judo athletes (JUDO, men=24) and age-, gender- and body mass-matched physically active healthy subjects (CON, men=24) were recruited, and their toe flexor strength and morphological characteristics of the foot were compared. The maximum isometric toe flexor strength and foot intrinsic muscle thicknesses were measured using a toe grip dynamometer and a B-mode ultrasound, respectively. Foot arch height was assessed as the distance between the navicular tuberosity of the foot and the floor in the sitting and standing positions. JUDO showed a significantly lower foot arch height and smaller foot arch index than CON, whereas foot length and muscle thickness did not significantly differ between groups. The toe flexor strength relative to total muscle thickness was significantly larger in JUDO than CON. The foot arch dynamics was significantly larger in JUDO than CON. This study suggests that exercise training specific to judo may affect the force-generating capacity, morphological structure and arch function of the foot.
Ganganalyse und Gangtraining in der orthopädischen Rehabilitation nach Gelenkersatz – zurück zum normalen Gang, aber wie?
Authors: Jöllenbeck Thomas , Pietschmann Juliane 
Published: March 2019

ZusammenfassungGanganalysen sowie Gangtraining stellen in der orthopädischen Rehabilitation wichtige Methoden dar, um nach endoprothetischem Gelenkersatz das Gehen wieder zu erlernen. Mehrere Jahre postoperativ zeigen sich jedoch noch deutliche Defizite im Gangbild. Neueste Trainingsmethoden sollen helfen, die am Ende der Rehabilitation noch defizitären Parameter anzusteuern und das Gehen wieder richtig zu erlernen.
Vergleich eines Widerstandstrainings und sensomotorischen Trainings bei Patienten nach vorderer Kreuzbandplastik auf motorische Parameter und klinische Funktion
Authors: Nitzsche Nico , Jatzwauk Anne , Baumgärtel Lutz , Schulz Henry 
Published: March 2019

ZusammenfassungWiderstandstraining und sensomotorisches Training werden in der medizinischen Trainingstherapie zur Funktionswiederherstellung bei Patienten nach Kreuzbandplastik eingesetzt. Ziel der Studie war es, beide Trainingsinhalte auf die Reduktion des bilateralen Kraftdefizits sowie posturale Stabilität, Laxizität und Beweglichkeit an Patienten während ambulanter Rehabilitation zu vergleichen. 28 Patienten mit vorderer Kreuzbandersatzplastik wurden 2 Trainingsgruppen in der medizinischen Trainingstherapie (5 TE / Woche, je 60 Minuten) zugeordnet (Krafttrainingsgruppe: N = 14; Alter: 34,9 ± 9,1 Jahre; Körpergröße: 1,78 ± 0,1 m; Gewicht: 86,0 ± 11,1 kg, BMI: 27,4 ± 3,8 kg/m²; sensomotorische Trainingsgruppe: N = 14; Alter: 33,7 ± 8,7 Jahre; Körpergröße: 1,80 ± 0,1 m; Gewicht: 80,6 ± 16,6; BMI: 24,9 ± 4,7 kg/m²). Zum Beginn und am Ende des Rehabilitationszeitraums wurden Kraft, posturale Stabilität, Bandlaxizität, Beweglichkeit sowie klinische Scores zur Beurteilung der Funktion erhoben. Die Ergebnisse zeigten in beiden Gruppen signifikante Reduktionen des bilateralen Kraftdefizits der Beinstrecker und- beuger (p < 0,05). Im Star Excursion Balance Test (SEBT) zeigten sich signifikante Verbesserungen (p < 0,05). Die klinischen Funktionsscores zeigten signifikante Zunahmen (p < 0,05). Ebenso konnten eine signifikante Reduktion des Extensionsdefizits und eine Erhöhung der Knieflexion festgestellt werden (p < 0,05). Die posturale Stabilität sowie die Bandlaxizität zeigte keine signifikanten Veränderungen (> 0,05). Der Zwischensubjektfaktor Trainingsgruppe zeigte bei allen untersuchten Parametern keinen signifikanten Effekt (p > 0,05) und rangierte zwischen -0,88 bis 0,54. Es ist festzustellen, dass beide Trainingsinhalte eine vergleichbare Reduktion der Funktionsdefizite bewirken.
Auswirkung der verspäteten Vorstellung von Handinfektionen
beim Handchirurgen – eine retrospektive Single-Center-Studie von 379
Patienten
Authors: Dastagir Khaled , Luketina Rosalia , Kuhbier Joern Wolfgang , Ziegler Andreas , Vogt Peter M. , Könneker Sören 
Published: March 2019

Zusammenfassung
Ziel Diese Studie untersucht, inwieweit der Vorstellungszeitpunkt bei
vorliegender Handinfektion (HI) mit der stationären Liegedauer sowie der
Häufigkeit notwendiger Operationen der Patienten korreliert.
Patienten und Methoden Retrospektiv wurden die stationären Krankenakten
von 379 Patienten mit HI, die zwischen 2007 und 2014 an unserer Klinik
(2007–2014) behandelt wurden, statistisch hinsichtlich eines Zusammenhangs
zwischen Vorstellungszeitpunkt und Liegedauer sowie der Häufigkeit notwendiger
Operationen ausgewertet, wobei auch die Infektionsursache Berücksichtigung
fand.
Ergebnisse Im Durchschnitt führte eine um mehr als einen Tag verzögerte
fachchirurgische Vorstellung zu einer längeren Krankenhausverweildauer von 1,22
Tage (KHVD) (95 %-KI: 1,20–1,25; p < 0,001). Die Notwendigkeit einer
operativen Intervention nahm mit jedem Tag Verzögerung um 13,59 % (95 %-KI 4,01
%–25,43 %; p < 0,001) zu. Der verzögerte Beginn einer Antibiotikagabe führte
zur Verlängerung der KHVD um den Faktor 1,09 (95 %-KI: 1,03–1,15; p < 0,001),
wobei jedoch keine Korrelation bestand zwischen Zeitpunkt der Antibiotikagabe
und der Notwendigkeit zur operativen Revision (ja/nein) (p = 0,11).
Schlussfolgerung Eine verspätete Vorstellung von Patienten mit
Handinfektionen führt zu einer längeren stationären Aufenthaltsdauer sowie zu
einer höheren Anzahl an notwendigen Operationen. Eine frühzeitige Vorstellung
von HI beim Handchirurgen ist wichtig, um komplizierte Krankheitsverläufe und
unnötige Kosten für das Gesundheitssystem zu vermeiden.
SL-Fusion – keine Alternative zur Behandlung der
chronischen skapholunären Dissoziation
Authors: Petersen Wiebke , Medved Fabian , Schaller Hans-Eberhard , Daigeler Adrien , Held Manuel 
Published: March 2019

Zusammenfassung
Einleitung Die Behandlung der chronischen skapholunären Dissoziation (SLD)
ist derzeit nicht einheitlich und stellt nach wie vor eine große Herausforderung
dar. Sowohl die primäre Bandnaht als auch häufig angewandte ligamentäre
Rekonstruktionsverfahren können keine dauerhaft stabile Verbindung zwischen
Kahnbein und Mondbein schaffen. Aus diesem Grund wird in der vorliegenden Studie
die Wertigkeit einer knöchernen Verbindung als eine Therapieoption zur
Behandlung der chronischen SLD evaluiert.
Ziel Ziel dieser retrospektiven Untersuchung war die radiologische und
klinische Evaluation von Patienten mit skapholunärer Fusion bei chronischer
SLD.
Patienten und Methoden 10 Patienten mit skapholunärer (SL-) Fusion mit
Interposition eines kortikospongiösen Beckenkammspans und
Herbert-Schrauben-Osteosynthese bei symptomatischer, chronischer SLD konnten im
Rahmen einer retrospektiven Studie nach durchschnittlich 7,6 Jahren
nachuntersucht werden. Erfasst wurden die Beweglichkeit, die grobe Kraft, die
Schmerzen, der DASH-, Krimmer- und modifizierte Mayo Wrist Score (MMWS) sowie
das radiologische Ergebnis und die Patientenzufriedenheit.
Ergebnisse Eine primäre knöcherne Heilung wurde in 4 der 10 Fälle erzielt.
Bei 2 weiteren Patienten kam es nach einer Revisionsoperation zur knöchern
konsolidierten SL-Fusion, einmal allerdings unter Einbezug des Kapitatums in die
Teilfusion. 2 Patienten entwickelten eine straffe Pseudarthrose. In 2 Fällen
zeigte sich wiederhin eine skapholunäre Dissoziation, was einmal einer
mediokarpalen Teilversteifung, einmal einer Handgelenksdenervation bedurfte.
Alle Patienten wiesen bei der Nachuntersuchung eine radiokarpale Arthrose auf.
Angesichts der radiologischen Ergebnisse waren die klinischen Ergebnisse
befriedigend bis gut. So berichteten 7 Patienten, sie hätten in Ruhe keine
Schmerzen. Beim MMWS wurden 72 (40–95) Punkte, beim Krimmer-Score 78 (55–100)
Punkte und beim DASH-Score 17 (0–60) Punkte erzielt.
Schlussfolgerung Trotz der befriedigenden und guten klinischen Ergebnisse
der SL-Fusion kann man sie angesichts der primären Versagerquote punkto
knöcherner Heilung von 60 % und der Notwendigkeit zu Revisionsoperation von 40 %
nicht zur Behandlung der chronischen SLD empfehlen.
Top-10 Tips for Getting Started with Magnetic Resonance Neurography
Authors: Chalian Majid , Chhabra Avneesh 
Published: March 2019

AbstractMagnetic resonance neurography (MRN), also known as MR neurography, is a dedicated imaging technique for the peripheral nerves, used both in a clinical setting and research. However, like any other new diagnostic processes, there are technical, cost, and patient selection issues to overcome as well as potential imaging pitfalls to recognize before MRN can be adopted efficiently into routine clinical practice. This review focuses on the 10 most important practical tips to get started with MRN with a view to shortening the time needed for radiologists to implement this clinically useful technique into their imaging practices.
A Novel Rat Model for Comprehensive Microvascular Training of End-to-End, End-to-Side, and Side-to-Side Anastomoses
Authors: Yin Xiaoliang , Ye Gengfan , Lu Jun , Wang Lijun , Qi Peng , Wang Haifeng , Wang Junjie , Hu Shen , Yang Ximeng , Chen Kunpeng , Wang Daming 
Published: March 2019

Background End-to-end, end-to-side, and side-to-side microvascular anastomoses are the main types of vascular bypass grafting used in microsurgery and neurosurgery. Currently, there has been no animal model available for practicing all three anastomoses in one operation. The aim of this study was to develop a novel animal model that utilizes the rat abdominal aorta (AA), common iliac arteries (CIAs), and the median sacral artery (MSA) for practicing these three types of anastomosis.
Methods Eight adult Sprague–Dawley rats were anesthetized and then laparotomized. The AA, MSA, and bilateral CIAs were exposed and separated from the surrounding tissues. The length and diameter of each artery were measured. The relatively long segment of the AA without major branches was selected to perform end-to-end anastomosis. One side of the CIAs (or AA) and MSA were used for end-to-side anastomosis. The bilateral CIAs were applied to a side-to-side and another end-to-side anastomosis.
Results Anatomical dissection of the AA, CIAs, and MSA was successfully performed on eight Sprague–Dawley rats; four arterial-to-arterial anastomoses were possible for each animal. The AA trunk between the left renal artery and right iliolumbar arteries was 15.60 ± 0.76 mm in length, 1.59 ± 0.15 mm in diameter, for an end-to-end anastomosis. The left CIA was 1.06 ± 0.08 mm in diameter, for an end-to-side anastomosis with the right CIA. The MSA was 0.78 ± 0.07 mm in diameter, for another end-to-side anastomosis with the right CIA or AA. After finishing end-to-side anastomosis in the proximal part of bilateral CIAs, the distal portion was juxtaposed for an average length of 5.6 ± 0.25 mm, for a side-to-side anastomosis.
Conclusion This model can comprehensively and effectively simulate anastomosis used in revascularization procedures and can provide more opportunities for surgical education, which may lead to more routine use in microvascular anastomosis training.
Length of the Tendon within the Tibial Tunnel Affects Tibial Tunnel Widening following Anatomic Anterior Cruciate Ligament Reconstruction Using a Bone–Patellar Tendon–Bone Graft
Authors: Taketomi Shuji , Inui Hiroshi , Yamagami Ryota , Kawaguchi Kohei , Nakazato Keiu , Kono Kenichi , Kawata Manabu , Nakagawa Takumi , Tanaka Sakae 
Published: March 2019

AbstractThe purpose of this study was to retrospectively investigate the effects of variations in the length of the tendon within the tibial tunnel on tunnel widening (TW) following anatomical anterior cruciate ligament (ACL) reconstruction using a bone–patellar tendon–bone (BTB) graft. In total, 68 patients who underwent isolated ACL reconstructions using BTB grafts were included in this study. The patients were divided into two groups according to the length of the tendon within the tibial tunnel: group S (n = 30; tendon length, < 10 mm) and group L (n = 38; tendon length, ≥ 10 mm). Tunnel aperture area was measured using three-dimensional computed tomography (3D CT) at 1 week and 1 year postoperatively, and tibial TW (%) was calculated. The correlation coefficient between the length of the tendon within the tibial tunnel and tibial TW was also calculated. Clinical assessment was performed 1 year postoperatively, corresponding to the period of CT assessment, which involved the evaluation of the Lysholm's score, measurement of anterior knee stability using a KneeLax3 arthrometer, and the pivot-shift test. A weak positive correlation was observed between the length of the tendon within the tibial tunnel and tibial TW (r = 0.270, p = 0.026). Mean tibial tunnel aperture area increased by 19.3 ± 17.4% and 35.8 ± 25.4% in the groups S and L, respectively. TW in the group L was significantly greater than that in the group S (p = 0.004). No significant difference was observed between the two groups in any clinical outcomes. In conclusion, a longer tendinous portion within the tibial tunnel resulted in a greater tibial TW following anatomical ACL reconstructions using a BTB graft.
Continuous Video-Rate Laser Speckle Imaging for Intra- and Postoperative Cutaneous Perfusion Imaging of Free Flaps
Authors: Rauh Annika , Henn Dominic , Nagel Sarah S. , Bigdeli Amir K. , Kneser Ulrich , Hirche Christoph 
Published: March 2019

Background Success of free tissue transfer depends on standardized intraoperative flap design, microsurgical technique, and postoperative monitoring. We sought to investigate whether laser speckle imaging (LSI) is suitable for optimization of intraoperative flap design and postoperative monitoring of free flaps with skin paddles.
Methods Skin perfusion was assessed with LSI in 27 free flaps after dissection at the donor site, after anastomosis at the recipient site, after inset and on postoperative days (POD) 1, 5, and 10. Skin perfusion of the whole flap (ROI [region of interest]-1) and the area over the pedicle (ROI-2) were compared between patients with and without postoperative complications (POC+ and POC − , respectively). A receiver operating characteristic (ROC) analysis was performed to determine the optimal cutoff for perfusion during LSI-guided microsurgery.
Results In flaps without or only minor POC, intraoperatively measured perfusion over ROI-2 was significantly higher compared with ROI-1, whereas no significant differences were found for flaps with major POC. Perfusion of ROI-1 and 2 intraoperatively and on POD 1 was significantly lower in the POC+ compared with the POC− group (p < 0.05). ROC analysis yielded a threshold of 107 perfusion units (PU) at ROI-2 with an area under the curve (AUC) of > 0.8 for identification of flaps with major POC.
Conclusion LSI is an easy to use, noninvasive technique for identification of malperfused areas in free flaps, thus allowing for intraoperative decision-making on flap dimensions and postoperative monitoring. LSI therefore is a valuable tool for perfusion assessment with a high potential to become an established part of microsurgical practice.
Research governance and the future(s) of research assessment
Authors: Oancea Alis 
Published: March 2019

AbstractThis paper explores recent public debates around research assessment and its future as part of a dynamic landscape of governance discourses and practices, and organisational, professional and disciplinary cultures. Drawing reflectively on data from RAE 2001, RAE 2008 and REF 2014 (reported elsewhere), the paper highlights how recent debates around research assessment echo longer-term changes in research governance. The following changes, and several critiques of their implications, are discussed: shifts in the principles for governing research and the rise of multi-purpose assessment; the spread of performance-based funding and external accountability for research; the use of metrics and indicators in research assessment; the boundary work taking place in defining and classifying units or fields for assessment; the emphasis on research impact as a component of research value; organisational recalibration across the sector; and the specialisation of blended professional practice. These changes are underpinned by persistent tensions around accountability; evaluation; measurement; demarcation; legitimation; agency; and identity in research. Overall, such trends and the discursive shifts that made them possible have challenged established principles of funding and governance and have pushed assessment technologies into a pivot position in the political dynamics of renegotiating the relationships between universities and the state. Jointly, the directions of travel identified in this paper describe a widespread and persistent regime of research governance and policy that has become embedded in institutional and individual practices.