bluuebunny/crossref_metadata_2025_split huggingface dataset:
The influence of infall on the properties of protoplanetary discs
Authors: Schib O. , Mordasini C. , Wenger N. , Marleau G.-D. , Helled R. 
Published: November 2020

Context. The properties of protoplanetary discs determine the conditions for planet formation. In addition, planets can already form during the early stages of infall.
Aims. We constrain physical quantities such as the mass, radius, lifetime, and gravitational stability of protoplanetary discs by studying their evolution from formation to dispersal.
Methods. We perform a population synthesis of protoplanetary discs with a total of 50 000 simulations using a 1D vertically integrated viscous evolution code, studying a parameter space of final stellar mass from 0.05 to 5 M⊙. Each star-and-disc system is set up shortly after the formation of the protostar and fed by infalling material from the parent molecular cloud core. Initial conditions and infall locations are chosen based on the results from a radiation-hydrodynamic population synthesis of circumstellar discs. We also consider a different infall prescription based on a magnetohydrodynamic (MHD) collapse simulation in order to assess the influence of magnetic fields on disc formation. The duration of the infall phase is chosen to produce a stellar mass distribution in agreement with the observationally determined stellar initial mass function.
Results. We find that protoplanetary discs are very massive early in their lives. When averaged over the entire stellar population, the discs have masses of ~0.3 and 0.1 M⊙ for systems based on hydrodynamic or MHD initial conditions, respectively. In systems characterised by a final stellar mass ~1 M⊙, we find disc masses of ~0.7 M⊙ for the “hydro” case and ~0.2 M⊙ for the “MHD” case at the end of the infall phase. Furthermore, the inferred total disc lifetimes are long, ≈5–7 Myr on average. This is despite our choice of a high value of 10−2 for the background viscosity α-parameter. In addition, we find that fragmentation is common in systems that are simulated using hydrodynamic cloud collapse, with more fragments of larger mass formed in more massive systems. In contrast, if disc formation is limited by magnetic fields, fragmentation may be suppressed entirely.
Conclusions. Our work draws a picture quite different from the one often assumed in planet formation studies: protoplanetary discs are more massive and live longer. This means that more mass is available for planet formation. Additionally, when fragmentation occurs, it can affect the disc’s evolution by transporting large amounts of mass radially. We suggest that the early phases in the lives of protoplanetary discs should be included in studies of planet formation. Furthermore, the evolution of the central star, including its accretion history, should be taken into account when comparing theoretical predictions of disc lifetimes with observations.
Spectroscopy of the helium-rich binary ES Ceti reveals accretion via a disc and evidence of eclipses
Authors: Bąkowska K. , Marsh T. R. , Steeghs D. , Nelemans G. , Groot P. J. 
Published: November 2020

Context. Amongst the hydrogen-deficient accreting binaries known as the AM CVn stars are three systems with the shortest known orbital periods: HM Cnc (321 s), V407 Vul (569 s), and ES Cet (620 s). These compact binaries are predicted to be strong sources of persistent gravitational wave radiation. HM Cnc and V407 Vul are undergoing direct impact accretion in which matter transferred from their donor hits the accreting white dwarfs directly. ES Cet has the longest period of the three and is amongst the most luminous AM CVn stars, but it is not known whether it accretes via a disc or direct impact. ES Cet displays strong HeII 4686 line emission, which is sometimes a sign of magnetically controlled accretion. Peculiarly, although around one third of hydrogen accreting white dwarfs show evidence of magnetism, none have been found amongst helium accretors.
Aims. We present the results of Magellan and VLT spectroscopic and spectropolarimetric observing campaigns dedicated to ES Cet with the aim of understanding its accretion structure.
Methods. Based on the data collected, we derived trailed spectra, computed Doppler maps of the emission lines, and looked for circular polarisation and variability.
Results. We find strong variability in our spectra on the 620 s period. The lines show evidence of double-peaked emission, characteristic of an accretion disc, with an additional component associated with the outermost disc, rather than a direct impact, which is broadly consistent with S-wave emission from the gas stream or disc impact region. This confirms beyond any doubt that 620 s is the orbital period of ES Cet. We find no significant circular polarisation (below 0.1%). The trailed spectra show that ES Cet’s outer disc is eclipsed by the mass donor, revealing at the same time that the photometric minimum coincides with the hitherto unrecognised eclipse.
Conclusions. ES Cet shows spectroscopic behaviour consistent with accretion via a disc, and is the shortest orbital-period eclipsing AM CVn star known.
Midline Suboccipital Subtonsillar Approach in Semisitting Position for Resection of Jugular Tubercle Meningioma: 2-Dimensional Operative Video
Authors: Lieber Stefan , Nunez Maximiliano , Tatagiba Marcos 
Published: November 2020

AbstractWe present a case of a large jugular tubercle meningioma that was removed through a midline suboccipital subtonsillar approach in semisitting position. The patient is a 49-year-old woman with chronic, medication-resistant cephalgias but devoid of any subjective focal neurological deficit. On magnetic resonance imaging (MRI), an extra-axial lesion, originating from the left jugular tubercle was discovered. There was significant obliteration of the peripontine cisternal space, and compression of the adjacent pontomedullary junction; the lesion also extended into the left jugular foramen.On physical exam, an absent gag reflex was noted on the left, as well as a moderate deviation of the uvula to the contralateral side (partial Vernet's syndrome).A gross-total resection was achieved, histopathology confirmed a World Health Organization (WHO) grade I angiomatous meningioma with a low-proliferation index. The patient was discharged home 4 days after surgery with intact function of the lower cranial nerves (CN) following immediate and complete resolution of the preexisting partial CNs IX and X deficits. At 2-year follow-up, there was no indication of intradural residual or recurrence.In summary, the midline suboccipital subtonsillar approach is a simple and effective tool with limited morbidity in the armamentarium for the microsurgical management of pathologies residing in the posterior cranial fossa or the craniocervical junction.Major limitations exist for lesions extending above the internal acoustic canal or those of fibrous consistence featuring widespread adhesion to the ventral brainstem or vascular encasement. Provided the necessary anesthesiological precautions and intraoperative procedures the semisitting position is safe and effective.The link to the video can be found at: https://youtu.be/bbVXagwhDCo.
A Simple Method to Avoid Brain Shift during Neuronavigation: Technical Note
Authors: Raso Jair Leopoldo 
Published: November 2020

Abstract
Introduction The precise identification of anatomical structures and lesions in the brain is the main objective of neuronavigation systems. Brain shift, displacement of the brain after opening the cisterns and draining cerebrospinal fluid, is one of the limitations of such systems.
Objective To describe a simple method to avoid brain shift in craniotomies for subcortical lesions.
Method We used the surgical technique hereby described in five patients with subcortical neoplasms. We performed the neuronavigation-guided craniotomies with the conventional technique. After opening the dura and exposing the cortical surface, we placed two or three arachnoid anchoring sutures to the dura mater, close to the edges of the exposed cortical surface. We placed these anchoring sutures under microscopy, using a 6–0 mononylon wire. With this technique, the cortex surface was kept close to the dura mater, minimizing its displacement during the approach to the subcortical lesion. In these five cases we operated, the cortical surface remained close to the dura, anchored by the arachnoid sutures. All the lesions were located with a good correlation between the handpiece tip inserted in the desired brain area and the display on the navigation system.
Conclusion Arachnoid anchoring sutures to the dura mater on the edges of the cortex area exposed by craniotomy constitute a simple method to minimize brain displacement (brain-shift) in craniotomies for subcortical injuries, optimizing the use of the neuronavigation system.
Revising the Indications of Transtemporal Surgical Approaches in the Modern Endoscopic Era of Skull Base Surgery: A Dying Art
Authors: Manogaran Ravi Sankar , Kumar Raj , Mathialagan Arulalan , Mehrotra Anant , Keshri Amit , Singh Neha , Bhuskute Govind S. , Singh Suyash 
Published: November 2020

Abstract
Objectives The aim of the study is to emphasize and explore the possible transtemporal approaches for spectrum of complicated lateral skull base pathologies.
Design Retrospective analysis of complicated lateral skull base pathologies was managed in our institute between January 2017 and December 2019.
Setting The study was conducted in a tertiary care referral center.
Main Outcome Measures The study focused on the selection of approach based on site and extent of the pathology, the surgical nuances for each approach, and the associated complications.
Results A total of 10 different pathologies of the lateral skull base were managed by different transtemporal approaches. The most common complication encountered was facial nerve palsy (43%, n = 6). Other complications included cerebrospinal fluid (CSF) collection (15%, n = 2), cosmetic deformity (24%, n = 4), petrous internal carotid artery injury (7%, n = 1), and hypoglossal nerve palsy (7%, n = 1). The cosmetic deformity included flap necrosis (n = 2) and postoperative bony defects leading to contour defects of the scalp (n = 2).
Conclusion Surgical approach should be tailored based on the individual basis, to obtain adequate exposure and complete excision. Selection of appropriate surgical approach should also be based on the training and preference of the operating surgeon. Whenever necessary, combined surgical approaches facilitating full tumor exposure are recommended so that complete tumor excision is feasible. This requires a multidisciplinary team comprising neurosurgeons, neuro-otologist, neuroanesthetist, and plastic surgeons. The surgeon must know precise microsurgical anatomy to preserve the adjacent nerves and vessels, which is necessary for better surgical outcomes.
Co-Occurrence of Pineal-Region and Pituitary-Stalk Hemangioblastomas in a Patient Presenting with Von Hippel-Lindau Disease – A Case Report
Authors: Isolan Gustavo Rassier , Perondi Gerson Evandro , Dalla-Corte Amauri , Giovanini Allan Fernando , Telles João Paulo Mota , Rabelo Nícollas Nunes , Figueiredo Eberval Gadelha 
Published: November 2020

Abstract
Introduction Hemangioblastomas of the pineal region or pituitary stalk are extremely rare. Only two cases of hemangioblastomas involving the pineal region have been reported, and four involving the pituitary stalk. The purpose of the present manuscript is to describe an unusual case of supposed hemangioblastoma found concomitantly in the pineal region and pituitary stalk of a patient diagnosed with Von Hippel-Lindau (VHL) disease.
Case Report A 35-year-old female patient with a previous diagnosis of VHL complaining of occipital headaches and balance disturbances for three weeks, who previously had a cerebellar hemangioblastoma resected. The visual characteristics of the tumor suggested a friable vascular lesion with a reddish-brown surface, and an incisional biopsy was performed. The tumor consisted of a dense vascular network surrounded by fibrous stroma abundant in reticulin and composed by both fusiform and dispersed xanthomatous cells; the immunohistochemistry was immunopositive for neuron-specific enolase and immunonegative for epithelial membranous antigen. The patient has been monitored closely for 2 years, and the supratentorial masses have not presented any volume alteration.
Conclusion This rare association must be taken into account in patients with VHL disease, or at least be suspected in patients who present a thickening of the pituitary stalk and a pineal-region mass. We believe a biopsy of our asymptomatic patient could have been dangerous due to inherent complications like intraoperative bleeding. We recommend close observation of asymptomatic lesions with MRIs every six months or until the lesions become symptomatic. If the pineal-region tumor does become symptomatic, gross resection via a transcallosal approach would be ideal.
Effect of Scribes on Efficiency in Academic Ophthalmology Practice
Authors: Furst Meredith , Chu Edward , Wannamaker Kendall , Planchard Brian , Pacheco Lisa , Vigil Laura , Ahmed Tarana , Johnson Daniel , Waldman Corey 
Published: November 2020

Abstract
Objective The aim of the study is to determine the effects of scribes on efficiency in an academic ophthalmology practice.
Design This is a quality improvement study conducted by two ophthalmologists at an academic ophthalmology practice at UT Health San Antonio from January 2018 to April 2018. Implementation of scribes in practice was the primary intervention. Session time, patient encounter time, and template time adherence were recorded pre- and post-intervention. A second retrospective arm of the study at the same institution was performed to evaluate long-term effects of scribes on efficiency in ophthalmology practice on session times and patient volume 12 to 18 months after intervention.
Main Outcome Measures Primary study outcomes and measures were the effect of scribes in academic ophthalmology practice on physician efficiency in terms of clinic session time, individual encounter time, and amount of patients seen per session, in addition to time adherence based on type of patient encounter.
Results Eighty-three patients and 17 half-day clinic sessions and 169 patients and 21 half-day clinic sessions were included in the preintervention and post-intervention datasets, respectively. Number of patients per session was approximately 15 and was kept similar pre- and post-intervention (p = 0.45). Mean preintervention session time was 265.0 ± 31.4 minutes, in contrast to 223.4 ± 19.9 minutes after intervention (p < 0.001). Mean preintervention patient encounter time was 15.0 ± 8.3 minutes, while the mean encounter time after intervention was 10.9 ± 7.0 minutes (p < 0.005). In a retrospective analysis of 20 clinic sessions and 438 patients 12 to 18 months after intervention, session time increased to 266.0 ± 22.0 minutes on average, but the average number of patients per session increased to 21.9 ± 2.8 minutes.
Conclusion Utilizing scribes in an ophthalmology practice can increase efficiency, allowing more patients to be seen or allowing time for other activities such as teaching or research.
Speed of Online and Print Peer-Reviewed Ophthalmology Publications and Correlation to Journal Bibliometric Measures
Authors: Nuesi Ronaldo , Lee John Y. , Kuriyan Ajay E. , Sridhar Jayanth 
Published: November 2020

Abstract
Objective This study aimed to explore the relationship between publishing speeds and peer-reviewed journal bibliometric measures in ophthalmology.
Methods Journal Citation Reports and Scopus Database were accessed for identification of journal bibliometric measures in ophthalmology. Twelve randomly selected articles from 2018 for all identified journals were studied. All outcome measures were extracted from the full text of articles and correlated with journal bibliometric measures. Statistical analysis was performed on measured parameters in comparison to a previous study.
Main Outcomes and Measures Journal impact factor, Eigenfactor score, and CiteScore were correlated with time from submission or acceptance of manuscripts to online and print publication. The correlation between study design and publishing speeds was also assessed.
Results A total of 55 journals were included for a total of 657 articles. Online publications were significantly faster than print publications for almost every journal (p < 0.001). Laboratory experimental studies had significantly shorter times from submission to online publication (p = 0.002) and acceptance to online publication (p < 0.001) compared with observational and interventional studies. Journal impact factor was positively correlated to publishing speed from acceptance to online publication (p = 0.034). CiteScore was positively correlated to speed from submission to print publication (p = 0.04), acceptance to print publication (p = 0.013), and acceptance to online publication (p = 0.003). Eigenfactor score was not statistically significant when correlated with any outcome measures.
Conclusion Online publication has increased speed of dissemination of knowledge in the ophthalmology literature. Despite reporting higher numbers of submissions every year, ophthalmology journals with higher bibliometric measures of impact tend to publish peer-reviewed articles faster than journals with lower impact scores. Study design of an article may affect its speed to publication.
Comparison of Semi-Cylindrical Recession Trochleoplasty and Trochlear Block Recession for the Treatment of Canine Medial Patellar Luxation: A Pilot Study
Authors: Blackford-Winders Callie L. , Daubert Michael , Rendahl Aaron K. , Conzemius Michael G. 
Published: November 2020

Abstract
Objective The aim of this study was to describe an alternative method for trochleoplasty, semi-cylindrical recession trochleoplasty (SCRT), and compare it to trochlear block recession (TBR) in regard to recessed trochlear depth, patellar depth, patellar articular contact with the trochlea, recessed trochlear surface area, procedure time, complications and functional outcome.
Study Design Ten dogs with bilateral grade II-III medial patellar luxations underwent bilateral simultaneous correction surgery including tibial tuberosity transposition, lateral imbrication and trochleoplasty with one stifle each undergoing TBR and SCRT. Patients received pre-and postoperative stifle computed tomography scans and pre- and 8-week postoperative pressure platform analysis and physical examinations. Recessed trochlear depth, patellar depth, trochlear surface area, patellar articular contact, procedure time, complications and functional outcomes as measured by gait analysis were compared between the two techniques.
Results There was no significant difference in measured outcome variables between techniques at any time point. At the time of the 8-week reassessment, no patella had reluxated.
Conclusion Short-term follow-up shows similar functional outcomes between both techniques regarding rate of reluxation and limb function. The SCRT was subjectively easier to perform than TBR, particularly in small patients. The SCRT is an acceptable method of trochleoplasty for the treatment of medial patellar luxation in dogs and further studies evaluating long-term outcomes are justified.
Light bending in a two black hole metric
Authors: Alawadi M Alrais , Batic D , Nowakowski M 
Published: November 2020

AbstractWe discuss the propagation of light in theC-metric. We discover that null geodesics admit circular orbits only for a certain family of orbital cones. Explicit analytic formulae are derived for the orbital radius and the corresponding opening angle fixing the cone. Furthermore, we prove that these orbits based on a saddle point in the effective potential are Jacobi unstable. This completes the stability analysis done in previous literature and allows us to probe into the light bending in a two black hole metric. More precisely, by constructing a suitable tetrad in the Newmann–Penrose formalism, we show that light propagation in this geometry is shear-free, irrotational, and a light beam passing by aC-black hole undergoes a focussing process. An exact analytic formula for the compression factorθis derived and discussed. Furthermore, we study the weak and strong gravitational lensing when both the observer and the light ray belong to the aforementioned family of invariant cones. In particular, we obtain formulae allowing to calculate the deflection angle in the weak and strong gravitational lensing regimes.
Mode localized artificial hair sensor with enhanced linearity applied for dual-axis air flow sensing
Authors: Guo Xin , Yang Bo , Li Cheng , Liang Zhuoyue 
Published: November 2020

Abstract
The weakly coupled resonators based on mode localization are promising in emerging signal measurement fields due to the verified relative mechanical sensitivity enhancement and exceptional ambient robustness. In this work, we report a novel mode localized artificial hair sensor for dual-axis air flow sensing. A new full-scale linear output metric based on differential subtraction of reciprocal amplitude ratios (SRAR) is proposed to suppress the strong inherent non-linearity of amplitude ratio-modulated output metric. The theoretical derivation of mechanical sensitivity demonstrates that the differential SRAR output is strictly linear with the square of input air flow velocity. The fabrication process based on standard deep dry silicon on glass is described and an optimized control and measurement system composed of an analog interface circuit and a digital signal processing circuit is designed for experimental performance evaluation. The tested prototype shows an x-axis mechanical sensitivity of 5.417 × 10−2/(m s)−2 with an x-axis cross-axis coupling coefficient of 0.067 and a y-axis sensitivity of 6.212 × 10−2/(m s)−2 with a y-axis cross-axis coupling coefficient of 0.055. The comparative experiment results confirm that compared to frequency-based output and amplitude ratio-based output, the differential SRAR-based output not only promotes the relative mechanical sensitivity and linearity but also exhibits the superior bias stability, which indicates a better common-mode rejection of ambient fluctuations.
Efficient calculation of phase coexistence and phase diagrams: application to a binary phase-field-crystal model
Authors: Holl Max Philipp , Archer Andrew J , Thiele Uwe 
Published: November 2020

Abstract
We show that one can employ well-established numerical continuation methods to efficiently calculate the phase diagram for thermodynamic systems described by a suitable free energy functional. In particular, this involves the determination of lines of phase coexistence related to first order phase transitions and the continuation of triple points. To illustrate the method we apply it to a binary phase-field-crystal model for the crystallisation of a mixture of two types of particles. The resulting phase diagram is determined for one- and two-dimensional domains. In the former case it is compared to the diagram obtained from a one-mode approximation. The various observed liquid and crystalline phases and their stable and metastable coexistence are discussed as well as the temperature-dependence of the phase diagrams. This includes the (dis)appearance of critical points and triple points. We also relate bifurcation diagrams for finite-size systems to the thermodynamics of phase transitions in the infinite-size limit.