bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lidar Observations of Instability and Estimates of Vertical Eddy Diffusivity Induced by Gravity Wave Breaking in the Arctic Mesosphere
Authors: Li Jintai , Collins Richard , Lu Xian , Williams Bifford 
Published: December 2020

AbstractOn the night of 18–19 October 2018, sodium resonance lidar measurements show the presence of overturning in the mesospheric sodium layer. Two independent tracers, sodium mixing ratio and potential temperature, derived from resonance and Rayleigh lidar measurements, reveal that vertical spreading of the sodium mixing ratio contours and a layer of convective instability coincide with this overturning. Analysis of lidar measurements also reveals the presence of gravity waves that propagate upward, are saturated, and dissipate at the height of the convective instability. The vertical spreading is analyzed in terms of turbulent diffusive transport using a model based on material continuity of sodium. Estimates of the turbulent eddy diffusion coefficient, K, and energy dissipation rate, ε are derived from the transport model. The energy dissipated by the gravity waves is also calculated and found to be sufficient to generate the turbulence. We consider three other examples of overturning, instability and spreading on the nights of: 17–18 February 2009, 25–26 January 2015, and 8–9 October 2018. For all four events we find that the values of K (∼1,000 m2/s) are larger and the values of ε (∼10–100 mW/kg) are of similar magnitude to those values typically reported by ionization gauge measurements. These examples also reveal that higher levels of turbulent mixing are consistently found in regions of lower stability.
Daytime Oxidized Reactive Nitrogen Partitioning in Western U.S. Wildfire Smoke Plumes
Authors: Juncosa Calahorrano Julieta F. , Lindaas Jakob , O'Dell Katelyn , Palm Brett B. , Peng Qiaoyun , Flocke Frank , Pollack Ilana B. , Garofalo Lauren A. , Farmer Delphine K. , Pierce Jeffrey R. , Collett Jeffrey L. , Weinheimer Andrew , Campos Teresa , Hornbrook Rebecca S. , Hall Samuel R. , Ullmann Kirk , Pothier Matson A. , Apel Eric C. , Permar Wade , Hu Lu , Hills Alan J. , Montzka Deedee , Tyndall Geoff , Thornton Joel A. , Fischer Emily V. 
Published: December 2020

AbstractThe Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption, and Nitrogen (WE‐CAN) deployed the NSF/NCAR C‐130 aircraft in summer 2018 across the western U.S. to sample wildfire smoke during its first days of atmospheric evolution. We present a summary of a subset of reactive oxidized nitrogen species (NOy) in plumes sampled in a pseudo‐Lagrangian fashion. Emissions of nitrogen oxides (NOx = NO + NO2) and nitrous acid (HONO) are rapidly converted to more oxidized forms. Within 4 h, ∼86% of the ΣNOy is in the form of peroxy acyl nitrates (PANs) (∼37%), particulate nitrate (pNO3) (∼27%), and gas‐phase organic nitrates (Org N(g)) (∼23%). The average e‐folding time and distance for NOx are ∼90 min and ∼40 km, respectively. Nearly no enhancements in nitric acid (HNO3) were observed in plumes sampled in a pseudo‐Lagrangian fashion, implying HNO3‐limited ammonium nitrate (NH4NO3) formation, with one notable exception that we highlight as a case study. We also summarize the observed partitioning of NOy in all the smoke samples intercepted during WE‐CAN. In smoke samples intercepted above 3 km above sea level (ASL), the contributions of PANs and pNO3 to ΣNOy increase with altitude. WE‐CAN also sampled smoke from multiple fires mixed with anthropogenic emissions over the California Central Valley. We distinguish samples where anthropogenic NOx emissions appear to lead to an increase in NOx abundances by a factor of four and contribute to additional PAN formation.
Physical and chemical structure of the Serpens filament: Fast formation and gravity-driven accretion
Authors: Gong Y. , Belloche A. , Du F. J. , Menten K. M. , Henkel C. , Li G. X. , Wyrowski F. , Mao R. Q. 
Published: December 2020

Context.The Serpens filament, a prominent elongated structure in a relatively nearby molecular cloud, is believed to be at an early evolutionary stage, so studying its physical and chemical properties can shed light on filament formation and early evolution.Aims.The main goal is to address the physical and chemical properties as well as the dynamical state of the Serpens filament at a spatial resolution of ~0.07 pc and a spectral resolution of ≲0.1 km s−1.Methods.We performed13CO (1–0), C18O (1–0), C17O (1–0),13CO (2–1), C18O (2–1), and C17O (2–1) imaging observations toward the Serpens filament with the Institut de Radioastronomie Millimétrique 30-m and Atacama Pathfinder EXperiment telescopes.Results.Widespread narrow13CO (2–1) self-absorption is observed in this filament, causing the13CO morphology to be different from the filamentary structure traced by C18O and C17O. Our excitation analysis suggests that the opacities of C18O transitions become higher than unity in most regions, and this analysis confirms the presence of widespread CO depletion. Further we show that the local velocity gradients have a tendency to be perpendicular to the filament’s long axis in the outskirts and parallel to the large-scale magnetic field direction. The magnitudes of the local velocity gradients decrease toward the filament’s crest. The observed velocity structure can be a result of gravity-driven accretion flows. The isochronic evolutionary track of the C18O freeze-out process indicates the filament is young with an age of ≲2 Myr.Conclusions.We propose that the Serpens filament is a newly-formed slightly-supercritical structure which appears to be actively accreting material from its ambient gas.
Stellar chromospheric activity of 1674 FGK stars from the AMBRE-HARPS sample
Authors: Gomes da Silva J. , Santos N. C. , Adibekyan V. , Sousa S. G. , Campante T. L. , Figueira P. , Bossini D. , Delgado-Mena E. , Monteiro M. J. P. F. G. , de Laverny P. , Recio-Blanco A. , Lovis C. 
Published: December 2020

Aims.The main objective of this project is to characterise chromospheric activity of FGK stars from the HARPS archive. We start, in this first paper, by presenting a catalogue of homogeneously determined chromospheric emission (CE), stellar atmospheric parameters, and ages for 1674 FGK main sequence (MS), subgiant, and giant stars. The analysis of CE level and variability is also performed.Methods.We measured CE in the Ca IIH&K lines using more than 180 000 high-resolution spectra from the HARPS spectrograph, as compiled in the AMBRE project, obtained between 2003 and 2019. We converted the fluxes to bolometric and photospheric corrected chromospheric emission ratio,RHK′. Stellar atmospheric parametersTeff, logg, and [Fe/H] were retrieved from the literature or determined using a homogeneous method.M⋆,R⋆, and ages were determined from isochrone fitting.Results.We show that our sample has a distribution of CE for MS stars that is consistent with an unbiased sample of solar-neighbour MS stars. We analysed the CE distribution for the different luminosity classes and spectral types and confirmed the existence of the very inactive (VI) star and very active star populations at logRHK′ <  −5.1 and >  − 4.2 dex, respectively. We found indications that the VI population is composed mainly of subgiant and giant stars and that logRHK′ = −5.1 dex marks a transition in stellar evolution. Overall, CE variability decreases with decreasing CE level but its distribution is complex. There appears to be at least three regimes of variability for inactive, active, and very active stars, with the inactive and active regimes separated by a diagonal, extended Vaughan-Preston (VP) gap. We show that stars with low activity levels do not necessarily have low variability. In the case of K dwarfs, which show high CE variability, inactive and active stars have similar levels of activity variability. This means that activity levels alone are not enough to infer the activity variability of a star. We also explain the shape of the VP gap observed in the distribution of CE using the CE variability-level diagram. In the CE variability-level diagram, the Sun is located in the high-variability region of the inactive MS stars zone. A method to extract the probability density function of the CE variability for a given logRHK′level is discussed, and a python code to retrieve it is provided.
Load-velocity Profiles Change after Training Programs with Different Set Configurations
Authors: Iglesias-Soler Eliseo , Rial-Vázquez Jessica , Boullosa Daniel , Mayo Xian , Fariñas Juan , Rúa-Alonso María , Santos Luis 
Published: December 2020

AbstractThis study explored the changes in load-velocity relationship of bench press and parallel squat exercises following two programs differing in the set configuration. A randomized controlled trial was carried out in a sample of 39 physically active individuals. Participants were assigned to rest redistribution set configuration, traditional set configuration, or control groups. Over 5 weeks, the experimental groups completed 10 sessions with the 10 repetitions maximum load of both exercises. Rest redistribution sets consisted in 16 sets of 2 repetitions with 60 s of rest between sets, and 5 min between exercises, whereas traditional sets entailed 4 sets of 8 repetitions with 5 min of rest between sets and exercises. The load-velocity relationships of both exercises were obtained before and after the training period. For bench press, an increase of the velocity axis intercept, and a decrease of the slope at post-test were observed in both rest redistribution (p<0.001, G=1.264; p<0.001; G=0.997) and traditional set (p=0.01, G=0.654; p=0.001; G=0.593) groups. For squat, the slope decreased (p<0.001; G=0.588) and the velocity axis intercept increased (p<0.001; G=0.727) only in the rest redistribution group. These results show that rest redistribution sets were particularly efficient for inducing changes in the load-velocity relationship.
Role of Dkk2 in the Muscle/bone Interaction of Androgen-Deficient Mice
Authors: Iemura Shunki , Kawao Naoyuki , Akagi Masao , Kaji Hiroshi 
Published: December 2020

AbstractAndrogen deficiency is known to cause both osteoporosis and sarcopenia. Myokines, humoral factors secreted from the skeletal muscles, have recently been getting attention as the key factors related to the interactions between muscle and bone. Dickkopf (Dkk) 2 is known as an inhibitor of canonical Wnt/β-catenin signaling, and Wnt/β-catenin signaling is crucial for the maintenance of muscle and bone. The present study was therefore performed to investigate the roles of Dkk2 in the alterations of muscle and bone of androgen-deficient mice with orchidectomy (ORX). ORX significantly enhanced Dkk2 mRNA levels, but not other Dkks and secreted frizzled related proteins, in the soleus muscles of mice. Moreover, ORX enhanced serum Dkk2 levels, but not Dkk2 mRNA levels in the tibial bone tissues, the white adipose tissues and liver of mice. In simple regression analyses, serum Dkk2 levels were negatively related to trabecular bone mineral density at the tibias in mice employed in the experiments. In vitro experiments, testosterone suppressed Dkk2 mRNA levels in mouse muscle C2C12 cells. In conclusion, we showed that androgen deficiency enhances Dkk2 expression and secretion in the muscles of mice. Dkk2 might be involved in androgen deficiency-induced muscle wasting and osteopenia as a myokine linking muscle to bone.
Optical diagnosis of colorectal polyp images using a newly developed computer-aided diagnosis system (CADx) compared with intuitive optical diagnosis
Authors: van der Zander Quirine E. W. , Schreuder Ramon M. , Fonollà Roger , Scheeve Thom , van der Sommen Fons , Winkens Bjorn , Aepli Patrick , Hayee Bu'Hussain , Pischel Andreas B. , Stefanovic Milan , Subramaniam Sharmila , Bhandari Pradeep , de With Peter H. N. , Masclee Ad A. M. , Schoon Erik J. 
Published: December 2020

Abstract
Background Optical diagnosis of colorectal polyps remains challenging. Image-enhancement techniques such as narrow-band imaging and blue-light imaging (BLI) can improve optical diagnosis. We developed and prospectively validated a computer-aided diagnosis system (CADx) using high-definition white-light (HDWL) and BLI images, and compared the system with the optical diagnosis of expert and novice endoscopists.
Methods CADx characterized colorectal polyps by exploiting artificial neural networks. Six experts and 13 novices optically diagnosed 60 colorectal polyps based on intuition. After 4 weeks, the same set of images was permuted and optically diagnosed using the BLI Adenoma Serrated International Classification (BASIC).
Results CADx had a diagnostic accuracy of 88.3 % using HDWL images and 86.7 % using BLI images. The overall diagnostic accuracy combining HDWL and BLI (multimodal imaging) was 95.0 %, which was significantly higher than that of experts (81.7 %, P = 0.03) and novices (66.7 %, P < 0.001). Sensitivity was also higher for CADx (95.6 % vs. 61.1 % and 55.4 %), whereas specificity was higher for experts compared with CADx and novices (95.6 % vs. 93.3 % and 93.2 %). For endoscopists, diagnostic accuracy did not increase when using BASIC, either for experts (intuition 79.5 % vs. BASIC 81.7 %, P = 0.14) or for novices (intuition 66.7 % vs. BASIC 66.5 %, P = 0.95).
Conclusion CADx had a significantly higher diagnostic accuracy than experts and novices for the optical diagnosis of colorectal polyps. Multimodal imaging, incorporating both HDWL and BLI, improved the diagnostic accuracy of CADx. BASIC did not increase the diagnostic accuracy of endoscopists compared with intuitive optical diagnosis.
Right Sinus of Valsalva Aneurysm Mimicking Right Coronary Artery Ischemia
Authors: Bivona Antonio , Caruso Vincenzo , Shah Samir 
Published: December 2020

AbstractAn aneurysm of a single sinus of Valsalva is rare. It is usually asymptomatic and rarely discovered, unless it compresses the adjacent cardiac structures, or it presents in association with other pathology. We herein describe a case of a male, with known ischemic heart disease, collapsing after sudden back pain. A computed tomography scan demonstrated an aneurysm of the right sinus of Valsalva. The surgical repair aimed to exclude the aneurysm, preserving and reconstructing the aortic root.
New-Onset Atrial Fibrillation and Adverse In-Hospital Outcome in Patients with Acute Pulmonary Embolism
Authors: Jing Yan-Yan , Tang Ri-Bo , Xu Zhi-Yuan , Dong Jian-Zeng , Du Xin , Wu Jia-Hui , Yu Rong-Hui , Long De-Yong , Ning Man , Sang Cai-Hua , Jiang Chen-Xi , Bai Rong , Liu Nian , Wen Song-Nan , Li Song-Nan , Chen Xuan , Huang Shu-Tao , Cui Yi-Kai , Ma Chang-Sheng 
Published: December 2020

AbstractAtrial fibrillation (AF) can be secondary to acute pulmonary embolism (PE). This study aimed to investigate the prognostic impact of new-onset AF on patients with acute PE. In this study, 4,288 consecutive patients who were diagnosed with acute PE were retrospectively screened. In total, 77 patients with acute PE and new-onset AF were analyzed. Another 154 acute PE patients without AF were selected as the age- and sex-matched control group. Adverse in-hospital outcome comprised one of the following conditions: all-cause death, endotracheal intubation, cardiopulmonary resuscitation, and intravenous catecholamine therapy. The patients with new-onset AF had higher prevalence of congestive heart failure, higher simplified PE severity index (sPESI), higher creatinine, and larger left atrium diameter. The incidences of adverse in-hospital outcomes were 10.4 and 2.6% in patients with new-onset AF and no AF, respectively (p = 0.02). Patients with sPESI ≥ 1 had higher incidence of adverse in-hospital outcomes than those with sPESI = 0 (9.4 vs. 0.9%, p < 0.01). The area under the receiver operating characteristic curve of sPESI and sPESI + AF (adding 1 point for new-onset AF) scores in assessing the adverse in-hospital outcome were 0.80 (95% confidence interval [CI]: 0.68–0.93) and 0.84 (95% CI: 0.72–0.96), respectively. In multivariable analysis, sPESI ≥ 1 (odds ratio, 8.88; 95% CI: 1.10–72.07; p = 0.04) was an independent predictor of adverse in-hospital outcome. However, new-onset AF was not an independent predictor. In the population studied, sPESI is an independent predictor of adverse in-hospital outcomes, whereas new-onset AF following acute PE is not, but it may add predictive value to sPESI.
Right Atrial Thrombosis and Pulmonary Embolism: A Narrative Review
Authors: Anfinogenova Nina D. , Vasiltseva Oksana Y. , Vrublevsky Alexander V. , Vorozhtsova Irina N. , Popov Sergey V. , Smorgon Andrey V. , Mochula Olga V. , Ussov Wladimir Y. 
Published: December 2020

AbstractPrompt diagnosis of pulmonary embolism (PE) remains challenging, which often results in a delayed or inappropriate treatment of this life-threatening condition. Mobile thrombus in the right cardiac chambers is a neglected cause of PE. It poses an immediate risk to life and is associated with an unfavorable outcome and high mortality. Thrombus residing in the right atrial appendage (RAA) is an underestimated cause of PE, especially in patients with atrial fibrillation. This article reviews achievements and challenges of detection and management of the right atrial thrombus with emphasis on RAA thrombus. The capabilities of transthoracic and transesophageal echocardiography and advantages of three-dimensional and two-dimensional echocardiography are reviewed. Strengths of cardiac magnetic resonance imaging (CMR), computed tomography, and cardiac ventriculography are summarized. We suggest that a targeted search for RAA thrombus is necessary in high-risk patients with PE and atrial fibrillation using transesophageal echocardiography and/or CMR when available independently on the duration of the disease. High-risk patients may also benefit from transthoracic echocardiography with right parasternal approach. The examination of high-risk patients should involve compression ultrasonography of lower extremity veins along with the above-mentioned technologies. Algorithms for RAA thrombus risk assessment and protocols aimed at identification of patients with RAA thrombosis, who will potentially benefit from treatment, are warranted. The development of treatment protocols specific for the diverse populations of patients with right cardiac thrombosis is important.
The Role of the Transorbital Superior Eyelid Approach in the Management of Selected Spheno-orbital Meningiomas: In-Depth Analysis of Indications, Technique, and Outcomes from the Study of a Cohort of 35 Patients
Authors: Locatelli Davide , Restelli Francesco , Alfiero Tommaso , Campione Alberto , Pozzi Fabio , Balbi Sergio , Arosio Alberto , Castelnuovo Paolo 
Published: December 2020

Abstract
Objective Primary goal in spheno-orbital meningioma (SOM) surgery still remains complete resection. Nevertheless, given their highly infiltrative nature, a growing body of literature suggests to shift toward function-sparing surgeries. We here present our experience in the management of SOMs through the endoscopic superior eyelid approach (SEA).
Methods Surgical database from our multidisciplinary work group was retrospectively reviewed to identify patients treated for SOMs in the last 10 years by our senior authors, analyzing and correlating clinical, radiological, and outcome variables among the different approaches used.
Results There were 35 patients (mean age of 57.3 ± 12.86 years), with a mean follow-up of 31.5 months (range: 6–84 months). The most common preoperative complaint was proptosis (62.9%) followed by diplopia and visual deficit. Greater and lesser sphenoid wings were the areas mainly involved by the pathology (91.4% and 88.6%, respectively), whereas orbital invasion was evidenced in one-third of cases. Patients were operated on through craniotomic (48.6%), endoscopic superior eyelid (37.1%), and combined cranioendoscopic (14.3%) approaches. Simpson grades 0 to II were accomplished in 46.2% of SEA and 76.5% of craniotomies. All patients with a preoperative visual deficit improved in the postoperative period, independently from the approach used. On patients who underwent endoscopic SEA, there was improved their short-/long-term postoperative Karnofsky Performance Status.
Conclusions Endoscopic SEA is a safe and effective alternative to transcranial approaches in very selected cases of SOMs, where the planned primary objective was to obtain a maximally safe resection, aimed at symptom relief, rather than a gross total resection at any cost.
Correlation of Vitamin D Deficiency with Predictors of Mortality in Critically Ill Children at a Tertiary Care Centre in North India—A Prospective, Observational Study
Authors: Bansal Shilpa , Kaur Amarpreet , Rai Seema , Kaur Gurmeet , Goyal Gitanjali , Singh Jasbir , Sandhu Jaskirat Kaur 
Published: December 2020

AbstractThis study was conducted to assess the relationship of vitamin D deficiency (VDD) with various demographic characteristics, laboratory parameters, and predictors of mortality. This prospective observational study was performed at pediatric intensive care unit (PICU) of a tertiary care hospital situated in north India. A total of 125 children admitted in PICU with age from 2 months to 14 years were analyzed. The subjects were classified as Vitamin D deficient (≤20 ng/mL) and nondeficient (>20 ng/mL). The relationship between VDD and predictors of mortality were analyzed using correlation and multivariate analysis. Respiratory system (40%) was most commonly involved. VDD was seen in 72% of the patients. There was statistically significant correlation of VDD with age (p = 0.019), season (p = 0.018), height (p = 0.005), and weight (p = 0.003). On multivariate analysis factors associated with VDD were age (odds ratio [OR] = 1.01, 95% confidence interval [CI] 1.00–1.03, p = 0.006), season (OR = 3.98, 95% CI 1.09–14.50, p = 0.036). VDD was also correlated to bacteriuria (p = 0.033), cardiovascular sequential sepsis-related organ failure assessment score (CV-SOFA score) (p = 0.001), and mechanical ventilation (p = 0.043). On multivariate analysis, factors associated with VDD were bacteriuria (OR = 4.88, 95% CI 1.04–22.89, p = 0.04), mechanical ventilation requirement (OR = 2.95, 95% CI 1.12–7.85, p = 0.029), and CV-SOFA score (OR = 2.33, 95% CI 1.14–4.76, p = 0.021). Median (interquartile range) duration of PICU stay in VDD patients was (3–7) days while in nondeficient patients it was (2–6) days (p = 0.107). VDD was a significant risk factor for the need of mechanical ventilation, bacteriuria, and mortality among patients in our cohort.
A rate threshold mechanism regulates MAPK stress signaling and survival
Authors: Johnson Amanda N. , Li Guoliang , Jashnsaz Hossein , Thiemicke Alexander , Kesler Benjamin K. , Rogers Dustin C. , Neuert Gregor 
Published: December 2020

Significance
Signaling pathways must decide how to respond to extracellular stimulation patterns that vary widely in vivo. However, most experiments only explore how cells respond to one stimulation variable: concentration. By probing the model yeast osmostress mitogen-activated protein kinase pathway with diverse stimulation gradients we explore cellular sensitivity to multiple stimulation variables. We identify a rate threshold required for signaling and show that the timing of signaling initiation depends on both stimulation rate and concentration in finite-rate treatments. We connect our discovered limit on cell sensitivity to stimulation rate with a phenotype and molecular mechanism, demonstrating its biological relevance. Our results provide motivation and a blueprint for the dissection of other major stimulation-rate-dependent mechanisms in a variety of systems.