bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Northern Tornadoes Project: Uncovering Canada’s True Tornado Climatology
Authors: Sills David M. L. , Kopp Gregory A. , Elliott Lesley , Jaffe Aaron L. , Sutherland Liz , Miller Connell S. , Kunkel Joanne M. , Hong Emilio , Stevenson Sarah A. , Wang William 
Published: August 2020

AbstractCanada is a vast country with most of its population located along its southern border. Large areas are sparsely populated and/or heavily forested, and severe weather reports are rare when thunderstorms occur there. Thus, it has been difficult to accurately assess the true tornado climatology and risk. It is also important to establish a reliable baseline for tornado-related climate change studies. The Northern Tornadoes Project (NTP), led by Western University, is an ambitious multidisciplinary initiative aimed at detecting and documenting every tornado that occurs across Canada. A team of meteorologists and wind engineers collects research-quality data during each damage investigation via thorough ground surveys and high-resolution satellite, aircraft, and drone imaging. Crowdsourcing through social media is also key to tracking down events. In addition, NTP conducts research to improve our ability to detect and accurately assess tornadoes that affect forests, cropland, and grassland. An open data website allows sharing of resulting datasets and analyses. Pilot investigations were carried out during the warm seasons of 2017 and 2018, with the scope expanding from the detection of any tornadoes in heavily forested regions of central Canada in 2017 to the detection of all EF1+ tornadoes in Ontario plus all significant events outside of Ontario in 2018. The 2019 season was the first full campaign, systematically collecting research-quality tornado data across the entire country. To date, the project has found 89 tornadoes that otherwise would not have been identified, and increased the national tornado count in 2019 by 78%.
Thermal Chains and Entrainment in Cumulus Updrafts. Part II: Analysis of Idealized Simulations
Authors: Peters John M. , Morrison Hugh , Varble Adam C. , Hannah Walter M. , Giangrande Scott E. 
Published: August 2020

AbstractResearch has suggested that the structure of deep convection often consists of a series of rising thermals, or “thermal chain,” which contrasts with existing conceptual models that are used to construct cumulus parameterizations. Simplified theoretical expressions for updraft properties obtained in Part I of this study are used to develop a hypothesis explaining why this structure occurs. In this hypothesis, cumulus updraft structure is strongly influenced by organized entrainment below the updraft’s vertical velocity maximum. In a dry environment, this enhanced entrainment can locally reduce condensation rates and increase evaporation, thus eroding buoyancy. For moderate-to-large initial cloud radius R, this breaks up the updraft into a succession of discrete pulses of rising motion (i.e., a thermal chain). For small R, this leads to the structure of a single, isolated rising thermal. In contrast, moist environments are hypothesized to favor plume-like updrafts for moderate-to-large R. In a series of axisymmetric numerical cloud simulations, R and environmental relative humidity (RH) are systematically varied to test this hypothesis. Vertical profiles of fractional entrainment rate, passive tracer concentration, buoyancy, and vertical velocity from these runs agree well with vertical profiles calculated from the theoretical expressions in Part I. Analysis of the simulations supports the hypothesized dependency of updraft structure on R and RH, that is, whether it consists of an isolated thermal, a thermal chain, or a plume, and the role of organized entrainment in driving this dependency. Additional three-dimensional (3D) turbulent cloud simulations are analyzed, and the behavior of these 3D runs is qualitatively consistent with the theoretical expressions and axisymmetric simulations.
Lilly’s Model for Steady-State Tropical Cyclone Intensity and Structure
Authors: Tao Dandan , Rotunno Richard , Bell Michael 
Published: August 2020

AbstractThis study revisits the axisymmetric tropical cyclone (TC) theory from D. K. Lilly’s unpublished manuscript (Lilly model) and compares it to axisymmetric TC simulations from a nonhydrostatic cloud model. Analytic solutions of the Lilly model are presented through simplifying assumptions. Sensitivity experiments varying the sea surface, boundary layer and tropopause temperatures, and the absolute angular momentum (M) at some outer radius in the Lilly model show that these variations influence the radial structure of the tangential wind profile V(r) at the boundary layer top. However, these parameter variations have little effect on the inner-core normalized tangential wind, V(r/rm)/Vm, where Vm is the maximum tangential wind at radius rm. The outflow temperature T∞ as a function of M (or saturation entropy s*) is found to be the only input that changes the normalized tangential wind radial structure in the Lilly model. In contrast with the original assumption of the Lilly model that T∞(s*) is determined by the environment, it is argued here that T∞(s*) is determined by the TC interior flow under the environmental constraint of the tropopause height. The present study shows that the inner-core tangential wind radial structure from the Lilly model generally agrees well with nonhydrostatic cloud model simulations except in the eyewall region where the Lilly model tends to underestimate the tangential winds due to its balanced-dynamics assumptions. The wind structure in temperature–radius coordinates from the Lilly model can largely reproduce the numerical simulation results. Though the Lilly model is based on a number of simplifying assumptions, this paper shows its utility in understanding steady-state TC intensity and structure.
Hawaiian Regional Climate Variability during Two Types of El Niño
Authors: Lu Bo-Yi , Chu Pao-Shin , Kim Sung-Hun , Karamperidou Christina 
Published: August 2020

AbstractThe large-scale atmospheric circulation of the North Pacific associated with two types of El Niño—the eastern Pacific (EP) and central Pacific (CP)—is studied in relation to Hawaiian winter (December–February) rainfall and temperature. The eastern and central equatorial Pacific undergo active convective heating during EP El Niño winters. The local Hadley circulation is enhanced and an upper-level westerly jet stream of the North Pacific is elongated eastward. Due to the impact of both phenomena, stronger anomalous descending motion, moisture flux divergence anomalies near Hawaii, and reduction of easterly trade winds, which are characteristic of EP winters, are unfavorable for winter rainfall in Hawaii. As a result of this robust signal, dry conditions prevail in Hawaii and the standard deviation of rainfall during EP winters is smaller than the climatology. For CP winters, the maximum equatorial ocean warming is weaker and shifted westward to near the date line. The subtropical jet stream retreats westward relative to EP winters and the anomalously sinking motion near Hawaii is variable and generally weaker. Although the anomalous moisture flux divergence still exists over the subtropical North Pacific, its magnitude is weaker relative to EP winters. Without strong external forcing, rainfall in the Hawaiian Islands during CP winters is close to the long-term mean. The spread of rainfall from one CP event to another is also larger. The near-surface minimum temperature from three stations in Hawaii reveals cooling during EP winters and slight warming during CP winters.
Key Role of Diabatic Processes in Regulating Warm Water Volume Variability over ENSO Events
Authors: Huguenin Maurice F. , Holmes Ryan M. , England Matthew H. 
Published: August 2020

AbstractThe equatorial Pacific warm water volume (WWV), defined as the volume of water warmer than 20°C near the equator, is a key predictor for El Niño–Southern Oscillation (ENSO), and yet much about the individual processes that influence it remains unknown. In this study, we conduct idealized ENSO simulations forced with symmetric El Niño– and La Niña–associated atmospheric anomalies as well as a historical 1979–2016 hindcast simulation. We use the water mass transformation framework to examine the individual contributions of diabatic and adiabatic processes to changes in WWV. We find that in both sets of simulations, El Niño’s discharge and La Niña’s recharge periods are initiated by diabatic fluxes of volume across the 20°C isotherm associated with changes in surface forcing and vertical mixing. Changes in adiabatic horizontal volume transport above 20°C between the equator and subtropical latitudes dominate at a later stage. While surface forcing and vertical mixing deplete WWV during El Niño, surface forcing during La Niña drives a large increase partially compensated for by a decrease driven by vertical mixing. On average, the ratio of diabatic to adiabatic contributions to changes in WWV during El Niño is about 40% to 60%; during La Niña this ratio changes to 75% to 25%. The increased importance of the diabatic processes during La Niña, especially the surface heat fluxes, is linked to the shoaling of the 20°C isotherm in the eastern equatorial Pacific and is a major source of asymmetry between the two ENSO phases, even in the idealized simulations where the wind forcing and adiabatic fluxes are symmetric.
Exploring the Factors Influencing the Strength and Variability of Convectively Coupled Mixed Rossby–Gravity Waves
Authors: Suhas E. , Neena J. M. , Jiang Xianan 
Published: August 2020

AbstractThe three-dimensional structure, horizontal and vertical propagation characteristics, and convection–circulation coupling of the convectively coupled westward-propagating mixed Rossby–gravity (MRG) waves are examined by classifying the waves based on their amplitude. Convective signals of the MRG waves were identified and isolated using empirical orthogonal function analysis of wavenumber–frequency-filtered outgoing longwave radiation (OLR) data. It was found that about 50% of the MRG waves occur during the August–November months, and this strong seasonality was considered while characterizing the MRG waves. Five strong and five weak MRG wave seasons were identified during 1979–2019, based on seasonal wave amplitude, and through this classification, significant differences in the strength of convection–circulation coupling, zonal scale of circulation, vertical structure, and propagation characteristics of MRG waves were brought out. It was also found that the seasonal mean background state is significantly different during strong and weak MRG wave seasons. While a La Niña–like background state was found to favor enhanced MRG wave activity, the MRG wave activity is mostly suppressed during an El Niño–like background state. The presence of extratropical wave intrusions is another factor that distinguishes the strong MRG wave seasons from the weak ones. Eastward- and northeastward-propagating extratropical wave trains from the South Atlantic to the east Indian Ocean were observed during strong MRG wave seasons.
On the Wave State Dependence of the Sea Surface Roughness at Moderate Wind Speeds under Mixed Wave Conditions
Authors: Li Shuiqing , Zou Zhongshui , Zhao Dongliang , Hou Yijun 
Published: August 2020

AbstractWind stress depends on the sea surface roughness, which can be significantly changed by surface wind waves. Based on observations from a fixed platform, we examined the dependences of the sea surface roughness length on dominant wave characteristic parameters (wave age, wave steepness) at moderate wind speeds and under mixed-wave conditions. No obvious trend was found in the wave steepness dependence of sea surface roughness, but a wave steepness threshold behavior was readily identified in the wave age dependence of sea surface roughness. The influence of dominant wind waves on the surface roughness was illustrated using a wind–wave coupling model. The wave steepness threshold behavior is assumed to be related to the onset of dominant wave breaking. The important role of the interaction between swell and wind wave was highlighted, as swell can absorb energy from locally generated wind wave, which subsequently reduces the wave steepness and the probability of dominant wave breaking.
The Effect of Substance Abuse Programs on Positive Drug Screening Tests in Trauma Patients
Authors: Hale Jessica V. , Feyh Andrew S. , Weaver Andrew , Murray Jenny , Denning David A. , Amiri Farzad 
Published: August 2020

Background According to the National Institute on Drug Abuse, West Virginia has the highest age-adjusted rate of drug overdose deaths involving opioids. To combat this crisis, comprehensive drug counseling support services were established within the Cabell Huntington Hospital (CHH) system in October 2018 in Huntington, WV, USA. The purpose of this study was to investigate whether these services significantly reduced the number of trauma patients with a positive urine drug screen (UDS) seen at CHH. Methods The trauma registry at CHH was used to obtain data on trauma patients with positive UDS from January 2017 to October 2019, which was divided into groups before and after October 2018. Exclusion criteria were any patients who were prescribed the drug. The percentages of the total number of positive drug screens within each group were calculated, and a t-test analysis was performed to determine the P values. Results 345 trauma patients with positive UDS were selected. Results showed that there was an overall decrease in the rate of nonprescribed use after October 2018 of benzodiazepines (18.1%-11.5%), cocaine (19.5%-15.3%), opioids (19.1%-12.3%), and oxycodone (10.2%-4.6%). However, none of these changes were statistically significant. There was an increase in the rate of nonprescribed use of amphetamine (20.0%-23.8%) and methamphetamine (14.4%-33.8%). Discussion Our hypothesis is that the support systems are relatively new, and may need more time to identify and intervene on patients before a statistically significant effect on drug abuse rates in our region can be seen.
Gastrointestinal Bleeding in Mechanical Cardiac Support
Authors: McNally Alexander P. , Bandy Nicholas L. , Yahn Colten , Luo Jiangtao , Collins Jay 
Published: August 2020

Background Mechanical cardiac support (MCS) is a lifesaving therapy option in patients with heart failure and other medical disorders. However, there is an associated risk of gastrointestinal bleeding (GIB). The goal of this study was to determine GIB incidence and associated risk factors. Methods All patients at one institution from 2009 to 2018 under durable and nondurable support were retrospectively reviewed for GIB during their MCS period. Clinical records were evaluated for patient demographics, GIB characteristics, and interventions. Univariate and multivariate analyses were performed to compare patient groups. Results A total of 427 patients were reviewed, with 111 (25.9%) patients representing 218 episodes of GIB during our study period. The incidence rate from support initiation to GIB was 44.9% by 6 months and 60.6% in 12 months, occurring at a mean of 216.7 days. Higher rates of bleeding were found in patients with hypertension (82% vs 71.5%; P = .03) and diabetes mellitus (62.2% vs 38.3%; P < .0001), as well as pulmonary (48.7% vs 35.4%; P = .014), hepatic (21.6% vs 10.4%; P = .003), and renal disease (48.7% vs 37.3%; P = .037). Endoscopy revealed an upper GI source in 56% (n = 123) of bleeds. The most common etiology of bleeding included angiodysplasia/vascular malformation (35.7%). Therapeutic intervention was performed in 109 (50%) cases, with only 1 surgical intervention. Discussion Overall, GIB can be a significant adverse event in patients under mechanical cardiac support, so proper management of anticoagulation and early endoscopy evaluation remains of great importance.
Toward the Use of Pupillary Responses for Pilot Selection
Authors: Matton Nadine , Paubel Pierre-Vincent , Puma Sébastien 
Published: August 2020

Objective For selection practitioners, it seems important to assess the level of mental resources invested in order to perform a demanding task. In this study, we investigated the potential of pupil size measurement to discriminate the most proficient pilot students from the less proficient. Background Cognitive workload is known to influence learning outcome. More specifically, cognitive difficulties observed during pilot training are often related to a lack of efficient mental workload management. Method Twenty pilot students performed a laboratory multitasking scenario, composed of several stages with increasing workload, while their pupil size was recorded. Two levels of pilot students were compared according to the outcome after 2 years of training: high success and medium success. Results Our findings suggested that task-evoked pupil size measurements could be a promising predictor of flight training difficulties during the 2-year training. Indeed, high-level pilot students showed greater pupil size changes from low-load to high-load stages of the multitasking scenario than medium-level pilot students. Moreover, average pupil diameters at the low-load stage were smallest for the high-level pilot students. Conclusion Following the neural efficiency hypothesis framework, the most proficient pilot students supposedly used their mental resources more efficiently than the least proficient while performing the multitasking scenario. Application These findings might introduce a new way of managing selection processes complemented with ocular measurements. More specifically, pupil size measurement could enable identification of applicants with greater chances of success during pilot training.
Transitions Between Highly Automated and Longitudinally Assisted Driving: The Role of the Initiator in the Fight for Authority
Authors: Maggi Davide , Romano Richard , Carsten Oliver 
Published: August 2020

Objective A driving simulator study explored how drivers behaved depending on their initial role during transitions between highly automated driving (HAD) and longitudinally assisted driving (via adaptive cruise control). Background During HAD, drivers might issue a take-over request (TOR), initiating a transition of control that was not planned. Understanding how drivers behave in this situation and, ultimately, the implications on road safety is of paramount importance. Method Sixteen participants were recruited for this study and performed transitions of control between HAD and longitudinally assisted driving in a driving simulator. While comparing how drivers behaved depending on whether or not they were the initiators, different handover strategies were presented to analyze how drivers adapted to variations in the authority level they were granted at various stages of the transitions. Results Whenever they initiated the transition, drivers were more engaged with the driving task and less prone to follow the guidance of the proposed strategies. Moreover, initiating a transition and having the highest authority share during the handover made the drivers more engaged with the driving task and attentive toward the road. Conclusion Handover strategies that retained a larger authority share were more effective whenever the automation initiated the transition. Under driver-initiated transitions, reducing drivers’ authority was detrimental for both performance and comfort. Application As the operational design domain of automated vehicles (Society of Automotive Engineers [SAE] Level 3/4) expands, the drivers might very well fight boredom by taking over spontaneously, introducing safety issues so far not considered but nevertheless very important.
The Prevalence of Occupational Burnout Among Ophthalmologists: A Systematic Review and Meta-Analysis
Authors: Cheung Ronald , Yu Brian , Iordanous Yiannis , Malvankar-Mehta Monali S. 
Published: August 2020

Objective To investigate the prevalence of occupational burnout among ophthalmologists in order to better understand the mental and physical well-being of eye physicians and surgeons in the professional workplace. Study Design A systematic review and meta-analysis. Methods Online computer databases MEDLINE, EMBASE, CINAHL, and ProQuest Dissertations and Theses were searched systematically and thoroughly. Conferences held through Association for Research in Vision and Ophthalmology, American Academy of Ophthalmology, and Canadian Society of Ophthalmology were searched. Studies were screened using Covidence software. Data on reported burnout prevalence was extracted. STATA 15.0 was used to conduct meta-analysis. Synthesis: Our search strategy identified 318 records from online databases and 11 records from grey literature search, which were screened at 2-levels. Title and abstracts of each record were screened resulting in 24 records moving to full-text screening. Total of 9 records were utilized for quantitative analysis in the data extraction stage. Our results indicated significant professional burnout among ophthalmologists (ES = 0.41; CI: [0.26, 0.56]) with significant emotional exhaustion (ES = 0.43; CI: [0.33, 0.53]), depersonalization (ES = 0.29; CI: [0.13, 0.46]), and a low sense of personal accomplishment (ES = 0.36; CI: [0.08, 0.63]). Conclusions Significant occupational burnout among ophthalmologists is concerning because burnout can have a negative effect on the physical and mental health of eye physicians and surgeons. It could impact productivity, cutbacks in work hours, or lead to early retirement from the profession. Contributing factors in ophthalmologist burnout including work overload need to be addressed in a timely manner.
The role of neutrophil-lymphocyte ratio and lymphocyte–monocyte ratio in the prognosis of type 2 diabetics with COVID-19
Authors: Liu Gaoli , Zhang Shaowen , Hu Haifeng , Liu TingTing , Huang Jie 
Published: August 2020

Objectives To assess the prognostic value of neutrophil-lymphocyte ratio, lymphocyte–monocyte ratio and red cell distribution width in type 2 diabetics with COVID-19. Methods We collected the data of type 2 diabetics with COVID-19 treated in our hospital from January 28 to March 15, 2020 and performed a retrospective analysis. Using severity, duration of hospital stay, and the time required for nucleic acid results became negative as prognostic indicators, we explored the relationship between these inflammation-based markers and prognosis of type 2 diabetics with COVID-19. Results A total of 134 type 2 diabetics with COVID-19 were selected for this study. Correlation analysis showed that NLR, LMR and RDW were correlated with prognosis ( P < 0.05). In multivariate regression analysis after controlling for the relevant confounding factors, COVID-19 diabetes patients with higher NLR had heavier severity, longer duration of hospital stay, more time required for nucleic acid results became negative, and heavier hospital expenses ( P < 0.05). ROC curve result displayed that higher NLR predicted all prognostic indicators with statistical significance, and lower LMR predicted severe and extremely severe with statistical significance ( P < 0.05). Conclusions NLR is a more powerful and practical marker for predicting the prognosis of type 2 diabetic COVID-19 patients that is simple and fast.