A climatology of cell mergers with supercells and their association with mesocyclone evolution

2021 ◽  
Author(s):  
Martin A. Satrio ◽  
Madeline R. Diedrichsen ◽  
Michael C. Coniglio ◽  
Sean Waugh
Keyword(s):  
Inverse Relationship ◽  
Temporal Evolution ◽  
Time Of Day ◽  
Temporal Changes ◽  
Geographical Region ◽  
Future Research ◽  
Physical Processes ◽  
Low Level ◽  
Azimuthal Shear ◽  
The Impact

Abstract In this study, we present a climatology of observed cell mergers along the paths of 342 discrete, right-moving supercells and their association with temporal changes in low-level mesocyclone strength (measured using azimuthal shear). Nearly half of the examined supercells experience at least one cell merger. The frequency of cell merger occurrence varies somewhat by geographical region and the time of day. No general relationship exists between cell merger occurrence and temporal changes in low-level azimuthal shear; this corroborates prior studies in showing that the outcome of a merger is probably sensitive to storm-scale and environmental details not captured in this study. Interestingly, we find a significant inverse relationship between pre-merger azimuthal shear and the subsequent temporal evolution of azimuthal shear. In other words, stronger low-level mesocyclones are more likely to weaken after cell mergers, and weaker low-level mesocyclones are more likely to strengthen. We also show that shorter-duration cell merger “events” (comprised of multiple individual mergers) are more likely to be associated with a steady or weakening low-level mesocyclone, while longer-duration cell merger events (3–4 individual mergers) are more likely to be associated with a strengthening low-level mesocyclone. These findings suggest what physical processes may influence the outcome of a merger in different scenarios and that the impact of these processes on low-level mesocyclone strength may change depending on storm maturity. We establish a baseline understanding of the supercell-cell merger climatology and highlight areas for future research in how to better anticipate the outcomes of cell mergers.

scholarly journals P004: Effect of telephone triage (811) calls on a regional poison centre

CJEM ◽  
2019 ◽  
Vol 21 (S1) ◽  
pp. S64
Author(s):  
S. Alrobaian ◽  
K. Hurley ◽  
E. Fitzpatrick ◽  
L. Mosher ◽  
M. Young ◽  
...  
Keyword(s):  
Care Facility ◽  
Time Of Day ◽  
Categorical Variables ◽  
Future Research ◽  
Telephone Triage ◽  
Poison Centre ◽  
Phone Calls ◽  
The Impact ◽  
Watson Statistic ◽  
Call Volume

Introduction: Telephone Triage Services (TTS) manage phone calls from the public regarding general medical problems and provide telephone advice. This telephone based care can overlap with care provided by Poison Centres. Our objective was to examine the impact of a provincial 811 TTS on the IWK Regional Poison Centre (RPC). Methods: This is a retrospective descriptive study using interrupted time series methodology. We compared monthly IWK RPC call volume in the pre-811 era (January 2007-July 2009) and the post-811 era (September 2009-December 2017). We summarized the characteristics of callers who accessed the IWK RPC in terms of client age, sex, intentionality, time of day, call disposition and outcome. Caller characteristics were compared between the pre- and post-811 eras using chi-square test for categorical variables. We used segmented regression analysis to evaluate changes in slope of call volume in the pre- and post 811 eras. The Durbin-Watson statistic was performed to test for serial correlation and the Dickey-Fuller test to investigate seasonality. Results: The dataset included 82683 calls to the IWK RPC – 27028 pre-811 and 55655 post-811. Overall, 55% of calls were for female clients and the largest age group was children aged 0-5 years (37%). Most calls originated from home (47%), followed by a health care facility (23%). Most calls were managed at home (65%). Less than 3% of calls resulted in major effect or death. The Durbin Watson statistic was not statistically significant (p = 0.94). The Dickey-Fuller test indicated series stationarity (p = 0.001). There was no statistically significant change in call volume to the IWK RPC due to the introduction of 811 (p = 0.39). There was no significant variation by time of day, day of week or month, with most calls occurring in the evening. There were significantly more calls regarding intentional ingestions in the post-811 era (23% vs. 19% pre-811, p < .001). Outcomes in the pre and post 811 eras were as follows: minor/no effect/non-toxic/minimal 80% vs. 78%; moderate 7% vs. 10%; and, major/death 1.7% vs. 2.0%. Conclusion: The introduction of a TTS did not change call volumes at our RPC. The increase in the percentage of calls about intentional ingestions may reflect an increase in call acuity as the 811-TTS likely manages calls about minor/non-toxic ingestions without consulting with the RPC. Our future research will examine the nature of poison related calls to the 811-TTS.

scholarly journals Synoptic, thermodynamic and agroeconomic aspects of severe hail events in Cyprus

2008 ◽  
Vol 8 (3) ◽  
pp. 461-471 ◽  
Author(s):  
S. C. Michaelides ◽  
K. Savvidou ◽  
K. A. Nicolaides ◽  
A. Orphanou ◽  
G. Photiou ◽  
...  
Keyword(s):  
Thermal Instability ◽  
Temporal Evolution ◽  
Thermodynamic Characteristics ◽  
Thunderstorm Activity ◽  
Local Economy ◽  
Synoptic Scale ◽  
Physical Processes ◽  
Agricultural Insurance ◽  
Dynamic Mechanisms ◽  
The Impact

Abstract. Hail is a hazardous weather element often accompanying a thunderstorm, as a result of either thermal instability or instability associated with baroclinic synoptic-scale systems (i.e. frontal depressions). Nevertheless, instability of any kind and thunderstorm activity does not always lead to the formation of hail of adequate size to reach the ground. The broader the knowledge concerning hail events the better the understanding of the underlying thermodynamic and dynamic mechanisms, as well as the physical processes associated with its formation. In the present study, the severe hail events that were recorded in Cyprus during the ten-year period from 1996 until 2005 were examined, first by grouping them into two clusters, namely, the "thermal instability cluster" and the "frontal depression cluster". Subsequently, the spatial and temporal evolution of the synoptic, dynamic and thermodynamic characteristics of these hail events was studied in depth. Also, the impact of hailstorms on the local economy of the island is presented in terms of the compensations paid by the Agricultural Insurance Organization of the country.

Effects of Illuminance and Correlated Color Temperature on Daytime Cognitive Performance, Subjective Mood, and Alertness in Healthy Adults

2017 ◽  
Vol 51 (2) ◽  
pp. 199-230 ◽  
Author(s):  
Yingying Zhu ◽  
Minqi Yang ◽  
Ying Yao ◽  
Xiao Xiong ◽  
Xiaoran Li ◽  
...  
Keyword(s):  
Cognitive Performance ◽  
Light Exposure ◽  
Bright Light ◽  
Time Of Day ◽  
Healthy Adults ◽  
Color Temperature ◽  
Future Research ◽  
Long Term Memory ◽  
Indoor Lighting ◽  
The Impact

This study investigated the impact of indoor illuminance and correlated color temperature (CCT) on healthy adults’ cognitive performance, subjective mood, and alertness during daytime office hours and differences in time-of-day effects. A 2(illuminance) × 2(CCT) × 2(morning vs. afternoon) mixed design ( N = 60) was employed. Participants felt less sleepy in the bright light exposure. The low “cool” lighting induced the least positive mood. The effects of illuminance and CCT on subjective feelings were not time-of-day dependent. The results demonstrated the slowest responses in inhibition, working memory, and recognition of facial expression tasks in the low “warm” lighting. The effect on long-term memory was most pronounced under the high “cool” light exposure, but only in the afternoon for recognition of neutral words. The findings suggest that future research on good indoor lighting should consider illuminance levels and CCT as well as other variables to optimize lighting effects during regular daytime hours.

scholarly journals Trichothecenes in Food and Feed, Relevance to Human and Animal Health and Methods of Detection: A Systematic Review

Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 454
Author(s):  
Magdalena Polak-Śliwińska ◽  
Beata Paszczyk
Keyword(s):  
Environmental Conditions ◽  
Animal Health ◽  
Agricultural Practices ◽  
Climatic Conditions ◽  
Toxic Effects ◽  
Farm Animals ◽  
Future Research ◽  
Low Level ◽  
Food And Feed ◽  
The Impact

Trichothecene mycotoxins are sesquiterpenoid compounds primarily produced by fungi in taxonomical genera such as Fusarium, Myrothecium, Stachybotrys, Trichothecium, and others, under specific climatic conditions on a worldwide basis. Fusarium mold is a major plant pathogen and produces a number of trichothecene mycotoxins including deoxynivalenol (or vomitoxin), nivalenol, diacetoxyscirpenol, and T-2 toxin, HT-2 toxin. Monogastrics are sensitive to vomitoxin, while poultry and ruminants appear to be less sensitive to some trichothecenes through microbial metabolism of trichothecenes in the gastrointestinal tract. Trichothecene mycotoxins occur worldwide however both total concentrations and the particular mix of toxins present vary with environmental conditions. Proper agricultural practices such as avoiding late harvests, removing overwintered stubble from fields, and avoiding a corn/wheat rotation that favors Fusarium growth in residue can reduce trichothecene contamination of grains. Due to the vague nature of toxic effects attributed to low concentrations of trichothecenes, a solid link between low level exposure and a specific trichothecene is difficult to establish. Multiple factors, such as nutrition, management, and environmental conditions impact animal health and need to be evaluated with the knowledge of the mycotoxin and concentrations known to cause adverse health effects. Future research evaluating the impact of low-level exposure on livestock may clarify the potential impact on immunity. Trichothecenes are rapidly excreted from animals, and residues in edible tissues, milk, or eggs are likely negligible. In chronic exposures to trichothecenes, once the contaminated feed is removed and exposure stopped, animals generally have an excellent prognosis for recovery. This review shows the occurrence of trichothecenes in food and feed in 2011–2020 and their toxic effects and provides a summary of the discussions on the potential public health concerns specifically related to trichothecenes residues in foods associated with the exposure of farm animals to mycotoxin-contaminated feeds and impact to human health. Moreover, the article discusses the methods of their detection.

scholarly journals Neural representation of words within phrases: Temporal evolution of color-adjectives and object-nouns during simple composition

2020 ◽  
Author(s):  
Maryam Honari-Jahromi ◽  
Brea Chouinard ◽  
Esti Blanco-Elorrieta ◽  
Liina Pylkkänen ◽  
Alona Fyshe
Keyword(s):  
Picture Naming ◽  
Temporal Evolution ◽  
Naming Task ◽  
Neural Representation ◽  
Future Research ◽  
Crack Open ◽  
Speech Planning ◽  
The Impact ◽  
Over Time ◽  
Time Point

ABSTRACTIn language, stored representations of lexical items combine into an infinitude of complex expressions. While the neuroscience of composition has begun to mature, we do not yet understand how the stored representations evolve and morph during composition. New decoding techniques allow us to crack open this very hard question: we can train a model to recognize a representation in one context or time-point and assess its accuracy in another. We combined the decoding approach with magnetoencephalography recorded during a picture naming task to investigate the temporal evolution of noun and adjective representations during speech planning. We tracked word representations as they combined into simple two-word phrases, using single words and two-word lists as non-combinatory controls. We found that nouns were generally more decodable than adjectives, suggesting that noun representations were stronger and/or more consistent across trials than those of adjectives. When training and testing across contexts and times, the representations of isolated nouns were recoverable when those nouns were embedded in phrases, but not so if they were embedded in lists. Adjective representations did not show a similar consistency across isolated and phrasal contexts. Noun representations in phrases also sustained over time in a way that was not observed for any other pairing of word class and context. These findings offer a new window into the temporal evolution and context sensitivity of word representations during composition, revealing a clear asymmetry between adjectives and nouns. The impact of phrasal contexts on the decodability of nouns may be due to the nouns’ status as head of phrase—an intriguing hypothesis for future research.

scholarly journals The Circulation Response of a Two-Dimensional Frontogenetic Model to Optimized Moisture Perturbations

2020 ◽  
Author(s):  
Reuben Demirdjian ◽  
Richard Rotunno ◽  
Bruce Cornuelle ◽  
Carolyn A. Reynolds ◽  
James D. Doyle
Keyword(s):  
Three Dimensional ◽  
Static Stability ◽  
Two Dimensional ◽  
Mixing Ratio ◽  
Physical Processes ◽  
Low Level ◽  
Nonlinear Growth ◽  
Idealized Model ◽  
The Impact ◽  
Transverse Circulation

AbstractAn analysis of the influence and sensitivity of moisture in an idealized two-dimensional moist semigeostrophic frontogenesis model is presented. A comparison between a dry (relative humidity, RH=0%) and moist (RH=80%) version of the model demonstrates that the impact of moisture is to increase frontogenesis, strengthen the transverse circulation (??????,??), generate a low-level potential-vorticity anomaly and develop a low-level jet. The idealized model is compared to a real case simulated with the full-physics three-dimensional Coupled Ocean-Atmospheric Mesoscale Prediction System (COAMPS) model establishing good agreement and thereby confirming that the idealized model retains the essential physical processes relevant for improving understanding of midlatitude frontogenesis. Optimal perturbations of mixing ratio are calculated to quantify the circulation response of the model through the computation of singular vectors, which determines the fastest-growing modes of a linearized version of the idealized model. The vertical velocity is found to respond strongly to initial-condition mixing-ratio perturbations such that small changes in moisture lead to large changes in the ascent. The progression of physical processes responsible for this nonlinear growth is (in order): jet/front transverse circulation → moisture convergence ahead of the front → latent heating at mid-to-low elevations → reduction in static stability ahead of the front → strengthening of the transverse circulation, and the feedback cycle repeats. Together, these physical processes represent a pathway by which small perturbations of moisture can strongly impact a forecast involving midlatitude frontogenesis.

scholarly journals Neural representation of words within phrases: Temporal evolution of color-adjectives and object-nouns during simple composition

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0242754
Author(s):  
Maryam Honari-Jahromi ◽  
Brea Chouinard ◽  
Esti Blanco-Elorrieta ◽  
Liina Pylkkänen ◽  
Alona Fyshe
Keyword(s):  
Picture Naming ◽  
Temporal Evolution ◽  
Naming Task ◽  
Neural Representation ◽  
Future Research ◽  
Semantic Representations ◽  
Crack Open ◽  
Speech Planning ◽  
The Impact ◽  
Time Point

In language, stored semantic representations of lexical items combine into an infinitude of complex expressions. While the neuroscience of composition has begun to mature, we do not yet understand how the stored representations evolve and morph during composition. New decoding techniques allow us to crack open this very hard question: we can train a model to recognize a representation in one context or time-point and assess its accuracy in another. We combined the decoding approach with magnetoencephalography recorded during a picture naming task to investigate the temporal evolution of noun and adjective representations during speech planning. We tracked semantic representations as they combined into simple two-word phrases, using single words and two-word lists as non-combinatory controls. We found that nouns were generally more decodable than adjectives, suggesting that noun representations were stronger and/or more consistent across trials than those of adjectives. When training and testing across contexts and times, the representations of isolated nouns were recoverable when those nouns were embedded in phrases, but not so if they were embedded in lists. Adjective representations did not show a similar consistency across isolated and phrasal contexts. Noun representations in phrases also sustained over time in a way that was not observed for any other pairing of word class and context. These findings offer a new window into the temporal evolution and context sensitivity of word representations during composition, revealing a clear asymmetry between adjectives and nouns. The impact of phrasal contexts on the decodability of nouns may be due to the nouns’ status as head of phrase—an intriguing hypothesis for future research.

scholarly journals A Composite Perspective on Bore Passages during the PECAN Campaign

2019 ◽  
Vol 147 (4) ◽  
pp. 1395-1413 ◽  
Author(s):  
David M. Loveless ◽  
Timothy J. Wagner ◽  
David D. Turner ◽  
Steven A. Ackerman ◽  
Wayne F. Feltz
Keyword(s):  
Water Vapor ◽  
Observational Studies ◽  
Convective Available Potential Energy ◽  
Potential Temperature ◽  
Future Research ◽  
High Temporal Resolution ◽  
Convective Initiation ◽  
Low Level ◽  
Capping Inversion ◽  
The Impact

Abstract Atmospheric bores have been shown to have a role in the initiation and maintenance of elevated convection. Previous observational studies of bores have been case studies of more notable events. However, this creates a selection bias toward extraordinary cases, while discussions of the differences between bores that favor convective initiation and maintenance and bores that do not are lacking from the literature. This study attempts to fill that gap by analyzing a high-temporal-resolution thermodynamic profile composite of eight bores observed by multiple platforms during the Plains Elevated Convection at Night (PECAN) campaign in order to assess the impact of bores on the environment. The time–height cross section of the potential temperature composite displays quasi-permanent parcel displacements up to 900 m with the bore passage. Low-level lifting is shown to weaken the capping inversion and reduce convective inhibition (CIN) and the level of free convection (LFC). Additionally, low-level water vapor increases by about 1 g kg−1 in the composite mean. By assessing variability across the eight cases, it is shown that increases in low-level water vapor result in increases to convective available potential energy (CAPE), while drying results in decreased CAPE. Most cases resulted in decreased CIN and LFC height with the bore passage, but only some cases resulted in increased CAPE. This suggests that bores will increase the potential for convective initiation, but future research should be directed toward better understanding cases that result in increased CAPE as those are the types of bores that will increase severity of convection.

On the Impact of Income, Age, and Travel Distance on the Value of Time

2020 ◽  
pp. 036119812096660
Author(s):  
Nicholas Fournier ◽  
Eleni Christofa
Keyword(s):  
Gaussian Function ◽  
Time Of Day ◽  
Travel Distance ◽  
Future Research ◽  
Value Of Time ◽  
Alternative Mode ◽  
Research And Practice ◽  
Household Travel Survey ◽  
Household Travel ◽  
The Impact

The value of time (VOT) is a fundamental component used in transportation modeling, policy analysis, and economic appraisal. Decades of research and practice have empirically estimated the VOT across many factors (e.g., mode, purpose, time, comfort, etc.), yet little is known about its underlying form. Although it is well established that VOT can vary, it is still unclear whether patterns exist in this variation. The objective of this paper is not to merely estimate the VOT, but to model the VOT across multiple continuous and interacting variables. The purpose is to reveal its functional form with respect to mode, age, gender, purpose, income, and time of day to provide a generalizable understanding for future research and practice. Such an understanding can help develop simpler models and reduce the need for bespoke estimations for every conceivable variable perturbation. This research utilized a household travel survey containing 14,159 reported trips with imputed travel time and costs for the alternative mode choices. The average overall estimated VOT is 40.32 $/h, with results showing VOT varying log-linearly with income and trip distance, but following a Gaussian function (normal curve) with age. Overall, the results show that travel distance dominates VOT variation, which increases exponentially at a rate that is 3.61 times higher per mile of distance than per $10,000 of income, and that VOT by age peaks at age 54. This basic understanding of how the VOT varies sets the foundation for answering the subsequent question for why it might vary.

scholarly journals A Systematically Conducted Scoping Review of the Evidence and Fidelity of Treatments for Verb Deficits in Aphasia: Verb-in-Isolation Treatments

2020 ◽  
Vol 29 (1S) ◽  
pp. 530-559
Author(s):  
Julie Hickin ◽  
Madeline Cruice ◽  
Lucy Dipper
Keyword(s):  
Scoping Review ◽  
Clinical Decision Making ◽  
Current Evidence ◽  
Future Research ◽  
Functional Communication ◽  
Level Of Evidence ◽  
Low Level ◽  
Sufficient Detail ◽  
Treatment Research ◽  
The Impact

Purpose Aphasia research demonstrates increasing interest in the treatment of verb retrieval deficits. This systematically conducted scoping review reports on the level and fidelity of the current evidence for verb treatments; on its effectiveness regarding the production of trained and untrained verbs, functional communication, sentences, and discourse; and on the potential active ingredients. Recommendations to guide clinical decision making and future research are made. Method The computerized database search included studies from January 1980 to September 2018. The level of evidence of each study was documented, as was fidelity in terms of treatment delivery, enactment, and receipt. Studies were also categorized according to the treatment methods used. Results Thirty-seven studies were accepted into the review, and all but 1 constituted a low level of evidence. Thirty-three studies (89%) described treatment in sufficient detail to allow replication, dosage was poorly reported, and the fidelity of treatment was rarely assessed. The most commonly reported treatment techniques were phonological and semantic cueing in 25 (67.5%) and 20 (54%) studies, respectively. Retrieval of trained verbs improved for 80% of participants, and improvements generalized to untrained verbs for 15% of participants. There was not sufficient detail to evaluate the impact of treatment on sentence production, functional communication, and discourse. Conclusions The evidence for verb treatments is predominantly of a low level. There are encouraging findings in terms of treatments being replicable; however, this is tempered by poor monitoring of treatment fidelity. The quality of verb treatment research would be improved by researchers reaching consensus regarding outcome measures (including generalization to, e.g., sentences and discourse) by manualizing treatment to facilitate implementation and exploring the opinions of participants. Finally, while treatment is largely effective in improving production of trained verbs, lack of generalization to untrained items leads to the recommendation that personally relevant verbs are prioritized.

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