scholarly journals Recent Trends in Four Common Stability Indices Derived from U.S. Radiosonde Observations

2006 ◽  
Vol 19 (3) ◽  
pp. 309-323 ◽  
Author(s):  
Diana DeRubertis
Keyword(s):  
United States ◽  
Extreme Values ◽  
Convective Available Potential Energy ◽  
Atmospheric Stability ◽  
The United States ◽  
Severe Weather ◽  
Radiosonde Data ◽  
K Index ◽  
The Mean ◽  
Stability Indices

Abstract Daily sounding-derived atmospheric stability indices are typically employed for short-term severe weather forecasts. Over longer time periods, these indicators may convey changes in the potential for severe storm development over the United States. Daily (0000 UTC) observations from 48 radiosonde stations in the contiguous United States are extracted to assemble a ∼50 yr record of four common stability indices: the Lifted Index, the K-Index, convective available potential energy (CAPE), and the Air Force Severe Weather Threat Index. Because of radiosonde data inhomogeneities, the 1973–97 period is the focus of the analysis. Trends in the mean and extreme values of daily index observations are calculated for spring and summer seasons. In addition, climatological mean indices, as well as the mean frequency of index extremes, are determined for all U.S. regions. At stations free of obvious data discontinuities, the early part of the record (1948–65) is compared with more recent periods. In spring, few significant changes in either index means or extremes are reported. However, in summer, widespread trends toward enhanced instability appear, particularly in the Lifted Index, the K-Index, and CAPE. Stations in the Plains and southern states show the most consistent increases in severe weather potential, while significant trends in index extremes are uncommon in the western region, possibly due to the rarity of severe weather there.

scholarly journals Climatology of Severe Local Storm Environments and Synoptic-Scale Features over North America in ERA5 Reanalysis and CAM6 Simulation

2020 ◽  
Vol 33 (19) ◽  
pp. 8339-8365 ◽  
Author(s):  
Funing Li ◽  
Daniel R. Chavas ◽  
Kevin A. Reed ◽  
Daniel T. Dawson II
Keyword(s):  
United States ◽  
North America ◽  
Great Plains ◽  
Large Scale ◽  
Extreme Values ◽  
Convective Available Potential Energy ◽  
The United States ◽  
Synoptic Scale ◽  
Low Level ◽  
High Bias

AbstractSevere local storm (SLS) activity is known to occur within specific thermodynamic and kinematic environments. These environments are commonly associated with key synoptic-scale features—including southerly Great Plains low-level jets, drylines, elevated mixed layers, and extratropical cyclones—that link the large-scale climate to SLS environments. This work analyzes spatiotemporal distributions of both extreme values of SLS environmental parameters and synoptic-scale features in the ERA5 reanalysis and in the Community Atmosphere Model, version 6 (CAM6), historical simulation during 1980–2014 over North America. Compared to radiosondes, ERA5 successfully reproduces SLS environments, with strong spatiotemporal correlations and low biases, especially over the Great Plains. Both ERA5 and CAM6 reproduce the climatology of SLS environments over the central United States as well as its strong seasonal and diurnal cycles. ERA5 and CAM6 also reproduce the climatological occurrence of the synoptic-scale features, with the distribution pattern similar to that of SLS environments. Compared to ERA5, CAM6 exhibits a high bias in convective available potential energy over the eastern United States primarily due to a high bias in surface moisture and, to a lesser extent, storm-relative helicity due to enhanced low-level winds. Composite analysis indicates consistent synoptic anomaly patterns favorable for significant SLS environments over much of the eastern half of the United States in both ERA5 and CAM6, though the pattern differs for the southeastern United States. Overall, our results indicate that both ERA5 and CAM6 are capable of reproducing SLS environments as well as the synoptic-scale features and transient events that generate them.

scholarly journals A statistical analysis of sounding derived indices and parameters for extreme and non-extreme thunderstorm events over Cyprus

2010 ◽  
Vol 23 ◽  
pp. 79-85 ◽  
Author(s):  
K. Savvidou ◽  
A. Orphanou ◽  
D. Charalambous ◽  
P. Lingis ◽  
S. Michaelides
Keyword(s):  
Statistical Analysis ◽  
Potential Energy ◽  
Convective Available Potential Energy ◽  
Radiosonde Data ◽  
Available Potential Energy ◽  
K Index ◽  
Upper Limits ◽  
The Stability ◽  
Simple Statistical Analysis ◽  
Stability Indices

Abstract. The main purpose of this study is to provide a simple statistical analysis of several stability indices and parameters for extreme and non-extreme thunderstorm events during the period 1997 to 2001 in Cyprus. For this study, radiosonde data from Athalassa station (35°1´ N, 33°4´ E) were analyzed during the aforementioned period. The stability indices and parameters set under study are the K index, the Total Totals (TT) index, the Convective Available Potential Energy related parameters such as Convective Available Potential Energy (CAPE), Downdraft CAPE (DCAPE) and the Convective Inhibition (CIN), the Vorticity Generator Parameter (VGP), the Bulk Richardson Number (BRN), the BRN Shear and the Storm Relative Helicity (SRH). An event is categorized as extreme, if primarily, CAPE was non zero and secondary, if values of both the K and the TotalTotals (TT) indices exceeded 26.9 and 50, respectively. The cases with positive CAPE but lower values of the other indices, were identified as non-extreme. By calculating the median, the lower and upper limits, as well as the lower and upper quartiles of the values of these indices, the main characteristics of their distribution were determined.

scholarly journals Longer Residence in the United States is Associated With More Physical Function Limitations in African Immigrant Older Adults

2020 ◽  
pp. 073346482097760
Author(s):  
Manka Nkimbeng ◽  
Yvonne Commodore-Mensah ◽  
Jacqueline L. Angel ◽  
Karen Bandeen-Roche ◽  
Roland J. Thorpe ◽  
...  
Keyword(s):  
United States ◽  
Older Adults ◽  
Confidence Interval ◽  
Physical Function ◽  
Racial Discrimination ◽  
African Immigrants ◽  
The United States ◽  
African Immigrant ◽  
High Discrimination ◽  
The Mean

Acculturation and racial discrimination have been independently associated with physical function limitations in immigrant and United States (U.S.)-born populations. This study examined the relationships among acculturation, racial discrimination, and physical function limitations in N = 165 African immigrant older adults using multiple linear regression. The mean age was 62 years ( SD = 8 years), and 61% were female. Older adults who resided in the United States for 10 years or more had more physical function limitations compared with those who resided here for less than 10 years ( b = −2.62, 95% confidence interval [CI] = [–5.01, –0.23]). Compared to lower discrimination, those with high discrimination had more physical function limitations ( b = −2.51, 95% CI = [–4.91, –0.17]), but this was no longer significant after controlling for length of residence and acculturation strategy. Residing in the United States for more than 10 years is associated with poorer physical function. Longitudinal studies with large, diverse samples of African immigrants are needed to confirm these associations.

scholarly journals A Retrospective Analysis of Softball-Related Head and Facial Injuries Treated in United States Emergency Departments, 2013-2017

2019 ◽  
Vol 7 (2) ◽  
pp. 232596711982566 ◽  
Author(s):  
John S. Strickland ◽  
Marie Crandall ◽  
Grant R. Bevill
Keyword(s):  
United States ◽  
Head Injuries ◽  
The United States ◽  
Weighted Estimate ◽  
Body Parts ◽  
Facial Injuries ◽  
Closed Head Injuries ◽  
Closed Head ◽  
The Mean ◽  
Race Ethnicity

Background: Softball is a popular sport played through both competitive and recreational leagues. While head and facial injuries are a known problem occurring from games, little is known about the frequency or mechanisms by which they occur. Purpose: To analyze head/face injury diagnoses and to identify the mechanisms associated with such injuries. Study Design: Descriptive epidemiological study. Methods: A public database was used to query data related to head/facial injuries sustained in softball. Data including age, sex, race/ethnicity, injury diagnosis, affected body parts, disposition, incident location, and narrative descriptions were collected and analyzed. Results: A total of 3324 head and face injuries were documented in the database over the time span of 2013 to 2017, resulting in a nationwide weighted estimate of 121,802 head/face injuries occurring annually. The mean age of the players was 21.5 ± 14.4 years; 72.1% of injured players were female, while 27.9% were male. The most common injury diagnoses were closed head injuries (22.0%), contusions (18.7%), concussions (17.7%), lacerations (17.1%), and fractures (15.1%). The overwhelming majority of injuries involved being struck by a ball (74.3%), followed by colliding with another player (8.3%), colliding with the ground or a fixed object (5.0%), or being struck by a bat (2.8%). For those injuries caused by a struck-by-ball incident, most occurred from defensive play (83.7% were fielders struck by a hit or thrown ball) as opposed to offensive play (12.3% were players hit by a pitch or runners struck by a ball). Although helmet usage was poorly tracked in the database, female players (1.3%) were significantly more likely to have been wearing a helmet at the time of injury than were male players (0.2%) ( P = .002). Conclusion: The present study demonstrates that a large number of head and face injuries occur annually within the United States as a result of softball play. A variety of injuries were observed, with the majority involving defensive players being struck by the ball, which highlights the need for more focus on player safety by stronger adherence to protective headgear usage and player health monitoring.

scholarly journals Stewart's Wilt Reactions of an International Collection of Zea mays Germ Plasm Inoculated with Erwinia stewartii

Plant Disease ◽  
2000 ◽  
Vol 84 (8) ◽  
pp. 901-906 ◽  
Author(s):  
Jerald K. Pataky ◽  
Lindsey J. du Toit ◽  
Noah D. Freeman
Keyword(s):  
United States ◽  
Germ Plasm ◽  
Sweet Corn ◽  
The United States ◽  
River Valley ◽  
Ohio River ◽  
Ohio River Valley ◽  
The World ◽  
The Mean ◽  
Stewart's Wilt

Maize accessions were evaluated in 1997, 1998, and 1999 to identify additional sources of Stewart's wilt resistance and to determine if reactions differed among accessions collected from various regions of the United States and throughout the world. The distributions of Stewart's wilt reactions rated from 1 (no appreciable spread of symptoms) to 9 (dead plants) were relatively similar among groups of accessions from all regions of the world except for those from the Mid-Atlantic/Ohio River Valley region of the United States, the southern United States, and the northeastern United States. The mean and median Stewart's wilt rating for 1,991 accessions evaluated in 1997 was 4. The mean Stewart's wilt rating for 245 accessions collected from the Mid-Atlantic/Ohio River Valley region was 3.1, which was significantly lower than that for accessions from all other regions. The mean rating for accessions from the southern United States was 3.7, which also was lower than mean ratings for accessions from all other regions. Ratings from trials in 1997 and 1998 were highly correlated (r = 0.87) for 292 accessions and 15 sweet corn hybrid checks evaluated in both years. Of 20 accessions rated below 2 in 1997 and 1998, seven were from Virginia, seven were from the Ohio River Valley or central Corn Belt of the United States, four were from the northern or western Corn Belt of the United States, and two were from Spain. Ratings for these accessions ranged from 1.7 to 3.1 in 1999. Ratings ranged from 2.6 to 3.7 for F1 hybrids of these accessions crossed with one of two susceptible sweet corn inbreds, CrseW30 or Crse16, which were rated 5.7 and 5.4, respectively. Based on the reactions of this collection of germ plasm, it appears that high levels of Stewart's wilt resistance are prevalent only among accessions collected from areas where the disease has been endemic for several years, whereas moderate levels of resistance can be found in accessions collected from nearly everywhere in the world.

MMPI-2 Scores of Puerto Rican, Mexican, and U.S. Latino College Students: A Research Note

2000 ◽  
Vol 87 (1) ◽  
pp. 266-268 ◽  
Author(s):  
Jose J. Cabiya ◽  
Denise A. Chavira ◽  
Francisco C. Gomez ◽  
Emilia Lucio ◽  
Jeanett Castellanos ◽  
...  
Keyword(s):  
United States ◽  
College Students ◽  
Puerto Rico ◽  
Standard Deviation ◽  
Puerto Rican ◽  
The United States ◽  
Clinical Scale ◽  
The Mean ◽  
The One ◽  
Scale Data

In this brief report, we present MMPI-2 basic validity and clinical scale data of Latino-descent persons from Puerto Rico ( n = 290), Mexico ( n = 1,920), and the United States ( n = 28). All were administered one of three Spanish translations of the MMPI-2. A review of the mean scores of these respective groups indicates similarities across all scales. Differences among these three groups, with the exception of the Mf scale (which is keyed to sex), were well within the one standard deviation band. More importantly, these findings are promising given the fact that three different translations of the MMPI-2 were applied.

Benchmarks for the Durations of Ambulatory Surgical Procedures in Otolaryngology

2011 ◽  
Vol 120 (11) ◽  
pp. 727-731 ◽  
Author(s):  
Neil Bhattacharyya
Keyword(s):  
United States ◽  
Operating Room ◽  
Surgical Procedures ◽  
Ambulatory Surgery ◽  
Secondary Analysis ◽  
The United States ◽  
Tube Placement ◽  
The Mean ◽  
Room Time ◽  
Ambulatory Procedures

Objectives: I undertook to determine benchmarks and variability for the surgical times associated with ambulatory otolaryngological procedures in the United States. Methods: I examined the 2006 release of the National Survey of Ambulatory Surgery and extracted all cases of otolaryngological surgery in which one, and only one, otolaryngological procedure was performed. The mean surgical times and operating room times were determined for each procedure that met reliability criteria for their estimates. A secondary analysis was computed for tonsillectomy and for tonsillectomy plus adenoidectomy according to a patient age of greater than 12 years. Results: An estimated 1.68 ± 0.23 million otolaryngological procedures were analyzed as solitary procedures, including 507,000 cases of myringotomy with ventilation tube placement, 136,000 cases of tonsillectomy, and 429,000 cases of tonsillectomy plus adenoidectomy. The mean (±SE) surgical times were 8.0 ± 0.5, 23.9 ± 1.8, and 20.3 ± 0.8 minutes, respectively. The total operating room times were 17.6 ± 0.9, 48.2 ± 2.0, and 40.7 ± 1.1 minutes, respectively. Septoplasty with turbinectomy was the most common rhinologic procedure performed (48,000 cases analyzed) and had surgical and operating room times of 49.6 ± 4.78 and 79.8 ± 5.8 minutes, respectively. The surgical times for tonsillectomy and tonsillectomy plus adenoidectomy did not differ significantly in magnitude according to standard age cutoffs, although the operating room time was slightly (11.7 minutes) longer for tonsillectomy in patients more than 12 years of age (p = 0.034). Conclusions: The surgical times for the performance of the most common otolaryngological ambulatory procedures are remarkably consistent in the United States. Given the volume and consistency of these surgical procedures, they are ideal candidates for studies of cost and efficiency.

scholarly journals Hodgkin’s Disease

Blood ◽  
1955 ◽  
Vol 10 (12) ◽  
pp. 1214-1227 ◽  
Author(s):  
MICHAEL B. SHIMKIN
Keyword(s):  
United States ◽  
Sex Ratio ◽  
Hodgkin's Disease ◽  
Death Rate ◽  
Hodgkin’S Disease ◽  
The United States ◽  
Age At Death ◽  
Male Predominance ◽  
Female Sex ◽  
The Mean

Abstract Mortality from Hodgkin’s disease in the United States during the period 1921 through 1951 was analyzed with respect to race, sex and age incidence and distribution. The findings were compared with those reported for leukemia. The recorded death rate from Hodgkin’s disease rose from 6.9 in 1921 to 17.0 per million in 1951. During this period, the death rate from leukemia rose from 14 to 61 per million. The death rate among males is higher than among females for both diseases; the male predominance is more marked in Hodgkin’s disease than in leukemia. The rate is higher among whites than non-whites for both diseases; the white predominance is more marked in leukemia than in Hodgkin’s disease. There is no peak in rate during childhood for Hodgkin’s disease as there is for leukemia, and the increase in rate with age is much less steep for Hodgkin’s disease than for leukemia. The mean age at death of adults dying from Hodgkin’s disease and from leukemia increased by 3.5 and 8.0 years, respectively, between 1925 and 1950. The male-female sex ratio for Hodgkin’s disease decreased slightly, and increased slightly for leukemia between 1925 and 1950.

scholarly journals Forecasting the Maintenance of Mesoscale Convective Systems Crossing the Appalachian Mountains

2010 ◽  
Vol 25 (4) ◽  
pp. 1179-1195 ◽  
Author(s):  
Casey E. Letkewicz ◽  
Matthew D. Parker
Keyword(s):  
Appalachian Mountains ◽  
Severe Weather ◽  
Mesoscale Convective Systems ◽  
Radiosonde Data ◽  
Eastern United States ◽  
Unique Problem ◽  
Convective Systems ◽  
Barrier Analysis ◽  
Mesoscale Convective ◽  
The Mean

Abstract Forecasting the maintenance of mesoscale convective systems (MCSs) is a unique problem in the eastern United States due to the influence of the Appalachian Mountains. At times these systems are able to traverse the terrain and produce severe weather in the lee, while at other times they instead dissipate upon encountering the mountains. To differentiate between crossing and noncrossing MCS environments, 20 crossing and 20 noncrossing MCS cases were examined. The cases were largely similar in terms of their 500-hPa patterns, MCS archetypes, and orientations with respect to the barrier. Analysis of radiosonde data, however, revealed that the environment east of the mountains discriminated between case types very well. The thermodynamic and kinematic variables that had the most discriminatory power included those associated with instability, several different bulk shear vector magnitudes, and also the mean tropospheric wind. Crossing cases were characterized by higher instability, which was found to be partially attributable to the diurnal cycle. However, these cases also tended to occur in environments with weaker shear and a smaller mean wind. The potential reasons for these results, and their forecasting implications, are discussed.

What Is the Price and Claimed Efficacy of Platelet-Rich Plasma Injections for the Treatment of Knee Osteoarthritis in the United States?

2018 ◽  
Vol 32 (09) ◽  
pp. 879-885 ◽  
Author(s):  
Nicolas S. Piuzzi ◽  
Mitchell Ng ◽  
Ariel Kantor ◽  
Kenneth Ng ◽  
Stephanie Kha ◽  
...  
Keyword(s):  
United States ◽  
Standard Deviation ◽  
Knee Osteoarthritis ◽  
Clinical Efficacy ◽  
Health Care Providers ◽  
Platelet Rich Plasma ◽  
The United States ◽  
Care Providers ◽  
Knee Oa ◽  
The Mean

AbstractPlatelet-rich plasma (PRP) injections are often used for the treatment of knee osteoarthritis (OA), despite clinical value and cost-effectiveness not being definitely established. PRP injections are considered as a potential means of reducing pain and improving function in patients with knee OA, in the hope of delaying or avoiding the need for surgical intervention. Centers that offer PRP injections usually charge patients out of pocket and directly market services. Therefore, the purpose of this study was to quantify the current (1) prices and (2) marketed clinical efficacy of autologous PRP injections for knee OA. A prospective cross-sectional study was performed based on 286 centers identified in the United States offering PRP injections for knee OA. A total of 179 (73.4%) centers were successfully contacted via e-mail or phone, using a simulated 52-year-old male patient with knee OA. Scripted questions were asked by the simulated patient to determine the current marketed prices and clinical efficacy, either reported as “good results” or “symptomatic improvement,” claimed by each treating center. The mean price for a single unilateral knee same-day PRP injection was $714 with a standard deviation of $144 (95% confidence interval [CI]: $691–737, n = 153). The mean claim of clinical efficacy was 76% with a standard deviation of 11% (95% CI: 73.5–78.3%, n = 84). Out of the 84 clinics, 10 claimed “90 to 100% efficacy,” 27 claimed “80 to 90%,” 29 claimed “70 to 80%,” 9 claimed “60 to 70%,” 8 claimed “50 to 60%,” and 1 claimed “40 to 60%.” These findings provide a unique perspective on the PRP market for the treatment of knee OA that is valuable to physicians and health care providers in providing better education to patients on the associated costs and purported clinical benefits of PRP injections.

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