857 research outputs found
The Demographics of Non-motor Vehicle Associated Railway Injuries Seen at Trauma Centers in the United States 2007 - 2014
Introduction
The majority of railway injury studies are limited by small sample size, restricted to a small geographical distribution, or located outside the United States (US). The aim of our study was to assess the demographic patterns associated with non-motor vehicle railway injuries in the US using a national trauma center database.
Materials and Methods
Data from the National Trauma Data Bank data from 2007 - 2014 were used; 3,506 patients were identified. For all statistical analyses, a p-value < 0.05 was considered significant.
Results
The patients were 81% male with an average age of 38.6 + 17.1 years and an Injury Severity Score (ISS) of 16.8 + 13.8. Males compared to females were younger (37.7 vs 42.5 years, p = 0.000002), had greater length of stays (12.7 vs 9.8 days, p = 0.000006), and higher ISS scores (17.1 vs 15.4, p = 0.0007). The geographic distribution within the US was most common in the South (32.0%) and least in the Northeast (18.9%). The racial composition was 67.5% White, 19.1% Black, 11.5% Hispanic/Latino, and 1.9% others. The most common mechanisms of injury were hitting/colliding with rolling stock (38.6%), followed by a fall in or from a train (19.5%), and collision with an object (13.5%). The majority of patients were pedestrians or passengers (68.5%); employees accounted for 12.5%. Although the majority were pedestrian/passengers for all regions, the Midwest had a greater proportion of employees (22.0%) compared to the other regions (7.8% to 12.2%) (p < 10-6), and thus injuries were more commonly work-related (24.6% vs 6.7% - 13.7%, p < 10-6). Work-related injuries were less severe (ISS 11.2 vs 17.3 - p < 10-6) and more commonly occurred due to a fall (32.8% vs 17.9%, p < 10-6). Alcohol and/or drug involvement was present in 40.7% and was less in those with work-related injuries (2.2%). Overall mortality was 6.4% and was less in those having a work-related injury (2.0 vs 6.6% p = 0.000004).
Conclusion
For non-motor vehicle USA railway injuries, the average age was 38.5 years; 80.6% were male. The injuries were least common in the Northeast and most common in the South. Racial distribution mirrored that of the US population. Alcohol involvement was present in 29%, lower than in previous studies. Mortality was 6.4%, also lower than previously reported
Disparities in Child and Adolescent Mental Health and Mental Health Services in the U.S.
This is one of a series of five papers outlining the particular domains and dimensions of inequality where new research may yield a better understanding of responses to this growing issue.Mental health is recognized as a central determinant of individual well-being, family relationships, and engagement in society, yet there are considerable variations in mental health and mental health care according to race and ethnicity among youth in the U.S.In their report, Margarita Alegría and colleagues investigate disparities in mental health and mental health services for minority youth. Taking a developmental perspective, the authors explore four areas that may give rise to inequalities in mental health outcomes, highlight specific protective factors and barriers to care, and, finally, outline an agenda for future research
Supercurrent through grain boundaries in the presence of strong correlations
Strong correlations are known to severely reduce the mobility of charge
carriers near half-filling and thus have an important influence on the current
carrying properties of grain boundaries in the high- cuprates. In this
work we present an extension of the Gutzwiller projection approach to treat
electronic correlations below as well as above half-filling consistently. We
apply this method to investigate the critical current through grain boundaries
with a wide range of misalignment angles for electron- and hole-doped systems.
For the latter excellent agreement with experimental data is found. We further
provide a detailed comparison to an analogous weak-coupling evaluation.Comment: 4 pages, 3 figure
Seasonal Variation in Slipped Capital Femoral Epiphysis: New Findings Using a National Children’s Hospital Database
Background: Slipped capital femoral epiphysis (SCFE) demonstrates seasonal variation in certain latitudes but not others. Is such variation influenced by temperature differences, sunlight exposure and subsequent vitamin D production, or other climate variables? It was the purpose of this study to further investigate the seasonal variation in month of presentation for SCFE.
Methods: Data for this study originated from the Pediatric Hospital Information System for all children with a diagnosis of SCFE from January 1, 2004 through December 31, 2014. From this database the patient’s sex, ethnicity, hospital location, and month of presentation was determined. Only those patients treated primarily for SCFE were included. Geographic and climate data [latitude, average annual temperature, precipitation, climate type (Köppen-Geiger and Liss), horticultural plant zone hardiness, and sunlight exposure] for each of the 49 Pediatric Hospital Information System hospitals was determined. Seasonal variation was analyzed using cosinor analysis. A P<0.05 was considered statistically significant.
Results: There were 10,350 cases of SCFE with an overall peak presentation in mid August. For those living at a latitude of >35-degree N there was single peak, a less prominent double peak for those 31- to 35-degree N, and no variation for those <31-degree N. As the average annual temperature increased there was less seasonal variability. Humid, temperate and cold winter climates demonstrated seasonal variation, whereas other climate types did not. Those living in areas having <2500 hours of sunlight per year demonstrated seasonal variation. Further, areas having a photovoltaic solar production potential <5.0 kWh/m2/d also demonstrated seasonal variation.
Conclusions: We discovered new seasonal variation findings regarding SCFE. These are a double peak pattern for those between 31- and 35-degree N latitude; less variability as the average annual temperature increases; and sunlight exposure correlates with seasonal variability. Potential explanations are a rachitic state due to seasonal variation in vitamin D production, and seasonal variation in physeal growth and strength. These new findings will require further investigation
A Bibliometric Study of Authorship and Collaboration Trends Over the Past 30 Years in Four Major Musculoskeletal Science Journals
This study explored changes in bibliometric variables over the last 30 years for four major musculoskeletal science journals (BONE®), Calcified Tissue International® (CTI®), Journal of Bone and Mineral Research® (JBMR®), and Journal of Orthopaedic Research® (JOR®), with a specific focus on author gender. Bibliometric data were collected for all manuscripts in 1985 (BONE®, CTI®, JOR®), 1986 (JBMR®), 1995, 2005, and 2015; 2776 manuscripts met inclusion criteria. Manuscripts from Europe were more often published in BONE® or CTI®, while those from North America in JBMR® or JOR®. All journals demonstrated an increase over time in the number of authors (3.67–7.3), number of countries (1.1–1.4), number of institutions (1.4–3.1), and number of references (25.1–45.4). The number of manuscript pages increased (6.6–8.9) except for JOR® which showed a decline. CTI® had the lowest number of authors (4.9 vs. 5.6–6.8). There was a change in the corresponding author position from first to last for all journals; this change was highest for CTI® (35%) and lowest for BONE® (14.0%). All journals demonstrated an increase over time in female authors; however, CTI® was the highest amongst these four journals. The percentage of female first authors rose from 24.6 to 44.3% (CTI® 29.1–52.3%). The percentage of corresponding female authors rose from 17.5 to 33.6% (CTI® 22.9–40.0%). The proportion of female authors is increasing, likely reflecting the increasing number of women obtaining doctorates in science, medicine, and engineering
Seasonal variation in adult hip disease secondary to osteoarthritis and developmental dysplasia of the hip
AIM:
To determine if there was a seasonal variation in adults undergoing total hip arthroplasty for end stage hip disease due to osteoarthritis (OA) or sequelae of developmental dysplasia of the hip (DDH).
METHODS:
The total hip registry from the author's institution for the years 1969 to 2013 was reviewed. The month of birth, age, gender, and ethnicity was recorded. Differences between number of births observed and expected in the winter months (October through February) and non-winter mo (March through September) were analyzed with the χ2 test. Detailed temporal variation was mathematically assessed using cosinor analysis.
RESULTS:
There were 7792 OA patients and 60 DDH patients who underwent total hip arthroplasty. There were more births than expected in the winter months for both the DDH (P < 0.0001) and OA (P = 0.0052) groups. Cosinor analyses demonstrated a peak date of birth on 1st October.
CONCLUSION:
These data demonstrate an increased prevalence of DDH and OA in those patients born in winter
Crossover from hc/e to hc/2e current oscillations in rings of s-wave superconductors
We analyze the crossover from an hc/e-periodicity of the persistent current
in flux threaded clean metallic rings towards an hc/2e-flux periodicity of the
supercurrent upon entering the superconducting state. On the basis of a model
calculation for a one-dimensional ring we identify the underlying mechanism,
which balances the hc/e versus the hc/2e periodic components of the current
density. When the ring circumference exceeds the coherence length of the
superconductor, the flux dependence is strictly hc/2e periodic. Further, we
develop a multi-channel model which reduces the Bogoliubov - de Gennes
equations to a one-dimensional differential equation for the radial component
of the wave function. The discretization of this differential equation
introduces transverse channels, whose number scales with the thickness of the
ring. The periodicity crossover is analyzed close the critical temperature
Total hip arthroplasty in young adults, with focus on Perthes' disease and slipped capital femoral epiphysis: Follow-up of 540 subjects reported to the Norwegian Arthroplasty Register during 1987–2007
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