Extremity wounds and fractures traditionally comprise the majority of traumatic injuries in US armed conflicts. Little has been published regarding the extremity wounding patterns and fracture ...distribution in the current conflicts in Iraq and Afghanistan. The intent of this study was to describe the distribution of extremity fractures during this current conflict.
Descriptive epidemiologic study.
The Joint Theater Trauma Registry was queried for all US service members receiving treatment for wounds (ICD-9 codes 800-960) sustained in Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) from October 2001 through January 2005. Returned-to-duty and nonbattle injuries were excluded. Wounds were classified according to region and type. Extremity wounds were analyzed in detail and compared to published results from previous conflicts.
A total of 1281 soldiers sustained 3575 extremity combat wounds. Fifty-three percent of these were penetrating soft-tissue wounds and 26% were fractures. Of the 915 fractures, 758 (82%) were open fractures. The 915 fractures were evenly distributed between the upper (461, 50%) and lower extremities (454, 50%). The most common fracture in the upper extremity was in the hand (36%) and in the lower extremity was the tibia and fibula (48%). Explosive munitions accounted for 75% of the mechanisms of injury.
The burden of wounds sustained in OIF/OEF is extremity injuries, specifically soft-tissue wounds and fractures. These results are similar to the reported casualties from previous wars.
Bed bug infestations in an urban environment Hwang, Stephen W; Svoboda, Tomislav J; De Jong, Iain J ...
Emerging infectious diseases,
04/2005, Letnik:
11, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Until recently, bed bugs have been considered uncommon in the industrialized world. This study determined the extent of reemerging bed bug infestations in homeless shelters and other locations in ...Toronto, Canada. Toronto Public Health documented complaints of bed bug infestations from 46 locations in 2003, most commonly apartments (63%), shelters (15%), and rooming houses (11%). Pest control operators in Toronto (N = 34) reported treating bed bug infestations at 847 locations in 2003, most commonly single-family dwellings (70%), apartments (18%), and shelters (8%). Bed bug infestations were reported at 20 (31%) of 65 homeless shelters. At 1 affected shelter, 4% of residents reported having bed bug bites. Bed bug infestations can have an adverse effect on health and quality of life in the general population, particularly among homeless persons living in shelters.
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•Cycled permeation experiments are evaluated with physically sound diffusion models.•Use of Armco iron eliminates the role of defects due to alloying and precipitation.•Hydrogen trap ...sites are identified and their densities and energies are determined.•Fully parametrized diffusion and trapping model is provided.•Microstructure-property relations for trap density evolution are presented.
Understanding hydrogen embrittlement in steels requires research in hydrogen diffusion and trapping at microstructural defects. The present paper deals with hydrogen permeation and trapping at defects in the base material, Armco iron, eliminating effects coupled with alloying and precipitation. Cycled permeation curves are recorded and evaluated by using sound diffusion models to identify hydrogen trap sites as dislocations, grain boundaries and vacancies and assign their trapping energies. Furthermore, trap densities are evaluated and used together with the trapping energies as parameters in an adapted diffusion equation for hydrogen, interpreting the experiments significantly better than simple use of classical Fick’s laws.
In this paper, we report the results of an X-ray monitoring campaign on the heavily obscured Seyfert galaxy, Markarian 3, carried out between the fall of 2014 and the spring of 2015 with NuSTAR, ...Suzaku and XMMNewton. The hard X-ray spectrum of Markarian 3 is variable on all the time-scales probed by our campaign, down to a few days. The observed continuum variability is due to an intrinsically variable primary continuum seen in transmission through a large, but still Compton-thin column density (N(sub H) approx. 0.8-1.1 x 10(exp 24)/sq cm). If arranged in a spherical-toroidal geometry, the Compton scattering matter has an opening angle approx. 66deg, and is seen at a grazing angle through its upper rim (inclination angle approx. 70deg). We report a possible occultation event during the 2014 campaign. If the torus is constituted by a system of clouds sharing the same column density, this event allows us to constrain their number (17 +/- 5) and individual column density, approx. (4.9 +/- 1.5) x 10(exp 22)/ sq cm. The comparison of IR and X-ray spectroscopic results with state-of-the art torus models suggests that at least two-thirds of the X-ray obscuring gas volume might be located within the dust sublimation radius. We report also the discovery of an ionized absorber, characterized by variable resonant absorption lines due to He- and H-like iron. This discovery lends support to the idea that moderate column density absorbers could be due to clouds evaporated at the outer surface of the torus, possibly accelerated by the radiation pressure due to the central AGN emission leaking through the patchy absorber.
Infanticide occurs in a variety of animal species and infanticide risk has large implications for the evolution of behavior. Further, the sex hypothesis of sexual segregation predicts that for ...species in which infanticide occurs, females with dependent young will avoid males to reduce risk of sexually-selected infanticide. Infanticide risk-avoidance behavior has been studied primarily in social species, but also occurs in some solitary species. We used generalized linear mixed models to determine if space use and movements of female American black bears (Ursus americanus) during the breeding season were consistent with the sex hypothesis of sexual segregation in the Upper Peninsula of Michigan, USA. Space use and movements of female black bears (n = 16) were not consistent with avoidance behavior to reduce sexually-selected infanticide risk. Females with cubs occupied core areas (mean = 4.64 km2, standard error SE = 1.28) and home ranges (mean = 19.46 km2, SE = 5.10) of similar size to females without cubs (core area mean = 4.11 km2, SE = 0.59; home range mean = 16.07 km2, SE = 2.26), and those core areas and home ranges were not in areas with lesser relative probability of male use. Additionally, females with cubs did not reduce movements during times of day when male movements were greatest. As female bears do avoid potentially infanticidal males in populations with greater levels of infanticide, female black bears may exhibit variation in avoidance behavior based on the occurrence of infanticide.
Little is known about the risk factors for glenohumeral joint instability. We hypothesized that a prior history of instability would be a significant risk factor for subsequent injury.
We conducted a ...prospective cohort study over a four-year period within a high-risk group of young athletes to address the research hypothesis. Subjects were freshmen entering the U.S. Military Academy in June of 2006. Part of the baseline assessment included documenting a prior history of glenohumeral instability on entry into the study. All subjects were followed for subsequent glenohumeral joint instability events until graduation in May of 2010. The primary outcome of interest in this study was time to glenohumeral instability event during the follow-up period. We examined injury outcomes, looking for any instability, anterior instability, and posterior instability events. Cox proportional-hazards regression models were used to analyze the data.
Among the 714 subjects, eight shoulders were excluded from the analyses due to prior surgical stabilization, leaving 1420 shoulders, of which 126 had a self-reported prior history of instability. There were forty-six (thirty-nine anterior and seven posterior) acute instability events documented in the cohort during the follow-up period. Subjects with a prior history of instability were over five times (p < 0.001) more likely to sustain an acute (anterior or posterior) instability event during the follow-up period. Subjects with a history of instability were also 5.6 times (p < 0.001) more likely to experience a subsequent anterior instability event and 4.6 times (p = 0.068) more likely to experience a posterior instability event during follow-up. Similar results were observed in multivariable models after controlling for the influence of demographic and baseline physical examination findings.
Despite meeting the rigorous physical induction standards for military service, subjects with a prior history of glenohumeral joint instability were approximately five times more likely to experience a subsequent instability event, regardless of direction, within this high-risk athletic population.
Magnetic techniques are the cornerstone of material manipulation and over the last 30 years these methods have undergone dramatic developments. Advantages of magnetic methods of material treatment ...are numerous and the spectrum of applications of this technique is formidable. Numerous technological milestones and key drivers of innovations in magnetic separation have resulted in a wide range of magnetic techniques that are available for application in various industries. This paper reviews the current status of magnetic separation and outlines the future trends in research and development.
Background:
A medial collateral ligament (MCL) knee sprain is a prevalent injury in athletic populations that may result in significant time lost to injury. Remarkably little is known of the ...epidemiology of this injury.
Purpose:
To define the incidence of MCL tears and to determine the demographic and athletic risk factors.
Study Design:
Descriptive epidemiological study.
Methods:
A longitudinal cohort study was performed to examine the epidemiology of isolated MCL sprains at the United States Military Academy (USMA) between 2005 and 2009. Charts and radiographic studies were reviewed by an independent orthopaedic surgeon to identify all new isolated MCL sprains resulting in time lost to sport and activity that occurred within the study period. Incidence rates (IRs) with 95% confidence intervals (CIs) were calculated per 1000 person-years at risk and by sex, sport, and level of competition. The IR per 1000 athlete-exposures (AEs) was also determined. Incidence rate ratios (IRRs) and respective 95% CIs were calculated between male and female students, intercollegiate and intramural athletes, and male and female intercollegiate athletes involved in selected sports. Chi-square and Poisson regression analyses were used to examine the relationship between the variables of interest and the incidence of MCL sprains, with statistical significance set at P < .05.
Results:
A total of 128 cadets sustained isolated MCL injuries during 17,606 student person-years from 2005 to 2009. This resulted in an IR of approximately 7.3 per 1000 person-years. Of the 128 injuries, 114 were in male athletes (89%) and 14 were in female athletes (11%). Male cadets had a 44% higher IR than did female cadets (7.60 vs 5.36, respectively), although this was not significant (P = .212). Of 5820 at-risk intercollegiate athletes, 59 (53 male, 6 female) sustained an isolated MCL sprain during 528,523 (407,475 male, 121,048 female) AEs for an overall IR of 10.14 per 1000 person-years and 0.11 per 1000 AEs. The IRR of MCL sprains of men compared with women involved in intercollegiate athletics was 2.87 (95% CI, 1.24-8.18) per 1000 person-years and 2.62 (95% CI, 1.13-7.47) per 1000 AEs. Of 21,805 at-risk intramural athletes, with quarterly participation, 16 (all male) sustained isolated MCL injuries during 225,683 AEs for an overall IR of 0.07 per 1000 AEs. The IRs of MCL injuries of intercollegiate and intramural athletes did not differ significantly. In intercollegiate sports, wrestling (0.57), judo (0.36), hockey (0.34), and rugby (men’s, 0.22; women’s, 0.23) had the highest IRs per 1000 AEs. When examining men’s intercollegiate athletics, the IRRs of wrestling (13.41; 95% CI, 1.80-595.27) and hockey (8.12; 95% CI, 0.91-384.16) were significantly higher compared with that of lacrosse. Among women’s intercollegiate sports as well as intramural sports, there were no significant differences in IRs. A median of 16 days was lost to injury, with 2407 total days lost for all injuries. Grade 1 MCL injuries lost a median of 13.5 days, while higher grade injuries lost a median of 29 days.
Conclusion:
Medial collateral ligament injuries are relatively common in athletic cohorts. The most injurious sports are contact sports such as wrestling, hockey, judo, and rugby. Male athletes are at a greater risk than female athletes. Intercollegiate athletes are at a greater risk than intramural athletes. The average amount of time lost per injury was 23.2 days, with greater time lost with higher grade sprains than grade 1 sprains.
•A modelling study for diffusion of hydrogen with traps is presented.•Hydrogen permeation cannot be described by a constant effective diffusivity.•Diffusivity depends widely on hydrogen concentration ...and traps.•Charging and discharging process show asymmetry.
Hydrogen permeation (diffusion) is strongly influenced by the local hydrogen concentration and by the density and depth of traps. Consequently hydrogen diffusion cannot be described by a constant effective diffusivity as suggested in standards and several papers.
A modelling study for diffusion of hydrogen in metals with traps is presented. Simulations are performed for a charging and discharging process, showing a remarkable asymmetry. The actual chemical diffusivity ranges over several orders of magnitude depending on the hydrogen concentration as well as the density and depth of traps. Consequently, the concept of effective diffusivity outlined in standards and many publications fails.
Objective
The association between knee injury and knee osteoarthritis (OA) is understudied relative to its importance, particularly in younger populations. This study was undertaken to examine the ...association of knee injury with radiographic features of knee OA in military officers, who have a physically demanding profession and high rates of knee injury.
Methods
Participants were recruited in 2015–2017 from an existing program that enrolled 6,452 military officers during 2004–2009. Officers with a history of knee ligament or meniscal injuries (n = 117 via medical record review) were compared to officers with no history of knee injury (n = 143). Bilateral posteroanterior knee radiographs were obtained using a standardized fixed‐flexion positioning frame. All images were read for Kellgren/Lawrence (K/L) grade, osteophyte (OST), and joint space narrowing (JSN) scores. Data were analyzed using linear‐risk regression models with generalized estimating equations.
Results
Injured and noninjured participants were similar (mean age 28 years, mean body mass index 25 kg/m2, ~40% female). The mean time from first knee injury to imaging among injured participants was 9.2 years. Compared with noninjured knees, greater prevalence of radiographic OA (K/L grade ≥ 2), OST (grade ≥ 1), and JSN (grade ≥ 1) was observed among injured knees, with prevalence differences of +16% (95% confidence interval 95% CI 10%, 22%), +29% (95% CI 20%, 38%), and + 17% (95% CI 10%, 24%), respectively. Approximately 1 in 6 officers with prior knee injury progressed to radiographic OA by age 30 years.
Conclusion
At the midpoint of a projected 20‐year military career, officers with a history of traumatic knee injury have a markedly increased prevalence of knee radiographic OA compared to officers without injury.