Magnetic properties of CuxMn1 x 3[Cr CN 6]2.zH2O complexes

Magnetization measurements were performed on the CuxMn1 x 3[Cr CN 6]2.zH2O molecule based magnets where x 0 0, 0.2, 0.25, 0.3, 0.35 0.4, 0.6, 0.8 and 1.0. Both the Curie temperature and saturated magnetization at first decrease with increasing value of x reaching the minimal value of TC 49 7 K and 0 17 B for x 0 2 and then increase with substitution. The pronounced hysteretic behavior between zero field cooled and field cooled regimes was observed for all samples. Magnetization changes the sign of magnetic polarization in zero field cooled magnetization curve at the compensation temperature Tcomp 16 K for sample with x 0 4. Our results indicate that the system behaves as mixed ferri ferromagnetic syste

Safe-Play Knowledge, Aggression, and Head-Impact Biomechanics in Adolescent Ice Hockey Players

Addressing safe-play knowledge and player aggression could potentially improve ice hockey sport safety

An Assessment of High School Athletes’ and Coaches’ Knowledge, Attitudes, and Behaviors of Concerning Concussion

Cerebral concussions are one of the most perplexing sports injuries to identify and manage. As a result, many of these injuries go unreported and untreated. Few studies to date have addressed the behavior of concussion reporting, specifically among young athletes. The overall purpose of this dissertation was to assess knowledge, attitudes, intentions, and behaviors concerning concussion using a pre-validated survey instrument. A convenience sample of 25 high schools participated in the study. Meetings were held at each school to explain the study and distribute the survey instruments to coaches and athletes. The Theory of Reasoned Action and Planned Behavior guided the direction of the study. A sample of 167 high school athletes (football, soccer, lacrosse, cheerleading) and 59 high school coaches completed the pre-validated survey instrument during the 2009-2010 school year. There was major under-reporting of concussive events with respondents indicating only 40% of concussion events and 13% of bell ringer events indicated had been reported. The major factors associated with increased reporting of recalled concussion/bell ringer event reporting and participating with concussions signs/symptoms in the sample of athletes included: 1) increased athlete concussion knowledge and attitude, 2) increased intention to report concussions, 3) increased positive influence form social referents, 4) decreased number of previous concussive injuries. No association was observed between school level coach knowledge/attitude scores and athlete knowledge/attitude scores. This study illustrates the multi-factorial issues concerning concussion in young athletes. The factors listed above could serve as the foundation for a multi-level intervention designed to improve concussion reporting and to decrease participation while experiencing signs and symptoms from concussion. The data obtained from this study illustrates necessary targets of future educational and behavioral interventions concerning concussion among high school athletes

Superconductivity in the YIr2Si2 and LaIr2Si2 Polymorphs

We report on existence of superconductivity in YIr2Si2 and LaIr2Si2 compounds in relation to crystal structure. The two compounds crystallize in two structural polymorphs, both tetragonal. The high temperature polymorph (HTP) adopts the CaBe2Ge2-structure type (space group P4/nmm) while the low temperature polymorph (LTP) is of the ThCr2Si2 type (I4/mmm). By studying polycrystals prepared by arc melting we have observed that the rapidly cooled samples retain the HTP even at room temperature (RT) and below. Annealing such samples at 900C followed by slow cooling to RT provides the LTP. Both, the HTP and LTP were subsequently studied with respect to magnetism and superconductivity by electrical resistivity, magnetization, AC susceptibility and specific heat measurements. The HTP and LTP of both compounds respectively, behave as Pauli paramagnets. Superconductivity has been found exclusively in the HTP of both compounds below Tsc (= 2.52 K in YIr2Si2 and 1.24 K in LaIr2Si2). The relations of magnetism and superconductivity with the electronic and crystal structure are discussed with comparing experimental data with the results of first principles electronic structure calculations

Association Between Sensation-Seeking Behaviors and Concussion-Related Knowledge, Attitudes, Perceived Norms, and Care-Seeking Behaviors among Collegiate Student-Athletes

There are limited data connecting personality and behavioral tendencies and traits related to concussion care-seeking/disclosure behaviors and minimal research exists surrounding the relationship between risky behaviors, sensation-seeking, and concussion-related outcomes. This study examined the association between sensation-seeking and a student-athlete’s concussion-related knowledge, attitudes, perceived social norms, and concussion care-seeking/disclosure behaviors (intention to disclose concussion symptoms, perceived control over symptom disclosure, self-removal from play due to concussion symptoms, continued play with concussion symptoms, and disclosure of all concussions at the time of injury). The current study utilized a retrospective cohort of collegiate student-athletes at a single National Collegiate Athletic Association Division I institution. Separate multivariable linear regression models estimating mean differences (MD) and 95% Confidence Intervals (CI) estimated the association between sensation-seeking and concussion knowledge, concussion attitudes, and perceived social norms. Separate multivariable binomial regression models estimating adjusted prevalence ratios (PR) and 95%CI estimated the association between sensation-seeking and intention to disclose concussion symptoms, perceived control over symptom disclosure, self-removal from play due to concussion symptoms, continued play with concussion symptoms, and disclosure of all concussions at the time of injury. All models were adjusted for sex, sport participation, and concussion history. Higher sensation-seeking was significantly associated with less favorable concussion attitudes (adjusted MD = -1.93; 95%CI = -3.04,-0.83), less favorable perceived social norms surrounding concussion (adjusted MD = -1.39; 95%CI = -2.06,-0.72), and continuing to play while experiencing concussion symptoms (adjusted PR = 1.50; 95%CI = 1.10, 2.06). Student-athletes with increased sensation-seeking could be at risk for failing to disclose a concussion, decreasing athlete safety and resulting in less optimal care post-injury. Results will inform future theory-based concussion education programs which consider behavioral tendencies and traits as well as sport culture to promote concussion care-seeking/disclosure and individualized interventions based on risky behavior engagement

Epidemiology of Skin Infections in Men's Wrestling: Analysis of 2009–2010 Through 2013–2014 National Collegiate Athletic Association Surveillance Data

CONTEXT: Our knowledge of the current epidemiology of skin infections among wrestlers is limited. OBJECTIVE: To analyze and report the epidemiology of skin infections among National Collegiate Athletic Association (NCAA) men's wrestling student-athletes during the 2009-2010 through 2013-2014 academic years. DESIGN: Descriptive epidemiology study. SETTING: Aggregate skin infection and exposure data collected by the NCAA Injury Surveillance Program. PATIENTS OR OTHER PARTICIPANTS: Collegiate men's wrestling student-athletes. MAIN OUTCOME MEASURE(S): All viral, bacterial, or fungal skin infections reported by athletic trainers at 17 NCAA programs were analyzed, providing 35 team-seasons of data. Skin infection rates per 10 000 athlete-exposures (AEs), rate ratios, skin infection proportions, and skin infection proportion ratios were calculated. RESULTS: The athletic trainers reported 112 skin infections contracted by 87 student-athletes across 78 720 AEs. The overall skin infection rate was 14.23/10 000 AEs (95% confidence interval [CI] = 11.59, 16.86). Of the skin infections identified, 22.3% (n = 25) were recurrent skin infections. Most skin infections (65.2%) were attributable to 5 team-seasons (range, 11-19 infections). Most skin infections occurred during the regular season (n = 76, 67.9%), were identified during practice (n = 100, 89.3%), and resulted in ≥24 hours' time loss (n = 83, 74.1%). The rate for viral skin infections was 1.72 times the rate for bacterial skin infections (95% CI = 1.09, 2.72) and 2.08 times the rate for fungal skin infections (95% CI = 1.28, 3.39). Fungal skin infections more often resulted in time loss <24 hours compared with all other skin infections (75.0% versus 12.5%; infection proportion ratio = 6.00; 95% CI = 3.30, 10.92). CONCLUSIONS: Our findings highlight the contagiousness of skin infections and suggest that skin infection rates may be attributable to high incidences among particular teams

Motivations Associated With Nondisclosure of Self-Reported Concussions in Former Collegiate Athletes

Previous studies examining non-disclosure among athletes in various settings have found substantial proportions of athletes with undisclosed concussions. Substantial gaps exist in our understanding of the factors influencing athletes’ disclosure of sports-related concussions

Age-Related Differences and Reliability on Computerized and Paper-and-Pencil Neurocognitive Assessment Batteries

Neurocognitive testing is a recommended component in a concussion assessment. Clinicians should be aware of age and practice effects on these measures to ensure appropriate understanding of results

Dehydration and Performance on Clinical Concussion Measures in Collegiate Wrestlers

The effects of dehydration induced by wrestling-related weight-cutting tactics on clinical concussion outcomes, such as neurocognitive function, balance performance, and symptoms, have not been adequately studied