Entanglement fidelity for electron-electron interaction in strongly coupled semiclassical plasma and under external fields

This paper presents the effects of AB-flux field and electric field on electron-electron interaction, encircled by a strongly coupled semiclassical plasma. We found that weak external fields are required to perpetuate a low-energy elastic electron-electron interaction in a strongly coupled semiclassical plasma. The entanglement fidelity in the interaction process has been examined. We have used partial wave analysis to derive the entanglement fidelity. We found that for a weak electric field, the fidelity ratio for electron-electron interaction increase as projectile energy increase but remains constant or almost zero for a strong electric field. Our results provide an invaluable information on how the efficiency of entanglement fidelity for a low-energy elastic electron-electron interaction in a strongly coupled semiclassical plasma can be influenced by the presence of external fields

Differential Effects of Fatigue on Movement Variability

When individuals perform purposeful actions to fatigue, there is typically a general decline in their movement performance. This study was designed to investigate the effects exercise-induced fatigue has on lower limb kinetics and kinematics during a side-step cutting task. In particular, it was of interest to determine what changes could be seen in mean amplitude and all metrics of signal variability with fatigue. The results of the study revealed that post-fatigue there was an overall decrease in absolute force production as reflected by a decline in mean amplitude and variability (SD) of the ground reaction forces (GRFV and GRFML). A decrease in mean and SD of the knee moments were also observed post-exercise. Interestingly, this trend was not mirrored by similar changes in time-dependent properties of these signals. Instead, there was an increase in the SampEn values (reflecting a more variable, irregular signal) for GRF force profiles, knee kinematics and moments following the exercise-induced fatigue. These results illustrate that fatigue can have differential effects on movement variability, resulting in a both an increase and decrease in movement variability, depending on the variable selected. Thus, the impact of fatigue is not simply restricted to a decline in force producing capacity of the system but more importantly it demonstrates that the ability of the person to perform a smooth and controlled action is limited due to fatigue

Inter-Rater Agreement of a Functional Dual-Task Test Developed for the Assessment of Sports Related Concussions

Please enjoy Volume 5, Issue 1 of the JSMAHS. In this issue you will find Professional and under graduate research abstracts, case reports, and critically appraised topics. This research was funded by an OATA Research Grant Thank you for viewing this 5th Annual OATA Special Edition

Constitutive modelling of Sandvik 1RK91

A physically based constitutive equation is being developed for the maraging\ud stainless steel Sandvik 1RK91. The steel is used to make precision parts. These parts are formed through multistage forming operations and heat treatments from cold rolled and annealed sheets. The specific alloy is designed to be thermodynamically unstable, so that deformation even at room temperatures can bring about a change in the phase of face centred cubic austenite to either hexagonal closed packed martensite and/or, body centred cubic martensite. This solid state phase change is a function of the strain path, strain, strain rate and temperature. Thus, the fraction of the new phase formed depends on the state of stress at a given location in the part being formed. Therefore a set of experiments is being conducted in order to quantify the stress-strain behavior of this steel under various stress states, strain, strain rate as well as temperature. A magnetic sensor records the fraction of ferromagnetic martensite formed from paramagnetic austenite. A thermocouple as well as an infra red thermometer is used to log the change in temperature of the steel during a mechanical test. The force-displacement data are converted to stress-strain data after correcting for the changes in strain rate and temperature. These data are then cast into a general form of constitutive equation and the transformation equations are derived from Olson-Cohen type functions

Presence of \u3cem\u3ePorphyromonas gingivalis\u3c/em\u3e in gingival squamous cell carcinoma

Periodontal disease has been recently linked to a variety of systemic conditions such as diabetes, cardiovascular disease, preterm delivery, and oral cancer. The most common bacteria associated with periodontal disease, Porphyromonas gingivalis (P. gingivalis) has not yet been studied in the malignant gingival tissues. The objective of this study was to investigate the presence of P. gingivalis in specimens from squamous cell carcinoma patients. We have performed immunohistochemical staining to investigate the presence of P. gingivalis and Streptococcus gordonii (S. gordonii), a non invasive oral bacteria, in paraffin embedded samples of gingival squamous cell carcinoma (n=10) and normal gingiva (n=5). Staining for P. gingivalis revealed the presence of the bacteria in normal gingival tissues and gingival carcinoma, with higher levels (more than 33%,P\u3c0.05) detected in the carcinoma samples. The staining intensity was also significantly enhanced in the malignant tissue by 2 folds (P\u3c0.023) compared to specimens stained for the non‐invasive S. gordonii. P. gingivalis is abundantly present in malignant oral epithelium suggesting a potential association of the bacteria with gingival squamous cell carcinoma

Curricular Satisfaction Levels of National Athletic Trainers\u27 Association- Accredited Postprofessional Athletic Training Graduates

Context: Academic programs rely on outcomes assessments to determine if changes in the curriculum are necessary. Objective: To examine the overall satisfaction levels of graduates (2005-2006) of National Athletic Trainers\u27 Association-accredited postprofessional athletic training education programs as related to the 2002 Standards and Guidelines for Development and Implementation of NATA-Accredited PostProfessional Graduate Athletic Training Education Programs. Design: Original survey instrument and demographic questionnaire. Setting: Online survey instrument. Patients or Other Participants: Of 211 survey recipients, 123 returned surveys (58.29% response rate). Main Outcome Measure(s): Demographic information and satisfaction levels in 10 standard areas (depth of learning, breadth of learning, critical thinking, instructor availability, theoretic basis, writing skills, scholarly growth, community return, leadership, and overall program satisfaction) were obtained. Satisfaction scores were categorized into 10 percentage brackets (eg, 80%-89%) for each standard area. Results: No differences were noted in relation to any of the standard satisfaction areas for evaluation of time off from school. However, graduates who required more than the allotted amount of time to complete their degree were less satisfied in the areas of depth of learning (P = .027), breadth of learning (P = .001), instructor availability (P = .005), writing (P = .022), and overall program satisfaction (P = .016). Conclusions: Graduates were generally satisfied across all areas of their didactic curriculum. However, satisfaction levels were affected if graduates required more than the allotted amount of time to complete their degrees

{\kappa} state solutions for the fermionic massive spin-1/2 particles interacting with double ring-shaped Kratzer and oscillator potentials

In recent years, an extensive survey on various wave equations of relativistic quantum mechanics with different types of potential interactions has been a line of great interest. In this regime, special attention has been given to the Dirac equation because the spin-1/2 fermions represent the most frequent building blocks of the molecules and atoms. Motivated by the considerable interest in this equation and its relativistic symmetries (spin and pseudospin) in the presence of solvable potential model, we attempt to obtain the relativistic bound states solution of the Dirac equation with double ring-shaped Kratzer and oscillator potentials under the condition of spin and pseudospin symmetries. The solutions are reported for arbitrary quantum number in a compact form. the analytic bound state energy eigenvalues and the associated upper- and lower-spinor components of two Dirac particles have been found. Several typical numerical results of the relativistic eigenenergies have also been presented. We found that the existence or absence of the ring shaped potential potential has strong effects on the eigenstates of the Kratzer and oscillator particles with a wide band spectrum except for the pseudospin-oscillator particles where there exist a narrow band gap.Comment: 27 pages, 1 figur

Inter-Rater Agreement and Validity of a Tackling Performance Assessment Scale in Youth American Football

Background: Long term neurologic injury and concussion have been identified as risks from participation in American football. Altering tackling form has been recommended to reduce the risk of neurologic injury caused by head accelerations when tackling. The purpose of this research is to determine the inter-rater agreement and validity of the Qualitative Youth Tackling System (QYTS), a six-item feedback scale to correct tackling form, when utilized by novice and expert raters. Hypothesis: Experienced raters will have higher levels of agreement with each other and with motion capture when compared to novice raters. Methods: Both novice and experienced raters viewed video of youth athletes (ages 9-13) tackling a dummy in a laboratory setting along. The raters identified successful performance according to a binary rating scale for each component. Analysis of both the raters\u27 agreement with each other and with an objective motion capture measure were completed. Results: Fliess\u27 Kappa measures between all raters were found to be moderate for head placement (k=.48), fair for cervical extension (k=.38), trunk inclination (k=.37), shoulder extension (k=.27) and step length (k=.29), and there was no agreement for pelvic height (k=.-16). When compared to the dichotomized validation measures of each of the five components provided by the motion capture system the average Cohen\u27s Kappa agreement was substantial for pelvic height (k=.63), fair for step length (k=.34), cervical extension (k=.40), trunk inclination (k=.35), and slight for shoulder extension (k=.16). The experienced raters out-performed the novice raters in all categories. Conclusion: The results of this study indicate that skilled raters are better able to identify the movement patterns included in the QYTS when compared to a validation measure as well have higher rates of interrater agreement than novice raters. Level of Evidence: 3

The Effect of Tackling Training on Head Accelerations in Youth American Football

Background: Many organizations have introduced frameworks to reduce the incidence of football related concussions through proper equipment fitting, coach education, and alteration of tackling technique. Purpose: The purpose of this study was to examine the effects of training in a vertical, head up tackling style on the number of head accelerations experienced while tackling in a controlled laboratory situation. The authors hypothesized that training in a head up tackling technique would reduce the severity of head acceleration experienced by participants. Design: Controlled Laboratory Study. Methods: Twenty-four participants (11.5 ± 0.6 years old, 60.5 ± 2.2 in, 110 ± 18.4 lbs.) with previous playing experience completed a one-day training session on tackling technique utilizing a tackling dummy. A subgroup of these participants completed an additional two days of training with a 48 hour retention test. Head accelerations were analyzed at baseline and end of training. Feedback consisted of verbal feedback utilizing the Qualitative Youth Tackling Scale (QYTS) and video tackling playback. Results: A significant reduction in the number of peak linear head accelerations over 10 g and peak rotational head accelerations over 1885 deg/s² were found in dummy tackling after training in both the one day and three day training regimens. A significant change in QYTS tackling form score was found between pretest and post-test (p=0.004). Participants with larger steps had a 2.28, 4.42 and 4.14 increased odds ratio of sustaining head accelerations over 10, 15 and 20 g respectively. Conclusions: Training in a vertical, head up tackling style decreased the number of head accelerations over threshold values sustained while tackling; decreased step length may be the driving factor in the effectiveness of this tackling form. Level of Evidence: Level 3

Load absorption force-time characteristics following the second pull of weightlifting derivatives

The purpose of this study was to compare the load absorption force-time characteristics of weightlifting catching and pulling derivatives. Twelve resistance-trained men performed repetitions of the hang power clean (HPC), jump shrug (JS), and hang high pull (HHP) on a force platform with 30, 45, 65, and 80% of their one repetition maximum (1RM) HPC. Load absorption phase duration, mean force, and work were calculated from the force-time data. The HHP produced a significantly longer load absorption phase duration compared to the HPC (p < 0.001, d = 3.77) and JS (p < 0.001, d = 5.48), while no difference existed between the HPC and JS (p = 0.573, d = 0.51). The JS produced significantly greater load absorption mean forces compared to the HPC (p < 0.001, d = 2.85) and HHP (p < 0.001, d = 3.75), while no difference existed between the HPC and HHP (p = 0.253, d = 0.37). Significantly more load absorption work was performed during the JS compared to the HPC (p < 0.001, d = 5.03) and HHP (p < 0.001, d = 1.69), while HHP load absorption work was also significantly greater compared to the HPC (p < 0.001, d = 4.81). The weightlifting pulling derivatives examined in the current study (JS and HHP) produced greater load absorption demands following the second pull compared to the weightlifting catching derivative (HPC). The JS and HHP may be used as effective training stimuli for load absorption during impact tasks such as jumping