2,176 research outputs found

    AN ANALYSIS OF MOVEMENT PATTERNS UTILIZED BY DIFFERENT STYLES IN THE KARATE REVERSE PUNCH IN FRONT STANCE

    Get PDF
    Research Hypotheses The purpose of this study was to obtain baseline kinematic data on the spatial and temporal organization of selected segmental movements of the body during the execution of the karate reverse punch in front stance. The two research hypotheses (H) tested in the study were: H1: The reverse punch in front stance when performed by advanced performers (karateka) will conform to the "kinetic link principle" and "serape effect" movement models. H2: A similar movement pattern will appear irrespective of karate style

    AN ANALYSIS OF WORK AND POWER PRODUCED BY DIFFERENT KARATE STYLES IN THE KARATE REVERSE PUNCH IN FRONT STANCE

    Get PDF
    Introduction The purpose ofthis study was to obtain baseline kinematic data on the work and power produced by different karate styles in the karate reverse punch in front stance. It is the second part of a two part study on the kinematics of the reverse punch in front stance. The first part, which dealt with an analysis of movement patterns is presented elsewhere in these proceedings. (Stull and Barham, 1988) Four black belt performers were selected as subjects for these two studies. One subject was selected to represent each ofthe four karate styles studied, which were Shotokan, Tae Kwon Do, Kung-fu, and Kempo. Each of these styles placed emphasis on the reverse punch in front stance, and each subject was highly skilled in the execution of this technique. The subjects were allowed to use their dominant punching hand and were filmed at 100 frames per second with the camera located perpendicular to the sagittal plane of the movement. It was hypothesized that the work and power involved in the execution of the karate reverse punch in front stance would be approximately the same for all styles

    First-principles investigation of Ag-Cu alloy surfaces in an oxidizing environment

    Get PDF
    In this paper we investigate by means of first-principles density functional theory calculations the (111) surface of the Ag-Cu alloy under varying conditions of pressure of the surrounding oxygen atmosphere and temperature. This alloy has been recently proposed as a catalyst with improved selectivity for ethylene epoxidation with respect to pure silver, the catalyst commonly used in industrial applications. Here we show that the presence of oxygen leads to copper segregation to the surface. Considering the surface free energy as a function of the surface composition, we construct the convex hull to investigate the stability of various surface structures. By including the dependence of the free surface energy on the oxygen chemical potential, we are able compute the phase diagram of the alloy as a function of temperature, pressure and surface composition. We find that, at temperature and pressure typically used in ethylene epoxidation, a number of structures can be present on the surface of the alloy, including clean Ag(111), thin layers of copper oxide and thick oxide-like structures. These results are consistent with, and help explain, recent experimental results.Comment: 10 pages, 6 figure

    The Effect of the Environment on alpha-Al_2O_3 (0001) Surface Structures

    Full text link
    We report that calculating the Gibbs free energy of the alpha-Al_2O_3 (0001) surfaces in equilibrium with a realistic environment containing both oxygen and hydrogen species is essential for obtaining theoretical predictions consistent with experimental observations. Using density-functional theory we find that even under conditions of high oxygen partial pressure, the metal terminated surface is surprisingly stable. An oxygen terminated alpha-Al_2O_3 (0001) surface becomes stable only if hydrogen is present on the surface. In addition, including hydrogen on the surface resolves discrepancies between previous theoretical work and experimental results with respect to the magnitude and direction of surface relaxations.Comment: 4 pages including 2 figures. Submitted to Phys. Rev. Lett. Related publications can be found at http://www.fhi-berlin.mpg.de/th/paper.htm

    Stochastic analysis of surface roughness

    Full text link
    For the characterization of surface height profiles we present a new stochastic approach which is based on the theory of Markov processes. With this analysis we achieve a characterization of the complexity of the surface roughness by means of a Fokker-Planck or Langevin equation, providing the complete stochastic information of multiscale joint probabilities. The method was applied to different road surface profiles which were measured with high resolution. Evidence of Markov properties is shown. Estimations for the parameters of the Fokker-Planck equation are based on pure, parameter free data analysis

    Internet-of-Things Devices in Support of the Development of Echoic Skills Among Children with Autism Spectrum Disorder

    Get PDF
    A significant therapeutic challenge for people with disabilities is the development of verbal and echoic skills. Digital voice assistants (DVAs), such as Amazon’s Alexa, provide networked intelligence to billions of Internet-of-Things devices and have the potential to offer opportunities to people, such as those diagnosed with autism spectrum disorder (ASD), to advance these necessary skills. Voice interfaces can enable children with ASD to practice such skills at home; however, it remains unclear whether DVAs can be as proficient as therapists in recognizing utterances by a developing speaker. We developed an Alexa-based skill called ASPECT to measure how well the DVA identified verbalization by autistic children. The participants, nine children diagnosed with ASD, each participated in 30 sessions focused on increasing vocalizations and echoic responses. Children interacted with ASPECT prompted by instructions from an Echo device. ASPECT was trained to recognize utterances and evaluate them as a therapist would—simultaneously, a therapist scored the child’s responses. The study identified no significant difference between how ASPECT and the therapists scored participants; this conclusion held even when subsetting participants by a pre-treatment echoic skill assessment score. This indicates considerable potential for providing a continuum of therapeutic opportunities and reinforcement outside of clinical settings

    Weight loss and competition weight in Ultimate Fighting Championship (UFC) athletes

    Get PDF
    Previous research has demonstrated that professional mixed martial arts (MMA) athletes employ a variety of weight manipulation strategies to compete at given weight classes. Although there is much literature demonstrating weight manipulation methods, minimal research exists analyzing how much weight MMA athletes lose prior to the official weigh-in. Moreover, there is minimal research examining how much weight professional MMA athletes gain between the official weigh-in and competition. Therefore, the purpose of the current study was to analyze weight loss/regain in professional MMA athletes. Data collected from 616 professional MMA athletes (31.1 ± 4.0 yrs. ; 177.1 ± 4.7 cm) competing for the Ultimate Fighting Championship (UFC) between 2020 and 2022 were used for the study. The athlete’s weight was obtained 72 h, 48 h, and 24 h prior to the official weigh-in, at the official weigh-in, and prior to competition. Random effects analysis was utilized to compare weight at a variety of time points between different weight classes. All statistics were analyzed, and significance was set at p ≤ 0.05. There is a significant (p ≤ 0.05) difference between weight classes and time points in professional MMA. MMA athletes decrease body weight significantly prior to the official weigh-in. MMA athletes increase body weight significantly between official weigh-in and competition. Based on these data, it appears that MMA athletes average a weight loss of nearly 7 % within 72 h prior to the official weigh-in. The data also suggest that athletes gain nearly 10 % of total weight between the official weigh-in and competition

    A Comparison of Phone-Based and On-Site Assessment of Fidelity for Assertive Community Treatment in Indiana

    Get PDF
    Objective: This study investigated the reliability and validity of a phone-administered fidelity assessment instrument based on the Dartmouth Assertive Community Treatment Scale (DACTS). Methods: An experienced rater paired with a research assistant without fidelity assessment experience or a consultant familiar with the treatment site conducted phone-based assessments of 23 teams providing assertive community treatment in Indiana. Using the DACTS, consultants conducted on-site evaluations of the programs. Results: The pairs of phone raters revealed high levels of consistency [intraclass correlation coefficient (ICC)=.92] and consensus (mean absolute difference of .07). Phone and on-site assessment showed strong agreement (ICC=.87) and consensus (mean absolute difference of .07) and agreed within .1 scale point, or 2% of the scoring range, for 83% of sites and within .15 scale point for 91% of sites. Results were unaffected by the expertise level of the rater. Conclusions: Phone-based assessment could help agencies monitor faithful implementation of evidence-based practices. (Psychiatric Services 62:670–674, 2011

    Self-reported evaluation of competencies and attitudes by physicians-in-training before and after a single day legislative advocacy experience

    Get PDF
    BACKGROUND: Advocacy is increasingly being recognized as a core element of medical professionalism and efforts are underway to incorporate advocacy training into graduate and undergraduate medical school curricula. While limited data exist to quantify physician attitudes toward advocacy, even less has been done to assess the knowledge, skills, and attitudes of future physicians. The purpose of this study was to assess students’ experiences and attitudes toward legislative advocacy, cutting out using a convience sample. METHODS: A paper survey based on previously validated surveys was administered to a convenience sample of premedical and medical student participants attending a National Advocacy Day in Washington, DC, in March 2011, both before and after their advocacy experiences. Responses were anonymous and either categorical ( or ordinal, using a 5-point Likert scale. Data were analyzed statistically to evaluate demographics and compare changes in pre- and post-experience attitude and skills. RESULTS: Data from 108 pre-advocacy and 50 post-advocacy surveys were analyzed yielding a response rate of 46.3%. Following a single advocacy experience, subjects felt they were more likely to contact their legislators about healthcare issues (p = 0.03), to meet in person with their legislators (p < 0.01), and to advocate for populations' health needs (p = 0.04). Participants endorsed an increased perception of the role of a physician advocate extending beyond individual patients (p = 0.03). Participants disagreed with the statement that their formal curricula adequately covered legislative healthcare advocacy. Additionally, respondents indicated that they plan to engage in legislative advocacy activities in the future (p < 0.01). CONCLUSIONS: A one-time practical advocacy experience has a positive influence on students’ knowledge, skills and attitudes towards legislative advocacy. Practical experience is an important method of furthering medical education in advocacy and further research is necessary to assess its impact in a broader population

    The iron/heme regulated genes of Haemophilus influenzae: comparative transcriptional profiling as a tool to define the species core modulon

    Get PDF
    <p>Abstract</p> <p>Background</p> <p><it>Haemophilus influenzae </it>requires heme for aerobic growth and possesses multiple mechanisms to obtain this essential nutrient. Although an understanding of the heme acquisition mechanisms of <it>H. influenzae </it>is emerging, significant gaps in our knowledge remain. Unresolved issues include the identities of all genes exhibiting altered transcription in response to iron and heme availability, the fraction of such genes functioning in iron/heme acquisition, and the heterogeneity of this gene set among clinical isolates. Previously we utilized <it>H. influenzae </it>strain Rd KW20 to demonstrate the utility of transcriptional profiling in defining the genes exhibiting altered transcription in response to environmental iron and heme levels. The current study expands upon those observations by determining the iron/heme modulons of two clinical isolates, the type b isolate 10810 and the nontypeable isolate R2866. These data are used to begin to define the core iron/heme modulon of the species.</p> <p>Results</p> <p>Microarray studies were performed to compare gene expression on transition from iron/heme-restricted to iron/heme-replete conditions for each isolate. Of 1820 ORFs on the array corresponding to R2866 genes, 363 were significantly differentially expressed: 233 were maximally transcribed under iron/heme-replete conditions and 130 under iron/heme-restricted conditions. Of the 1883 ORFs representing genes of strain 10810, 353 were significantly differentially transcribed: 150 were preferentially transcribed under iron/heme-replete conditions and 203 under iron/heme-restricted conditions. Comparison of the data sets indicated that 163 genes exhibited similar regulation in both isolates and that 74 of these exhibited similar patterns of regulation in Rd KW20. These comprise the putative core iron/heme modulon.</p> <p>Conclusion</p> <p>This study provides evidence for a conserved core of <it>H. influenzae </it>genes the transcription of which is altered by the availability of iron and/or heme in the growth environment. Elucidation of this modulon provides a means to identify genes with unrecognized roles in iron/heme acquisition or homeostasis, unanticipated responsiveness to environmental levels of the micronutrients or potential roles in virulence. Defining these core genes is also of potential importance in identifying targets for therapeutic and vaccine designs since products of these genes are likely to be preferentially expressed during growth in iron/heme restricted sites of the human body.</p
    • …
    corecore