scholarly journals The biceps brachii role in the stabilization of the cross punch

2020 ◽  
pp. 13
Author(s):  
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...  
Keyword(s):  
Biceps Brachii ◽  
Upper Limbs ◽  
Activation Pattern ◽  
Skill Levels ◽  
Activation Patterns ◽  
Elastic Impact ◽  
Emg Signal ◽  
The Impact ◽  
Muscular Activation ◽  
Better Than

Purpose: starting from an injury background, we assumed that the biceps brachii’s activations could have an important role in upper limbs injury. In this work we analyzed whether different activations of the biceps brachii impact on the power transfer of the punch and how boxers of different skill levels activate the biceps brachii when deliver a punch according to their skill level and efficacy. Methods: we enrolled, basing on official rankings, 23 skilled (n=6) and unskilled boxers. Subjects were instructed to perform three cross punches directed to a fixed elastic target triggered by the coach whistling, and were monitored through a surface electromyography sensor (EMG) on the biceps brachii to estimate the muscular activation during the performance, and through an accelerometer placed inside the elastic impact target to estimate the impact energy. We analyzed the oscillatory content of the EMG signal in order to assess the muscular activation between skilled and unskilled boxers, and between weak and strong punches. Results: both skilled and unskilled boxers threw strong, medium and weak strikes. Skilled boxers performed better than unskilled boxers (47% vs 25% in the “strong punch” category).The EMG analysis revealed a significant increase of lower and higher frequencies (2-4 Hz and 15-17 Hz) and a decrease on the medium frequencies (7-9 Hz) in the skilled boxers compared to the unskilled boxers in strong punches. Weak punches had a similar activation patterns in the two groups. Conclusions: our results support the hypothesis that skilled boxers adapt their activation pattern of the biceps to better stabilize the punch delivery (and thus increasing the transfer of force).

EMG Activation Pattern during Voluntary Bending and Donning Safety Shoes

2014 ◽  
pp. 234-256
Author(s):  
P. K. Nag ◽  
Varsha Chorsiya ◽  
Anjali Nag
Keyword(s):  
Work Environment ◽  
Motor System ◽  
Health And Safety ◽  
Daily Activities ◽  
Activation Pattern ◽  
Activation Patterns ◽  
Limits Of Stability ◽  
Sensory Motor ◽  
Occupational Task ◽  
Muscular Activation

Posture control is a well-coordinated interplay of sensory-motor system and forms the basis of voluntary movements. The daily activities and occupational task involves voluntary bending in different directions, which if falls beyond the limit of stability can cause slipping, tripping and falling. Further, these accidents are very common in industries where workers have to wear safety shoes to protect their feet from hazards of the work environment. The study elucidates the muscular activation patterns in light of electromyographic (EMG) findings for voluntary bending within limits of stability and with donning of safety shoes. The aim of this chapter is to potentially contribute to occupational health and safety at workplaces. The present findings have implications regarding the viability of muscle adaptability as a putative postural control in preventing postural instability and avoiding injuries.

scholarly journals Advertising Media Impact in Consumer Buying Behavior

2019 ◽  
Vol 8 ◽  
pp. 54-56
Author(s):  
Ashmita Dahal Chhetri
Keyword(s):  
Consumer Behavior ◽  
Young Male ◽  
Electronic Media ◽  
Buying Behavior ◽  
Media Impact ◽  
High Degree ◽  
The Impact ◽  
Buying Behaviors ◽  
The Relationship ◽  
Better Than

Advertisements have been used for many years to influence the buying behaviors of the consumers. Advertisements are helpful in creating the awareness and perception among the customers of a product. This particular research was conducted on the 100 young male and female who use different brands of product to check the influence of advertisement on their buying behavior while creating the awareness and building the perceptions. Correlation, regression and other statistical tools were used to identify the relationship between these variables. The results revealed that the relationship between media and consumer behavior is positive. The adve1tising impact on sales and there is positive and high degree relationship between advertising and consumer behavior. The impact on advertising of a product of electronic media is better than non-electronic media.

scholarly journals A cross-species neural integration of gravity for motor optimization

2021 ◽  
Vol 7 (15) ◽  
pp. eabf7800
Author(s):  
Jeremie Gaveau ◽  
Sidney Grospretre ◽  
Bastien Berret ◽  
Dora E. Angelaki ◽  
Charalambos Papaxanthis
Keyword(s):  
Optimization Strategy ◽  
Motor Patterns ◽  
Activation Patterns ◽  
Single Degree Of Freedom ◽  
Single Degree ◽  
Neural Integration ◽  
Gravity Effects ◽  
Neural Signature ◽  
Experimental Findings ◽  
Muscular Activation

Recent kinematic results, combined with model simulations, have provided support for the hypothesis that the human brain shapes motor patterns that use gravity effects to minimize muscle effort. Because many different muscular activation patterns can give rise to the same trajectory, here, we specifically investigate gravity-related movement properties by analyzing muscular activation patterns during single-degree-of-freedom arm movements in various directions. Using a well-known decomposition method of tonic and phasic electromyographic activities, we demonstrate that phasic electromyograms (EMGs) present systematic negative phases. This negativity reveals the optimal motor plan’s neural signature, where the motor system harvests the mechanical effects of gravity to accelerate downward and decelerate upward movements, thereby saving muscle effort. We compare experimental findings in humans to monkeys, generalizing the Effort-optimization strategy across species.

Differences in muscular activation and fatigue for intermittent and constant load

2005 ◽  
Vol 5 (1) ◽  
pp. 43-56
Author(s):  
Danuta Roman-Liu ◽  
Krzysztof Kȩdzior
Keyword(s):  
External Force ◽  
Upper Limb ◽  
Muscle Activation ◽  
Regression Line ◽  
Constant Load ◽  
Median Frequency ◽  
Experimental Conditions ◽  
Emg Signal ◽  
Limb Posture ◽  
Muscular Activation

The aim of this study was to compare the influence of constant or intermittent load on muscle activation and fatigue. The analysis and assessment of muscular activation and fatigue was based on surface EMG measurements from eight muscles (seven muscles of the right upper limb and trapezius muscle). Two EMG signal parameters were analyzed for each of the experimental conditions distinguished by the value of the external force and the character of the load – constant or intermittent. The amplitude related to its maximum (AMP) and the slope of the regression line between time and median frequency (SMF) were the EMG parameters that were analyzed. The results showed that constant load caused higher muscular fatigue than intermittent load despite the lower value of the external force and lower muscle activation. Results suggest that additional external force might influence muscle activation and fatigue more than upper limb posture. The results of the study support the thesis that all biomechanical factors which influence upper limb load and fatigue (upper limb posture, external force and time sequences) should be considered when work stands and work processes are designed. They also indicate that constant load should be especially avoided.

scholarly journals Locking down the Impact of New Zealand’s COVID-19 Alert Level Changes on Pets

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 758
Author(s):  
Fiona Esam ◽  
Rachel Forrest ◽  
Natalie Waran
Keyword(s):  
New Zealand ◽  
Separation Anxiety ◽  
National Surveys ◽  
Normal Life ◽  
Pet Owners ◽  
Level 1 ◽  
The Impact ◽  
Better Than

The influence of the COVID-19 pandemic on human-pet interactions within New Zealand, particularly during lockdown, was investigated via two national surveys. In Survey 1, pet owners (n = 686) responded during the final week of the five-week Alert Level 4 lockdown (highest level of restrictions—April 2020), and survey 2 involved 498 respondents during July 2020 whilst at Alert Level 1 (lowest level of restrictions). During the lockdown, 54.7% of owners felt that their pets’ wellbeing was better than usual, while only 7.4% felt that it was worse. Most respondents (84.0%) could list at least one benefit of lockdown for their pets, and they noted pets were engaged with more play (61.7%) and exercise (49.7%) than pre-lockdown. Many respondents (40.3%) expressed that they were concerned about their pet’s wellbeing after lockdown, with pets missing company/attention and separation anxiety being major themes. In Survey 2, 27.9% of respondents reported that they continued to engage in increased rates of play with their pets after lockdown, however, the higher levels of pet exercise were not maintained. Just over one-third (35.9%) of owners took steps to prepare their pets to transition out of lockdown. The results indicate that pets may have enjoyed improved welfare during lockdown due to the possibility of increased human-pet interaction. The steps taken by owners to prepare animals for a return to normal life may enhance pet wellbeing long-term if maintained.

The Impact of Between-Wave Engagement Strategies on Response to a Longitudinal Survey

2015 ◽  
Vol 57 (4) ◽  
pp. 533-554 ◽  
Author(s):  
Andrew Cleary ◽  
Nigel Balmer
Keyword(s):  
Longitudinal Survey ◽  
Longitudinal Surveys ◽  
Face To Face ◽  
Participant Engagement ◽  
Engagement Strategies ◽  
Design Attributes ◽  
New Research ◽  
The Impact ◽  
Better Than

Maintaining participant engagement in longitudinal surveys has been a key focus of survey research, and has implications for the quality of response and cost of administration. This paper presents new research measuring the impact of the design of between-wave keeping-in-touch mailings on response to the mailing and subsequent wave of a longitudinal survey. Three design attributes of the mailings were randomly implemented: the form of response request (whether respondents were asked to respond only if their address had changed, or in all cases to confirm or update their address); the newsletter included with the mailing (contrasting a newsletter with content tailored to respondent characteristics with a general newsletter and no newsletter); and the outgoing postage used (stamped or franked). The experiments were fielded on a new longitudinal study, the English and Welsh Civil and Social Justice Panel Survey (CSJPS), and took place between waves one and two. Fieldwork for both waves was conducted by Ipsos MORI face-to-face interviewers. Our main finding was that the tailored newsletter was associated with a significant increase in the wave-two response rate. However, in relation to response to the request, the tailored newsletter, or sending no newsletter at all, were equally effective at inducing response, and significantly better than the general newsletter. We also found that, in relation to the form of request, the ‘change of address’ request was as effective as the more costly ‘confirmation’ request. Findings are discussed with reference to the design of keeping-in-touch mailings for longitudinal surveys.

Effect of female executives on Chinese cultural media enterprise efficiency

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ying Li ◽  
Yung-Ho Chiu ◽  
Tai-Yu Lin ◽  
Hongyi Cen
Keyword(s):  
Boards Of Directors ◽  
Company Performance ◽  
Tobit Regression ◽  
Female Executives ◽  
Two Stage ◽  
Content Type ◽  
Female Directors ◽  
The Impact ◽  
Cultural Media ◽  
Better Than

Purpose As more women are now being appointed to senior and top management positions and invited to sit on boards of directors, they are now directly participating in strategic company decision-making. As female directors have been found to provide new ideas, increase company competitiveness, efficiency and performance and bring a greater number of external resources to a company than male directors, this paper aims to put female directors as a variable into the data envelopment analysis (DEA) and statistical models to explore the effect of female directors on operating performances. The DEA first quantified and measured the company efficiencies, after which the statistical model analyzed the correlations between the variables to specifically identify the impact of female decision makers on the operating efficiencies in state-owned and private enterprises. Design/methodology/approach A novel two-stage, meta-hybrid dynamic DEA was developed to explore Chinese cultural media company efficiencies under optimal input and output resource allocations, after which Tobit Regression was applied to determine the effect of female executives on these efficiencies. Findings From 2012 to 2016, the overall efficiencies in Chinese state-owned cultural media enterprises were better than in the private cultural media enterprises. The overall technology gaps (TGs) in the state-owned cultural media enterprises were better than in the private cultural media enterprises. Originality/value Previous research has tended to focus on the causal relationships between female senior executives and business performances; however, there have been few studies on the relationships between female executives and company performance from an efficiency perspective (optimal resource allocation). This paper, therefore, is the first to develop a novel two-stage, meta-hybrid dynamic DEA to examine Chinese cultural media enterprise efficiencies, and the first to apply Tobit Regression to assess the effect of female executives on those efficiencies.

Simulation Analysis of Penetration Performance of Tungsten Alloy and Tungsten Carbide Rod Penetrator

2012 ◽  
Vol 182-183 ◽  
pp. 283-287
Author(s):  
Qun Biao Wu ◽  
Pei Hui Shen ◽  
Rong Zhong Liu
Keyword(s):  
Tungsten Carbide ◽  
Simulation Analysis ◽  
Tungsten Alloy ◽  
Distinct Advantage ◽  
Penetration Mechanics ◽  
Armor Steel ◽  
The One ◽  
The Impact ◽  
Better Than ◽  
And Tungsten

In penetration mechanics, the material parameters of the rod penetrator are very important factors which influence the effect of penetration. The effect of each parameter changes with the impact velocity. Simulation analysis of two models filled with tungsten alloy and tungsten carbide separately penetrating semi-infinite armor steel target at medium to high velocities has been made to quantitatively analyze the key roles that the density and hardness play. Simulation results indicate that a dividing line of velocity exists between the penetrations of two materials. Above the line, tungsten alloy rod with greater density has a distinct advantage with increasing velocity. Below the line, the advantage of tungsten carbide rod with greater hardness is significantly more with the decreasing velocity. In the process of penetration, penetration velocity decreases rapidly from a high value to zero. The simulation result provides quantitative analytic basis which can be used to prove that the penetrator composed of two different materials is better than the one composed of homogenous material.

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