29 research outputs found
Influence of the surface layer characteristics on the regularities of the cutting process
The article considers the influence of the surface layer characteristics on the regularities of the cutting process and the formation of the quality of the surface machined. This effect has been confirmed by the study results of the combined cutting method with advanced plastic deformation (APD). The work estimates the impact of the change in the surface layer properties on the forces and temperature of cutting, stability of the chip formation and quality parameters of the surface machined
PHYTOCHEMICAL, MICROBIOLOGICAL, AND TECHNOLOGICAL STUDIES IN THE FIELD OF OBTAINING A HYDROALCOHOLIC EXTRACT WITH ANTIMICROBIAL ACTIVITY FROM THE LIQUORICE ROOT
Objective: The objective of this work was to carry out studies in the field of development of a hydroalcoholic extract from the liquorice root that has a high level of antimicrobial activity.Methods: For the antibacterial study of extracts, we have used the agar well diffusion method. In our research, we have utilized six test-strain microorganisms: Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Proteus vulgaris ATCC 4636, Pseudomonas aeruginosa ATCC 27853, Candida albicans ATCC 885/653, and Bacillus subtilis ATCC 6633. Authors have applied vector theory for antimicrobial activity comparison of liquorice root extracts.Results: Phytochemical composition and antimicrobial activity of hydroalcoholic extracts from the liquorice root with the use of different concentrations of ethanol have been studied. The optimal range of ethanol concentration of 65±15% v/v has been found. The dependency between the integral index of antimicrobial activity of the extract and concentration of glycyram and licuroside has been found. The minimal concentration of glycyram and licuroside in the extract has been calculated for an exhibition of the target level of extract's antimicrobial activity, which is 1.0 and 0.11% w/v, respectively.Conclusion: It has been found that the concentration of licuroside has greater influence on the integral index of extract's antimicrobial activity in comparison with that one of glycyram. A highly effective technology for obtaining an extract with target phytochemical parameters has been suggested
Behaviours and beliefs related to whistleblowing against doping in sport: a cross-national study
Background: Whistleblowing has been recognized as an important deterrent of doping in elite competitive sport. The present study examined athletes’ knowledge of external whistleblowing channels and on how and where to report doping misconduct, perceived trust in different whistleblowing reporting channels, whistleblowing behaviour and athletes’ reasons for reporting (or not) doping misconduct. Methods: Athletes from Greece (n = 480), the Russian Federation (n = 512) and the United Kingdom (n = 171) completed a structured questionnaire on demographics, knowledge of different whistleblowing channels, perceived trust in internal and external whistleblowing channels, past whistleblowing behaviour and reasons for reporting (or not) doping misconduct. Results: The British athletes reported greater awareness of whistleblowing reporting channels (e.g., WADA’s Speak Up and IOC’s reporting platform) than did athletes from Greece (all p < 0.001) and Russia (p = 0.07, and p = 0.012) respectively. However, British athletes reported the lowest scores on knowledge of how and where to report doping misconduct, as compared to athletes from Greece and Russia. The majority of respondents reported greater trust to their coach or a club manager than to other whistleblowing channels, however, responses regarding other channels varied by country. Among athletes who detected doping misconduct 62% of athletes did not report it, while 38% reported it. Reasons for and against reporting doping misconduct reflected in eight themes that were identified using thematic analysis. Conclusion: Athletes showed low awareness of external whistleblowing channels and they predominantly trusted internal whistleblowing channels. Sportspersonship, confidence in resources and personal benefits were among the reasons that facilitate reporting doping misconduct. The present findings indicate that cultural context may play a role in the ways athletes perceive whistleblowing, and this should be taken into account by future interventions to promote the reporting of doping misconduct
Whistleblowing against Doping Misconduct in Sport: A Reasoned Action Perspective with a Focus on Affective and Normative Processes
Whistleblowing against doping misconduct represents an effective deterrent of doping use in elite competitive sport. The present study assessed the effects of social cognitive variables on competitive athletes’ intentions to report doping misconduct. A second objective was to assess whether the effects of social norms on whistleblowing intentions were mediated by actor prototype evaluations and group identification and orientation. In total, 1,163 competitive athletes from Greece, Russia, and the United Kingdom completed a questionnaire on demographics, past behavior, social cognitive variables, and intentions toward whistleblowing. Regression analyses showed that whistleblowing intentions were associated with different social cognitive variables in each country. Multiple mediation modeling showed that attitudes and subjective norms were associated with whistleblowing intentions indirectly, via the effects of anticipated negative affect and group identification and orientation, respectively. The findings of this study are novel and have important implications about the social, cognitive, and normative processes underlying decision making toward reporting doping misconduct
Physical Activity and Nutrition INfluences in Ageing: Current Findings from the PANINI Project
Background: The ageing of the population is a global challenge and the period of life spent in good health, although increasing, is not keeping pace with lifespan. Consequently, understanding the important factors that contribute to healthy ageing and validating interventions and influencing policy to promote healthy ageing are vital research priorities. Method: The PANINI project is a collaboration of 20 partners across Europe examining the influence of physical activity and nutrition in ageing. Methods utilised encompass the biological to the social, from genetics to the influence of social context. For example, epigenetic, immunological, and psychological assessments, and nutritional and sports science-based interventions have been used among older adults, as well as mathematical modelling and epidemiology. The projects are multi-disciplinary and examine health outcomes in ageing from a range of perspectives. Results: The results discussed here are those emerging thus far in PANINI from 11 distinct programmes of research within PANINI as well as projects cross-cutting the network. New approaches, and the latest results are discussed. Conclusions: The PANINI project has been addressing the impact of physical activity and nutrition on healthy ageing from diverse but interlinked perspectives. It emphasises the importance of using standardized measures and the advantages of combining data to compare biomarkers and interventions across different settings and typologies of older adults. As the projects conclude, the current results and final data will form part of a shared dataset, which will be made open access for other researchers into ageing processes.On behalf of the PANINI Consortiu
Body composition in male lifelong trained strength, sprint and endurance athletes and healthy age-matched controls
IntroductionAging involves many physiological processes that lead to decreases in muscle mass and increases in fat mass. While regular exercise can counteract such negative body composition outcomes, masters athletes maintain high levels of exercise throughout their lives. This provides a unique model to assess the impact of inherent aging. The present study compared lean mass and fat mass in young and masters athletes from different sports to age-matched non-athletic individuals.MethodsParticipants included young (20–39 years, n = 109) and older (70–89 years, n = 147) competitive male athletes, and 147 healthy age-matched controls (young = 53, older = 94 males). Athletes were separated into strength (e.g., weightlifters, powerlifters), sprint (e.g., sprint runners, jumpers) and endurance (e.g., long-distance runners, cross-country skiers) athletic disciplines. Body composition was assessed by dual-energy x-ray absorptiometry (DXA). Upper and lower limb lean mass was combined for appendicular lean mass as well as appendicular lean mass index (ALMI; kg/m2). Individuals’ scores were assessed against established cut-offs for low muscle mass, obesity, and sarcopenic obesity to determine prevalence in each group.ResultsALMI was greater in young strength (0.81–2.36 kg/m2, ∼15% and 1.24–2.74 kg/m2, ∼19%) and sprint (95% CI = 0.51–1.61 kg/m2, ∼11% and 0.96–1.97 kg/m2, ∼15%) athletes than in endurance and controls, respectively (all P < 0.001). In masters athletes, only strength athletes had greater ALMI than endurance athletes, but both older strength and sprint athletes had greater ALMI than older controls (0.42–1.27 kg/m2, ∼9% and 0.73–1.67 kg/m2, ∼13%, respectively, both P < 0.001). Fat mass was significantly lower in sprint and endurance athletes compared to strength athletes and controls in both age-groups. Sarcopenic obesity was identified in one young (2%) and eighteen (19%) older controls, while only two older endurance athletes (3%) and one older strength athlete (2%) were identified.DiscussionLifelong competitive sport participation leads to lower prevalence of sarcopenic obesity than a recreationally active lifestyle. This is achieved in strength athletes by emphasizing muscle mass, while sprint and endurance athletes demonstrate low fat mass levels. However, all older athlete groups showed higher fat mass than the young groups, suggesting that exercise alone may not be sufficient to manage fat mass
Elite athletes’ values in action : an important yet complicated aspect in anti-doping education
Values-based education seeks to cultivate personal responsibility, empathy, and integrity to encourage critical reflection on the (anticipated or actual) consequences of one’s choices and behaviours. To comply with the World Anti-Doping Agency's International Standard for Education, anti-doping education programmes must incorporate values-based components. To facilitate this development, we explored how elite athletes interpret and apply their values in various situations throughout their athletic careers. Adopting a qualitative description design, 13 focus groups were conducted with 60 elite athletes from 13 countries participating in 27 sports at national or international levels. Audio recordings were transcribed/translated and analysed using reflexive thematic analysis. Athletes noted that their values guide their actions but struggled to articulate how these values influence their behaviour. Three overarching themes were created to capture: (1) value consciousness and clarity, (2) intrapersonal value continuity, and (3) value conflict and management. Dynamic relationships between athletes’ values, priorities, and decision-making processes were evident. Specifically, the results illustrate shifts in value priorities as athletes matured and progressed in their careers, and across situations to meet situational demands whilst making behaviour personally permissible. To live up to the fundamental principles of values-based education, anti-doping programmes must incorporate activities that facilitate conceptually sound discussions and provide athletes with time and support to unpack the behavioural meaning of their values. Developing athletes’ decision-making abilities through conscious sense-making activities to anticipate the pain of a value transgression and the value of value fulfilment is key to this process
The role of physical activity in the relationship between menopausal status, physical performance and mental well-being
Middle adulthood is often characterized by an onset of a decline in physiological functioning and fluctuations in mental well-being. However, it also represents a time of high functioning in many areas of life. Among women, menopausal status may explain these confusing views. This study investigates physical performance and mental well-being among middle-aged women in relation to their menopausal status. It also explores the role of physical activity in the relationship between menopausal status, physical performance, and mental well-being.
The study utilized cross-sectional (n=1098) and longitudinal data (n=232) from the Estrogen Regulation of Muscle Apoptosis study, which involved Finnish (Jyväskylä area) women aged 47 to 55. Menopausal status (pre-, peri-, or postmenopause) was established by hormonal analysis and bleeding diaries. Perimenopausal women were followed-up until postmenopausal (mean follow-up time 15.6 months). Physical performance was assessed by muscle strength, muscle power, and walking. Positive (life satisfaction and positive affectivity) and negative (depressive symptoms and negative affectivity) dimensions of mental well-being and physical activity were assessed with questionnaires.
Handgrip strength and muscle power were lower in postmenopausal women compared to premenopausal women. The longitudinal data indicated a decline in knee extension strength and muscle power. Postmenopausal women reported greater levels of depressive symptoms than premenopausal women. Higher levels of physical activity were associated with greater knee extension strength and walking distance among peri- and postmenopausal groups and greater muscle power irrespective of menopausal status. After their menopausal transition, women with higher levels of physical activity showed a greater increase in handgrip strength but a greater decline in knee extension strength and power than less physically active women. Higher levels of physical activity were associated with lower level of depressive symptoms and greater level of positive mental well-being irrespective of the menopausal status. Of the investigated physical performance measures, only six-minute walking distance had an independent positive association with positive mental well-being.
High physical activity seems to enable a greater capacity to counteract the observed negative influence of the postmenopausal status on muscle strength and power and mental well-being. In addition, aerobic capacity related to physical performance has unique importance for positive mental well-being.
Keywords: menopause, physical activity, physical performance, mental well-beingKeski-ikää luonnehditaan vaiheeksi, jolloin fyysinen toimintakyky heikkenee ja mielen hyvinvointi heilahtelee. Toisaalta se edustaa vaihetta, jolloin toimintakyky on monilla elämänalueilla parhaimmillaan. Naisten osalta näitä ristiriitaisia havaintoja saattaa selittää vaihdevuosien vaihe. Tässä tutkimuksessa selvitettiin keski-ikäisten naisten fyysistä suorituskykyä ja mielen hyvinvointia suhteessa vaihdevuosien vaiheeseen. Tutkimuksessa selvitettiin myös fyysisen aktiivisuuden roolia vaihdevuosien vaiheen, fyysisen suorituskyvyn ja mielen hyvinvoinnin välisissä suhteissa.
Tutkimuksessa käytettiin Estrogen Regulation of Muscle Apoptosis (ERMA) -tutkimuksen poikkileikkaus- (n=1098) ja pitkittäisaineistoja (n=232). Tutkimuk-seen osallistui 47–55-vuotiaita jyväskyläläisiä naisia. Vaihdevuosien vaihe (pre-, peri- ja postmenopaussi) määriteltiin hormonien ja kuukautispäiväkirjojen avulla. Perimenopausaalisia naisia seurattiin keskimäärin 15.6 kuukautta, postmenopaussiin asti. Fyysistä suorituskykyä selvitettiin lihasvoimaa, alaraajojen voimantuottotehoa ja kävelynopeutta mittaavilla testeillä. Mielen hyvinvoinnin myönteisiä (tyytyväisyys elämään ja positiivinen affektivisuus) ja kielteisiä (masentuneisuuden tuntemukset ja negatiivinen affektiivisuus) ulottuvuuksia sekä fyysistä aktiivisuutta arvioitiin kyselylomakkeilla.
Postmenopausaalisten naisten käden puristusvoima ja voimantuottoteho olivat heikommat kuin premenopausaalisten naisten. Postmenopausaalisilla naisilla oli enemmän masennusoireita kuin premenopausaalisilla naisilla. Korkea fyysinen aktiivisuus oli yhteydessä suurempaan polven ojennusvoimaan ja kuuden minuutin aikaiseen kävelymatkaan (kestävyyskunto) peri- ja postmenopausaalisilla naisilla sekä suurempaan lihasvoimaan vaihdevuosien vaiheesta riippumatta. Siirryttäessä perimenopaussista postmenopaussiin niiden naisten, joiden fyysinen aktiivisuus oli korkeampi, käden puristusvoima lisääntyi, mutta polven ojennusvoima ja voimantuottoteho heikkenivät enemmän kuin naisilla, joiden fyysinen aktiivisuus oli alhaisempi. Riippumatta vaihdevuosien vaiheesta korkea fyysinen aktiivisuus liittyi vähäisempiin masentuneisuuden tuntemuksiin ja runsaampaan myönteiseen hyvinvointiin. Kävelymatka oli yhteydessä myönteiseen mielen hyvinvointiin.
Korkea fyysinen aktiivisuus näyttäisi kumoavan postmenopaussivaiheen negatiivisia yhteyksiä lihasvoimaan ja -voimantuottotehoon sekä mielen hyvinvointiin. Lisäksi kestävyyskunnolla on ainutlaatuinen merkitys myönteiselle mielen hyvinvoinnille.
Avainsanat: vaihdevuodet, fyysinen aktiivisuus, fyysinen suorituskyky, mielen hyvinvoint
On-line diagnostics of the physical and mechanical properties of the surface at the production stage
The article deals with the issues of increasing the efficiency of the formation of the performance of the surface layer of machine parts. The results of computer modeling of thermophysical processes in the cutting zone are presented. The possibility of controlling the process of formation of the surface layer structure on the basis of the measurement of the thermal EMF, which make up the cutting forces, as well as the vibro-acoustic signal is considered
Influence of the surface layer characteristics on the regularities of the cutting process
The article considers the influence of the surface layer characteristics on the regularities of the cutting process and the formation of the quality of the surface machined. This effect has been confirmed by the study results of the combined cutting method with advanced plastic deformation (APD). The work estimates the impact of the change in the surface layer properties on the forces and temperature of cutting, stability of the chip formation and quality parameters of the surface machined