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Antimicrobial activity of Manuka honey against antibiotic resistant strains of the cell wall free bacteria Ureaplasma parvum and Ureaplasma urealyticum
Get PDFThe susceptibility of the cell-wall free bacterial pathogens Ureaplasma spp. to Manuka honey was examined. The minimum inhibitory concentration (MIC) of Manuka honey for four Ureaplasma urealyticum and four Ureaplasma parvum isolates was determined. Sensitivity to honey was also compared to clinical isolates with resistance to tetracycline, macrolide and fluoroquinolone antibiotics. Finally step-wise resistance training was utilised in an attempt to induce increased tolerance to honey. The MIC was dependent on the initial bacterial load with 7.5% and 18.0% w/v honey required to inhibit U. urealyticum at 1 and 106 colour changing units (CCU), respectively, and 4.8% and 15.3% w/v required to inhibit U. parvum at 1 and 106 CCU, respectively. MIC values were consistently lower for U. parvum compared with U. urealyticum. Antimicrobial activity was seen against tetracycline resistant, erythromycin resistant and ciprofloxacin resistant isolates at 105 CCU. No resistance to honey was observed with fifty consecutive challenges at increasing concentrations of honey. This is the first report of the antimicrobial activity of Manuka honey against a cell-wall free bacterial pathogen. The antimicrobial activity was retained against antibiotic resistant strains and it was not possible to generate resistant mutants
Do disinhibited eaters pay increased attention to food cues?
Get PDFThe Three Factors Eating Questionnaire's measure of disinhibited eating is a robust predictor of long-term weight gain. This experiment explored if disinhibited eaters display attentional bias to food cues. Participants (N = 45) completed a visual dot probe task which measured responses to food (energy dense and low energy foods) and neutral cues. Picture pairs were displayed either for a 100 ms or 2000 ms duration. All participants displayed attentional bias for energy dense food items. Indices of attentional bias were largest in disinhibited eaters. Attentional bias in disinhibited eaters appeared to be underpinned by facilitated attention
Functional phases and angular momentum characteristics of Tkatchev and Kovacs
Get PDFUnderstanding the technical requirements and underlying biomechanics of complex release and re-grasp skills on high bar allows coaches and scientists to develop safe and effective training programmes. The aim of this study was to examine the differences in the functional phases between the Tkatchev and Kovacs skills and to explain how the angular momentum demands are addressed. Images of 18 gymnasts performing 10 Tkatchevs and 8 Kovacs at the Olympic Games were recorded (50 Hz), digitised and reconstructed (3D Direct Linear Transformation). Orientation of the functional phase action, defined by the rapid flexion to extension of the shoulders and extension to flexion of the hips as the performer passed through the lower vertical, along with shoulder and hip angular kinematics, angular momentum and key release parameters (body angle, mass centre velocity and angular momentum about the mass centre and bar) were compared between skills. Expected differences in the release parameters of angle, angular momentum and velocity were observed and the specific mechanical requirement of each skill were highlighted. Whilst there were no differences in joint kinematics, hip and shoulder functional phase were significantly earlier in the circle for the Tkatchev. These findings highlight the importance of the orientation of the functional phase in the preceding giant swing and provide coaches with further understanding of the critical timing in this key phase
A longitudinal examination of stressors, appraisals, and coping in youth swimming
Get PDFPurpose
Involvement in sport has the potential to cause athletes, coaches, and parents to experience stress. However, the extent to which experiences of stress are shared within the athletic triad is unknown. The purpose of this study was to examine the individual and shared stress experiences among youth swimmers, their mothers, and coach within the context of training, tapering, and competition.
Design
Multi-case study design.
Method
Four female swimmers, their mother, and one coach completed daily diaries for six weeks and up to three semi-structured interviews. Data were analyzed through within- and cross-case thematic analysis.
Results
The study showed evidence of shared stress experiences between all three members of the athletic triad. Participants predominately encountered organizational stressors, which they appraised in relation to movements between squad, interpersonal relationships, and overall progress towards performance goals/outcomes. Numerous coping strategies were employed by participants, with varying degrees of effectiveness, such as seeking social support, distancing, and lift sharing. The coping strategies used by coaches, swimmers, and parents were often interrelated with participants frequently seeking emotional support from one another. The majority of stressors and appraisals cited by parents and swimmers were shared, with both heavily relying on social support to help each other cope with the stressors encountered.
Conclusion
Athletes, parents, and coaches have the capacity to influence one another's stress experiences and as such their experiences should be considered simultaneously to maximize the impact of interventions
Investigating how the hand interacts with different mobile phones
Get PDFIn this paper we investigate the physical interaction between the hand and three types of mobile device interaction: touchscreen, physical keyboard and stylus. Through a controlled study using video observational analysis, we observed firstly, how the participants gripped the three devices and how these grips were device dependent. Secondly we looked closely at these grips to uncover how participants performed what we call micro-movements to facilitate a greater range of interaction, e.g. reaching across the keyboard. The results extend current knowledge by comparing three handheld device input methods and observing the movements, which the hand makes in five grips. The paper concludes by describing the development of a conceptual design, proposed as a provocation for the opening of dialogue on how we conceive hand usage and how it might be optimized when designed for mobile devices
Are career termination concerns only for athletes? : A case study of the career termination of an elite female coach
Get PDFThis paper presents a case study of an elite female coach and her career termination from a 20+ year career following a critical life incident. A novel autobiographical approach was adopted whereby the participant undertook expressive writing to describe her experiences before, during, and following coaching an athlete at the 2012 Summer Olympic Games. Thematic analysis indicated seven phases related to the participant’s experiences of the critical incident: Build up to the event, the event, the aftermath, recovery and reflection on the event, sampling of new avenues, enlightenment, and career rebirth. The findings reinforce the high demands placed upon elite coaches, the subsequent threats to physical and mental well-being, and the importance of having robust psychological skills and suitable social support to cope with these demands. Implications for preparing and supporting coaches for successful career transition are discusse
A review of selected bee products as potential anti-bacterial, anti-fungal, and anti-viral agents
Get PDFAntimicrobial resistance (AMR) is one of the greatest medical challenges the world faces. It was estimated recently that by 2050, AMR will account for 10 million extra deaths annually with additional economic costs in the region of $100 trillion. In order to combat this, novel antimicrobial agents with a broad spectrum of activity are required. Bee products, including; honey, propolis, defensins, royal jelly, bee pollen and venom have been used to treat infectious diseases for several centuries, although they were largely disregarded by Western medicine during the antibiotic era. There has since been a resurgence in interest in their antimicrobial properties, especially due to their reported activity against multi-drug resistant pathogens displaying high levels of AMR. In this paper we review the current scientific literature of honey, propolis, honey bee, defensins, royal jelly, bee pollen and bee venom. We highlight the antimicrobial activity each of these products has displayed and potential future research directions
The Effects of Caffeine Supplementation on Physiological Responses to Submaximal Exercise in Endurance-Trained Men
Get PDFObjectives
The aim of this study was to evaluate the effects of caffeine on physiological responses to submaximal exercise, with a focus on blood lactate concentration ([BLa]).
Methods
Using a randomised, single-blind, crossover design; 16 endurance-trained, male cyclists (age: 38 ± 8 years; height: 1.80 ± 0.05 m; body mass: 76.6 ± 7.8 kg; : 4.3 ± 0.6 L∙min-1) completed four trials on an electromagnetically-braked cycle ergometer. Each trial consisted of a six-stage incremental test (3 minute stages) followed by 30 minutes of passive recovery. One hour before trials 2–4, participants ingested a capsule containing 5 mg∙kg-1 of either caffeine or placebo (maltodextrin). Trials 2 and 3 were designed to evaluate the effects of caffeine on various physiological responses during exercise and recovery. In contrast, Trial 4 was designed to evaluate the effects of caffeine on [BLa] during passive recovery from an end-exercise concentration of 4 mmol∙L-1.
Results
Relative to placebo, caffeine increased [BLa] during exercise, independent of exercise intensity (mean difference: 0.33 ± 0.41 mmol∙L-1; 95% likely range: 0.11 to 0.55 mmol∙L-1), but did not affect the time-course of [BLa] during recovery (p = 0.604). Caffeine reduced ratings of perceived exertion (mean difference: 0.5 ± 0.7; 95% likely range: 0.1 to 0.9) and heart rate (mean difference: 3.6 ± 4.2 b∙min-1; 95% likely range: 1.3 to 5.8 b∙min-1) during exercise, with the effect on the latter dissipating as exercise intensity increased. Supplement × exercise intensity interactions were observed for respiratory exchange ratio (p = 0.004) and minute ventilation (p = 0.034).
Conclusions
The results of the present study illustrate the clear, though often subtle, effects of caffeine on physiological responses to submaximal exercise. Researchers should be aware of these responses, particularly when evaluating the physiological effects of various experimental interventions
A cognitive prosthesis for complex decision-making
Get PDFWhile simple heuristics can be ecologically rational and effective in naturalistic decision making contexts, complex situations require analytical decision making strategies, hypothesis-testing and learning. Sub-optimal decision strategies – using simplified as opposed to analytic decision rules – have been reported in domains such as healthcare, military operational planning, and government policy making. We investigate the potential of a computational toolkit called “IMAGE” to improve decision-making by developing structural knowledge and increasing understanding of complex situations. IMAGE is tested within the context of a complex military convoy management task through (a) interactive simulations, and (b) visualization and knowledge representation capabilities. We assess the usefulness of two versions of IMAGE (desktop and immersive) compared to a baseline. Results suggest that the prosthesis helped analysts in making better decisions, but failed to increase their structural knowledge about the situation once the cognitive prosthesis is removed
The effect of an acute bout of resistance exercise on carotid artery strain and strain rate
Get PDFArterial wall mechanics likely play an integral role in arterial responses to acute physiological stress. Therefore, this study aimed to determine the impact of low and moderate intensity double-leg press exercise on common carotid artery (CCA) wall mechanics using 2D vascular strain imaging. Short-axis CCA ultrasound images were collected in 15 healthy men (age: 21 ± 3 years; stature: 176.5 ± 6.2 cm; body mass; 80.6 ± 15.3 kg) before, during, and immediately after short-duration isometric double-leg press exercise at 30% and 60% of participants’ one-repetition maximum (1RM: 317 ± 72 kg). Images were analyzed for peak circumferential strain (PCS), peak systolic and diastolic strain rate (S-SR and D-SR) and arterial diameter. Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP) were simultaneously assessed and arterial stiffness indices were calculated post hoc. A two-way repeated measures ANOVA revealed that during isometric contraction, PCS and S-SR decreased significantly (P < 0.01) before increasing significantly above resting levels post-exercise (P < 0.05 and P < 0.01 respectively). Conversely, D-SR was unaltered throughout the protocol (P = 0.25). No significant differences were observed between the 30% and 60% 1RM trials. Multiple regression analysis highlighted that HR, BP and arterial diameter did not fully explain the total variance in PCS, S-SR and D-SR. Acute double-leg press exercise is therefore associated with similar transient changes in CCA wall mechanics at low and moderate intensities. CCA wall mechanics likely provide additional insight into localized intrinsic vascular wall properties beyond current measures of arterial stiffness