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Herein, the first study is presented using 4D synchrotron X-ray microtomography to capture all stages of crack development in neutron irradiated and radiolytically oxidised nuclear graphite. Employing a novel loading setup, specimens of Gilsocarbon graphite, both unirradiated and irradiated at 301 °C to 19.7 × 1020 neutrons/cm2 (∼2.6 displacements/atom (dpa)), were loaded to generate a crack. All stages of the fracture process were then captured using synchrotron X-ray imaging. Reconstructed tomographic images and 3D segmented crack volumes have been used to observe and analyse the irradiation-induced evolution of the graphite microstructure as well as corresponding changes in the crack initiation, propagation, and arrest behaviour of graphite after neutron irradiation. Close examination of the applied stress-strain curves highlights the suppression of micro-crack-based damage accumulation in irradiated graphite. Moreover, as well as the crack-bridging and deflection mechanisms characteristic of unirradiated graphite, crack arrest in the irradiated graphite is shown to be significantly influenced by crack tip blunting. This change is associated with the growth of the open pore structure of graphite, specifically the enlargement and increased frequency of macro-pores, resulting from the simultaneous radiolytic oxidation of the graphite microstructure during neutron irradiation.

Background Recent studies have revealed that many discharged patients with COVID-19 experience ongoing symptoms months later. Rehabilitation interventions can help address the consequences of COVID-19, including medical, physical, cognitive, and psychological problems. To our knowledge, no studies have investigated the effects of rehabilitation following discharge from hospital for patients with COVID-19. Objective The specific aims of this project are to investigate the effects of a 12-week exercise program on pulmonary fibrosis in patients recovering from COVID-19. A further aim will be to examine how Chinese herbal medicines as well as the gut microbiome and its metabolites regulate immune function and possibly autoimmune deficiency in the rehabilitation process. Methods In this triple-blinded, randomized, parallel-group, controlled clinical trial, we will recruit adult patients with COVID-19 who have been discharged from hospital in Hong Kong and are experiencing impaired lung function and pulmonary function. A total of 172 eligible patients will be randomized into four equal groups: (1) cardiorespiratory exercise plus Chinese herbal medicines group, (2) cardiorespiratory exercise only group, (3) Chinese herbal medicines only group, and (4) waiting list group (in which participants will receive Chinese herbal medicines after 24 weeks). These treatments will be administered for 12 weeks, with a 12-week follow-up period. Primary outcomes include dyspnea, fatigue, lung function, pulmonary function, blood oxygen levels, immune function, blood coagulation, and related blood biochemistry. Measurements will be recorded prior to initiating the above treatments and repeated at the 13th and 25th weeks of the study. The primary analysis is aimed at comparing the outcomes between groups throughout the study period with an α level of .05 (two-tailed). Results The trial has been approved by the university ethics committee following the Declaration of Helsinki (approval number: REC/19-20/0504) in 2020. The trial has been recruiting patients. The data collection will be completed in 24 months, from January 1, 2021, to December 31, 2022. Conclusions Given that COVID-19 and its sequelae would persist in human populations, important findings from this study would provide valuable insights into the mechanisms and processes of COVID-19 rehabilitation. Trial Registration ClinicalTrials.gov NCT04572360; https://clinicaltrials.gov/ct2/show/NCT04572360 International Registered Report Identifier (IRRID) PRR1-10.2196/25556

BACKGROUND Recent studies have revealed that many discharged patients with COVID-19 experience ongoing symptoms months later. Rehabilitation interventions can help address the consequences of COVID-19, including medical, physical, cognitive, and psychological problems. To our knowledge, no studies have investigated the effects of rehabilitation following discharge from hospital for patients with COVID-19. OBJECTIVE The specific aims of this project are to investigate the effects of a 12-week exercise program on pulmonary fibrosis in patients recovering from COVID-19. A further aim will be to examine how Chinese herbal medicines as well as the gut microbiome and its metabolites regulate immune function and possibly autoimmune deficiency in the rehabilitation process. METHODS In this triple-blinded, randomized, parallel-group, controlled clinical trial, we will recruit adult patients with COVID-19 who have been discharged from hospital in Hong Kong and are experiencing impaired lung function and pulmonary function. A total of 172 eligible patients will be randomized into four equal groups: (1) cardiorespiratory exercise plus Chinese herbal medicines group, (2) cardiorespiratory exercise only group, (3) Chinese herbal medicines only group, and (4) waiting list group (in which participants will receive Chinese herbal medicines after 24 weeks). These treatments will be administered for 12 weeks, with a 12-week follow-up period. Primary outcomes include dyspnea, fatigue, lung function, pulmonary function, blood oxygen levels, immune function, blood coagulation, and related blood biochemistry. Measurements will be recorded prior to initiating the above treatments and repeated at the 13th and 25th weeks of the study. The primary analysis is aimed at comparing the outcomes between groups throughout the study period with an α level of .05 (two-tailed). RESULTS The trial has been approved by the university ethics committee following the Declaration of Helsinki (approval number: REC/19-20/0504) in 2020. The trial has been recruiting patients. The data collection will be completed in 24 months, from January 1, 2021, to December 31, 2022. CONCLUSIONS Given that COVID-19 and its sequelae would persist in human populations, important findings from this study would provide valuable insights into the mechanisms and processes of COVID-19 rehabilitation. CLINICALTRIAL ClinicalTrials.gov NCT04572360; https://clinicaltrials.gov/ct2/show/NCT04572360 INTERNATIONAL REGISTERED REPORT PRR1-10.2196/25556

For the earliest Universe, a constant Planck energy density inflow with expansion at the speed of light is the only model that attains the finite mass of the observable Universe when the Higg's Field interacts. The conservation laws, as in Feynman's Diagrams, demand that the Higg's Field produce equal and opposite charged quarkgluon and antiquark-gluon balls of plasma moving in opposite directions. Regge calculus confirms this duality formation. Einsteins Field/wave equation for gravitational potential only has solutions with two equal and opposite propagating waves. The initial expansion of the Universe is a flow wherein, at the critical Reynold's Number, two equal and opposite vortices will form. That all these wellproven models of physical reality result in equal and opposite entities gives much credibility to the Higg's Field birthing our Universe of matter and its antimatter twin. &nbsp

KEY POINTS In vitro evidence has identified that coagulation is activated by increased oxidative stress, though the link and underlying mechanism in humans have yet to be established. We conducted the first randomised controlled trial in healthy participants to examine if oral antioxidant prophylaxis alters the haemostatic responses to hypoxia and exercise given their synergistic capacity to promote free radical formation. Systemic free radical formation was shown to increase during hypoxia and was further compounded by exercise, responses that were attenuated by antioxidant prophylaxis. In contrast, antioxidant prophylaxis increased thrombin generation at rest in normoxia, and this was normalised only in the face of prevailing oxidation. Collectively, these findings suggest that human free radical formation is an adaptive phenomenon that serves to maintain vascular haemostasis. ABSTRACT In vitro evidence suggests that blood coagulation is activated by increased oxidative stress although the link and underlying mechanism in humans have yet to be established. We conducted the first randomised controlled trial to examine if oral antioxidant prophylaxis alters the haemostatic responses to hypoxia and exercise. Healthy males were randomly assigned double-blind to either an antioxidant (n = 20) or placebo group (n = 16). The antioxidant group ingested two capsules/day that each contained 500 mg of l-ascorbic acid and 450 international units (IU) of dl-α-tocopherol acetate for 8 weeks. The placebo group ingested capsules of identical external appearance, taste and smell (cellulose). Both groups were subsequently exposed to acute hypoxia and maximal physical exercise with venous blood sampled pre-supplementation (normoxia), post-supplementation at rest (normoxia and hypoxia) and following maximal exercise (hypoxia). Systemic free radical formation (electron paramagnetic resonance spectroscopic detection of the ascorbate radical (A•- )) increased during hypoxia (15,152 ± 1193 AU vs. 14,076 ± 810 AU at rest, P

Property measurement of graphite extracted from operational nuclear reactors is vital for forward prediction of the graphite's properties and integrity as part of continued operation and plant life extension assessments. Limited core monitoring material is available, so robust and efficient measurement techniques are required for samples with constrained dimensions. The validation of a technique for measuring electrical resistivity in small graphite samples (largest dimension

The Young's modulus, Poisson's ratio and flexural strength of 218 beams of radiolytically oxidised nuclear graphite have been determined by combining electronic speckle pattern interferometry, ESPI, and inverse finite element modelling techniques. The graphite was extracted from three operational advanced gas cooled reactor stations where it had been subjected to fast neutron irradiation and radiolytic oxidation resulting in mass loss. The 6 × 6 × 19 mm beam samples had densities ranging from 1063 – 1840 kg.m−3, equivalent to weight losses up to 46 %, with cumulative neutron doses of up to 161 × 1020 n.cm−2 equivalent Dido nickel dose, or 21.1 displacements per atom, significantly extending the datasets available in the open literature to higher levels of both dose and oxidation. In situ ESPI measurements were collected during three-point bend tests, creating full field displacement maps of the evolving deformation to which simulations were matched by chi-squared minimisation of the elastic properties. Potential loading abnormalities were accounted for in the fitting process to ensure the simulations were representative, with total uncertainties in the determined Young's modulus and Poisson's ratio values of ± 4.5 % and ± 0.08, respectively. Consistent trends were observed in the behaviour of the material from the different stations, with strong positive dependences on density for both the flexural strength and Young's modulus. The strength and Young's modulus remained well correlated even to high levels of oxidation mass loss. Conversely, the Poisson's ratio was practically invariant with oxidation with mean values of 0.21 ± 0.03, 0.24 ± 0.05 and 0.25 ± 0.05 for the three stations. The combined ESPI-finite element measurement approach is demonstrated as robust for irradiated small specimens, making it suitable for monitoring graphite in future reactors. The collected data support the safety assessments of the current reactors, enabling predictions of the responses to progressively higher mean core mass loss.

Keyway root cracking and radiolytic weight loss in graphite moderated nuclear reactors may limit future successful operation of the civil nuclear fleet. A novel means of initiating fracture using internally generated stresses has been developed, which uses bromine intercalation to induce fracture in small graphite samples. Successful crack initiation and propagation has been achieved in 1:10 scale reactor components. In situ X-ray Computed Tomography during bromination has enabled observations of failure in real time, allowing the role of microstructure during fracture and weight loss to be determined. Crack paths predicted by models have been assessed.

Objectives National dietary guidelines were introduced in 1977 and 1983, by the US and UK governments to reduce coronary heart disease (CHD) mortality by reducing dietary fat intake. Our 2016 systematic review examined the epidemiological evidence available to the dietary committees at the time; we found no support for the recommendations to restrict dietary fat. The present investigation extends our work by re-examining the totality of epidemiological evidence currently available relating to dietary fat guidelines. Methods A systematic review and meta-analysis of prospective cohort studies currently available, which examined the relationship between dietary fat, serum cholesterol and the development of CHD, were undertaken. Results Across 7 studies, involving 89 801 participants (94% male), there were 2024 deaths from CHD during the mean follow-up of 11.9±5.6 years. The death rate from CHD was 2.25%. Eight data sets were suitable for inclusion in meta-analysis; all excluded participants with previous heart disease. Risk ratios (RRs) from meta-analysis were not statistically significant for CHD deaths and total or saturated fat consumption. The RR from meta-analysis for total fat intake and CHD deaths was 1.04 (95% CI 0.98 to 1.10). The RR from meta-analysis for saturated fat intake and CHD deaths was 1.08 (95% CI 0.94 to 1.25). Conclusions Epidemiological evidence to date found no significant difference in CHD mortality and total fat or saturated fat intake and thus does not support the present dietary fat guidelines. The evidence per se lacks generalisability for population-wide guidelines.

Objectives National dietary guidelines were introduced in 1977 and 1983, by the USA and UK governments to reduce coronary heart disease (CHD) mortality by reducing dietary fat intake. Our 2015 systematic review examined randomised controlled trial (RCT) evidence available to the dietary committees at the time; we found no support for the recommendations to restrict dietary fat. What epidemiological evidence was available to the dietary guideline committees in 1983? Methods A systematic review of prospective cohort studies, published prior to 1983, which examined the relationship between dietary fat, serum cholesterol and the development of CHD. Results Across 6 studies, involving 31 445 participants, there were 1521 deaths from all-causes and 360 deaths from CHD during the mean follow-up of 7.5±6.2 years. The death rates were 4.8% and 1.1% from all-causes and CHD respectively. One study included men with previous heart disease. The death rate from CHD for those with, and without previous myocardial infarction was 20.9% and 1.0% respectively. None of the six studies found a significant relationship between CHD deaths and total dietary fat intake. One of the six studies found a correlation between CHD deaths and saturated dietary fat intake across countries; none found a relationship between CHD deaths and saturated dietary fat in the same population. Conclusions 1983 dietary recommendations for 220 million US and 56 million UK citizens lacked supporting evidence from RCT or prospective cohort studies. The extant research had been undertaken exclusively on males, so lacked generalisability for population-wide guidelines.

This study evaluated the effect of game venue and starting status on precompetitive psychophysiological measures in elite rugby union. Saliva samples were taken from players (starting XV, n = 15, and nonstarters, n = 9) on a control day and 90 min before 4 games played consecutively at home and away venues against local rivals and league leaders. Precompetition psychological states were assessed using the Competitive State Anxiety Inventory−2. The squad recorded 2 wins (home) and 2 losses (away) over the study period. Calculated effect sizes (ESs) showed higher pregame cortisol- (C) and testosterone- (T) difference values before all games than on a baseline control day (ES 0.7−1.5). Similar findings were observed for cognitive and somatic anxiety. Small between-venues C differences were observed in starting XV players (ES 0.2−0.25). Conversely, lower home T- (ES 0.95) and higher away C- (ES 0.6) difference values were observed in nonstarters. Lower T-difference values were apparent in nonstarters (vs starting XV) before home games, providing evidence of a between-groups effect (ES 0.92). Findings show an anticipatory rise in psychophysiological variables before competition. Knowledge of starting status appears a moderating factor in the magnitude of player endocrine response between home and away games.

The aim of this study was to assess the appearance of cardiac troponins (cTnI and/or cTnT) after a short bout (30 s) of 'all-out' intense exercise and to determine the stability of any exercise-related cTnI release in response to repeated bouts of high intensity exercise separated by 7 days recovery. Eighteen apparently healthy, physically active, male university students completed two all-out 30 s cycle sprint, separated by 7 days. cTnI, blood lactate and catecholamine concentrations were measured before, immediately after and 24 h after each bout. Cycle performance, heart rate and blood pressure responses to exercise were also recorded. Cycle performance was modestly elevated in the second trial [6·5% increase in peak power output (PPO)]; there was no difference in the cardiovascular, lactate or catecholamine response to the two cycle trials. cTnI was not significantly elevated from baseline through recovery (Trial 1: 0·06 ± 0·04 ng ml(-1) , 0·05 ± 0·04 ng ml(-1) , 0·03 ± 0·02 ng ml(-1) ; Trial 2: 0·02 ± 0·04 ng ml(-1) , 0·04 ± 0·03 ng ml(-1) , 0·05 ± 0·06 ng ml(-1) ) in either trial. Very small within subject changes were not significantly correlated between the two trials (r = 0·06; P>0·05). Subsequently, short duration, high intensity exercise does not elicit a clinically relevant response in cTnI and any small alterations likely reflect the underlying biological variability of cTnI measurement within the participants.

The aim of this study was to identify hypertension (HT) in karate competitors (KCs) in high intensity exercise. Values were compared with an exercise control group (EC). The 84 subjects were randomly divided into two groups: KC and EC. Resting blood pressure (BP) was measured the day before and immediately precompetition. A further three measurements were taken postexercise for all subjects at 1-, 2-, and 8- minute intervals. At rest, day one, mean BP of KC was 134/84 ± 3/2 mmHg vs. EC, 124/72 ± 1/2 mmHg and on day 2, was 141/79 ± 3/2 mmHg vs. EC, 125/72 ± 1/2 mmHg, respectively. Eight minutes postcompetition, BP of KCs was 140/77 ± 2/1 mmHg vs. EC 135/75 ± 2/1 mmHg. High blood pressure (HBP) was recorded in 60.5% of KCs on day 2, and essential HT that required medical therapy was subsequently diagnosed in 5% of KCs. Five percent of EC also had HBP, but subsequent medical examination reported normal values.

Background: Since 1984 UK citizens have been advised to reduce total dietary fat intake to 30% of total energy and saturated fat intake to 10%. The National Institute of Clinical Excellence [NICE] suggests a further benefit for Coronary Heart Disease [CHD] prevention by reducing saturated fat [SFA] intake to 6% - 7% of total energy and that 30,000 lives could be saved by replacing SFAs with Polyunsaturated fats [PUFAs]. Methods: 20 volumes of the Seven Countries Study, the seminal work behind the 1984 nutritional guidelines, were assessed. The evidence upon which the NICE guidance was based was reviewed. Nutritional facts about fat and the UK intake of fat are presented and the impact of macronutrient confusion on public health dietary advice is discussed. Findings: The Seven Countries study classified processed foods, primarily carbohydrates, as saturated fats. The UK government and NICE do the same, listing biscuits, cakes, pastries and savoury snacks as saturated fats. Processed foods should be the target of public health advice but not natural fats, in which the UK diet is deficient. With reference to the macro and micro nutrient composition of meat, fish, eggs, and dairy foods the article demonstrates that dietary trials cannot change one type of fat for another in a controlled study. Interpretation: The evidence suggests that processed food is strongly associated with the increase in obesity, diabetes, CHD, and other modern illness in our society. The macro and micro nutrients found in meat, fish, eggs and dairy products, are vital for human health and consumption of these nutritious foods should be encouraged.

The standard model of the Universe has it evolving from a concentrated uniform high energy density through phases of decreasing density and increasing components into the present dispersed system of galaxies. Observers use various Information channels to measure and define the parameters governing the expanding Universe. The more noise, uncertainty or error corrupting the signal the less the channel's maximum possible rate of information, the capacity. In the present era, the luminosity of galaxies is taken as the signal which is much larger than the noise of the CMBR. The standard model is applied with constituents and channel capacity examined for each main phase. Inflation occurs in the earliest Universe with constant Planck energy density and an equation of state similar to that of Dark Energy, Davies (2015). At the initial Planck time, the solution requires minimum input parameters and thus a minimum of Information is necessary. Estimates yield similar information rates from the earliest Inflation to the present era, thereby implying conservation of Information Capacity., Essay written for the Gravity Research Foundation 2016 Awards for Essays on Gravitation Submitted 30 March 2016

BACKGROUND The metabolic vasodilator mediating postexercise hypotension (PEH) is poorly understood. Recent evidence suggests an exercise-induced reliance on pro-oxidant-stimulated vasodilation in normotensive young human subjects, but the role in the prehypertensive state is not known. METHODS Nine prehypertensives (mean arterial pressure (MAP), 106 ± 5 mm Hg; 50 ± 10 years old) performed 30 minutes of cycle exercise and a nonexercise trial. Arterial distensibility was characterized by simultaneously recording upper- and lower-limb pulse wave velocity (PWV) via oscillometry. Systemic vascular resistance and conductance were determined by MAP/Q and Q/MAP, respectively. Venous blood was assayed for indirect markers of oxidative stress (lipid hydroperoxides (LOOH); spectrophotometry), plasma nitric oxide (NO) and S-nitrosothiols (fluorometry), atrial natriuretic peptide (ANP), and angiotensin II (ANG-II) (radioimmunoassay). RESULTS Exercise reduced MAP (6mm Hg) and vascular resistance (15%) at 60 minutes after exercise, whereas conductance was elevated (20%) (P < 0.05). The hypotension resulted in a lower MAP at 60 and 120 minutes after exercise compared with nonexercise (P < 0.05). Upper-limb PWV was also 18% lower after exercise compared with baseline (P < 0.05). Exercise increased LOOH coincident with the nadir in hypotension and vascular resistance but failed to affect plasma NO or S-nitrosothiols. Exercise-induced increases in LOOH were related to ANG-II (r = 0.97; P < 0.01) and complemented by elevated ANP concentrations. CONCLUSIONS These data indicate attenuated vascular resistance after exercise with increased oxidative stress and unchanged NO. Whether free radicals are obligatory for PEH requires further investigation, although it seems that oxidative stress occurs during the hyperemia underlying PEH.

The non-therapeutic use of androgenic anabolic steroids (AAS) is associated with sudden cardiac death. Despite this, there is no proposed mechanism by which this may occur. Signal-averaged ECG (SAECG) allows the assessment of cardiac electrical stability, reductions of which are a known risk factor for cardiac arrhythmias. The aim of the present study was to examine cardiac electrical stability using SAECG in a group (n = 15) of long-term AAS users (AAS use 21.3 ± 3.1 years) compared with a group (n = 15) of age-matched weight lifters (WL) and age-matched sedentary controls [C (n = 15)]. AS, WL and C underwent SAECG analysis at rest and following an acute bout of exercise to volitional exhaustion. SAECGs were analyzed using a 40 Hz filter and were averaged over 200 beats. Results indicate a non-significant trend for increased incidence of abnormal SAECG measures at rest in AS (P = 0.55). However, AS demonstrated a significantly higher incidence of abnormalities of SAECG following exercise than C or WL (P < 0.05). In conclusion, the higher incidence of abnormal SAECG measurements immediately post-exercise in the AAS group places them at a greater risk of sudden death. The present study provides a strong contraindication to the use of AAS.

This study investigated the effect of repeated bouts of short-term, high-intensity cycling exercise on the salivary cortisol, testosterone and immunoglobulin (A) concentrations of 15-16 year old boys. Seventeen apparently healthy schoolchildren (aged 15.5 +/- 0.4 years) participated in this study. All participants completed 6 x 8 s sprints, interspersed with 30 s recovery intervals on a cycle ergometer. Using the passive drool method, salivary samples were taken before, and 5 min after, exercise. The group mean for peak power output was 723.1 +/- 180.3 s. There were significant changes (por = 0.05) in both SalT and SalC, 5 min after completing 6 x 8 s cycle sprints. No significant differences (p0.05) were recorded for SIg(A). The increases in SalT and SalC reported in this study confirm that repeated bouts of short-term, high-intensity exercise produces significant physiological hormonal responses in adolescent boys, but does not affect mucosal immune function.

Michael R Graham1, Peter Evans2, Bruce Davies1, Julien S Baker11Health and Exercise Science Research Unit, Faculty of Health Sport and Science, University of Glamorgan, Pontypridd, Wales, United Kingdom; 2Royal Gwent Hospital, Newport, Gwent, United KingdomAbstract: Blood pressure (BP) measurements provide information regarding risk factors associated with cardiovascular disease, but only in a specific artery. Arterial stiffness (AS) can be determined by measurement of arterial pulse wave velocity (APWV). Separate from any role as a surrogate marker, AS is an important determinant of pulse pressure, left ventricular function and coronary artery perfusion pressure. Proximal elastic arteries and peripheral muscular arteries respond differently to aging and to medication. Endogenous human growth hormone (hGH), secreted by the anterior pituitary, peaks during early adulthood, declining at 14% per decade. Levels of insulin-like growth factor-I (IGF-I) are at their peak during late adolescence and decline throughout adulthood, mirror imaging GH. Arterial endothelial dysfunction, an accepted cause of increased APWV in GH deficiency (GHD) is reversed by recombinant human (rh) GH therapy, favorably influencing the risk for atherogenesis. APWV is a noninvasive method for measuring atherosclerotic and hypertensive vascular changes increases with age and atherosclerosis leading to increased systolic blood pressure and increased left ventricular hypertrophy. Aerobic exercise training increases arterial compliance and reduces systolic blood pressure. Whole body arterial compliance is lowered in strength-trained individuals. Homocysteine and C-reactive protein are two infl ammatory markers directly linked with arterial endothelial dysfunction. Reviews of GH in the somatopause have not been favorable and side effects of treatment have marred its use except in classical GHD. Is it possible that we should be assessing the combined effects of therapy with rhGH and rhIGF-I? Only multiple intervention studies will provide the answer.Keywords: arterial pulse, wave velocity, arterial stiffness, growth hormone, insulin-like growth factor, physiology

Michael R Graham1, Peter Evans2, Bruce Davies1, Julien S Baker11Health and Exercise Science Research Unit, Faculty of Health Sport and Science, University of Glamorgan, Pontypridd, Wales, United Kingdom; 2Royal Gwent Hospital, Newport, Gwent, United KingdomAbstract: The nontherapeutic use of prescription medicines by individuals involved in sport is increasing. Anabolic-androgenic steroids (AAS) are the most widely abused drug. Much of our knowledge of the psychological and physiological effects of human growth hormone (hGH) and insulin has been learned from deficiency states. As a consequence of the Internet revolution, previously unobtainable and expensive designer drugs, particularly recombinant human growth hormone (rhGH) and insulin, have become freely available at ridiculously discounted prices from countries such as China and are being abused. These drugs have various physiological and psychological effects and medical personnel must become aware that such prescription medicine abuse appears to be used not only for performance and cosmetic reasons, but as a consequence of psychological pre-morbidity.Keywords: AAS, cosmesis, growth hormone, insulin, performance, strength

The purpose of this study was to compare power outputs, and blood concentrations of lipid hydroperoxides (LH), malondialdehyde (MDA) and lactate ((La - ) B ) following 30s of maximal cycle ergometry when resistive forces were derived from total-body mass (TBM) or fat-free mass (FFM). Differences (P < 0.05) in peak power output (PPO), pedal velocity (PV) and resistive forces (RF) were observed when the TBM and FFM protocols were compared (953 ± 114 W vs 1020 ± 134 W ; 134 ± 8 rpm vs 141 ± 7 rpm ; 6 ± 1 kg vs 5 ± 1 kg respectively). LH and MDA concentrations increased immediately post exercise during the TBM protocol only (P < 0.05) and decreased 24 h post exercise. Alpha- tocopherol and uric acid concentrations decreased immediately post exercise for both protocols (P < 0.05) and increased 24 h later (P < 0.05). The results of the study suggest that greater power outputs are obtainable with significantly less oxi- dative stress when resistive forces reflect FFM as opposed to TBM.

Objectives National dietary guidelines were introduced in 1977 and 1983, by the USA and UK governments, respectively, with the ambition of reducing coronary heart disease (CHD) mortality by reducing dietary fat intake. A recent systematic review and meta-analysis by the present authors, examining the randomised controlled trial (RCT) evidence available to the dietary committees during those time periods, found no support for the recommendations to restrict dietary fat. The present investigation extends our work by re-examining the totality of RCT evidence relating to the current dietary fat guidelines. Methods A systematic review and meta-analysis of RCTs currently available, which examined the relationship between dietary fat, serum cholesterol and the development of CHD, was undertaken. Results The systematic review included 62 421 participants in 10 dietary trials: 7 secondary prevention studies, 1 primary prevention and 2 combined. The death rates for all-cause mortality were 6.45% and 6.06% in the intervention and control groups, respectively. The risk ratio (RR) from meta-analysis was 0.991 (95% CI 0.935 to 1.051). The death rates for CHD mortality were 2.16% and 1.80% in the intervention and control groups, respectively. The RR was 0.976 (95% CI 0.878 to 1.084). Mean serum cholesterol levels decreased in all intervention groups and all but one control group. The reductions in mean serum cholesterol levels were significantly greater in the intervention groups; this did not result in significant differences in CHD or all-cause mortality. Conclusions The current available evidence found no significant difference in all-cause mortality or CHD mortality, resulting from the dietary fat interventions. RCT evidence currently available does not support the current dietary fat guidelines. The evidence per se lacks generalisability for population-wide guidelines.

Epidemiological studies of anti-obesity medicines depict short-term success, but long-term contraindication and failure. The health and fitness industry demonstrates an exponential increase in banned or withdrawn medicines. Everyone is in pursuit of the “golden bullet”. How effective are the older prescription medicines such as orlistat? History has demonstrated retrospectively that the “fen-phen” prescriptive phenomenon cost countless lives and billions of dollars in compensation. New medicines and lower doses of older failed medications to combat the obesity pandemic are being researched. A complete re-assessment of what is available and what is worthwhile is required.

Prescription medicines are progressively being abused to augment appearance. Information gleaned from the sporting arena is being extrapolated to the domestic market merely because of the increase in obesity in the population. The list of the types of drug use and their metabolic effects is diverse and includes drugs that are believed to increase the basal metabolic rate (clenbuterol, ephedrine, recombinant human growth hormone, insulin-like growth factor-1 Long arm 3, thyroxine) prevent fat absorption (orlistat) or affect neurochemical modulators (sibutramine). Such drugs if used indiscriminately even with medical supervision, can cause serious long-term sequelae and call their use into question?

The purpose of this study was to compare the exercise performance and postexercise recovery of 8 male subjects using four different maximal high-intensity intermittent cycle ergometry protocols. Resistive forces were calculated by multiplying fat-free mass (FFM) or total-body mass (TBM) by 0.75 g.kg(-1). Rest periods between successive sprints were 30 s (R30) or 60 s (R60) duration. Higher pedal velocities were recorded using FFM as opposed to TBM (P0.05). Rest intervals of R60 (P0.05) influenced the peak power output values (903.88 +/- 184.01 W; TBM/R30 vs. 852.98 +/- 209.68 W; FFM/R30 vs. 965.64 +/- 177.48 W; TBM/R60 vs. 968.66 +/- 173.70 W; FFM/R60). Diastolic blood pressure (DBP) was lower than resting values (P0.05) postexercise in all protocols. These findings demonstrate that power outputs rely on resistive force selection and recovery duration, and that high-intensity exercise may provide an alternative to aerobic activity in the management of hypertension.

This study examined the dietar y habits of Welsh 12—13 year olds. A cohor t of 84 boys and 81 girls, age 12.9 SD 0.3 years; body mass 51.3 SD 12.6kg; and stature 1.54 SD 0.08m, completed a food frequency questionnaire and seven-day food diary. Mean daily kilocalories (kcal/d), and percentages of total fat, saturated fat, carbohydrate, and protein, as well as fibre intake were calculated. The mean daily intake of total fat for this cohor t was 34.7 percent, for saturated fat the value was 13.8 percent. The mean daily intake of carbohydrate and protein were 50.5 and 14.9 percent, respectively. The schoolchildren in this study repor ted a mean daily fibre intake of 12.3g. The absolute intake of kilocalories was significantly greater ( p ≤ 0.05) among boys than girls, but no other significant differences were repor ted. This study revealed that the diets of Welsh 12—13 year olds exceeded recommendations for fat, while at the same time did not meet the recommendations for fibre, and particularly fruit and vegetable intake. Our data indicated that, despite schools offering a range of healthy lunchtime foods, young people continue to consume an energy-dense and nutrient-poor diet, both at school and at home.

A Monark cycle ergometer is used in physiological studies to measure work done and power. In this paper, the accuracy of a Monark rope-braked cycle ergometer was examined for a Wingate anaerobic test (WAnT). The traditional method of determining brake torque fails to take into account rope-brake theory and, as the brake torque is used to determine the moment of inertia of the flywheel, a second error is introduced into the calculation to determine the work done or power. In this study, the rope tensions were measured to determine the actual brake torque. A deceleration test was carried out to determine the moment of inertia of the system. The work done by subjects of different masses was calculated for various accelerations and it was found that the traditional calculations overestimate work done and power by between 12% and 14.7%.

PurposeThe purpose of this study is to biomedically assess biscuits designed to reduce selected risk factors for coronary heart disease, in particular serum homocysteine and glucose.Design/methodology/approachIn this study, one of the countries leading jam sandwhich biscuits was significantly modified, with particular attention being paid to sugar, fat and salt concentration. A traditional biscuit was converted to a functional food by the addition of vitamin B12, Folic Acid, Vitamin C and Prebiotic fibre, while reducing salt and sugar.FindingsThe results obtained from a clinical trial demonstrated that serum homocysteine and blood glucose were significantly decreased (P < 0.05) when the modified product and the traditional biscuit were compared. These findings confirm that a health promoting biscuit can be produced commercially, and have similar organoleptic properties as the standard high fat, high sugar and salt product.Practical implicationsThese findings could have significant implications to the biscuit industry, as producers of products traditionally associated with poor health. This study shows that biscuit formulations can be modified significantly, and that the resultant dough yield biscuits which can be produced under commercial conditions, be organoleptically acceptable and reduce risk factors associated with coronary heart disease.Originality/valueMoving into the twenty‐first century, there is no reason why biscuit consumption should be associated with poor health. Recipe and processing modifications are possible, thanks to new and innovative raw materials and an understanding of dough rheology.

The purpose of this study was to compare power outputs and blood lactate concentrations ([La-]B) following 30 s of maximal cycle ergometry when resistive forces were derived from total-body mass (TBM) or fat-free mass (FFM). Differences (P < 0.05) in peak power output (PPO), pedal velocity (PV) and resistive forces (RF) were observed when the TBM and FFM protocols were compared (953 +/- 114 W vs. 1020 +/- 134 W; 134 +/- 8 rpm vs. 141 +/- 7 rpm; 6 +/- 1 kg vs. 5 +/- 1 kg, respectively). Blood lactate values ([La-]B) increased (P < 0.01) postexercise for both protocols and were significantly greater for TBM (10.6 +/- 1.2 mmol.l-1 vs 11.6 +/- 1.1 mmol.l-1, P < 0.05). These findings indicate that the FFM resistive force protocol may maximise adenosinotriphosphate-phosphocreatine (ATP-PC) utilisation with smaller contributions from anaerobic glycolysis when compared with TBM. These results may have important implications in the assessment of high intensity exercise performance.

The purpose of this study was to examine relationships between aerobic fitness (AF), fatness, and coronary-heart-disease (CHD) risk factors in 12- to 13-year-olds. The data were obtained from 208 schoolchildren (100 boys; 108 girls) ages 12.9 ± 0.3 years. Measurements included AF, indices of obesity, blood pressure, blood lipids and lipoproteins, fibrinogen, homocysteine, and C-reactive protein. An inverse relationship was found between AF and fatness (p < .05). Fatness was related to a greater number of CHD risk factors than fitness was (p < .05). Further analysis revealed fatness to be an independent predictor of triglyceride and blood-pressure levels (p < .05). Our findings indicate that, for young people, fatness rather than fitness is independently related to CHD risk factors.

Pumps are critical components of many industrial processes. Although they vary in size, depending on the application, their operating principles and performance parameters are similar across generic families. Large industrial positive displacement (P.D.) pumps, primarily used in mining, oil and gas industries, deliver significant amounts of flow coupled with very high pressures. However, increasing energy costs and sustainability concerns demand systems re-design to improve their efficiency. Most established forms of PD pumps have duty cycles fixed by the movement of spring loaded valves. One approach to increase their energy efficiency could be to dynamically vary the movement of these valves. To test this hypothesis and quantify any potential benefits a computational model is required. This paper introduces modelling technique used to analytically describe a multi-cylinder positive displacement pump. A hybrid modelling approach is described which incorporates analytical relationships, the results of CFD simulation and experimental values. Results show how different valve actuation responses affect the overall flow rate of the pump. The results presented in the paper clearly indicate future development steps for improved control of positive displacement pumps.

Central fatigue, such as that found in chronic fatigue syndrome, is a state in which cognition and action require increasing effort and performance is impaired without evidence for reduced peripheral motor responsiveness. Previous studies identified functional changes in subcortical regions in patients who experience central fatigue but did not address neural correlates of the subjective experience of fatigue.This study investigated responses to acute tryptophan feeding (after administration of 30 mg/kg body mass) using functional magnetic resonance imaging to investigate neural correlates of central fatigue during a cognitively demanding exercise, the counting Stroop task.In a double-blind, cross-over study, eight subjects ingested L: -tryptophan (Trp) or placebo (Plac) on two separate test days. Neutral (N) and interference (I) Stroop tasks were carried out.Plasma-free tryptophan (p[FT]) increased tenfold after L: -Trp administration (P0.01). Although reaction times were longer after Trp (mean+/-SD, Plac-Neut 669 +/- 163 ms, I 715 +/- 174 ms, P0.01; Trp-Neut 712 +/- 193 ms, I 761 +/- 198 ms, P0.05), the Stroop effect was not significantly different between Plac and Trp. L: -Trp administration was associated with relatively decreased activation in regions, including the left postcentral, angular, inferior frontal, and the lateral orbital gyri and the inferior frontal sulcus relative to Plac. Relatively increased activation was found after Trp in the left precuneus and in the posterior cingulate gyrus.Thus, Trp administration before the Stroop task caused distributed functional changes in primary sensory and in multimodal neocortex, including changes in a brain region, the activity of which has been shown previously to vary with conscious awareness (precuneus). Previous reports suggest that primary mechanisms of central fatigue may be predominantly subcortical. The present results demonstrate that neocortical activity changes are also found. Whether this activity contributes to the primary mechanisms underlying central fatigue or not, the neocortical activity changes may provide an index of the conscious experience.

The purpose of this study was to compare the maximal exercise performance of overweight and obese subjects during friction braked cycle ergometry of 10 s duration when resistive forces reflected total-body mass (TBM) or fat-free mass (FFM). Subjects were assigned at random to either protocol. Eleven healthy male university students (age 22.3 +/- 2 yrs, body fat 27.1 +/- 2%) participated in the study. Differences (P < 0.01) in peak power output (PPO) were found between TBM and FFM (1029 +/- 98 W TBM vs. 1397 +/- 146 W FFM). The findings of this study suggest that greater peak power outputs are obtainable when resistive forces reflect FFM as opposed to TBM. The results have implications that relate to the pathology of disease, related clinical examinations, and exercise prescription.

It is well established that tobacco smokers have reduced levels of monoamine oxidase activities both in the brain and peripheral organs. Furthermore, extensive evidence suggests that smokers are less prone to develop Parkinson's disease. These facts, plus the observation that inhibition of monoamine oxidase B protects against the parkinsonian inducing effects of the nigrostriatal neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, have prompted studies to identify monoamine oxidase inhibitors in the tobacco plant and tobacco cigarette smoke. Our previous efforts on cured tobacco leaf extracts have led to the characterization of 2,3,6-trimethyl-1,4-naphthoquinone, a non-selective monoamine oxidase inhibitor, and farnesylacetone, a selective monoamine oxidase B inhibitor. We now have extended these studies to tobacco smoke constituents. Fractionation of the smoke extracts has confirmed and extended the qualitative results of an earlier report [J. Korean Soc. Tob. Sci.1997, 19, 136] demonstrating the inhibitory activity of the terpene trans,trans-farnesol on rat brain MAO-B. In the present study, K(i) values for the inhibition of human, baboon, monkey, dog, rat, and mouse liver MAO-B have been determined. Noteworthy is the absence of inhibitory effects on human placental MAO-A and beef liver MAO-B. A limited structure-activity relationship study of analogs of trans,trans-farnesol is reported. Although the health hazards associated with the use of tobacco products preclude any therapeutic opportunities linked to smoking, these results suggest the possibility of identifying novel structures of compounds that could lead to the development of neuroprotective agents.

This study compares the instrumentation and analysis techniques used when determining the power expended pedalling a rope-braked ergometer manufactured by Monark (Sweden) during a low intensity test. Power values were generated by eight subjects. The instrumentation consisted of load cells to measure the rope brake forces, a tachometer to measure the flywheel velocity and instrumented pedal cranks manufactured by Schoberer Rad Messtechnik (SRM). The subjects pedalled a rope-braked ergometer at 60 rev min-1, against a resistance of 3 kg, for 5 minutes. Three different measurements of the mean power were recorded and these were compared with the value given by Monark. The SRM cranks provided two sets of results using different software packages supplied with the cranks. SRM standard software is used for taking measurements during training and cycle races over long time periods. An additional piece of software is provided by SRM called Ptnew, which gives readings of torque and pedal cadence over periods up to 30 seconds. Using the values supplied by Monark each subject generated 180 W of power. The mean power for the eight subjects, measured using the SRM cranks, was 170.36 W (SD 4.11) using the alternative SRM software (Ptnew) over a 30 second period and 173.68 W (SD 2.21) using the standard SRM software. From the direct measurement of the brake forces and flywheel velocity the mean power across the eight subjects was 148.90 W (SD 5.89). The SRM cranks measure the input power, whereas the direct measurement system measures the power output excluding mechanical losses. These values give a figure for the mechanical efficiency for the roped-braked ergometer of 88%. It was found that Monark overestimates the power generated by the subjects when compared with both the SRM systems and the direct measurement instrumentation.

The cycle ergometer is one of the main tools used by physiologists in studies involving the measurement of work or power against physiological criteria. The current mechanical analysis of a Monark 824E rope-braked ergometer is based on a simplified approach. In this study a detailed analysis of the system is adopted to increase understanding. The mechanics of the ergometer flywheel are explained using data generated experimentally and the detailed components of the values of work that comprise the total work done by a subject are discussed. The total work done by a subject in 2.5 minutes at a speed of 60 rpm against a brake mass of 3 kg was 23,034 J compared with the value of 27,000 J that normally would be attributed using the traditional calculations. This 15% difference is mainly due to the incorrect assumption that the brake load is the force due to the basket mass.