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Carbon stable isotope analysis of cereal remains as a way to reconstruct water availability: preliminary results
Reconstructing past water availability, both as rainfall and irrigation, is important to answer questions about the way society reacts to climate and its changes and the role of irrigation in the development of social complexity. Carbon stable isotope analysis of archaeobotanical remains is a potentially valuable method for reconstructing water availability. To further define the relationship between water availability and plant carbon isotope composition and to set up baseline values for the Southern Levant, grains of experimentally grown barley and sorghum were studied. The cereal crops were grown at three stations under five different irrigation regimes in Jordan. Results indicate that a positive but weak relationship exists between irrigation regime and total water input of barley grains, but no relationship was found for sorghum. The relationship for barley is site-specific and inter-annual variation was present at Deir âAlla, but not at Ramtha and Khirbet as-Samra
Nutritional strategies of high level natural bodybuilders during competition preparation
Background
Competitive bodybuilders employ a combination of resistance training, cardiovascular exercise, calorie reduction, supplementation regimes and peaking strategies in order to lose fat mass and maintain fat free mass. Although recommendations exist for contest preparation, applied research is limited and data on the contest preparation regimes of bodybuilders are restricted to case studies or small cohorts. Moreover, the influence of different nutritional strategies on competitive outcome is unknown.
Methods
Fifty-one competitors (35 male and 16 female) volunteered to take part in this project. The British Natural Bodybuilding Federation (BNBF) runs an annual national competition for high level bodybuilders; competitors must qualify by winning at a qualifying events or may be invited at the judgeâs discretion. Competitors are subject to stringent drug testing and have to undergo a polygraph test. Study of this cohort provides an opportunity to examine the dietary practices of high level natural bodybuilders. We report the results of a cross-sectional study of bodybuilders competing at the BNBF finals. Volunteers completed a 34-item questionnaire assessing diet at three time points. At each time point participants recorded food intake over a 24-h period in grams and/or portions. Competitors were categorised according to contest placing. A âplacedâ competitor finished in the top 5, and a âNon-placedâ (DNP) competitor finished outside the top 5. Nutrient analysis was performed using Nutritics software. Repeated measures ANOVA and effect sizes (Cohenâs d) were used to test if nutrient intake changed over time and if placing was associated with intake.
Results
Mean preparation time for a competitor was 22â±â9 weeks. Nutrient intake of bodybuilders reflected a high-protein, high-carbohydrate, low-fat diet. Total carbohydrate, protein and fat intakes decreased over time in both male and female cohorts (P <â0.05). Placed male competitors had a greater carbohydrate intake at the start of contest preparation (5.1 vs 3.7 g/kg BW) than DNP competitors (d =â1.02, 95% CI [0.22, 1.80]).
Conclusions
Greater carbohydrate intake in the placed competitors could theoretically have contributed towards greater maintenance of muscle mass during competition preparation compared to DNP competitors. These findings require corroboration, but will likely be of interest to bodybuilders and coaches.
Keywords
BodybuildersCaloriesCompetitionContest preparationDietingEnergy restrictionNaturalNutritionSupplementationPhysiqu
Molecular and cellular mechanisms underlying the evolution of form and function in the amniote jaw.
The amniote jaw complex is a remarkable amalgamation of derivatives from distinct embryonic cell lineages. During development, the cells in these lineages experience concerted movements, migrations, and signaling interactions that take them from their initial origins to their final destinations and imbue their derivatives with aspects of form including their axial orientation, anatomical identity, size, and shape. Perturbations along the way can produce defects and disease, but also generate the variation necessary for jaw evolution and adaptation. We focus on molecular and cellular mechanisms that regulate form in the amniote jaw complex, and that enable structural and functional integration. Special emphasis is placed on the role of cranial neural crest mesenchyme (NCM) during the species-specific patterning of bone, cartilage, tendon, muscle, and other jaw tissues. We also address the effects of biomechanical forces during jaw development and discuss ways in which certain molecular and cellular responses add adaptive and evolutionary plasticity to jaw morphology. Overall, we highlight how variation in molecular and cellular programs can promote the phenomenal diversity and functional morphology achieved during amniote jaw evolution or lead to the range of jaw defects and disease that affect the human condition
Leadership and style in the French Fifth Republic:Nicolas Sarkozyâs presidency in historical and cultural perspective
This article contributes to the body of the developing theoretical research in leadership and presidential studies by adding analysis of what I have termed âcomportmental styleâ as a factor in leader/follower relations. Within institutionalism and the wider structure/agency debate in political science, one of the challenges as regards the study of leadership is to identify factors that offer scope to or else militate against leadersâ performance. The comportmental style of Nicolas Sarkozy (President of the French Republic 2007â2012), deployed in the context of the â changing â institution of the presidency, was a major factor in his extreme unpopularity, and contributed to his defeat in 2012. What this tells us about the nature of the changing French presidency and the role of style will be discussed in the conclusion
The effect of acupuncture duration on analgesia and peripheral sensory thresholds
<p>Abstract</p> <p>Background</p> <p>Acupuncture provides a means of peripheral stimulation for pain relief. However, the detailed neuronal mechanisms by which acupuncture relieves pain are still poorly understood and information regarding optimal treatment settings is still inadequate. Previous studies with a short burst of unilateral electroacupuncture (EA) in the Tendinomuscular Meridians (TMM) treatment model for pain demonstrated a transient dermatomally correlated bilateral analgesic effect with corresponding peripheral modality-specific sensory threshold alterations. However, the impact of EA duration on the analgesic effect in this particular treatment model is unknown. To obtain mechanistically and clinically important information regarding EA analgesia, this current prospective cross-over study assesses the effects of EA duration on analgesia and thermal sensory thresholds in the TMM treatment model.</p> <p>Methods</p> <p>Baseline peripheral sensory thresholds were measured at pre-marked testing sites along the medial aspects (liver and spleen meridians) of bilateral lower extremities. A 5-second hot pain stimulation was delivered to the testing sites and the corresponding pain Visual Analog Scale (VAS) scores were recorded. Three different EA (5Hz) stimulation durations (5, 15 and 30 minutes) were randomly tested at least one week apart. At the last 10 seconds of each EA session, 5 seconds of subject specific HP stimulation was delivered to the testing sites. The corresponding pain and EA VAS scores of de qi sensation (tingling) during and after the EA were recorded. The measurements were repeated immediately, 30 and 60 minutes after the EA stimulation. A four-factor repeat measures ANOVA was used to assess the effect of stimulation duration, time, location (thigh vs. calf) and side (ipsilateral vs. contralateral) of EA on sensory thresholds and HP VAS scores.</p> <p>Results</p> <p>A significant (P < 0.01) main effect of time and location with warm, cold and hot pain thresholds at the four testing sites without any significant difference in duration effect was observed. Similar time and location effects were observed with HP VAS with the longer durations (15 and 30 minutes) of stimulation showed a slower onset, but a more sustainable bilateral analgesic benefit than the short stimulation duration (5 minutes). The 15-minute stimulation resulted in an earlier onset of analgesic effect than the 30-minute stimulation paradigm.</p> <p>Conclusion</p> <p>Longer durations of EA stimulation provide a more sustainable analgesic benefit to hot noxious stimulation than a shorter duration of stimulation. The increase of cold threshold with sustained warm threshold temperature elevation as observed in the longer durations of EA suggests that as the duration of EA lengthened, there is a gradual shifting from an initial predominantly spinally mediated analgesic effect to a supraspinally mediated modulatory mechanism of thermal pain. The 15-minute stimulation appeared to be the optimal setting for treating acute pain in the lower extremities.</p
A Nutrition and Conditioning Intervention for Natural Bodybuilding Contest Preparation: Case Study.
Bodybuilding competitions are becoming increasingly popular. Competitors are judged on their aesthetic
appearance and usually exhibit a high level of muscularity and symmetry and low levels of body fat. Commonly used techniques to improve physique during the preparation phase before competitions include dehydration, periods of prolonged fasting, severe caloric restriction, excessive cardiovascular exercise and inappropriate use of diuretics and anabolic steroids. In contrast, this case study documents a structured nutrition and conditioning
intervention followed by a 21 year-old amateur bodybuilding competitor to improve body composition, resting and
exercise fat oxidation, and muscular strength that does not involve use of any of the above mentioned methods.
Over a 14-week period, the Athlete was provided with a scientifically designed nutrition and conditioning plan that
encouraged him to (i) consume a variety of foods; (ii) not neglect any macronutrient groups; (iii) exercise regularly
but not excessively and; (iv) incorporate rest days into his conditioning regime. This strategy resulted in a body
mass loss of 11.7 kgâs, corresponding to a 6.7 kg reduction in fat mass and a 5.0 kg reduction in fat-free mass.
Resting metabolic rate decreased from 1993 kcal/d to 1814 kcal/d, whereas resting fat oxidation increased from
0.04 g/min to 0.06 g/min. His capacity to oxidize fat during exercise increased more than two-fold from 0.24 g/min
to 0.59 g/min, while there was a near 3-fold increase in the corresponding exercise intensity that elicited the
maximal rate of fat oxidation; 21% VÌ
O2max to 60% VÌ O2max. Hamstring concentric peak torque decreased (1.7 to 1.5 Nm/kg), whereas hamstring eccentric (2.0 Nm/kg to 2.9 Nm/kg), quadriceps concentric (3.4 Nm/kg to 3.7 Nm/kg) and quadriceps eccentric (4.9 Nm/kg to 5.7 Nm/kg) peak torque all increased. Psychological mood-state (BRUMS scale) was not negatively influenced by the intervention and all values relating to the Athleteâs mood-state remained below average over the course of study. This intervention shows that a structured and scientifically supported nutrition strategy can be implemented to improve parameters relevant to bodybuilding competition and importantly the health of competitors, therefore questioning the conventional practices of bodybuilding preparation
Host plant quality, spatial heterogeneity, and the stability of mite predatorâprey dynamics
Population dynamics models suggest that both the over-all level of resource productivity and spatial variability in productivity can play important roles in community dynamics. Higher productivity environments are predicted to destabilize consumerâresource dynamics. Conversely, greater heterogeneity in resource productivity is expected to contribute to stability. Yet the importance of these two factors for the dynamics of arthropod communities has been largely overlooked. I manipulated nutrient availability for strawberry plants in a multi-patch experiment, and measured effects of overall plant quality and heterogeneity in plant quality on the stability of interactions between the phytophagous mite Tetranychus urticae and its predator Phytoseiulus persimilis. Plant size, leaf N content and T. urticae population growth increased monotonically with increasing soil nitrogen availability. This gradient in plant quality affected two correlates of mite population stability, population variability over time (i.e., coefficient of variation) and population persistence (i.e., proportion of plant patches colonized). However, the highest level of plant quality did not produce the least stable dynamics, which is inconsistent with the âparadox of enrichmentâ. Heterogeneity in plant productivity had modest effects on stability, with the only significant difference being less variable T. urticae densities in the heterogeneous compared to the corresponding homogeneous treatment. These results are generally congruent with metapopulation theory and other models for spatially segregated populations, which predict that stability should be governed largely by relative movement rates of predators and preyârather than patch quality
Political leadership and the politics of performance:France, Syria and the chemical weapons crisis of 2013
This article draws upon developments in UK research on political rhetoric and political performance in order to examine the incident in 2013 when French President François Hollande committed French forces to a US-led punitive strike against Syria, after the use of chemical weapons in a Damascus suburb on 21 August. The US-led retaliation did not take place. This article analyses Hollande's declaration on 27 July and his TV appearance on 15 September. His rhetoric and style are best understood as generic to the nature of the presidential office of the Fifth Republic. The article concludes by appraising how analysis of the French case contributes to the developing literature on rhetoric, celebrity and performance
Perceived barriers and facilitators to mental health help-seeking in young people: a systematic review
<p>Abstract</p> <p>Background</p> <p>Adolescents and young adults frequently experience mental disorders, yet tend not to seek help. This systematic review aims to summarise reported barriers and facilitators of help-seeking in young people using both qualitative research from surveys, focus groups, and interviews and quantitative data from published surveys. It extends previous reviews through its systematic research methodology and by the inclusion of published studies describing what young people themselves perceive are the barriers and facilitators to help-seeking for common mental health problems.</p> <p>Methods</p> <p>Twenty two published studies of perceived barriers or facilitators in adolescents or young adults were identified through searches of PubMed, PsycInfo, and the Cochrane database. A thematic analysis was undertaken on the results reported in the qualitative literature and quantitative literature.</p> <p>Results</p> <p>Fifteen qualitative and seven quantitative studies were identified. Young people perceived stigma and embarrassment, problems recognising symptoms (poor mental health literacy), and a preference for self-reliance as the most important barriers to help-seeking. Facilitators were comparatively under-researched. However, there was evidence that young people perceived positive past experiences, and social support and encouragement from others as aids to the help-seeking process.</p> <p>Conclusions</p> <p>Strategies for improving help-seeking by adolescents and young adults should focus on improving mental health literacy, reducing stigma, and taking into account the desire of young people for self-reliance.</p
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