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Objective The dose-response effects of exercise training on insulin sensitivity, metabolic risk, and quality of life were examined. Methods Sixty-one healthy, sedentary (VO2max: 35 ± 5 ml/kg/min), moderately overweight (BMI: 27.9 ± 1.8), young (age: 29 ± 6 years) men were randomized to sedentary living (sedentary control group; n = 18), moderate (moderate dose training group [MOD]: 300 kcal/day, n = 21), or high (high dose training group [HIGH]: 600 kcal/day, n = 22) dose physical exercise for 11 weeks. Results The return rate for post-intervention testing was 82-94% across groups. Weekly exercise amounted to 2,004 ± 24 and 3,774 ± 68 kcal, respectively, in MOD and HIGH. Cardiorespiratory fitness increased ( P < 0.001) 18 ± 3% in MOD and 17 ± 3% in HIGH, and fat percentage decreased ( P < 0.001) similarly in both exercise groups (MOD: 32 ± 1 to 29 ± 1%; HIGH: 30 ± 1 to 27 ± 1%). Peripheral insulin sensitivity increased ( P < 0.01) (MOD: 28 ± 7%; HIGH: 36 ± 8%) and the homeostasis model assessment of insulin resistance decreased ( P < 0.05) (MOD: -17 ± 7%; HIGH: -18 ± 10%). The number of subjects meeting the criteria of the metabolic syndrome decreased by 78% in MOD ( P < 0.01) and by 80% in HIGH ( P < 0.05). General health assessed by questionnaire increased similarly in MOD ( P < 0.05) and HIGH ( P < 0.01). Conclusions Only minor additional health benefits were found when exercising ∼3,800 as opposed to ∼2,000 kcal/week in young moderately overweight men. This finding may have important public health implications. [ABSTRACT FROM AUTHOR]

The NASA Kepler mission yields an unprecedented amount of data in the form of photometric light curves. Apart from valuable information on exoplanets and stellar pulsations, the light curves contain rotation signals from starspots crossing the stellar disk. These modulations of the light curves are modeled and 105 simulations are carried out to analyze and understand a similar analysis of the Kepler light curves. The periodogram is calculated for each light curve. Under the assumption that the main source of variability at periods >1 day is due to spots, the simulations show that the rotation period can be easily determined for spot lifetimes of 30-60 days, but becomes more unreliable for spots lifetimes of 10-20 days. The amplitude of the periodogram peaks appear to be only weakly dependent on changes in the size of the spots, while the width of the peaks shows no clear change with increasing spot lifetimes (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

SUMMARY An angular momentum and energy-conserving time integration algorithm for rigid body rotation is formulated in terms of the quaternion parameters and the corresponding four-component conjugate momentum vector via Hamilton's equations. The introduction of an extended mass matrix leads to a symmetric set of eight state-space equations of motion. The extra inertial parameter serves as a multiplier on the kinematic constraint, and it is demonstrated that convergence characteristics are improved by selecting this parameter somewhat larger than the inertial moments. External loads enter these equations via the set of momentum equations. Initially, the normalization of the quaternion array is introduced via a Lagrange multiplier. However, this Lagrange multiplier can be expressed explicitly in terms of the gradient of the external load potential, and elimination of the Lagrange multiplier from the final format leaves only an explicit projection applied to the external load potential gradient. An algorithm is developed by forming a finite increment of the Hamiltonian. This procedure identifies the proper selection of increments and mean values, and leads to an algorithm with conservation of momentum and energy. Implementation, conservation properties, and accuracy of the algorithm are illustrated by examples with a flying box and a spinning top. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective To test the hypothesis that there is an association between simple renal cysts and arterial blood pressure (BP). Patients and methods The study comprised a review of the case-notes of 115 patients (mean age 67.7 years, range 31-91) in whom renal cyst(s) was an incidental ultrasonographic finding, and 115 age- and sex-matched control patients. The notes were reviewed without knowledge of the origin or treatment. Results The systolic and diastolic BP were significantly higher in patients with a cyst(s) than in control patients ( P=0.031 and P=0.0034; mean difference 6.9 mmHg and 5.0 mmHg, respectively). In those aged 30-70 years, the presence of one or more simple renal cysts increased the risk of having a diastolic BP ≥95 mmHg from seven in 58 to 17 in 58 patients ( P=0.038). Conclusion The association between simple renal cysts and higher arterial BP probably arises from underlying renal disease causing both. Occasionally it is possible that renal ischaemia caused by cyst expansion, and therefore increased renin release, generates the elevation in BP. If so, methods to identify such cysts should be developed. [ABSTRACT FROM AUTHOR]