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The Development and Study of High-Position Resolution (50 micron) RPCs for Imaging X-rays and UV photons

Nowadays, commonly used Resistive Plate Chambers (RPCs) have counting rate capabilities of ~10E4Hz/cm2 and position resolutions of ~1cm. We have developed small prototypes of RPCs (5x5 and 10x10cm2) having rate capabilities of up to 10E7Hz/cm2 and position resolutions of 50 micron("on line" without application of any treatment method like "center of gravity"). The breakthrough in achieving extraordinary rate and position resolutions was only possible after solving several serious problems: RPC cleaning and assembling technology, aging, spurious pulses and afterpulses, discharges in the amplification gap and along the spacers. High-rate, high-position resolution RPCs can find a wide range of applications in many different fields, for example in medical imaging. RPCs with the cathodes coated by CsI photosensitive layer can detect ultraviolet photons with a position resolution that is better than ~30 micron. Such detectors can also be used in many applications, for example in the focal plane of high resolution vacuum spectrographs or as image scanners.Comment: 6 pages, 5 figures, other comment

Serum Concentrations of Myostatin and Myostatin-Interacting Proteins do not differ between young and Scarcopenic elderly men

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Awareness of hypertension and depressive symptoms: a cross-sectional study in a primary care population

Objective: To investigate the association of hypertension awareness and depressive symptoms, and to analyse factors predisposing aware hypertensives to depressive symptoms.Design: Cross-sectional study in a primary care population.Setting: Cardiovascular risk factor survey in two semi-rural towns in Finland.Subjects: Two thousand six hundred seventy-six middle-aged risk persons without an established cardiovascular or renal disease or type 2 diabetes.Main outcome measures: Depressive symptoms, previous and new diagnosis of hypertension.Results: Hypertension was diagnosed in 47.9% of the subjects, of whom 34.5% (442/1 282) had previously undetected hypertension. Depressive symptoms were reported by 14% of the subjects previously aware of their hypertension, and by 9% of both unaware hypertensives and normotensive subjects. In the logistic regression analysis, both the normotensive (OR 0.62, 95% CI 0.45–0.86) (p = 0.0038) and the unaware hypertensive subjects (OR 0.54, 95% CI 0.35–0.84) (p = 0.0067) had lower risk for depressive symptoms than the previously diagnosed hypertensives. Among these aware hypertensives, female gender (OR 3.61, 95% CI 2.06–6.32), harmful alcohol use (OR 2.55, 95% CI 1.40–4.64) and obesity (OR 2.50, 95% CI 1.01–6.21) predicted depressive symptoms. Non-smoking (OR 0.57, 95% Cl 0.33–0.99) and moderate leisure-time physical activity compared to low (OR 0.53, 95% CI 0.33–0.84) seemed to buffer against depressive symptoms.Conclusion: Depressive symptoms are common in hypertensive persons even without comorbidities, if the person is already aware of his/her hypertension. Many modifiable, lifestyle associated factors may contribute to the association of hypertension and depressive symptoms.</p