We investigate accreting disk systems with polytropic gas in Keplerian motion. Numerical data and partial analytic results show that the self-gravitation of the disk speeds up its rotation -- its ...rotational frequency is larger than that given by the well known strictly Keplerian formula that takes into account the central mass only. Thus determination of central mass in systems with massive disks requires great care -- the strictly Keplerian formula yields only an upper bound. The effect of self-gravity depends on geometric aspects of disk configurations. Disk systems with a small (circa \(10^{-4}\)) ratio of the innermost radius to the outermost disk radius have the central mass close to the upper limit, but if this ratio is of the order of unity then the central mass can be smaller by many orders of magnitude from this bound.
The three different kinds of imidazo2,1-ftheophylline derivatives were synthesized and tested for their CNS activity. A series of alkoxy-alkylamides and amino-alkylamides with basic function, derived ...from 8-benzyl-6,7-dihydroimidazo2,1-ftheophylline-7-carboxylic acid showed stimulating influence on CNS as they increased the locomotor activity (compound
8 and
10) or enhanced amphetamine and apomorphine effects in mice (compounds
3,
4 and
9). Compounds
1,
5,
8–
10 and
12 had anticonvulsant activity in the pentetrazole test;
12 with anellated imidazol-7-on ring (lactam structure) showed sedative properties and antiserotonin effects.
With prevalences ranging from 0.26 to 0.8‰ of all live births tetralogy of Fallot (TOF) is the most common congenital heart disease with primary cyanosis. Due to improvements in surgical techniques, ...nearly all patients can nowadays expect to reach adulthood. After surgical repair, pulmonary regurgitation (PR) occurs in almost every child and is an important contributing factor in long-term morbidity and mortality. Cardiac magnetic resonance imaging is well established for functional assessment and flow measurements and is an ideal tool for serial post-surgical follow-up examinations, as it is non-invasive and does not expose patients to ionizing radiation. The timing of pulmonary valve replacement is crucial as right ventricular (RV) volumes have only proven to normalize when preoperative end-diastolic volumes are <170 ml/m(2) and end-systolic volumes are <85 ml/m(2). After surgical repair up to 15% of patients have residual or recurrent pulmonary artery stenosis. Distal pulmonary branch stenosis can aggravate PR and lead to right heart failure due to combined pressure and volume overload. Therefore, it has to be diagnosed in time and treated by angioplasty with or without stenting.
Cerebral electrical stimulation (CES), born from research on electroanesthesia in the seventies, consists of the application of a pulsating current of small intensity (usually less than 1 mA, and ...below the threshold of perception) through the skull, e.g., in daily 30-min sessions. Claims of biological effectiveness (neurochemical, hormonal and EEG changes, naloxone-reversible analgesia in rats, etc.) and of clinical effectiveness (anxiety, depression, cognitive functions in alcoholics) have often relied on poorly controlled data. A recent controlled study in the treatment of opiate withdrawal has been positive. The present double-blind controlled study compares active CES with sham stimulation in 64 alcohol-dependent males. Over 4 weeks, both treatment groups improved significantly in most aspects. In the active treatment group additional significant improvement was observed in week-end alcohol consumption, and in two psychological measures: depression and stress symptoms index, but not in general drinking behavior.
Accelerating expansion of the Universe is a great challenge for both physics and cosmology. In light of lacking the convincing theoretical explanation, an effective description of this phenomenon in ...terms of cosmic equation of state turns out useful. The strength of modern cosmology lies in consistency across independent, often unrelated pieces of evidence. Therefore, every alternative method of restricting cosmic equation of state is important. Strongly gravitationally lensed quasar-galaxy systems create such new opportunity by combining stellar kinematics (central velocity dispersion measurements) with lensing geometry (Einstein radius determination form position of images). In this paper we apply such method to a combined data sets from SLACS and LSD surveys of gravitational lenses. In result we obtain the cosmic equation of state parameters, which generally agree with results already known in the literature. This demonstrates that the method can be further used on larger samples obtained in the future. Independently noticed systematic deviation between fits done on standard candles and standard rulers is revealed in our findings. We also identify an important selection effect crucial to our method associated with geometric configuration of the lensing system along line of sight, which may have consequences for sample construction from the future lensing surveys.
Samples of 20 varieties of flour were examined for contents of toxic elements (Pb, Cd) and of some macro- and microelements (Mg, Zn, Cu, Fe, Mn). Chemical composition of flour and its baking ...characteristics found in the course of routine analysis were also studied. The relationship between both groups of parameters was assessed by the canonical correlation method.
Following a research program on piperazinoalkyl-substituted tricyclic purines, a number of N-9-aryl(alkyl)-piperazinopropyl substituted tetrahydropyrimido-2,1-f-purines were synthesized and tested ...pharmacologically with respect to their influence on the central nervous system. Two of the new compounds induced hypothermia and decreased the spontaneous locomotor activity of mice.
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