508 research outputs found
Mapping Global Star Formation in the Interacting Galaxy Pair Arp32
A multi-wavelength set of photometric data including UV (GALEX), optical, near-IR, infrared (Spitzer) and radio (VLA 20cm) images and spectroscopic observations are used to map the dust-obscured and unobscured star formation in the galaxy pair Arp 32. The system consists of an actively starforming galaxy and another one with depressed star formation. The most active galaxy has disrupted morphology and different sites of star formation. Spectroscopic data show hints of nuclear activity in its core, intense star formation in limited regions of the galaxy as well as an underlying population of stars witnessing a past episode of star formation. Current star formation rates are estimated from UV and bolometric IR luminosities
Connecting Clump Sizes in Turbulent Disk Galaxies to Instability Theory
In this letter we study the mean sizes of Halpha clumps in turbulent disk
galaxies relative to kinematics, gas fractions, and Toomre Q. We use 100~pc
resolution HST images, IFU kinematics, and gas fractions of a sample of rare,
nearby turbulent disks with properties closely matched to z~1.5-2 main-sequence
galaxies (the DYNAMO sample). We find linear correlations of normalized mean
clump sizes with both the gas fraction and the velocity dispersion-to-rotation
velocity ratio of the host galaxy. We show that these correlations are
consistent with predictions derived from a model of instabilities in a
self-gravitating disk (the so-called "violent disk instability model"). We also
observe, using a two-fluid model for Q, a correlation between the size of
clumps and self-gravity driven unstable regions. These results are most
consistent with the hypothesis that massive star forming clumps in turbulent
disks are the result of instabilities in self-gravitating gas-rich disks, and
therefore provide a direct connection between resolved clump sizes and this in
situ mechanism.Comment: Accepted to Apj Letter
Effects of three types of physical activity on reduction of metabolic parameters involved in cardiovascular risk
The aim of present study was to investigate the effects of three different types of physical activity on reduction of the metabolic parameters mainly responsible for cardiovascular diseases. This prospective-intervention study was performed at the 'ÄIGOTA' Thyroid Institute on Mt. Zlatibor (Serbia) between August 2004 and June 2006. Sixty-eight overweight/obese patients aged 40-70 years with hyperlipidemia were divided into three groups according to their weight and overall health. The program of physical workout included: group I - fast walking; group II - gymnastic exercises and specially chosen exercises in the swimming pool; and group III - combined physical training of higher intensity and greater length. All patients were also on a special reduced diet of 1000 kcal per day, the AHA step-2 diet. We monitored the body mass index, body composition, glucose, cholesterol (total, LDL-, and HDL-), and triglycerides before, during, and after the intervention. After 2 and particularly 12 weeks of intervention, a significant improvement of all metabolic parameters was achieved in all three groups of patients. Although most patients completed the study with normal values of all parameters, the most desirable results were achieved in group III (combined exercises with an average energy expenditure of 900 kcal per day). Our research indicates that a specially conceived program of physical activity and diet intervention resulted in significant reduction of cardiovascular risk factors
Extragalactic Fields Optimized for Adaptive Optics
In this paper we present the coordinates of 67 55' x 55' patches of sky which
have the rare combination of both high stellar surface density (>0.5
arcmin^{-2} with 13<R<16.5 mag) and low extinction (E(B-V)<0.1). These fields
are ideal for adaptive-optics based follow-up of extragalactic targets. One
region of sky, situated near Baade's Window, contains most of the patches we
have identified. Our optimal field, centered at RA: 7h24m3s, Dec: -1deg27'15",
has an additional advantage of being accessible from both hemispheres. We
propose a figure of merit for quantifying real-world adaptive optics
performance, and use this to analyze the performance of multi-conjugate
adaptive optics in these fields. We also compare our results to those that
would be obtained in existing deep fields. In some cases adaptive optics
observations undertaken in the fields given in this paper would be orders of
magnitude more efficient than equivalent observations undertaken in existing
deep fields.Comment: 28 pages, 15 figures, 1 table; accepted for publication in PAS
Educational recommendations for the conduct, content and format of EULAR musculoskeletal ultrasound Teaching the Teachers Courses
To produce educational guidelines for the conduct, content and format of theoretical and practical teaching at EULAR musculoskeletal ultrasound (MSUS) Teaching the Teachers (TTT) Courses
FiziÄka aktivnost u prevenciji i redukciji kardiovaskularnog rizika
Introduction There is evidence that physical activity decreases the degree of atherosclerosis in the coronary arteries in persons who are physically active by modifying the chemistry and metabolism of lipoproteins. The effect of physical activity on the lipid status is achieved by affecting the enzymes of lipoprotein metabolism including the lipoprotein and liver lipase and transport protein of cholesterol esters. Epidemiological investigations on the effect of physical activity in prevention of cardiovascular diseases point to the fact that the persons who have a higher degree of cardio-respiratory endurance have a much lower mortality rate than those with a lower degree. The positive effect of physical activity on the cardiovascular system is reflected on the improved aerobic capacity, metabolic function, amplification of lipid profile, insulin sensitivity, immunological functions; it increases the perfusion of myocardium and the fibrinolytic activity, and reduces the adherence of thrombocytes due to increased synthesis of prostaglandin (PGI2), it also enhances the energy consumption, which is important in the maintenance of ideal bodyweight, prevention and treatment of obesity, and it has a positive effect on the control of stress. Conclusion With respect to the effects on the lipid status, aerobic physical exercises like running, swimming, cycling, with the intensity of training of a medium (65% VO2) load, have a positive effect on lipid status. The best form of physical activity is the one in which the endurance and power are increased.Pozitivan efekat fiziÄke aktivnosti na kardiovaskularni sistem ogleda se u: poboljÅ”anju aerobnog kapaciteta i metaboliÄkih funkcija, amplifikaciji lipidnog profila, insulinske senzitivnosti imunoloÅ”kih funkcija, poveÄanju perfuzije miokarda i fibrinolitiÄke aktivnosti, smanjenju adherentnosti trombocita zbog poveÄane sinteze prostanglandina PGI2, porastu energetskog rashoda (Å”to je znaÄajno za održavanje idealne telesne mase), prevenciji i leÄenju gojaznosti, kao i kontroli stresa. EpidemioloÅ”ke studije ukazuju na pozitivnu vezu poveÄane energetske potroÅ”nje uzrokovane fiziÄkom aktivnoÅ”Äu i redukcije lipidnih parametara i telesne mase kombinacijom dijete i fiziÄke aktivnosti. FiziÄka aktivnost, modifikujuÄi hemizam i metabolizam lipoproteina, usporava stepen ateroskleroze u koronarnim arterijama kod osoba koje su fiziÄki aktivne. U prevenciji i redukciji kardiovaskularnog rizika aerobne fiziÄke vežbe (poput trÄanja, plivanja, vožnje bicikla), sa intenzitetom treninga srednjeg optereÄenja (65% srednjeg respiratornog volumena) optereÄenja, imaju pozitivan efekat. Najbolji oblik fiziÄke aktivnosti je onaj u kojem se poveÄavaju izdržljivost i snaga
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