Multifrequency dial sensing of the atmospheric gaseous constituents using the first and second harmonics of a tunable CO2 laser radiation

The results of field measurements of concentration of some gaseous components of the atmosphere along the paths, in Sofia, Bulgaria, using a gas analyzer based on the use of a CO2 laser radiation frequency-doubled with ZnGeP2 monocrystals are presented. The gas analyzer is a traditional long path absorption meter. Radiation from the tunable CO2 laser of low pressure and from an additional He-Ne laser is directed to a colliminating hundredfold Gregori telescope with a 300 mm diameter of the principal mirror. The dimensions of the mirrors of a retroreflector 500 x 500 mm and a receiving telescope allow one to totally intercept the beam passed through the atmospheric layer under study and back

The lightest scalar glueball

Recently performed investigations of meson spectra allow us to determine the resonance structure for the waves $IJ^{PC}=00^{++}$, $10^{++}$, $02^{++}$, $12^{++}$ = $IJ^P= 1/2 0^+$ in the mass region up to 1900 MeV, thus establishing the meson multiplets $1^3P_0q\bar q$ and $2^3P_0q\bar q$. Experimental data demonstrate that there are five scalar/isoscalar states in this mass region. Four of them are $q\bar q$ states, that is, members of the $1^3P_0q\bar q$ and $2^3P_0q\bar q$ nonets, while the fifth state is an extra one not accomodated by $q \bar q$ systematics; it has the properties of the lightest scalar glueball. Analysis of the $00^{++}$-wave performed within the framework of the dispersion relation technique allows us to reconstruct the mixing of a pure gluonium with neighbouring scalar $q \bar q$ states belonging to $1^3P_0q\bar q$ and $2^3P_0q\bar q$ nonets: three scalar mesons share the gluonium state between each other -- those are two comparatively narrow resonances $f_0(1300)$ and $f_0(1500)$ and a broad resonance $f_0(1530^{+90}_{-250})$. The broad state is a descendant of the gluonium, keeping about 40-50% of its component.Comment: 48 pages, LaTeX, 25 PostScript figures, epsfig.sty. Submitted to Russian Journal Uspekhi Fiz. Nauk (Phys-Uspekhi

Air-tightness evaluation in thoracic surgery with use of laser optical-acoustic spectroscopy

The simple and effective method of the leakage test in thoracic surgery using laser photo-acoustic leak detector «LaserGasTest» was suggested and tested in experiment on mongrels. Sulfur hexafluoride used for the work of leak detector is an inert and biologically harmless gas of the 4th class of danger and its concentration in medical ventilation apparatus does not exceed 5000 mg/m3 (0.077 %). The proposed technique provides real-time high-frequency determination of location and size of leakage

Preop endovascular embolization in juvenile nasal angiofibroma management

Introduction. Juvenile nasal angiofibroma (JNA) is an aggressively expanding fibro-vascular benign tumor, which occurs in male adolescents. Surgical management of JNA is considered as one of the most difficult in rhinology, because it very often has accompanied with profuse, streaming bleeding. Endovascular embolization has successfully used for reducing the operative blood loss since 2000th. Nevertheless, there is no consensus in the literature about its expediently using because of complications, which may occur.Objective is to evaluate the effectiveness of selective angiography and endovascular embolization in reducing bleeding when removal of JNA of different stages.Materials and methods. In the N.N. Burdenko National Medical Research Center of Neurosurgery 134 patients with JNA had been treated surgically.Results. 110 patients with JNA, who underwent embolization, managed to perform total, subtotal or partial devascularization of the tumor. Total devascularization was achieved in JNA blood supply variant only from the external carotid artery (ECA) system from 1 or 2 sides  (in primary patients or in patients who had not previously been embolized) (n = 39); subtotal devascularization, if the blood supply was carried out from the ECA system, internal carotid artery (ICA) on the 1 side (n = 52) and partial, if there was blood supply from the ECA and significant from the ICA system from 2 sides (in patients with relapse after previous embolization with microspirals or the ECA ligations from 1 or 2 sides, as well as with giant JNA (n = 19). Since the vast majority of patients admitted to our clinic were previously operated on, and JNA blood supply in relapses was more pronounced, we performed the comparison of the degree of tumor devascularization depending on its blood supply in primary patients and patients with relapse. It turned out, as could be expected, that with the primary JNA often managed  to execute a total devascularization than with JNA with continued increase, the difference was statistically significant (p = 0.009).Conclusion. It accurately proved that embolization decreases intraoperative blood loss and reduce surgical risks even in later stages JNAs  (r = –0,51, p <10–7). Ligation of ECA as well as proximal occlusion of its branches leads to rapid reconstruction blood supply from ICA and inability of its embolization if recurrence of JNA occurs