Single-longitudinal-mode pumped pulsed-dye amplifier for high-resolution laser spectroscopy.

The In-Gas-jet Laser Ionization and Spectroscopy (IGLIS) technique relies on narrow-bandwidth, high-peak-power, short-pulse-length (≈10 ns), and high-repetition-rate laser pulses to probe, precisely and efficiently, the hyperfine structure of medium-heavy and heavy isotopes, embedded in a supersonic jet. The power and repetition rate requirements of the laser system are met by combining ≈100 W, 8 ns pulse width, 10 kHz commercial Nd:YAG pump lasers with a single-mode continuous wave seeded Pulsed Dye Amplifier (PDA). The common multi-longitudinal-mode operation of these Nd:YAG pump lasers causes, however, undesirable frequency sidebands in the output spectrum of the PDA system, hindering the attainable spectral resolution, a correct interpretation, and an accurate analysis of the hyperfine spectra. In this article, a new prototype Nd:YAG laser is presented, which combined with the PDA system is capable of providing quasi-transform-limited laser pulses at 10 kHz, with only limited losses in laser power. This system reduces any spectral sideband amplitude below a proven upper limit of 0.2% with one order of magnitude extra reduction expected based on simulations. A full characterization of both the Nd:YAG and PDA laser systems is done by studying the temporal and frequency behavior in detail. This study is finalized by a performance benchmark of this combined laser system in the hyperfine spectroscopy of copper isotopes, showcasing its applicability for future IGLIS studies.

[Prevention of complications in patients with cleft lip and palate combined with teeth crowding receiving long-term orthodontic treatment]. / Profilaktika razvitiya oslozhnenii pri dlitel'nom ortodonticheskom lechenii patsientov s rasshchelinoi neba i guby, sochetayushcheisya so skuchennym polozheniem zubov.

This study aim was to improve the effectiveness of treatment of patients with cleft lip and palate in combination with crowding of teeth receiving long-term orthodontic treatment. The study involved 30 patients divided in 3 groups in which chlorhexidine-containing medication was included in the individual prevention and treatment program. The effectiveness of using 0.2% CG gel was assessed after 6 months to control the development of inflammatory phenomena in periodontal tissues during long-term orthodontic treatment. The obtained clinical and laboratory data indicate the normalization of the cytokine profile and oral hygiene indices as a result of using a CG-containing preparation for effective control of the biofilm etiological factor.

Towards high-resolution laser ionization spectroscopy of the heaviest elements in supersonic gas jet expansion.

Resonant laser ionization and spectroscopy are widely used techniques at radioactive ion beam facilities to produce pure beams of exotic nuclei and measure the shape, size, spin and electromagnetic multipole moments of these nuclei. However, in such measurements it is difficult to combine a high efficiency with a high spectral resolution. Here we demonstrate the on-line application of atomic laser ionization spectroscopy in a supersonic gas jet, a technique suited for high-precision studies of the ground- and isomeric-state properties of nuclei located at the extremes of stability. The technique is characterized in a measurement on actinium isotopes around the N=126 neutron shell closure. A significant improvement in the spectral resolution by more than one order of magnitude is achieved in these experiments without loss in efficiency.

Two-step laser ionization schemes for in-gas laser ionization and spectroscopy of radioactive isotopes.

The in-gas laser ionization and spectroscopy technique has been developed at the Leuven isotope separator on-line facility for the production and in-source laser spectroscopy studies of short-lived radioactive isotopes. In this article, results from a study to identify efficient optical schemes for the two-step resonance laser ionization of 18 elements are presented.

Early onset of ground state deformation in neutron deficient polonium isotopes.

In-source resonant ionization laser spectroscopy of the even-A polonium isotopes (192-210,216,218)Po has been performed using the 6p(3)7s (5)S(2) to 6p(3)7p (5)P(2) (λ=843.38 nm) transition in the polonium atom (Po-I) at the CERN ISOLDE facility. The comparison of the measured isotope shifts in (200-210)Po with a previous data set allows us to test for the first time recent large-scale atomic calculations that are essential to extract the changes in the mean-square charge radius of the atomic nucleus. When going to lighter masses, a surprisingly large and early departure from sphericity is observed, which is only partly reproduced by beyond mean field calculations.

Magnetic dipole moment of (57,59)Cu measured by in-gas-cell laser spectroscopy.

For the first time, in-gas-cell laser spectroscopy study of the (57,59,63,65)Cu isotopes has been performed using the 244.164 nm optical transition from the atomic ground state of copper. The nuclear magnetic dipole moments for (57,59,65)Cu relative to that of (63)Cu have been extracted. The new value for (57)Cu of mu((57)Cu) = +2.582(7)mu(N) is in strong disagreement with the previous literature value but in good agreement with recent theoretical and systematic predictions.

Heterogeneity of morphological and functional changes in various compartments of rat urinary bladder in infravesical obstruction of the urinary tract.

Infravesical obstruction of the lower urinary tract was simulated in rats by dosed constriction of the prevesical portion of the urethra. The functional and morphological changes in various urinary bladder compartments were evaluated after 1 week and 3 months. The development of compensatory hypertrophy of the detrusor was associated with an increase in the number of hypertrophic, atrophic, and young leiomyocyte forms and their transformation into myofibroblasts, with the formation of connective tissue laminae between myofibril bundles mainly in the zone of urinary urinary bladder neck. Specific contractility of the detrusor strips decreased with increasing their tone, which was most pronounced in the neck zone. The relaxing effect of norepinephrine was significantly lower after 3 months of obstruction and virtually disappeared in the zone of the urinary bladder body and neck. Blockade of a-adrenoceptors after adrenostimulation with norepinephrine stimulated contractions of the hypertrophic detrusor against the background of reduced tone of the urinary bladder neck, in contrast to intact urinary bladder where this treatment reduced contractions.

Morphological changes in the kidneys of rats with postischemic acute renal failure after intrarenal administration of fetal mesenchymal stem cells from human bone marrow.

Chronic experiments on outbred albino rats were performed to compare the dynamics of histological signs for postischemic renal injury (90-min thermal ischemia) after intraparenchymal injection of cultured fetal MSC from human bone marrow. Functional indexes of the ischemic kidney were predetermined. In the early period after ischemia (day 4), administration of human bone marrow MSC was followed by the increase in blood flow in the microcirculatory bed and decrease in the degree of alteration in renal tubules. An increase in the area of zones with histological signs for normal function of tubules was accompanied by the improvement of biochemical indexes for renal function. In the delayed period, a protective effect of cell therapy was manifested in the prevention of death of renal tubules. Mild calcification of the necrotic tubular epithelium served as a marker of this process. Human bone marrow MSC were labeled with the fluorescent probe Calcein. These cells migrated from the site of injection, spread in the interstitium, and retained viability for 7 days. During this period, some cells were incorporated into the lumen of renal tubules.