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The aim of the present study was to evaluate a new improved multiplex polymerase chain reaction (PCR) hybridisation assay to detect multidrug-resistant tuberculosis. The assay, developed to detect rifampin (rpoB) and isoniazid (katG) gene mutations causing Mycobacterium tuberculosis resistance, was recently extended to include inhA gene mutations that code for low-level isoniazid resistance. Interpretable results were obtained in 115 isolates and in all smear-positive clinical specimens. Rifampin resistance was correctly identified in all specimens and in 20 of 21 (95%) multidrug-resistant isolates compared to BACTEC 460TB. Isoniazid resistance correlated in 18 of 22 (82%) specimens, in 31 of 31 (100%) high-level and 24 of 28 (86%) low-level isoniazid-resistant isolates. The assay was rapid, easy to perform and directly applicable in smear-positive specimens. We predict that the assay may be a useful tool to combat and prevent new cases of multi- and extensively drug-resistant tuberculosis.

The increasing prevalence of drug-resistant tuberculosis necessitates rapid and accurate susceptibility testing. The nonradiometric BACTEC Mycobacteria Growth Indicator Tube 960 (MGIT) system for susceptibility testing was evaluated on 222 clinical Mycobacterium tuberculosis complex isolates for isoniazid, rifampin, and ethambutol. Fifty-seven of the isolates were tested for pyrazinamide. Results were compared to those of radiometric BACTEC 460 system and discrepancies were resolved by the agar proportion method. We found an overall agreement of 99.0% for isoniazid, 99.5% for rifampin, 98.2% for ethambutol, and 100% for pyrazinamide. After resolution of discrepancies, MGIT yielded no false susceptibility for rifampin and isoniazid. Although turnaround times were comparable, MGIT provides an advantage as inoculation can be done on any weekday as the growth is monitored automatically. The automated MGIT system is a rapid and reliable alternative for susceptibility testing of M. tuberculosis complex to first-line drugs.

Propylene polymerization was investigated with the TiCl 4 /MgCl 4 supported catalyst with the stereoregulating donor pair dibutylphtalate (DBPH)/triethoxyphenylsilane (TEPS) in heptane with AlEt 3 as cocatalyst in the presence of hydrogen. It was shown that there is an activation effect by the influence of hydrogen. The removal of hydrogen from the polymerization medium results in an immediate disappearance of activation. However, the deactivation of the system is reversible, and it is possible to repeat the activation effect by hydrogen more than once. It was found that the value of the activation energy is the same in the presence of hydrogen and without it and is equal to 11 kcal/mol. From the experimental results it is concluded that the maximum number of active centres is realized in the catalytic system in the presence of hydrogen, but a value of the propagation rate constant is not changed. It was also found that in the presence of hydrogen the system's decay follows the bimolecular law of active centres deactivation.

The effect of CS 2 on the catalytic system TiCl 4 /MgCl 2 /DBPH-AlEt 3 /TEPS in propylene polymerization in the presence and absence of hydrogen was studied. It was shown that CS 2 poisons active centres in both cases by a similar way. The yield of polypropylene decreases with the CS 2 effect, but the isotactic centres poison to the greatest degree. Results obtained by the study of polymerization kinetics, fractional comosition and molecular mass distribution of polymers permit a conclusion that there is not any differentiation between initial and “hydrogen” centres, i.e. these centres have the same nature. An observed hydrogen activation effect is explained by the revival of “dormant” centres, resulting from 2-1 propylene insertion in the polymer chain in the chain transfer reaction with H 2 . Seemingly the competition between the polymerization rate retarding by irregular monomer insertion and the activation by hydrogen takes place. It leads to non-stationary kinetics of propylene polymerization in the presence of hydrogen.

The influence of some electrodeposition parameters on the structural properties of hard magnetic CoW films with perpendicular anisotropy is reported. It is shown that the character of columnar structure formation and that of the texture growth are interconnected and may be accounted for by the deposition conditions and adsorption of the products of electrode reactions at the cathode.

Atsitiktinių dydžių transformacijas, naudojančias normalų dėsnį, kone pirmieji išnagrinėjo E. A. Korniš ir R. A. Fišer [5]. Jie savo straipsnyje pasiūlė funkcijų ir formalų skleidimą eilute. Šios eilutės (tiksliau, jų dalinės sumos) yra plačiai naudojamos matematinėje statistikoje, jos vadinamos Korniš – Fišer skleidiniais. Šio darbo tikslas yra išnagrinėti, kaip Grigelionio GZD ( , , , , ) bei ( , , , ) pasiskirstymams taikomas asimptotinis Edžvorto skleidinys (daugianaris). Nagrinėjome kaip užsirašo minėtas skleidinys keičiantis parametrams. Edžvorto skleidinį išreiškėme apytiksliai. Nes naujieji semiinvariantai, gauti po to, kai centravom bei normavom Grigelionio GZD ( , , , , ) ir ( , , , ) atsitiktinį dydį, užrašyti apytiksliai. Semiinvariantų išreiškimui buvo naudojamas tik pirmas narys funkcijos , kuri užrašyta, naudojantis Eulerio – Makloreno sumavimo formule. Cornish and Fisher were the firsts scholars who have analysed transformations of the random variables are associated with normal distribution. They suggested formal expansions of the functions x(y) and y(x). These expansions are widely spread in the statistics, they are called Cornish – Fisher expansions. The research is investigated the normal approximations for other distributions. The research is investigated how Edgeworth expansions applied for Br. Grigelionis distributions GZD ( , , , , ) and ( , , , ).

A total of 196 rifampicin (RMP) resistant Mycobacterium tuberculosis isolates were searched for mutations in the cluster I region of the rpoB gene. Seventeen different types of mutations were observed in 184 (93.9%) isolates. The remaining isolates searched also had no mutations in the N-terminal region of this gene. Mutations were most frequently detected at single codons Ser531 (47.4%), His526 (20.9%), and Asp516 (20.4%). Our data indicate that genotypic drug susceptibility assays based on detection of mutations at the specific codons of the rpoB gene should be effective for predicting resistance to RMP and rifabutin and multidrug resistance in Lithuania.

Baigiamajame magistro darbe nagrinėjamos pastatų energijos vartojimo efektyvumo problemos. Ieškoma būdų, kaip galima būtų dar projektavimo arba renovacijos stadijoje sukurti energetiškai efektyvų pastatą naudojant naujoviškus metodus. Darbe atlikta literatūros, susijusios su kompiuteriniu energetiniu modeliavimu, analizė, atliktas kelių populiariausių energetinio modeliavimo programų palyginimas ir tolesniems skaičiavimams pasirinkta geriausia dinaminio modeliavimo programa – EnergyPlus. Buvo užsibrėžtas tikslas ištirti šios panaudojimo programos galimybes sprendžiant hipotetinio administracinės paskirties pastato modelį. Buvo užsibrėžti pagrindiniai uždaviniai – ištirti šio modelio šildymo/šaldymo galios priklausomybes per projektinę parą nuo įvairių faktorių. Sukūrus duomenų rinkmeną, aprašančią pastatą, buvo atliktas modeliavimas įvairiems įstiklinimo plotams, įvairioms pastato orientacijoms ir įvairioms stiklo rūšims. Buvo nustatyta atskirai šių faktorių įtaka pastato šildymo/šaldymo galiai. Tam, kad būtų galima įvertinti potencialų energijos sąnaudų sumažėjimą, kuris gali būti pasiektas taikant modeliavimą, buvo išanalizuotos dvi skirtingos to paties pastato modifikacijos: blogiausias ir geriausias variantas. Skirtumas tarp jų buvo gautas didelis, ypatingai potencialios šalčio santaupos. EnergyPlus apskaičiuota šildymo galia taip pat buvo palyginta su dviem kitomis paprastesnėmis skaičiavimo metodikomis. EnergyPlus paskaičiuota galia žymiai mažesnė, nei kitais dviem... [to full text] In this final Master paper were analyzed problems, related with buildings energy consumption and energy efficiency. For further analysis were chosen innovative tools – energy simulation programs, which help to save energy before building is built or renovated. After literature, related with building energy simulation, was analyzed, comparison of the most popular energy simulation programs was done. After this, EnergyPlus was chosen as the best dynamic energy simulation program. The main purpose of this paper – to investigate adaptability of the program in our applications. For investigation was chosen model of hypothetical office building. The main tasks were to calculate, how different factors influence building heating/cooling loads during design days. Main data file, describing building, was created and were made simulations for different cases of glazing, building orientations and glass types. After the influence of these factors was defined, for evaluating potential energy saving through energy simulation, was created the best and the worst case for the same building. Difference between cases was very big, especially in cooling loads. EnergyPlus calculation results were also compared with results of two simpler, often used heating power calculation methods. Heating power, calculated with EnergyPlus, was much smaller, than in other two cases. After all was made conclusion, that EergyPlus is adaptable in our appliances and, just through using dynamic energy simulation... [to full text]

Nations of the former Soviet Union have the world's highest reported levels of resistance to anti-tuberculosis drugs. We conducted the first national survey of anti-tuberculosis drug resistance in the Republic of Lithuania.We tested Mycobacterium tuberculosis isolates from all incident culture-positive pulmonary TB patients registered in 2002. New patients were those treated for1 month with any first-line anti-tuberculosis drug (isoniazid [INH], rifampin [RMP], ethambutol, or streptomycin); previously treated patients were those treated foror =1 month.Of 1163 isolates, 475 (41%) were resistant to at least one first-line drug, and 263 (23%) were resistant to at least INH and RMP (MDR); this included 76/818 (9.3%) from new patients and 187/345 (54%) from previously treated patients. Of 52 MDR isolates randomly selected for extended testing at an international reference laboratory, 27 (51%, 95%CI 38-66) had resistance to pyrazinamide, 21 (40%, 95%CI 27-55) to kanamycin, and 9 (17%, 95%CI 8-30) to ofloxacin.The prevalence of MDR-TB in Lithuania is among the world's highest. Among MDR-TB isolates, aminoglycoside and fluoroquinolone resistance were common. To combat drug-resistant TB, Lithuania has implemented the WHO global TB control strategy (DOTS), and is developing an MDR-TB treatment program (DOTS-Plus).

In the first attempt to establish a quality assurance programme for susceptibility testing of Mycobacterium tuberculosis to fluoroquinolones, 20 strains with different fluoroquinolone susceptibility patterns were distributed by the Supranational Reference Laboratory in Stockholm to the other mycobacterial reference laboratories of the Nordic and Baltic countries. Susceptibility testing to fluoroquinolones was performed according to routine procedures in each laboratory. Results were compared to sequence analysis of the gyrA gene and minimal inhibitory concentration determination. Most laboratories found identical susceptibility patterns. The two resistant strains were correctly identified by all laboratories, but three laboratories each falsely reported one susceptible strain as resistant. These results indicate that the participating laboratories yield reliable results in detection of fluoroquinolone-resistant strains, although the need for a standardised quality assurance programme for drug susceptibility testing for fluoroquinolones is stressed by the strains falsely reported as resistant.

Exchange reactions between alkyl groups in the presence of AlEt2Cl, AlEtCl2, or AlCl3 were studied in homogeneous systems based on Cp2TiCl2. Alkylation of Cp2TiCl2 and dealkylation of Cp2TiEtCl are preceded by the formation of adducts of the Ti complexes with an Al-compound. A change in temperature from −20 to +20°C alters the stability constants of these adducts only slightly. Alkylation proceeds via two parallel, intramolecular and bimolecular, mechanisms. The high negative activation entropy of the unimolecular reaction (ΔS†) = −30 e.u.) points to the appearance of a cyclic transition state. The addition of water and oxygen does not change appreciably the rate of the intramolecular TiC reaction. The addition of ethylene substantially decelerates dealkylation of Cp2TiEtCl without affecting the alkylation reaction.