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The HIV epidemic in Eastern Europe and Russia is large and not well-controlled. To describe the more recent molecular epidemiology of HIV-1, transmitted drug resistance, and the relationship between the epidemics in this region, we sequenced the protease and reverse transcriptase genes of HIV-1 from 812 people living with HIV from Ukraine (n = 191), Georgia (n = 201), and Russia (n = 420) before the initiation of antiretroviral therapy. In 190 Ukrainian patients, the integrase gene sequence was also determined. The most reported route of transmission was heterosexual contact, followed by intravenous drug use, and men having sex with men (MSM). Several pre-existing drug resistance mutations were found against non-nucleoside reverse transcriptase inhibitors (RTIs) (n = 103), protease inhibitors (n = 11), and nucleoside analogue RTIs (n = 12), mostly polymorphic mutations or revertants. In the integrase gene, four strains with accessory integrase strand transfer inhibitor mutations were identified. Sub-subtype A6 caused most of the infections (713/812; 87.8%) in all three countries, including in MSM. In contrast to earlier studies, no clear clusters related to the route of transmission were identified, indicating that, within the region, the exchange of viruses among the different risk groups may occur more often than earlier reported.

This study analyzes the HIV-1 subtype diversity and its phylodynamics in Moscow region, which is the most densely populated area of Russia characterized by high rates of internal and external migration. The demographic and viral data from 896 HIV-infected individuals collected during 2011–2016 were analyzed. The study revealed broad diversity in the HIV-1 subtypes found in Moscow, which included A6 (85.1%), B (7.6%), CRF02_AG (1.2%) and URF_A6/B recombinants (4.2%). Other HIV-1 subtypes were detected as single cases. While A6 was most prevalent (>86.0%) among heterosexuals, injecting drug users and cases of mother-to-child transmission of HIV, subtype B (76.3%) was more common in men who have sex with men. Phylogenetic reconstruction revealed that the A6 sequences were introduced into the epidemic cluster that arose approximately around 1998. Within the subtype B, six major epidemic clusters were identified, each of which contained strains associated with only one or two dominant transmission routes. The date of origin of these clusters varied between 1980 and 1993, indicating that the HIV-1 B epidemic began much earlier than the HIV-1 A6 epidemic. Reconstruction of the demographic history of subtypes A6 and B identified at least two epidemic growth phases, which included an initial phase of exponential growth followed by a decline in the mid/late 2010s. Thus, our results indicate an increase in HIV-1 genetic diversity in Moscow region. They also help in understanding the HIV-1 temporal dynamics as well as the genetic relationships between its circulating strains.

The men who have sex with men (MSM) population infected with HIV is poorly studied in Russia because of stigma and discrimination. In the first years of the HIV epidemic, the only HIV genetic variant that circulated among MSM was subtype B, usually acquired abroad. Meanwhile, the massive epidemic of HIV in Russia was caused by a highly homogenic subtype A variant, AFSU (A6), and spread mainly among drug users. In this study, 155 HIV pol sequences from MSM collected during the 2006-2016 period were analyzed. Phylogenetic analysis found that 19.4% of the viral sequences from MSM clustered with HIV genetic variants A6 and BFSU, which were previously identified only among drug users and their heterosexual partners. These data show that the MSM population in Russia is gradually becoming less isolated from the general epidemic process. Urgent measures should be taken to prevent the spread of HIV among the MSM population.

A new technique to measure the toughness of metal—ceramic interfaces is presented. In this technique, a test coating of 100 to 200 A is deposited on the substrate of interest. This layer is then overlaid by a residually stressed Nb coating (used as a loading device), and its thickness is controlled until the lower test layer buckles away from the substrate. By determining the intrinsic residual strain within the Nb layer in independent delamination experiments, the bilayer buckling morphology is quantified, and a measure of the interface fracture toughness is obtained. This technique has been successfully applied to interfaces between metallic coatings of Sb, Cr, Cu, Nb, Al, and substrates of sapphire with (0001) orientation. Interface toughness values of 0.31, 0.94, 0.93, 0.88, and 1.0 J/m2 were obtained for these systems, respectively.

This paper summarizes recent developments in the laser spallation technique for measuring the tensile strength of planar thin film interfaces. In this technique, a laser-produced compressive stress pulse in the substrate, reflecting from the coating's free surface, pulls the interface in tension and leads to its failure if the tensile amplitude is high enough. Earlier, the critical stress amplitude that accomplishes the removal of the coating was determined through a computer simulation of the process. Recently, the technique was modified so that the interface stress can be determined directly by recording the coating or substrate free-surface velocities using a Doppler interferometer. The recorded surface velocity is related to the interface stress via an elastic wave mechanics simulation. Interface strengths of several metal/ceramic, ceramic/ceramic and ceramic/polymer systems are summarized from our recent efforts. In addition, two developments, the first a novel interferometer to record velocities fro...

An interferometer is presented which is capable of measuring the free‐surface velocities and displacements of both specular and diffuse surfaces. The setup utilizes a previously used principle of producing a virtual image of one mirror at the same distance from the photodiode as the second mirror of the interferometer, albeit with considerable simplification. It is shown that use of a He–Ne laser of only 5‐mW power can produce high contrast displacement fringes from surfaces of materials with nonuniform microstructure, including composites. Substrates of carbon–carbon composites and polycrystalline alumina with nonuniform microstructure on the scale of 5–10 μm, and with peak velocities up to 150 m/s were considered. An experimental strategy which allows one to covert the optical setup to either a velocity or a displacement interferometer is also discussed. It is further shown that use of a fast photodiode and a high‐speed digitizer with a 5‐ps rise time provides a time resolution of 0.2 ns for recording the displacement fringes, and allows measuring free surface velocities up to 800 m/s. This is demonstrated by measuring such transient surface velocities with rise times of 1 ns on a specular Si surface. In all the experiments reported here, the surface velocities were produced by the reflection of a stress wave, which in turn was generated on the back surface of the substrate, using a Nd:YAG laser pulse.

Stress pulses with rise times of 1.14 ns and amplitudes in excess of 3 GPa are produced using an Nd:YAG laser. In contrast to pulse profile assuming an asymptotic tail at about 5% to 10% of the peak stress, the pulses reported here show much sharper, post‐peak decays resulting in a zero stress at about 17 ns. Use of such stress pulses in the determination of the tensile strength of planar interfaces between thin coatings of 0.1‐μm thickness and substrates is also discussed.

Background In HIV discordant couples (one parther is HIV-infected, another is HIV-uninfected) HIV-negative partners often remain uninfected for a long time despite long, stable, often unprotected sexual contacts with HIV-infected partner. The increase of time of living together accompanying the decrease of the incidence of HIV infection in HIV-negative partner. The features of HIV-specific immune response in HIV discorgant couples was investigated. Methods Thirty-three HIV discordant couples from Moscow region living together

This bibliography is oriented toward guerrillas and guerrilla warfare as a weapon system used by the Soviet Army in fighting the Germans. While it relates basically to the tactics and techniques of Soviet guerrilla fighting during World War II, it was an element of a larger study designed to explore internal (revolutionary) was as an instrument and process of socio-political change.