232 research outputs found

    Accessing methadone within Moldovan prisons: Prejudice and myths amplified by peers.

    Get PDF
    BACKGROUND: The volatile HIV epidemic in Moldova, driven primarily by people who inject drugs (PWIDs), is concentrated in prisons. Although internationally recommended opioid agonist therapy (OAT) is available in Moldovan prisons, coverage remains inadequate and expansion efforts have failed to meet national and international goals. METHODS: To better understand why eligible prisoners are reluctant to initiate OAT, we surveyed recently released prisoners who met criteria for opioid dependence and compared those who had and had not been enrolled in within-prison OAT (N=56) using standardized scales on OAT knowledge and attitudes as well as within-prison harassment experiences. RESULTS: Knowledge about OAT was similar between both groups, but this knowledge and myths about OAT had independent and opposite direct effects on OAT attitudes. Those who were enrolled in OAT in prison were significantly more likely to perceive it as an effective form of treatment and had more tolerable attitudes toward OAT but were also more likely to have been bullied and to express concerns about their personal safety. Prisoners who had not been enrolled in OAT were more likely to endorse negative myths about methadone; only one person among them intended to receive OAT in the future. CONCLUSION: In Moldovan prisons, OAT enrollment and treatment continuation are influenced by ideological biases and myths that are largely formed, amplified, and reinforced behaviorally in restricted prison settings. Future interventions that expand OAT in prisons should target individual-level ideological prejudices and myths, as well as the prison environment.<br/

    Loffe-Regel' crossover and boson peaks in disordered solid solutions and similar anomalies in heterogeneous crystalline structures

    Get PDF
    Low-frequency features of the phonon spectra of disordered solid solutions and heterogeneous crystalline structures are analyzed at the microscopic level. It is shown that boson-peak type excitations can arise in disordered solid solutions whose sites have only translational degrees of freedom. Thus it is established that such excitations appear mainly because of the additional positional dispersion of sound waves which is due to the disordering. The influence of boson-peak excitations on the low-temperature specific heat is investigated. It is found that in a number of cases the specific heat is more sensitive to excitations of this kind than the low-frequency density of states is. It is shown that anomalies similar to Ioffe-Regel' crossover and boson peaks can also arise in disordered heterogeneous crystalline structures with a complicated lattice

    The GRA Beam-Splitter Experiments and Particle-Wave Duality of Light

    Full text link
    Grangier, Roger and Aspect (GRA) performed a beam-splitter experiment to demonstrate the particle behaviour of light and a Mach-Zehnder interferometer experiment to demonstrate the wave behaviour of light. The distinguishing feature of these experiments is the use of a gating system to produce near ideal single photon states. With the demonstration of both wave and particle behaviour (in two mutually exclusive experiments) they claim to have demonstrated the dual particle-wave behaviour of light and hence to have confirmed Bohr's principle of complementarity. The demonstration of the wave behaviour of light is not in dispute. But we want to demonstrate, contrary to the claims of GRA, that their beam-splitter experiment does not conclusively confirm the particle behaviour of light, and hence does not confirm particle-wave duality, nor, more generally, does it confirm complementarity. Our demonstration consists of providing a detailed model based on the Causal Interpretation of Quantum Fields (CIEM), which does not involve the particle concept, of GRA's which-path experiment. We will also give a brief outline of a CIEM model for the second, interference, GRA experiment.Comment: 24 pages, 4 figure

    New quaternary ammonium pyridoxine derivatives: synthesis and antibacterial activity

    Get PDF
    © 2017, Springer Science+Business Media, LLC. A diverse library of 34 new quaternary mono-ammonium and bis-ammonium pyridoxine derivatives was synthesized, and their antibacterial activity against several clinically relevant bacterial strains was evaluated in vitro. Several mono-ammonium compounds demonstrated high antibacterial activity against methicillin-resistant Staphylococcus strains with minimum inhibitory concentrations in the range of 0.5–8 µg/mL, which exceeded activity of miramistin and was comparable to that of benzalkonium chloride. SOS-chromotest in Salmonella typhimurium showed the lack of DNA-damage activity for all active compounds. A clear correlation has been observed between the lipophilicity of the obtained compounds and their activity against the studied Gram-positive bacterial strains. Cytotoxicity studies on HEK-293 cells demonstrated that some of the active compounds were less toxic than the reference drugs. Antibacterial activity studies in the presence of CaCl 2 suggested that the cell wall damage associated with the removal of Ca 2+ ions from the bacterial membrane is one of the possible mechanisms of antibacterial activity. The obtained results make the described active compounds a promising starting point for the development of new antibacterial therapies

    Synthesis, antibacterial and antitumor activity of methylpyridinium salts of pyridoxine functionalized 2-amino-6-sulfanylpyridine-3,5-dicarbonitriles

    Get PDF
    © 2018, © 2018 Taylor & Francis. A library of 29 2-amino-6-sulfanylpyridine-3,5-dicarbonitriles functionalized with a pyridoxine moiety was synthesized using a three-component one-pot reaction of aldehyde derivative of pyridoxine, malononitrile, and thiophenol. The obtained bipyridine structures were converted into methylpyridinium salts. Several compounds demonstrated expressed antibacterial activity with MICs (minimum inhibitory concentrations) in the range of 0.5–4 µg/mL against the three studied Gram-positive strains and 8–64 µg/mL against the Gram-negative E. coli strain, which was comparable or better than the activity of the reference antimicrobial agents. At the same time, all the synthesized compounds were inactive against the Gram-negative P. aeruginosa. Several compounds also demonstrated high cytotoxic activity against the studied tumor cells, but without selectivity for the normal HSF (human foreskin fibroblast) cells. Despite the preliminary character of the performed biological studies, the obtained results make the obtained structural chemotype a promising starting point for the design of physiologically active compounds

    Methods and Means of Determination Dynamic Strength of Water

    Get PDF
    В настоящей работе представлены результаты исследований с целью определения кавитационной прочности воды. Предложено использовать изменение зависимости скорости сдвига от сдвигающих напряжений в качестве критерия, позволяющего определить момент перехода от сплошного потока к кавитационному. Для обработки экспериментальных результатов проведены численные расчеты с использованием метода локальной полиномиальной регрессии. Обработка данных методами аппроксимации позволила продемонстрировать, что коэффициент динамической вязкости воды, в области однофазного течения являющийся константой при постоянной температуре, снижается при начале нарушения сплошности потока, т.е. кавитационных процессах в жидкостиThis paper presents the results of studies to determine the cavitation strength of water. It is proposed to use the change in the dependence of the shear rate on shear stresses as a criterion for determining the moment of transition from a continuous flow to a cavitation one. To process the experimental results, numerical calculations were carried out using the method of local polynomial regression. Data processing by approximation methods made it possible to demonstrate that the coefficient of dynamic viscosity of water, which is a constant at a constant temperature in the region of a single-phase flow, decreases at the onset of flow discontinuity, i.e., cavitation processes in the liqui

    High-Resolution 3D Structure Determination of Kaliotoxin by Solid-State NMR Spectroscopy

    Get PDF
    High-resolution solid-state NMR spectroscopy can provide structural information of proteins that cannot be studied by X-ray crystallography or solution NMR spectroscopy. Here we demonstrate that it is possible to determine a protein structure by solid-state NMR to a resolution comparable to that by solution NMR. Using an iterative assignment and structure calculation protocol, a large number of distance restraints was extracted from 1H/1H mixing experiments recorded on a single uniformly labeled sample under magic angle spinning conditions. The calculated structure has a coordinate precision of 0.6 Å and 1.3 Å for the backbone and side chain heavy atoms, respectively, and deviates from the structure observed in solution. The approach is expected to be applicable to larger systems enabling the determination of high-resolution structures of amyloid or membrane proteins
    corecore