Influence of loudspeaker directivity on the measurement uncertainty of the acoustic testing of facades.

One of the most significant aspects of a building?s acoustic behavior is the airborne sound insulation of the room façades, since this determines the protection of its inhabitants against environmental noise. For this reason, authorities in most countries have established in their acoustic regulations for buildings the minimum value of sound insulation that must be respected for façades. In order to verify compliance with legal requirements it is usual to perform acoustic measurements in the finished buildings and then compare the measurement results with the established limits. Since there is always a certain measurement uncertainty, this uncertainty must be calculated and taken into account in order to ensure compliance with specifications. The most commonly used method for measuring sound insulation on façades is the so-called Global Loudspeaker Method, specified in ISO 140-5:1998. This method uses a loudspeaker placed outside the building as a sound source. The loudspeaker directivity has a significant influence on the measurement results, and these results may change noticeably by choosing different loudspeakers, even though they all fulfill the directivity requirements of ISO 140-5. This work analyzes the influence of the loudspeaker directivity on the results of façade sound insulation measurement, and determines its contribution to measurement uncertainty. The theoretical analysis is experimentally validated by means of an intermediate precision test according to ISO 5725-3:1994, which compares the values of sound insulation obtained for a façade using various loudspeakers with different directivities. Keywords: Uncertainty, Façade, Insulatio

Comparative characteristics of future theater art specialists’ professional training in Ukraine and the USA

The article provides a comparative analysis of the training of future theater professionals at universities in Ukraine and the United States. The author reviews modern scientific works on the problem of professional training in general and optimal approaches to the selection of criteria for comparative research. On the basis of a comparative comparison, common and different aspects of professional training of future theater professionals at universities in Ukraine and the United States were clarified. The author determined that the peculiarities of the methodological principles are that in the United States they are presented more widely and more thoroughly in legislative documents; the concept of professional training of future specialists in theater art, approaches and principles in general determine the vector of further development of the system of professional training in the research area; standards in the United States are also comprehensive and specific, which provides better control over the quality of higher education in the theater; qualification requirements in the United States and Ukraine largely coincide (qualifications, features of vocational education - terms and institutions where it is possible to get a profession); content structure and list of disciplines is characterized by flexibility, diversity and differentiation in the US, which provides a wider range of individual trajectory of vocational education, while in Ukraine the list of disciplines and their content is much narrower); forms, methods and tools that are also component components of organizational and methodological principles in the system of university education in the United States and Ukraine are characterized by variability and generally provide quality training for future theater professionals in both countrie

Modulation of the virus-receptor interaction by mutations in the V5 loop of feline immunodeficiency virus (FIV) following in vivo escape from neutralising antibody

<b>BACKGROUND:</b> In the acute phase of infection with feline immunodeficiency virus (FIV), the virus targets activated CD4+ T cells by utilising CD134 (OX40) as a primary attachment receptor and CXCR4 as a co-receptor. The nature of the virus-receptor interaction varies between isolates; strains such as GL8 and CPGammer recognise a "complex" determinant on CD134 formed by cysteine-rich domains (CRDs) 1 and 2 of the molecule while strains such as PPR and B2542 require a more "simple" determinant comprising CRD1 only for infection. These differences in receptor recognition manifest as variations in sensitivity to receptor antagonists. In this study, we ask whether the nature of the virus-receptor interaction evolves in vivo.<p></p> <b>RESULTS:</b> Following infection with a homogeneous viral population derived from a pathogenic molecular clone, a quasispecies emerged comprising variants with distinct sensitivities to neutralising antibody and displaying evidence of conversion from a "complex" to a "simple" interaction with CD134. Escape from neutralising antibody was mediated primarily by length and sequence polymorphisms in the V5 region of Env, and these alterations in V5 modulated the virus-receptor interaction as indicated by altered sensitivities to antagonism by both anti-CD134 antibody and soluble CD134.<p></p> <b>CONCLUSIONS:</b> The FIV-receptor interaction evolves under the selective pressure of the host humoral immune response, and the V5 loop contributes to the virus-receptor interaction. Our data are consistent with a model whereby viruses with distinct biological properties are present in early versus late infection and with a shift from a "complex" to a "simple" interaction with CD134 with time post-infection.<p></p&gt

The DC-SIGN-CD56 interaction inhibits the anti-dendritic cell cytotoxicity of CD56 expressing cells

BACKGROUND: This study aimed to clarify interactions of the pattern-recognition receptor DC-SIGN with cells from the HIV-infected peripheral blood lymphocyte cultures. METHODS: Cells from control and HIV-infected peripheral blood lymphocyte cultures were tested for the surface expression of DC-SIGN ligands. The DC-SIGN ligand expressing cells were analyzed for the role of DC-SIGN-ligand interaction in their functionality. RESULTS: In the vast majority of experiments HIV-infected lymphocytes did not express detectable DC-SIGN ligands on their cell surfaces. In contrast, non-infected cells, carrying NK-specific marker CD56, expressed cell surface DC-SIGN ligands. The weakly polysialylated CD56 was identified as a novel DC-SIGN ligand. The treatment of DC-SIGN expressing dendritic cells with anti-DC-SIGN antibodies increased the anti-dendritic cell cytotoxicity of CD56(pos) cells. The treatment of CD56(pos) cells with a peptide, blocking the weakly polysialylated CD56-specifc trans-homophilic interactions, inhibited their anti-dendritic cells cytotoxicity. CONCLUSIONS: The interaction between DC-SIGN and CD56 inhibits homotypic intercellular interactions of CD56(pos) cells and protects DC-SIGN expressing dendritic cells against CD56(pos) cell-mediated cytotoxicity. This finding can have an impact on the development of approaches to HIV infection and cancer therapy as well as in transplantation medicine

Extraction and Serological Properties of Mycobacterium Cell Surface and Excreted Proteins

© 2017, Springer Science+Business Media, LLC, part of Springer Nature. Modern medicine still faces the task of distinguishing active and latent tuberculosis cases at the early stage of the disease. Serological approaches have their advantages for their use in diagnostics. However, the progress of these approaches is ongoing but further progress is needed to meet the needs for this disease. Here, we extracted Mycobacterium tuberculosis H37Rv proteins from culture medium or from the cell surface and studied their reactivity with anti-M. tuberculosis serum in both ELISA and immunoblots. We found that M. tuberculosis surface proteins, extracted using dimethyl sulfoxide, with molecular weights in the range of 6.5–200 kDa, showed strong specific reactivity with anti-M. tuberculosis positive serum. While excreted proteins in the molecular weight range of 32–45 kDa had the highest reactivity. The latter was confirmed serologically when very weak signal was detected from the filtrate fractions compared to stronger activity from the Vivaspin 50 kDa MWCO retentates. Moreover, Mycobacterium bovis and tuberculosis proteins from the filter retentates had clear specific serum reactivity, which suggests that this approach can be used for differential diagnosis of two infections

The carbohydrate at asparagine 386 on HIV-1 gp120 is not essential for protein folding and function but is involved in immune evasion

<p>Abstract</p> <p>Background</p> <p>The HIV-1 envelope glycoprotein gp120, which mediates viral attachment to target cells, consists for ~50% of sugar, but the role of the individual sugar chains in various aspects of gp120 folding and function is poorly understood. Here we studied the role of the carbohydrate at position 386. We identified a virus variant that had lost the 386 glycan in an evolution study of a mutant virus lacking the disulfide bond at the base of the V4 domain.</p> <p>Results</p> <p>The 386 carbohydrate was not essential for folding of <it>wt </it>gp120. However, its removal improved folding of a gp120 variant lacking the 385–418 disulfide bond, suggesting that it plays an auxiliary role in protein folding in the presence of this disulfide bond. The 386 carbohydrate was not critical for gp120 binding to dendritic cells (DC) and DC-mediated HIV-1 transmission to T cells. In accordance with previous reports, we found that N386 was involved in binding of the mannose-dependent neutralizing antibody 2G12. Interestingly, in the presence of specific substitutions elsewhere in gp120, removal of N386 did not result in abrogation of 2G12 binding, implying that the contribution of N386 is context dependent. Neutralization by soluble CD4 and the neutralizing CD4 binding site (CD4BS) antibody b12 was significantly enhanced in the absence of the 386 sugar, indicating that this glycan protects the CD4BS against antibodies.</p> <p>Conclusion</p> <p>The carbohydrate at position 386 is not essential for protein folding and function, but is involved in the protection of the CD4BS from antibodies. Removal of this sugar in the context of trimeric Env immunogens may therefore improve the elicitation of neutralizing CD4BS antibodies.</p

Statins Disrupt CCR5 and RANTES Expression Levels in CD4(+) T Lymphocytes In Vitro and Preferentially Decrease Infection of R5 Versus X4 HIV-1

BACKGROUND: Statins have previously been shown to reduce the in vitro infection of human immunodeficiency virus type 1 (HIV-1) through modulation of Rho GTPase activity and lipid raft formation at the cell surface, as well as by disrupting LFA-1 incorporation into viral particles. PRINCIPLE FINDINGS: Here we demonstrate that treatment of an enriched CD4(+) lymphocyte population with lovastatin (Lov), mevastatin (Mev) and simvastatin (activated and non-activated, Sim(A) and Sim(N), respectively) can reduce the cell surface expression of the CC-chemokine receptor CCR5 (P<0.01 for Sim(A) and Lov). The lowered CCR5 expression was associated with down-regulation of CCR5 mRNA expression. The CC-chemokine RANTES protein and mRNA expression levels were slightly increased in CD4(+) enriched lymphocytes treated with statins. Both R5 and X4 HIV-1 were reduced for their infection of statin-treated cells; however, in cultures where statins were removed and where a decrease in CCR5 expression was observed, there was a preferential inhibition of infection with an R5 versus X4 virus. CONCLUSIONS: The results indicate that the modulation of CC-chemokine receptor (CCR5) and CC-chemokine (RANTES) expression levels should be considered as contributing to the anti-viral effects of statins, preferentially inhibiting R5 viruses. This observation, in combination with the immunomodulatory activity exerted by statins, suggests they may possess more potent anti-HIV-1 activity when applied during the early stages of infection or in lowering viral transmission. Alternatively, statin treatment could be considered as a way to modulate immune induction such as during vaccination protocols

Isolation, Purification, and Biological Activity of Secondary Metabolites from Trichoderma asperellum F-1087

The secondary peptide metabolites produced by the Trichoderma asperellum strain F-1087 were isolated, and their properties were studied. It has been shown these metabolites at concentrations of 0.08 and 0.02 mg/mL inhibit the human prostate cancer cell line by 97 and 34%, respectively