Kardioloogia

Eesti Arst 2012; 91(9):507–50

History as Communication in the works of Tartu-Moscow Schoool

[Abstract] The aim of this presentation will be to try and find a common ground between the cultural semiotics of the Tartu-Moscow school and the Western semiotic tradition which has greatly been influenced by Charles Peirce. I will concentrate on the works of Yuri Lotman and Boriss Uspensky, and try to bring out both the similarities and differences in their approaches. Lotman finds that human culture can be treated both as the sum of messages circulated by various addressers and as one message transmitted by the collective “I” if the humanity itself; from this point of view, culture can be viewed as a vast example of autocommunication, where information transferred in time from an earlier “I” to a later one leads to a restructuring of the “I” itself. For Uspensky, semiotic approach to history presupposes appealing to the point of view of the participants in the historical process: only those things are meaningful that are meaningful from their point of view. This approach, in turn, presupposes reconstructing the conceptual system that determines both the perception of certain events and the reaction to these events. This applies both to individuals and larger social groups, such as cultures. From the semiotic perspective, then, the historical process can be viewed as a process of communication where new information that is constantly created causes a certain reaction on the side of the receiver (the social group). Historical experience, in turn, influences the future turn of events: based on similar concepts and experiences, the society as a collective personality creates a program for the future and plans its future behavior. Every step in the movement of history changes both the present and the past, and with this also the future turn of event

CHARACTERIZATION OF ZERO MASS FLUX FLOW CONTROL FOR LOW SPEED AIRFOIL SEPARATION CONTROL

An adaptive wing, a zero mass ux ow control device for low speed airfoil separation control, is investigated both experimentally and computationally at low speeds. The adaptive mechanism in the wings provides variable camber that can be actuated across a range of frequencies and amplitudes. Piezoelectric actuators are housed in a NACA 4415 airfoil with a chord length of :203 m. The entire adaptive wing assembly is then wrapped under a layer of latex membrane to provide a exible and smooth upper surface pro le. Experimental diagnostics include ow visualization, particle image velocimetry, as well as lift and drag measurements. The numerical simulation uses a 2D incompressible CFD code based on a nite-volume structured formulation with a chimera overset grid for the purpose of parallel computing. In the current study, the dimensionless speed range examined is 2:5 104 Re 1:5 105, where particular focus is given to Re 7:5 104, where Re = U` . All experiments and simulations are conducted in the range of attack angles from 0 24 and between reduced frequency values from 0 f+ 1:09, where f+ = f` U1 . Both experimental and computational results show that the region of separation is reduced when the actuation is turned on, thus enhancing aerodynamic e ciency. The maximum coe cient of lift increases by 26% when the reduced frequency, f+, is approximately :2, where the ow control mechanism appears to be most e ective. Phase-locked PIV and CFD vorticity plots reveal that the downward motion of the surface actuation decelerates the boundary ow and increases surface pressure, resulting in the formation of a series of cross-stream vortices that provides uid entrainment towards the suction surface, hence reducing separation

DEPTH: a web server to compute depth and predict small-molecule binding cavities in proteins

Depth measures the extent of atom/residue burial within a protein. It correlates with properties such as protein stability, hydrogen exchange rate, protein–protein interaction hot spots, post-translational modification sites and sequence variability. Our server, DEPTH, accurately computes depth and solvent-accessible surface area (SASA) values. We show that depth can be used to predict small molecule ligand binding cavities in proteins. Often, some of the residues lining a ligand binding cavity are both deep and solvent exposed. Using the depth-SASA pair values for a residue, its likelihood to form part of a small molecule binding cavity is estimated. The parameters of the method were calibrated over a training set of 900 high-resolution X-ray crystal structures of single-domain proteins bound to small molecules (molecular weight <1.5 KDa). The prediction accuracy of DEPTH is comparable to that of other geometry-based prediction methods including LIGSITE, SURFNET and Pocket-Finder (all with Matthew’s correlation coefficient of ∼0.4) over a testing set of 225 single and multi-chain protein structures. Users have the option of tuning several parameters to detect cavities of different sizes, for example, geometrically flat binding sites. The input to the server is a protein 3D structure in PDB format. The users have the option of tuning the values of four parameters associated with the computation of residue depth and the prediction of binding cavities. The computed depths, SASA and binding cavity predictions are displayed in 2D plots and mapped onto 3D representations of the protein structure using Jmol. Links are provided to download the outputs. Our server is useful for all structural analysis based on residue depth and SASA, such as guiding site-directed mutagenesis experiments and small molecule docking exercises, in the context of protein functional annotation and drug discovery

Module Encapsulation Materials, Processing and Testing

Study of PV module encapsulation materials, processing, and testing shows that overall module reliability is determined by all component materials and processing factors

INFRARED SPECTRUM OF (Z)-3-IODO-BUT-2-EN-1-YL [• CH2CHC(CH3)I] PRODUCED UPON PHOTODISSOCIATION OF (Z)-1,3-DIIODO-BUT-2-ENE [(CH2I) HC=C(CH3)I] IN SOLID PARA-HYDROGEN

Isoprene is the most abundant volatile organic compound (VOC) in the Earth’s atmosphere after methane. Ozonolysis of isoprene, with the production of the Criegee intermediate methyl vinyl ketone oxide (MVKO), plays an important role in atmospheric chemistry. Recently, Barber \textit{et al.}\footnote{V. P. Barber \textit{et al.} J. Am. Chem. Soc., \textbf{140}, 10866-10880 (2018).} photolyzed 1,3-diiodo-but-2-ene [\chem{(CH_2I)HC=C(CH_3)I}] in the presence of O$_2$ with UV light and identified the Criegee intermediate \textit{syn-trans-}MVKO as the main reaction product. However, the detailed mechanism for the production of MVKO is unexplored. It was assumed that photolysis of \chem{(CH_2I)HC=C(CH_3)I} at 248 nm results in preferential dissociation of the weaker allylic C$_{(1)}$--I bond, rather than the vinylic (sp$^{2}$-hybridized) C$_{(3)}$--I bond. Addition of O$_2$ to the C$_{(3)}$ atom, followed by breaking the C$_{(3)}$--I bond, produces the Criegee intermediate MVKO.\\ In this work we took the advantege of the diminished cage effect of solid \textit{para-}hydrogen (\textit{p-}H$_2$) as a matrix host to study the UV photodissociation of \chem{\textit{(Z)-}(CH_2I)HC=C(CH_3)I}. We report the formation and infrared identification of \textit{(Z)-}3-iodo-but-2-en-1-yl [\chem{\bullet CH_2CHC(CH_3)I}] radical intermediate upon photodissociation of \chem{\textit{(Z)-}(CH_2I)HC=C(CH_3)I} in solid \textit{p-}H$_2$ at 3.3 K with light at 280 nm. Lines at 3115.6, 2025.2, 3001.2, 2933.2, 2880.3, 2835.8, 1474.9, 1409.6, 1406.7, 1375.5, 1265.3, 1061.8, 1018.5, 1008.6, 922.0, 913.7, and 792.5 cm$^{-1}$ are assigned to \chem{\textit{(Z)-}\bullet CH_2CHC(CH_3)I}. The assignments were derived according to behavior on secondary photolysis and comparison of the vibrational wavenumbers and the IR intensities of the observed lines with values predicted with the B2PLYP-D3/cc-pVTZ-pp method. No evidence of breakage of the C$_{(3)}$--I bond to form \chem{\bullet C(CH_3)=C(CH_2I)H} was observed

Development of an Accelerated Weathering Protocol using Weatherometers for Reliability Study of Mini-Modules and Encapsulation Materials

This paper describes the needs, reasoning, approaches, and technical details to establish a practical accelerated weathering test (AWT) protocol for indoor testing of the photothermal stability of encapsulation materials and encapsulated solar cells and minimodules

Infrared identification of the criegee intermediate (CH3)2COO

The Criegee intermediates are carbonyl oxides that play critical roles in ozonolysis of alkenes in the atmosphere. We reported previously the mid-infrared spectra of the simplest Criegee intermediate \chem{CH_2OO}.\footnote { Y.-T. ~Su, Y.-H. ~Huang, H. A. ~Witek, Y.-P. ~Lee, \textit{Science} \underline{\textbf{340}}, 174 (2013).}$^{,}$ \footnote { Y.-H. ~Huang, J. ~Li, H. ~Guo, Y.-P. ~Lee, \textit{J. Chem. Phys.} \underline{\textbf{142}}, 214301 (2015).} and the methyl-substituted intermediate \chem{CH_3CHOO}.\footnote { H.-Y. ~Lin, Y.-H. ~Huang, X. ~Wang, J. M. ~Bowman, Y. ~Nishimura, H. A. ~Witek, Y.-P. ~Lee, \textit{Nat. Comm.} \underline{\textbf{6}}, 7012 (2015).} Here we report the transient infrared spectrum of \chem{(CH_3)_2COO}, produced on UV photolysis of a mixture of \chem{(CH_3)_2CI_2}, \chem{N_2}, and \chem{O_2} in a flow reactor, using a step-scan Fourier-transform spectrometer. Guided by results of quantum-chemical calculations, rotational contours of the four observed bands are simulated successfully and provide definitive identification of \chem{(CH_3)_2COO}. Although all observed bands of \chem{(CH_3)_2COO} contain hot bands from four vibrational modes of low energy, we were able to simulate the spectra satisfactorily. Observed bands with origins near 887, 1040, 1368, and 1422 cm$^{-1}$ agree satisfactorily with corresponding anharmonic vibrational wavenumbers at 903, 1061, 1364, and 1422 cm$^{-1}$ predicted with the B3LYP/aug-cc-pVTZ method. Furthermore, we could also estimate the rate coefficient of the self-reaction of \chem{(CH_3)_2COO}. The direct infrared detection of \chem{(CH_3)_2COO} should prove useful for future field measurements and laboratory investigations of this Criegee intermediate

INFRARED SPECTRUM OF N-OXIDOHYDROXYLAMINE [•ONH(OH)] PRODUCED IN REACTION H + HONO IN SOLID PARA-HYDROGEN

Hydrogenation reactions in the N/O chemical network are important for an understanding of the mechanism of formation of organic molecules in dark interstellar clouds, but many reactions remain unknown. We present the results of the reaction H + HONO in solid ${para}$-hydrogen (${p}$-H$_{2}$) at 3.3 K investigated with infrared spectra. Two methods that produced hydrogen atoms were the irradiation of HONO molecules in ${p}$-H$_{2}$ at 365 nm to produce OH radicals that reacted readily with nearby H$_{2}$ to produce mobile H atoms, and irradiation of Cl$_{2}$ molecules (co-deposited with HONO) in ${p}$-H$_{2}$ at 405 nm to produce Cl atoms that reacted readily with nearby H$_{2}$ to produce mobile H atoms. In both experiments, we assigned IR lines at 3549.6 (nub{1}), 1465.0 (nub{3}), 1372.2 (nub{4}), 895.6/898.5 (nub{6}), and 630.9 (nub{7}) wn to N-oxidohydroxylamine [•ONH(OH)], the primary product of HONO hydrogenation. The assignments were derived according to the consideration of possible reactions and comparison of observed vibrational wavenumbers and their IR intensities with values predicted with the B3LYP/aug-cc-pVTZ method of quantum-chemical calculations. The agreement between observed and calculated D/H- and $^{15}$N/$^{14}$N-isotopic ratios further supports these assignments. The role of this reaction in the N/O chemical network in dark interstellar clouds is discussed