Atomic force microscopy (AFM) was used to study the structure of the staphylococcal alpha-hemolysin (alpha HL) oligomer formed in supported phospholipid bilayers. In contrast to the recent X-ray crystallographic demonstration of a heptameric stoichiometry for the oligomer formed in deoxycholate (DOC) micelles, the high-resolution unprocessed AFM images unequivocally revealed a hexamer in these ...

Complexes of double-stranded DNA with the cationic surfactant cetyltrimethylammonium bromide have been studied using small angle x-ray diffraction at varying concentrations of DNA and the cosurfactant hexanol. At low DNA concentrations, an intercalated hexagonal (H(c)(I))-->lamellar (L(c)(alpha))-->inverted hexagonal (H(c)(II)) transformation is found on increasing hexanol content. The H(c)(II)...

The structure of the complex between carboxypeptidase A alpha (EC 3.4.17.1) and the ketonic substrate analogue 5-benzamido-2-benzyl-4-oxopentanoic acid (BOP) has been determined by x-ray crystallographic methods to a resolution of 1.7 A (final R = 0.191). Interestingly, BOP was observed to bind to the active site of carboxypeptidase A alpha as the covalent hydrate adduct. Because BOP is probabl...

We are developing a kilo-pixels Ti/Au TES array as backup option for Athena X-IFU. Here we report on single-pixel performance of 32$\times$32 operated in Frequency Division Multiplexing (FDM) readout system, with bias frequencies the range 1-5 MHz. have tested pixels response at several photon energies, by means $^{55}$Fe radioactive source (emitting Mn-K$\alpha$ 5.9 keV) and Modulated X-ray So...

The $^{18}\mathrm{Ne}(\ensuremath{\alpha},p)^{21}\mathrm{Na}$ reaction plays a significant role in Type-I X-ray bursts. It is major path the breakout from hot-CNO cycles to synthesis of heavier elements $\ensuremath{\alpha}p$- and $rp$-processes. An experiment determine cross section this was performed with ANASEN active-target detector system, determining at energies between 2.5 4 MeV center-o...

The High Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory surveys the very high energy sky in 300 GeV to $>100$ TeV range. HAWC has detected two blazars above $11\sigma$, Markarian 421 (Mrk 421) and 501 501). observations are comprised of data taken period between June 2015 July 2018, resulting a $\sim 1038$ days exposure. In this work we report time-averaged spectral analysis for both sou...

The preparation of LiF targets on a self-supporting Ag backing (LiF/Ag) was discussed in detail using the vacuum evaporation process. fabricated were analyzed and efficiently characterized, with target thickness measured by energy loss alpha particles through target. estimated ∼0.63±0.09μm. non-uniformity thoroughly checked help collimator, within 6.50 %. surface morphology elemental compositio...