Hydroxylated oxanes as xyloside analogs for determination of the minimal binding requirements of β4GalT7

β-1,4-Galactosyltransferase 7 (β4GalT7) is a key enzyme in the biosynthesis of glycosaminoglycan (GAG) chains. Natural and synthetic xylosides can be used to both inhibit and prime GAG synthesis by acting as inhibitors or substrates for β4GalT7. In this report, we exploit hydroxylated oxanes as deoxygenated xyloside analogs to clarify the minimum protein-ligand interactions required for galactosylation and/or inhibition. Enantiomerically pure substances were synthesized using a chiral pool approach whereas the corresponding racemates were obtained from simple starting materials. The results of a β4GalT7 assay show that a single hydroxyl group on an oxane ring is insufficient to induce galactosylation or inhibition, which implies that at least two substituents, one of which being 3-OH, needs to be present.     

Robust planning of blending activities at refineries

Refinery operation planning is a complex task since refinery processes and inventories are tightly interconnected. We study refinery planning when ships are loaded with a blend of components and where arrival times of ships are uncertain. Any delay in ship arrival may result in overfull component tanks which results in less efficient blending alternatives, reduced process operations or even shut downs. We propose a planning approach where we use robust optimization as a decision tool. By using robust optimization uncertainty in arrival times is explicitly dealt with and the resulting plan and schedule will always be feasible. The approach includes a flexible way to describe and model uncertainties. To compare the robust approach with a traditional deterministic approach, we use a simulation process. Computational results from a case study and simulations show that the proposed methodology is substantially better than a deterministic approach.     

Geometry of Black Hole Thermodynamics

The Hessian of the entropy function can be thought of as a metric tensor on the state space. In the context of thermodynamical fluctuation theory Ruppeiner has argued that the Riemannian geometry of this metric gives insight into the underlying statistical mechanical system; the claim is supported by numerous examples. We study this geometry for some families of black holes. It is flat for the BTZ and Reissner–Nordström black holes, while curvature singularities occur for the Reissner–Nordström–anti–de Sitter and Kerr black holes.     

Wess–Zumino actions and Dirichlet boundary conditions for super p-branes with exotic fractions of supersymmetry

The general solutions in the models of closed and open superstring and super p-branes with exotic fractions of the N=1 supersymmetry are considered and the spontaneously broken character of the OSp(1,2M) symmetry of the models is established. It is shown that extending these models by Wess–Zumino terms generates the Dirichlet boundary conditions for superstring and super p-branes. Using the generalized Wess–Zumino terms new OSp(1,2M)-invariant super p-brane and Dp-brane-like actions preserving (M−1)/M fraction of supersymmetry are proposed. For M=32 these models suggest new superbrane vacua of M-theory preserving 31 from 32 global supersymmetries.     

High-resolution digital transmission microscopy—a Fourier holography approach

A spherical reference field is used to construct a digital holographic system with a demonstrated resolution up to 228 line pairs per mm. The reference field originates from a GRIN lens placed 1 mm from the illuminated object. This allows the use of a standard sensor to record the hologram with the required numerical aperture. The image is determined by evaluation of the Rayleigh–Sommerfeld diffraction integral that relates the object field in the image plane to the object field in the sensor plane. Experimental results are given for two charge coupled device sensors and one complementary metal-oxide-semiconductor active pixel sensor.     

On non-negatively curved metrics on open five-dimensional manifolds

Let V ⁿ be an open manifold of non-negative sectional curvature with a soul Σ of co-dimension two. The universal cover of the unit normal bundle N of the soul in such a manifold is isometric to the direct product M ^n-2 × R. In the study of the metric structure of V ⁿ an important role plays the vector field X which belongs to the projection of the vertical planes distribution of the Riemannian submersion on the factor M in this metric splitting . The case n = 4 was considered in [Gromoll, D., Tapp, K.: Geom. Dedicata 99, 127–136 (2003)] where the authors prove that X is a Killing vector field while the manifold V ⁴ is isometric to the quotient of by the flow along the corresponding Killing field. Following an approach of [Gromoll, D., Tapp, K.: Geom. Dedicata 99, 127–136 (2003)] we consider the next case n = 5 and obtain the same result under the assumption that the set of zeros of X is not empty. Under this assumption we prove that both M ³ and Σ³ admit an open-book decomposition with a bending which is a closed geodesic and pages which are totally geodesic two-spheres, the vector field X is Killing, while the whole manifold V ⁵ is isometric to the quotient of by the flow along corresponding Killing field. Supported by the Faculty of Natural Sciences of the Hogskolan i Kalmar (Sweden).     

Time-domain measurements of S-branch N2–N2 Raman linewidths using picosecond pure rotational coherent anti-Stokes Raman spectroscopy

Time-resolved dual-broadband picosecond pure rotational CARS has been applied to measure self-broadened S-branch N₂–N₂ Raman linewidths in the temperature range 294–1466 K. The coherence decays were detected directly in the time domain by following the J-dependent CARS signal decay as a function of probe delay. The rotational Raman N₂–N₂ linewidths were derived from these time-dependent decays and evaluated for thermometric accuracy. Comparisons were made to the energy-corrected sudden (ECS) and modified exponential gap (MEG) dynamical scaling laws, and the results were used to quantify the sensitivity of nanosecond rotational CARS thermometry to the linewidth model employed. The uncertainty based on the linewidth model used in pure N₂ was found to be 2 %. The merits and limitations of this rapid method for the determination of accurate Raman linewidths are discussed.     

On the analogy between backbending in gauge space and in ordinary space

The interplay between angular momentum and particle number (which is the equivalent to the angular momentum in gauge space) is studied. The same technique that is used in the case of rotations in ordinary space can be used in gauge space for investigating the properties of individual quasiparticle levels and the total angular momentum of a nucleus. We study the isotopes of Dy and W, where a back- or upbending behaviour is observed in gauge space around neutron number 86–88 (depending on the spin) and 108, respectively.