New energy levels and transitions for the 4s4p5p configuration in Kr VI

The spectrum of five-time ionized krypton, Kr VI, was recorded in the 240-2600 Å wavelength range, resulting in 61 new classified lines as transitions between levels of configurations 4p³, 4s²5p, 4s4p4d, 4s4p5s and 4s4p5p. All the 18 energy levels belonging to 4s4p5p configuration except one were determined. Eight new energy level values corresponding to configurations 4s4p4f and 4p24d, supported by 26 new classified lines were also determined and used in the interpretation of the observed 4s4p5p configuration. The experimental data were obtained from a capillary-discharge tube and theta pinch light sources. Multiconfiguration Hartree-Fock calculations with relativistic corrections and a least-squares fitted parametric calculation has been carried out.     

Location Matters: Site of Conjugation Modulates Stability and Pharmacokinetics of Antibody Drug Conjugates

1. Download : Download high-res image (301KB)
2. Download : Download full-size image

Highlights? Site-specific conjugation of diverse payloads can be achieved with transglutaminase ? Efficient conjugation was achieved at multiple positions throughout an antibody ? Site of conjugation has significant impact on ADC stability and pharmacokinetics ? Differences in ADC stability and pharmacokinetics are species dependent     

On the Existence of Fixed Points for Approximate Value Iteration and Temporal-Difference Learning

Approximate value iteration is a simple algorithm that combats the curse of dimensionality in dynamic programs by approximating iterates of the classical value iteration algorithm in a spirit reminiscent of statistical regression. Each iteration of this algorithm can be viewed as an application of a modified dynamic programming operator to the current iterate. The hope is that the iterates converge to a fixed point of this operator, which will then serve as a useful approximation of the optimal value function. In this paper, we show that, in general, the modified dynamic programming operator need not possess a fixed point; therefore, approximate value iteration should not be expected to converge. We then propose a variant of approximate value iteration for which the associated operator is guaranteed to possess at least one fixed point. This variant is motivated by studies of temporal-difference (TD) learning, and existence of fixed points implies here existence of stationary points for the ordinary differential equation approximated by a version of TD that incorporates exploration.     

Magnetostatic modes in coupled antiferromagnet/ferromagnet bilayers

We study the influence of interface effects on the magnetostatic modes propagating in a coupled ferromagnetic/antiferromagnetic bilayer. We assume that the magnetic layers are thick enough to be described by the bulk parameters and they are coupled through the interaction between the magnetic moments located at the interface. We use a phenomenological approach taking into account the presence of different magnetic layers in the system to calculate the modified dynamical response of each material. We use the corrected magnetic permeability of the layers to obtain a correlation between the interface characteristics and the physical behavior of the magnetic excitations propagating in the system.     

Numerical investigation of the effect of soot aggregation on the radiative properties in the infrared region and radiative heat transfer

The effect of aggregation on soot radiative properties in the infrared region of the spectrum is numerically investigated using Rayleigh-Debye-Gans theory for fractal aggregates (RDG-FA). In order to use the RDG-FA theory for a wide range of aggregate sizes and wavelengths, the predicted phase functions, scattering and absorption coefficients are compared with a more accurate theory, the integral equation formulation for scattering—IEFS. The importance of scattering when compared with absorption is investigated, as well as the effect of aggregation on the phase function shape and on the scattering cross section. It is concluded that in the case of small aggregates formed with small primary particles the scattering coefficient is negligible compared with the absorption coefficient, and scattering and aggregation of primary particles can be ignored. Thus, the Rayleigh approximation can be used leading to isotropic scattering. In the case of large aggregates constituted by large primary particles, aggregation becomes important and the scattering cross section is of the same order of magnitude of the absorption cross section. Moreover, the phase function becomes highly peaked in the forward direction. Therefore, the Rayleigh and the equivalent volume Mie sphere approximations are not valid, and the RDG-FA method emerges as a good compromise between accuracy and simplicity of application. However, radiative transfer calculations between two infinite, parallel, black walls show that scattering may always be neglected in the calculation of total radiative heat source and heat fluxes to the walls. The minor influence of scattering on the accuracy of the predictions is explained by the shift between the spectral region where scattering is important and the region where the spectral radiative heat source is large.     

Branch-and-cut for separable piecewise linear optimization and intersection with semi-continuous constraints

We report and analyze the results of our computational testing of branch-and-cut for piecewise linear optimization using the cutting planes given recently by Zhao and de Farias. Besides evaluating the performance of the cuts, we evaluate the effect of formulation on the performance of branch-and-cut. Finally, we report and analyze results on piecewise linear optimization problems with semi-continuous constraints.     

Application of core-shell PEGylated CdS/Cd(OH)2 quantum dots as biolabels of Trypanosoma cruzi parasites

Semiconductor quantum dots are a promising class of materials in the labeling of biological systems. In the present study we show the marking pattern of Trypanosoma cruzi (T. cruzi) live parasites using PEGylated CdS/Cd(OH)₂ fluorescent nanocrystals. The analysis obtained by confocal fluorescence microscopy and transmission electron microscopy indicates that only the endocytic paths of parasites were labeled. The parasites were alive after the incubation with the CdS/Cd(OH)₂-PEG suspension. Labeling the T. cruzi with quantum dots can help to better understand the endocytosis process and also the cellular differentiation.     

New highly fluorescent biolabels based on II-VI semiconductor hybrid organic-inorganic nanostructures for bioimaging

Semiconductor quantum dots based on II-VI materials may be prepared to develop good biolabeling properties. In this study we present some well-succeeded results related to the preparation, functionalization and bioconjugation of CdY (Y = S, Se and Te) to biological systems (live cells and fixed tissues). These nanostructured materials were prepared using colloidal synthesis in aqueous media resulting nanoparticles with very good optical properties and an excellent resistance to photodegradation.