Time and space waveform optimization to extend the harmonic cutoff and to produce the water window single attosecond pulse

Based on the three-step theory of high-order harmonic generation, the harmonic cutoff is very sensitive to the few-cycle laser waveform in both time and space regions. Therefore, in this paper, we propose the method to control the harmonic cutoff and to produce the water window attosecond pulse through the optimization of time and space waveform. It is found that, in the time region, by properly choosing the delay and phase of the few-cycle two-color pulse, not only the harmonic intensity is enhanced, but also the quantum path of the harmonic emission can be controlled. Further, with the introduction of the 3rd pulse (i.e., the infrared pulse or the unipolar pulse), the harmonic cutoff from the single harmonic emission peak can be extended, showing a water window harmonic plateau. In the space region, by using the positive spatial inhomogeneous effect, the harmonic cutoff from the basic two-color waveform can also be extended, which leads to a water window spectral continuum. Finally, by Fourier transformation of harmonics during the water window region, the ultrashort single 29 as pulses can be obtained.

New Irregular Mesh Technique Used in Three-Dimensional Simulation of Relaxation Semiconductors

The aim of this work is to simulate correctly in 3D space the phenomena that govern relaxation semiconductors. To avoid the relevant constraints of inadequate mesh a new technique for refining irregular meshing has been creating. Each length of the sample will be considered as a partial sum of a geometric series, the calculation of the argument of this series, will allow to calculate the distance between the nodes. In this paper we proposed to use an algorithm combined between Gummel and Newton Raphson algorithms to solve the partial differential equations, the linearization of transport equations is obtained by applying the finite difference method, which allowed us to calculate the relaxation time, life time and recombination rate. The results revealed appearance of a limited region called recombination front instead of charge space region, an improvement in computational time with a big precision for a 3D simulation, by letting to the user the choice of the distance to be discreet and the number of points wished without saturate the memory. This type of meshing is simple to apply and can be used to be applied as a solution to correctly simulate phenomena in structures at different areas for all the dimensions.

Gauge invariant target space entanglement in D-brane holography

It has been suggested in arXiv:2004.00613 that in Dp-brane holography, entanglement in the target space of the D-brane Yang-Mills theory provides a precise notion of bulk entanglement in the gravity dual. We expand on this discussion by providing a gauge invariant characterization of operator sub-algebras corresponding to such entanglement. This is achieved by finding a projection operator which imposes a constraint characterizing the target space region of interest. By considering probe branes in the Coloumb branch we provide motivation for why the operator sub-algebras we consider are appropriate for describing a class of measurements carried out with low-energy probes in the corresponding bulk region of interest. We derive expressions for the corresponding Renyi entropies in terms of path integrals which can be directly used in numerical calculations.

Atg39 links and deforms the outer and inner nuclear membranes in selective autophagy of the nucleus

In selective autophagy of the nucleus (hereafter nucleophagy), nucleus-derived double membrane vesicles (NDVs) are formed, sequestered within autophagosomes, and delivered to lysosomes or vacuoles for degradation. In Saccharomyces cerevisiae, the nuclear envelope (NE) protein Atg39 acts as a nucleophagy receptor, which interacts with Atg8 to target NDVs to forming autophagosomal membranes. In this study, we revealed that Atg39 is anchored to the outer nuclear membrane (ONM) via its transmembrane domain and also associated with the inner nuclear membrane (INM) via membrane-binding amphipathic helices (APHs) in its perinuclear space region, thereby linking these membranes. We also revealed that overaccumulation of Atg39 causes the NE to protrude towards the cytoplasm, and the tips of the protrusions are pinched off to generate NDVs. The APHs of Atg39 are crucial for Atg39 assembly in the NE and subsequent NE protrusion. These findings suggest that the nucleophagy receptor Atg39 plays pivotal roles in NE deformation during the generation of NDVs to be degraded by nucleophagy.

Nested Kriging Surrogates for Rapid Multi-Objective Optimization of Compact Microwave Components

A procedure for rapid EM-based multi-objective optimization of compact microwave components is presented. Our methodology employs a recently developed nested kriging modelling to identify the search space region containing the Pareto-optimal designs, and to construct a fast surrogate model. The latter permits determination of the initial Pareto set, further refined using a separate surrogate-assisted process. As an illustration, a three-section impedance transformer is designed for the best matching and minimum size. The set of trade-off designs is produced at the low computational cost of only a few hundred of high-fidelity EM simulations of the transformer circuit despite a large number of its geometry parameters.

Low-Cost Surrogate Modeling of Miniaturized Microwave Components Using Nested Kriging

In the paper, a recently reported nested kriging methodology is employed for modeling of miniaturized microwave components. The approach is based on identifying the parameter space region that contains high-quality designs, and, subsequently, rendering the surrogate in this subset. The results obtained for a miniaturized unequal-power-split rat-race coupler and a compact three-section impedance transformer demonstrate reliability of the method even for highly-dimensional parameter spaces, as well as its superiority over conventional modeling methods.

DIRECT AND INVERSE PROBLEMS FOR THERMAL GROOVING BY SURFACE DIFFUSION WITH TIME DEPENDENT MULLINS COEFFICIENT

We consider the Mullins’ equation of a single surface grooving when the surface diffusion is not considered as very slow. This problem can be formed by a surface grooving of profiles in a finite space region. The finiteness of the space region allows to apply the Fourier series analysis for one groove and also to consider the Mullins coefficient as well as slope of the groove root to be time-dependent. We also solve the inverse problem of finding time-dependent Mullins coefficient from total mass measurement. For both of these problems, the grooving side boundary conditions are identical to those of Mullins, and the opposite boundary is accompanied by a zero position and zero curvature which both together arrive at self adjoint boundary conditions.

Hrvatski problem s regionalizmom

Due to its geographic position and historical circumstances, Croatia is a country of deep regional differences. In this paper I try to remind the reader, on the one hand, of the inevitability of the regional perspective in approaching certain periods and, on the other hand, to find the answer to why regionalism can appear as an unpleasant methodology (and a fact?). I will refer to the terms related to regional narrative: geopoetics, regiopoetics, locality, glocality, homeland, boundaries, and so on, as well as the interrelationship of regional discourse with a discourse of memory and identity. The new regionalism (seems to me ‒ insufficiently present in Croatian literary research) as a part of cultural geography and cultural-anthropological research in cultural texts, explores the record of spatial experience and representation of space (region), as well as traces of action in the opposite direction: how a text of literature/culture influences the local context.