Reactivation of Anticancer Immunity by Resetting Interorgan Crosstalk in Immune-Suppressive Cells with a Nanoparticulated Anti-Inflammatory Drug

The reactivation of anticancer immunity is a fundamental principle in cancer immunotherapy as evidenced by the use of immune checkpoint inhibitors (ICIs). While treatment with the ICIs is shown to have remarkable and durable therapeutic effects in the responders, the low objective response rate (<40%) continues to be a major problem. Since myeloid-derived suppressor cells (MDSCs), heterogenous cells with strong immunosuppressive activity that originate in the hematopoietic system, suppress the anticancer immunity via parallel immune checkpoint-dependent and independent pathways, these cells are potential targets for improving the efficacy of cancer immunotherapy. In this study, it is demonstrated that MDSCs can be depleted by delivering synthetic glucocorticoid dexamethasone to phagocytic cells in the spleen using a lipid nanoparticle. Since the interaction of nanoparticles with T cells is intrinsically poor, this strategy also enables the “detargeting” from T cells, thus avoiding the nonspecific suppression of cytotoxic immune responses against cancer cells. In addition to the direct anticancer effect of the nanoparticulated dexamethasone, their synergistic anticancer effect with ICIs is also reported.     

A three-dimensional shape optimization for transient acoustic scattering problems using the time-domain boundary element method

We develop a three-dimensional shape optimization (SO) framework for the wave equation with taking the unsteadiness into account. Resorting to the adjoint variable method, we derive the shape derivative (SD) with respect to a deformation (perturbation) of an arbitrary point on the target surface of acoustic scatterers. Successively, we represent the target surface with non-uniform rational B-spline patches and then discretize the SD in term of the associated control points (CPs), which are useful for manipulating a surface. To solve both the primary and adjoint problems, we apply the time-domain boundary element method (TDBEM) because it is the most appropriate when the analysis domain is the ambient air and thus infinitely large. The issues of the severe computational cost and instability of the TDBEM are resolved by exploiting the fast and stable TDBEM proposed by the present authors. Instead, since the TDBEM is mesh-based and employs the piecewise-constant element for space, we introduce some approximations in evaluating the discretized SD from the two solutions of TDBEM. By regarding the evaluation scheme as the computation of the gradient of the objective functional, given as the summation of the absolute value of the sound pressure over the predefined observation points, we can solve SO problems with a gradient-based non-linear optimization solver. To assess the developed SO system, we performed several numerical experiments from the perspective of verification and application with satisfactory results.     

Purely resistive load estimation for three-phase inverter by using pseudo random binary sequence signal

In recent years, the introduction of photovoltaic power generation systems has been increasing from the perspective of global warming countermeasures. However, there is a problem that it becomes difficult to adjust the supply and demand balance of electric power. Therefore, in this research, the inverter by using estimation signal estimates the load of the consumer, then we aim to adjust the supply-demand balance at the demand side. By the verification of experimental, three-phase inverter, which is assumed to be an industrial photovoltaic power generation system, estimates the load by using pseudo random binary sequence (PRBS) signal and two proposed methods. The load estimation results show that the error rate of the estimated resistance of each phase is within a few percent by using the two proposed methods, and the load estimation is achieved.     

Some Structural Characteristics of Starches of Maize Having a Specific Genetic Background

Distribution of starch components of maize (Zea mays L.) and their properties were investigated by gel filtration after debranching and by exhaustive hydrolysis of starch-granules with glucoamylase. Based on the results, relationship between genotypes and properties of starch components were discussed. The sugary-1 (su₁), sugary-2 (su₂), and dull (du) mutants produced high amylose maize, while amylopectin of su₂ was normal type and those of su₁ and du were novel type. In the double-mutant combinations, the waxy (wx) gene decreased amylose content. Starches of du su₁ or du su₂ possessed greatest amount of amylose among starches examined. Contents of amylose, intermediate fraction (Fr.) and longer branches of amylopectin increased in most cases when the amylose-extender (ae) gene was introduced. Starches of ae possessed longer average chain-lengths of amylopectin than that of normal. In ae du starches, however, elongation of the amylopectin chain and increase of the intermediate Fr. did not occur. Exhaustive degradation of starch-granules by glucoamylase showed that ae starches were more resistant to amylase.     

Single-atom microscopy in wide-bandgap nitrides

Wide bandgap III-nitrides, such as cubic boron nitride and wurtzite-type aluminum nitride, are promising systems for optoelectronics. To extend their luminescent properties, we doped single Ce atoms into III-nitride single crystals using reactive flux with a temperature gradient method at high-pressure and high-temperature conditions. To fully understand such properties in a large size-mismatch system, it is critically important to determine the point-defect structures of single dopants, their spatial distribution in three dimensions, and their atomistic dynamics at an atomic level. This review discusses point defect structures and their dynamics in III-nitrides using single-atom-sensitive scanning transmission electron microscopy, and the recent progress in the related field of electron microscopy.     

Size-Controlled Synthesis of Luminescent Few-Atom Silver Clusters via Electron Transfer in Isostructural Redox-Active Porous Ionic Crystals (Small 23/2023)

Ag clusters with a controlled number of atoms have received significant interest because they show size-dependent catalytic, optical, electronic, or magnetic properties. However, the synthesis of size-controlled, ligand-free, and air-stable Ag clusters with high yields has not been well-established. Herein, it is shown that isostructural porous ionic crystals (PICs) with redox-active polyoxometalates (POMs) can be used to synthesize Ag clusters via electron transfer from POMs to Ag⁺. Ag clusters with average numbers of three, four, or six atoms emitting blue, green, or red colors, respectively, are formed and stabilized in the PICs under ambient conditions without any protecting ligands. The cluster size solely correlates with the degree of electron transfer, which is controlled by the reduction time and types of ions or elements of the PICs. Thus, advantages have been taken of POMs as electron sources and PICs as scaffolds to demonstrate a convenient method to obtain few-atom Ag clusters.