The Function of Sialidase Revealed by Sialidase Activity Imaging Probe

Sialidase cleaves sialic acid residues from glycans such as glycoproteins and glycolipids. In the brain, desorption of the sialic acid by sialidase is essential for synaptic plasticity, learning and memory and synaptic transmission. BTP3-Neu5Ac has been developed for sensitive imaging of sialidase enzyme activity in mammalian tissues. Sialidase activity in the rat hippocampus detected with BTP3-Neu5Ac increases rapidly by neuronal depolarization. It is presumed that an increased sialidase activity in conjunction with neural excitation is involved in the formation of the neural circuit for memory. Since sialidase inhibits the exocytosis of the excitatory neurotransmitter glutamate, the increased sialidase activity by neural excitation might play a role in the negative feedback mechanism against the glutamate release. Mammalian tissues other than the brain have also been stained with BTP3-Neu5Ac. On the basis of information on the sialidase activity imaging in the pancreas, it was found that sialidase inhibitor can be used as an anti-diabetic drug that can avoid hypoglycemia, a serious side effect of insulin secretagogues. In this review, we discuss the role of sialidase in the brain as well as in the pancreas and skin, as revealed by using a sialidase activity imaging probe. We also present the detection of influenza virus with BTP3-Neu5Ac and modification of BTP3-Neu5Ac.     

Effects of SO2 on selective catalytic reduction of NO with NH3 over a TiO2 photocatalyst

The effect of SO₂ gas was investigated on the activity of the photo-assisted selective catalytic reduction of nitrogen monoxide (NO) with ammonia (NH₃) over a TiO₂ photocatalyst in the presence of excess oxygen (photo-SCR). The introduction of SO₂ (300 ppm) greatly decreased the activity of the photo-SCR at 373 K. The increment of the reaction temperature enhanced the resistance to SO₂ gas, and at 553 K the conversion of NO was stable for at least 300 min of the reaction. X-ray diffraction, FTIR spectroscopy, thermogravimetry and differential thermal analysis, x-ray photoelectron spectroscopy (XPS), elemental analysis and N₂ adsorption measurement revealed that the ammonium sulfate species were generated after the reaction. There was a strong negative correlation between the deposition amount of the ammonium sulfate species and the specific surface area. Based on the above relationship, we concluded that the deposition of the ammonium sulfate species decreased the specific surface area by plugging the pore structure of the catalyst, and the decrease of the specific surface area resulted in the deactivation of the catalyst.     

Direct Injection of CRISPR/Cas9-Related mRNA into Cytoplasm of Parthenogenetically Activated Porcine Oocytes Causes Frequent Mosaicism for Indel Mutations

Some reports demonstrated successful genome editing in pigs by one-step zygote microinjection of mRNA of CRISPR/Cas9-related components. Given the relatively long gestation periods and the high cost of housing, the establishment of a single blastocyst-based assay for rapid optimization of the above system is required. As a proof-of-concept, we attempted to disrupt a gene (GGTA1) encoding the α-1,3-galactosyltransferase that synthesizes the α-Gal epitope using parthenogenetically activated porcine oocytes. The lack of α-Gal epitope expression can be monitored by staining with fluorescently labeled isolectin BS-I-B₄ (IB4), which binds specifically to the α-Gal epitope. When oocytes were injected with guide RNA specific to GGTA1 together with enhanced green fluorescent protein (EGFP) and human Cas9 mRNAs, 65% (24/37) of the developing blastocysts exhibited green fluorescence, although almost all (96%, 23/24) showed a mosaic fluorescent pattern. Staining with IB4 revealed that the green fluorescent area often had a reduced binding activity to IB4. Of the 16 samples tested, six (five fluorescent and one non-fluorescent blastocysts) had indel mutations, suggesting a correlation between EGFP expression and mutation induction. Furthermore, it is suggested that zygote microinjection of mRNAs might lead to the production of piglets with cells harboring various mutation types.     

Liquid Marble Patchwork on Super-Repellent Surface

Liquid marble (LM) is a droplet that is wrapped by hydrophobic solid particles, which behave as a non-wetting soft solid. Based on these properties, LM can be applied in fluidics and soft device applications. A wide variety of functional particles have been synthesized to form functional LMs. However, the formation of multifunctional LMs by integrating several types of functional particles is challenging. Here, a general strategy for the flexible patterning of functional particles on droplet surfaces in a patchwork-like design is reported. It is shown that LMs can switch their macroscopic behavior between a stable and active state on super-repellent surfaces in situ by jamming/unjamming the surface particles. Active LMs hydrostatically coalesce to form a self-sorted particle pattern on the droplet surface. With the support of LM handling robotics, on-demand cyclic activation–manipulation–coalescence–stabilization protocols by LMs with different sizes and particle types result in the reliable design of multi-faced LMs. Based on this concept, a single bi-functional LM is designed from two mono-functional LMs as an advanced droplet carrier.     

Integration of imitation learning using GAIL and reinforcement learning using task-achievement rewards via probabilistic graphical model

The integration of reinforcement learning (RL) and imitation learning (IL) is an important problem that has long been studied in the field of intelligent robotics. RL optimizes policies to maximize the cumulative reward, whereas IL attempts to extract general knowledge about the trajectories demonstrated by experts, i.e, demonstrators. Because each has its own drawbacks, many methods combining them and compensating for each set of drawbacks have been explored thus far. However, many of these methods are heuristic and do not have a solid theoretical basis. This paper presents a new theory for integrating RL and IL by extending the probabilistic graphical model (PGM) framework for RL, control as inference. We develop a new PGM for RL with multiple types of rewards, called probabilistic graphical model for Markov decision processes with multiple optimality emissions (pMDP-MO). Furthermore, we demonstrate that the integrated learning method of RL and IL can be formulated as a probabilistic inference of policies on pMDP-MO by considering the discriminator in generative adversarial imitation learning (GAIL) as an additional optimality emission. We adapt the GAIL and task-achievement reward to our proposed framework, achieving significantly better performance than policies trained with baseline methods.     

Hydrogel photocatalysts for efficient energy conversion and environmental treatment

Photocatalysts have attracted great research interest owing to their excellent properties and potential for simultaneously addressing challenges related to energy needs and environmental pollution. Photocatalytic particles need to be in contact with their respective media to exhibit efficient photocatalytic performances. However, it is difficult to separate nanometer-sized photocatalytic materials from reaction media later, which may lead to secondary pollution and a poor recycling performance. Hydrogel photocatalysts with a three-dimensional (3D) network structures are promising support materials for photocatalysts based on features such as high specific surface areas and adsorption capacities and good environmental compatibility. In this review, hydrogel photocatalysts are classified into two different categories depending on their elemental composition and recent progresses in the methods for preparing hydrogel photocatalysts are summarized. Moreover, current applications of hydrogel photocatalysts in energy conversion and environmental remediation are reviewed. Furthermore, a comprehensive outlook and highlight future challenges in the development of hydrogel photocatalysts are presented.     

A low-resistance self-aligned T-shaped gate for high-performancesub-0.1-μm CMOS

This paper describes the high performance of T-shaped-gate CMOS devices with effective channel lengths in the sub-0.1-μm region. These devices were fabricated by using selective W growth, which allows low-resistance gates smaller than 0.1 μm to be made without requiring fine lithography alignment. We used counter-doping to scale down the threshold voltage while still maintaining acceptable short-channel effects. This approach allowed us to make ring oscillators with a gate-delay time as short as 21 ps at 2 V with a gate length of 0.15 μm. Furthermore, we experimentally show that the high circuit speed of a sub-0.1-μm gate length CMOS device is mainly due to the PMOS device performance, especially in terms of its drivability     

High performance liquid chromatographic separation of diacylglycerol acetates to quantitate disaturated species of lung phosphatidylcholine

A high-performance liquid chromatographic (HPLC) separation of diacylglycerol acetates to quantitatite disaturated species of lung phosphatidylcholine (PC) was studied. The diacylglycerol acetates were applied on a reversed phase column, eluted by an isocratic solvent, acetonitrile/isopropanol/water (35:15:1, v/v/v) at a flow rate of 1 ml/min, and detected by differential refractometry (RI). This isocratic HPLC method was useful to separate disaturated species from the others of lung PC. The quantitative analysis of the molecular species separated by HPLC was studied by RI detection. Chroamtograms obtained by RI detection and radioactivity determination of diacylglycerol [³H]acetates prepared by [³H]acetic anhydride were almost identical. The RI detector responsed in the same degree for different, authentic standards of diacylglycerol acetates. The detection limit with RI detection was about 30 nmoles. Molecular species of PCs from human lung and carcinoma tissues were analyzed by this HPLC method. The contents of disaturated species were very similar to those reported previously. These results indicate that RI detection is very useful in the nmole range for the quantitative analysis among the molecular species containing disaturated species.     

Carbonization of coals into anisotropic cokes: 7. Copreheat-treatment under short contact-time conditions at high temperature

The copreheat-treatment of non-fusible and slightly fusible coals with A240 and hydrogenated A240 under high temperature-short contact-time conditions around 500 °C has been examined in an attempt to produce a formed coke with better anisotropic development. These conditions shortened the copreheat-treatment time and provided better anisotropic development in the resultant coke after carbonization. Effectiveness of short contact-time has been discussed in terms of the extent of depolymerization of coal molecules suitable for anisotropic development, this being related to coal liquefaction under similar conditions.