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The ongoing pandemic of global concern has killed about three million humans and affected around 151 million people worldwide, as of April 30, 2021. Although recently approved vaccines for COVID-19 are engendering hope, finding new ways to cure the viral pandemic is still a quest for researchers worldwide. Major pandemics in history have been of viral origin, such as SARS, MERS, H1NI, Spanish flu, and so on. A larger emphasis has been on discovering potential vaccines, novel antiviral drugs, and agents that can mitigate the viral infection symptoms; however, a relatively new area, RNA interference (RNAi), has proven effective as an antiviral agent. The RNAi phenomenon has been largely exploited to cure cancer, neurodegenerative diseases, and some rare diseases. The U.S. Food and Drug Administration has recently approved three siRNA products for human use that garner significant hope in siRNA therapeutics for coronaviruses. There have been some commentaries and communications addressing this area. We have summarized and illustrated the significance and the potential of the siRNA therapeutics available as of April 30, 2021 to combat the ongoing viral pandemic and the emerging new variants such as B.1.1.7 and B.1.351. Numerous successful in vitro studies and several investigations to address the clinical application of siRNA therapeutics provide great hope in this field. This seminal Review describes the significance of siRNA-based therapy to treat diverse viral infections in addition to the current coronavirus challenge. In addition, we have thoroughly reviewed the patents approved for coronaviruses, the major challenges in siRNA therapy, and the potential approaches to address them, followed by innovation and prospects.

Metal nanoclusters (NCs), which consist of several, to about one hundred, metal atoms, have attracted much attention as functional nanomaterials for use in nanotechnology. Because of their fine particle size, metal NCs exhibit physical/chemical properties and functions different from those of the corresponding bulk metal. In recent years, many techniques to precisely synthesize metal NCs have been developed. However, to apply these metal NCs in devices and as next-generation materials, it is necessary to assemble metal NCs to a size that is easy to handle. Recently, multiple techniques have been developed to form one-, two-, and three-dimensional connected structures (CSs) of metal NCs through self-assembly. Further progress of these techniques will promote the development of nanomaterials that take advantage of the characteristics of metal NCs. This review summarizes previous research on the CSs of metal NCs. We hope that this review will allow readers to obtain a general understanding of the formation and functions of CSs and that the obtained knowledge will help to establish clear design guidelines for fabricating new CSs with desired functions in the future.

Metal nanoclusters (NCs) have a particle size of about one nanometer, which makes them the smallest unit that can give a function to a substance. In addition, metal NCs possess physical and chemical properties that are different from those of the corresponding bulk metals. Metal NCs with such characteristics are expected to be important for use in nanotechnology. Research on the precise synthesis of metal NCs and elucidation of their physical/chemical properties and functions is being actively conducted. When metal NCs are alloyed, it is possible to obtain further various electronic and geometrical structures and functions. Thus, research on alloy NCs has become a hot topic in the study of metal NCs and the number of publications on alloy NCs has increased explosively in recent years. Such publications have provided much insight into the effects of alloying on the electronic structure and function of metal NCs. However, the rapid increase in knowledge has made it difficult for researchers (especially those new to the field) to grasp all of it. Therefore, in this review, we summarize the reported chemical composition, geometrical structure, electronic structure, and physical and chemical properties of Aun-x Mx (SR)m , Agn-x Mx (SR)m , Aun-x Mx (PR3 )l (SR)m , and Agn-x Mx (PR3 )l (SR)m (Au=gold, Ag=silver, M=heteroatom, PR3 =phosphine, and SR=thiolate) NCs. This review is expected to help researchers understand the characteristics of alloy NCs and lead to clear design guidelines to develop new alloy NCs with intended functions.

Plant complex-type N -glycans are characterized by the presence of α1,3-linked fucose towards the proximal N -acetylglucosamine residue and β1,2-linked xylose towards the β-mannose residue. These glycans are ultimately degraded by the activity of several glycoside hydrolases. However, the degradation pathway of plant complex-type N -glycans has not been entirely elucidated because the gene encoding α1,3-fucosidase, a glycoside hydrolase acting on plant complex-type N -glycans, has not yet been identified, and its substrate specificity remains to be determined. In the present study, we found that AtFUC1 (an Arabidopsis GH29 α-fucosidase) is an α1,3-fucosidase acting on plant complex-type N -glycans. This fucosidase has been known to act on α1,4-fucoside linkage in the Lewis A epitope of plant complex-type N -glycans. We found that this glycoside hydrolase specifically acted on GlcNAcβ1–4(Fucα1–3)GlcNAc, a degradation product of plant complex-type N -glycans, by sequential actions of vacuolar α-mannosidase, β1,2-xylosidase, and endo-β-mannosidase. The AtFUC1-deficient mutant showed no distinct phenotypic plant growth features; however, it accumulated GlcNAcβ1–4(Fucα1–3)GlcNAc, a substrate of AtFUC1. These results showed that AtFUC1 is an α1,3-fucosidase acting on plant complex-type N -glycans and elucidated the degradation pathway of plant complex-type N -glycans.

ETOC: Phosphorylation of KLC1 at Thr466 in kinesin-1 regulates the interaction with APP mediated by JIP1b. Substitution of Glu for Thr466 abolished this interaction and impaired the enhanced fast velocity of APP anterograde transport. This phosphorylation of KLC1 increased in aged brains, suggesting deficient APP transport in neurons after aging., In neurons, amyloid β-protein precursor (APP) is transported by binding to kinesin-1, mediated by JNK-interacting protein 1b (JIP1b), which generates the enhanced fast velocity (EFV) and efficient high frequency (EHF) of APP anterograde transport. Previously, we showed that EFV requires conventional interaction between the JIP1b C-terminal region and the kinesin light chain 1 (KLC1) tetratricopeptide repeat, whereas EHF requires a novel interaction between the central region of JIP1b and the coiled-coil domain of KLC1. We found that phosphorylatable Thr466 of KLC1 regulates the conventional interaction with JIP1b. Substitution of Glu for Thr466 abolished this interaction and EFV, but did not impair the novel interaction responsible for EHF. Phosphorylation of KLC1 at Thr466 increased in aged brains, and JIP1 binding to kinesin-1 decreased, suggesting that APP transport is impaired by aging. We conclude that phosphorylation of KLC1 at Thr466 regulates the velocity of transport of APP by kinesin-1 by modulating its interaction with JIP1b.

The Intergovernmental Panel on Climate Change recommends keeping the increase in temperature to less than a two-degree increase by the end of the century, but the direct impact of global warming on ecosystems including microbes has not been investigated. Here we performed thermal adaptation of two species and three strains of mesophilic microbes for improvement of the survival upper limit of temperature, and the improvement was evaluated by a newly developed method. To understand the limitation and variation of thermal adaptation, experiments with mutators and by multiple cultures were performed. The results of experiments including genome sequencing and analysis of the characteristics of mutants suggest that these microbes bear a genomic potential to endure a 2-3°C rise in temperature but possess a limited variation of strategies for thermal adaptation.

Plant complex-type

For a sustainable society, we must consider how to reduce the CO2 emissions from buildings; however, the ventilation frequency in the toilet (i.e., bathroom or water closet) has not been changed in recent years. Only a few attempts have been made so far to reduce the ventilation frequency in toilets to save energy, despite their further technological developments. In this report, we considered evacuating the odor as soon as possible by providing an exhaust port at the bottom of the wall (hereinafter referred to as baseboard deodorization). We also considered the effect of baseboard deodorization for different toilet (bathroom) sizes. First, we surveyed the relationship between the odor detected by a sensor and a human’s olfactory sense and the ventilation volume with the toilet in operation to verify the usefulness of the sensors. Secondly, we analyzed the air environment using computational fluid dynamics (CFD). The results of the measurements and a questionnaire survey showed a certain degree of correlation between the indication of the degree of contamination in the air and the odor intensity. The results of the CFD analysis indicated that large-scale toilets could accumulate air more easily than small toilets; however, in either case, the ammonia concentration could be lowered by using baseboard deodorization. It was also found that the exhaust from baseboard deodorization greatly contributed to reducing the ammonia concentration.

In this study, we propose a ductless air conditioning system using the Coanda Effect for a medium size office building to achieve a net-zero energy building (ZEB). The indoor temperature environment and air flow characteristics during cooling and heating conditions created by this system were evaluated. In addition, to validate the computational fluid dynamics (CFD) analysis results when the heating system was activated, the results were compared with the measurement results. The investigation indicated that for cooling, a good thermal environment could be established in the residential area; however, local draught continued to be an issue. For heating, it was confirmed that heating of the residential area could be accomplished using floor suction. In addition, it was shown that the accuracy of the CFD analytical results can be improved by adjusting the input conditions to the actual conditions.

In recent years, energy conservation has become a major focus in the industrial sector. Many office buildings in Japan achieve energy savings by introducing highly efficient equipment and systems, such as high-temperature cooling water (14 °C), which increases heat source efficiency. However, such equipment requires adjustments to increase operational efficiency. In this case study, the efficiency of equipment using high-temperature cooling water was further improved through operation control optimization. The energy efficiency before and after the improvement was compared. The target building has chilled and hot water supplied to each floor from district heating and high-temperature chilled water supplied from cooling chillers on the rooftop. The energy consumption of two floors was evaluated: a subjective floor with equipment using high-temperature cooling water installed, and a common floor with a conventional system. After on-site verification, changes were made to the operation control of the cooling towers, condenser pumps, primary pumps, secondary pumps, and air handling units. As a result, the coefficient of performance of the water-cooled chiller and the whole system improved by 0.40 and 0.45, respectively. The flow rate of the air conditioning equipment using high-temperature cooling water decreased while maintaining an equivalent amount of heat extraction. In conclusion, the efficiency of the equipment was further improved by operation control optimization.

Nonfaceted growth of (111)-oriented epitaxial KBr crystals on sapphire single crystal substrates has been achieved using a novel vacuum deposition method of flux-mediated epitaxy, involving the use of ionic liquids as a flux. It was found that the ionic liquid could act as a flux to promote the growth of KBr at higher growth temperatures and to stabilize its unstable polar (111) face with no faceting of the crystal surface. Even after evaporation of the remaining ionic liquid to remove it from the KBr crystals, the atomically flat (111) surface could be preserved without refaceting.

The present study considers a fuzzy color system in which three membership functions are constructed on a color triangle. This system can process a fuzzy input to a color triangle system and output the center of gravity of three weights associated with respective grades. Three fuzzy sets (red, green, and blue) are applied to the color triangle relationship. By treating the attributes of redness, greenness, and blueness on the color triangle, a target color can be easily obtained as the center of gravity of the output fuzzy set. In the present paper, 0% triangle is consisted of the lines of 0% redness, 0% greenness, and 0% blueness of the attributes. The colors on 0% triangle map into the right corner of tone triangle (on C or near C). As compare the inference results for fuzzy inputs with those for crisp inputs, move to W (white region). The input-output relationship is shown by redness and chromaticness. The inference outputs for crisp inputs and for fuzzy inputs are obviously different. Those for crisp inputs show vertically linear.

The translational temperature and the flow velocity distributions in high enthalpy flows are deduced with Two-photon Absorption Laser induced fluorescence diagnostics system to atomic oxygen. The laser line width and the center excitation wavelength are estimated by LIF profiles obtained from a flow reactor simultaneously. In this flow reactor, atomic oxygen is generated by microwave discharge. The number density of atomic oxygen in this flow reactor is estimated by titration with nitrogen dioxide. Compared with the LIF signal from the flow reactor set inside the measurement region, the number density distributions in Arc heated wind tunnel flow are obtained. From these results, enthalpy modal fractions are evaluated.

Two-photon absorption laser induced fluorescence (TALIF) is applied to measure the recombination coefficient of atomic oxygen under several kPa pressure. The recombination coefficient of oxygen on the oxide SiC is estimated as 6.4×10(exp -3) at the total pressure of 2,240 Pa, the surface temperature of 1,150K. From this result, we confirm that the recombination coefficient has pressure dependency., 資料番号: PA1520004000