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We report Cu, Fe, N‐doped carbon nanotubes, (Cu,Fe)−N−CNT, as electrocatalysts for the oxygen reduction reaction (ORR) in acidic media. (Cu,Fe)−N−CNT was prepared using a silica coating method in pyrolysis to minimize the formation of carbon‐coated metal oxide or carbide nanoparticles, which are known to be inactive for the H2O2 reduction. (Cu,Fe)−N−CNT shows a turnover frequency of 0.66 e− site−1 s−1 at +0.8 V vs. RHE and H2O2 yields of <1 % for the ORR with a utilization factor of active sites of 82 %. Kinetic analysis reveals that 4e− transfer rates for (Cu,Fe)−N−CNT are higher than those of a monometallic counterpart of Fe−N−CNT. In situ X‐ray absorption spectroscopy enables us to determine redox potentials: E°'(FeIII/FeII)=0.65 V vs. RHE and E°'(CuII/CuI)=0.45 V for (Cu,Fe)−N−CNT, and E°'(FeIII/FeII)=0.65 V for Fe−N−CNT. These results indicate that bimetallic doping into carbon nanotubes gives the effect on kinetic parameters but not on thermodynamic ones. In other words, there is no direct electronic interactions between the Cu and Fe active sites for (Cu,Fe)‐N‐CNT because such interactions should modulate their redox potentials. [ABSTRACT FROM AUTHOR]

Recently, biomolecular condensates formed through liquid–liquid phase separation have been widely reported to regulate key intracellular processes involved in cell biology and pathogenesis. BRD4 is a nuclear protein instrumental to the establishment of phase-separated super-enhancers (SEs) to direct the transcription of important genes. We previously observed that protein droplets of BRD4 became hydrophobic as their size increase, implying an ability of SEs to limit the ionization of water molecules by irradiation. Here, we aim to establish if SEs confer radiation resistance in cancer cells. We established an in vitro DNA damage assay that measures the effect of radicals provoked by the Fenton reaction on DNA integrity. This revealed that DNA damage was markedly reduced when BRD4 underwent phase separation with DNA. Accordingly, co-focal imaging analyses revealed that SE foci and DNA damage foci are mutually exclusive in irradiated cells. Lastly, we observed that the radioresistance of cancer cells was significantly reduced when irradiation was combined with ARV-771, a BRD4 de-stabilizer. Our data revealed the existence of innately radioresistant genomic regions driven by phase separation in cancer cells. The disruption of these phase-separated components enfolding genomic DNA may represent a novel strategy to augment the effects of radiotherapy. [ABSTRACT FROM AUTHOR]

We previously developed a simplified finite element (FE) "unit" model to reproduce the mechanical interaction between the smooth muscle layer and elastic lamina (EL) in the aortic media. Nevertheless, whether this simplified FE model can represent the structure of a real medial wall and whether its modeling technique can help in developing a highly sophisticated and structure-based aortic FE model should be determined. Therefore, this study aimed to computationally represent EL buckling in the aortic medial ring at an unloaded state based on the integrated unit models and reproduce transmural variations in EL waviness across the vascular wall. We confirmed that the inner and outer layers of the medial wall were relatively subjected to compressive and tensile residual stresses, respectively, at the unloaded state, implying that the ring model will open spontaneously when it is radially cut. In addition, the residual stresses computed under such a stress-free condition were comparable to the analytically estimated values, partially supporting the validity of our modeling approach. Although further study is still required, the information obtained in this study will greatly improve the understanding of basic aortic physiology and pathophysiology and provide a basis for performing more sophisticated computational modeling of the aortic wall. [ABSTRACT FROM AUTHOR]

In pursuing Japan's target of net zero greenhouse gas (GHG) emissions by 2050, decarbonization strategies at the regional level have been taking place nationally. Some successes have been achieved in the residential sector in achieving decarbonization at the regional level due to improvements in the advancement of energy-saving technologies. An important prerequisite to achieving further decarbonization in the residential sector is understanding household electricity consumption of power demand objects. This study constructed a method for predicting residential electricity consumption in a case study region. First, we set up six models of household composition for scenario exercises. Then, we used the residential energy estimation based on daily activities (REEDA) method to calculate the hourly electricity consumption of each household composition in the four seasons based on the duration of daily life activity. Finally, we separately explore the impact of housing performance (insulation, airtightness), air-conditioning patterns (intermittent operation method in a habitable room/continuous operation method in a habitable room/continuous operation method in all rooms), and geographical location on residential air conditional electricity consumption. The output is a regional residential energy estimate method that can consider multiple key variables. We verified the developed model by (1) comparing the estimated output with the Japan Energy Database and (2) testing the method for various residential areas in Japan. The results showed an accuracy level greater than 75% and nationwide applicability. [ABSTRACT FROM AUTHOR]

Bacteria regulate virulence by using two‐component systems (TCSs) composed of a histidine kinase (HK) and a response regulator (RR). TCSs respond to environmental signals and change gene‐expression levels. The HK QseE and the RR QseF regulate the virulence of Enterobacteriaceae bacteria such as enterohemorrhagic Escherichia coli. The operon encoding QseE/QseF also contains a gene encoding an outer membrane lipoprotein, qseG. The protein product QseG interacts with QseE in the periplasmic space to control the activity of QseE and constitutes a unique QseE/F/G three‐component system. However, the structural bases of their functions are unknown. Here, crystal structures of the periplasmic regions of QseE and QseG were determined with the help of AlphaFold models. The periplasmic region of QseE has a helix‐bundle structure as found in some HKs. The QseG structure is composed of an N‐terminal globular domain and a long C‐terminal helix forming a coiled‐coil‐like structure that contributes to dimerization. Comparison of QseG structures obtained from several crystallization conditions shows that QseG has structural polymorphisms at the C‐terminus of the coiled‐coil structure, indicating that the C‐terminus is flexible. The C‐terminal flexibility is derived from conserved hydrophilic residues that reduce the hydrophobic interaction at the coiled‐coil interface. Electrostatic surface analysis suggests that the C‐terminal coiled‐coil region can interact with QseE. The observed structural fluctuation of the C‐terminus of QseG is probably important for interaction with QseE. [ABSTRACT FROM AUTHOR]

Furanopyrimidine (FPy) and 2,6-diamino-3-deazapurine (DC3Pu) nucleosides with the ability to interact in DDD and AAA H-bonding patterns, respectively, were prepared. The N-1 pKa value of the DC3Pu nucleoside was estimated to be 6.4, which is due to the lack of a nitrogen atom at the 3-position, suggesting that DC3Pu acts as a base interacting in a DDD H-bonding pattern under near physiological conditions. As DC3Pu and FPy are expected to form a thermally stable DDD:AAA type of base pair in an oligodeoxynucleotide (ODN) duplex, they were incorporated into ODNs, and the Tm value of the ODN duplex was determined. However, the ODN duplex containing a DC3Pu:FPy pair has a lower thermal stability than that containing a G:C pair does, although its thermal stability is equal to that of an ODN duplex with an A:T pair even under acidic conditions. [ABSTRACT FROM AUTHOR]

The introduction of nanofillers into conventional microsized fiber-reinforced plastic composites has great potential to improve the fracture toughness and crystalline properties of composites, especially for semicrystalline thermoplastic polymers. Although the selective reinforcement is possible by nanofiller addition, the influence of the addition position of nanofillers on the mechanical properties and crystalline properties still has not been revealed. In this work, the cellulose nanofibers (CNFs) as the secondary filler were added (i) into a polypropylene (PP) matrix by a melt-mixing process and (ii) onto a carbon fiber (CF) surface by a dip-coating process in a CF-reinforced PP composite. By focusing on the transcrystals surrounding CFs, which enable improvement of the interfacial strength, the crystalline properties and mechanical properties were investigated through polarized optical microscopy, differential scanning calorimetry, X-ray diffraction, and 3-point bending tests in this study. We revealed that (i) CNF addition into the PP matrix disturbed the transcrystallization surrounding CFs and that the mechanical properties slightly decreased. Conversely, (ii) CNF addition onto the CF surface promoted transcrystallization surrounding the CF, and the flexural yield strength and modulus significantly improved by a maximum of 30% and 63%, respectively. [ABSTRACT FROM AUTHOR]

This study aimed to improve the dispersion state of single‐walled carbon nanotubes (SWCNTs) in a cyclo‐olefin polymer (COP) matrix by introducing extensional flow during the compounding through a twin‐screw extruder (TSE). A modified mixing element with multiple holes, called a fixed blister disc (XBD), was developed. To describe the mixing performance of XBD, the flow state was characterized via numerical simulation and acquisition of process data such as pressure drop (∆P) at XBD and specific mechanical energy (SME), while the operational conditions of TSE were varied. The dispersion state of SWCNTs was evaluated from the viewpoint of the melt viscoelastic property, surface resistivity of extruded samples and mechanical properties of injection molded samples. Furthermore, the dispersion morphology was observed via optical microscopy and scanning electron microscopy. As a result, the mixing performance of XBD was improved by increasing the ratio of throughputs Q to screw speed Ns (Q/Ns) since ∆P, which is related to extensional stress, was increased. However, the trade‐off relationship between ∆P and SME was confirmed versus Q/Ns. Although the dispersion state at the submicron level was markedly improved with higher SME inputs, higher ∆P reduced the largest agglomerate size and improved dispersion uniformity. Consequently, the mechanical properties were improved significantly. [ABSTRACT FROM AUTHOR]

Fe/N/C single‐atom catalysts containing Fe−Nx sites prepared by pyrolysis are promising cathode materials for fuel cells and metal‐air batteries due to their high oxygen reduction reaction (ORR) activities. We have developed iron complexes containing N2‐ or N3‐chelating coordination structures with preorganized aromatic rings in a 1,12‐diazatriphenylene framework tethering bromo substituents as precursors to precisely construct Fe−N4 sites in an Fe/N/C catalyst. One‐step pyrolysis of the iron complex with carbon black forms atomically dispersed Fe−N4 sites without iron aggregates. X‐ray absorption spectroscopy (XAS) and electrochemical measurements revealed that the iron complex with N3‐coordination is more effectively converted to Fe−N4 sites catalyzing ORR with a TOF value of 0.21 e site−1 s−1 at 0.8 V vs. RHE. This indicates that the formation of Fe−N4 sites is controlled by precise tuning of the chemical structure of the iron complex precursor. [ABSTRACT FROM AUTHOR]

This study focused on realizing fire retardancy for polymer composites by using a cellulosic biofiller and ammonium polyphosphate (APP). The motivation of this study was based on revealing the mechanism of the synergetic effect of a cellulosic biofiller and APP and determining the parameters required for achieving a V-0 rating in UL94 standard regardless of the kind of polymer system used. As for the polymer matrix, polypropylene and polylactic acid were used. The flammability, burning behavior and thermal decomposition behavior of the composites were investigated through a burning test according to the UL-94 standard, cone calorimetric test and thermogravimetric analysis. As a result, the incorporation of a high amount of cellulose enabled a V-0 rating to be achieved with only a small amount of APP despite the variation of the optimum cellulose loading between the matrix polymers. Through analysis, the results indicated that APP decreased the dehydration temperature of cellulose. Furthermore, APP promoted the generation of enough water as a nonflammable gas and formed enough char until the degradation of the polymer matrix was complete. The conditions required to achieve the V-0 rating were suggested against composites incorporating APP and biofillers. Furthermore, the suggested conditions were validated by using polyoxymethylene as a highly flammable polymer. [ABSTRACT FROM AUTHOR]

According to the Grotthuss–Draper law, light must be absorbed by a substrate to initiate a photoreaction. There have been several reports, however, on the promotion of photoreactions using hypervalent iodine during irradiation with light from a non‐absorbing region. This contradiction gave rise to a mystery regarding photoreactions involving hypervalent iodine. We demonstrated that the photoactivation of hypervalent iodine with light from the apparently non‐absorbing region proceeds via a direct S0→Tn transition, which has been considered a forbidden process. Spectroscopic, computational, and synthetic experimental results support this conclusion. Moreover, the photoactivation mode could be extended to monovalent iodine and bromine, as well as bismuth(III)‐containing molecules, providing new possibilities for studying photoreactions that involve heavy‐atom‐containing molecules. [ABSTRACT FROM AUTHOR]

According to the Grotthuss–Draper law, light must be absorbed by a substrate to initiate a photoreaction. There have been several reports, however, on the promotion of photoreactions using hypervalent iodine during irradiation with light from a non‐absorbing region. This contradiction gave rise to a mystery regarding photoreactions involving hypervalent iodine. We demonstrated that the photoactivation of hypervalent iodine with light from the apparently non‐absorbing region proceeds via a direct S0→Tn transition, which has been considered a forbidden process. Spectroscopic, computational, and synthetic experimental results support this conclusion. Moreover, the photoactivation mode could be extended to monovalent iodine and bromine, as well as bismuth(III)‐containing molecules, providing new possibilities for studying photoreactions that involve heavy‐atom‐containing molecules. [ABSTRACT FROM AUTHOR]

Hybrid thermoplastic composites are getting attention in light weight applications. The manufacturing process of hybrid composites is that discontinuous fiber-reinforced thermoplastics are injected onto the textile-reinforced thermoplastics through injection over-molding. The key topic of this process is to achieve a reliable interfacial bonding strength, which has a strong dependence on the molding conditions. As a novel approach, we adopted a carbon nanotube-based thermoplastic film to make nanoscale interconnections between different layers by inserting films between the layers. In this work, the following influences were investigated with respect to the interlaminar shear strength by short beam shear test: the (i) existence, (ii) dispersion state, (iii) concentration of carbon nanotubes, and (iv) injection over-molding conditions. Furthermore, the delaminated surface after short beam shear test was assessed via SEM observation. Consequently, polypropylene-injected hybrid composite with 1 wt% carbon nanotubes exhibited a 52% increase in interlaminar shear strength compared with the specimen without carbon nanotubes. Additionally, the combination of short carbon fibers, which were filled in injected polypropylene, and carbon nanotubes drastically enhanced the interlaminar shear strength. The optimization of carbon nanotube dispersion and molding condition provides strong improvement of interlaminar shear strength. However, excessive addition of carbon nanotube deteriorates the interlaminar shear strength. [ABSTRACT FROM AUTHOR]

Abstract: Non‐precious metal electrocatalysts are under investigation as alternatives to platinum‐group metal electrocatalysts for the oxygen reduction reaction (ORR), which is required for cathode materials in fuel cells. Herein, we describe a new method for the synthesis of metal and nitrogen‐containing carbon (M/N/C) catalysts with high ORR activity using π‐expanded Fe(Salen) precursors. The Fe/N/C ORR catalysts were obtained by pyrolysis of a mixture of carbon support (Vulcan XC‐72R) and the iron complex precursors. The Fe/N/C catalyst prepared from N,N'‐bis(2‐hydroxy‐1‐naphthylidene)‐1,2‐phenylenediamino‐iron(III) chloride has an onset potential of 860 mV, which is positively shifted by 60 mV from that of the catalyst prepared from the simple Fe(Salen) complex. The catalyst promotes efficient four‐electron reduction in the ORR. XAFS and XPS studies reveal that the Fe/N/C catalysts have atomically‐dispersed iron active sites and that the activity depends on the high content of pyridinic nitrogen. This new methodology facilitates the design of non‐precious metal‐carbon catalysts with excellent ORR activity. [ABSTRACT FROM AUTHOR]

Nuclear pore complexes (NPCs) are the central apparatus of nucleocytoplasmic transport. Disease-specific alterations of NPCs contribute to the pathogenesis of many cancers; however, the roles of NPCs in glioblastoma (GBM) are unknown. In this study, we report genomic amplification of NUP107, a component of NPCs, in GBM and show that NUP107 is overexpressed simultaneously with MDM2, a critical E3 ligase that mediates p53 degradation. Depletion of NUP107 inhibits the growth of GBM cell lines through p53 protein stabilization. Mechanistically, NPCs establish a p53 degradation platform via an export pathway coupled with 26S proteasome tethering. NUP107 is the keystone for NPC assembly; the loss of NUP107 affects the integrity of the NPC structure, and thus the proportion of 26S proteasome in the vicinity of nuclear pores significantly decreases. Together, our findings establish roles of NPCs in transport surveillance and provide insights into p53 inactivation in GBM. [Display omitted] • NUP107 overexpression inactivates p53 to promote tumorigenesis in WT-p53 GBM cell lines • Proteasome-tethered NPCs mediate p53 degradation in the nucleus in GBM • Transport surveillance by NPCs determines p53 fate in WT-p53 GBM cell lines Ikliptikawati et al. show that overexpression of NUP107 ensures p53 degradation by XPO1-mediated targeting of p53 to NPCs tethering 26S proteasomes in WT-p53 GBM cell lines. The NPC serves as transport surveillance for p53 degradation to promote tumorigenesis in GBM. [ABSTRACT FROM AUTHOR]

Cortical microcircuits are nonrandomly wired by neurons. As a natural consequence, spikes emitted by microcircuits are also nonrandomly patterned in time and space. One of the prominent spike organizations is a repetition of fixed patterns of spike series across multiple neurons. However, several questions remain unsolved, including how precisely spike sequences repeat, how the sequences are spatially organized, how many neurons participate in sequences, and how different sequences are functionally linked. To address these questions, we monitored spontaneous spikes of hippocampal CA3 neurons ex vivo using a high-speed functional multineuron calcium imaging (fMCI) technique that allowed us to monitor spikes with millisecond resolution and to record the location of spiking and non-spiking neurons. Multineuronal spike sequences (MSSs) were overrepresented in spontaneous activity compared to the statistical chance level. Approximately 75% of neurons participated in at least one sequence during our observation period. The participants were sparsely dispersed and did not show specific spatial organization. The number of sequences relative to the chance level decreased when larger time frames were used to detect sequences. Thus, sequences were precise at the millisecond level. Sequences often shared common spikes with other sequences; parts of sequences were subsequently relayed by following sequences, generating complex chains of multiple sequences. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa and Serratia marcescens can cause refractory keratitis resulting in corneal perforation and blindness. These bacteria produce various kinds of proteases. In addition to pseudomonal elastase (LasB) and alkaline protease, LasA protease and protease IV have recently been found to be more important virulence factors of P. aeruginosa . S. marcescens produces a cysteine protease in addition to metalloproteases. These bacterial proteases have a number of biological activities, such as degradation of tissue constituents and host defense-oriented proteins, as well as activation of zymogens (Hageman factor, prekallikrein and pro-matrix metalloproteinases) through limited proteolysis. In this article, the properties of these bacterial proteases are reviewed and the pathogenic roles of these proteases in pseudomonal keratitis are discussed. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented on the case of a man suffering from gelatinous droplike corneal dystrophy.

⊎ Background: Chicken egg white ovomacroglobulin (ovoM) is a potent protease inhibitor with broad-spectrum activity against various proteases. The combined effects of ovoM and the new quinolone, ofloxacin (OFLX) on experimental Pseudomonas aeruginosa keratitis were investigated. ⊎ Methods: The in vitro inhibitory effects of ovoM on protease activity in culture fluid of clinically isolated P. aeruginosa and on activity of human neutrophil elastase and cathepsin G were assayed using azo-casein as substrate. Albino rabbits received intrastromal injection of the isolated Pseudomonas strain (1 × 10 colony-forming units). At 16 h after inoculation, three treatment groups -0.1% ovoM alone, 0.3% OFLX alone, and a combination of both -and a non-treatment control group were tested. ⊎ Results: Protease activity in the culture solution and human neutrophil elastase was inhibited by ovoM, whereas cathepsin G was not inhibited effectively. In vivo additive therapeutic effects of ovoM and OFLX were observed at 96 h ( P < 0.05 compared with OFLX alone). ⊎ Conclusion: The results indicate that inhibition of proteolytic activity with ovoM is useful in preventing stromal degradation in P. aeruginosa keratitis. [ABSTRACT FROM AUTHOR]

In order to identify the causative factors of ring abscess, which is the characteristic feature of pseudomonal keratitis, pseudomonal endotoxin, exotoxin A, and elastase were each separately injected into guinea pig cornea. There was no formation of ring abscess. Injection of living Pseudomonas aeruginosa strains IFO3455 and Takamatsu which produce all three molecules, clearly induced ring abscess. In contrast, when heat-killed bacteria strain IFO3455 or living bacteria of the non-elastase-producing strain PA103 were injected, ring abscess was not induced. Furthermore, when living bacteria strain IFO3455 were injected with anti-elastase antibody or a protease inhibitor, ovomacroglobulin, ring abscess formation was significantly inhibited. Histological examination demonstrated that the ring abscess was a dense accumulation and aggregation of polymorphonuclear leukocytes (PMN) with debris of cells and lamellae in the deep stroma at the corneal margins, suggesting prevention of PMN migration to the central lesion. The presence of anti-elastase antibody or a specific elastase inhibitor facilitated PMN migration towards living bacteria strain IFO3455 in an in vitro model. These results indicate that pseudomonal elastase is a necessary but not sufficient factor in the formation of ring abscess in pseudomonal keratitis. [ABSTRACT FROM AUTHOR]

We studied the inhibitory effects of chicken egg-white ovomacroglobulin (ovoM) on keratitis induced by 56000-Da protease (56 KP) of Serratia marcescens and by elastase (PE) and alkaline protease (PAP) of Pseudomonas aeruginosa. The effects of ovoM on the serratial and pseudomonal keratitis in rabbits were also elucidated. In one model, four drops of 56 KP, PE, or PAP (1 mg/ml) were applied to wounded corneas of eight eyes. Thereafter, 80 μl ovoM (10 mg/ml) was dropped into four eyes and 0.01 M phosphate-buffed 0.15 M saline (pH 7.4) into the other eyes as a control. The other in vivo test system involved intrastromal injection of S. marcescens or P. aeruginosa, by which each sample (10-10 colony-forming units) mixed with ovoM was injected into one cornea and the other cornea received organisms without ovoM. OvoM completely inhibited the activity of these bacterial proteases in vitro and reduced corneal destruction in experimental keratitis in rabbits. In addition, greatly accelerated wound healing was observed. [ABSTRACT FROM AUTHOR]

Hypervalent iodines are widely used in organic chemistry, and their most important feature is the three‐center four‐electron bond. However, there have been few reports on the measurement of their bond dissociation enthalpy (BDE). Therefore, in many cases, BDE is estimated by computational calculations. However, the value of a calculated BDE usually varies depending on the choice of functional and basis set, and the best method for making an accurate evaluation of the three‐center four‐electron bond has not been determined. We succeeded in determining the best functional and basis set to calculate the three‐center four‐electron bond to within 0.79% error and 0.53 standard deviation. Using the optimal functional and basis set, the first and second BDEs of several hypervalent iodines are calculated, and as the effect of benzene substituents was investigated, negative correlation was observed in the Hammett plot. In addition, the effect of ortho‐substituent in cyclic hypervalent iodine was found to be significant. Furthermore, the decomposition route of hypervalent iodine is calculated. The value of a calculated BDE usually varies depending on the choice of functional and basis set. We succeeded in determining the best functional and basis sets to calculate the three‐center four‐electron bond of hypervalent iodine to within 0.79% error and 0.53 standard deviation. Using the optimal functional and basis sets, the first and second BDEs of several hypervalent iodines are calculated, and additionally, the decomposition route of hypervalent iodine is calculated. [ABSTRACT FROM AUTHOR]

Abstract: The front cover artwork for issue 4/2018 represents research conducted in a collaboration between Osaka University (Japan) and Nippon Shokubai Co., Ltd. (Japan). The image illustrates the preparation of the Fe/N/C catalysts by pyrolysis of π‐expanded Fe(Salen) precursors for the oxygen reduction reaction. See the Full Paper itself at https://doi.org/10.1002/cctc.201701629. [ABSTRACT FROM AUTHOR]