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Highly luminescent silver(I) coordination polymers [Ag2X2(PPh3)2(Me2pyz)]n(X = I, Br, Cl; Me2pyz: 2,5-dimethylpyrazine) were prepared together with copper congeners [Cu2X2(PPh3)2(Me2pyz)]n(X = I, Br). All the complexes showed thermally activated delayed fluorescence from the charge-transfer states in the visible region, from blue to red. The isomorphous relationship among the complexes allowed a detailed discussion of the effect of halogenido ligands and crystal packing on their luminescence energy. The relaxation in the emissive excited states (ESs) was determined to be more remarkable in silver complexes than in copper complexes despite their isomorphous structures, and the electronic effect of halogenido ligands was comparable to the effect of relaxation in emissive ESs.

ABSTRACT The demand for maintenance and repair of concrete structures in service has been critically increasing worldwide. A variety of techniques and evaluation methods for diagnosis and prognosis of the [...]

ABSTRACT The durability of concrete structures decreases easily due to such environmental effects. For effective maintenance of concrete structures, it is necessary to evaluate not only the values of mechanical [...]

Structural and thermodynamic transitions of artificially designed α-helical nanofibers were investigated using eight peptide variants, including four peptides with amide-modified carboxyl termini (CB peptides) and four unmodified peptides (CF peptides). Temperature-dependent circular dichroism spectroscopy and differential scanning calorimetry showed that CB peptides exhibit thermostability up to 50 °C higher than CF peptides. As a result, one of the denaturation temperatures approached nearly 130 °C, which is exceptionally high for a biomacromolecule. Thermodynamic analysis and microscopy observations also showed that CB peptides undergo a thermal transition similar to the phase transition in liquid crystals. In addition, one of the peptides showed a sharp and highly cooperative transition with a small enthalpy change at around 25 °C, which was ascribed to a giga-bundle burst of the molecular assembly. These macroscopic changes in the thermostability and crystallinity of CB peptides may be attributed to an increased amphiphilicity of the molecule in the direction of the helix axis, originating from the microscopic modification of the carboxyl-terminus.

ABSTRACT The elastic wave methods for non-destructive evaluation (NDE) in concrete are theoretically reviewed. These include basics of ultrasonic testing (UT), impact-echo (IE), and acoustic emission (AE). Starting with the [...]

The strength of hydrogen bonds in molecular crystals has been investigated through X-ray structural analysis and vibrational spectroscopy, and the interatomic distances and the stretching vibrational frequency involving hydrogen bonds have been known to exhibit a linear relationship. However, these studies are limited to relatively small molecular compounds, such as amino acids. In this study, we employed tetrapeptide as a model system to investigate the hydrogen bond network in the peptide crystal. Single crystal X-ray diffraction revealed that the peptide crystal structure had bifurcated hydrogen bonds. Raman spectroscopy exhibited that the vibrational frequency of amide bonds correlated linearly to their interatomic distance, but the rate of the change was significantly low compared with previous works. Fragment molecular orbital calculations also revealed that bifurcated hydrogen bonds affect the strength of the hydrogen bonds. This study provides a valuable model system for discussing the effects of bifurcated hydrogen bonds in various crystals of peptides.

ABSTRACT Steel-making slag concrete (SSC) is an environmental friendly material made mainly of by-products of steel industry without using Portland cement. The fatigue characteristics of SSC under compression in submerged [...]

ABSTRACT The Great East-Japan Earthquake hit Tohoku area in Japan on March 11, 2011. A large number of concrete structures were damaged due to the 9.0 magnitude earthquake of the [...]

ABSTRACT Investigation on fracture process zones in notched concrete beams under three-point bending is performed by applying acoustic emission (AE). The tests were conducted on beam specimens with different notch [...]

The Creutz–Taube ion, [(NH3)5RuII(μ-pz)RuIII(NH3)5]5+(pz = pyrazine) is a prominent example of multinuclear Ru systems, which exists in a mixed-valence state. Previous research efforts to interrogate the properties of this complex uncovered important knowledge regarding intramolecular charge transfer between strongly interacting metal centers. In this work, the Ru coordination with pyrazine was extended into two dimensions to create a [Ru(pz)2Cl2]n(Ru-pz) metal–organic framework (MOF). Both solvothermal and solvent-free synthetic methodologies were explored to optimize crystallinity and phase-purity. The detailed structural analysis using single-crystal and powder X-ray diffraction techniques, as well as X-ray absorption spectroscopy and total X-ray scattering confirmed the layered framework structure. In addition, an isostructural Os analogue could also be obtained. The spectroscopic and electrochemical properties of the resultant materials were assessed, which confirmed the existence of mixed-valence states and electronic delocalization between metal centers. This phenomenon facilitated electron propagation in solid-state with conductivity values of some samples reaching the semiconductor range of 10–7–10–4S/cm. These findings expand the well-established chemistry of discrete mixed-valent Ru complexes into the field of MOFs providing useful insights for further development of these systems.

ABSTRACT The impact-echo method is well-known as a nondestructive test for concrete structures. Methodologically, frequency spectra of elastic waves that are generated by a mechanical impact and propagate in concrete [...]

ABSTRACT Continuous acoustic emission (AE) monitoring is applied to a cyclic wet and dry test of reinforced concrete beams. The onset of corrosion and the nucleation of corrosion-induced cracks in [...]

ABSTRACT On-site measurement in concrete piers of a highway structure was conducted by visualized non-destructive testing (NDT). First, the radar technique was applied to identify delaminated areas between pre-stressed concrete [...]

ABSTRACT The impact-echo method has been widely applied to identification of defects in concrete. The presence and the location of the defect are estimated from identifying peak frequencies in the [...]

ABSTRACT Recently, a number of deterioration of reinforced concrete (RC) structures due to salt attack have been reported. After corrosion of reinforcing steel-bar (rebar) is nucleated, expansion of corrosion products [...]

ABSTRACT As a detailed inspection of a concrete structure in service, core samples are usually drilled out and then mechanical properties are measured. In this study, damage estimation of concrete [...]

ABSTRACT The fracture mode of cracking in concrete is normally changing from tensile mode to shear mode at impending failure. As for crack classification in concrete by acoustic emission (AE) [...]

Typical amorphous aerogels pose great potential for CO2adsorbents with high surface areas and facile diffusion, but they lack well-defined porosity and specific selectivity, inhibiting utilization of their full functionality. To assign well-defined porous structures to aerogels, a hierarchical metal–organic aerogel (HMOA) is designed, which consists of well-defined micropores (d∼ 1 nm) by coordinative integration with chromium(III) and organic ligands. Due to its hierarchical structure with intrinsically flexible coordination, the HMOA has excellent porous features of a high surface area and a reusable surface with appropriate binding energy for CO2adsorption. The HMOA features high CO2adsorption capacity, high CO2/N2IAST selectivity, and vacuum-induced surface regenerability (100% through 20 cycles). Further, the HMOA could be prepared via simple ambient drying methods while retaining the microporous network. This unique surface-tension-resistant micropore formation and flexible coordination systems of HMOA make it a potential candidate for a CO2adsorbent with industrial scalability and reproducibility.

In nature, chirality displays itself in diverse forms and on various hierarchical scales. Among the various types of chirality, supramolecular chirality is of particular interest due to its ability to amplify and induce chirality, which aids in understanding the fundamental principles of chirality transfer and is also suitable for chirality applications at the macroscopic scale. Herein, we report the synthesis of a novel chiral organic semiconductor 2,9-di(hexan-2-yl)anthra[2,1,9-def:6,5,10-d′e′f′]diisoquinoline-1,3,8,10 (2H, 9H)-tetraone (ClCPDI-C6) and its self-assembly into supramolecular nanowires (NWs). The chirality of the NWs was successfully transferred via intra- and inter-molecular interactions from the chiral pendant to the perylene diimide (PDI) core after self-assembly. Upon exposing the organic NWs to phenylhydrazine dopant vapor, the average mobility of the NW transistor was increased from 0.0085 to 0.026 cm2V–1s–1. Additionally, phenylhydrazine molecular doping of the NWs significantly enhanced their optical performance in comparison with the undoped NWs, with improved photoresponsivity (R) (∼3 times higher), photosensitivity (P) (∼10 times higher), external quantum efficiency (∼3 times higher), and detectivity (D*) (∼8 times higher). The detectivity of the phenylhydrazine-doped NWs was 1 or 2 orders of magnitude higher than that previously reported for chiral PDI NWs. Notably, they showed a fast and stable real-time photoswitching of both undoped and doped ClCPDI-C6 NWs (<90 ms), indicating a high sensitivity to visible light and great potential in photodetector and photoswitching applications. From density functional theory calculations, after absorbing phenylhydrazine on the ClCPDI-C6 NWs, the increased electron affinity contributes to increased optoelectronic performance. Our investigation paves the way for future in-depth studies on the relationship between the structure and supramolecular chirality with optoelectronic device performance.

In condensed matter, phase separation is strongly related to ferroelasticity, ferroelectricity, ferromagnetism, electron correlation, and crystallography. These ferroics are important for nano-electronic devices such as non-volatile memory. However, the quantitative information regarding the lattice (atomic) structure at the border of phase separation is unclear in many cases. Thus, to design electronic devices at the molecular level, a quantitative electron–lattice relationship must be established. Herein, we elucidated a PdII–PdIV/PdIII–PdIIIphase transition and phase separation mechanism for [Pd(cptn)2Br]Br2(cptn = 1R,2R-diaminocyclopentane), propagated through a hydrogen-bonding network. Although the Pd···Pd distance was used to determine the electronic state, the differences in the Pd···Pd distance and the optical gap between Mott–Hubbard (MH) and charge-density-wave (CDW) states were only 0.012 Å and 0.17 eV, respectively. The N–H···Br···H–N hydrogen-bonding network functioned as a jack, adjusting the structural difference dynamically, and allowing visible ferroelastic phase transition/separation in a fluctuating N2gas flow. Additionally, the effect of the phase separation on the spin susceptibility and electrical conductivity were clarified to represent the quasi-epitaxial crystals among CDW–MH states. These results indicate that the phase transitions and separations could be controlled via atomic and molecular level modifications, such as the addition of hydrogen bonding.

This investigator-initiated, phase 2, single-arm trial primarily assessed the efficacy of G47∆, a triple-mutated, third-generation oncolytic herpes simplex virus type 1, in 19 adult patients with residual or recurrent, supratentorial glioblastoma after radiation therapy and temozolomide (UMIN-CTR Clinical Trial Registry UMIN000015995). G47Δ was administered intratumorally and repeatedly for up to six doses. The primary endpoint of 1-yr survival rate after G47∆ initiation was 84.2% (95% confidence interval, 60.4–96.6; 16 of 19). The prespecified endpoint was met and the trial was terminated early. Regarding secondary endpoints, the median overall survival was 20.2 (16.8–23.6) months after G47∆ initiation and 28.8 (20.1–37.5) months from the initial surgery. The most common G47∆-related adverse event was fever (17 of 19) followed by vomiting, nausea, lymphocytopenia and leukopenia. On magnetic resonance imaging, enlargement of and contrast-enhancement clearing within the target lesion repeatedly occurred after each G47∆ administration, which was characteristic to this therapy. Thus, the best overall response in 2 yr was partial response in one patient and stable disease in 18 patients. Biopsies revealed increasing numbers of tumor-infiltrating CD4+/CD8+lymphocytes and persistent low numbers of Foxp3+cells. This study showed a survival benefit and good safety profile, which led to the approval of G47∆ as the first oncolytic virus product in Japan.

Abstract Failures in high-strength steel tendons of prestressed concrete structures are becoming a serious problem, as the deterioration of structures progresses due to aging. The failure is mainly attributed to [...]

Abstract Dynamic failure in fiber-reinforced concrete (FRC) slabs was studied experimentally and analytically. Due to blasting, damaged areas were created in the specimens, as the crater at the top surface [...]

Abstract A series of standard concrete beams with plastic P-T tendon ducts were tested at the University of Edinburgh using a range of NDT techniques including impact--echo (I-E), stack imaging [...]

Abstract The impact-echo method is well known as a non-destructive testing for concrete structures. Taking out resonant frequencies responsible for locations of reflectors in frequency spectra, locations of reflectors are [...]

Abstract For recycling concrete, the use of recycled aggregate has been extensively studied in Japan. It is widely recognized that compressive strength in concrete of recycled aggregate is lower than [...]

Abstract Corrosion of reinforcing steel in concrete is studied by using AC impedance. Subjected to different conditions and chloride concentrations, a laboratory study was conducted to estimate the corrosion rate [...]

Abstract The impact-echo technique is a nondestructive evaluation for defects in concrete structures by analyzing elastic waves due to a mechanical impact. In order to improve the technique, a new [...]

Abstract In recent years, deterioration of concrete structures has been widespread and become a social problem. Because the durability of concrete structures decreases easily due to such external effects, as [...]

Non-destructive evaluation techniques by the half-cell potential measurement are applied to estimate the corrosion of reinforcing steel-bars in concrete slabs under cyclic wet and dry conditions. The three-dimensional boundary element [...]

Abstract Nucleation of corrosion cracking is analyzed by acoustic emission-simplified Green's functions for moment tensor analysis, by which crack kinematics of locations, types and orientations are quantitatively determined. These kinematical [...]

The 1H-2-benzopyran-5,8-dione structure was synthesized by a cascade reaction through Michael addition, elimination of HBr, and O-alkylation between a dibromobenzoquinone derivative and β-ketoesters under basic conditions. The reaction using potassium carbonate and 18-crown-6 in THF was the best condition, giving 1H-2-benzopyran-5,8-dione derivatives in good yields. The UV-vis absorption spectrum and cyclic voltammogram of the synthesized 1H-2-benzopyran-5,8-dione derivative were measured, clarifying the photophysical and redox properties.1H-2-Benzopyran-5,8-dione skeleton was found to be selectively synthesized through a cascade reaction of Michael addition, elimination of HBr, and O-alkylation between a dibromobenzoquinone derivative and β-ketoesters. The photophysical and redox properties of the synthesized 1H-2-benzopyran-5,8-dione with red color were also elucidated.

Lung cancer is one of the most aggressive tumour types. Targeted therapies stratified by oncogenic drivers have substantially improved therapeutic outcomes in patients with non-small-cell lung cancer (NSCLC)1. However, such oncogenic drivers are not found in 25–40% of cases of lung adenocarcinoma, the most common histological subtype of NSCLC2. Here we identify a novel fusion transcript of CLIP1and LTKusing whole-transcriptome sequencing in a multi-institutional genome screening platform (LC-SCRUM-Asia, UMIN000036871). The CLIP1–LTKfusion was present in 0.4% of NSCLCs and was mutually exclusive with other known oncogenic drivers. We show that kinase activity of the CLIP1–LTK fusion protein is constitutively activated and has transformation potential. Treatment of Ba/F3 cells expressing CLIP1–LTK with lorlatinib, an ALK inhibitor, inhibited CLIP1–LTK kinase activity, suppressed proliferation and induced apoptosis. One patient with NSCLC harbouring the CLIP1–LTKfusion showed a good clinical response to lorlatinib treatment. To our knowledge, this is the first description of LTKalterations with oncogenic activity in cancers. These results identify the CLIP1–LTKfusion as a target in NSCLC that could be treated with lorlatinib.

A tridentate 3-pyridyl-based ligand containing a hexaazaphenalene skeleton (3-TPHAP–) with topologically isolated p orbitals was prepared by a one-pot reaction. It was successfully reacted with a Co2+salt and a 1,4-benzenedicarboxylic acid co-ligand to give a porous coordination network. In the structure, the hexaazaphenalene skeleton interacts with water to form an internal hydrogen bonding network, allowing the entire pore space to be revealed by single-crystal X-ray diffraction (SXRD). The network structure consists of dimeric Co clusters featuring labile sites occupied by solvent molecules. Several guest molecules, namely, anthracene, triphenylene, and iodine, were incorporated inside the network. The resultant encapsulated structures were elucidated by SXRD, revealing unusual host–guest interactions with a subtle structural modulation.

Purpose: This study investigated pre-evacuation times and evacuation behaviors of vulnerable people during the 2018 flooding in Shimobara, Okayama, Japan, and the flood-triggered factory explosion, a natural hazard-triggered technological accident known as a natural-hazard-triggered technological accidents (Natech). This study examined factors that affected evacuation decisions and pre-evacuation time, estimated the evacuation time in case of no explosion and identified community disaster prevention organization response efforts for vulnerable people. Design/methodology/approach: Interviews with all 18 vulnerable people who experienced the event were conducted. Multiple regression analysis was used to examine the effect of six factors on evacuation time and reasons for delayed evacuation. Findings: Factors affecting evacuation decisions included the sound of the explosion, followed by recommendations from relatives and the community disaster prevention organization. Explosion-related injuries delayed early evacuation, but experience of previous disasters and damage had a positive effect on early evacuation. The explosion sound accelerated evacuation of non-injured people; however, explosion-related injuries significantly delayed evacuation of injured individuals. The Shimobara community disaster prevention organization’s disaster response included a vulnerable people registry, visits to all local households and a multilayered approach that enabled monitoring of all households. Originality/value: This is the first study to examine the evacuation behavior of vulnerable people and community responses during a Natech event.

Background. Mutations in the K-ras oncogene at codon 12 are detected at a remarkably high frequency in pancreatic carcinomas and are believed to be a critical event in oncogenesis. The authors attempted to detect Kras mutations in DNA obtained from pure pancreatic juice collected endoscopically, as a novel diagnostic approach to pancreatic carcinoma. Methods. K-ras mutations were examined using the two-step polymerase chain reaction (PCR) combined with restriction enzyme digestion, followed by nonradioisotopic single-strand conformation polymorphism (SSCP) analysis. Results. Specific mutations of the K-rus gene at codon 12 were found in six of nine (67%) duct cell carcinomas, all of which were negative by cytodiagnosis of the same pure pancreatic juice. K-ras mutations were not detected in the pancreatic juice from 14 healthy control subjects, 10 patients with chronic pancreatitis, or 3 patients with islet cell tumors. Conclusions. Detection of K-ras mutation at codon 12 in pancreatic juice is highly specific for diagnosing pancreatic duct cell carcinoma and may be a valuable diagnostic modality for pancreatic carcinoma and for differentiating chronic pancreatitis from carcinoma. Cancer 1994; 73:1589-94. Key words: K-ras oncogene, pancreatic carcinoma, endoscopic retrograde pancreatography, pancreatic juice, single-strand conformation polymorphism, polymerase chain reaction.

Generally, volatile thiols are hard to be measured with electrospray-ionization-type LC-MS due to the volatility. Therefore, we here evaluated the pretreatment of their S-bimanyl derivatization by monobromobimane to enable the detection as nonvolatile derivative. Consequently, we successfully developed the convenient and efficient method through the quantitative analysis of 2-furanmethanethiol (volatile thiol odorant of coffee aroma) in coffee bean.