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Circularly polarized luminescence (CPL) activity was induced on a racemic Tb complex with a 1,4,7-triazacyclononane-based tris-phenoxide ligand by the coordination of a chiral 1-phenylethylamine ligand to the Tb centre. tert-Butyl groups at the ortho-position of the phenoxide moieties were found to be important for efficient CPL induction in the Tb complex. [ABSTRACT FROM AUTHOR] more...

To elucidate the seroprevalence and rate of asymptomatic infection with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in Japanese children, serological analysis was performed using serum samples collected from March 2020 to February 2023. A total of 1493 serum samples were collected during the first study period (March 2020 to February 2021). None of the serum samples was positive for SARS‐CoV‐2 antibody. In the second period (March 2021 to February 2022), seven of the 1055 patients (0.7%) experienced SARS‐CoV‐2 infection. The third period (March 2022 to February 2023) was divided into three terms: from March to June 30, 2022; from July to October 2022; and from November 2022 to February 2023. The seroprevalence gradually increased throughout this period, with rates of 6.0%, 18.6%, and 30.4% in the three terms, respectively. Pediatric cases of asymptomatic SARS‐CoV‐2 infection occurred after the surge of Omicron variants. Since none of the SARS‐CoV‐2 antibody‐positive patients had a previous history of coronavirus disease 2019, the seroprevalence rate in this study may represent the rate of asymptomatic infection. [ABSTRACT FROM AUTHOR] more...

We present an Ir complex that extracts electrons from H2 at room temperature and stores them as a H2-derived energy carrier (H2EC) at room temperature. Furthermore, we demonstrate that this complex reduces CO2 to a metal–CO22− species at room temperature, and present the first electrospray ionisation mass spectrum for this compound. [ABSTRACT FROM AUTHOR] more...

Chemists have long sought to regulate the reactivity of H2, to yield hydride ions, hydrogen atoms, or electrons on demand. One source of inspiration for achieving this control is [NiFe]hydrogenase ([NiFe]H2ase), which reacts with H2 to form various hydrogen active species such as NiIII hydride species, NiII hydride species, and NiI low‐valent species. Chemists have attempted to synthesize these hydrogen active species not only as models for the active species of [NiFe]H2ase, but also as electron transfer catalysts. However, the synthesis of NiI complex directly from H2 has not been reported. This paper reports the first example of a single‐step synthesis of a NiI complex, via reaction of a NiII complex with H2, stable for over 3 months at room temperature and we further demonstrate a reductive coupling of acridinium ions as part of a reaction cycle. [ABSTRACT FROM AUTHOR] more...

The crystalline-state photochromism of a new organorhodium dinuclear complex having n-methoxypropyltetramethylcyclopentadienyl (η5-C5Me4</subscript>n-C3H6OCH3) and photoresponsive dithionite (μ-O2SSO2) ligands was investigated directly by performing single-crystal X-ray diffraction experiments; a reversible conformational change of the n-methoxypropyl moiety was intriguingly observed during the course of a thermal back-reaction. [ABSTRACT FROM AUTHOR] more...

This paper reports the first example of C−H arylation of benzene under mild conditions, using H2 as an electron source {turnover numbers (TONs)=0.7–2.0 for 24 h}. The reaction depends on a Rh‐based electron storage catalyst, and proceeds at room temperature and in aqueous solution. Furthermore, the H2 is inactive during the radical transfer step, greatly reducing unwanted side reactions. [ABSTRACT FROM AUTHOR] more...

Purpose: A zygomatic implant can be an effective device for rehabilitation of the severely resorbed maxilla. If zygomatic implants are used, onlay bone grafting or sinus augmentation would likely not be necessary. Where an anterior onlay bone graft is required, extension of the graft in the posterior region could be reduced. The results of the application of zygomatic implants in 9 patients and clinical evaluation of this therapy are reported. Materials and Methods: Nine patients received a total of 15 zygomatic implants. Six to 8 months elapsed for healing before second-stage surgery was performed. Six months after prosthetic treatment, patients' opinions were solicited by means of a questionnaire. Results: No implant was removed at the time of abutment connection surgery or during the follow-up period. In many cases, the zygomatic implant platform was located palatal to the alveolar ridge. However, no patients complained of any continuing speech impediment following superstructure fabrication. Computed tomograms taken before implant placement and 6 months after implant placement showed no sign of sinusitis in any patient. Discussion: The zygomatic implant allows shorter treatment time and hospitalization. However, there can be some problems in the application of zygomatic implants. Conclusion: It is necessary to investigate long-term clinical prognosis. [ABSTRACT FROM AUTHOR] more...

Spontaneous alveolar ridge growth in the posterior region of the mandible following placement of endosseous implants is reported. The study included 27 patients with totally edentulous mandibles and fixed prostheses supported by osseointegrated implants placed between the mental foramina. In 5 patients, an increase in the height of the alveolar crest was observed in the molar region; the increase ranged from 3.3% to 8.6%. This osseous proliferation may be a physiologic response to stress distribution in the molar region. [ABSTRACT FROM AUTHOR] more...

The photoreaction of rhodium dinuclear complex is triggered by absorption of the 510 nm light and has included two important processes. The large decrease in the activation energy for the parallel Cp* in [[(RhCp*).sub.2][([mu]-C[H.sub.2]).sub.2]([mu]-[O.sub.2]SOSO)] is attributed to the relaxation of molecular stress via a stereospecific oxygen-atom rearrangement, which has shown that the rotational motion of the Cp* ligands is coupled to the photochromism. more...

Description about the reaction of [((super)AdArO)3tacn)UIII] with tetramethylimidazol-2-ylidene is given, which yields novel N-heterocyclic carbene complexes [((super)AdArO)3tacn)UIII(Me4IMC:)] (2) and [((Me3Si)2N)3UIII(Me4IMC:)] (4). It is concluded that novel N-heterocyclic carbene complexes of U(III) were successfully synthesized and fully characterized. more...

The present study described the histologic findings of 2 implants and surrounding tissues retrieved from human irradiated bone. For the treatment of a malignant tumor, 50 Gy of irradiation after implant placement and 60 Gy of irradiation before implant placement were provided for patients 1 and 2, respectively. In patient 1, the implant and surrounding tissues were removed from the frontal bone 24 months after implant placement because of the patient's death from a tumor recurrence. In patient 2, the implant and surrounding tissues were removed from a maxillectomy site 26 months after implant placement because of tumor recurrence. In each patient, new bone formation surrounding the implants was observed. The ratio of direct bone-implant contact along the threaded implant surface was 61.3% in patient 1 and 69.0% in patient 2. The ratio of the area occupied by mineralized bone in each thread was 75.8% in patient 1 and 81.2% in patient 2. These results indicate the potential of irradiated bone to achieve osseointegration of titanium implants. [ABSTRACT FROM AUTHOR] more...

The X-ray diffraction analysis of a series of alkane adducts of the low-valent, coordinatively unsaturated, tris-aryl oxide uranium (III) complex [((ArO)(sub 3) tacn)U] is presented. Results support a weak metal-alkane orbital function, observed eta square -H, C coordination mode, a slightly larger calculated U-C and U-H distance attributing to the missing ligand-alkane interactions in crystal structure. more...

Conventionally, for dental reconstruction after bone grafting of the congenital residual alveolar cleft, a fixed prosthesis or removable partial denture is used. In this paper, residual alveolar cleft reconstruction with an osseointegrated implant following secondary bone grafting is described. The patient underwent secondary bone grafting of the residual alveolar cleft at the age of 18 years. One osseointegrated implant was placed in the bone bridge 8 months after bone grafting. No problems up to 1 year after the fabrication and placement of the fixed prosthesis have been observed. [ABSTRACT FROM AUTHOR] more...

Osteoporosis is a relative contraindication for osseointegrated implants. This article describes a patient with severe osteoporosis who underwent implant therapy in the mandible. The treatment was carried out in a conventional manner, except for a longer healing period (6 months). All implants had clinically osseointegrated. Furthermore, there was no problem after the superstructure was placed. [ABSTRACT FROM AUTHOR] more...

A pH dependent H2-activation cycle coupled to reduction of nitrate ion promoted by Cp*Ir complexes is detailed. In a pH range of about 1-4, an aqueous HNO3 solution of [Cp*Ir(super III)(H2O)3](super 2+) reacts with 3 equiv of H2 to yield a solution of [(Cp*Ir(super III))2(micron-H)3](super +) as a result of the heterolytic hydrogen activation. more...