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We perform a full-dimensional nonadiabatic electron wavepacket study of Mn-oxide catalytic charge separation to be created on an accepting molecular system, which is of Y-shaped branching structure and has a track-branching function of proton and electron. This branching is necessary in cases where the transferred electrons and protons are to be eventually carried to mutually different destinations without quick annihilation of thus created pair (charge separation). However, as a result of the larger size of such a branching shaped acceptor, the distance between the Mn-oxide and the acceptor is so long that it can be far from obvious whether an electron is successfully delivered through conical intersections. We here show that this can really take place.

The present study proposes crack swarm inspection (CSI) for estimating crack location and size in carbon composite laminates from the surface voltage distribution. This technique generates a large number of virtual microscopic cracks, and calculates the surface voltage distribution of the composites using anisotropic electric potential functions and doublet strings. Using genetic algorithms, the virtual microscopic cracks formed a swarm to coincide with the measured surface voltage; thereby, the crack sizes and locations are estimated from the position of the crack swarm. The CSI was applied to crack detection in carbon laminated composite plates; it was confirmed that the existence of cracks in each partitioned section was detected with >80% probability, in reference to the crack location and size information. Furthermore, we also confirmed that the estimation accuracy was affected by the electric current density in the thickness direction, and addressed the recommended electrode interval based on the minimum size of the estimated crack.

This paper describes and evaluates a multistage adaptive testing (MSAT) design that was implemented for the Programme for International Student Assessment (PISA) 2018 main survey for the major domain of Reading. Through a simulation study, recovery of item-response theory model parameters and measurement precision were examined. The PISA 2018 MSAT design resulted in a parameter recovery as good as the operational benchmark, and measurement precision was improved by 4 to 5% with gains up to 10% at the extreme performance levels.

Spinel ${\mathrm{Li}}_{x}{\mathrm{Mn}}_{2}{\mathrm{O}}_{4}$ is a key cathode material that is used extensively in commercial Li-ion batteries. A challenge with this material has been that the capacity of the battery fades with cycling, an effect that can be traced to the presence of an antiferromagnetic insulator phase in the fully lithiated ${\mathrm{LiMn}}_{2}{\mathrm{O}}_{4}$ (LMO) and the associated charge disproportionation that drives distortions of the ${\mathrm{MnO}}_{6}$ octahedra. Here, by combining x-ray magnetic Compton scattering experiments with parallel first-principles computations, we show that the antiferromagnetic phase of LMO is surrounded by a robust ferrimagnetic metallic phase, which becomes stable when even a small amount of Li is removed from or added to the charge-ordered LMO. In this surprising ferrimagnetic state, charge-ordering and octahedral distortions are found to be strongly suppressed. We identify the nature of the ferrimagnetic orbitals involved through theoretical and experimental analyses of the magnetic Compton scattering spectra.

We evaluated whether the reduction of macular vessel density was correlated with the number of intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents in eyes with a branch retinal vein occlusion (BRVO). The mean vessel density was determined by optical coherence tomography angiography in 29 eyes with macular edema associated with a BRVO. Our results showed that the mean vessel density in the group that had a resolution of the macular edema after one anti-VEGF injection was significantly higher than group that had a recurrence of the macular edema (P = 0.028). Single regression analysis showed that the number of intravitreal injections was significantly correlated with the reduction of the modified vessel density (r = −0.421, P = 0.023) and systemic hypertension (r = 0.377, P = 0.044). Multiple stepwise regression analysis showed that the reduction of the modified vessel density (β = −0.442, P = 0.009) and hypertension (β = 0.403, P = 0.016) were independent factors associated with the number of intravitreal injections. We conclude that the vessel density reduction can be used to predict whether recurrences of the macular edema will develop after the initial anti-VEGF injection in eyes with macular edema associated with a BRVO.

AIM This study was performed to confirm the superior overall survival (OS) after pulmonary oligo-recurrence compared to pulmonary sync-oligometastases in a large nationwide study. PATIENTS AND METHODS Patients that met the following criteria were included: 1 to 5 lung-only metastases at the beginning of stereotactic body radiation therapy (SBRT) was performed between January 2004 and June 2015, and the biological effective dose (BED) of SBRT was 75 Gy or more. The parameters included in the analyses were age, gender, ECOG PS, primary lesion, pathology, oligoetastatic state, SBRT date, chemotherapy before SBRT, chemotherapy concurrent SBRT, chemotherapy after SBRT, maximum tumor diameter, number of metastases, field coplanarity, dose prescription, BED10, OTT of SBRT. RESULTS In total, 1,378 patients with 1,547 tumors were enrolled. Oligo-recurrence occurred in 1,016 patients, sync-oligometastases in 118, and unclassified oligometastases in 121. The three-year OS was 64.0% for oligo-recurrence and 47.5% for sync-oligometastasis (p

To realize the effective tunnel construction, it is important to grasp the characteristics of ground conditions. This paper presents an estimation method of drilling energy based on online learning from tunnel cutting face images. The proposed method realizes the estimation from a small amount of data by learning the image taken immediately before the target image using online learning since consecutive tunnel cutting faces are related to each other. The experimental results show the effectiveness of the proposed method.

Electromagnetic simulation of human body communication (HBC) was conducted to clarify the electric field distribution and signal transmission paths. Signal transmission from a transmitter to a receiver attached on the same person was analyzed by inspecting the distribution of electric field vector. Contribution of the floor was evaluated by comparing the signal transmission with/without the floor. Electric field was analyzed by using not only the vertical but also the horizontal planes for the observation plane in order to better understand the three dimensional distribution. These simulation results show the major signal transmission path in commonly adopted configuration of HBC.

We propose a set of chemical reaction mechanisms of unidirectional proton transfers, which may possibly work as an elementary process in chemical and biological systems. Being theoretically derived based on our series of studies on charge separation dynamics in water splitting by Mn oxides, the present mechanisms have been constructed after careful exploration over the accumulated biological studies on cytochrome c oxidase (CcO) and bacteriorhodopsin. In particular, we have focused on the biochemical findings in the literature that unidirectional transfers of approximately two protons are driven by one electron passage through the reaction center (binuclear center) in CcO, whereas no such dissipative electron transfer is believed to be demanded in the proton transport in bacteriorhodopsin. The proposed basic mechanisms of unidirectional proton transfers are further reduced to two elementary dynamical processes, namely, what we call the coupled proton and electron-wavepacket transfer (CPEWT) and the inverse CPEWT. To show that the proposed mechanisms can indeed be materialized in a molecular level, we construct model systems with possible molecules that are rather familiar in biological chemistry, for which we perform the ab initio calculations of full-dimensional nonadiabatic electron-wavepacket dynamics coupled with all nuclear motions including proton transfers.

We evaluated the preoperative optical coherence tomographic (OCT) findings in eyes with macula-off rhegmatogenous retinal detachment (RRD) and determined the factors that were significantly correlated with the postoperative best-corrected visual acuity (BCVA). The length of the preoperative photoreceptors was defined as the distance between the external limiting membrane (ELM) and the outer end of the outer segments of the photoreceptors in the OCT images. The mean length of the photoreceptors was 102.8 ± 28.7 µm with a range of 20 to 159 µm in eyes with RRD. The length of the preoperative photoreceptors was not significantly correlated with the preoperative BCVA but it was significantly correlated with the postoperative BCVA (r = −0.353, P = 0.003). Multivariate regression analyses revealed that the length of the photoreceptors (β = −0.388, P = 0.001) and the preoperative BCVA (β = 0.274, P = 0.021) were the only independent factors that were significantly associated with the postoperative BCVA. The length of the preoperative photoreceptors was significantly correlated with the postoperative photoreceptor length (r = 0.486, P

We presented an unusual arrhythmogenic right ventricular cardiomyopathy (ARVC) case of a late-60s elderly man’s death, due to severe pericardial/pleural effusion and ascites, and arrhythmic events, with unique pathological features. The hypertrophic heart grossly displayed yellowish to yellow-whitish predominantly in the variably thinned wall of the dilated right ventricle. Microscopic findings showed diffuse fatty/fibrofatty replacement in not only the right but left ventricular myocardium, together with an outer lymphoplasmacytic infiltrate. According to the lipid contents analysis, the triglyceride content, but not the cholesterol content, in our patient’s right and left ventricular cardiac muscle was much higher than that in the control subject. We propose that this unique triglyceride deposition in our possibly late-onset ARVC case might be one of new clues to understand its enigmatic cause. Further prospective studies are needed to validate the presence and significance of a greater volume of triglyceride deposit, after collecting and investigating a larger number of early and late-onset ARVC cases examined.

It has been reported that the macular region of the retina is displaced after vitrectomy with internal limiting membrane (ILM) peeling in eyes with macular hole (MH), but the displacements of the deeper layers of the eye, e.g. RPE and choroid are unclear following the surgery. We used optical coherence tomography (OCT) and OCT angiography (OCTA) to obtain 3 mm × 3 mm en face images before, and 2, 4, and 8 weeks following the vitrectomy with internal limiting membrane (ILM) peeling from 22 eyes of 22 patients with a MH. The OCT and OCTA images showed displacements of the fovea and choroidal intermediate vessels postoperatively. The degree of displacement of the choroid was significantly less than that of the retina (P r = −0.467, P r = 0.535, P

The present study investigates rater effects in international large-scale assessments to evaluate the construct validity of constructed-response items scored by human raters. Using the Programme for International Student Assessment data collected in 2015, we illustrate the methods and present the findings about rater effects on constructed-response items in the context of the first fully computer-based international student skill survey. By comparing the unidimensional and the two-dimensional multiple-group item response theory model, it was shown that the latent correlations between human- and machine-coded items were almost perfect. Country means of human- and machine-coded items were generally similar and their differences were small. Further investigation into individual rater effects mostly resulted in small random loadings, which implied that rater effects were negligible in most countries.

Vulcanization of rubber is performed through mechanical mixing of rubber, sulfur, and zinc oxide (ZnO). Sulfur cross-links the rubber by reacting with the double bonds in the rubber, and ZnO is an activator that efficiently accelerates the vulcanization of rubber with sulfur. The extent of coexistence of sulfur and ZnO is an important factor for ensuring effective cross-linking and sufficient dispersion. In this study, we successfully observed the spatial distributions of sulfur and zinc as well as their spatial correlation in vulcanized ethylene–propylene–diene copolymer (EPDM) rubber using microscopic X-ray fluorescence mapping with synchrotron radiation. We found that the mixing processes substantially affects the extent of coexistence of sulfur and ZnO, as well as the spatial distribution of each component. The improved spatial cross-correlation and homogeneity of sulfur and zinc enhances the performance of EPDM rubber.

Liquid-phase synthesis for solid electrolytes has received considerable attention owing to its shape control, with the potential to produce particles easily on a large scale, and its low cost and energy consumption. However, solid electrolytes prepared through liquid-phase synthesis have been shown to have lower ionic conductivity than solid electrolytes prepared through the mechanical milling method. Recently, following various efforts, our group found that the crystallinity and remaining intermediate are the reasons for the low ionic conductivity of these materials. By using tetrahydrofuran (THF), we successfully improved the ionic conductivity of Li3PS4 to 1.85 × 10−4 S cm−1 at 25 °C, higher than that afforded by ethyl propionate, which was reported to produce the highest ionic conductivity among the solvents used for liquid-phase synthesis. High-energy X-ray diffraction (XRD) measurements coupled with pair distribution function (PDF) analysis were employed to analyze the synthesized materials in order to determine why the ionic conductivity was higher than that of a sample prepared using ethyl propionate. The PDF analysis revealed that the crystallization of Li3PS4 can be suppressed using THF, which has a lower boiling point than ethyl propionate. Moreover, it was revealed that the solvent could not be removed completely when the material has an amorphous structure, and thus, the ionic conductivity was lower than that of a material prepared using the solid-phase synthesis method.

Voltage and capacity decay problems of Li2MnO3-based lithium rich layered cathode materials are still unsolved, which are the major barriers for its practical application. Intensive investigations of their mechanisms have been proceeded in recent years, which clarify cation ordered arrangement and spinel deterioration are culprits in structural aspect. Herein, we conduct various analyses to a rocksalt type Li2Nb0·15Mn0·85O3, whose first charge process is along with primary oxygen redox as Li2MnO3, but subsequently shows much better capacity retention. This material suffers from severe voltage decay and overpotential during the cycle but hard X-ray diffraction indicates it can remain rocksalt structure without any tendency of spinel deterioration or cation ordering even with massive lithium vacancies. XAS results further show there is no evident oxygen redox activity from the second cycle, while the redox range of Mn nearly has no change during the cycle. Our results demonstrate that disordered lithium rich cathode materials could be promising to exhibit highly reversible capacity upon long cycling, and their voltage decay problem could be easier to be solved for different mechanism from layered one.

Li-rich solid solution cathode materials having 3d transition metals or 4d transition metals are the candidate of next generation cathode material. In order to clarify the rate performance of 3d or 4d transition metal oxides, we focused two typical Li-rich solid solution cathodes; Li1.2Ni0.13Co0.13Mn0.54O2 as a model of 3d transition metal oxide and Li1.2Ni0.13Co0.13Ru0.54O2 cathode as a model solid solution cathode containing 4d transition metal. We have applied operando hard and soft X-ray absorption spectroscopies clarify electronic and local distortion of both cathodes. From the results of XAS measurements, the reaction mechanism of Li1.2Ni0.13Co0.13Ru0.54O2 cathode was clearly explained by reversible transition metal redox reaction without the oxygen redox process. The EXAFS analysis suggests that Li1.2Ni0.13Co0.13Ru0.54O2 cathode also had the small distorted structure around Ru compared with around Mn of Li1.2Ni0.13Co0.13Mn0.54O2 cathode. The small distorted structure takes advantages for Li+ diffusion, resulting in the high rate performance of the Li1.2Ni0.13Co0.13Ru0.54O2 cathode.

The electrochemical reactions occur on the carbon-supported platinum covered by a proton conducting polymer electrolyte. Thus, it is important to clarify the correlation between proton conductivity and morphology of the polymer electrolyte on Pt or carbon. In this study, the properties of thin films (50–200 nm) of Nafion®, which is the typical polymer electrolyte, were investigated on platinum and carbon substrates. Grazing-incidence small/wide angle X-ray scattering and electrochemical impedance spectroscopy were used to extract morphological and proton transport information. Self-designed interdigitated array electrodes were utilized to test and compare the proton conductivity on the Pt and carbon substrates. Based on the results, the difference in anisotropic behavior of Nafion thin films on each substrate were explored, which exhibit that the proton conductivity of Pt-supported Nafion thin films has more well defined hydrophilic domain structure than that of carbon supported thin films along in-plane direction and while it showed the opposite trend in the out-of-plane direction. These datasets and analyses represented a thorough study of the behavior of Nafion thin films on model substrates of interest, i.e., Pt catalyst/carbon electrodes. These results are expected to further understanding the difference in term of proton transport pathway.

The surface chemistry of perovskite-type lanthanum transition metal oxides is an important parameter in high-temperature electrochemical devices such as solid oxide fuel cells (SOFCs). Strontium segregation on the surface of lanthanum strontium cobalt oxides (LSC) may lead to poor oxygen reduction kinetics. However, previous studies have not sufficiently addressed the oxide surface chemistry, including the oxidation change of LSC under cathodic polarization. In this study, operando total-reflection X-ray fluorescence absorption and X-ray fluorescence spectroscopy were performed to investigate cathodic polarization at high temperature (773 K) and at 1 atm pressure. Dense thin-film electrodes of La0.6Sr0.4CoO3 (LSC113) on Zr0.92Y0.08O1.96 electrolytes with a gadolinium-doped ceria interlayer were examined as model SOFC cathodes. This may be the first time that predominant surface reduction of cobalt is directly observed by using LSC113 under cathodic polarization. This phenomenon is related to strontium enrichment on the LSC surface. (La0.5Sr0.5)2CoO4 decoration on LSC113 enhanced the oxygen reduction kinetics compared with that of bare LSC113. This is due to the suppression of cobalt surface reduction and Sr enrichment in the LSC113 phase.

When a voluntary action is followed by a sensory outcome, their timings are perceived to shift toward each other compared to when they were generated independently. Recent studies have tried to explain this temporal binding effect based on the cue integration theory, in which the timing of action and outcome are estimated as a precision-weighted average of their individual estimates, although distinct results were obtained between the binding of action and outcome. This study demonstrates that cue integration underlies both action and outcome bindings, using visual changes as action outcomes. Participants viewed a moving clock presented on a screen to report the onset time of their action or the feature changes of visual objects that were relevant or irrelevant to the clock movement. The results revealed that the precision of outcome timing judgment was different based on the object that underwent a feature change. Moreover, consistent with the theory's prediction, the perceptual shifts of action and outcome timings were larger and smaller, respectively, when the precision of outcome timing judgments was higher. These results suggest that cue integration serves as a common mechanism in action and outcome bindings.

We systematically assessed the relationships between growth of four components of verbal ability—Information, Similarities, Vocabulary, and Comprehension subtests of the Wechsler Intelligence Scale–Revised—and longitudinal growth from Grades 1 to 9 of the Woodcock–Johnson Psycho-Educational Battery Passage Comprehension subtest while controlling for Word Identification and Word Attack, using multilevel growth models on a sample of 414 children. Growth was assessed over all grades (1-9), and separately for early grades (1-5) and later grades (5-9). Over all grades, growth in Word Identification had a substantial standardized loading to Passage Comprehension, and all four verbal abilities had smaller, but significant standardized loadings to Passage Comprehension ( p < .05), with Information and Vocabulary having slightly higher loadings than Similarities and Comprehension. For early grades, results were similar to the overall results, with the exception of Vocabulary, which had a nonsignificant loading to Passage Comprehension. For later grades, Word Identification again had the largest, but substantially smaller standardized loading on Passage Comprehension and standardized loadings of all four verbal abilities were statistically significant with Vocabulary and Wechsler Intelligence Scale for Children–Revised (WISC-R) Comprehension having appreciably higher loadings than in the previous analyses. Conversation- and interaction-based intervention and instruction in oral language in general, and vocabulary in particular throughout early childhood and continuing throughout the school years, combined with evidence-based instruction that systematically develops the skills of phonologic awareness, decoding, word reading, fluency, and comprehension in school, may provide a pathway to reducing the achievement gap in reading.

Clarification of the interaction between the electrode and the electrolyte is crucial for further improvement of the performance of lithium-ion batteries. We have investigated the structural change at the interface between the surface of a 104- oriented epitaxial thin film of LiCoO2 (LiCoO2(104)), which is one of the stable surfaces of LiCoO2, and an electrolyte prepared using a carbonate solvent (1 M LiClO4 in ethylene carbonate and dimethyl carbonate) by in situ neutron reflectivity measurements. Owing to the decomposition of the organic solvent, a new interface layer was formed after contact of LiCoO2(104) with the electrolyte. The composition and thickness of the interface layer changed during Li+ extraction/insertion. During Li+ extraction, the thickness of the interface layer increased and the addition of an inorganic species is suggested. The thickness of the interface layer decreased during Li+ insertion. We discuss the relationship between battery performance and the dynamic behavior at the interface.

In this perspective article, we review, along with presenting new results, a series of our theoretical analyses on the excited-state mechanism of charge separation (proton–electron pair creation) relevant to the photoinduced water-splitting reaction (2H 2 O → 4H + + 4e − + O 2 ) in organic and biological systems, which quite often includes Mn clusters in various molecular configurations. The present mechanism is conceived to be universal in the triggering process of the photoexcited water splitting dynamics. In other words, any Mn-based catalytic charge separation is quite likely to be initiated according to this mechanism. As computationally tractable yet realistic models, we examine a series of systems generally expressed as X–Mn–OH 2 ⋯A, where X = (OH, Ca(OH) 3 ) and A = ( N -methylformamidine, guanidine, imidazole or ammonia cluster) in terms of the theory of nonadiabatic electron wavepacket dynamics. We first find both an electron and a proton are simultaneously transferred to the acceptors through conical intersections upon photoexcitation. In this mechanism, the electron takes different pathways from that of the proton and reaches the densely lying Rydberg-like states of the acceptors in the end, thereby inducing charge separation. Therefore the presence of the Rydberg-like diffused unoccupied states as an electron acceptor is critical for this reaction to proceed. We also have found another crucial nonadiabatic process that deteriorates the efficiency of charge separation by rendering the created pair of proton and electron back to the originally donor site through the states of d–d band originated from Mn atom. Repetition of this process gradually annihilates the created pair of proton and electron in a way different from the usual charge recombination process. We address this dynamics by means of our proposed path-branching representation. The dynamical roles of a doped Ca atom are also uncovered, which are relevant to controlling the pathways of electron flow and moreover to reduction of the annihilation dynamics of proton–electron pair.

Numerical representations influence temporal processing. Previous studies have consistently shown that larger numbers are perceived to last longer than smaller ones. However, whether this effect is modulated by the absolute or relative magnitudes of the numbers has yet to be fully understood. Here, participants observed single- and double-digit Arabic numerals in separate experimental blocks and reproduced stimulus duration of 600 or 1200 ms. Our results replicated previous findings that the duration of larger numbers was reproduced longer than that of smaller numbers within each digit set. Although the effect of numerical magnitude across single- and double-digit numerals was found when the numerals were presented for 600 ms, the difference was negligible when they were presented for 1200 ms, suggesting that relative magnitude is an important factor in the number-time interaction in the suprasecond range. These results suggest that contextual influence on number-time interaction may depend on the actual stimulus duration.

Ferrocene (FeCp2) is adsorbed within the pores of activated carbon (AC) in the gas phase. A large AC/FeCp2 contact interface enables fast charging and discharging of the resulting AC/FeCp2 hybrids at as high as 3.6–4.0 V vs. Li/Li+ by using ionic liquid electrolytes. Meanwhile, aqueous and organic electrolytes induce desorption of the adsorbed FeCp2 upon electrolyte impregnation. A charging (i.e., oxidation) process of the hybrids also accelerates the desorption because the resulting ferrocenium ion (FeCp2+) is pulled to an oppositely (i.e., negatively) charged counter electrode. Ionic liquids shield such attractive forces and prevent desorption of FeCp2.

In order to develop suitable cathodes for practical magnesium rechargeable batteries, it is important to understand the differences between the mechanisms of lithium ions and magnesium ions insertion/extraction reactions in cathode materials. We used olivine-type FePO4 as a model material to examine the mechanism of magnesium ions insertion/extraction reactions by performing galvanostatic measurements, X-ray absorption spectroscopy, and synchrotron X-ray diffraction (XRD) analysis. The equilibrium potential of MgxFePO4 gradually changed with magnesium ions insertion/extraction. In the XRD patterns of MgxFePO4, the only peak shift was observed without second phase formation. It was proved that the magnesium ions insertion/extraction in FePO4 proceeded not by a two-phase reaction, but by a single-phase reaction.

Li2TiO3 is a Li-rich cathode/anode material similar to Li2MnO3. These materials crystallize into monoclinic structures with ABC-stacked atomic layers, approximated by pseudo-trigonal cells. In these crystals, transition-metal layers are occupied not only by transition-metal atoms but also by Li atoms, forming ordered/disordered atomic arrangements. Faults Rietveld analysis was conducted, showing that Li2TiO3 crystalizes into a monoclinic structure with the space group C2/c, in which Li and Ti atoms are configured in an imperfectly ordered arrangement at the transition-metal layer and a large number of stacking faults are generated in the crystal. To precisely evaluate the site occupancies in such imperfect crystals, our structural analysis found that the structures should be analyzed by powder diffraction while taking stacking faults and atomic mixing into account. The atomic mixing at the transition-metal layer tends to gradually increase as the synthesis temperature is raised.

We theoretically propose a photoinduced water-splitting cycle catalyzed by a binuclear Mn oxo complex. In our “bottom-up approach” to this problem, we once proposed a working minimal model of water-splitting cycle in terms of a mononuclear Mn oxo complex as a catalyst along with water clusters [K. Yamamoto and K. Takatsuka, Phys. Chem. Chem. Phys. 20, 6708 (2018)]. However, this catalyst is not self-contained in that the cycle additionally needs buffering molecules for electrons and protons in order to reload the Mn complex with electrons and protons, which are lost by photoinduced charge separation processes. We here show that a binuclear Mn oxo complex works as a self-contained photocatalyst without further assistant of additional reagents and propose another catalytic cycle in terms of this photocatalyst. Besides charge separation and proton relay transfer, the proposed cycle consists of other fundamental chemical dynamics including electron–proton reloading, radical relay-transfer, and Mn reduction. The feasibility of the present water-splitting cycle is examined by means of full dimensional nonadiabatic electron–wavepacket dynamics based on multireference electronic wavefunctions and energy profiles estimated with rather accurate quantum chemical methods for all the metastable states appearing in the cycle.We theoretically propose a photoinduced water-splitting cycle catalyzed by a binuclear Mn oxo complex. In our “bottom-up approach” to this problem, we once proposed a working minimal model of water-splitting cycle in terms of a mononuclear Mn oxo complex as a catalyst along with water clusters [K. Yamamoto and K. Takatsuka, Phys. Chem. Chem. Phys. 20, 6708 (2018)]. However, this catalyst is not self-contained in that the cycle additionally needs buffering molecules for electrons and protons in order to reload the Mn complex with electrons and protons, which are lost by photoinduced charge separation processes. We here show that a binuclear Mn oxo complex works as a self-contained photocatalyst without further assistant of additional reagents and propose another catalytic cycle in terms of this photocatalyst. Besides charge separation and proton relay transfer, the proposed cycle consists of other fundamental chemical dynamics including electron–proton reloading, radical relay-transfer, and Mn reduction. T...

The time course of the changes in the optic nerve head (ONH) blood flow in response to changes in the ocular perfusion pressure (OPP) induced by an artificial elevation of the intraocular pressure (IOP) has not been determined. We measured the blood flow, represented by the mean blur rate (MBR), on the ONH determined by laser speckle flowgraphy. The MBR was determined before, during, and after the IOP was elevated by 20 or 30 mmHg by pressure applied on the eye by an ophthalmodynamometer in a total of 27 healthy eyes. For an IOP elevation of 20 mmHg, the percentage reduction in the MBR-vessel was −24.7%, and in the MBR-tissue was −16.0% (P P P P P P

Supplemental Digital Content is available in the text, We sought to evaluate clinical outcomes and toxicities of radiation therapy (RT) alone compared to RT with concurrent chemotherapy (CCT) for nasopharyngeal carcinoma (NPC) treatment. We conducted a retrospective review of consecutive patients with biopsy-proven nonmetastatic NPC who underwent RT at our institution. From May 2001 to April 2015; 62 newly diagnosed NPC patients were treated with three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT) with or without CCT. The patients were classified as follows: 8% stage I, 15% stage II, 32% stage III, and 45% stage IVA/IVB. A total of 76% of tumors were World Health Organization types II or III. Acute and late toxicities were graded according to the Common Terminology Criteria for Adverse Events version 3.0. Overall survival (OS), progression-free survival (PFS), locoregional progression-free survival (LRPFS), and distant metastasis-free survival (DMFS) were analyzed. The median follow-up period for living patients was 53 months. The median actual delivered dose was 70 Gy with a range of 28 to 70 Gy in fraction sizes of 2 Gy. The estimated 5-year OS, PFS, LRPFS, and DMFS rates were 72.7%, 59.8%, 77.9%, and 84.2%, respectively. The use of CCT was a predictive factor of significantly better OS and PFS, whereas stage IV was a significant predictor of poor OS and PFS. The most severe acute toxicities included Grade 3 mucositis in 56% and Grade 3 dermatitis in 8%. Subset analysis revealed that Grade 2 xerostomia was significantly lower in the IMRT (23%) group than in the 3D-CRT (52%) group (P = .02). RT yielded favorable outcomes. CCT was associated with longer PFS and OS than RT alone.

In one type of photocatalytic dynamics of water splitting formally summarized as2H2O + 4hν + MH → 2H2O + M*H → 4H+ + 4e− + O2 + MHthe catalytic center M mainly composed of Mn oxides (clusters) along with supporting molecules like proteins is directly photoexcited and discharges electrons and protons. The mechanism can be comprehended in terms of the coupled proton electron-wavepacket transfer (CPEWT). In another type proposed in the literature, M is not directly photoexcited, and instead, lights are absorbed somewhere other than M, thereby creating complicated sequential steps (a ladder) of oxidation–reduction potential, thus sucking electrons successively from one molecular site to the next, and the final place providing electrons and protons is the catalytic center M. During charge separation dynamics, M is assumed to remain in the electronic ground state, and this type can be schematically summarized asM−H+ + Ω+ → M + H+ + Ω+e−where Ω indicates a cation species (a hole carrier) at the site of photon absorption. It is widely believed that the latter mechanism is responsible for water splitting in plants and cynobacteria, and M in photosystem II (PSII) is known to include Mn4CaO5. However, difficult questions about this mechanism of ground-state charge separation in the latter reaction arise as to whether it is quantum mechanically possible and what is it, if indeed possible? Besides, the time-constant for this reaction reported in the literature is so long, actually far longer than the time-scale for energy dissipation for inter- and intra-molecular vibrational energy redistribution, that the quantum mechanical coherence of the reaction should not be able to be maintained. More seriously, we wonder how protons and electrons can be isolated in the ground state, if any, and how they can be transferred unidirectionally (with no return)? We address these fundamental questions affirmatively by proposing a general chemical principle; collision induced charge separation dynamics in the ground state.

We theoretically studied the chemical principles behind the photodynamics of water splitting: 2H2O + 4hν + M → 4H+ + 4e− + O2 + M. To comprehend this simple looking but very complicated reaction, the mechanisms of at least three crucial phenomena, among others, need to be clarified, each of which is supposed to constitute the foundation of chemistry: (i) charge separation (4H+ + 4e−), (ii) the catalytic cycle for essentially the same reactions to be repeated by each of four photon absorptions with a catalyst M, and (iii) the generation of oxygen molecules of spin triplet. We have previously clarified the photodynamical mechanism of charge separation, which we refer to as coupled proton electron-wavepacket transfer (CPEWT), based on the theory of nonadiabatic electron wavepacket dynamics [K. Yamamoto and K. Takatsuka, ChemPhysChem, 2017, 18, 537]. CPEWT gives an idea of how charge separation can be materialized at each single photon absorption. Yet, this mechanism alone cannot address the above crucial items such as (ii) the catalytic cycle and (iii) O2 formation. In the studies of these fundamental processes, we constructed a possible minimal chemical system and perform semi-quantitative quantum chemical analyses, with which to attain insights about the possible mechanisms of photochemical water splitting. The present study has been inspired by the idea underlying the so-called Kok cycle, although we do not aim to simulate photosystem II in biological systems in nature. For instance, we assume here that a catalyst M (actually simple manganese oxides in this particular study) is pumped up to its excited states leading to charge separation by four-time photon absorption, each excitation of which triggers individual series of chemical reactions including the reorganization of the hydrogen-bonding network (cluster) of water molecules surrounding the photocatalytic center. It is shown that in the successive processes of restructuring of the relevant water cluster, the OO bond is formed and consequently an oxygen molecule of spin triplet can be isolated within a range of a given photon energy of about 3.0 eV.

The purpose of this study was to investigate an association between the prognosis for oro-hypopharynx squamous cell carcinoma treated with radiation therapy and the pre-therapeutic level of C-reactive protein (CRP). Patient with oro-hypopharyngeal squamous cell carcinoma who underwent definitive radiotherapy in our institution from January 2002 to August 2016 were enrolled. The patient were divided into elevated CRP (over 0.3 mg/dl) group and normal CRP groups, according to pre-treatment serum levels. There were 276 evaluable patients, and the median follow up was 41 months, ranging from 2 to 171 months. The 3-year OS and CSS for all enrolled patients were 67.0% and 72.8%, respectively. The OS and CSS rates were significantly worse in the elevated CRP group than in the normal CRP group, according to Kaplan-Meier survival curves analysed by a Log-rank test (p = 0.005 and p

An electron dynamics mechanism of charge separation in the initial stage of excited-state reactions of the class of XMnOH2 ⋅⋅⋅A${ \to }$XMnOH⋅⋅⋅HA (X=OH or OCaH; A=N-methylformamidine, guanidine, imidazole, or ammonia cluster) is reported. The dynamic effect of calcium doping is also revealed. This study provides a novel factor to be considered in designing efficient systems for photoinduced water splitting.

One major issue with large-scale assessments is that the respondents might give no responses to many items, resulting in less accurate estimations of both assessed abilities and item parameters. This report studies how the types of items affect the item-level nonresponse rates and how different methods of treating item-level nonresponses have an effect on item calibration and scoring.

Li2FeSiO4 is a promising cathode material for lithium ion batteries because of its theoretically high capacity if two lithium ions can be extracted/inserted per formula unit; however, the extraction/insertion of two lithium ions from Li2FeSiO4 remains a challenge. Herein, we successfully synthesized carbon-coated Li2FeSiO4 nanoparticles which exhibit a capacity commensurate to a reversible two-lithium extraction/insertion at elevated temperature. This study investigates the mechanism underlying a two lithium ion extraction/insertion in Li2FeSiO4 using synchrotron X-ray absorption spectroscopy and X-ray diffraction. Our results reveal that the contribution of the Fe-3d band is dominant for the first lithium extraction process from Li2FeSiO4 to LiFeSiO4. During the second lithium extraction process from LiFeSiO4 to FeSiO4, however, ligand holes are formed in the O-2p band rather than further oxidation of Fe3+. Structural analyses further reveal a phase transformation between Li2FeSiO4 and LiFeSiO4, while a ...

Lifetimes of lithium-ion batteries are often affected by deterioration of positive electrodes. It is well-known that the deterioration of the positive electrodes can be reduced by using electrolyte additives; however, the mechanism underlying this cyclability improvement needs to be clarified. In this study, we investigate electronic structure at the electrode/electrolyte interface using in situ total-reflection fluorescence X-ray absorption spectroscopy to elucidate the mechanism underlying the cyclability improvement of a LiCoO2 electrode upon addition of vinylene carbonate (VC) to the electrolyte. The results indicate that the reduction of cobalt ions at the surface of the LiCoO2 electrode, which occurs upon soaking in the electrolyte in the absence of VC, is suppressed by the presence of the VC additive. The VC additive also suppresses irreversible change in the electronic structure of the cobalt ions at the LiCoO2 surface during successive charge/discharge processes. The effects of the VC additive ca...

Vibrio cholerae has three sets of chemotaxis-related signaling proteins, of which only System II has been shown to be involved in chemotaxis. Here, we examined localization of green fluorescent protein (GFP)-fused components of System I. The histidine kinase (CheA1) and the adaptor (CheW0) of System I localized to polar and lateral membrane regions with standing incubation (microaerobic conditions), but their localization was lost after shaking (aerobic conditions). A transmembrane receptor of System I also showed polar and lateral localization with standing incubation. By contrast, GFP-fused components of System II localized constitutively to the flagellated pole. Nitrogen gas, sodium azide or carbonylcyanide m-chlorophenylhydrazone induced localization of CheA1-GFP even with shaking incubation, suggesting that the localization is controlled in response to changes in energy metabolism. Fluorescently labeled tetracysteine-tagged CheA1 also showed azide-induced localization, arguing against artifactual effects of GFP fusions. These results suggest that System I components are assembled into the supramolecular signaling complex in response to reduced cellular energy states, raising the possibility that the System I complex plays a role in sensing and signaling under microaerobic environments, such as in the host intestine.

Sex-related differences are present in the systemic and ocular blood flow. However, the cause of the sex-related differences has not been determined. We investigated the ocular blood flow, represented by the mean blur rate (MBR), on the optic nerve head (ONH) determined by laser speckle flowgraphy in 138 males (63.9 ± 8.9 years) and 194 females (63.5 ± 9.4 years). The correlations between the MBR on the ONH and the clinical data were determined. The overall ONH-MBR was significantly higher in females than males (P P P P P

Although scleral buckling is a well-established surgical treatment for rhegmatogenous retinal detachment (RRD), the procedure can reportedly cause problems in the ocular circulation. Segmental scleral bucking without a concomitant encircling procedure was performed on 46 eyes with successfully reattached macula-on RRD. Choroidal blood flow was assessed using laser speckle flowgraphy. Spectral-domain optical coherence tomography was used to image macular regions, to measure the subfoveal choroidal thickness (SFCT), and to calculate the luminal and the stromal areas by the binarization method preoperatively and 1, 4, 8 and 12 weeks postoperatively. Choroidal mean blur rate at the macula did not significantly change, while that at the buckle and unbuckle side significantly reduced at 8 weeks postoperatively in the operated eye (P = 0.007 and P = 0.017, respectively). The SFCT and the luminal area increased temporarily 1 week following surgery in the operated eye (P