105 research outputs found
Spinorial Wheeler-DeWitt wave functions inside black hole horizons
We revisit the solutions of the Wheeler-DeWitt (WDW) equation inside the
horizons of spherical black holes and planar topological black holes in
arbitrary dimensions. For these systems, the solutions of the equations are
found to have the same form. Therefore, Yeom's Annihilation-to-nothing
interpretation can be applied to each case. We have introduced the Dirac-type
WDW equations into quantum cosmology in a recent paper, so we also apply our
formulation to the quantum theory of the interior of the black hole in order to
obtain the solution of the spinorial wave function. The shape of the wave
packet of the spinorial WDW wave function indicates that the variation of
Yeom's interpretation holds in this scheme.Comment: 15 pages, 3 figures. Title slightly modifie
Classical and quantum bicosmology with noncommutativity
Recently, Falomir, Gamboa, Mendez, Gondolo and Maldonado proposed a
bicosmology scenario [1-4] for solving some cosmological problems related to
inflation, dark matter, and thermal history of the universe. Their plan is to
introduce noncommutativity into the momentum space of the two scale factors. In
the present paper, we revisit their model and first consider exact classical
solutions in the model with constant noncommutativity between dynamical
variables and between canonical momenta. We also hypothesize that the
noncommutativity appears when the scale factors are small, and show the
behavior of the classical solution in that case with momentum-space
noncommutativity. Finally, we write down the Wheeler-DeWitt equation in that
case and examine the behavior of the solution.Comment: 19 pages, 15 figures. Revised versio
A First View of the Effect of a Trial of Early Mobilization on the Muscle Strength and Activities of Daily Living in Mechanically Ventilated Patients With COVID-19
Objective: To retrospectively investigate the effect of early mobilization on the muscle strength and activities of daily living in patients with COVID-19 under mechanical ventilation. Design: This was a single-center, retrospective, observational study. Setting: Inpatient rehabilitation care in Japan. Participants: The study subjects were divided based on the onset of mobilization: under mechanical ventilation (n=17; aged 68.5±11.9, 13 male) and after extubation (n=11; aged 59.7±7.1, 6 male; N=28). Interventions: Mobilization, including dangle sitting, standing, walking, and muscle strengthening exercises. Main Outcome Measures: The outcome measures were Barthel Index, Medical Research Council Manual Muscle Test, and intensive care unit Mobility Scale. Results: The difference in the Barthel Index, Medical Research Council Manual Muscle Test, and intensive care unit Mobility Scale scores pre- and postintervention were not statistically significant between the 2 groups, but all significantly improved after the intervention. Conclusion: This small sample size study found no difference in the functional recovery of patients with severe COVID-19 who underwent early mobilization under mechanical ventilation relative to when it was begun after extubation
Multiscale structural control of linked metal–organic polyhedra gel by aging-induced linkage-reorganization
Assembly of permanently porous metal–organic polyhedra/cages (MOPs) with bifunctional linkers leads to soft supramolecular networks featuring both porosity and processability. However, the amorphous nature of such soft materials complicates their characterization and thus limits rational structural control. Here we demonstrate that aging is an effective strategy to control the hierarchical network of supramolecular gels, which are assembled from organic ligands as linkers and MOPs as junctions. Normally, the initial gel formation by rapid gelation leads to a kinetically trapped structure with low controllability. Through a controlled post-synthetic aging process, we show that it is possible to tune the network of the linked MOP gel over multiple length scales. This process allows control on the molecular-scale rearrangement of interlinking MOPs, mesoscale fusion of colloidal particles and macroscale densification of the whole colloidal network. In this work we elucidate the relationships between the gel properties, such as porosity and rheology, and their hierarchical structures, which suggest that porosity measurement of the dried gels can be used as a powerful tool to characterize the microscale structural transition of their corresponding gels. This aging strategy can be applied in other supramolecular polymer systems particularly containing kinetically controlled structures and shows an opportunity to engineer the structure and the permanent porosity of amorphous materials for further applications
Five-year quality of life assessment after carbon ion radiotherapy for prostate cancer
The aim of this study was to prospectively assess 5-year health-related quality of life (HRQOL) of patients treated with carbon ion radiotherapy (C-ion RT) for clinically localized prostate cancer. A total of 417 patients received carbon ion radiotherapy at a total dose of 63–66 Gray-equivalents (GyE) in 20 fractions over 5 weeks, and neoadjuvant and adjuvant androgen deprivation therapy (ADT) were administered for intermediate and high-risk patients. A HRQOL assessment was performed at five time points (immediately before the initiation of C-ion RT, immediately after, and at 12, 36 and 60 months after completion of C-ion RT) using Functional Assessment of Cancer Therapy (FACT) questionnaires. FACT-G and FACT-P scores were significantly decreased; however, the absolute change after 60 months was minimal. The transient decreases in the Trial Outcome Index (TOI) score returned to their baseline levels. Use of ADT, presence of adverse events, and biochemical failure were related to lower scores. Scores of subdomains of FACT instruments indicated characteristic changes. The pattern of HRQOL change after C-ion RT was similar to that of other modalities. Further controlled studies focusing on a HRQOL in patients with prostate cancer are warranted
Spatiotemporal control of supramolecular polymerization and gelation of metal-organic polyhedra
In coordination-based supramolecular materials such as metallogels, simultaneous temporal and spatial control of their assembly remains challenging. Here, we demonstrate that the combination of light with acids as stimuli allows for the spatiotemporal control over the architectures, mechanical properties, and shape of porous soft materials based on metal–organic polyhedra (MOPs). First, we show that the formation of a colloidal gel network from a preformed kinetically trapped MOP solution can be triggered upon addition of trifluoroacetic acid (TFA) and that acid concentration determines the reaction kinetics. As determined by time-resolved dynamic light scattering, UV–vis absorption, and 1H NMR spectroscopies and rheology measurements, the consequences of the increase in acid concentration are (i) an increase in the cross-linking between MOPs; (ii) a growth in the size of the colloidal particles forming the gel network; (iii) an increase in the density of the colloidal network; and (iv) a decrease in the ductility and stiffness of the resulting gel. We then demonstrate that irradiation of a dispersed photoacid generator, pyranine, allows the spatiotemporal control of the gel formation by locally triggering the self-assembly process. Using this methodology, we show that the gel can be patterned into a desired shape. Such precise positioning of the assembled structures, combined with the stable and permanent porosity of MOPs, could allow their integration into devices for applications such as sensing, separation, catalysis, or drug release
Geometrical effective actions for a partially massless spin-2 field
We consider nonlinear effective actions for a spin-2 field, whose
"decoupling" limit gives Fierz-Pauli action in D dimensional maximally
symmetric spacetime. We find, especially, the effective action for a partially
massless field can take a concise geometrical form. The exact solution for time
evolution of the background metric in the model using the effective action is
also studied.Comment: 13pages, no figure. (v2
Control of seed formation allows two distinct self-sorting patterns of supramolecular nanofibers
自己組織化する分子繊維のネットワークを種形成の制御で作り分けることに成功 --人工スマートマテリアル設計の新機軸として期待--. 京都大学プレスリリース. 2020-08-26.Self-sorting double network hydrogels comprising orthogonal supramolecular nanofibers have attracted attention as artificially-regulated multi-component systems. Regulation of network patterns of self-sorted nanofibers is considered as a key for potential applications such as optoelectronics, but still challenging owing to a lack of useful methods to prepare and analyze the network patterns. Herein, we describe the selective construction of two distinct self-sorting network patterns, interpenetrated and parallel, by controlling the kinetics of seed formation with dynamic covalent oxime chemistry. Confocal imaging reveals the interpenetrated self-sorting network was formed upon addition of O-benzylhydroxylamine to a benzaldehyde-tethered peptide-type hydrogelator in the presence of lipid-type nanofibers. We also succeed in construction of a parallel self-sorting network through deceleration of seed formation using a slow oxime exchange reaction. Through careful observation, the formation of peptide-type seeds and nanofibers is shown to predominantly occur on the surface of the lipid-type nanofibers via highly dynamic and thermally-fluctuated processes
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