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1.
Biomedicines ; 11(2)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36830981

RESUMO

BACKGROUND: This study aimed to investigate the effect of the vibration of osteoblasts on the cell cycle, cell differentiation, and aging. MATERIALS AND METHODS: Primary maxilla osteoblasts harvested from eight-week-old mice were subjected to vibration at 3, 30, and 300 Hz once daily for 30 min; control group, 0 Hz. A cell proliferation assay and Cell-Clock Cell Cycle Assay were performed 24 h after vibration. Osteoblast differentiation assay, aging marker genes, SA-ß-Gal activity, and telomere length (qPCR) were assayed two weeks post- vibration once every two days. RESULTS: Cell proliferation increased significantly at 30 and 300 Hz rather than 0 Hz. Several cells were in the late G2/M stage of the cell cycle at 30 Hz. The osteoblast differentiation assay was significantly higher at 30 Hz than at 0 Hz. Runx2 mRNA was downregulated at 30 Hz compared to that at 0 Hz, while osteopontin, osteocalcin, and sclerostin mRNA were upregulated. p53/p21, p16, and c-fos were activated at 30 Hz. SA-ß-Gal activity increased significantly at 30 or 300 Hz. Telomere length was significantly lower at 30 or 300 Hz. CONCLUSIONS: The results suggest that providing optimal vibration to osteoblasts promotes cell cycle progression and differentiation and induces cell aging.

2.
Sci Adv ; 8(51): eabq7281, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36542708

RESUMO

Floquet engineering is a promising way of controlling quantum system with photon-dressed states on an ultrafast time scale. So far, the energy structure of Floquet states in solids has been intensively investigated. However, the dynamical aspects of the photon-dressed states under ultrashort pulse have not been explored yet. Their dynamics become highly sensitive to the driving field transients, and thus, understanding them is crucial for ultrafast manipulation of a quantum state. Here, we observed the coherent exciton emission in monolayer WSe2 at room temperature at the appropriate photon energy and the field strength of the driving light pulse using high-harmonic spectroscopy. Together with numerical calculations, our measurements revealed that the coherent exciton emission spectrum reflects the diabatic and adiabatic dynamics of Floquet states of excitons. Our results provide a previosuly unexplored approach to Floquet engineering and lead to control of quantum materials through pulse shaping of the driving field.

3.
Materials (Basel) ; 15(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36143782

RESUMO

The buildup of corrosion products over a reinforcing bar and associated reduction in rib height lead to degradation of the bond between reinforcement and concrete. The authors have previously used digital image correlation (DIC) to visualize and quantify load-induced cracking at the interface in specimens with varying degrees of corrosion. The results obtained in that study are used here to simulate the post-corrosion local bond behavior. A bond degradation model is incorporated into the discrete analysis tool, 3D Rigid Body Spring Model (RBSM) for the simulation. This analysis method allows the shape of the reinforcing bar to be directly modeled, and concrete cracking behavior is simulated by using a randomly shaped mesh. The magnitude of opening and sliding over the tips of ribs in the simulation, in which the reduction in rib height could not be modeled, is significantly lower than observed in the experiment. The results demonstrate that reduction in rib height is an important factor in post-corrosion behavior, and needs to be included in simulation models. It is also understood that in order to gain a better understanding of local post-corrosion bond behavior, de-bonding between reinforcement and concrete needs to be modeled in a discrete analysis framework.

4.
Sci Rep ; 12(1): 1615, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136097

RESUMO

Parameter optimization is a long-standing challenge in various production processes. Particularly, powder film forming processes entail multiscale and multiphysical phenomena, each of which is usually controlled by a combination of several parameters. Therefore, it is difficult to optimize the parameters either by numerical-model-based analysis or by "brute force" experiment-based exploration. In this study, we focus on a Bayesian optimization method that has led to breakthroughs in materials informatics. Specifically, we apply this method to exploration of production-process-parameter for the powder film forming process. To this end, a slurry containing a powder, polymer, and solvent was dropped, the drying temperature and time were controlled as parameters to be explored, and the uniformity of the fabricated film was evaluated. Using this experiment-based Bayesian optimization system, we searched for the optimal parameters among 32,768 (85) parameter sets to minimize defects. This optimization converged at 40 experiments, which is a substantially smaller number than that observed in brute-force exploration and traditional design-of-experiments methods. Furthermore, we inferred the mechanism corresponding to the unknown drying conditions discovered in the parameter exploration that resulted in uniform film formation. This demonstrates that a data-driven approach leads to high-throughput exploration and the discovery of novel parameters, which inspire further research.

5.
Materials (Basel) ; 14(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499289

RESUMO

The application of reinforced concrete for permanent and temporary deep ocean structures has recently become more prevalent; however, the static and dynamic effects of high water pressure on concrete remain unexplored. This paper investigates the influence of high water pressure (60 MPa) on four series of concrete cylinders with and without an embedded steel bar under sustained and cyclic loading conditions. The residual compressive strength, bond strength, and associated evolution of surface and internal damage are evaluated after exposing concrete cylinders to a water pressure of 60 MPa. The first series is exposed to sustained water pressure for 7 and 60 days, while the other series is tested under repeated water pressure for 10, 20, 30, 60, and 150 cycles. The results reveal that residual compressive strength falls immediately by 16% within 7 days of sustained high water pressure, but the strength then remains stable up to 60 days. Under repeated high water pressure, residual compressive strength gradually reduces by up to 40% until 60 cycles, after which it remains reasonably stable until 150 cycles as crack propagation is arrested at a certain depth within the concrete cylinders. The bond strength between the steel bar and matrix is observed to decrease considerably under repeated cycles of 60 MPa water pressure up to 26%. The damage gradually propagates at the matrix/steel bar interface under the repeated water pressure, resulting in a reduction in residual pullout capacity.

6.
Front Immunol ; 12: 753754, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069529

RESUMO

Recently, it has been reported that γδ T cells are associated with the pathology of rheumatoid arthritis (RA). However, there are many uncertainties about their relationship. In this study, we investigated the morphological and histological properties of peripheral as well as temporomandibular joints (TMJ) in a mouse model of rheumatoid arthritis with and without exposure to mechanical strain on the TMJ. Collagen antibody-induced arthritis (CAIA) was induced by administering collagen type II antibody and lipopolysaccharide to male DBA/1JNCrlj mice at 9-12 weeks of age, and mechanical stress (MS) was applied to the mandibular condyle. After 14 days, 3D morphological evaluation by micro-CT, histological staining (Hematoxylin Eosin, Safranin O, and Tartrate-Resistant Acid Phosphatase staining), and immunohistochemical staining (ADAMTS-5 antibody, CD3 antibody, CD45 antibody, RORγt antibody, γδ T cell receptor antibody) were performed. The lower jawbone was collected. The mandibular condyle showed a rough change in the surface of the mandibular condyle based on three-dimensional analysis by micro-CT imaging. Histological examination revealed bone and cartilage destruction, such as a decrease in chondrocyte layer width and an increase in the number of osteoclasts in the mandibular condyle. Then, immune-histological staining revealed accumulation of T and γδ T cells in the subchondral bone. The temporomandibular joint is less sensitive to the onset of RA, but it has been suggested that it is exacerbated by mechanical stimulation. Additionally, the involvement of γδ T cells was suggested as the etiology of rheumatoid arthritis.


Assuntos
Artrite Experimental , Artrite Reumatoide , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T , Articulação Temporomandibular , Animais , Artrite Experimental/imunologia , Artrite Experimental/patologia , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Masculino , Camundongos , Linfócitos T/imunologia , Linfócitos T/patologia , Articulação Temporomandibular/imunologia , Articulação Temporomandibular/patologia
7.
Nano Lett ; 20(8): 6215-6221, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32787188

RESUMO

High-harmonic generation (HHG), which is the generation of light with multiple optical harmonics, is an unconventional nonlinear optical phenomenon beyond the perturbation regime. HHG, which was initially observed in gaseous media, has recently been demonstrated in solid-state materials. Determining how to control such extreme nonlinear optical phenomena is a challenging subject. Here, we demonstrate the control of HHG through tuning the electronic structure and carrier injection using single-walled carbon nanotubes (SWCNTs). We reveal systematic changes in the high-harmonic spectra of SWCNTs with a series of electronic structures ranging from a metal structure to a semiconductor structure. We demonstrate enhancement or reduction of harmonic generation by more than 1 order of magnitude by tuning the electron and hole injection into the semiconductor SWCNTs through electrolyte gating. These results open a path toward the control of HHG in the context of field-effect transistor devices.

8.
Nat Commun ; 10(1): 3709, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31420551

RESUMO

High-harmonic generation in solids is a unique tool to investigate the electron dynamics in strong light fields. The systematic study in monolayer materials is required to deepen the insight into the fundamental mechanism of high-harmonic generation. Here we demonstrated nonperturbative high harmonics up to 18th order in monolayer transition metal dichalcogenides. We found the enhancement in the even-order high harmonics which is attributed to the resonance to the band nesting energy. The symmetry analysis shows that the valley polarization and anisotropic band structure lead to polarization of the high-harmonic radiation. The calculation based on the three-step model in solids revealed that the electron-hole polarization driven to the band nesting region should contribute to the high harmonic radiation, where the electrons and holes generated at neighboring lattice sites are taken into account. Our findings open the way for attosecond science with monolayer materials having widely tunable electronic structures.

10.
J Matern Fetal Neonatal Med ; 31(15): 2007-2012, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28532193

RESUMO

PURPOSE: To investigate the association between glycated albumin (GA) in diabetic mothers and complications in their children, and to determine GA cutoff values for predicting complications in infants. MATERIALS AND METHODS: This hospital-based case-control study involved 71 Japanese diabetic mothers and their children. Mean GA values were compared between mothers of infants with and without complications, and relationship with number of complications was analyzed by Pearson's correlation. Receiver operating characteristic analysis determined GA cutoff values for complications in infants. RESULTS: GA was significantly higher in mothers of children with neonatal hypoglycemia (15.8 ± 3.2 versus 12.6 ± 1.2%, p <.001), respiratory disorders (15.7 ± 3.6 versus 12.9 ± 1.9%, p <.001), hypocalcemia (15.9 ± 3.7 versus 13.1 ± 1.8%, p <.001), polycythemia (15.7 ± 2.3 versus 13.8 ± 2.1%, p =.009), myocardial hypertrophy (16.1 ± 3.7 versus 13.1 ± 2.3%, p <.001), and large-for-date status (15.8 ± 2.4 versus 13.7 ± 3.1%, p = .006), showing significant positive correlation with number of complications in infants (r = .704, 95%CI: 0.579-0.797, p < .001). Cut-off values were within the limits of 13.6-14.7%. CONCLUSIONS: GA is useful for predicting pregnancy outcomes in mothers with diabetes and must be maintained at low levels to prevent complications in infants.


Assuntos
Diabetes Gestacional/sangue , Doenças do Recém-Nascido/epidemiologia , Gravidez em Diabéticas/sangue , Albumina Sérica/metabolismo , Adulto , Biomarcadores/sangue , Feminino , Hemoglobinas Glicadas/metabolismo , Produtos Finais de Glicação Avançada , Humanos , Recém-Nascido , Japão/epidemiologia , Valor Preditivo dos Testes , Gravidez , Curva ROC , Estudos Retrospectivos , Albumina Sérica Glicada
11.
J Gastroenterol ; 45(5): 488-500, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20049485

RESUMO

BACKGROUND: Effective biomarkers for discrimination between ulcerative colitis (UC) and Crohn's disease (CD) have not been established yet. In this study, we analyzed protein profiles of peripheral blood mononuclear cells (PBMCs) of the patients to find such a biomarker. METHODS: Peripheral blood mononuclear cell proteins from 17 UC patients, 13 CD patients, and 17 healthy controls were separated by two-dimensional gel electrophoresis. The intensities of individual protein spots were subjected to discriminant analysis of UC and CD using the SIMCA-P+program. RESULTS: We found that 547 protein spots were commonly detected among the UC, CD, and healthy groups. Orthogonal partial least squares-discriminant analysis using 276 protein spots clearly discriminated the UC patients from the CD patients (R (2) 0.994; Q (2) 0.462). A similar analysis using a further selected 58 protein spots showed higher performance for discrimination of the diseases (R (2) 0.948; Q (2) 0.566). Eleven out of the 58 protein spots were successfully identified; these were functionally related to inflammation, oxidation/reduction, the cytoskeleton, endocytotic trafficking, and transcription. In addition, the PBMC protein profiles were useful for the prediction of disease activity in the UC and the CD patients, and they were also useful for predicting disease severity and responses to treatments in the UC patients. CONCLUSIONS: PBMC protein profiles are useful for the discrimination of UC from CD. The profiles could be a potent biomarker for the differential diagnosis of these diseases. Further investigation of the proteins which contributed to the discrimination could promote elucidation of the pathophysiology of UC and CD.


Assuntos
Proteínas Sanguíneas/metabolismo , Colite Ulcerativa/sangue , Colite Ulcerativa/diagnóstico , Doença de Crohn/sangue , Doença de Crohn/diagnóstico , Leucócitos Mononucleares/metabolismo , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Colite Ulcerativa/patologia , Doença de Crohn/patologia , Diagnóstico Diferencial , Análise Discriminante , Feminino , Humanos , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Adulto Jovem
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