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1.
Phys Chem Chem Phys ; 24(11): 6788-6802, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35244635

RESUMO

Silicate-containing hydroxyapatite (SiHA) particles were synthesized and functionalized with polyethylene glycol-silane (PEG-silane) for clarifying the effect of the bioceramic surface hydration layer states on the collagen (Col) fibrillation degree. Plate-like SiHA particles were obtained containing the SiO44- ion inside and/or outside the particles. PEG-silane was successfully functionalized on SiHA particles, and the hydration layer and Col adlayer states on the particles were precisely investigated for exemplifying the importance of the water molecular states at the interface. The ratio of free to intermediate water in the hydration layers of the particles decreased when containing silicate components, and it significantly increased with increasing PEG-silane molecular occupancy, where the asymmetric stretching vibration component ratio in the free water clearly increased. In a quartz crystal microbalance with dissipation (QCM-D) measurement, the frequency change (Δf) and the energy dissipation change (ΔD) values increased with Col adsorption on the particles for 32-34 min and then Δf slightly increased (or stopped increasing) and ΔD dramatically increased, indicating the effective water mobility and state changes with the Col fibrillation at the interface. The Col fibrillation degree evaluated by tan δ and the protein secondary structure of the adlayers clearly increased due to the PEG-silane functionalization, and the tendency was supported by the increase in the fibril density under SEM observation. Surprisingly, it was found that the fibrillation degree based on the protein secondary structure was significantly correlated with the asymmetric stretching vibration component ratio in the free water molecules of the hydration layer on the particles, suggesting the importance of the hydration layer states on bioceramics for controlling Col fibrillation.


Assuntos
Durapatita , Técnicas de Microbalança de Cristal de Quartzo , Adsorção , Colágeno , Durapatita/química , Silicatos
2.
Sensors (Basel) ; 22(15)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35957262

RESUMO

The diagnosis of the dynamics, accumulation, and engraftment of transplanted stem cells in vivo is essential for ensuring the safety and the maximum therapeutic effect of regenerative medicine. However, in vivo imaging technologies for detecting transplanted stem cells are not sufficient at present. We developed nanohybrid particles composed of dendron-baring lipids having two unsaturated bonds (DLU2) molecules, quantum dots (QDs), and magnetic nanoparticles in order to diagnose the dynamics, accumulation, and engraftment of transplanted stem cells, and then addressed the labeling and in vivo fluorescence and magnetic resonance (MR) imaging of stem cells using the nanohybrid particles (DLU2-NPs). Five kinds of DLU2-NPs (DLU2-NPs-1-5) composed of different concentrations of DLU2 molecules, QDs525, QDs605, QDs705, and ATDM were prepared. Adipose tissue-derived stem cells (ASCs) were labeled with DLU2-NPs for 4 h incubation, no cytotoxicity or marked effect on the proliferation ability was observed in ASCs labeled with DLU2-NPs (640- or 320-fold diluted). ASCs labeled with DLU2-NPs (640-fold diluted) were transplanted subcutaneously onto the backs of mice, and the labeled ASCs could be imaged with good contrast using in vivo fluorescence and an MR imaging system. DLU2-NPs may be useful for in vivo multimodal imaging of transplanted stem cells.


Assuntos
Nanopartículas de Magnetita , Pontos Quânticos , Animais , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/toxicidade , Camundongos , Imagem Multimodal , Pontos Quânticos/química , Células-Tronco
3.
Rinsho Ketsueki ; 61(3): 268-273, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32224589

RESUMO

This report presents the case of a 68-year-old female patient previously diagnosed with thymoma by her local doctor. She was referred to our hospital for surgery, and the thymoma was removed and diagnosed as a World Health Organization (WHO) classification type AB thymoma. After surgery, she experienced general malaise, a loss of appetite, and weight loss, so she visited our hospital in May 2019. A blood test showed hypogammaglobulinemia and low B lymphocytes. A bone marrow examination revealed no morphological abnormalities. Flow cytometric analysis indicated a marked decrease in both the B cell-related surface markers CD19 and CD20 and the T cell-related surface marker CD4, and the CD4/CD8 ratio was also low. She was diagnosed with Good's syndrome, and immunoglobulin replacement therapy was administered. She subsequently developed hemophagocytic lymphohistiocytosis (HLH) due to infection and was treated according to the HLH2004 protocol, but she finally succumbed to multiple organ damage as a result of sepsis. Given that Good's syndrome is associated with both humoral and cellular immune dysfunctions, affected patients tend to develop severe infections and have a poor prognosis. In such cases, early detection, regular immunoglobulin replacement therapy, and infection prevention therapies are important.


Assuntos
Agamaglobulinemia , Linfo-Histiocitose Hemofagocítica , Timoma , Neoplasias do Timo , Idoso , Feminino , Humanos , Timectomia
4.
J Phys Ther Sci ; 32(7): 433-438, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32753782

RESUMO

[Purpose] Most exercise therapy procedures induce hemodynamic changes and could be a cardiovascular risk. This pilot study investigated factors that induce an exaggerated increase in blood pressure during exercise therapy. [Participants and Methods] We measured the blood pressure and pulse rate before and after exercise therapy for ambulation on days 1, 2, and 7 of the exercise therapy in patients (n=23; age, 69 ± 11 years) who were hospitalized for a stroke or an orthopedic surgery. [Results] Each participant's blood pressure and pulse rate were significantly increased after the exercise therapy. Regression analysis demonstrated that the increase in systolic blood pressure was independently predicted by body weight and pulse rate before the exercise therapy. In the logistic regression analysis, age and body weight were independent predictors of the exaggerated increase in systolic blood pressure (fourth quartile). [Conclusion] A significant increase in blood pressure was induced by exercise therapy. There was a correlation between systolic blood pressure increase and pulse rate before the exercise therapy. Old age or increased body weight predicts exaggerated increase in blood pressure during exercise therapy.

5.
Opt Express ; 27(6): 8153-8167, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31052638

RESUMO

In this study, we presented the acceleration of full-color computer-generated holograms (CGHs) bi using WAvelet ShrinkAge-Based superpositIon (WASABI). The WASABI method uses a wavelet transform. Furthermore, the light wave superposition is calculated by using 3%, 5%, and 10% of the light wave components in wavelet space. The WASABI method is implemented for generating full-color CGHs and is used to further combine the color space conversion from the RGB color space to the YCbCr color space. We report that the WASABI method is 10-33 times faster than the conventional look-up table method and 2-7 times faster than the depth layer method based on fast Fourier transform. Further, the WASABI method in the YCbCr color space is approximately 1.5 times faster than that in the RGB color space.

6.
Chemistry ; 25(35): 8268-8278, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-30963643

RESUMO

The oxidation of [MII (3,5-DTBCat)(DTBbpy)] (M=Ni ([Ni]), Pd ([Pd]), and Pt ([Pt]); 3,5-DTBCat=3,5-di-tert-butylcatecholato; DTBbpy=4,4'-di-tert-butyl-2,2'-bipyridine) afforded the dimeric {[NiII (3,5-DTBSQ)(DTBbpy)](PF6 )}2 ({[Ni](PF6 )}2 ; 3,5-DTBSQ=3,5-di-tert-butylsemiquinonato) and monomeric semiquinonato (SQ) complexes [MII (3,5-DTBSQ)(DTBbpy)](PF6 ) (M=Pd ([Pd](PF6 )) and Pt ([Pt](PF6 ))). The negative solvatochromic properties of the SQ complexes allowed us to estimate the relative order of their dipole moments: [Pd](PF6 )>[Pt](PF6 )>{[Ni](PF6 )}2 . The complexes [Pd](PF6 ) and [Pt](PF6 ) adopt monomeric structures and are stable in CH2 Cl2 and toluene, whereas they gradually disproportionate at room temperature to [M] and 3,5-di-tert-butylbenzoquinone (3,5-DTBBQ) in polar solvents such as THF, MeOH, EtOH, DMF, or DMSO. The results of spectroscopic studies suggested that the oxidized nickel complex adopts a monomeric structure ([Ni](PF6 )) in CH2 Cl2 , but a dimeric structure ({[Ni](PF6 )}2 ) in the other investigated solvents. In polar solvents, {[Ni](PF6 )}2 may disproportionate to [Ni] and 3,5-DTBBQ at 323 K, thereby demonstrating a significant solvent- and metal-dependence in temperature. The relative activities of {[Ni](PF6 )}2 and [M](PF6 ) toward disproportionation are related to the electrochemically estimated Kdis values in CH2 Cl2 and DMF. The present work demonstrates that solvent polarity and the dipole moments of the SQ complexes promote disproportionation, which can be controlled by a judicious choice of the metal ion, solvent, and temperature.

9.
Sensors (Basel) ; 18(1)2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29361742

RESUMO

We have developed a real time ultraviolet (UV) imaging system that can visualize both invisible UV light and a visible (VIS) background scene in an outdoor environment. As a UV/VIS image sensor, an organic photoconductive film (OPF) imager is employed. The OPF has an intrinsically higher sensitivity in the UV wavelength region than those of conventional consumer Complementary Metal Oxide Semiconductor (CMOS) image sensors (CIS) or Charge Coupled Devices (CCD). As particular examples, imaging of hydrogen flame and of corona discharge is demonstrated. UV images overlapped on background scenes are simply made by on-board background subtraction. The system is capable of imaging weaker UV signals by four orders of magnitude than that of VIS background. It is applicable not only to future hydrogen supply stations but also to other UV/VIS monitor systems requiring UV sensitivity under strong visible radiation environment such as power supply substations.

10.
Opt Express ; 23(4): 4523-8, 2015 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-25836489

RESUMO

We demonstrate multiple-channel wavelength conversions of second harmonic and sum frequency generations in a silicon carbide photonic crystal cavity. The cavity is designed to have multiple modes including a nanocavity mode and Fabry-Pérot modes. Multiple-channel wavelength conversions in the nanocavity and Fabry-Pérot modes are shown experimentally. Furthermore, we investigate the polarization characteristics of wavelength-converted light. The experimental results of the polarization are in good agreement with calculation.

11.
Rinsho Ketsueki ; 56(12): 2456-61, 2015 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-26725355

RESUMO

An 86-year-old man presented with enlarged left submandibular, left inguinal, and superficial femoral lymph nodes. He was diagnosed with Langerhans cell sarcoma (LCS) on the basis of the histopathological findings of the left inguinal lymph node biopsy. In addition, laboratory examinations revealed normocytic normochromic anemia, and bone marrow aspiration and biopsy led to a diagnosis of idiopathic cytopenia of undetermined significance (ICUS). Because of the patient's age, he was administered a regimen of cyclophosphamide, pirarubicin, vincristine, and prednisolone (THP-COP), and achieved a partial response after six courses. However, he developed acute myeloid leukemia (AML) 11 months after completion of the THP-COP therapy, and received only supportive care until his death. LCS is an extremely rare and aggressive dendritic cell neoplasm. To the best of our knowledge, only 67 cases have been reported in the literature. There are case reports describing the concurrence of hematological malignancies. Herein, we report the first documented development of LCS in a patient with ICUS who progressed to AML, and summarize the published data on the epidemiology of and therapeutic options for LCS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sarcoma de Células de Langerhans/tratamento farmacológico , Leucemia Mieloide Aguda/tratamento farmacológico , Idoso de 80 Anos ou mais , Humanos , Sarcoma de Células de Langerhans/diagnóstico , Sarcoma de Células de Langerhans/patologia , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/patologia , Masculino , Recidiva , Indução de Remissão
12.
Rinsho Ketsueki ; 56(7): 905-10, 2015 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-26256929

RESUMO

Double- and triple-hit lymphomas (DHL/THL), high-grade B-cell lymphomas with an extremely poor prognosis, are defined by a chromosomal breakpoint affecting the MYC/8q24 locus in combination with another recurrent breakpoint. The successful use of dose-adjusted (DA) EPOCH-R in patients with MYC-positive lymphoma and Burkitt lymphoma (BL) was recently reported. A 74-year-old man with acute renal dysfunction and hyperkalemia was transferred to our emergency center by ambulance. PET-CT revealed a left renal hilar mass enveloping the abdominal para-aortic domain and bladder and hydronephrosis. High (18)F-FDG uptake revealed lymph node, peritoneum, and multiple bone metastases. Analysis of the bone marrow aspirate revealed abnormal lymphoid cells with deeply basophilic cytoplasm and numerous vacuoles resembling Burkitt cells. Chromosomal analysis revealed a complex chromosomal karyotype, including t(14;18)(q32;q21), and FISH analysis confirmed split BCL2, BCL6, and MYC signals. Bone marrow biopsy revealed diffusely infiltrating large abnormal lymphoid cells with a CD10⁺, CD20⁺, BCL2⁺, BCL6⁺, c-MYC⁺ and MUM1(-) immunophenotype. B-cell lymphoma, unclassifiable with features intermediate between diffuse large B-cell lymphoma and BL, was diagnosed. The patient achieved a partial response after eight courses of DA-EPOCH-R chemotherapy. Our experience suggests that DA-EPOCH-R may be an effective treatment for DHL/THL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/genética , Translocação Genética , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Análise Citogenética , Proteínas de Ligação a DNA/genética , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Etoposídeo/administração & dosagem , Etoposídeo/uso terapêutico , Humanos , Linfoma de Células B/diagnóstico , Masculino , Prednisona/administração & dosagem , Prednisona/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-6 , Proteínas Proto-Oncogênicas c-myc/genética , Vincristina/administração & dosagem , Vincristina/uso terapêutico
13.
J Am Chem Soc ; 136(34): 12184-92, 2014 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-25127315

RESUMO

A hydrogen bond (H-bond) is one of the most fundamental and important noncovalent interactions in chemistry, biology, physics, and all other molecular sciences. Especially, the dynamics of a proton or a hydrogen atom in the H-bond has attracted increasing attention, because it plays a crucial role in (bio)chemical reactions and some physical properties, such as dielectricity and proton conductivity. Here we report unprecedented H-bond-dynamics-based switching of electrical conductivity and magnetism in a H-bonded purely organic conductor crystal, κ-D3(Cat-EDT-TTF)2 (abbreviated as κ-D). This novel crystal κ-D, a deuterated analogue of κ-H3(Cat-EDT-TTF)2 (abbreviated as κ-H), is composed only of a H-bonded molecular unit, in which two crystallographically equivalent catechol-fused ethylenedithiotetrathiafulvalene (Cat-EDT-TTF) skeletons with a +0.5 charge are linked by a symmetric anionic [O···D···O](-1)-type strong H-bond. Although the deuterated and parent hydrogen systems, κ-D and κ-H, are isostructural paramagnetic semiconductors with a dimer-Mott-type electronic structure at room temperature (space group: C2/c), only κ-D undergoes a phase transition at 185 K, to change to a nonmagnetic insulator with a charge-ordered electronic structure (space group: P1). The X-ray crystal structure analysis demonstrates that this dramatic switching of the electronic structure and physical properties originates from deuterium transfer or displacement within the H-bond accompanied by electron transfer between the Cat-EDT-TTF π-systems, proving that the H-bonded deuterium dynamics and the conducting TTF π-electron are cooperatively coupled. Furthermore, the reason why this unique phase transition occurs only in κ-D is qualitatively discussed in terms of the H/D isotope effect on the H-bond geometry and potential energy curve.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/química , Catecóis/química , Deutério/química , Condutividade Elétrica , Fenômenos Magnéticos , Semicondutores , Cristalização , Cristalografia por Raios X , Transporte de Elétrons , Ligação de Hidrogênio , Estrutura Molecular , Transição de Fase , Análise Espectral Raman
14.
Opt Lett ; 39(7): 1768-71, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24686600

RESUMO

We demonstrate second-harmonic generation (SHG) in a silicon-carbide (SiC)-based heterostructure photonic crystal nanocavity by using a pulsed laser. We observe SHG light radiated from the SiC nanocavity and estimate the conversion efficiency in the cavity to be 2.59×10(-5) (=0.15 W(-1)) at an average input power of 0.17 mW. The near-field patterns and polarization characteristics of the SHG light are investigated experimentally and theoretically, and the results are in qualitatively good agreement.


Assuntos
Compostos Inorgânicos de Carbono/química , Nanotecnologia , Fenômenos Ópticos , Fótons , Compostos de Silício/química , Lasers
15.
Anal Sci ; 40(6): 1043-1050, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38430367

RESUMO

To ensure maximum therapeutic safety and efficacy of stem cell transplantation, it is essential to observe the kinetics of behavior, accumulation, and engraftment of transplanted stem cells in vivo. However, it is difficult to detect transplanted stem cells with high sensitivity by conventional in vivo imaging technologies. To diagnose the kinetics of transplanted stem cells, we prepared multifunctional nanoparticles, Gd2O3 co-doped with Er3+ and Yb3+ (Gd2O3: Er, Yb-NPs), and developed an in vivo double modal imaging technique with near-infrared-II (NIR-II) fluorescence imaging and magnetic resonance imaging (MRI) of stem cells using Gd2O3: Er, Yb-NPs. Gd2O3: Er, Yb-NPs were transduced into adipose tissue-derived stem cells (ASCs) through a simple incubation process without cytotoxicity under certain concentrations of Gd2O3: Er, Yb-NPs and were found not to affect the morphology of ASCs. ASCs labeled with Gd2O3: Er, Yb-NPs were transplanted subcutaneously onto the backs of mice, and successfully imaged with good contrast using an in vivo NIR-II fluorescence imaging and MRI system. These data suggest that Gd2O3: Er, Yb-NPs may be useful for in vivo double modal imaging with NIR-II fluorescence imaging and MRI of transplanted stem cells.


Assuntos
Gadolínio , Imageamento por Ressonância Magnética , Células-Tronco , Gadolínio/química , Animais , Camundongos , Células-Tronco/citologia , Raios Infravermelhos , Transplante de Células-Tronco , Nanopartículas/química , Imagem Óptica , Elementos da Série dos Lantanídeos/química , Tecido Adiposo/citologia
16.
Int J Rheum Dis ; 27(1): e14942, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37828793

RESUMO

We describe the case of a 61-year-old woman with anti-signal recognition particle (SRP) antibody-positive immune-mediated necrotizing myopathy (IMNM) who exhibited biopsy-confirmed thrombotic microangiopathy (TMA). The patient developed proximal-dominant muscle weakness and was diagnosed with anti-SRP antibody-positive IMNM based on muscle biopsy results and serological examination. A high-dose corticosteroid prescription was initiated, followed by intravenous methylprednisolone and intravenous immunoglobulin therapy (IVIg). The patient showed IVIg-induced hemolytic anemia with preserved ADAMTS13 activity. Transient oral tacrolimus administration was initiated. Approximately 8 weeks after admission, the serum creatinine levels gradually increased. Renal histological examination revealed TMA, including ischemic changes in the renal tubules, stenosis, and occlusion of the interlobular arteries with fibrinoid necrosis of the afferent arteriolar walls. The arteriolar walls demonstrated an accumulation of C1q and C3c. Myofiber damage in patients with IMNM accounts for the activation of the classical pathway of the complement cascade in the sarcolemma due to antibody deposition. Additionally, a membrane attack complex is observed on capillaries in the muscle tissues of patients with anti-SRP antibody-positive IMNM. Although drug-induced pathomechanisms, such as IVIg and tacrolimus, can trigger the development of TMA, we suggest that the presence of serum anti-SRP antibodies would be implicated in complement-associated kidney vascular damage.


Assuntos
Doenças Autoimunes , Miosite , Microangiopatias Trombóticas , Feminino , Humanos , Pessoa de Meia-Idade , Imunoglobulinas Intravenosas/uso terapêutico , Músculo Esquelético/patologia , Partícula de Reconhecimento de Sinal , Tacrolimo , Autoanticorpos , Miosite/induzido quimicamente , Miosite/diagnóstico , Miosite/tratamento farmacológico , Microangiopatias Trombóticas/induzido quimicamente , Microangiopatias Trombóticas/diagnóstico , Microangiopatias Trombóticas/tratamento farmacológico
17.
IJU Case Rep ; 6(6): 394-397, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37928290

RESUMO

Introduction: Cholesterol crystal embolism is a rare microembolic disease caused by cholesterol crystals that can present with various symptoms after vascular surgery, catheterization, or anticoagulation therapy. We report a case of penile ulceration caused by cholesterol crystal embolism. Case presentation: A 72-year-old man undergoing maintenance dialysis for end-stage renal failure presented with penile pain and a black glans ulcer. Despite low-density lipoprotein apheresis, he was referred to our hospital because of lack of improvement. Based on his medical history and clinical presentation, including artificial vascular replacement and right toe amputation, cholesterol crystal embolism was suspected and partial penectomy was performed, thus confirming the diagnosis. Penile pain resolved after surgery, and he was discharged on Day 10. Unfortunately, he died after small bowel perforation developed 2 months after surgery. Conclusion: Penile ulcers caused by cholesterol crystal embolism may indicate the severity and progression of disease and typically require surgical intervention.

18.
Cell Transplant ; 32: 9636897231176442, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37226765

RESUMO

Stem cell therapy plays an important role in regenerative therapy; however, there is little information on the in vivo dynamics of transplanted stem cells and the influence of the inflammation of affected tissues or organs on these dynamics. In this study, we revealed real-time dynamics of transplanted adipose tissue-derived stem cells (ASCs) and the influence of the inflammatory states on these dynamics in acute liver failure mice. Quantum dots (QDs) labeling did not affect the cytokine profile of ASCs, and intravenously transplanted ASCs labeled with QDs could be detected in real time with high efficiency without laparotomy. Until 30 min after ASC transplantation, no marked differences in the behavior or accumulation of transplanted ASCs in the liver were observed among the three groups with different degrees of liver damage (normal, weak, and strong). However, significant differences in the engraftment rate of transplanted ASCs in the liver were observed among the three groups from 4 h after transplantation. The engraftment rate was inversely correlated with the extent of the liver damage. These data suggested that QDs are useful for in vivo real-time imaging of transplanted cells, and the inflammatory state of tissues or organs may affect the engraftment rate of transplanted cells.


Assuntos
Falência Hepática Aguda , Pontos Quânticos , Transplantes , Animais , Camundongos , Falência Hepática Aguda/terapia , Adipócitos , Células-Tronco
19.
Opt Express ; 20(14): 14789-96, 2012 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-22772174

RESUMO

We show that a SiC photonic crystal cannot only inhibit two photon absorption completely, but also suppress higher-order multiple photon absorption significantly at telecommunication wavelengths, compared to conventional Si-based photonic crystal nanocavities. Resonant spectra of a SiC nanocavity maintain a Lorentzian profile even at input energies 100 times higher than what can be applied to a Si nanocavity without causing nonlinear effects. Theoretical fitting of the results indicates that the four photon absorption coefficient in the SiC nanocavity is less than 2.0 × 10(-5) cm(5)/GW(3). These results will contribute to the development of high-power applications of SiC nanocavities such as harmonic generation, parametric down conversion, and Raman amplification.

20.
Biomimetics (Basel) ; 7(2)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35466257

RESUMO

Biological hydroxyapatite (HA) contains the different minor ions which favour its bio-reactivity in vivo. In this study, the preparation of HA particles containing both silicate and carbonate ions under the presence of sodium silicate was investigated, and the physicochemical properties were evaluated according to the contents and states of silicate and carbonate ions. The increment in the silicate ion reduced the crystallinity and expanded the crystalline size along with a-axis. Solid-state 29Si-NMR spectra indicated the increase in the adsorption of oligomeric silicate species on the HA particle surfaces in addition to the substitution state of silicate ions, suggesting the occurrence of the surface coating of silicates on the surfaces. The possible states of carbonate and silicate ions at the HA surfaces will provide the bioactivity.

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