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1.
Adv Ther ; 39(3): 1403-1416, 2022 03.
Article in English | MEDLINE | ID: mdl-35112307

ABSTRACT

INTRODUCTION: Anti-vascular endothelial growth factor (VEGF) therapy is the first-choice treatment for neovascular age-related macular degeneration (nvAMD); however, patients often are burdened physically, financially, and mentally. We investigated the relationship between mental status and feasibility of an intravitreal ranibizumab treat-and-extend (TAE) regimen for nvAMD. METHODS: In this prospective, multicenter study, 75 patients with nvAMD received ranibizumab intravitreally in a TAE regimen. After two monthly injections, the injection intervals were extended step-by-step to 6, 8, 12, and 16 weeks in eyes with dry maculas on optical coherence tomography (OCT) and, if exudation persisted or relapsed, shortened by one step. The best corrected visual acuity (BCVA) measurement and OCT were performed at baseline and on the same days of the scheduled injections. At baseline, all patients completed a survey, the Hospital Anxiety and Depression Scale (HADS), regarding mental burden. At week 52, patients on the TAE regimen for 1 year completed the HADS and a questionnaire designated to assess treatment-associated mental status. RESULTS: Fifty-one patients (68%) completed the 1-year TAE regimen; 24 eyes (32%) discontinued the TAE regimen because of the rescue treatment, difficulty in completing clinical visits, or financial burden. In 51 eyes on the TAE regimen for 1 year, the mean BCVAs improved from 64.3 letters at baseline to 71.6 letters at week 52. The mean anxiety and depression scores on HADS decreased significantly (p < 0.01) after the 1-year treatment. Women tended to have higher anxiety scores, possibly associated with fear of injection and recurrence, while some men had higher depression scores potentially associated with financial burden, difficulty in completing clinical visits, and subsequent interruption of the TAE regimen especially in eyes with low treatment efficacy. CONCLUSIONS: A TAE regimen of intravitreal ranibizumab injections preserves vision in eyes with nvAMD and reduces mental burden associated with disease relapse. TRIAL REGISTRATION: This clinical study was registered retrospectively on December 22, 2014 with the ClinicalTrials.gov identifier NCT02321839.


Subject(s)
Macular Degeneration , Wet Macular Degeneration , Angiogenesis Inhibitors/therapeutic use , Feasibility Studies , Female , Humans , Intravitreal Injections , Macular Degeneration/drug therapy , Male , Prospective Studies , Ranibizumab/therapeutic use , Receptors, Vascular Endothelial Growth Factor/therapeutic use , Retrospective Studies , Tomography, Optical Coherence/methods , Treatment Outcome , Visual Acuity , Wet Macular Degeneration/drug therapy
2.
Article in English | MEDLINE | ID: mdl-34769795

ABSTRACT

The novel coronavirus pandemic has resulted in an urgent need to study the risk of infection from aerosols generated during dental care and to conduct a review of infection controls. However, existing studies on aerosol particles related to dental treatment have mainly evaluated only the scattering range. Few studies have been conducted on the specifics of the generation of aerosol particles in clinical settings, their mechanisms and patterns of distribution throughout open or enclosed spaces, the duration that they remain suspended in air, and the amount and size of particles present. To minimize the influence of background particles, laser lights, a high-sensitivity camera, and particle counters were used in a large super clean laboratory to investigate the dynamics of aerosols generated during the operation of dental micromotors. The results indicate that aerosols tend to scatter upward immediately after generation and then gradually disperse into the surroundings. Most of the particles are less than 5 µm in size (only a few are larger), and all particles are widely distributed over the long term. Our research clearly elucidates that aerosols produced in dental care are distributed over a wide area and remain suspended for a considerable time in dental clinics before settling.


Subject(s)
COVID-19 , SARS-CoV-2 , Aerosols , Humans , Pandemics , Particle Size
3.
Phys Chem Chem Phys ; 23(13): 7724-7734, 2021 Apr 07.
Article in English | MEDLINE | ID: mdl-32870215

ABSTRACT

Two-dimensional hydrogen boride (HB) sheets were recently demonstrated to act as a solid acid catalyst in their hydrogen-deficient state. However, both the active sites and the mechanism of the catalytic process require further elucidation. In this study, we analyzed the conversion of ethanol adsorbed on HB sheets under vacuum during heating using in situ Fourier transform infrared (FT-IR) absorption spectroscopy with isotope labelling. Up to 450 K, the FT-IR peak associated with the OH group of the adsorbed ethanol molecule disappeared from the spectrum, which was attributed to a dehydration reaction with a hydrogen atom from the HB sheet, resulting in the formation of an ethyl species. At temperatures above 440 K, the number of BD bonds markedly increased in CD3CH2OH, compared to CH3CD2OH; the temperature dependence of the formation rate of BD bonds was similar to that of the dehydration reaction rate of ethanol on HB sheets under steady-state conditions. The rate-determining step of the dehydration of ethanol on HB was thus ascribed to the dehydrogenation of the methyl group of the ethyl species on the HB sheets, followed by the immediate desorption of ethylene. These results show that the catalytic ethanol dehydration process on HB involves the hydrogen atoms of the HB sheets. The obtained mechanistic insights are expected to promote the practical application of HB sheets as catalysts.

4.
Angew Chem Int Ed Engl ; 59(44): 19669-19674, 2020 Oct 26.
Article in English | MEDLINE | ID: mdl-32602591

ABSTRACT

Encapsulating metal nanoclusters into zeolites combines the superior catalytic activity of the nanoclusters with high stability and unique shape selectivity of the crystalline microporous materials. The preparation of such bifunctional catalysts, however, is often restricted by the mismatching in time scale between the fast formation of nanoclusters and the slow crystallization of zeolites. We herein demonstrate a novel strategy to overcome the mismatching issue, in which the crystallization of zeolites is expedited so as to synchronize it with the rapid formation of nanoclusters. The concept was demonstrated by confining Pt and Sn nanoclusters into a ZSM-5 (MFI) zeolite in the course of its crystallization, leading to an ultrafast, in situ encapsulation within just 5 min. The Pt/Sn-ZSM-5 exhibited exceptional activity and selectivity with stability in the dehydrogenation of propane to propene. This method of ultrafast encapsulation opens up a new avenue for designing and synthesizing composite zeolitic materials with structural and compositional complexity.

5.
J Am Chem Soc ; 142(8): 3931-3938, 2020 Feb 26.
Article in English | MEDLINE | ID: mdl-32017544

ABSTRACT

Improving the stability of porous materials for practical applications is highly challenging. Aluminosilicate zeolites are utilized for adsorptive and catalytic applications, wherein they are sometimes exposed to high-temperature steaming conditions (∼1000 °C). As the degradation of high-silica zeolites originates from the defect sites in their frameworks, feasible defect-healing methods are highly demanded. Herein, we propose a method for healing defects to create extremely stable high-silica zeolites. High-silica (SiO2/Al2O3 > 240) zeolites with *BEA-, MFI-, and MOR-type topologies could be stabilized by significantly reducing the number of defect sites via a liquid-mediated treatment without using additional silylating agents. Upon exposure to extremely high temperature (900-1150 °C) steam, the stabilized zeolites retain their crystallinity and micropore volume, whereas the parent commercial zeolites degrade completely. The proposed self-defect-healing method provides new insights into the migration of species through porous bodies and significantly advances the practical applicability of zeolites in severe environments.

6.
BMC Res Notes ; 13(1): 43, 2020 Jan 28.
Article in English | MEDLINE | ID: mdl-31992352

ABSTRACT

OBJECTIVES: The purposes of this study are to evaluate the interpersonal communication capabilities in basic nursing education and to develop an interpersonal communication skill scale with reference to microcounseling theory. RESULTS: A quantitative analytical design was employed that involved administering a 28-item self-efficacy survey with reference to microcounseling techniques to 208s-year female nursing students. Measurement data include the nursing student version of the communication skill preliminary scale draft, the generalized self-efficacy scale, and age. Criterion-related validity was verified through descriptive statistics, exploratory factor analysis, and correlation analysis. Factor analysis resulted in a 4-factor structure based on eigenvalues and scree plot. The reliability coefficient shows a correlation between the total score of each factor and the total score of the generalized self-efficacy scale at the 1% level. On the nursing student communication skill scale, the factor structure comprises four factors and 21 items; adjusting the items by confirming the contents of the question sentences realized the structure of the four factors, which show satisfactory reliability, and 20 scale items. Of these, 18 are classified according to microcounseling techniques. This study demonstrates the content and criterion-related validity of the scale.


Subject(s)
Communication , Social Skills , Students, Nursing , Factor Analysis, Statistical , Female , Humans , Self Efficacy , Young Adult
7.
Anal Sci ; 36(2): 177-181, 2020 Feb 10.
Article in English | MEDLINE | ID: mdl-31474660

ABSTRACT

Nanometer-sized clay, allophane, was used as the matrix for matrix-assisted laser desorption ionization mass spectrometry (MALDI MS) and applied to the ionization of small molecules. First, the laser desorption ionization mass spectrum of cation-exchanged allophane was measured, and it was found that the cation exchange proceeded smoothly with increasing atomic number of alkali metals in the periodic table. This phenomenon was explained by considering the size of the counter anion on the allophane surface. Then, fructose was measured as the analyte using each alkali-cation-exchanged allophane as the matrix. Contrary to the measurements using allophane itself, the peak intensity of fructose decreased with increasing atomic number of alkali metals in the periodic table. This phenomenon was clarified by considering the stability of alkali cation in the presence of a surface anion, the desorption energy, and the solvation enthalpy of each alkali cation. The applicability of allophane to high molecular weight compounds was also confirmed by measuring cyclodextrin, angiotensin II, and insulin. Finally, a combination of allophane and zeolite was examined by assuming proton relay among allophane, zeolite, and analyte. As a result of proton supply from zeolite to allophane, the peak intensity of the proton sponge (1,8-bis(dimethylamino)naphthalene) was enhanced by almost 2.2 times.

8.
ACS Omega ; 4(9): 14100-14104, 2019 Aug 27.
Article in English | MEDLINE | ID: mdl-31497729

ABSTRACT

Hydrogen boride (HB) or hydrogenated borophene sheets are recently realized two-dimensional materials that are composed of only two light elements, boron and hydrogen. However, their catalytic activity has not been experimentally analyzed. Herein, we report the catalytic activity of HB sheets in ethanol reforming. HB sheets catalyze the conversion of ethanol to ethylene and water above 493 K with high selectivity, independent of the contact time, and with an apparent activation energy of 102.8 ± 5.5 kJ/mol. Hence, we identify that HB sheets act as solid-acid catalysts.

9.
Chem Commun (Camb) ; 55(20): 2896-2899, 2019 Mar 05.
Article in English | MEDLINE | ID: mdl-30702094

ABSTRACT

The effect of reaction conditions for direct oxidation of methane to methanol over Fe-MFI zeolite with H2O2 has been investigated. Sulfolane has been proved to be an efficient solvent for liquid-phase methane oxidation. A sulfolane/water mixture with an appropriate proportion led to an extremely high methanol production with a high selectivity.

10.
Acta Crystallogr C Struct Chem ; 74(Pt 11): 1289-1294, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-30398181

ABSTRACT

Proton conduction in crystalline porous materials has received much attention from basic scientific research through to practical applications. Polyoxometalates (POMs) can efficiently transport protons because of their small superficial negative charge density. A simple method for enhancing proton conductivity is to introduce NH4+ into the crystal structure, because NH4+ can form hydrogen bonds and function as a proton carrier. According to these considerations, NH4+ was introduced into the porous structure of A2[Cr3O(OOCH)6(etpy)3]2[α-SiW12O40]·nH2O (A = Li, Na, K and Cs; etpy = 4-ethylpyridine) (I-A+) via topotactic cation exchange. The resulting compound, diammonium tris(4-ethylpyridine)hexaformatooxidotrichromium α-silicododecatungstate hexahydrate, (NH4)2[Cr3(CHO2)6O(C7H9N)3]2[α-SiW12O40]·6H2O, showed high proton conductivity and low activation energy under high relative humidity (RH), suggesting that protons migrate efficiently via rearrangement of the hydrogen-bonding network formed by the NH4+ cations and the waters of crystallization (Grotthuss mechanism). The proton conductivity and activation energy greatly decreased and increased, respectively, with the decrease in RH, suggesting that protons migrate as NH4+ and/or H3O+ under low RH (vehicle mechanism).

11.
Org Lett ; 20(18): 5569-5572, 2018 09 21.
Article in English | MEDLINE | ID: mdl-30199261

ABSTRACT

The use of diaminomethylenemalononitrile (DMM) organocatalyst to promote the challenging 1,2-hydrophosphonylation of simple ketones and enones, which are also called α,ß-unsaturated ketones, is proposed and validated. This reaction provided the corresponding chiral α-hydroxy phosphonates in high to excellent yields and with enantioselectivity up to 96% ee.

12.
Langmuir ; 34(4): 1376-1385, 2018 01 30.
Article in English | MEDLINE | ID: mdl-29293354

ABSTRACT

Carbon dioxide was shown to identify surface basic properties of nitrogen-substituted microporous and mesoporous silicas, in addition to conventional basic oxides, by a detailed study using isotherm and heat of adsorption measurements as well as by infrared spectroscopy. A hydrogen-bonded weak interaction was primarily observed between CO2 and silanol (Si-OH) and silamine (Si-NH-Si) groups. The heat of adsorption of CO2 demonstrated that the latter adspecies were formed preferentially over the former, although a much higher amount of linear CO2 adspecies were found on SBA-15 mesoporous silica because of the presence of a large quantity of silanol groups on its surface. Carbamate-type chemisorbed adspecies were not detected on silamino sites, whereas carbonate-type adspecies were formed on alkali ion-exchanged zeolites and also residual sodium ions on the surface of silicalite-1. CO2 was shown to be a successful probe molecule for identifying weakly interactive hydrogen-bonding sites, and it has potential as a surface probe for strongly interactive nucleophilic sites derived from alkaline ions or a methylated silamino group, Si-N(CH3)-Si.

13.
Phys Chem Chem Phys ; 19(43): 29077-29083, 2017 Nov 08.
Article in English | MEDLINE | ID: mdl-28936524

ABSTRACT

Proton conduction in alkali metal ion-exchanged porous ionic crystals A2[Cr3O(OOCH)6(etpy)3]2[α-SiW12O40]·nH2O [I-A+] (A = Li, Na, K, Cs, etpy = 4-ethylpyridine) is investigated. Single crystal and powder X-ray diffraction measurements show that I-A+ possesses analogous one-dimensional channels where alkali metal ions (A+) and water of crystallization exist. Impedance spectroscopy and water diffusion measurements of I-A+ show that proton conductivities are low (10-7-10-6 S cm-1) under low relative humidity (RH), and protons mostly migrate as H3O+ with H2O as vehicles (vehicle mechanism). The proton conductivity of I-A+ increases with the increase in RH and is largely dependent on the types of alkali metal ions. I-Li+ shows a high proton conductivity of 1.9 × 10-3 S cm-1 (323 K) and a low activation energy of 0.23 eV under RH 95%. Under high RH, alkali metal ions with high ionic potentials (e.g., Li+) form a dense and extensive hydrogen-bonding network of water molecules with mobile protons at the periphery, which leads to high proton conductivities and low activation energies via rearrangement of the hydrogen-bonding network (Grotthuss mechanism).

14.
Dalton Trans ; 46(10): 3105-3109, 2017 Mar 07.
Article in English | MEDLINE | ID: mdl-28074198

ABSTRACT

A porous ionic crystal is synthesized with a cationic Al(iii)-salphen complex (Al(iii)-salphen) and a α-Keggin-type polyoxometalate (POM). The compound possesses stable three dimensional porous structure and shows high activity as a heterogeneous catalyst in pinacol rearrangement, which is a typical acid reaction. Notably, Al(iii)-salphen, POM, and a physical mixture of the two components are much less active, suggesting a synergetic effect of Al(iii)-salphen and POM in a porous framework.

15.
ACS Macro Lett ; 6(7): 775-780, 2017 Jul 18.
Article in English | MEDLINE | ID: mdl-35650861

ABSTRACT

The synthesis of ladder polymers is still a big challenge in polymer chemistry, and in particular, there are few examples of conformationally flexible well-defined ladder polymers. Here we report an efficient and convenient route to conformationally flexible ladder polymers, which is based on a postpolymerization reaction of a rigid ladder polymer containing Tröger's base in its main chain. The postpolymerization reaction involves sequential N-methylation and hydrolysis for the Tröger's base unit, resulting in a diazacyclooctane skeleton that can exhibit a ring-flipping motion. Molecular dynamics simulations predicted that this motion provides conformational flexibility with the resultant ladder polymer, which was demonstrated by 1H NMR spectroscopy in solution. The presence of the diazacyclooctane units in the flexible ladder polymer allowed further functionalization through reactions involving its secondary amine moiety. The present synthetic method may lead to the development of a new class of ladder polymers that exhibit both conformational and design flexibility.

16.
Dalton Trans ; 45(7): 2805-9, 2016 Feb 21.
Article in English | MEDLINE | ID: mdl-26804446

ABSTRACT

A mesoporous ionic crystal is synthesized with a polyoxometalate and a macrocation with polar cyano groups. The compound possesses one-dimensional mesopores with an opening of 3.0 × 2.0 nm. The compound shows high proton conductivity and catalytic activity, which are due to the water molecules in the mesopores.

17.
J Phys Chem Lett ; 6(12): 2243-6, 2015 Jun 18.
Article in English | MEDLINE | ID: mdl-26266598

ABSTRACT

The reaction mechanism of the decomposition of ethoxy species to ethene and acidic OH groups on H-ZSM-5 was studied by IR spectroscopy using isotope-labeled ethanol. The concerted mechanism occurring on both the ethoxy (acid) site and the counterpart lattice oxygen was suggested by GC-MS analysis of evolved d2-ethene and IR observation of the recovery of OH s groups on acid sites from the decomposition of CH3CD2O- ethoxy species. The concerted mechanism was further confirmed by the estimation of activation energy for decomposition of CH3CH2O-, CH3CD2O-, and CD3CD2O- ethoxy species, 122 ± 3, 125 ± 3, and 140 ± 5 kJ mol(-1), respectively, where the kinetic isotope effect was observed for the cleavage of the CH or CD bond of the methyl group of the ethoxy species.

18.
ChemSusChem ; 8(15): 2476-80, 2015 Aug 10.
Article in English | MEDLINE | ID: mdl-26073555

ABSTRACT

Titanium(IV) incorporated into the framework of molecular sieves can be used as a highly active and sustainable catalyst for the oxidation of industrially important organic molecules. Unfortunately, the current process for the incorporation of titanium(IV) requires a large amount of expensive organic molecules used as organic-structure-directing agents (OSDAs), and this significantly increases the production costs and causes environmental problems owing to the removal of OSDAs by pyrolysis. Herein, an OSDA-free process was developed to incorporate titanium(IV) into BEA-type molecular sieves for the first time. More importantly, the hydrophobic environment and the robust, 3 D, and large pore structure of the titanium(IV)-incorporated molecular sieves fabricated from the OSDA-free process created a catalyst that was extremely active and selective for the epoxidation of bulky cyclooctene in comparison to Ti-incorporated BEA-type molecular sieves synthesized with OSDAs and commercial titanosilicate TS-1.


Subject(s)
Silicates/chemistry , Titanium/chemistry , Catalysis , Hydrogen Peroxide/chemistry , Hydrophobic and Hydrophilic Interactions , Microscopy, Electron, Scanning , Oxidants/chemistry , Oxidation-Reduction , X-Ray Diffraction
19.
Microscopy (Oxf) ; 63(4): 313-24, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24948708

ABSTRACT

Tantalum oxynitrides with various nitrogen contents were synthesized from Ta2O5 powder by nitridation under a flow of ammonia at 1123 K for various durations. X-ray powder diffraction, transmission electron microscopy, Ultraviolet-visible spectroscopy, energy-dispersive spectroscopy, elemental analysis and photocatalytic reaction were performed to investigate these samples. Selected-area electron diffraction analysis of the mixed crystalline phases of powder samples revealed that each particle had only one crystalline phase. This indicates that entire particles underwent a rapid structural transformation once their nitrogen content reached a critical value. We discovered a new intermediate crystalline phase of tantalum oxynitride, TaO(a > 1)N(b <1), appeared before the generation of the ß-TaON phase. The crystal structure of TaO(a > 1)N(b <1) is suggested to be monoclinic, with unit cell parameters of a = 5.1 Å, b = 35.6 Å, c = 5.4 Å and ß = 93.5°. The ratio of nitrogen to oxygen in the samples increased with increasing nitridation duration. The increasing rate is different in the different nitridation stage due to the different structure of the samples. Nitrogen entered the samples quickly during the initial 5 h of nitridation, and a monoclinic ß-TaON phase was formed. A mesoporous structure emerged in the nitrided particles during the phase transition, greatly increasing the surface area of the samples. The more the nitrogen entered one sample, the darker the color of it due to the narrower the band gap. H2 and O2 evolved by water splitting from the nitrided samples irradiated with visible light. Change in the evolution rate of H2 and O2 had a relation with the structure of the samples.

20.
Phys Chem Chem Phys ; 16(9): 4155-64, 2014 Mar 07.
Article in English | MEDLINE | ID: mdl-24451998

ABSTRACT

In addition to the original preparation route of the RTH-type zeolites using 1,2,2,6,6-pentamethylpiperidine (PMP) as an organic structure directing agent (OSDA), we have found that simpler organic amines such as N-methylpiperidine and pyridine can be used as alternative OSDAs in place of PMP. Furthermore, we have established a synthesis method for preparing the RTH-type zeolites without using any OSDAs. In this study, RTH-type aluminosilicates were synthesized with different types of OSDA or without using any OSDAs. The obtained zeolites synthesized with different preparation methods were characterized by using various techniques, especially high-resolution (27)Al MAS NMR and in situ FT-IR techniques using CO adsorption. The relationship between the preparation method and the catalytic performance in the methanol to olefins (MTO) reaction was discussed. Finally, the distribution of Al species in the RTH-framework was clarified.

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