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1.
J Clin Microbiol ; 58(2)2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31748320

RESUMO

There are several convenient and accurate molecular assays to detect respiratory bacterial infection. The NeoPlex RB-8 detection kit (NeoPlex RB-8) is a new multiplex real-time PCR assay that simultaneously detects Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila, Haemophilus influenzae, Bordetella pertussis, Bordetella parapertussis, and Moraxella catarrhalis in a single test. This study compared the clinical concordance of NeoPlex RB-8 with another method, Seeplex PneumoBacter ACE detection assay (Seeplex PB ACE), which simultaneously detects S. pneumoniae, M. pneumoniae, C. pneumoniae, L. pneumophila, H. influenzae, and B. pertussis We tested 2,137 nasopharyngeal swab and sputum specimens using both assays. For discordant Bordetella parapertussis and M. catarrhalis specimens, we also performed bidirectional sequencing. For S. pneumoniae, M. pneumoniae, C. pneumoniae, L. pneumophila, H. influenzae, and B. pertussis, which are detected by both NeoPlex RB-8 and Seeplex PB ACE, the positive and negative agreement between the two assays ranged from 91.7 to 100% (κ = 0.918 to 1). S. pneumoniae and H. influenzae were the most discordant targets and measured with higher sensitivity and specificity by NeoPlex RB-8 than Seeplex PB ACE. For Bordetella parapertussis and M. catarrhalis, which are not detected by Seeplex PB ACE, NeoPlex RB-8 sensitivity and specificity were >99%. Overall, NeoPlex RB-8 was highly comparable to Seeplex PB ACE, but NeoPlex RB-8 was more clinically accurate, with higher throughput and more convenience.


Assuntos
Bactérias/classificação , Infecções Bacterianas/diagnóstico , Reação em Cadeia da Polimerase Multiplex/normas , Kit de Reagentes para Diagnóstico/normas , Infecções Respiratórias/microbiologia , Bactérias/patogenicidade , Infecções Bacterianas/microbiologia , Humanos , Reação em Cadeia da Polimerase Multiplex/métodos , Nasofaringe/microbiologia , Infecções Respiratórias/diagnóstico , Sensibilidade e Especificidade , Escarro/microbiologia
2.
J Nanosci Nanotechnol ; 19(2): 1204-1207, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30360235

RESUMO

Pure and lead-doped SrTiO3 perovskite type oxides were successfully synthesized by sol-gel method and characterized by XRD, SEM and DRS. From the results of XRD, the metal replacement with the Pb ion on the crystal lattice does not change the high crystallinity of the perovskite structure. UV-vis DRS analysis shows that Pb was in situ doped in the lattice of SrTiO3 and the absorption band shifted to a higher wavelength on the Pb-doped SrTiO3 sample compared to the pure SrTiO3 sample. We also investigated the photocatalytic activity of Pb-doped SrTiO3 for the decomposition of Rhodamine B under visible light irradiation. From the results of photocatalytic decomposition of RhB, a doping of lead into SrTiO3 perovskite oxides enhanced the photocatalytic activity under visible light irradiation.

3.
J Nanosci Nanotechnol ; 17(4): 2690-694, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-29664582

RESUMO

A solvothermal method assisted by microwave technique has been developed for the synthesis of highly crystalline and monoclinic BiVO4 powders with ellipsoidal structure, using Bi(NO3)3 · 5H2O and Na3VO4 · 12H2O as raw materials, and oleic acid as surfactant. The phase structure and morphology of as-prepared BiVO4 samples were characterized by XRD, SEM and DRS. We have also investigated the photocatalytic activity of these materials for the decomposition of Rhodamine B under visible light irradiation. From DRS results, BiVO4 samples showed the absorption spectrum up to the visible region and then their photocatalytic activity was shown higher than commercial P-25 TiO2 materials. BiVO4 prepared by the microwave-assisted solvothermal method showed highest photocatalytic activity due to a small particle-size effect.

4.
J Nanosci Nanotechnol ; 17(4): 2751-755, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29664597

RESUMO

Lead molybdate (PbMoO4) materials were successfully synthesized using a facile surfactant-assisted microwave process and characterized by XRD, Raman, PL, BET and DRS. We also investigated the photocatalytic activity of these materials for the decomposition of Rhodamine B under UV-light irradiation. The XRD and Raman results revealed the successful synthesis of 42­69 nm, well-crystallized PbMoO4 crystals with a facile surfactant-assisted microwave process. The PbMoO4 catalysts prepared using microwave process enhanced the photocatalytic activity compared to PbMoO4 catalyst prepared by hydrothermal method. The PbMoO4 catalyst prepared at 100 °C showed the highest photocatalytic activity. The PL peak was appeared at about 540 nm for all catalysts and the excitonic PL signal was proportional to the photocatalytic activity for the decomposition of Rhodamine B.

5.
J Nanosci Nanotechnol ; 16(2): 1911-5, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27433699

RESUMO

In this study, TiO2 and metal ion-doped TiO2 nanoparticles were successfully synthesized by solvothermal reaction of titanium butoxide precursor in the presence of oleic acid, oleylamine and vapor water and they were characterized by XRD, Raman, TEM and DRS. We also investigated the photocatalytic activity of these oxides for the decomposition of Rhodamine B. From XRD and Raman results, doping of the metal ion in the crystal lattice did not change the high crystallinity of the TiO2 structure, and all the metal ions were incorporated into the structures of titania as well as replaced titanium ion or located at interstitial site. The absorption band shifted to a higher wavelength on the metal ion-doped TiO2 samples compared to the pure TiO2 sample. The Ce ion- doped TiO2 catalysts showed the higher photocatalytic activity compared to the pure TiO2 and a commercial P-25 catalysts and 1% Ce-doped TiO2 showed the highest photocatalytic activity.


Assuntos
Luz , Nanopartículas/química , Processos Fotoquímicos , Titânio/química , Catálise
6.
J Nanosci Nanotechnol ; 15(7): 5450-4, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26373158

RESUMO

Iron-based MIL-53 crystals with uniform size were successfully synthesized using a microwave-assisted solvothermal method and characterized by XRD, FE-SEM and DRS. We also investigated the photocatalytic activity of MIL-53(Fe) for the decomposition of methylene blue using H2O2 as an electron acceptor. From XRD and SEM results, the fully crystallized MIL-53(Fe) materials were obtained regardless of preparation method. From DRS results, MIL-53(Fe) samples prepared using microwave-assisted process displayed the absorption spectrum up to the visible region and then they showed the high photocatalytic activity under visible light irradiation. The MIL-53(Fe) catalyst prepared by two times microwave irradiation showed the highest activity.


Assuntos
Ferro/química , Luz , Azul de Metileno/química , Micro-Ondas , Processos Fotoquímicos , Catálise
7.
J Nanosci Nanotechnol ; 15(1): 290-4, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26328347

RESUMO

Succinic acid (SA) produced from hydrogenation of maleic anhydride (MAN) is used widely in manufacturing of pharmaceuticals, agrochemicals, surfactants and detergent, green solvent and biodegradable plastic. In this study, we performed that liquid hydrogenation of MAN to SA with 5 wt% Pd supported on activated carbon (Pd/C) at low pressure and temperature. The synthesis of SA was performed in aqueous solution while varying temperature, pressure, catalytic amount and agitation speed. We confirmed that the composition of the products consisting of SA, maleic acid (MA), fumaric acid (FA) and malic acid (MLA) depends on the process. The catalytic characteristics were analyzed by TGA, TEM.


Assuntos
Carbono/química , Anidridos Maleicos/química , Anidridos Maleicos/metabolismo , Paládio/química , Técnicas de Química Sintética , Química Verde , Hidrogenação , Pressão , Ácido Succínico/química , Ácido Succínico/metabolismo , Temperatura
8.
J Nanosci Nanotechnol ; 15(1): 656-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26328420

RESUMO

Cu-Zn-Al catalysts were prepared using microwave-assisted process and co-precipitation methods. The prepared catalysts were characterized by XRD, BET, XPS and TPD of ammonia and their catalytic activity for the hydrogenolysis of glycerol to propylene glycol was also examined. The XRD patterns of Cu/Zn/Al mixed catalysts show CuO and ZnO crystalline phase regardless of preparation method. The highest glycerol hydrogenolysis conversion is obtained with the catalyst having a Cu/Zn/Al ratio of 2:2:1. Hydrogen pre-reduction of catalysts significantly enhanced both glycerol conversions and selectivity to propylene glycol. The glycerol conversion increased with an increase of reaction temperature. However, the selectivity to propylene glycol increased with an increase of temperature, and then declined to 30.5% at 523 K.


Assuntos
Glicerol/química , Metais Pesados/química , Nanoestruturas/química , Propilenoglicol/química , Catálise , Técnicas de Química Sintética , Temperatura Alta , Hidrogênio , Micro-Ondas , Tamanho da Partícula , Difração de Raios X
9.
J Nanosci Nanotechnol ; 14(11): 8507-11, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25958554

RESUMO

Catalytic combustion of benzene over CuO-CeO2 mixed oxides has been investigated. The CuO-CeO2 mixed oxides were prepared by the combustion method using malic acid as an organic fuel and characterized by XRD, XPS and TPR. For the CuO-CeO2 catalyst with a Cu/(Cu + Ce) molar ratio of more than 0.4, highly dispersed copper oxide species were shown at 2θ = 35.5 degrees and 38.8 degrees. The CuO-CeO2 catalyst prepared using 2.0 M malic acid showed the highest activity, with conversion reaching nearly 100% at 350 degrees C. In addition, the highest activity is shown on Cu0.40 (the index denotes the molar ratio Cu/(Cu + Ce)) sample and then it decreases on Cu0.5 and Cu0.7 samples.


Assuntos
Benzeno/química , Césio/química , Cobre/química , Óxidos/química , Benzeno/análise , Catálise , Malatos/química , Nanopartículas Metálicas/química , Temperatura
10.
J Nanosci Nanotechnol ; 14(11): 8502-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25958553

RESUMO

Lead molybdate (PbMoO4) was successfully synthesized using a microwave-assisted method and characterized by XRD, Raman spectroscopy, SEM, PL and DRS. We also investigated the photocatalytic activity of these materials for the decomposition of Rhodamin B under UV-light irradiation. The XRD and Raman results revealed the successful synthesis of 42-52 nm, well-crystallized PbMoO4 crystals with the microwave-assisted hydrothermal method. The PbMoO4 catalysts prepared using the microwave-assisted process enhanced the photocatalytic activity compared to that prepared by hydrothermal method and the catalysts prepared at a solution pH = 11 and temperature of 105 degrees C showed the highest photocatalytic activity. The PL peaks appeared at about 540 nm for all catalysts and the excitonic PL signal was proportional to the photocatalytic activity for the decomposition of Rhodamin B.


Assuntos
Chumbo/química , Nanopartículas Metálicas/química , Molibdênio/química , Óxidos/química , Micro-Ondas , Nanotecnologia , Tamanho da Partícula , Processos Fotoquímicos , Rodaminas/análise , Rodaminas/química
11.
J Nanosci Nanotechnol ; 13(11): 7707-11, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24245319

RESUMO

A facile approach was employed for the preparation of stable luminescent nanocomposites of CdS quantum dots (QDs) and polyacrylamide (PAM) through the cross coupling chemistry. Initially, CdS QDs were synthesized in a well controlled manner using 3-mercaptopropionic acid as a capping agent. Then, carboxylic acid groups on CdS QDs were chemically incorporated into PAM matrices with the assistance of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride and N-hydroxysulfosuccinimide coupling agents. FT-IR analysis was used to investigate the chemical incorporation of CdS QDs in PAM matrices via the covalent protocol. The XPS elemental mapping studies further suggested the formation of CdS-PAM nanocomposites. FE-SEM and TEM images were engaged to study the morphologies, and distribution of CdS QDs in the PAM networks. The physical structure of the CdS-PAM nanocomposites was investigated by XRD analysis. Thermal stability of the nanocomposites was observed to be enhanced in compare to PAM as evidenced from TGA data. The UV-vis and photoluminescence studies of the CdS-PAM nanocomposites suggested their promising optical applications.


Assuntos
Resinas Acrílicas/química , Compostos de Cádmio/síntese química , Cristalização/métodos , Luminescência , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Pontos Quânticos , Compostos de Selênio/síntese química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Refratometria , Propriedades de Superfície , Condutividade Térmica
12.
J Nanosci Nanotechnol ; 13(3): 2320-4, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23755686

RESUMO

In this study, we have investigated the photocatalytic activity for the decomposition of methyl orange on the LaCoO3 perovskite-type oxides prepared using sol-gel method at different conditions. From the results of UV-Vis DRS, all the catalysts have the similar absorption spectrum up to visible region. The LaCoO3 catalyst prepared at 1.5 mol of malic acid and calcined at 350 degrees C shows the highest activity. The amount of photo absorption in the visible region is correlated with the photocatalytic activity. In addition, the chemisorbed oxygen plays an important role on the photocatalytic decomposition of methyl orange and the higher are the contents of chemisorbed oxygen, the better shows the performance of photocatalyst.

13.
J Nanosci Nanotechnol ; 13(11): 7439-43, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24245270

RESUMO

Noncovalent functionalization of graphene was carried out via in-situ oxidative polymerization of poly(3-octylthiophene) (P3OT). First, graphene sheets were prepared by a modified Hummer's method and subsequently reduced with hydrazine monohydrate. The structure and morphology of the composites were investigated by using FTIR, XPS, EDX, TGA, HRTEM, FESEM and XRD measuments. The results obtained from spectroscopic studies confirm the reduction of graphite oxide to graphene. UV-Vis and photoluminescence spectroscopies were also used to prove the doping function of the graphene in the composites. Dispersion stability indicates the good mixing between graphene and the polymer due to pi-pi interaction between two components. Scanning electron microscopy results suggest that the graphene sheets were well dispersed in the polymer matrix. The UV-Vis spectra of graphene/P3OT composites show a red shift by a few nanometers, while the emission spectra show a small blue shift. However, the nanocomposites retained the photoluminescence property of as synthesized P3OT.


Assuntos
Cristalização/métodos , Grafite/química , Medições Luminescentes/métodos , Membranas Artificiais , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Polímeros/química , Tiofenos/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
14.
J Nanosci Nanotechnol ; 13(9): 6120-4, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24205612

RESUMO

In this study, LaMnO3 perovskite type oxides were successfully prepared using the malic acid method. The oxides were characterized by TG/DTA, XRD, XPS, TEM and H2-TPR and their catalytic activities for the combustion of benzene were determined. Almost all of the catalysts showed perovskite crystalline phase and had a particle size of 15-60 nm. The LaMnO3 catalysts prepared with more than 1.0 mol of malic acid showed the highest activity and the conversion reached almost 100% at 310 degrees C. The catalysts were modified to enhance the activity by substituting the metal at the A or B site of the perovskite oxides. In the LaMnO3-type catalyst, the partial substitution of Sr into site A enhanced the catalytic activity during benzene combustion. In addition, the partial substitution of Co into site B also increased the catalytic activity and the catalytic activity was in the following order: Co > Cu > Fe in the LaMn1_xBxO3(B = Co, Fe, Cu) type catalysts.

15.
J Nanosci Nanotechnol ; 13(9): 6160-4, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24205620

RESUMO

In this study, nanosized lead-substituted perovskite type oxides, La1_xPbxCoO3, were successfully synthesized using a microwave-assisted method and characterized by TG/DTA, XRD, XPS, TEM and DRS. We also investigated the photocatalytic activity of these oxides for the decomposition of methyl orange. From XRD results, metal replacement with the Pb ion in the crystal lattice does not change the high crystallinity of the perovskite structure. When Pb ions are substituted into site A, the particle size decreased when compared to lead-free LaCoO3 perovskite type oxide. In the of UV-Vis DRS analysis, all the catalysts displayed the similar absorption spectrum up to the visible region and the absorption band shifted to a higher wavelength on the lead-substituted LaCoO3 perovskite oxides when compared to the lead-free LaCoO3 oxide. From XPS results, chemisorbed oxygen was shown to play an important role in the photocatalytic decomposition of methyl orange and the higher chemisorbed oxygen content, the better the performance of the photocatalyst.

16.
J Nanosci Nanotechnol ; 13(3): 1970-3, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23755631

RESUMO

A series of poly(methylmethacrylate-co-2-hydroxyethylmethacrylate)/polyhedral oligomeric silsesquioxanes (P(MMA-co-HEMA)/POSS) nanocomposites were synthesized by the combination of ATRP and click chemistry. The hybrid nanocomposites were characterized by FT-IR, 1H-NMR, GPC, SEM, XRD, DSC, and TGA analyses. The loading of POSS in the nanocomposites was calculated using 1H-NMR data. TGA measurements suggested that the incorporation of POSS into polymer matrices enhanced decomposition temperature as well as char yield of the polymeric materials. The glass transition temperature linearly increased with the increase of POSS loading plausibly because of the aggregation of POSS nanoparticles and the dipole-dipole interaction between POSS and P(MMA-co-HEMA) segments.

17.
Pain Physician ; 26(3): E203-E211, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37192243

RESUMO

BACKGROUND: Although several studies have examined the epidemiological features of vertebral compression fractures (VCF) among elderly patients, few studies have reported the epidemiology of VCF among younger individuals. OBJECTIVE: To examine trends in the incidence and mortality of VCF in both the old (>= 65 years) and young (< 65 years) age groups. This study aimed to investigate the incidence and mortality of VCF among all age groups in Korea. STUDY DESIGN: Population-based cohort study. SETTING: A nationwide, population-based setting. METHODS: Using the Korean National Health Insurance database, which has complete population coverage, we identified patients diagnosed with VCF between 2005 to 2018. Differences in incidence, survival and mortality were compared across groups using Kaplan-Meier analysis and Cox regression for all age groups and both genders. RESULTS: We identified a total of 742,993 VCF patients and the annual incidence was 140.09/100,000 individuals. Although the incidence of VCF was significantly higher in the older age compared to younger age group (556.38/100,000 vs. 44.09/100,000 individuals), the mortality rate ratio for VCF patients was higher among younger compared to older individuals (old: 1.59 vs. young: 2.87). In our multivariable-adjusted analysis, the hazard ratio for multiple fractures, traumatic injury and osteoporosis were higher in patients aged < 65 years compared to patients aged >= 65 years, suggesting that the impact of these clinical variables on mortality is more significant in the younger age group. LIMITATION: A limitation of this study was its lack of information on clinical features, such as disease severity and laboratory data. The precise cause of death of VCF patients could not be confirmed from the study database. CONCLUSIONS: The mortality rate ratio and hazard ratio were significantly higher among younger patients with VCF, indicating the need for further research on VCF in younger age groups.


Assuntos
Fraturas por Compressão , Osteoporose , Fraturas da Coluna Vertebral , Idoso , Humanos , Masculino , Feminino , Fraturas por Compressão/epidemiologia , Estudos de Coortes , Incidência , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Osteoporose/complicações , República da Coreia/epidemiologia
18.
J Nanosci Nanotechnol ; 12(5): 4384-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22852413

RESUMO

Fabrication of a hybrid consists of gold nanoparticles and multi walled carbon nanotubes (MWCNTs) with the help of poly (amino acid) was investigated. Poly(acryloyl beta-alanine) was synthesized by precipitation polymerization in tetrahydrofuran. The polymers were used to form hybrids with MWCNTs in aqueous media. Subsequently, the polymer functionalized MWCNTs were fabricated by in situ formed gold nanoparticles. The fabrication by gold nanoparticles was confirmed by transmission electron microscopic analyses. The fabrication was attempted with different concentrations of lithium auric chloride solutions in the range of 0.1-1.2 mM in water. The lower concentration of the gold precursor solution resulted in the formation and attachment of gold nanoparticles without aggregation while the higher concentration above 1.0 mM led to the aggregation of gold nanoparticles. The gold nanoparticles were observed only on the surface of MWCNTs and none was in the bulk aqueous phase.

19.
J Nanosci Nanotechnol ; 12(1): 840-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22524067

RESUMO

Water-soluble polymer brushes with multi-walled carbon nanotubes (MWNTs) as backbones were synthesized by grafting 2-hydroxyethyl methacrylate (HEMA) from surface functionalized MWNTs via in situ surface thiol-lactam initiated radical polymerization. MWNTs were functionalized with 2-mercaptoethanol and used as initiators in the polymerization of HEMA in the presence of butyrolactam. FT-IR, XPS, 1H NMR, GPC and TGA were used to determine chemical structure and the grafted polymer quantities of the resulting product. The covalent bonding of PHEMA to the MWNTs dramatically improved the water dispersibility of MWNTs. The average thicknesses of the polymer brushes in the functionalized MWNTs were detected with electron microscopy (SEM and TEM) and images indicated that the nanotubes were coated with polymer layer.


Assuntos
Cristalização/métodos , Lactamas/química , Metacrilatos/química , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Titânio/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Polímeros/química , Compostos de Sulfidrila/química , Propriedades de Superfície
20.
J Nanosci Nanotechnol ; 11(1): 833-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21446556

RESUMO

SBA-15 mesoporous materials were successfully prepared by the conventional hydrothermal method and used as the support for TiO2 loaded SBA-15 photocatalysts. The synthesized materials were characterized by XRD, PL, FT-IR, BET and TEM. We also examined the activity of these materials as photocatalysts for the decomposition of methylene blue. The loading of titanium dioxide on the framework of SBA-15 makes the pore diameter and the pore volume decrease and decreases the surface area compared to that of SBA-15. For the TiO2 loaded SBA-15 photocatalysts, the IR absorption at approximately 960 cm(-1) is commonly accepted as the characteristic vibration of the Ti-O-Si bond. The PL peaks appears at about 410 nm at a loading ratio of less than 5% but moves to 430 nm at higher loading ratios. It was also shown that the excitonic PL signal is proportional to the photocatalytic activity for the decomposition of methylene blue. The photocatalytic activity increases with increasing TiO2 loading ratio, shows a maximum value at 7% TiO2/SBA-15, and then decreases at 10% TiO2/SBA-15.

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