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1.
Inorg Chem ; 62(31): 12573-12581, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37498117

RESUMO

In the present study, we fabricated hollow cubic CuxO nanoparticles (∼23 nm) incorporated with CNF (HC-CuxO/CNF) through controlled thermal oxidation of solid cubic Cu2O nanoparticles (∼21 nm) supported on carbon nanofibers (SC-Cu2O/CNF) under airflow, exploiting the nanoscale Kirkendall effect. These hollow CuxO nanocubes with increased surface areas exhibited outstanding catalytic activity for unsymmetrical chalcogenide synthesis under ligand-free conditions.

2.
Nanomaterials (Basel) ; 13(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36839027

RESUMO

Highly dispersed Pt-incorporated mesoporous Fe2O3 (Pt/m-Fe2O3) of 4 µm size is prepared through a simple hydrothermal reaction and thermal decomposition procedures. Furthermore, the formaldehyde gas-sensing properties of Pt/m-Fe2O3 are investigated. Compared with our previous mesoporous Fe2O3-based gas sensors, a gas sensor based on 0.2% Pt/m-Fe2O3 shows improved gas response by over 90% in detecting low-level formaldehyde gas at 50 ppb concentration, an enhanced selectivity of formaldehyde gas, and a lower degradation of sensing performance in high-humidity environments. Additionally, the gas sensor exhibits similar properties as the previous sensor, such as operating temperature (275 °C) and long-term stability. The enhancement in formaldehyde gas-sensing performance is attributed to the attractive catalytic chemical sensitization of highly dispersed Pt nanoparticles in the mesoporous Fe2O3 microcube architecture.

3.
RSC Adv ; 12(38): 24998-25005, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36199886

RESUMO

Copper oxide nanoparticles (CuO NPs) with a clean surface supported on carbon nanofibers (CNFs) in one-pot were prepared by simple solid-state grinding and aging followed by thermal treatment, yielding CuO nanoparticles with high (23.8 wt%) and uniform CuO loading in the absence of surfactants and solvent. The CuO NPs on CNFs (CuO/CNF) showed excellent catalytic activity in transforming a wide variety of alkynes into alkenyl boronates using B2Pin2 as a boron source in the absence of ligand and additives with high regioselectivity under mild conditions. Moreover, the present CuO/CNF catalyst was recyclable and possesses excellent chemoselectivity. The developed green synthetic approach is expected to offer exciting opportunities for designing monometallic or bimetallic nanoparticle catalysts on different supports applied in heterogeneous catalysis.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31973063

RESUMO

Several studies have confirmed that the natural environment has psychophysiological healing effects. However, few studies have investigated the healing process involved in the effect of the natural environment. To date, no theoretical model on the nature-based therapy process has been clearly established. Thus, the aim of this study was to develop a theoretical model of the nature-based therapy process by analyzing individual empirical data. Research materials were 180 self-reported essays on "Forest Therapy Experiences" submitted to the Korea Forest Service. This study was conducted based on grounded theory. Data were analyzed through open coding. A total of 82 concepts, 21 subcategories, and six categories were derived. Results revealed that the nature-based therapy process contained six categories: Stimulation, acceptance, purification, insight, recharging, and change. When in the natural environment, participants first experienced positive emotional change, followed by cognitive and behavioral changes. Based on these results, a nature-based therapy process model was derived. This study revealed that the nature-based therapy process did not consist of just a single element or step, but involved an integrated way of healing with emotional and cognitive changes. This study is significant in that it derives a theoretical model of the nature-based therapy process with comprehensive mechanisms. Further research is needed to establish more systematic theoretical model.


Assuntos
Meio Ambiente , Teoria Fundamentada , Cura Mental , Humanos , República da Coreia
5.
Epidemiol Health ; 41: e2019027, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31208191

RESUMO

OBJECTIVES: Most children and adolescents have low levels of cancer knowledge and awareness, and infrequently engage in preventive behaviors. This study examined the effects of a short classroom-based intervention for cancer prevention on knowledge, attitude toward cancer preventability, self-efficacy, and behavioral intentions of fifth-grade elementary school students. METHODS: The study was based on a pre-post-follow-up, 2-group, quasi-experimental design. Participants in the intervention group attended two 40-minute sessions on cancer prevention education and watched a music video about cancer prevention, while participants in the control group were only exposed to the music video. Self-reported knowledge, attitude toward cancer preventability, self-efficacy, and behavioral intentions were assessed 1 week pre-intervention and post-intervention, as well as 3 months post-intervention. RESULTS: The 3-month post-intervention results revealed partial effects, indicating that the education intervention improved knowledge and attitudes toward cancer preventability; however, no effects were observed on self-efficacy and behavioral intentions 3 months after the intervention. CONCLUSIONS: Long-term regular booster sessions are required to improve not only social-cognitive factors, but also behavioral intentions, which could result in behavior changes promoting cancer prevention.


Assuntos
Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Intenção , Neoplasias/prevenção & controle , Autoeficácia , Estudantes/psicologia , Criança , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , República da Coreia , Instituições Acadêmicas , Estudantes/estatística & dados numéricos
6.
Chem Commun (Camb) ; 54(44): 5570-5573, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29761820

RESUMO

A pinhole-free BiVO4 electrode was successfully synthesized using an ultrasonic-assisted synthetic method on a conductive substrate. The pinhole-free BiVO4 electrode showed highly improved photoelectrochemical activity for both sulfite oxidation and water oxidation. The blocking recombination processes were examined to clarify the enhanced photoelectrochemical performances.

7.
J Nanosci Nanotechnol ; 18(2): 1356-1360, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448591

RESUMO

Hollow nanomaterials have attracted great interest because of their many applications in catalysis, nanoreactors, drug delivery systems, for lubrication and in gas sensors. Here, carbon sphere templates were prepared from glucose under hydrothermal conditions to facilitate the synthesis of hollow Fe2O3 nanospheres. Thermal decomposition of an iron precursor in benzylalcohol with the carbon spheres resulted in the deposition of Fe3O4 nanoparticles on the carbon sphere templates. The nanoparticles on the carbon surface naturally agglomerate and form a dense oxide shell during the calcination step, which produces typical Fe2O3 hollow structures. The gas sensing performance of the hollow Fe2O3 nanospheres was investigated at an operating temperature of 300 °C. The hollow Fe2O3 nanospheres showed high sensitivity (R = 10.766 at 1 ppm formaldehyde) with a linear response to formaldehyde gas concentration in the range of 0.8~2.4 ppm, and good selectivity to formaldehyde gas in volatile organic compounds, compared to commercial Fe2O3 nanoparticles.

8.
Epidemiol Health ; 39: e2017057, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29228522

RESUMO

OBJECTIVES: This study aimed to identify the characteristics of social networking service (SNS) users and to assess the relationship of those factors to user satisfaction with the SNSs of the National Cancer Information Center (NCIC) in South Korea. METHODS: A Web-based survey was completed by 1,670 users of the NCIC SNSs, who provided data on the sources they consulted for information about cancer, determinants of SNS use, sources of NCIC SNS awareness, the time of day they used the SNS, and their satisfaction level. RESULTS: Facebook users mainly became aware of the NCIC SNSs through an acquaintance's recommendation, while Twitter was accessed through other SNSs or blogs. Users in their 30s were less satisfied with the NCIC SNSs than those in their teens and 20s. Browsing for cancer-related information on the Internet, prioritizing information quality, and engaging in active use were related to a high level of satisfaction with the NCIC SNSs. Individuals who were exposed to the NCIC SNSs through other SNSs or printed materials were less satisfied with their experience of the NCIC SNSs than those who received a recommendation from an acquaintance. CONCLUSIONS: These findings may act as a catalyst to guide public health agencies to enhance their use of SNSs.


Assuntos
Informação de Saúde ao Consumidor , Centros de Informação , Neoplasias , Satisfação Pessoal , Rede Social , Adolescente , Adulto , Fatores Etários , Criança , Feminino , Humanos , Comportamento de Busca de Informação , Internet/estatística & dados numéricos , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , República da Coreia , Inquéritos e Questionários , Adulto Jovem
9.
Chem Commun (Camb) ; 53(24): 3454-3457, 2017 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-28266665

RESUMO

A self-assembled Ni(cyclam)-BTC film was formed on ITO in an acidic solution. Ni(cyclam)-BTC exhibited an enhanced electro-catalytic property for the oxygen evolution reaction (OER), which was strongly relevant to the Ni(iii)/Ni(iv) redox reaction activated by the potential dynamic process. A possible formation mechanism of Ni(cyclam)-BTC by self-assembly on ITO was also proposed.

10.
Chem Commun (Camb) ; 53(29): 4120-4123, 2017 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-28349133

RESUMO

The addition of water initiates the phase transition of hexagonal CoO to Co(OH)2 nanocrystals. Inducing the phase transition of h-CoO on various substrates results in efficient chemical bonding between Co(OH)2 and the substrate. The efficient deposition of Co(OH)2 is widely applicable for electrochemical and photoelectrochemical water oxidation reactions.

11.
J Nanosci Nanotechnol ; 16(2): 1863-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27433689

RESUMO

Carbon spheres have been prepared from glucose under hydrothermal conditions to facilitate the synthesis of hollow manganese oxides. The phases of manganese oxide are controlled by changing annealing temperature of the manganese monoxide on a carbon sphere template. The particles on the carbon surface get an agglomeration and make dense oxide shell during the calcination step, which result in typical hollow structures. The electrochemical properties of hollow manganese oxides have been investigated to elucidate their relative catalytic activities.

12.
Epidemiol Health ; 37: e2015030, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26212505

RESUMO

OBJECTIVES: Little attention has been paid to levels of trust in online sources of health information. The objective of this study was to investigate levels of trust in various sources of health information (interpersonal channels, traditional media, and Internet media), and to examine the predictors of trust in health information available on the Internet. METHODS: A questionnaire was administered to 1,300 people (20 years of age or older), evaluating levels of trust in various sources of health information. RESULTS: The highest level of trust was expressed regarding interpersonal channels, with hospital physicians regarded as the most trusted source of information age and income showed an association with trust in online information sources. Elderly people were not likely to trust Internet news sources, and high incomes were found to be strongly associated with trust in online sources of information overall. CONCLUSIONS: Public health organizations must consider the predictors for trust in various sources of information in order to employ appropriate media when targeting vulnerable individuals or developing messaging strategies for health professionals.

13.
Eur J Pharm Biopharm ; 95(Pt B): 398-406, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26036448

RESUMO

In this work, we tested the hypothesis that particles injected into the suprachoroidal space can be localized at the site of injection or broadly distributed throughout the suprachoroidal space by controlling polymeric formulation properties. Single hollow microneedles were inserted into the sclera of New Zealand White rabbits and injected non-biodegradable fluorescently tagged nanoparticles and microparticles suspended in polymeric formulations into the suprachoroidal space of the eye. When formulated in saline, the particles were distributed over 29-42% of the suprachoroidal space immediately after injection. To spread particles over larger areas of the choroidal surface, addition of hyaluronic acid to make moderately non-Newtonian solutions increased particle spread to up to 100% of the suprachoroidal space. To localize particles at the site of injection adjacent to the ciliary body, strongly non-Newtonian polymer solutions localized particles to 8.3-20% of the suprachoroidal space, which exhibited a small increase in area over the course of two months. This study demonstrates targeted particle delivery within the suprachoroidal space using polymer formulations that spread particles over the whole choroidal surface or localized them adjacent to the ciliary body after injection.


Assuntos
Corioide/metabolismo , Corpo Ciliar/metabolismo , Sistemas de Liberação de Medicamentos , Polímeros/química , Animais , Química Farmacêutica/métodos , Ácido Hialurônico/química , Microesferas , Nanopartículas , Agulhas , Coelhos , Esclera/metabolismo , Fatores de Tempo
14.
Ann Nutr Metab ; 56(2): 83-90, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20090312

RESUMO

BACKGROUND/AIMS: This study investigated the effects of dietary folic acid on the expression of myelin basic protein (MBP) in the maternal brain and spinal cord during pregnancy and lactation. METHODS: Female Sprague-Dawley rats were fed either a folic-acid-supplemented diet (FS, 8 mg/kg diet) or a folic-acid-deficient diet (FD, 0 mg/kg diet) from 2 weeks prior to mating until the end of lactation. The expressions of MBP were analyzed using Western blot analysis and immunohistochemistry, and myelin oligodendrocyte glycoprotein (MOG), and neuronal nuclear antigen by immunohistochemistry. RESULTS: The cerebrocortical expression of MBP was 87% higher at day 20 of pregnancy than before pregnancy in FS animals (p < 0.05) but did not change significantly in FD animals. No significant change was observed in the hippocampus or spinal cord in either dietary treatment group. The cerebrocortical MOG and NeuN expressions were significantly lower in FD animals than in FS animals before pregnancy and increased at day 20 of pregnancy but did not differ with the dietary folic acid level. CONCLUSIONS: Folic acid deficiency did not increase the expression level of MBP in the cerebral cortex during pregnancy, suggesting that folate intake during pregnancy plays an important role in the maintenance of myelin.


Assuntos
Encéfalo/metabolismo , Suplementos Nutricionais , Ácido Fólico/farmacologia , Lactação/metabolismo , Proteína Básica da Mielina/metabolismo , Gravidez/metabolismo , Medula Espinal/metabolismo , Animais , Antígenos Nucleares/efeitos dos fármacos , Antígenos Nucleares/metabolismo , Western Blotting/métodos , Encéfalo/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Dieta/métodos , Feminino , Deficiência de Ácido Fólico/metabolismo , Lactação/efeitos dos fármacos , Modelos Animais , Proteína Básica da Mielina/efeitos dos fármacos , Proteínas da Mielina , Glicoproteína Associada a Mielina/efeitos dos fármacos , Glicoproteína Associada a Mielina/metabolismo , Glicoproteína Mielina-Oligodendrócito , Ratos , Ratos Sprague-Dawley , Medula Espinal/efeitos dos fármacos , Complexo Vitamínico B/farmacologia
15.
Transgenic Res ; 13(6): 541-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15672835

RESUMO

Erythropoietin (EPO) is a glycoprotein used for curing human anemia by regulating the differentiation of erythroid progenitors and the production of red blood cells. To examine the expression of recombinant EPO in plants, pPEV-EP21, in which human epo cDNA under the control of the CaMV 35S promoter, was introduced into tobacco and Arabidopsis via Agrobacterium tumefaciens-mediated transformation. The RNA expression level of epo in the transgenic lines was initially estimated by Northern blot analysis. Two transgenic lines, which exhibited a high expression level of epo mRNA determined by Northern analysis, were chosen for Western blot analysis to examine the production of EPO proteins. Those two lines, EP21-12 and EP21-14, revealed detectable bands on the immunoblot. Interestingly, constitutive expression of the human epo gene affected the morphologies in transgenic plants such that vegetative growth of transgenic tobacco was retarded, and male sterility was induced in transgenic tobacco and Arabidopsis.


Assuntos
Arabidopsis/genética , Eritropoetina/metabolismo , Nicotiana/crescimento & desenvolvimento , Nicotiana/genética , Plantas Geneticamente Modificadas , Agrobacterium tumefaciens/genética , Western Blotting , Eritropoetina/genética , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/genética , Masculino , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , RNA Mensageiro , Proteínas Recombinantes/metabolismo , Transformação Genética
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