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1.
Artículo en Inglés | MEDLINE | ID: mdl-36767924

RESUMEN

The purpose of this study is to verify the influence of the relationship between risk perception of COVID-19 and the war-applied Model of Goal-directed Behavior (MGB) based on stimulus-organism-response (SOR) and potential travelers' behavioral intention. In addition, this study attempted to verify the relationship among uncertainty toward international travel, mental well-being toward international travel, and desire toward travelers' behavioral intention. Moreover, we examined the moderating effect of gender (female vs. male) among all variables for dependents. The survey was conducted on potential travelers in Korea. As for the survey period, a survey was conducted for one month beginning on 2 September 2022. Of the total 413 surveys, 361 surveys were used for the final analysis, and 52 unfaithful surveys were excluded. In addition, demographic, CFA, correlation analysis, structural equation modeling, and moderation effect analysis were verified using SPSS and AMOS. For the data analysis, we used SPSS 18.0 and Amos 20.0 to perform factor analysis and SEM. Significant effects were found in support for Hypotheses 1-5. Further, when it comes to the difference of gender on the relationship between all the variables, while no significant effect was found for Hypotheses 6a,c,e,g, a significant effect was found for Hypotheses 6b,d,f. Thus, H6a,c,e were rejected and H6b,d,f were supported. It was found that females had a greater influence on mental health and desire for overseas travel than males, but it was found that there was no difference between females and males in the relationship between desire and behavioral intention. Therefore, it was possible to verify that the MGB desire is an important psychological variable for both females and males. Furthermore, these findings offer academic practical implications to travel and tourism companies by presenting basic data based on the results of empirical research analysis in the context of the current dangerous situation.


Asunto(s)
COVID-19 , Intención , Masculino , Humanos , Femenino , COVID-19/epidemiología , Objetivos , Viaje/psicología , Percepción
2.
J Control Release ; 352: 994-1008, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36370877

RESUMEN

Wireless powered optogenetic cell-based implant provides a strategy to deliver subcutaneously therapeutic proteins. Immortalize Human Mesenchymal Stem Cells (hMSC-TERT) expressing the bacteriophytochrome diguanylate cyclase (DGCL) were validated for optogenetic controlled interferon-ß delivery (Optoferon cells) in a bioelectronic cell-based implant. Optoferon cells transcriptomic profiling was used to elaborate an in-silico model of the recombinant interferon-ß production. Wireless optoelectronic device integration was developed using additive manufacturing and injection molding. Implant cell-based optoelectronic interface manufacturing was established to integrate industrial flexible compact low-resistance screen-printed Near Field Communication (NFC) coil antenna. Optogenetic cell-based implant biocompatibility, and device performances were evaluated in the Experimental Autoimmune Encephalomyelitis (EAE) mouse model of multiple sclerosis.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Ratones , Animales , Humanos , Esclerosis Múltiple/terapia , Encefalomielitis Autoinmune Experimental/terapia , Interferón beta/genética , Interferón beta/metabolismo , Modelos Animales de Enfermedad , Expresión Génica , Ratones Endogámicos C57BL
3.
Artículo en Inglés | MEDLINE | ID: mdl-36012075

RESUMEN

The goal of this study is to investigate the influence relationship between AMO applied green HRM and employees' green OCB. This study also attempted to verify the relationship between employees' green OCB and green performance management. Specifically, we tried to define the effects of green awareness and green psychological climate on green HRM and green OCB. Moreover, we examined the mediating effect of green CSR perception on the relationship between green OCB and green performance management. To do so, we surveyed Rooms and F&B employees from nine global chain hotels in South Korea that actively contribute to a green package. An "actively contributing hotel" is one that has leadership in energy and environmental design certification. Further, employees of such hotels consider them proenvironmental hotels. For data analysis, we carried out SEM and factor analysis using SPSS 18.0 and Amos 20.0 (IBM, Armonk, NY, USA). All hypotheses were adopted as having significantly positive (+) effects. Hypotheses 4, 7, and 11 predicted partial mediating effects. The findings of the study have significant theoretical and practical ramifications for corporate environmental strategic performance management. Specifically, this study identified the relationship between the mediation variables on green OCB and green PM, as demonstrated in previous studies. Additionally, these results provide an effective employee management strategy for the green HRM of green hotels by providing concrete data. First, green hotels need to raise employees' green awareness and green psychological climate to increase their green OCB. Second, employees themselves ultimately have to enhance the green CSR perception to raise green PM.


Asunto(s)
Liderazgo , Organizaciones , Humanos , República de Corea , Encuestas y Cuestionarios
4.
Artículo en Inglés | MEDLINE | ID: mdl-35682378

RESUMEN

We investigated the relationship between green consciousness and green behavior, and the relationship between psychological state, attitude, and behavior of green hotel customers by applying variables suitable for an expanded theory of planned behavior. The purpose of the study was to predict green behavior based on the theory of planned behavior. Together with preceding research including the correlation between customers' image perception of green corporate social responsibility (CSR), green psychological benefit, and green consciousness, we added willingness to sacrifice for the environment to define the relationship with green consciousness and green behavior. A survey was conducted with 410 customers of green hotels in Seoul, Korea more than twice over a period of over 6~12 months. Vague and insincere answers were removed. SPSS 18.0 and Amos 20.0 were used to conduct factor and SEM data analysis. Our theory was verified and adopted following validation from our analysis. The results have important theoretical and practical implications for the environment by providing primary data on customers' perceptions of eco friendliness to support the establishment of corporate management strategies. Moreover, they may encourage green hotels to participate in preventing environmental problems.


Asunto(s)
Estado de Conciencia , Intención , Actitud , Teoría Psicológica , República de Corea , Encuestas y Cuestionarios
5.
Sensors (Basel) ; 21(19)2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34640703

RESUMEN

This study proposes the development of a wireless sensor system integrated with smart ultra-high performance concrete (UHPC) for sensing and transmitting changes in stress and damage occurrence in real-time. The smart UHPC, which has the self-sensing ability, comprises steel fibers, fine steel slag aggregates (FSSAs), and multiwall carbon nanotubes (MWCNTs) as functional fillers. The proposed wireless sensing system used a low-cost microcontroller unit (MCU) and two-probe resistance sensing circuit to capture change in electrical resistance of self-sensing UHPC due to external stress. For wireless transmission, the developed wireless sensing system used Bluetooth low energy (BLE) beacon for low-power and multi-channel data transmission. For experimental validation of the proposed smart UHPC, two types of specimens for tensile and compression tests were fabricated. In the laboratory test, using a universal testing machine, the change in electrical resistivity was measured and compared with a reference DC resistance meter. The proposed wireless sensing system showed decreased electrical resistance under compressive and tensile load. The fractional change in resistivity (FCR) was monitored at 39.2% under the maximum compressive stress and 12.35% per crack under the maximum compressive stress tension. The electrical resistance changes in both compression and tension showed similar behavior, measured by a DC meter and validated the developed integration of wireless sensing system and smart UHPC.

6.
J Environ Biol ; 36(6): 1247-54, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26688957

RESUMEN

In the present study, esterified rice bran oil (ERBO) was characterized using enzymatic esterification to improve stability, prevent acidification, enhance health-promoting biological activity and generate ω-3 PUFA-rich rice bran oil (RBO). Esterification reactions using RBO and ethanol were performed at 50°C under 200 bar with 3% lipozyme TL-IM (Thermomuces lanuginosa immobilized on silica gel) or RM-IM (Rhizomucor miehei immobilized on ion exchange resin) for 3 hr under supercritical CO2. The molar ratios of ethanol to RBO were 3, 6, 9 and 12, respectively. Total lipid contents and acid values decreased (maximum 83.75%),but γ-oryzanol content increased (maximum 41.33%) in esterified RBO (ERBO) prepared using TL-IM or RM-IM. In addition, DPPH radical scavenging activity of ERBO prepared by RM-IM atan ethanol to RBO molar ratio of 3 was 0.02 µg µl(-1), which was 63-fold higher than that of α-tocopherol (IC50 =1.25 µg µl(-1)). The anti-inflammatory effect of RM-IM 1:3 hydrolysate of RBO was verified showing its suppressive effect towards iNOS and Cox-2mRNA expression in a dose-dependent manner. Therefore, ERBO is a promising source of functional food, cosmetics and pharmaceuticals.


Asunto(s)
Aceites de Plantas/química , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antioxidantes/química , Compuestos de Bifenilo , Línea Celular , Esterificación , Macrófagos/efectos de los fármacos , Ratones , Picratos , Aceites de Plantas/toxicidad , Aceite de Salvado de Arroz
7.
Metab Eng ; 29: 169-179, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25843350

RESUMEN

Cyclic guanosine monophosphate (cGMP) is a universal second messenger that is synthesized from guanosine triphosphate (GTP) by guanylyl cyclases (GCs) and hydrolyzed into guanosine monophosphate (GMP) by phosphodiesterases (PDEs). Small-molecule drugs that induce high cGMP levels in specialized tissues by boosting GC activity or inhibiting PDE activity have become the predominant treatment strategy for a wide range of medical conditions, including congestive heart failure, pulmonary hypertension, atherosclerosis-based claudication and erectile dysfunction. By fusing the cGMP receptor protein (CRP) of Rhodospirillum centenum to the Herpes simplex-derived transactivation domain VP16, we created a novel synthetic mammalian cGMP-sensing transcription factor (GTA) that activates synthetic promoters (PGTA) containing newly identified GTA-specific operator sites in a concentration-dependent manner. In cell lines expressing endogenous natriuretic peptide receptor A (NPR-A) (HeLa), GTA/PGTA-driven transgene expression was induced by B-type natriuretic peptide (BNP; Nesiritide(®)) in a concentration-dependent manner, which activated NPR-A׳s intracellular GC domain and triggered a corresponding cGMP surge. Ectopic expression of NPR-A in NPR-A-negative cell lines (HEK-293T) produced high cGMP levels and mediated maximum GTA/PGTA-driven transgene expression, which was suppressed by co-expression of PDEs (PDE-3A, PDE-5A and PDE-9A) and was re-triggered by the corresponding PDE inhibitor drugs (Pletal(®), Perfan(®), Primacor(®) (PDE-3A), Viagra(®), Levitra(®), Cialis(®) (PDE-5A) and BAY73-6691 (PDE-9A)). Mice implanted with microencapsulated designer cells co-expressing the GTA/PGTA device with NPR-A and PDE-5A showed control of blood SEAP levels through administration of sildenafil (Viagra(®)). Designer cells engineered for PDE inhibitor-modulated transgene expression may provide a cell-based PDE-targeting drug discovery platform and enable drug-adjusted gene- and cell-based therapies.


Asunto(s)
Proteínas Bacterianas , Proteínas Portadoras , GMP Cíclico/metabolismo , Regulación de la Expresión Génica , Péptidos y Proteínas de Señalización Intracelular , Rhodospirillum centenum/genética , Citrato de Sildenafil/farmacología , Animales , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/genética , Proteínas Portadoras/biosíntesis , Proteínas Portadoras/genética , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Células HEK293 , Células HeLa , Humanos , Péptidos y Proteínas de Señalización Intracelular/biosíntesis , Péptidos y Proteínas de Señalización Intracelular/genética , Ratones
8.
Angew Chem Int Ed Engl ; 54(20): 5933-8, 2015 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-25788334

RESUMEN

Precise spatiotemporal control of physiological processes by optogenetic devices inspired by synthetic biology may provide novel treatment opportunities for gene- and cell-based therapies. An erectile optogenetic stimulator (EROS), a synthetic designer guanylate cyclase producing a blue-light-inducible surge of the second messenger cyclic guanosine monophosphate (cGMP) in mammalian cells, enabled blue-light-dependent penile erection associated with occasional ejaculation after illumination of EROS-transfected corpus cavernosum in male rats. Photostimulated short-circuiting of complex psychological, neural, vascular, and endocrine factors to stimulate penile erection in the absence of sexual arousal may foster novel advances in the treatment of erectile dysfunction.


Asunto(s)
Luz , Optogenética/métodos , Erección Peniana/efectos de los fármacos , Animales , GMP Cíclico/biosíntesis , GMP Cíclico/metabolismo , Disfunción Eréctil/tratamiento farmacológico , Guanilato Ciclasa/metabolismo , Masculino , Ratas
9.
Biol Pharm Bull ; 37(12): 1963-70, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25451845

RESUMEN

Rice bran oil extracted by supercritical CO2 extraction (RB-SCE) reportedly exhibits pharmacological activities such as antioxidant and in vivo hair growth-inducing effects. Such activities raise the possibility of the development of novel hair growth-inducing agents using RB-SCE. The aim of this study was to investigate the potential genotoxic effects of RB-SCE in three short-term mutagenicity assays (bacterial reverse mutation assay, in vitro mammalian chromosomal aberration test, and in vivo micronucleus assay). RB-SCE showed no genotoxicity in the bacterial reverse mutation assay up to 5000 mg/plate and in the in vivo micronucleus test up to 600 mg/kg body weight. However, at 120 µg/mL with S9 mix and 200 µg/mL without S9 mix RB-SCE showed significantly different genotoxicity than the negative control in the in vitro chromosome aberration test. The induction of chromosomal aberrations under the present conditions may have no biological significance. We have herein demonstrated that RB-SCE can be regarded as a non-genotoxic material based on the available in vivo and in vitro results.


Asunto(s)
Dióxido de Carbono/química , Cromatografía con Fluido Supercrítico/métodos , Aberraciones Cromosómicas/inducido químicamente , Aceites de Plantas/química , Aceites de Plantas/toxicidad , Animales , Línea Celular , Cricetinae , Relación Dosis-Respuesta a Droga , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Fibroblastos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos ICR , Pruebas de Micronúcleos , Aceite de Salvado de Arroz , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Organismos Libres de Patógenos Específicos
10.
J Biotechnol ; 162(2-3): 237-45, 2012 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-23036923

RESUMEN

Although magnetic fields and paramagnetic inorganic materials were abundant on planet earth during the entire evolution of living species the interaction of organisms with these physical forces remains a little-understood phenomenon. Interestingly, rather than being genetically encoded, organisms seem to accumulate and take advantage of inorganic nanoparticles to sense or react to magnetic fields. Using a synthetic biology-inspired approach we have genetically programmed mammalian cells to show superparamagnetic behavior. The combination of ectopic production of the human ferritin heavy chain 1 (hFTH1), engineering the cells for expression of an iron importer, the divalent metal ion transferase 1 (DMT1) and the design of an iron-loading culture medium to maximize cellular iron uptake enabled efficient iron mineralization in intracellular ferritin particles and conferred superparamagnetic behavior to the entire cell. When captured by a magnetic field the superparamagnetic cells reached attraction velocities of up to 30 µm/s and could be efficiently separated from complex cell mixtures using standard magnetic cell separation equipment. Technology that enables magnetic separation of genetically programmed superparamagnetic cells in the absence of inorganic particles could foster novel opportunities in diagnostics and cell-based therapies.


Asunto(s)
Separación Celular/métodos , Ferritinas/metabolismo , Ingeniería Genética/métodos , Magnetismo/métodos , Proteínas de Transporte de Catión/química , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo , Supervivencia Celular , Medios de Cultivo/química , Ferritinas/química , Ferritinas/genética , Células HEK293 , Humanos , Espacio Intracelular , Hierro/metabolismo , Campos Magnéticos , Oxidorreductasas , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Reproducibilidad de los Resultados , Biología Sintética/métodos
11.
Water Res ; 41(17): 3977-88, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17631378

RESUMEN

Rejection of trace organic compounds, including disinfection by-products (DBPs) and pharmaceutical active compounds (PhACs), by high-pressure membranes has become a focus of public interest internationally in both drinking water treatment and wastewater reclamation/reuse. The ability to simulate, or even predict, the rejection of these compounds by high-pressure membranes, encompassing nanofiltration (NF) and reverse osmosis (RO), will improve process economics and expand membrane applications. The objective of this research is to develop a membrane transport model to account for diffusive and convective contributions to solute transport and rejection. After completion of cross-flow tests and diffusion cell tests with target compounds, modeling efforts were performed in accordance with a non-equilibrium thermodynamic transport equation. Comparing the percentages of convection and diffusion contributions to transport, convection is dominant for most compounds, but diffusion is important for more hydrophobic non-polar compounds. Convection is also more dominant for looser membranes (i.e., NF). In addition, higher initial compound concentrations and greater J(0)/k ratios contribute to solute fluxes more dominated by convection. Given the treatment objective of compound rejection, compound transport and rejection trends are inversely related.


Asunto(s)
Membranas Artificiales , Modelos Químicos , Nanotecnología/métodos , Compuestos Orgánicos/química , Ultrafiltración/métodos , Purificación del Agua/métodos , Convección , Difusión , Cinética , Ósmosis
12.
J Am Chem Soc ; 128(33): 10658-9, 2006 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-16910642

RESUMEN

Ni/NiO core/shell nanoparticles having high affinity with polyhistidine were synthesized by decomposition of a Ni surfactant complex followed by air oxidation. Ni/NiO nanoparticles showed selective and efficient binding to histidine-tagged proteins and easy separation by using a magnet. These provided a more convenient way to efficient purification of histidine-tagged proteins compared with the conventional Ni-NTA complex-bound resins and microbeads.


Asunto(s)
Histidina/química , Nanopartículas del Metal/química , Níquel/química , Proteínas/química , Magnetismo , Unión Proteica
13.
Water Environ Res ; 77(1): 40-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15765934

RESUMEN

The rejection of emerging trace organics by a variety of commercial reverse osmosis (RO), nanofiltration (NF), and ultra-low-pressure RO (ULPRO) membranes was investigated using TFC-HR, NF-90, NF-200, TFC-SR2, and XLE spiral membrane elements (Koch Membrane Systems, Wilmington, Massachusetts) to simulate operational conditions for drinking-water treatment and wastewater reclamation. In general, the presence of effluent organic matter (EfOM) improved the rejection of ionic organics by tight NF and RO membranes, as compared to a type-II water matrix (adjusted by ionic strength and hardness), likely as a result of a decreased negatively charged membrane surface. Rejection of ionic pharmaceutical residues and pesticides exceeded 95% by NF-90, XLE, and TFC-HR membranes and was above 89% for the NF-200 membrane. Hydrophobic nonionic compounds, such as bromoform and chloroform, exhibited a high initial rejection, as a result of both hydrophobic-hydrophobic solute-membrane interactions and steric exclusion, but rejection decreased significantly after 10 hours of operation because of partitioning of solutes through the membranes. This resulted in a partial removal of disinfection byproducts by the RO membrane TFC-HR. In a type-II water matrix, the effect of increasing feed water recoveries on rejection of hydrophilic ionic and nonionic compounds was compound-dependent and not consistent for different membranes. The presence of EfOM, however, could neutralize the effect of hydrodynamic operating condition on rejection performance. The ULPRO and tight NF membranes were operated at lower feed pressure, as compared to the TFC-HR, and provided a product water quality similar to a conventional RO membrane, regarding trace organics of interest.


Asunto(s)
Preparaciones Farmacéuticas/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Desinfección , Filtración , Nanotecnología , Ósmosis , Presión
14.
Hepatol Res ; 29(2): 113-121, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15163433

RESUMEN

Liver cirrhosis accompanies at least 70% of hepatocellular carcinomas world-wide. To evaluate the dysregulation of apoptosis and the MAPK pathway in hepatocarcinogenesis, we investigated the expression profiles of the genes involved in apoptosis and MAPK pathway in cirrhosis and hepatocellular carcinoma. A total of 94 tissue specimens (61 cirrhosis and 33 hepatocellular carcinoma) obtained from 67 patients were analyzed by microarray, quantitative PCR and Western blot experiments. Of 71 apoptosis-associated genes, c-raf-1 and S6 were up-regulated in 42.9% and 32.1% of 28 cirrhosis tissues, respectively, and both genes were well correlated in a five-cluster K-means analysis. For c-raf-1 and down stream genes in the MAPK pathway, c-raf-1, MEK, and MAPK were up-regulated in 40%, 80%, and 86.7% of 45 cirrhosis specimens, respectively, and in 50%, 63.6%, and 59.1% of 22 hepatocellular carcinoma specimens, respectively. Western blot analysis showed that activated Raf-1 was over-expressed in 91.2% (52/57) of cirrhosis and in 100% (30/30) of hepatocellular carcinoma. The expression level of Raf-1 in 14 of 26 paired samples (53.8%) was significantly higher in hepatocellular carcinoma than in cirrhosis ( [Formula: see text] -fold, [Formula: see text] ). These results suggest that the activation of Raf-1 plays an important role in the development of hepatocellular carcinoma.

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