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211.
Multi-functionalized carbon nanomaterials have attracted interest owing to their excellent synergic properties, such as plasmon resonance energy transfer and surface-enhanced Raman scattering. Particularly, nanoparticle (NP)-decorated graphene (GRP) has been applied in various fields. In this study, silver NP (AgNP)- and magnetic iron oxide NP (IONP)-decorated GRP were prepared and utilized as biosensing platforms. In this case, AgNPs and GRP exhibit plasmonic properties, whereas IONPs exhibit magnetic properties; therefore, this hybrid nanomaterial could function as a magnetoplasmonic substrate for the magnetofluoro-immunosensing (MFI) system. Conversely, exosomes were recently considered high-potential biomarkers for the diagnosis of diseases. However, exosome diagnostic use requires complex isolation and purification methods. Nevertheless, we successfully detected a prostate-cancer-cell-derived exosome (PC-exosome) from non-purified exosomes in a culture media sample using Ag/IO-GRP and dye-tetraspanin antibodies (Ab). First, the anti-prostate-specific antigen was immobilized on the Ag/IO-GRP and it could isolate the PC-exosome from the sample via an external magnetic force. Dye-tetraspanin Ab was added to the sample to induce the sandwich structure. Based on the number of exosomes, the fluorescence intensity from the dye varied and the system exhibited highly sensitive and selective performance. Consequently, these hybrid materials exhibited excellent potential for biosensing platforms.  相似文献   
212.

Novel green-emitting phosphors K2Zn1???xP2O7: x mol% Mn2+ have been successfully prepared using classical solid-state reaction method in air atmosphere, doped by different Mn2+ ion contents, namely x?=?0.5, 1, 1.25 and 1.5 mol%. The samples were characterized by the thermogravimetric (ATD/ATG/DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), steady and time-resolved photoluminescence techniques. It was found that all K2Zn1???xP2O7: x mol% Mn2+ samples crystallize in the tetragonal phase with P42/mnm space group. Upon 425 nm excitation, K2ZnP2O7: Mn2+ exhibits an intense broad green asymmetric emission band peaking at 520 nm, owing to the 4T16A1(6 S) transition of Mn2+ ion in K2ZnP2O7. In addition, it is suggested that Mn2+ ions occupy more than one symmetry site in the host K2ZnP2O7. The optimal Mn2+ ion concentration in K2ZnP2O7:Mn2+ phosphor is 1 mol % and with the lifetime 9.81 ms.

  相似文献   
213.
Journal of Mechanical Science and Technology - Phosphoric acid fuel cells (PAFCs) are appropriate for applications that require high-quality power because of their high reliability. We propose a...  相似文献   
214.
Adiponectin, an adipose tissue-derived hormone, plays integral roles in lipid and glucose metabolism in peripheral tissues, such as the skeletal muscle, adipose tissue, and liver. Moreover, it has also been shown to have an impact on metabolic processes in the central nervous system. Astrocytes comprise the most abundant cell type in the central nervous system and actively participate in metabolic processes between blood vessels and neurons. However, the ability of adiponectin to control nutrient metabolism in astrocytes has not yet been fully elucidated. In this study, we investigated the effects of adiponectin on multiple metabolic processes in hypothalamic astrocytes. Adiponectin enhanced glucose uptake, glycolytic processes and fatty acid oxidation in cultured primary hypothalamic astrocytes. In line with these findings, we also found that adiponectin treatment effectively enhanced synthesis and release of monocarboxylates. Overall, these data suggested that adiponectin triggers catabolic processes in astrocytes, thereby enhancing nutrient availability in the hypothalamus.  相似文献   
215.
Food Science and Biotechnology - This study compared the antioxidant activity of extracts from Dendropanax morbifera (D. morbifera) Levillis leaves. The concentrations of flavonoids and polyphenols...  相似文献   
216.
Telecommunication Systems - One of the main requirements for next generation mobile or wireless communication systems is to effectively support a large number of machine type communication (MTC)...  相似文献   
217.
In this article, we study the time dependent Boussinesq (buoyancy) model with nonlinear viscosity depending on the temperature. We propose and analyze first and second order numerical schemes based on finite element methods. An optimal a priori error estimate is then derived for each numerical scheme. Numerical experiments are presented that confirm the theoretical accuracy of the discretization.  相似文献   
218.
Ventilation effectiveness is an indicator of the quality of supply air distribution in ventilated rooms. It is a representation of how well a considered space is ventilated compared to a perfect air mixing condition. Depending on pollutant properties and source position relative to the airflow, ventilation effectiveness can more or less successfully be used as an indicator of air quality and human exposure. This paper presents an experimentally and numerically based study that examines the relationship between ventilation effectiveness and particle concentration in typical indoor environments. The results show that the relationship varies predominantly with airflow pattern and particle properties. Fine particles (1 μm) follow the airflow pattern more strictly than coarse particles (7 μm), and the high ventilation effectiveness indicates better removal of fine particles than coarse particles. When a ventilation system provides high mixing in the space and ventilation effectiveness is close to one, particle sizes and source location have a relatively small effect on particle concentration in the breathing zone. However, when the supply air is short circuited and large stagnation zones exist within the space, the particle concentration in the breathing zone varies with particle size, source location, and airflow pattern. Generally, the results show that for fine particles (1 μm), increase of ventilation effectiveness reduces occupant exposure; while for coarser particles (7 μm), source location and airflow around the pollutant source are the major variables that affect human exposure.  相似文献   
219.
The effect of oligomer (M n =400–500 g/mol) on dye-sensitized solar cells (DSSC) employing polymer electrolytes consisting of poly(epichlorohydrin-co-ethylene oxide) (Epichlomer), LiI, 1-methyl-3-propylimidazolium iodide (MPII) and I2 is investigated. Five kinds of oligomer, poly(ethylene glycol) (PEG, M n =400 and 1,000 g/mol), poly(ethylene glycol) dimethyl ether (PEGDME), poly(propylene glycol) (PPG) and poly(ethylene glycol) diglycidyl ether (PEGDGE), were introduced to elucidate the role of terminal groups and chain length. The coordinative interactions and structures of polymer electrolytes were characterized by FT-IR spectroscopy and X-ray diffraction (XRD). The improved interfacial contact between the electrolytes and the electrodes by the oligomer addition was confirmed using a field-emission scanning electron microscope (FE-SEM). The electrolytes exhibited ionic conductivities on the order of 10?4 S/cm, but PEGDGE electrolyte showed much lower value (~10?8 S/cm). As a result, the energy conversion efficiency of DSSC was significantly affected by the oligomer. For example, the DSSC employing PEGDME with methyl terminal groups exhibited 3.95% at 100 mW/cm2, which is 200-fold higher than that employing PEGDGE.  相似文献   
220.
Glaucoma is an optic neuropathy in which the degeneration of retinal ganglion cells (RGCs) results in irreversible vison loss. Therefore, neuroprotection of RGCs from glaucomatous afflictions is crucial for glaucoma treatment. In this study, we aimed to investigate the beneficial effects of statins in the protection of RGCs using a rat model. Glaucomatous injury was induced in rats by chronic ocular hypertension (OHT) achieved after performing a circumlimbal suture. The rats were given either statins such as simvastatin and atorvastatin or a solvent weekly for 6 weeks. Retina sections underwent hematoxylin and eosin, Brn3a, or cleaved casepase-3 staining to evaluate RGC survival. In addition, modulation of glial activation was assessed. While the retinas without statin treatment exhibited increased RGC death due to chronic OHT, statins promoted the survival of RGCs and reduced apoptosis. Statins also suppressed chronic OHT-mediated glial activation in the retina. Our results demonstrate that statins exert neuroprotective effects in rat retinas exposed to chronic OHT, which may support the prospect of statins being a glaucoma treatment.  相似文献   
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