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1.
Mar Drugs ; 21(12)2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-38132924

RESUMEN

Seaweed extracts and their specific polysaccharides are widely known for their ability to act as reducing and capping agents during nanoparticle synthesis. Their application is highly favored in green synthesis methods, owing to their eco-friendliness, cost-effectiveness, and remarkable time and energy efficiency. In this study, fucoidan extracted from Undaria pinnatifida sporophyll (UPS) is introduced as a polysaccharide that effectively serves as a dual-function reducing and capping agent for the synthesis of gold nanoparticles (AuNPs). Results from various analyses indicate that AuNPs derived from UPS extract display a uniform spherical shape with an average size of 28.34 ± 1.15 nm and a zeta potential of -37.49 ± 2.13 mV, conclusively confirming the presence of Au. The FT-IR spectra distinctly revealed the characteristic fucoidan bands on the stabilized UPS-AuNPs surface. A 1H-NMR analysis provided additional confirmation by revealing the presence of specific fucoidan protons on the UPS-AuNPs surface. To comprehensively evaluate the impact of UPS extract, UPS-AuNPs, and fucoidan on the biological properties of adipocytes, a rigorous comparative analysis of lipid droplet formation and morphology was conducted. Our findings revealed that adipocytes treated with UPS extract, fucoidan, and UPS-AuNPs, in that order, exhibited a reduction in the total lipid droplet surface area, maximum Ferret diameter, and overall Nile red staining intensity when compared to mature white adipocytes. Furthermore, our analysis of the effects of UPS extracts, UPS-AuNPs, and fucoidan on the expression of key markers associated with white adipose tissue browning, such as UCP1, PGC1a, and PRDM16, demonstrated increased mRNA and protein expression levels in the following order: UPS-AuNPs > fucoidan > UPS extracts. Notably, the production of active mitochondria, which play a crucial role in enhancing energy expenditure in beige adipocytes, also increased in the following order: UPS-AuNPs > fucoidan > UPS extract. These findings underscore the pivotal role of UPS extract, fucoidan, and UPS-AuNPs in promoting adipocyte browning and subsequently enhancing energy expenditure.


Asunto(s)
Nanopartículas del Metal , Undaria , Animales , Oro , Adipocitos Blancos , Espectroscopía Infrarroja por Transformada de Fourier , Hurones , Polisacáridos/farmacología , Polisacáridos/química , Undaria/química
2.
PLoS One ; 18(11): e0294576, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38011085

RESUMEN

We investigated the attributes and attribute levels that affect researcher preferences for chemical compounds. We conducted a conjoint analysis on survey data of Korean researchers using chemical compounds from the Korean Chemical Bank (KCB). The analysis estimated the part-worth utility for each attribute's level, calculated relative importance of attributes, and classified user segmentation with different patterns. The results show that the structure database offers the highest part-worth utility to researchers, followed by high new functionality, price, screening service, and drug action data provided only by the KCB. Notably, researchers view the offer of a structured database and high new functionality as more important than other attributes in decision-making about research and development of chemical compounds. Furthermore, the results of segmentation analysis demonstrated that researchers have distinct usage patterns of chemical compounds: researchers consider structure database and high new functionality in cluster 1; and high new functionality and price in cluster 2, to be the most appealing. We discussed some policy and strategic implications based on the findings of this study and proposed some limitations.


Asunto(s)
Manejo de Datos , Prioridad del Paciente , Humanos , Encuestas y Cuestionarios , Investigadores
3.
Sensors (Basel) ; 11(1): 852-63, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22346606

RESUMEN

Wireless Sensor Networks (WSNs) can be implemented as one of sensor systems in Network Centric Warfare (NCW). Mobility support and energy efficiency are key concerns for this application, due to multiple mobile users and stimuli in real combat field. However, mobility support approaches that can be adopted in this circumstance are rare. This paper proposes Multiple Mobility Support Approach (MMSA) based on Probing Environment and Adaptive Sleeping (PEAS) to support the simultaneous mobility of both multiple users and stimuli by sharing the information of stimuli in WSNs. Simulations using Qualnet are conducted, showing that MMSA can support multiple mobile users and stimuli with good energy efficiency. It is expected that the proposed MMSA can be applied to real combat field.

4.
Appl Opt ; 46(36): 8591-9, 2007 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-18091969

RESUMEN

A major problem of optical microscopes is their small depth-of-field (DOF), which hinders automation of micro object manipulation using visual feedback. Wavefront coding, a well-known method for extending DOF, is not suitable for direct application to micro object manipulation systems based on visual feedback owing to its expensive computational cost and due to a trade-off between the DOF and the image resolution properties. To solve such inherent problems, a flexible DOF imaging system using a spatial light modulator in the pupil plane is proposed. Especially, the trade-off relationship is quantitatively analyzed by experiments. Experimental results show that, for low criterion resolution, the DOF increases as the strength of the mask increases, while such a trend was not found for high criterion resolution. With high criterion resolution, the DOF decreases as the mask strength increases when high-resolution images are required. The results obtained can be used effectively to find the optimum mask strength given the desired image resolution.

5.
J Phys Chem B ; 110(35): 17309-14, 2006 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-16942064

RESUMEN

The electro-nanopatterning and mechanism of pattern formation in azobenzene-containing layer-by-layer (LbL) ultrathin films is described using surface probe microscopy techniques. First, arrays of nanodots were patterned on these films to investigate applied time at constant voltage bias dependence in electro-nanopatterning. The anisotropic mass transport and polar alignment of the azobenzene-containing films were observed after applying the electric field and heating the sample locally with the cantilever tip. On the basis of this novel phenomenon, small-sized surface relief gratings (SRG)s and their alignment were fabricated and observed by current-sensing atomic force microscopy. The rate of mass transport for the polymer is mainly controlled by the applied time at constant voltage bias between the cantilever and the electrode/substrate.

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