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1.
Nano Lett ; 24(33): 10055-10061, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39047260

RESUMEN

Nonlocal metasurfaces, exemplified by resonant waveguide gratings (RWGs), spatially and angularly configure optical wavefronts through narrow-band resonant modes, unlike the broad-band and broad-angle responses of local metasurfaces. However, forward design techniques for RWGs remain constrained at lower efficiency. Here, we present a topology-optimized metasurface resonant waveguide grating (MRWG) composed of titanium dioxide on a glass substrate capable of operating simultaneously at red, yellow, green, and blue wavelengths. Through adjoint-based topology optimization, while considering nonlocal effects, we significantly enhance its diffraction efficiency, achieving numerical efficiencies up to 78% and Q-factors as high as 1362. Experimentally, we demonstrated efficiencies of up to 59% with a Q-factor of 93. Additionally, we applied our topology-optimized metasurface to color selectivity, producing vivid colors at 4 narrow-band wavelengths. Our investigation represents a significant advancement in metasurface technology, with potential applications in see-through optical combiners and augmented reality platforms.

2.
J Transcult Nurs ; 29(4): 369-378, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29308707

RESUMEN

BACKGROUND: Studies have indicated that one of the key factors in relieving depression in older people is social network support, especially from the family. In Chinese society, the traditional value of filial piety strongly influences daily interactions and behavior. The purpose of this study was to examine older people's perceptions of filial piety and to explore the correlation between filial piety and depression in older people. METHOD: In this systematic literature review of seven databases (CEPS, Cochrane, PubMed/Medicine, OVID, CINAHL, ProQuest, and PsycINFO), eight studies on the correlation between filial piety and depression in older people were selected, six of which were included in the present meta-analysis. RESULTS: The studies included in this review lacked consistency regarding the screening and measurement instruments used. Two groups of meta-analyses (four studies) illustrated that filial piety was negatively correlated with depression in older people ( r = -0.196, p < .001, 95% confidence interval [CI] [-0.283, -0.106] and r = -0.139, p = .006, 95% CI [-0.235, -0.041]), suggesting that an increase in older people's perception of their children's filial piety was correlated with a reduction in their depression. CONCLUSIONS: Filial piety was correlated with depression in older people. Future studies should focus on clarifying the concept of filial piety to aid in the application of appropriate measurement tools and the development of intervention measures that could enhance the care provided for depression in older people.


Asunto(s)
Depresión/etiología , Relaciones Familiares/psicología , Anciano , Anciano de 80 o más Años , Depresión/psicología , Humanos , Relaciones Intergeneracionales , Apoyo Social
3.
Chirality ; 28(1): 65-71, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26487505

RESUMEN

Chiral O,N,O-tridentate phenol ligands bearing a camphor backbone were found to be effective chiral catalysts for the enantioselective addition of diethylzinc to aromatic aldehydes, resulting in high enantioselectivities (80-95% ee) at room temperature.

4.
J Virol ; 88(16): 8883-99, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24872582

RESUMEN

UNLABELLED: Epstein-Barr virus (EBV) BKRF3 shares sequence homology with members of the uracil-N-glycosylase (UNG) protein family and has DNA glycosylase activity. Here, we explored how BKRF3 participates in the DNA replication complex and contributes to viral DNA replication. Exogenously expressed Flag-BKRF3 was distributed mostly in the cytoplasm, whereas BKRF3 was translocated into the nucleus and colocalized with the EBV DNA polymerase BALF5 in the replication compartment during EBV lytic replication. The expression level of BKRF3 increased gradually during viral replication, coupled with a decrease of cellular UNG2, suggesting BKRF3 enzyme activity compensates for UNG2 and ensures the fidelity of viral DNA replication. In immunoprecipitation-Western blotting, BKRF3 was coimmuno-precipitated with BALF5, the polymerase processivity factor BMRF1, and the immediate-early transactivator Rta. Coexpression of BMRF1 appeared to facilitate the nuclear targeting of BKRF3 in immunofluorescence staining. Residues 164 to 255 of BKRF3 were required for interaction with Rta and BALF5, whereas residues 81 to 166 of BKRF3 were critical for BMRF1 interaction in glutathione S-transferase (GST) pulldown experiments. Viral DNA replication was defective in cells harboring BKRF3 knockout EBV bacmids. In complementation assays, the catalytic mutant BKRF3(Q90L,D91N) restored viral DNA replication, whereas the leucine loop mutant BKRF3(H213L) only partially rescued viral DNA replication, coupled with a reduced ability to interact with the viral DNA polymerase and Rta. Our data suggest that BKRF3 plays a critical role in viral DNA synthesis predominantly through its interactions with viral proteins in the DNA replication compartment, while its enzymatic activity may be supplementary for uracil DNA glycosylase (UDG) function during virus replication. IMPORTANCE: Catalytic activities of both cellular UDG UNG2 and viral UDGs contribute to herpesviral DNA replication. To ensure that the enzyme activity executes at the right time and the right place in DNA replication forks, complex formation with other components in the DNA replication machinery provides an important regulation for UDG function. In this study, we provide the mechanism for EBV UDG BKRF3 nuclear targeting and the interacting domains of BKRF3 with viral DNA replication proteins. Through knockout and complementation approaches, we further demonstrate that in addition to UDG activity, the interaction of BKRF3 with viral proteins in the replication compartment is crucial for efficient viral DNA replication.


Asunto(s)
Replicación del ADN/genética , ADN Viral/genética , Herpesvirus Humano 4/genética , Uracil-ADN Glicosidasa/genética , Uracil-ADN Glicosidasa/metabolismo , Proteínas Virales/genética , Proteínas Virales/metabolismo , Línea Celular , Línea Celular Tumoral , Núcleo Celular/genética , Núcleo Celular/metabolismo , Citoplasma/genética , Citoplasma/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , ADN Polimerasa Dirigida por ADN/genética , ADN Polimerasa Dirigida por ADN/metabolismo , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/metabolismo , Infecciones por Virus de Epstein-Barr/virología , Genoma Viral/genética , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Células HEK293 , Células HeLa , Herpesvirus Humano 4/metabolismo , Humanos , Replicación Viral/genética
5.
Int J Med Mushrooms ; 15(4): 393-405, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23796221

RESUMEN

A process of tandem cultivation for the production of green and invaluable bioproducts (levan and Cordycepes militaris) useful for medical applications has been successfully developed. The process involves first cultivating Bacillus subtilis strain natto in sucrose medium to produce levan, followed by the subsequent cultivation of C. militaris in liquid- and solid-state cultures using the spent medium from levan fermentation as substrates. The factors affecting the cell growth and production of metabolites of C. militaris were investigated, and the various metabolites produced in the culture filtrate, mycelia, and fruiting body were analyzed. In addition, cordycepin was prepared from the solid waste medium of C. militaris. This is an excellent example in the development of cost effective biorefineries that maximize useful product formation from the available biomass. The preparation of cordycepin from solid waste medium of C. militaris using a method with high extraction efficiency and minimum solvent usage is also environmentally friendly.


Asunto(s)
Ascomicetos/fisiología , Desoxiadenosinas/metabolismo , Animales , Medios de Cultivo , Fermentación , Concentración de Iones de Hidrógeno
6.
Org Biomol Chem ; 9(9): 3272-8, 2011 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-21431234

RESUMEN

Seven new polyoxygenated steroids, hirsutosterols A-G (1-7), were isolated from the Formosan soft coral Cladiella hirsuta. Their structures were elucidated by spectroscopic methods, particularly in 1D and 2D NMR experiments. The absolute configurations of 1 and 5 were determined by Mosher's method. Sterols 4-6 possess hydroxy groups at C-9 and C-11 and might be oxidatively cleaved to the corresponding 9,11-secosterols. Hirsutosterol A (1) was found to exhibit a stronger cytotoxicity against a limited panel of cancer cell lines.


Asunto(s)
Antozoos/química , Oxígeno/química , Esteroides/química , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Hidroxilación , Isomerismo , Ratones , Modelos Moleculares , Estructura Molecular , Esteroides/aislamiento & purificación , Esteroides/farmacología , Relación Estructura-Actividad
7.
Chaos ; 21(4): 043126, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22225363

RESUMEN

In Satake's generalized resource budget model of ecology, which was modified from Isagi's resource budget model, Satake and Iwasa illustrated, by computing the positive Lyapunov exponent, that if the depletion coefficient is greater than one, then the system is chaotic. However, a positive Lyapunov exponent implies only sensitivity in Devaney's chaos. Therefore, this work presents mathematical viewpoints and numerical analysis on Satake's generalized resource budget model to rigorously prove that the generalized resource budget model is chaotic in Devaney's sense by using the snapback repeller theory and the topological entropy theory. Moreover, this work also investigates that there is a significant difference between the behaviors of positive odd depletion coefficients and positive even depletion coefficients under numerical computations.


Asunto(s)
Algoritmos , Modelos Biológicos , Dinámicas no Lineales , Desarrollo de la Planta , Reproducción/fisiología , Simulación por Computador
8.
J Nat Prod ; 73(11): 1785-91, 2010 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-20979397

RESUMEN

Eight new eunicellin-base diterpenoids, hirsutalins A-H (1-8), were isolated from the soft coral Cladiella hirsuta. Their structures were elucidated by spectroscopic methods, particularly in 1D and 2D NMR experiments. The absolute configuration of 1 was determined by Mosher's method. Compounds 1, 5, and 6 have been shown to exhibit cytotoxicity toward several cancer cell lines. Compounds 2-4 and 8 were found to display significant in vitro anti-inflammatory activity in LPS-stimulated RAW264.7 macrophage cells by inhibiting the expression of the iNOS protein, with compound 2 also effectively reducing the level of COX-2 protein.


Asunto(s)
Antozoos/química , Antiinflamatorios no Esteroideos/aislamiento & purificación , Antineoplásicos/aislamiento & purificación , Inhibidores de la Ciclooxigenasa 2/aislamiento & purificación , Diterpenos/aislamiento & purificación , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Animales , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Inhibidores de la Ciclooxigenasa 2/química , Inhibidores de la Ciclooxigenasa 2/farmacología , Diterpenos/química , Diterpenos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ratones , Estructura Molecular , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Resonancia Magnética Nuclear Biomolecular
9.
Comput Methods Programs Biomed ; 92(3): 289-93, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18508153

RESUMEN

A beam-hardening effect is a common problem affecting the quantitative aspects of X-ray computed tomography (CT). We have developed two statistical reconstruction algorithms for poly-energetic X-ray CT that can effectively reduce the beam-hardening effect. Phantom tests were used to evaluate our approach in comparison with traditional correction methods. Unlike previous methods, our algorithm utilizes multiple energy-corresponding blank scans to estimate the attenuation map for a particular energy spectrum. Therefore, our algorithm is an energy-selective reconstruction. In addition to benefits over other statistical algorithms for poly-energetic reconstruction, our algorithm has the advantage of not requiring prior knowledge of the object material, the energy spectrum of the source and the energy sensitivity of the detector. The results showed an improvement in coefficient of variation, uniformity and signal-to-noise ratio; overall, this novel approach produces a better beam-hardening correction.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Tomografía Computarizada por Rayos X/métodos , Humanos
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