Publications by authors named "Chi-Fan Chen"

Telomere shortening is a hallmark of aging and eventually constrains the proliferative capacity of cells. The protocols discussed here are used for monitoring telomeres comprehensively in Aeolosoma viride, a model system for regeneration studies. We present methods for analyzing the activity of telomerase enzyme in regenerating tissue by telomeric repeat amplification protocol (TRAP) assay, for comparing telomere length between existing tissue and newly regenerated tissue by telomere restriction fragment (TRF) assay, as well as for visualizing telomeres by fluorescence in situ hybridization (FISH).

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Aging is a complex process involving declines in various cellular and physical functionalities, including regenerative ability. Telomere maintenance is thought to be necessary for regeneration, and telomere attrition is one mechanism that contributes to aging. However, it is unclear if aging affects regeneration owing to deterioration of telomeric maintenance.

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This study integrated estimated oxidation ratio of sulfur (SOR) and oxidation ratio of nitrogen (NOR) with source-receptor modeling results to identify the effects of terrain and monsoons on ambient aerosols in an urban area (north basin) and a rural area (south basin) of the Taichung Basin. The estimated results indicate that the conversion of sulfur mainly occurs in fine particles (PM₂.₅), whereas the conversion of nitrogen occurs in approximately equal quantities of PM₂.

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The science parks have helped shape Taiwan as a high-tech island with a good reputation worldwide. But some complaints on air pollution from the science parks have recently risen. To better understand the environmental effects of volatile organic compounds (VOCs) emitted from various high-tech factories in a science park, this study uses a source-receptor approach to characterize the environmental effects of VOCs from control device exhaust in Taichung Science Park.

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The rice BGlu1 β-D-glucosidase nucleophile mutant E386G is a glycosynthase that catalyzes the synthesis of cellooligosaccharides from α-d-glucopyranosyl fluoride (GlcF) donor and p-nitrophenyl (pNP) cellobioside (Glc2-pNP) or cello-oligosaccharide acceptors. When activity with other donors and acceptors was tested, the initial enzyme preparation cleaved pNP-β-D-glucopyranoside (Glc-pNP) and pNP-β-D-fucopyranoside (Fuc-pNP) to pNP and glucose and fucose, suggesting contamination with wild type BGlu1 β-glucosidase. The products from reaction of GlcF and Fuc-pNP included Fuc-β-(1→3)-Fuc-pNP, Glc-β-(1→3)-Fuc-pNP, and Fuc-β-(1→4)-Glc-β-(1→3)-Fuc-pNP, suggesting the presence of both wild type BGlu1 and its glycosynthase.

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Inelastic light scattering spectroscopy has, since its first discovery, been an indispensable tool in physical science for probing elementary excitations, such as phonons, magnons and plasmons in both bulk and nanoscale materials. In the quantum mechanical picture of inelastic light scattering, incident photons first excite a set of intermediate electronic states, which then generate crystal elementary excitations and radiate energy-shifted photons. The intermediate electronic excitations therefore have a crucial role as quantum pathways in inelastic light scattering, and this is exemplified by resonant Raman scattering and Raman interference.

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We present a generic and efficient chemical patterning method based on local plasma-induced conversion of surface functional groups on self-assembled monolayers (SAMs). Here, spatially controlled plasma exposure is realized by elastomeric poly(dimethylsiloxane) (PDMS) contact masks or channel stamps with feature sizes ranging from nanometer, micrometer, to centimeter. This chemical conversion method has been comprehensively characterized by a set of techniques, including contact angle measurements, X-ray photoelectron spectroscopy (XPS), scanning photoelectron microscopy (SPEM), scanning electron microscopy (SEM), and scanning Kelvin probe microscopy (SKPM).

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We report on the self-assembly of large-area, highly ordered 2D superlattices of alkanethiolate-stabilized gold nanoparticles ( approximately 10.5 nm in core diameter) onto quartz substrates with varying lattice constants, which can be controlled by the alkyl chain lengths, ranging from C12 (1-dodecanethiolate), C14 (1-tetradecanethiolate), C16 (1-hexadecanethiolate), to C18 (1-octadecanethiolate). These 2D nanoparticle superlattices exhibit strong collective surface plasmon resonance that is tunable via the near-field coupling of adjacent nanoparticles.

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A new approach is introduced for electrostatically guided adsorption of colloidal nanoparticles onto a patterned self-assembled monolayer (SAM) with feature sizes ranging from nm to mm. Patterning of the adsorption templates is realized by electric-field-induced anodic oxidation of aminosilane SAM using an ink-free method. In this versatile method, both "positive" and "negative" type pattern transfers are possible.

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