Publications by authors named "Kai Chi"

This study aimed to assess the characteristics of particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) from various stationary and mobile emission sources in Taiwan, with a focus on source apportionment and associated health risks. The northern power plant, equipped with bag filters operating at 150 °C, had significantly lower FPM and CPM levels (0.44 and 0.

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The aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism commonly exists in the East Asian populations and is associated with high risks of cardiovascular disease (CVD). However, the cellular and molecular mechanisms that underlie the ALDH2 rs671 mutant-linked high CVD remain elusive. Here, we show that macrophages derived from human ALDH2 rs671 carriers and ALDH2 knockout mice exhibited an enhanced pro-inflammatory macrophage phenotype and an impaired anti-inflammatory macrophage phenotype.

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The construction of crystalline metal-organic frameworks with regular architectures supportive of enhanced mass transport and bubble diffusion is imperative for electrocatalytic applications; however, this poses a formidable challenge. Here, a method is presented that confines the growth of nano-architectures to the liquid-liquid interface. Using this method, vertically oriented single crystalline nanowire arrays of an Ag-benzenehexathiol (BHT) conductive metal-organic framework (MOF) are fabricated via an "in-plane self-limiting and out-of-plane epitaxial growth" mechanism.

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In this Letter, we demonstrate a micro-displacement sensor based on a balloon-shaped fiber surface nanoscale axial photonic (SNAP) microresonator. The SNAP microresonator is fabricated by fiber bending to introduce nanoscale effective radius variations (ERVs) on the fiber surface. Displacement measurement based on the balloon-shaped SNAP microresonator is realized based on the ERV modulation resulting from the change in the bending radius of the balloon-shaped structure.

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COVID-19 has been a significant global concern due to its contagious nature. In May 2021, Taiwan experienced a severe outbreak, leading the government to enforce strict Pandemic Alert Level 3 restrictions in order to curtail its spread. Although previous studies in Taiwan have examined the effects of these measures on air quality, further research is required to compare different time periods and assess the health implications of reducing particulate matter during the Level 3 lockdown.

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Difluoromethylation reactions are increasingly important for the creation of fluorine-containing heterocycles, which are core groups in a diverse range of biologically and pharmacologically active ingredients. Ideally, this typically challenging reaction could be performed photocatalytically under mild conditions. To achieve this separation of redox processes would be required for the efficient generation of difluoromethyl radicals and the reduction of oxygen.

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The atomically dispersed Fe-N active site presents enormous potential for various renewable energy conversions. Despite its already remarkable catalytic performance, the local atomic microenvironment of each Fe atom can be regulated to further enhance its efficiency. Herein, a novel conceptual strategy that utilizes a simple salt-template polymerization method to simultaneously adjust the first coordination shell (Fe-NS) and second coordination shell (C-S-C, a structure similar to thiophene) of Fe-N isolated atoms is proposed.

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Article Synopsis
  • * The study examines PCDD/Fs, Polychlorinated biphenyls (PCBs), and Polychlorinated naphthalene (PCNs) across Northern and Central Taiwan, with sampling near waste incinerators, traffic, and industrial sites.
  • * Findings reveal that traffic sites have the highest particulate matter concentrations, with PCDD/Fs and PCBs peaking in winter and spring, while sintering plants are major PCDD/Fs sources, and woodchip boilers are leading contributors to
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In recent decades, heavy metals (HMs) have emerged as a global health concern. Unfortunately, in Pakistan, there is a general lack of awareness regarding the potential health risks associated with HMs pollution among automobile workers. Herein, we investigated the concentration of heavy metals such as lead (Pb), cadmium (Cd), and chromium (Cr) among automobile workers who were occupationally exposed in Mingora City, Khyber Pakhtunkhwa, Pakistan.

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Despite the development of advanced technologies for interventional coronary reperfusion after myocardial infarction, a substantial number of patients experience high mortality due to myocardial ischemia-reperfusion (MI/R) injury. An in-depth understanding of the mechanisms underlying MI/R injury can provide crucial strategies for mitigating myocardial damage and improving patient survival. Here, it is discovered that the 4-hydroxy-2-nonenal (4-HNE) accumulates during MI/R, accompanied by high rates of myocardial ferroptosis.

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Background: Uncontrolled hemorrhage is the leading cause of preventable death in combat and civilian trauma. Efficacious hemostatic agents in junctional hemorrhage can quell blood loss and improve survival. We hypothesized that a novel hemostatic foam of starch and chitosan would improve hemostasis, and thereby increase survival in a swine femoral artery hemorrhage model when compared with CombatGauze (CG).

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A family of novel highly π-extended tetracyano-substituted acene diimides, named as tetracyanodiacenaphthoanthracene diimides (TCDADIs), have been synthesized using a facile four-fold Knoevenagel condensation strategy. Unlike conventional cyano substitution reactions, our approach enables access to a large π-conjugated backbone with the in-situ formation of four cyano substitutents at room temperature while avoiding extra cyano-functionalization reactions. TCDADIs decorated with different N-alkyl substituents present good solubility, near-coplanar backbones, good crystallinity, and low-lying lowest unoccupied molecular orbital energies of -4.

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The precise synthesis of cycloarenes remains a challenging topic in both organic chemistry and materials science due to their unique fully fused macrocyclic π-conjugated structure. Herein, a series of alkoxyl- and aryl-cosubstituted cycloarenes (kekulene and edge-extended kekulene derivatives, K1-K3) were conveniently synthesized and an unexpected transformation of the anthryl-containing cycloarene K3 into a carbonylated cycloarene derivative K3-R was disclosed by controlling the temperature and gas atmosphere of the Bi(OTf)-catalyzed cyclization reaction. All their molecular structures were confirmed by single-crystal X-ray analysis.

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Developing efficient and stable electrocatalysts for hydrogen evolution reaction (HER) over a wide pH range and industrial large-scale hydrogen production is critical and challenging. Here, a tailoring strategy is developed to fabricate an outstanding HER catalyst in both acidic and alkaline electrolytes containing high-density atomically dispersed Ru sites anchored in the CoP nanoparticles supported on carbon spheres (NC@Ru -CoP). The obtained NC@Ru -CoP catalyst exhibits excellent HER performance with overpotentials of only 15 and 13 mV at 10 mA cm in 1 m KOH and 0.

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The Coronavirus Disease 2019 (COVID-19) pandemic provided an unprecedented natural experiment, that allowed us to investigate the impacts of different restrictive measures on personal exposure to specific volatile organic compounds (VOCs) and aldehydes and resulting health risks in the city. Ambient concentrations of the criteria air pollutants were also evaluated. Passive sampling for VOCs and aldehydes was conducted for graduate students and ambient air in Taipei, Taiwan, during the Level 3 warning (strict control measures) and Level 2 alert (loosened control measures) of the COVID-19 pandemic in 2021-2022.

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Driven by the ever-growing awareness of sustainability and circular economy, renewable, biodegradable, and recyclable fiber-based packaging materials are emerging as alternatives to fossil-derived, nonbiodegradable single-use plastics for the packaging industry. However, without functional barrier coatings, the water/moisture vulnerability and high permeability of fiber-based packaging significantly restrain its broader application as primary packaging for food, beverages, and drugs. Herein, we develop waterborne complex dispersion barrier coatings consisting of natural, biodegradable polysaccharides (i.

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Ultrafiltration (UF) is a common technique used in wastewater treatments. However, the issue of membrane fouling in UF can greatly hinder the effectiveness of the treatments. This study demonstrated a low-fouling composite cellulose membrane system based on microfibrillated cellulose (MFC) and silica nanoparticle additives.

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Designing (hetero)cycloarenes through the modifications of the π-topology and molecular packing of organic semiconductors has recently garnered considerable attention. However, their applications as an organic active layer in field-effect transistors are very limited, and the obtained hole carrier mobilities are less than 1 cm V s . In this work, a novel alkyl-substituted coplanar N-heterocycloarene (FM-C4) containing four carbazole units is successfully synthesized in crystalline form.

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Selectively generating active free radical (AFR) in tumor microenvironment (TME) can promote irreversible oxidation of biomolecules and damage tumor cells, resulting in effective tumor inhibition. However, therapeutic efficacy of AFR-based tumor suppression approaches is often limited by insufficient amount of HO or O within TME. To overcome this obstacle, we design a pH/photothermal dual responsive nanosystem (PFeSA@AS) for combined photothermal and nanocatalytic therapy in the near-infrared biowindow.

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The influence of long-range transport (LRT) of air pollutants on neighboring regions and countries has been documented. The magnitude of LRT aerosols and related constituents can misdirect control strategies for local air quality management. In this study, we aimed to quantify PM (diameter less than 2.

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Cycloarenes and heterocycloarenes display unique physical structures and hold great potential as organic semiconductors. However, the synthesis of (hetero)cycloarenes remains a big challenge, and there are limited reports on their applications. Herein, a series of nitrogen- and sulfur-codoped cycloarenes ( = 2, 3, 4) with branched alkyl substituents containing linear spacer groups from C to C have been conveniently synthesized.

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Adjusting the local coordination environment of single-atom electrocatalysts is a viable way to improve catalytic performance. The diversity of coordination geometric structures is limited to the traditional in-plane configuration, with only a little consideration paid to out-of-plane configurations due to the lack of suitable carriers and fabrication methods. This study reports out-of-plane coordination of Co-based single-atom catalysts mediated by the conjugated bipyridine-rich covalent organic framework (COF).

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To distinguish the influences of fuel type and truck speed on chemical composition and sub-toxic effects of particulates (PM) from engine emissions, biomarkers-interleukin-6 (IL-6), cytochrome P450 (CYP) 1A1, heme oxygenase (HO)-1, and NADPH-quinone oxidoreductase (NQO)-1-were studied in A549 human lung cells. Fuel type and truck speed preferentially affected the quantity and ion/polycyclic aromatic hydrocarbon (PAH) composition of PM, respectively. Under idling operation, phenanthrene was the most abundant PAH.

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The extracellular matrix (ECM) influences cellular behavior, function, and fate. The ECM surrounding Langerhans islets has not been investigated in detail to explain its role in the development and maturation of pancreatic-cells. Herein, a complex combination of the simulated ECM (sECM) has been examined with a comprehensive analysis of cell response and a variety of controls.

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