Publications by authors named "C-H Liu"

Increasing evidence has highlighted the effects of biodegradable microplastics (MPs) on soil organic matter (SOM), but the role of soil type and incubation time remains unclear. This study investigated the effects of polylactic acid microplastics (PLA-MPs) on the amount and molecular composition of dissolved organic matter (DOM) across three paddy soil types (Ferralsol, Alfisol, and Mollisol) and incubation times, revealing soil-specific patterns in DOM transformation: PLA-MPs reduced DOM content in Ferralsol and Alfisol by 29.3-68.

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A comprehensive study of the angular distributions in the bottom-baryon decays Λ_{b}^{0}→Λ_{c}^{+}h^{-}(h=π,K), followed by Λ_{c}^{+}→Λh^{+} with Λ→pπ^{-} or Λ_{c}^{+}→pK_{S}^{0} decays, is performed using a data sample of proton-proton collisions corresponding to an integrated luminosity of 9  fb^{-1} collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. The decay parameters and the associated charge-parity (CP) asymmetries are measured, with no significant CP violation observed. For the first time, the Λ_{b}^{0}→Λ_{c}^{+}h^{-} decay parameters are measured.

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A palladium-catalyzed Catellani-type [2+2+2] annulation reaction of aryl iodides, bromothiophenes, and norbornadiene, which proceeds via a tandem Heck coupling/double C-H bond activation and retro-Diels-Alder pathway to access thiophene-fused polyaromatics, is reported. The key feature of this protocol represents a NBD/NBE retaining annulation.

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The nitrogen-rich metal-organic framework (MOF) , featuring a melamine (MA) functional group, enables efficient one-step CH purification and methanol-to-olefins (MTO) product separation. At 298 K, its adsorption capacity follows the order CH > CH > CH > CH. Breakthrough experiments showed that produced pure CH from C mixtures with a productivity of 22.

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Background: Guidelines emphasize quiet settings for blood pressure (BP) measurement.

Objective: To determine the effect of noise and public environment on BP readings.

Design: Randomized crossover trial of adults in Baltimore, Maryland.

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Isoindigo (IID)-based non-fullerene acceptors, known for their broad absorption spectra and high charge carrier mobilities, play a crucial role in organic photovoltaics. In this study, two A-DA'D-A type unfused ring acceptors (URAs), IDC8CP-IC and IDC6CP-IC, were designed and synthesized using cyclopentadithiophene (CPDT) and IID core units, each functionalized with different alkyl chains (2-hexyldecyl and 2-octyldodecyl), through an atom- and step-efficient direct C-H arylation (DACH) method. Both URAs, despite the absence of non-covalent conformation locking between CPDT and IID, demonstrated favorable molecular planarity, broad absorption ranges, low band gaps, and high molar absorption coefficients.

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This review highlights significant advances in iron-catalyzed cross-dehydrogenative coupling (CDC), a method pivotal for forming carbon-carbon (C-C) bonds directly from C-H bonds. This technique uses iron-a naturally abundant, inexpensive, and environmentally benign transition metal-as a catalyst to facilitate the coupling of two unfunctionalized C-H bonds. This method stands out for avoiding pre-functionalized substrates, reducing both waste and cost in organic synthesis.

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Achieving the adsorptive separation and chromatographic separation of industrially the important chemicals toluene and methylcyclohexane using the same material is a highly desirable goal. We have successfully accomplished this using a fluorinated macrocycle tetrafluoroterphen[3]arene (4FTP3), which was synthesized and used for gas chromatographic separation in our previous work. The macrocycle 4FTP3 permitted the adsorptive separation of toluene from a toluene/methylcyclohexane mixture (1:1, v/v) with a purity of 99.

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Background: The decrease in S-nitrosoglutathione reductase (GSNOR) leads to an elevation of S-nitrosylation, thereby exacerbating the progression of cardiomyopathy in response to hemodynamic stress. However, the mechanisms under GSNOR decrease remain unclear. Here, we identify NEDD4 (neuronal precursor cell expressed developmentally downregulated 4) as a novel molecule that plays a crucial role in the pathogenesis of pressure overload-induced cardiac hypertrophy, by modulating GSNOR levels, thereby demonstrating significant therapeutic potential.

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New efficient and sustainable methods for the removal of malachite green (MG) from environmental media are needed. In this study, corn straw was co-pyrolyzed with montmorillonite under a variety of conditions (400, 500, 600, and 700 °C and 10-40 wt% montmorillonite), without any use of toxic chemicals, to produce a series of biochar-clay composites. Characteristics of the composites that make them promising contaminant sorbents include a uniform lamellar-particle micromorphology, enhanced mesoporous structure and surface area (53.

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Background: Spread through air spaces (STAS) in lung adenocarcinoma (LUAD) is a distinct pattern of intrapulmonary metastasis where tumor cells disseminate within the pulmonary parenchyma beyond the primary tumor margins. This phenomenon was officially included in the World Health Organization (WHO)'s classification of lung tumors in 2015. STAS is characterized by the spread of tumor cells in three forms: single cells, micropapillary clusters, and solid nests.

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Reported herein is the first example of a ruthenium-catalyzed C-H activation/annulation of phenothiazine-3-carbaldehydes to construct structurally diverse pyrido[3,4-]phenothiazin-3-iums with dual-emission characteristics. Novel organic single-molecule white-light materials based on pyrido[3,4-]phenothiazin-3-iums with dual-emission and thermally activated delayed fluorescence (TADF) characteristics have been developed for the first time herein. Furthermore, the dual-emission molecule could be fabricated as water-dispersed NPs, which could be applied in two-channel emission intensity ratio imaging to observe the intercellular structure and can specifically target the cell membrane.

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The group 1 alumanyls, [{SiN}AlM] (M = K, Rb, Cs; SiN = {CHSiMeNDipp}), display a variable kinetic facility (K < Rb < Cs) toward oxidative addition of the acidic C-H bond of terminal alkynes to provide the corresponding alkali metal hydrido(alkynyl)aluminate derivatives. Theoretical analysis of the formation of these compounds through density functional theory (DFT) calculations implies that the experimentally observed changes in reaction rate are a consequence of the variable stability of the [{SiN}AlM] dimers, the integrity of which reflects the ability of M to maintain the polyhapto group 1-arene interactions necessary for dimer propagation. These observations highlight that such "on-dimer" reactivity takes place sequentially and also that the ability of each constituent Al(I) center to effect the activation of the organic substrate is kinetically differentiated.

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The synthesis of polymers with well-defined composition, architecture, and functionality has long been a focal area of research in the field of polymer chemistry. The advancement of controlled radical polymerization (CRP) has facilitated the synthesis of precise polymers, which are endowed with new properties and functionalities, thereby exhibiting a wide range of applications. However, radical polymerization faces several challenges, such as oxygen intolerance, and common thermal initiation methods may lead to side reactions and depolymerization.

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As an efficient, sustainable, and environmentally friendly semiconductor material, covalent organic frameworks (COFs) can generate hydrogen peroxide (HO) by photocatalysis, attracting wide attention in recent years. Herein, the effects of hydroxyl, methoxyl, and vinyl groups of imide-linked two-dimensional (2D) COFs on the photocatalytic production of HO were studied theoretically and experimentally. The introduction of vinyl groups greatly promotes the photogenerated charge separation and migration of COFs, providing more oxygen adsorption sites, stronger proton affinity, and lower intermediate binding energy, which effectively facilitates the rapid conversion of oxygen to HO.

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A novel palladium-catalyzed allylic C-H alkylation of terminal olefins with 3-carboxamide oxindoles is described. A variety of new 3-carboxamide-3-allylation oxindoles with an all-carbon quaternary center were obtained in moderate to good yields (up to 99%). In addition, the asymmetric version of this reaction was also explored, providing moderate enantioselectivity.

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A TEMPO-mediated β-ketoalkylation of enaminoesters with cyclopropanols under metal-free conditions is herein described. This reaction provides a straightforward and highly efficient route to β-keto alkyl substituted enaminoesters for the first time, which could be rapidly and efficiently converted into synthetically useful 2-alkoxycarbonyl functionalized 1,5-diketones. Moreover, the practicability of this protocol is successfully demonstrated by scale-up experiments and the late-stage functionalization of natural products and pharmaceutically relevant molecules.

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Background: Chronic rhinosinusitis (CRS) and olfactory dysfunction (OD) are prevalent disease complications in people with cystic fibrosis. These understudied comorbidities significantly impact quality of life. The impact of highly effective modulator therapy (HEMT) in young children with cystic fibrosis (YCwCF) on these disease complications is unknown.

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Optically pure monosubstituted [n]paracyclophanes are promising candidates for material synthesis, asymmetric catalysis, and drug discovery. Thus far, only a few catalytic asymmetric synthesis processes have been reported for assessing these strained atropisomers. In this study, we describe a highly enantioselective synthesis of monosubstituted [n]paracyclophanes by combining desymmetrization and kinetic resolution.

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Here we present a regio- and stereoselective alkylation approach for unprotected saccharides using synergistic boronic acid and photoredox catalysis. Targeting the equatorial C-H bond of the -1,2-diol motif, this method employs MeB(OH) as a catalyst. Mechanistic investigations indicate that the formation of a tetracoordinate boron species, resulting from the interaction between the cyclic boronic diol ester and a free hydroxyl group in the saccharide, is critical to this transformation.

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This paper investigates the use of the BOTDA (Brillouin Optical Time-Domain Analysis) technology to monitor a large-scale bored pile wall in the field. Distributed fiber optic sensors (DFOSs) were deployed to measure internal temperature and strain changes during cement grouting, hardening, and excavation-induced deformation of a secant pile wall. The study details the geological conditions and DFOS installation process.

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Hydraulic structures are frequently subjected to soft-water or acidic environments, necessitating serious consideration of the long-term effects of calcium leaching on the durability of concrete structures. Three types of common Portland cement (ordinary Portland cement, moderate-heat cement, and low-heat cement) paste samples widely applied to hydraulic concrete were immersed in a 6 mol/L NHCl solution to simulate accelerated calcium leaching behavior. The mass loss, porosity, leaching depth, compressive strength, and Ca/Si ratio of the three types of pastes were measured at different immersion stages (0, 14, 28, 56, 91, 140, and 180 days).

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Pseudouridine (Ψ) is the most abundant RNA modification, yet studies of Ψ have been hindered by a lack of robust methods to profile comprehensive Ψ maps. Here we utilize bisulfite-induced deletion sequencing to generate transcriptome-wide Ψ maps at single-base resolution across various plant species. Integrating ribosomal RNA, transfer RNA and messenger RNA Ψ stoichiometry with mRNA abundance and polysome profiling data, we uncover a multilayered regulation of translation efficiency through Ψ modifications.

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Mimicking the superstructures and properties of spherical biological encapsulants such as viral capsids and ferritin offers viable pathways to understand their chiral assemblies and functional roles in living systems. However, stereospecific assembly of artificial polyhedra with mechanical properties and guest-binding attributes akin to biological encapsulants remains a formidable challenge. Here we report the stereospecific assembly of dynamic supramolecular snub cubes from 12 helical macrocycles, which are held together by 144 weak C-H hydrogen bonds.

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Direct functionalization of native (N-H) indoles via C-H activation remains a challenge. Herein, we report a salicylaldehyde-promoted cobalt-catalyzed selective C2-H Heck reaction of native (N-H) indoles with both active and unactivated olefins in the presence of free N-H bonds. A series of structurally diverse C2-alkenylated native (N-H) indoles including natural product and drug derivatives were prepared directly and effectively without additional preprotection and deprotection procedures.

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