Publications by authors named "Jian-rong Gao"

As a two-dimensional planar material with low depth profile, a metasurface can generate non-classical phase distributions for the transmitted and reflected electromagnetic waves at its interface. Thus, it offers more flexibility to control the wave front. A traditional metasurface design process mainly adopts the forward prediction algorithm, such as Finite Difference Time Domain, combined with manual parameter optimization.

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Article Synopsis
  • Gut bacteria convert tryptophan into metabolites like indole-3-acetic acid, which are often lower in patients with alcohol-related liver damage.
  • This study tested engineered bacteria (EcN-Ahr) in mice to see if they could produce these beneficial indoles and protect against ethanol-induced liver disease.
  • Results showed that EcN-Ahr helped improve liver health by activating immune responses, but this effect was lost in mice lacking specific immune receptors (Ahr) related to interleukin 22 production.
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Enteric hyperoxaluria (EH) is a metabolic disease caused by excessive absorption of dietary oxalate leading to the formation of chronic kidney stones and kidney failure. There are no approved pharmaceutical treatments for EH. SYNB8802 is an engineered bacterial therapeutic designed to consume oxalate in the gut and lower urinary oxalate as a potential treatment for EH.

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A full demonstration of the Fourier phase grating used as 4.7 THz local oscillator (LO) multiplexer for Galactic/Extragalactic ULDB Spectroscopic Terahertz Observatory (GUSTO) is presented in this paper, including its design, modeling, tolerance analysis, and experimental characterizations of the angular and intensity distributions among 2 × 4 output beams and the power efficiency. A quantum cascade laser (QCL) is used to generate the input beam for evaluation of the grating performance in its all relevant aspects with an accuracy level never reported before, where good agreements with modeling results are found.

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We present a terahertz spatial filter consisting of two back-to-back (B2B) mounted elliptical silicon lenses and an opening aperture defined on a thin gold layer between the lenses. The beam filtering efficiency of the B2B lens system is investigated by simulation and experiment. Using a unidirectional antenna coupled 3rd-order distributed feedback (DFB) quantum cascade laser (QCL) at 3.

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Synthetic biology is a powerful tool to create therapeutics which can be rationally designed to enable unique and combinatorial functionalities. Here we utilize non-pathogenic E coli Nissle as a versatile platform for the development of a living biotherapeutic for the treatment of cancer. The engineered bacterial strain, referred to as SYNB1891, targets STING-activation to phagocytic antigen-presenting cells (APCs) in the tumor and activates complementary innate immune pathways.

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Large heterodyne receiver arrays (~100 pixel) allow astronomical instrumentations to map more area within limited space mission lifetime. One challenge is to generate multiple local oscillator (LO) beams. Here, we succeeded in generating 81 beams at 3.

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A method for the allylic alkylation of aminophenol with alkynes was developed using a palladium-catalysed allylation reaction with 100% atom economy. A series of structurally diverse N-allylic substituted allylamines were synthesized in good yields with high chemo-, regio-, and stereoselectivities under mild conditions.

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A Ni(ClO)-catalyzed enantioselective [2 + 2] cycloaddition of -allenamides with cyclic -sulfonylketimines was developed, which regioselectively occurred at the proximal C[double bond, length as m-dash]C bonds of the -allenamides. Broad substrate scope of -allenamides and cyclic -sulfonylketimines was observed. A range of fused polysubstituted azetidines bearing quaternary stereocenters were afforded in good yields and with excellent enantioselectivities (up to 99%).

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Enantioselective alkynylation of cyclic N-sulfonyl α-ketiminoesters with terminal alkynes was developed by using an Ni(ClO)/(R)-DTBM-Segphos complex as a catalyst. A range of propargylic amides bearing quaternary stereocenters were afforded in excellent enantioselectivities (up to 97% ee). Theoretical studies revealed that this reaction proceeded via a Friedel-Crafts-type reaction pathway.

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Palladium-catalyzed intramolecular dearomative reductive-Heck reaction of C2-substituted indoles is developed, which provides access to structurally diverse 3,2'-spiropyrrolidine oxindoles. By changing the hydride source to AcONa base, direct C3-arylation products [2,3-b]quinolinones are achieved in good yields. The reaction of C2-substituted benzofuran is also realized, delivering the desired spiro-product.

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A palladium-catalyzed indole dearomative bisfunctionalization via a domino arylation/alkynylation sequence has been developed, which provides a reliable approach to a series of structurally diverse tetracyclic indolines bearing vicinal tertiary and quaternary stereocenters in moderate to good yields and excellent diastereoselectivities.

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A highly enantioselective Friedel-Crafts alkylation of indoles with N-sulfonylaziridines as alkylating agents has been developed by utilizing the complex of Cu(CH3CN)4BF4/(S)-Segphos as a catalyst. A range of optically active tryptamine derivatives are obtained in good to excellent yields and enantioselectivities (up to >99% ee) via a kinetic resolution process.

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The next generation of far infrared space observatories will require extremely sensitive detectors that can be realized only by combining extremely low intrinsic noise with high optical efficiency. We have measured the broad-band optical response of ultra-sensitive transtion edge sensor (TES) bolometers (NEP≈2aW/Hz) in the 30-60-μm band where radiation is coupled to the detectors with a few-moded conical feedhorn and a hemispherical backshort. We show that these detectors have an optical efficiency of 60% (the ratio of the power detected by the TES bolometer to the total power propagating through the feedhorn).

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Aim: To discover neuroprotective compounds and to characterize the discovered active compound YQ138 as a novel GSK-3β inhibitor.

Methods: Primary rat cerebellar granule cells (CGCs) were treated with glutamate, and cell viability was analyzed with MTT assay, which was used as in vitro model for screening neuroprotective compounds. Active compound was further tested in OGD- or serum deprivation-induced neuronal injury models.

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A highly enantioselective palladium/l-proline-catalyzed α-arylative desymmetrization of cyclohexanones was developed. The new strategy for α-arylation reaction led to a series of optically active morphan derivatives bearing α-carbonyl tertiary stereocenters in good yields with excellent enantioselectivities (up to 99% ee).

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A Friedel-Crafts alkylation reaction of styrenes with trifluoropyruvates has been developed, which delivered allylic alcohols in excellent yields (up to 98%) using the Ni(ClO4)2·6H2O/bipyridine complex as a catalyst. The asymmetric reaction was catalyzed by the chiral Cu(OTf)2/bisoxazoline complex to afford the corresponding chiral allylic alcohols bearing trifluoromethylated quaternary stereogenic centers in moderate enantioselectivities (up to 75% ee).

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Highly enantioselective Friedel-Crafts C2-alkylation reactions of 3-substituted indoles with α,β-unsaturated esters and nitroalkenes were developed using chiral Lewis acids as catalysts, which afforded chiral indole derivatives bearing C2-benzylic stereogenic centers in good to excellent yields (up to 99%) and enantioselectivities (up to 96% ee).

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The enantioselective redox annulation of nitroalkynes with indoles is enabled by gold/chiral phosphoric acid dual catalysis. A range of indolin-3-one derivatives bearing quaternary stereocenters at the C2 position were afforded in good yields and excellent enantioselectivities (up to 96 % ee) from readily available starting materials.

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A novel copper/I2-mediated oxidative cross-coupling/cyclization of 2-(pyridin-2-yl)acetate derivatives and simple olefins is developed, which provides a straightforward and efficient access to structural diversely indolizines. A series of 1,3-di- and 1,2,3-trisubstituted indolizines are easily synthesized in modest to excellent yields.

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A highly enantioselective intramolecular arylative dearomatization of indoles via palladium-catalyzed reductive Heck reactions was developed. The new strategy led to a series of optically active indolines bearing C2-quaternary stereocenters in modest to good yields with excellent enantioselectivities (up to 99% ee).

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Article Synopsis
  • The generation of optical frequency combs from quantum cascade lasers has gained significant interest recently.
  • Fast detectors are utilized to demonstrate the mutual coherence of these combs, alongside a new inequality for quantitatively assessing their performance.
  • Technical challenges in shifted wave interference Fourier Transform spectroscopy (SWIFTS) are discussed, revealing how it can help analyze the time-domain properties of the combs, which display characteristics of both frequency and amplitude modulation.
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A palladium-catalyzed three-component cascade reaction of 2-(2-enynyl)pyridines with nucleophiles and allyl halides has been developed, enabling the synthesis of densely functionalized indolizines in moderate to good yields. The newly developed methodology offers several practical advantages, including operational simplicity, ready availability of starting materials, and mild reaction conditions.

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We developed two efficient protocols for the synthesis of feruloyl and caffeoyl derivatives from commercial vanillin and veratraldehyde. Pharmacological activities were assessed against a panel of human cancer cell lines in vitro. Most synthesized compounds demonstrated attractive cytotoxicity.

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