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关键词： 1,3-Aminofluorination   Copper(II)-Catalyzed   High diastereoselectivity   γ-Fluoramine  

摘要： 1,3-aminofluorinations as a powerful strategy to synthesize γ-fluoroamines are in urgent need of development. Herein, a copper(II)-catalyzed 1,3-aminofluorination of spirovinylcyclopropyl oxindoles and N-fluorobenzenesulfonimide (NFSI) was realized. The protocol enables access to γ-fluoroamines containing oxindole in moderate to good yields (up to 75%) with high diastereoselectivity (all >20:1 dr). Notably, TMSCN as an additive enhances the reaction effect rather than the traditional cyanation reagent. Based on experimental results and the free radical capture experiments, a plausible reaction mechanism has been proposed, revealing the reason why TMSCN promotes the reaction.

关键词： Autoimmune disease   Antigen   Immune tolerance   Antigen-specific immunotherapy   Immune reprogramming   APC   Antigen presenting cells   AS   Alternative splicing   ASI   ATG   Anti-thymocyte globulin   CAR   Chimeric antigen receptor   Chrg   Chromogranin   DC   Dendritic cell   DRiP   Defective ribosomal product   ER   Endoplasmic reticulum   GABA   Gamma-aminobutyric acid   GADA   Glutamic acid decarboxylase autoantibodies   GAD   Glutamic acid decarboxylase   GIT   Gastrointestinal tract   GRP78   Glucose-regulated protein 78   HLA   Human leukocyte antigen   HIP   Hybrid insulin peptide   IAA   Insulin autoantibodies   IA-2   Insulinoma-associated protein 2   IA-2A   Insulinoma-associated protein autoantibodies   IAPP   Islet amyloid polypeptide   IGRP   Islet-specific glucose-6-phosphatase catalytic subunit-related protein   IFN-γ   Interferon-γ   INS   Insulin   IL   Interleukin   IL2RA   Interleukin-2 receptor alpha   LADA   Latent autoimmune diabetes   mAb   Monoclonal antibody   MHC   Major histocompatibility complex   NET   Neutrophil extracellular trap   NLRP3   NOD-, LRR, and PYD domains-containing protein 3   NK   Natural killer   NOD   Non-obese diabetic   NPY   Neuropeptide Y   PAD   Peptidyl arginine deiminase   PEG   Polyethylene glycol   PI   Proinsulin   PLGA   Poly(lactic-co-glycolic acid)   PLN   Pancreatic draining lymph node   PPI   Preproinsulin   PS   Phosphatidylserine   PTM   Post-translational modification   PTP   Protein tyrosine phosphatase-like   pTreg   peripheral regulatory T cell   RA   Retinoic acid   ROS   Reactive oxygen species   T1D   Type 1 diabetes   Tfh   T follicular helper   TGF-β   Transforming growth factor-β   TGM2   Transglutaminase 2   TLR   Toll-like receptor   TNF-α   Tumor necrosis factor-α   tolDC   Tolerogenic dendritic cell   Treg   Regulatory T cells   tTG   Tissue transglutaminase   tTreg   thymus-derived regulatory T cell   ZnT8   Zinc transporter 8   VNTR   variable number of tandem repeat  

摘要：

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  Antigen selection is not straightforward and likely evolves with disease.
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  Current antigen formulations are limited, but next-generation delivery systems offer new opportunities.
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  Single-antigen approaches may be insufficient in a complex and evolving autoimmune response.
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  Multi-omics approaches can decode stage-specific disease biology.
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  Biomarkers will become essential to guide both patient selection and treatment monitoring.

关键词： CTAO   LST-1   MAGIC   Trigger   Stereoscopy   Cherenkov   Gamma-ray  

摘要： We present the implementation and validation of a hardware stereoscopic trigger (HaST) linking the Large-Sized Telescope prototype (LST-1) of the Cherenkov Telescope Array Observatory (CTAO) with the MAGIC (Major Atmospheric Gamma-ray Imaging Cherenkov Telescope) telescopes at the Roque de los Muchachos Observatory. This setup enables real-time exchange of camera-level trigger signals, allowing joint data acquisition and providing a commissioning platform for the future 4-LST HaST system.

关键词： Zn1-x-ySnxCuyO   Solid state reaction   Thermistor   Electrical properties   Nanoceramics  

摘要：

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  Zn_1-x-ᵧSn_xCuᵧO nanoceramics synthesized via solid-state reaction.
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  Single-phase wurtzite ZnO structure confirmed; crystallite size reduced to 44.5 nm.
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  Co-doping increases microstrain and suppresses grain growth.
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  Strong NTC thermistor behaviour with β up to 14,508 K and Ea = 1.25 eV.
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  Sn/Cu ratio tunes electrical conductivity for thermistor optimization.

摘要： Optical transmission systems are increasingly confronted with the challenge of escalating data rates approaching the Shannon limit, underscoring the need for L-band. The integration of high-gain, low-noise figure (NF) discrete Raman amplifiers (DRAs) is crucial for ensuring transmission stability in long-distance systems. Nevertheless, the performance of DRAs has long been constrained by limitations in the gain fiber characteristics. This work focuses on the synergistic optimization of material properties and waveguide geometry to design a germanium-doped photonic crystal fiber featuring a graded-index profile (GI-Ge-PCF) based on the Finite Element Method (FEM). Utilizing Plasma Chemical Vapor Deposition (PCVD) combined with the stack-and-draw technique, we fabricated a high Raman gain photonic crystal fiber at 1550 nm featuring a high nonlinear coefficient (γ) of 26.7 W⁻¹·km⁻¹, a high Raman gain coefficient of 15.5 W⁻¹·km⁻¹, and a low attenuation of 1.21 dB/km, representing the best-reported for germanium-core PCF to date. A backward-pumped DRA was implemented, utilizing only 800 m fibers. It was pumped at wavelengths of 1469 nm, 1493 nm, and 1510 nm with a total power of 1.6 W. Across the 1575-1627 nm band, the experimental setup exhibited a gain exceeding 23.91 dB (average of 25.679 dB) and a gain flatness of 2.416 dB, along with a noise figure (NF) of 4.824 dB. Compared to conventional germanium-doped fibers, the proposed GI-Ge-PCF exhibits superior Raman gain coefficient and reduced attenuation, which collectively contribute to significantly enhanced DRA performance in terms of both gain and NF, paving the way for the development of high-efficiency amplifiers tailored for L-band applications.

关键词： Conditional quantile   Cumulative quantile regression   Moment-recovered approximation   The Laplace transform inversion  

摘要： In this work, the moment-recovered approach for approximating the conditional distribution, conditional quantile, regression and cumulative quantile regression functions is proposed. All these constructions are based on using the information contained either in the sequence of moments or on the scaled values of Laplace transform of underlying distributions. Simulation study is conducted to demonstrate the performance of proposed constructions.

关键词： Gas sensor   H(2)S   Openwork structure   Semiconductor metal oxide   YMn(1-x)Fe(x)O(3)  

摘要： Semiconductor metal oxides (SMOs) are widely used in gas sensing and detection due to their low cost, ease of manufacture, and portability. However, single SMO for hydrogen sulfide (H₂S) detection suffers from high operating temperatures, low sensitivity, and poor selectivity. This study focused on designing multifaceted SMO materials, and three-dimensional openwork structure YMn_1-xFe_xO₃ composites were prepared using the premixed stagnation flame method. The prepared gas sensor showed high sensitivity to H₂S gas. Specifically, the YMn_0.7Fe_0.3O₃ sensor has a maximum response value of 10.55 at an optimum operating temperature of 200 °C when exposed to 30 ppm H₂S. It also demonstrated a low detection limit of 0.94 ppm and excellent selectivity, which is advantageous for long-term practical applications. The excellent sensing performance is attributed to the three-dimensional openwork structure of the material and the successful doping of Fe³⁺ into the YMnO₃ lattice. These features increase the specific surface area, which facilitates the diffusion and adsorption of H₂S gas in the sensing layer. The YMn_1-xFe_xO₃ materials provide a viable strategy for designing highly responsive and selective SMO gas sensors for detecting H₂S.

关键词： Cement industry pollution   Semiconductor ZCTSSe-ZnCu2Sn(S1-xSex)4 alloys   Selenium doping   Photocatalytic remediation   Light adsorption   Pollutants adsorption  

摘要：

关键词： AMPK/mTOR   Autophagy   Bovine mammary epithelial cells   HO-1   Keap1/Nrf2   Oxidative damage  

摘要： Heme oxygenase-1 (HO-1) plays an important role in maintaining Nrf2-mediated redox homeostasis. Lipopolysaccharide (LPS), a major pathogenic factor in bacterial mastitis, induces oxidative stress and inflammation in bovine mammary epithelial cells (BMECs). HO-1-induced autophagy has been shown to mitigate oxidative damage across various tissues in previous studies. Therefore, we hypothesized that HO-1 may alleviate oxidative stress in BMECs by promoting autophagy via the Keap1/Nrf2 and AMPK/mTOR signaling pathways. We examined the effects of HO-1 on oxidative stress, including antioxidant enzyme production and inflammatory response, as well as autophagy in LPS-stimulated BMECs. In this study, overexpression and knockout of HO-1 or Nrf2 were performed in BMECs to verify the involvement of HO-1 in the Keap1/Nrf2 pathway. In addition, autophagy inhibitors and mTOR inhibitor were used to determine whether the antioxidant effects of HO-1 were mediated by autophagy via the AMPK/mTOR signaling pathway. We found that HO-1 alleviated LPS-induced inflammation response and improved the resistance of BMECs to oxidative stress. Furthermore, HO-1 activated the Keap1/Nrf2 signaling pathway, thereby enhancing antioxidant capacity, which was further confirmed by in vitro overexpression and knockout experiments targeting Nrf2 or HO-1. Meanwhile, HO-1 also upregulated the expression of autophagy-related genes, whereas treatment with an autophagy inhibitor attenuated the antioxidant effects of HO-1. In addition, administration of an mTOR inhibitor further indicated that HO-1-mediated autophagy was regulated via the AMPK/mTOR signaling pathway. In conclusion, HO-1 alleviates oxidative damage in BMECs by promoting autophagy through the Keap1/Nrf2 and AMPK/mTOR signaling pathways. These findings identify HO-1 as a potential therapeutic target for reducing tissue damage in bacterial mastitis.

关键词： neuroinflammation   neu rological disorders   neuroprotective mechanismsthe   limit neuroinflammationstabilize   wolfram syndromewhere   inhibit n   acute ischemic strokewhere   reduce infa rct volumethe  

摘要： Glucagon-like peptide-1 receptor agonists(GLP-1RAs),originally developed as drugs for type 2 diabetes and obesity,exhibit therapeutic effects for various neu rological disorders recently,with multiple neuroprotective mechanisms.The GLP-1RAs therapy has been applied to acute ischemic stroke,where they limit neuroinflammation,stabilize the neurovascular unit,and reduce infa rct volume.The GLP-1RAs drugs have also been tested for Wolfram syndrome,where they mitigate endoplasmic reticulum(ER) stress and inhibit neu ronal apoptosis.