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Metal phthalocyanine molecules with Me-N4 centers have shown promise in electrocatalytic CO2 reduction (eCO2R) for CO generation. However, iron phthalocyanine (FePc) is an exception, exhibiting negligible eCO2R activity due to a higher CO2 to *COOH conversion barrier and stronger *CO binding energy. Here, amine functional groups onto atomic-Fe-rich carbon dots (Af-Fe-CDs) are introduced via a one-step solvothermal molecule fusion approach. Af-Fe-CDs feature well-defined Fe-N4 active sites and an impressive Fe loading (up to 8.5 wt%). The synergistic effect between Fe-N4 active centers and electron-donating amine functional groups in Af-Fe-CDs yielded outstanding CO2-to-CO conversion performance. At industrial-relevant current densities exceeding 400 mA cm-2 in a flow cell, Af-Fe-CDs achieved >92% selectivity, surpassing state-of-the-art CO2-to-CO electrocatalysts. The in situ electrochemical FTIR characterization combined with theoretical calculations elucidated that Fe-N4 integration with amine functional groups in Af-Fe-CDs significantly reduced energy barriers for *COOH intermediate formation and *CO desorption, enhancing eCO2R efficiency. The proposed synergistic effect offers a promising avenue for high-efficiency catalysts with elevated atomic-metal loadings.
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A novel, to the best of our knowledge, structure for spectral beam combining (SBC) is proposed, utilizing a polarization-separated feedback (PSF). A polarization separation element is introduced to separate the laser beam into a TE-polarized light and a TM-polarized light. The lower-power light is selected as the external feedback to adjust the resonant wavelength, while the other light is combined spectrally. Compared to the conventional SBC source with a similar feedback, the power and efficiency of the PSFSBC are improved by approximately 20%. Additionally, the beam quality in the non-SBC direction is optimized by 10%, and the power on the output coupler is reduced to nearly one-third. This provides an effective method for achieving an optimized SBC performance.
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Zintl compounds have continuously received significant attention, primarily due to their structural characteristics that align with the properties of the electron crystal and phonon glass. In this study, the crystal structure and thermoelectric properties of the quaternary Zintl chalcogenide BaScCuTe3 are investigated. The band structure calculations for BaScCuTe3 reveal a slight energy split of 0.08 eV between the second valence band and the valence band maximum, suggesting the presence of multiband-transport behaviors. Substitution of rare earth Gd for Sc is conducted, which significantly increases the hole concentration from 4.1 × 1019 cm-3 to 8.2 × 1019 cm-3 at room temperature. Meanwhile, the Seebeck coefficient increases because of the participation of the second valence band. A maximum power factor of 6.56 µW/cm·K2 at 773 K is obtained, which is 72% higher than that of the pristine sample. Moreover, the lattice thermal conductivity decreases from 0.57 W/m·K for BaScCuTe3 to 0.48 W/m·K for BaSc0.97Gd0.03CuTe3 at 773 K, owing to the introduction of point-defect scattering. As a result, there is a noteworthy improvement in the thermoelectric figure of merit zT, increasing from 0.44 for the undoped sample to 0.85 for BaSc0.98Gd0.02CuTe3. Considering these findings, BaScCuTe3 exhibits great potential and holds promise for further investigation in the field of thermoelectric materials.
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Blue lasers are integral to a variety of applications, including marine communication, underwater resource exploration, cold laser processing, laser medicine, and beyond. Vertical external cavity surface-emitting lasers (VECSELs) have the advantages of high output power and tunable wavelength, and can output blue laser via frequency doubling. In this article, a new type of intracavity beam control external-cavity structure is introduced. The laser beam waist is effectively adjusted by intracavity beam control, and the frequency conversion efficiency is improved. A laser cavity stability analysis model was developed to investigate the impact of laser cavity lens parameters and relative positions on stability. The external resonant cavity of VECSELs utilizes two optical lenses to position the beam waist near the laser output coupling mirror and locates the frequency doubling crystal at a high optical power density position to optimize frequency conversion efficiency. The VECSEL straight external-cavity structure achieves a frequency conversion efficiency of up to 60.2% at 488 nm, yielding a blue laser output exceeding 1.3 W. The full width at half maximum of the 488 nm spectrum measures approximately 0.23 nm. This intracavity beam-controlled direct external-cavity structure effectively mitigates laser mode leakage and shows potential for the development of an efficient and compact blue laser source.
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In this study, a novel metal-dielectric film mode filter structure that can flexibly regulate the transverse mode inside vertical-cavity surface-emitting lasers (VCSELs) is proposed. The number, volume, and stability of transverse modes inside the VCSEL can be adjusted according to three key parameters-the oxide aperture, the metal aperture, and the distance between the oxide aperture and the metal aperture-to form a flexible window, and a new parameter is defined to describe the mode identification. This study provides a complete simulation theory basis and calculation method, which is of great significance for the optical mode control in VCSELs.
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BACKGROUND: Microvascular complications are associated with an overtly increased risk of adverse outcomes in patients with diabetes including coronary microvascular injury which manifested as disruption of adherens junctions between cardiac microvascular endothelial cells (CMECs). However, particular mechanism leading to diabetic coronary microvascular hyperpermeability remains elusive. METHODS: Experimental diabetes was induced in mice with adipose tissue-specific Adipsin overexpression (AdipsinLSL/LSL-Cre) and their respective control (AdipsinLSL/LSL). In addition, cultured CMECs were subjected to high glucose/palmitic acid (HG + PA) treatment to simulate diabetes for a mechanistic approach. RESULTS: The results showed that Adipsin overexpression significantly reduced cardiac microvascular permeability, preserved coronary microvascular integrity, and increased coronary microvascular density. Adipsin overexpression also attenuated cardiac dysfunction in diabetic mice. E/A ratio, an indicator of cardiac diastolic function, was improved by Adipsin. Adipsin overexpression retarded left ventricular adverse remodeling, enhanced LVEF, and improved cardiac systolic function. Adipsin-enriched exosomes were taken up by CMECs, inhibited CMECs apoptosis, and increased CMECs proliferation under HG + PA treatment. Adipsin-enriched exosomes also accelerated wound healing, rescued cell migration defects, and promoted tube formation in response to HG + PA challenge. Furthermore, Adipsin-enriched exosomes maintained adherens junctions at endothelial cell borders and reversed endothelial hyperpermeability disrupted by HG + PA insult. Mechanistically, Adipsin blocked HG + PA-induced Src phosphorylation (Tyr416), VE-cadherin phosphorylation (Tyr685 and Tyr731), and VE-cadherin internalization, thus maintaining CMECs adherens junctions integrity. LC-MS/MS analysis and co-immunoprecipitation analysis (Co-IP) unveiled Csk as a direct downstream regulator of Adipsin. Csk knockdown increased Src phosphorylation (Tyr416) and VE-cadherin phosphorylation (Tyr685 and Tyr731), while abolishing Adipsin-induced inhibition of VE-cadherin internalization. Furthermore, Csk knockdown counteracted Adipsin-induced protective effects on endothelial hyperpermeability in vitro and endothelial barrier integrity of coronary microvessels in vivo. CONCLUSIONS: Together, these findings favor the vital role of Adipsin in the regulation of CMECs adherens junctions integrity, revealing its promises as a treatment target against diabetic coronary microvascular dysfunction. Graphical abstract depicting the mechanisms of action behind Adipsin-induced regulation of diabetic coronary microvascular dysfunction.
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Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Camundongos , Animais , Cardiomiopatias Diabéticas/genética , Diabetes Mellitus Experimental/complicações , Células Endoteliais , Fator D do Complemento/farmacologia , Cromatografia Líquida , Espectrometria de Massas em Tandem , Células CultivadasRESUMO
The mechanisms of the effect of propionate metabolism and immunity on nonalcoholic fatty liver disease (NAFLD) have not been adequately studied. Firstly, differentially expressed-propionate metabolism-related genes (DE-PMRGs) were selected by overlapping PMRGs and differentially expressed genes (DEGs) between the simple steatosis (SS) and health control (HC) groups. Then, common genes were selected by overlapping DE-PMRGs and key module genes obtained from weighted gene co-expression network analysis (WGCNA). Subsequently, the biomarkers were screened out by machine learning algorithms. The expression of the biomarkers was validated by quantitative Real-time PCR. In total, 5 biomarkers (JUN, LDLR, CXCR4, NNMT, and ANXA1) were acquired. The nomogram constructed based on 5 biomarkers had good predictive power for the risk of SS. Next, 5 biomarkers, 11 miRNAs, and 149 lncRNAs were encompassed in the ceRNA regulatory network. The expression of biomarkers was significantly higher in the HC group than in the SS group, which was consistent with the results in the GSE89632 and GSE126848 datasets. In this study, 5 immune and propionate metabolism-related biomarkers (JUN, LDLR, CXCR4, NNMT, and ANXA1) were screened out to provide a basis for exploring the prediction of diagnosis of NAFLD.
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Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/genética , Propionatos , Algoritmos , Biomarcadores , Perfilação da Expressão GênicaRESUMO
PI3Kδ inhibitors play an important role in the treatment of leukemia, lymphoma and autoimmune diseases. Herein, using our reported compounds as the lead compound, we designed and synthesized a series of selenium-containing PI3Kδ inhibitors based on quinazoline and pyrido[3,2-d]pyrimidine skeletons. Among them, compound Se15 showed sub-nanomolar inhibition against PI3Kδ and strong δ-selectivity. Moreover, Se15 showed potent anti-proliferative effect on SU-DHL-6 cells with an IC50 value of 0.16 µM. Molecular docking study showed that Se15 was able to form multiple hydrogen bonds with PI3Kδ and was close proximity and stacking with PI3Kδ selective region. In conclusion, the Se-containing compound Se15 bearing pyrido[3,2-d]pyrimidine scaffold is a novel potent and selective PI3Kδ inhibitor. The introduction of selenium can enrich the structure of PI3Kδ inhibitors and provide a new idea for design of novel PI3Kδ inhibitors.
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Classe I de Fosfatidilinositol 3-Quinases , Leucemia , Selênio , Humanos , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Pirimidinas/farmacologia , Selênio/química , Selênio/farmacologia , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Desenho de FármacosRESUMO
Damping is an important factor contributing to errors in the measurement of rotational inertia using the torsion pendulum method. Identifying the system damping allows for minimizing the measurement errors of rotational inertia, and accurate continuous sampling of torsional vibration angular displacement is the key to realizing system damping identification. To address this issue, this paper proposes a novel method for measuring the rotational inertia of rigid bodies based on monocular vision and the torsion pendulum method. In this study, a mathematical model of torsional oscillation under a linear damping condition is established, and an analytical relationship between the damping coefficient, torsional period, and measured rotational inertia is obtained. A high-speed industrial camera is used to continuously photograph the markers on a torsion vibration motion test bench. After several data processing steps, including image preprocessing, edge detection, and feature extraction, with the aid of a geometric model of the imaging system, the angular displacement of each frame of the image corresponding to the torsion vibration motion is calculated. From the characteristic points on the angular displacement curve, the period and amplitude modulation parameters of the torsion vibration motion can be obtained, and finally the rotational inertia of the load can be derived. The experimental results demonstrate that the proposed method and system described in this paper can achieve accurate measurements of the rotational inertia of objects. Within the range of 0-100 × 10-3 kg·m2, the standard deviation of the measurements is better than 0.90 × 10-4 kg·m2, and the absolute value of the measurement error is less than 2.00 × 10-4 kg·m2. Compared to conventional torsion pendulum methods, the proposed method effectively identifies damping using machine vision, thereby significantly reducing measurement errors caused by damping. The system has a simple structure, low cost, and promising prospects for practical applications.
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Halogenated sesquiterpenes are important derivatives of sesquiterpenes, referring to chemical components of sesquiterpenes that contain halogens such as chlorine, bromine, and iodine. Halogenated sesquiterpenes have attracted attention from researchers in China and abroad because of their diverse structures, unique halogen elements, and extensive pharmacological activities. Studies have shown that halogenated sesquiterpenes exhibit significant antimicrobial, anti-inflammatory, anticancer, insecticidal, hypoglycemic, and enzyme inhibitory activities. In order to better explore the potential pharmaceutical value of halogenated sesquiterpenes, this paper reviewed the structural characteristics and pharmacological activities of halogenated sesquiterpenes in the past two decades, aiming to provide references for further research and development of this class of compounds.
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Sesquiterpenos , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Anti-Inflamatórios/farmacologia , ChinaRESUMO
Many Zintl phases are promising thermoelectric materials owning to their features like narrow band gaps, multiband behaviors, ideal charge transport tunnels, and loosely bound cations. Herein we show a new Zintl phase NaCdSb with exceptional intrinsic thermoelectric performance. Pristine NaCdSb exhibits semiconductor behaviors with an experimental hole concentration of 2.9×1018 â cm-3 and a calculated band gap of 0.5â eV. As the temperature increases, the hole concentration rises gradually and approaches its optimal one, leading to a high power factor of 11.56â µW cm-1 K-2 at 673â K. The ultralow thermal conductivity is derived from the small phonon group velocity and short phonon lifetime, ascribed to the structural anharmonicity of Cd-Sb bonds. As a consequence, a maximum zT of 1.3 at 673â K has been achieved without any doping optimization or structural modification, demonstrating that NaCdSb is a remarkable thermoelectric compound with great potential for performance improvement.
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An extended spectral beam combining (SBC) configuration that folds the optical path of the combining laser into the non-SBC direction and doubly narrows the SBC spectrum by introducing a right angular prism is proposed. Similar combined power and beam quality but half of the spectral width and a smaller size are demonstrated by comparing the standard SBC with the proposed SBC of the same 800nm laser bar. It provides an effective way to miniaturize the SBC size, improve the SBC stability and compress the SBC spectrum simultaneously. As far as we know, this study is also the first to report on folding the SBC optical path to the non-SBC direction, which provides a new idea for the SBC source.
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A method of compressing spectral bandwidth in spectral beam combining (SBC) of quantum cascade lasers (QCLs) by multiplexing a pair of blazed gratings arranged in a V-shaped configuration is proposed. The spectral interval can be compressed by increasing the number of diffractions via the round-trip propagation between gratings. Experimental results show that the SBC spectral interval of three diffractions is narrowed to 1/3 that of a single diffraction. The SBC power can be further improved within a given spectrum range by increasing the number of QCLs, which provides a feasible scheme to scale the SBC power and the brightness of QCLs.
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We characterize laser generation in an ultralong air cavity (several meters in length) using an optical-pumped semiconductor gain chip for laser wireless charging applications. The study realizes laser generation in an external air cavity with a length of 200 cm, for the first time, and achieves a maximum output laser power of more than 86.3 mW. Furthermore, the laser oscillation can be maintained even when the output mirror of laser is off-axis within 1.6 cm. Thus, a long external cavity laser would ease the alignment between the laser beam and charging terminal, making it suitable for laser wireless charging applications.
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Contrast-induced nephropathy (CIN) is a common complication with adverse outcome after iodinated-contrast injection, yet still lacking effective medication. Heme oxygenase-1 (HO-1) has been reported to play an important role against renal injuries. Hemin, a HO-1 inducer and anti-porphyria medicine, may have a promising effect against CIN. In this study, we aim to investigate the effect of hemin on CIN model and the underlying molecular mechanisms in human proximal tubule epithelial cells (HK-2). To mimic a common condition in percutaneous coronary intervention (PCI) patients, CIN was induced by intravenous iopromide in high-fat fed diabetic rats. We found hemin, given right before iopromide, mitigated CIN with enhanced antioxidative capacity and reduced oxidative stress. HK-2 cells insulted by iopromide demonstrated decreased cell vitality and rising reactive oxygen species (ROS), which could also be inhibited by hemin. The effects of hemin involved a key molecule in ferroptosis, glutathione peroxidase (GPX4), whose down-expression by small interfering RNA (siRNA) reversed the effect of hemin on HK-2 cells. Furthermore, hemin's induction of GPX4 involved HO-1 and nuclear factor erythroid 2-related factor 2 (Nrf2). Either HO-1 or Nrf2 inhibitor prevented hemin's effect on GPX4 to a comparable extent, and over-expression of Nrf2 increased GPX4 expression. Moreover, intervention of ferroptosis inhibitor liproxstatin-1 also alleviated CIN in vivo. Therefore, we showed hemin mitigated CIN, inhibiting oxidative stress and ferroptosis, by upregulation of GPX4 via activation of HO-1/Nrf2. Hemin, as a clinical medicine, has a translational significance in treating CIN, and anti-ferroptosis is a potential therapeutic strategy for CIN.
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Meios de Contraste , Células Epiteliais , Ferroptose , Fármacos Hematológicos , Hemina , Nefropatias , Animais , Células Cultivadas , Meios de Contraste/efeitos adversos , Diabetes Mellitus Experimental/etiologia , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Ferroptose/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Fármacos Hematológicos/farmacologia , Heme Oxigenase-1/metabolismo , Hemina/farmacologia , Humanos , Nefropatias/induzido quimicamente , Nefropatias/tratamento farmacológico , Nefropatias/metabolismo , Nefropatias/prevenção & controle , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/fisiopatologia , Fator 2 Relacionado a NF-E2/metabolismo , Intervenção Coronária Percutânea , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , RNA Interferente Pequeno/genética , Ratos , Transdução de SinaisRESUMO
Liver fibrosis results from liver inflammation and progresses to liver cirrhosis or liver cancer. It is known that nonalcoholic liver disease is mediated by the Toll-like receptor 4 (TLR4)/myeloid differentiation factor-2 (MD-2)-tumor necrosis factor-alpha (TNF-α) signaling pathway. This study aimed to investigate whether alcoholic liver disease is also mediated by this pathway. To this end, we first established rat models of liver fibrosis by administering alcohol. Next, the rats were injected with anti-TLR4 and anti-MD-2 antibodies. Real Time Quantitative PCR (RT-qPCR) and Western blotting were used to detect the activation of the TLR4/MD-2-TNF-α signaling pathway and hepatic stellate cells (HSCs). Moreover, the expression of molecules related to liver fibrosis was estimated. The morphology of rat liver tissue was observed through hematoxylin-eosin staining and Masson staining. For in vitro studies, Kupffer cells (KCs) isolated from the liver were transfected with si-TLR4 and si-MD-2 and co-cultured with HSCs to determine the activity of HSCs. It was found that alcohol treatment activated the TLR4/MD-2-TNF-α signaling pathway and upregulated the molecules associated with liver fibrosis. However, inhibition of TLR4 and MD-2 partially reversed this trend. Notably, in vitro studies indicated that knockdown of TLR4 and MD-2 in KCs partially inhibited LPS-induced activation of KCs and HSCs. Overall, this study showed that alcohol induces liver fibrosis via the LPS-TLR4/MD-2-TNF-α signaling pathway.
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OBJECTIVE: The objective of this study was to review evidence on the effectiveness of vaccination in the prevention of human papilloma virus (HPV) infection at the cervix, anal, and oral. STUDY DESIGN: Systematic review and meta-analysis. METHODS: The key search limitations are as follows: "Human Papilloma Virus", "Papilloma Virus, Human" "Human Papillomavirus Virus", "HPV" and "oral", "anus", "anal", "penis", "cervical," and "vaccine". Randomized controlled studies were searched and analyzed the risk ratio by Review Manager 5.3; funnel plot was adopted for publication bias analysis. RESULTS: Five randomized controlled studies enrolling 13,686 participants were retrieved, analyzed, and showed that HPV vaccination can effectively block HPV infection at cervical, anal, and oral. Subgroup analysis, moreover, proved that HPV 16/18 is more effective than HPV 6/11/16/18 in preventing anal and oral infections. CONCLUSION: HPV vaccine is efficacious in preventing HPV infection not only at cervical but also at anal and oral, as evidence supported by relevant studies.
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Infecções por Papillomavirus , Vacinas contra Papillomavirus , Feminino , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Humanos , Papillomaviridae , Infecções por Papillomavirus/prevenção & controle , VacinaçãoRESUMO
In this paper we reported on the optically pumped VECSELs with switchable lasing wavelengths. The two lasing wavelengths of λ ≈ 954â nm and 1003â nm are generated at different pumping powers from the same gain chip. The thermal rollover of output power is observed twice, and the first rollover on the power curve indicates the switch of lasing wavelength. During the operation of our VECSEL, the increase of pumping power changes the temperature within the gain chip, and thus the gain spectrum is tuned to the one of two modes, which is defined by the dips on the reflectivity spectrum. The maximum output power of each wavelength exceeds 2.2 W at -5 °C. The dual-wavelength emission at λ ≈954â nm and 1003â nm is also demonstrated, and the output power of the dual-wavelength emission reached nearly 2 W.
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In this study, UC rat model was established by administration of 5% (w/v) dextran sulfate sodium, and the pharmacokinetics of verapamil and norverapamil were evaluated in normal and UC rats using UPLC-MS/MS after oral administration of 5 mg/kg and 50 mg/kg verapamil.The peak concentration (Cmax) and the area under plasma concentration-time curves (AUC) of verapamil in UC rats after oral administration of 5 mg/kg were significantly greater (2.5 times and 2 times, respectively) than those in normal rats, but the clearance rate (Cl) was significantly lower (by 50%). For norverapamil, Cmax and AUC were significantly greater (2.8 times and 2.5 times, respectively), and Cl was significantly lower (by 45%). But, pharmacokinetic parameters of verapamil and norverapamil after oral administration of 50 mg/kg were no significant differences between UC and normal rats.The better absorption and poor excretion for low-dose verapamil may be attributed to down-regulation of P-gp expression in the intestine and kidney. No significant differences of pharmacokinetic parameters for high-dose verapamil may be explained as the saturation of an efflux mechanism.The findings of this study suggested that in UC patients, doses of verapamil should be decreased when low-dose verapamil was orally administrated.