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1.
Phytomedicine ; 133: 155927, 2024 Jul 29.
Article de Anglais | MEDLINE | ID: mdl-39096543

RÉSUMÉ

BACKGROUND: Moxibustion, a traditional Chinese medicine practice, employs Moxa Wool, derived from Artemisia argyi. Flavonoids, the key pharmacological constituents in Moxa Wool, are known for their anti-inflammatory and analgesic properties. The purity of Moxa Wool, particularly its flavonoid content, directly influences the efficacy of moxibustion treatments. However, quantifying these bioactive flavonoids accurately and non-destructively has been a challenge. PURPOSE: This study introduces terahertz spectroscopy as a non-destructive optical detection method for qualitative detection and quantitative analysis of flavonoids in Moxa Wool. By establishing a mathematical model between spectral signals and clinical efficacy, a reliable correlation between flavonoid concentration and the therapeutic effect of moxibustion can be established, providing a potential predictive model for the treatment outcomes of rheumatoid arthritis. STUDY DESIGN: We adopted terahertz spectroscopy technology and combined it with terahertz metamaterial biosensors to achieve rapid, efficient, and non-destructive testing of the quality of Moxa Wool. This method reduces the detection time from hours to minutes while lowering the sample detection limit, overcoming the limitations of traditional detection methods in pharmacological research. METHODS: Through terahertz metamaterial biosensors, rapid detection of the purity of Moxa Wool has been achieved. A combination of molecular simulation and terahertz spectroscopy was used to quantitatively analyze the flavonoid content in different purities of Moxa Wool. To ensure accuracy, the quantitative results of flavonoids obtained by terahertz spectroscopy were validated using high-performance liquid chromatography (HPLC). In addition, moxibustion treatment was performed on rats with rheumatoid arthritis using Moxa Wool, and medical indicator information was recorded. A mathematical analysis model was established to evaluate the correlation between flavonoid content and analgesic and anti-inflammatory effects. RESULTS: Terahertz spectroscopy analysis shows that there is a direct correlation between the flavonoid content in moxibustion and the absorption peak intensity. The maximum R2 in the model analysis is 0.98, indicating a high accuracy in predicting the purity of Moxa Wool. These results were also validated by HPLC. In a rat model, the purity of 30:1 Moxa Wool samples showed a 50 % decrease in TNF-α, IL-1ß, and IL-6 levels during treatment compared to low-purity samples, significantly reducing inflammation markers and pain symptoms. Meanwhile, The PLS prediction model established a correlation between terahertz-detected flavonoid levels and treatment outcomes (PWL and IL-1ß). The maximum R2 in the model is 0.91, indicating a high correlation between flavonoid levels and the anti-inflammatory and analgesic effects of moxibustion treatment. CONCLUSION: This study not only demonstrates the effectiveness of terahertz spectroscopy in the pharmacological quantification of bioactive compounds but also establishes a novel predictive model for the efficacy of moxibustion in rheumatoid arthritis treatment. It underscores the potential of integrating traditional medicine insights with advanced technology to enhance therapeutic strategies in pharmacology.

2.
Nat Commun ; 15(1): 6857, 2024 Aug 10.
Article de Anglais | MEDLINE | ID: mdl-39127772

RÉSUMÉ

In tactile sensing, decoding the journey from afferent tactile signals to efferent motor commands is a significant challenge primarily due to the difficulty in capturing population-level afferent nerve signals during active touch. This study integrates a finite element hand model with a neural dynamic model by using microneurography data to predict neural responses based on contact biomechanics and membrane transduction dynamics. This research focuses specifically on tactile sensation and its direct translation into motor actions. Evaluations of muscle synergy during in -vivo experiments revealed transduction functions linking tactile signals and muscle activation. These functions suggest similar sensorimotor strategies for grasping influenced by object size and weight. The decoded transduction mechanism was validated by restoring human-like sensorimotor performance on a tendon-driven biomimetic hand. This research advances our understanding of translating tactile sensation into motor actions, offering valuable insights into prosthetic design, robotics, and the development of next-generation prosthetics with neuromorphic tactile feedback.


Sujet(s)
Toucher , Humains , Toucher/physiologie , Main/physiologie , Phénomènes biomécaniques , Force de la main/physiologie , Perception du toucher/physiologie , Muscles squelettiques/physiologie , Rétroaction sensorielle/physiologie , Modèles neurologiques , Robotique , Mâle
3.
J Int Med Res ; 52(8): 3000605241259764, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39142703

RÉSUMÉ

Nodular fasciitis (NF) is a benign and self-limiting fibroblastic proliferation that originates from the superficial fascia and extends into the subcutaneous tissue or muscle. It typically manifests in individuals aged 20 to 35 years, with rare occurrences observed in patients over the age of 60 years. We herein report a case involving a 75-year-old man with NF in the right vocal cord. The patient sought medical attention at the Department of Otolaryngology of our hospital because of a 1-month history of hoarseness and breathlessness. The diagnosis was unable to be confirmed through preoperative pathological examination. After admission to our hospital, various examinations were completed and surgical treatment was performed, and the postoperative histopathological findings revealed the presence of NF in the right vocal cord. NF of the vocal cord is a rare clinical entity. Given its rapid progression and propensity for marked infiltration, it often poses diagnostic challenges because it can mimic various malignant soft tissue tumors. Therefore, thorough exclusion of other neoplastic lesions is imperative prior to confirming the diagnosis of NF through pathological examination. Local surgical resection remains the primary treatment modality.


Sujet(s)
Fasciite , Humains , Mâle , Fasciite/diagnostic , Fasciite/chirurgie , Fasciite/anatomopathologie , Sujet âgé , Plis vocaux/anatomopathologie , Plis vocaux/chirurgie , Enrouement/étiologie , Enrouement/diagnostic , Diagnostic différentiel
4.
Adv Sci (Weinh) ; : e2406571, 2024 Aug 09.
Article de Anglais | MEDLINE | ID: mdl-39119949

RÉSUMÉ

Janus metasurfaces, exemplifying two-faced 2D metamaterials, have shown unprecedented capabilities in asymmetrically manipulating the wavefront of electromagnetic waves in both forward and backward propagating directions, enabling novel applications in asymmetric information processing, security, and signal multiplexing. However, current Janus metasurfaces only allow for directional phase manipulation, hindering their broader application potential. Here, the study proposes a versatile Janus metasurface platform that can directionally control the phase and polarization of terahertz waves by integrating functionalities of half-wave plates, quarter-wave plates, and metallic gratings within a cascaded metasurface structure. As a proof-of-principle, the study experimentally demonstrates Janus metasurfaces capable of independent and simultaneous control over phase and polarization, showcasing propagation direction-encoded focusing and polarization conversion. Moreover, the directionally focused points are utilized with distinct polarization states for advanced applications in direction- and polarization-sensitive detection and imaging. This unique strategy for simultaneous phase and polarization control with direction-dependent versatility opens new avenues for designing ultra-compact devices with significant implications in imaging, encryption, and data storage.

5.
Chemosphere ; 362: 142750, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38960049

RÉSUMÉ

Erythrogram, despite its prevalent use in assessing red blood cell (RBC) disorders and can be utilized to evaluate various diseases, still lacks evidence supporting the effects of per- and polyfluoroalkyl substances (PFASs) and organophosphate esters (OPEs) on it. A cross-sectional study involving 467 adults from Shijiazhuang, China was conducted to assess the associations between 12 PFASs and 11 OPEs and the erythrogram (8 indicators related to RBC). Three models, including multiple linear regression (MLR), sparse partial least squares regression, and Bayesian kernel machine regression (BKMR) were employed to evaluate both the individual and joint effects of PFASs and OPEs on the erythrogram. Perfluorohexane sulfonic acid (PFHxS) showed the strongest association with HGB (3.68%, 95% CI: 2.29%, 5.10%) when doubling among PFASs in MLR models. BKMR indicated that PFASs were more strongly associated with the erythrogram than OPEs, as evidenced by higher group posterior inclusion probabilities (PIPs) for PFASs. Within hemoglobin and hematocrit, PFHxS emerged as the most significant component (conditional PIP = 1.0 for both). Collectively, our study emphasizes the joint effect of PFASs and OPEs on the erythrogram and identified PFASs, particularly PFHxS, as the pivotal contributors to the erythrogram. Nonetheless, further investigations are warranted to elucidate the underlying mechanisms.


Sujet(s)
Esters , Organophosphates , Humains , Adulte , Chine , Femelle , Études transversales , Mâle , Fluorocarbones , Adulte d'âge moyen , Érythrocytes/effets des médicaments et des substances chimiques , Exposition environnementale/statistiques et données numériques , Polluants environnementaux/analyse , Théorème de Bayes , Jeune adulte , Peuples d'Asie de l'Est , Acides sulfoniques
6.
Braz J Otorhinolaryngol ; 90(5): 101450, 2024 Jun 08.
Article de Anglais | MEDLINE | ID: mdl-39053162

RÉSUMÉ

OBJECTIVES: To investigate prognostic factors in patients with head and neck Mucoepidermoid Carcinoma (MEC), especially the impact of treatment modalities on survival. METHODS: Patients with primary head and neck MEC between 2000 and 2015 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Prognostic factors related to Overall Survival (OS) and Cancer-Specific Survival (CSS), as well as the impact of treatments, were evaluated by multivariable Cox regression analysis. RESULTS: We identified 2692 patients diagnosed with head and neck MEC, of whom 1397 (51.89%) had a parotid gland primary, 569 (22.14%) died, and 341 (12.67%) died of MEC. Older age (≥53 years), males, unmarried, lower income, tumor site in other head and neck areas, higher tumor grade, larger tumor size, and higher stage were related to poorer OS and CSS. Patients who did not undergo surgery (HR=3.20, 95% CI 2.45‒4.18) had worse OS, while no significant difference was detected between partial and total organ excision on patients' OS (p=0.729). For combination therapy, patients who received radiotherapy only (HR=3.21, 95% CI 2.27-4.53) or no surgery and no radiotherapy (HR=2.59, 95% CI 1.83-3.67) were correlated with worse OS (vs. surgery only), but no significant difference was detected between surgery only and surgery combined with radiotherapy on patients' OS (p=0.218). For CSS, the corresponding results were consistent with OS. CONCLUSION: Surgical resection only may be a better survival option for head and neck MEC.

7.
Opt Lett ; 49(12): 3488-3491, 2024 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-38875652

RÉSUMÉ

Low-cost broadband photodetectors (PDs) based on group-IV materials are highly demanded. Herein, a vertical all group-IV graphene-i-n (Gr-i-n) structure based on sputtering-grown undoped Ge0.92Sn0.08/Ge multiple quantum wells (MQWs) on n-Ge substrate was proposed to realize efficient visible/shortwave infrared (VIS/SWIR) dual-band photoresponse. Harnessing Gr-germanium tin (GeSn)/Ge MQWs van der Waals heterojunctions, an extended surface depletion region was established, facilitating separation and transportation of photogenerated carriers at VIS wavelengths. Consequently, remarkable VIS/SWIR dual-band response ranging from 400 to 2000 nm with a rapid response time of 23 µs was achieved. Compared to the PD without Gr, the external quantum efficiency at 420, 660, and 1520 nm was effectively enhanced by 10.2-, 5.2-, and 1.2-fold, reaching 40, 42, and 50%, respectively. This research paves the way for the advancement of all group-IV VIS/SWIR broadband PDs and presents what we believe to be a novel approach to the design of low-cost broadband PDs.

8.
Nano Lett ; 24(25): 7757-7763, 2024 Jun 26.
Article de Anglais | MEDLINE | ID: mdl-38874303

RÉSUMÉ

Terahertz scattering scanning near-field optical microscopy is a robust spectral detection technique with a nanoscale resolution. However, there are still major challenges in investigating the heterogeneity of cell membrane components in individual cells. Here, we present a novel and comprehensive analytical approach for detecting and investigating heterogeneity in cell membrane components at the single-cell level. In comparison to the resolution of the topographical atomic force microscopy image, the spatial resolution of the terahertz near-field amplitude image is 3 times that of the former. This ultrafine resolution enables the compositional distribution in the cell membrane, such as the distribution of extracellular vesicles, to be finely characterized. Furthermore, via extraction of the near-field absorption images at specific frequencies, the visualization and compositional difference analysis of cell membrane components can be presented in detail. These findings have significant implications for the intuitive and visual analysis of cell development and disease evolutionary pathways.


Sujet(s)
Membrane cellulaire , Analyse sur cellule unique , Analyse sur cellule unique/méthodes , Membrane cellulaire/composition chimique , Humains , Imagerie térahertz/méthodes , Microscopie à force atomique/méthodes , Vésicules extracellulaires/composition chimique
9.
Int J Mol Sci ; 25(12)2024 Jun 12.
Article de Anglais | MEDLINE | ID: mdl-38928168

RÉSUMÉ

Drought stress is one of the most severe natural disasters in terms of its frequency, length, impact intensity, and associated losses, making it a significant threat to agricultural productivity. Sorghum (Sorghum bicolor), a C4 plant, shows a wide range of morphological, physiological, and biochemical adaptations in response to drought stress, paving the way for it to endure harsh environments. In arid environments, sorghum exhibits enhanced water uptake and reduced dissipation through its morphological activity, allowing it to withstand drought stress. Sorghum exhibits physiological and biochemical resistance to drought, primarily by adjusting its osmotic potential, scavenging reactive oxygen species, and changing the activities of its antioxidant enzymes. In addition, certain sorghum genes exhibit downregulation capabilities in response to drought stress. Therefore, in the current review, we explore drought tolerance in sorghum, encompassing its morphological characteristics and physiological mechanisms and the identification and selection of its functional genes. The use of modern biotechnological and molecular biological approaches to improving sorghum resistance is critical for selecting and breeding drought-tolerant sorghum varieties.


Sujet(s)
Sécheresses , Régulation de l'expression des gènes végétaux , Espèces réactives de l'oxygène , Sorghum , Facteurs de transcription , Sorghum/génétique , Sorghum/métabolisme , Espèces réactives de l'oxygène/métabolisme , Facteurs de transcription/génétique , Facteurs de transcription/métabolisme , Stress physiologique/génétique , Protéines végétales/génétique , Protéines végétales/métabolisme , Adaptation physiologique/génétique
10.
Cell Chem Biol ; 31(5): 920-931.e6, 2024 May 16.
Article de Anglais | MEDLINE | ID: mdl-38759618

RÉSUMÉ

T cell receptor (TCR) plays a fundamental role in adaptive immunity, and TCR-T cell therapy holds great promise for treating solid tumors and other diseases. However, there is a noticeable absence of chemical tools tuning TCR activity. In our study, we screened natural sterols for their regulatory effects on T cell function and identified 7-alpha-hydroxycholesterol (7a-HC) as a potent inhibitor of TCR signaling. Mechanistically, 7a-HC promoted membrane binding of CD3ε cytoplasmic domain, a crucial signaling component of the TCR-CD3 complex, through alterations in membrane physicochemical properties. Enhanced CD3ε membrane binding impeded the condensation between CD3ε and the key kinase Lck, thereby inhibiting Lck-mediated TCR phosphorylation. Transient treatments of TCR-T cells with 7a-HC resulted in reduced signaling strength, increased memory cell populations, and superior long-term antitumor functions. This study unveils a chemical regulation of TCR signaling, which can be exploited to enhance the long-term efficacy of TCR-T cell therapy.


Sujet(s)
Hydroxycholestérols , Récepteurs aux antigènes des cellules T , Transduction du signal , Transduction du signal/effets des médicaments et des substances chimiques , Récepteurs aux antigènes des cellules T/métabolisme , Récepteurs aux antigènes des cellules T/immunologie , Humains , Hydroxycholestérols/composition chimique , Hydroxycholestérols/métabolisme , Hydroxycholestérols/pharmacologie , Animaux , Souris , Lymphocytes T/effets des médicaments et des substances chimiques , Lymphocytes T/immunologie , Lymphocytes T/métabolisme , Souris de lignée C57BL , Phosphorylation/effets des médicaments et des substances chimiques
11.
Biology (Basel) ; 13(5)2024 May 19.
Article de Anglais | MEDLINE | ID: mdl-38785839

RÉSUMÉ

Cell-to-cell distant mechanical communication has been demonstrated using in vitro and in vivo models. However, the molecular mechanisms underlying long-range cell mechanoresponsive interactions remain to be fully elucidated. This study further examined the roles of α-Catenin and Piezo1 in traction force-induced rapid branch assembly of airway smooth muscle (ASM) cells on a Matrigel hydrogel containing type I collagen. Our findings demonstrated that siRNA-mediated downregulation of α-Catenin or Piezo1 expression or chemical inhibition of Piezo1 activity significantly reduced both directional cell movement and branch assembly. Regarding the role of N-cadherin in regulating branch assembly but not directional migration, our results further confirmed that siRNA-mediated downregulation of α-Catenin expression caused a marked reduction in focal adhesion formation, as assessed by focal Paxillin and Integrin α5 localization. These observations imply that mechanosensitive α-Catenin is involved in both cell-cell and cell-matrix adhesions. Additionally, Piezo1 partially localized in focal adhesions, which was inhibited by siRNA-mediated downregulation of α-Catenin expression. This result provides insights into the Piezo1-mediated mechanosensing of traction force on a hydrogel. Collectively, our findings highlight the significance of α-Catenin in the regulation of cell-matrix interactions and provide a possible interpretation of Piezo1-mediated mechanosensing activity at focal adhesions during cell-cell mechanical communication.

12.
Opt Lett ; 49(9): 2241-2244, 2024 May 01.
Article de Anglais | MEDLINE | ID: mdl-38691689

RÉSUMÉ

Metasurfaces have provided a flexible platform for designing ultracompact metalenses with unusual functionalities. However, traditional multi-foci metalenses are limited to generating circularly polarized (CP) or linearly polarized (LP) focal points, and the intensity distributions are always inhomogeneous/chaotical between the multiple focal points. Here, an inverse design approach is proposed to optimize the in-plane orientation of each meta-atom in a terahertz (THz) multi-foci metalens that can generate multi-polarized focal points with nearly uniform intensity distributions. As a proof-of-principle example, we numerically and experimentally demonstrate an inversely designed metalens for simultaneously generating multiple CP- and LP-based focal points with homogeneous intensity distributions, leading to a multi-polarized image (rather than the holography). Furthermore, the multi-channel and multi-polarized images consisting of multiple focal points with homogeneous intensity distributions are also numerically demonstrated. The unique approach for inversely designing multi-foci metalens that can generate multi-polarized focal points and images with uniform intensity distributions will enable potential applications in imaging and sensing.

13.
Plants (Basel) ; 13(8)2024 Apr 22.
Article de Anglais | MEDLINE | ID: mdl-38674566

RÉSUMÉ

Salinity is one of the major constraints to crop production. Rice is a main staple food and is highly sensitive to salinity. This study aimed to elucidate the effects of salt stress on physiological and agronomic traits of rice genotypes with contrasting salt tolerance. Six contrasting rice genotypes (DJWJ, JFX, NSIC, HKN, XD2H and HHZ), including three salt-tolerant and three salt-sensitive rice genotypes, were grown under two different salt concentrations (0 and 100 mmol L-1 NaCl solution). The results showed that growth, physiological and yield-related traits of both salt-sensitive and salt-tolerant rice were significantly affected by salt stress. In general, plant height, tiller number, dry weight and relative growth rate showed 15.7%, 11.2%, 25.2% and 24.6% more reduction in salt-sensitive rice than in salt-tolerant rice, respectively. On the contrary, antioxidant enzyme activity (superoxide dismutase, peroxidase, catalase), osmotic adjustment substances (proline, soluble protein, malondialdehyde (MDA)) and Na+ content were significantly increased under salt stress, and the increase was far higher in salt-tolerant rice except for MDA. Furthermore, grain yield and yield components significantly decreased under salt stress. Overall, the salt-sensitive rice genotypes showed a 15.3% greater reduction in grain yield, 5.1% reduction in spikelets per panicle, 7.4% reduction in grain-filling percentage and 6.1% reduction in grain weight compared to salt-tolerant genotypes under salt stress. However, a modest gap showed a decline in panicles (22.2% vs. 22.8%) and total spikelets (45.4% vs. 42.1%) between salt-sensitive and salt-tolerant rice under salinity conditions. This study revealed that the yield advantage of salt-tolerant rice was partially caused by more biomass accumulation, growth rate, strong antioxidant capacity and osmotic adjustment ability under salt stress, which contributed to more spikelets per panicle, high grain-filling percentage and grain weight. The results of this study could be helpful in understanding the physiological mechanism of contrasting rice genotypes' responses to salt stress and to the breeding of salt-tolerant rice.

14.
Angew Chem Int Ed Engl ; 63(27): e202406750, 2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38651747

RÉSUMÉ

Electrocatalytic reduction of nitrate to ammonia provides a green alternate to the Haber-Bosch method, yet it suffers from sluggish kinetics and a low yield rate. The nitrate reduction follows a tandem reaction of nitrate reduction to nitrite and subsequent nitrite hydrogenation to generate ammonia, and the ammonia Faraday efficiency (FE) is limited by the competitive hydrogen evolution reaction. Herein, we design a heterostructure catalyst to remedy the above issues, which consists of Ni nanosphere core and Ni(OH)2 nanosheet shell (Ni/Ni(OH)2). In situ Raman spectroscopy reveals Ni and Ni(OH)2 are interconvertible according to the applied potential, facilitating the cascade nitrate reduction synergistically. Consequently, it attains superior electrocatalytic nitrate reduction performance with an ammonia FE of 98.50 % and a current density of 0.934 A cm-2 at -0.476 V versus reversible hydrogen electrode, and exhibits an average ammonia yield rate of 84.74 mg h-1 cm-2 during the 102-hour stability test, which is highly superior to the reported catalysts tested under similar conditions. Density functional theory calculations corroborate the synergistic effect of Ni and Ni(OH)2 in the tandem reaction of nitrate reduction. Moreover, the Ni/Ni(OH)2 catalyst also possesses good capability for methanol oxidation and thus is used to establish a system coupling with nitrate reduction.

15.
Sensors (Basel) ; 24(5)2024 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-38475151

RÉSUMÉ

An equalizer based on a recurrent neural network (RNN), especially with a bidirectional gated recurrent unit (biGRU) structure, is a good choice to deal with nonlinear damage and inter-symbol interference (ISI) in optical communication systems because of its excellent performance in processing time series information. However, its recursive structure prevents the parallelization of the computation, resulting in a low equalization rate. In order to improve the speed without compromising the equalization performance, we propose a minimalist 1D convolutional neural network (CNN) equalizer, which is reconverted from a biGRU with knowledge distillation (KD). In this work, we applied KD to regression problems and explain how KD helps students learn from teachers in solving regression problems. In addition, we compared the biGRU, 1D-CNN after KD and 1D-CNN without KD in terms of Q-factor and equalization velocity. The experimental data showed that the Q-factor of the 1D-CNN increased by 1 dB after KD learning from the biGRU, and KD increased the RoP sensitivity of the 1D-CNN by 0.89 dB with the HD-FEC threshold of 1 × 10-3. At the same time, compared with the biGRU, the proposed 1D-CNN equalizer reduced the computational time consumption by 97% and the number of trainable parameters by 99.3%, with only a 0.5 dB Q-factor penalty. The results demonstrate that the proposed minimalist 1D-CNN equalizer holds significant promise for future practical deployments in optical wireless communication systems.

16.
ACS Omega ; 9(6): 6912-6923, 2024 Feb 13.
Article de Anglais | MEDLINE | ID: mdl-38371850

RÉSUMÉ

To investigate the feasibility and reaction mechanism of combusting sewage sludge and brown coal in a mixture. Thermal behavior evaluation of combustion characteristics, interactions, and kinetic analysis of sludge-lignite mixture combustion by thermogravimetry (TG). The results showed that the combustion performance of the mixed samples was all in between that of the lignite and sludge samples. The combined combustion index gradually decreased with the increase in sludge mixing. The addition of sludge favors the ignition of the mixture but is not conducive to overall stable combustion. The synergies between the sludges, as assessed by the mass loss curves, are reflected in the ash removal and coke oxidation stages. When the mixture of sludge and lignite is burned at a ratio of 10 wt %, the calorific value can still reach 20.3 MJ/kg, which is only about 4.2% lower than that of burning lignite alone. Application of the kinetic models of FWO, Starink, KAS, and Friedman, in turn, determined a minimum average activation energy of only 132.50 kJ/mol. In addition, the reaction was judged to be a simple complexation reaction by analyzing the thermodynamic parameters (ΔG, ΔS, ΔH, and A), with the combustion process approaching thermodynamic equilibrium and forming stable products. The nucleation model A4.2 can be used as the best reaction mechanism model for sludge-lignite mixed combustion.

18.
Nat Commun ; 15(1): 1447, 2024 Feb 16.
Article de Anglais | MEDLINE | ID: mdl-38365760

RÉSUMÉ

Exploring an active and cost-effective electrocatalyst alternative to carbon-supported platinum nanoparticles for alkaline hydrogen evolution reaction (HER) have remained elusive to date. Here, we report a catalyst based on platinum single atoms (SAs) doped into the hetero-interfaced Ru/RuO2 support (referred to as Pt-Ru/RuO2), which features a low HER overpotential, an excellent stability and a distinctly enhanced cost-based activity compared to commercial Pt/C and Ru/C in 1 M KOH. Advanced physico-chemical characterizations disclose that the sluggish water dissociation is accelerated by RuO2 while Pt SAs and the metallic Ru facilitate the subsequent H* combination. Theoretical calculations correlate with the experimental findings. Furthermore, Pt-Ru/RuO2 only requires 1.90 V to reach 1 A cm-2 and delivers a high price activity in the anion exchange membrane water electrolyzer, outperforming the benchmark Pt/C. This research offers a feasible guidance for developing the noble metal-based catalysts with high performance and low cost toward practical H2 production.

19.
Sci Total Environ ; 918: 170628, 2024 Mar 25.
Article de Anglais | MEDLINE | ID: mdl-38325476

RÉSUMÉ

The one-time application of common urea blended with controlled-release urea (CRU) is considered effective for improving nitrogen use efficiency and grain yield and reducing the greenhouse gas emissions of summer maize in intensive agricultural systems. However, the trade-off between the economic and environmental performances of different blended fertilizer treatments for different maize varieties remains unclear. Therefore, a consecutive two-year field experiment was conducted in the North China Plain to study the effects of different ratios of CRU and common urea on the yield, nitrous oxide (N2O) emissions, yield-scaled total N2O emissions, greenhouse gas intensity (GHGI), and net ecosystem economic benefit (NEEB) in 2021 and 2022. Four N fertilizer treatments with equal rate at 180 kg N ha-1 were applied as N180U (all Urea), N180C1(1/3CRU), N180C2(2/3CRU), and N180C (all CRU), and two maize varieties (JNK728-yellow ripe variety and ZD958-green ripe variety) were used. The N180C1 and N180C2 treatments produced the highest grain yield in varieties JNK728 and ZD958 (9.4-11.5 t ha-1 and 9.0-11.0 t ha-1), respectively. Compared to the N180U treatment (conventional method), the N180C1 treatment reduced the GHGI (24.8 %-25.9 %) and increased the NEEB (33.1 %-33.4 %) in the JNK728 variety, whereas the N180C2 treatment reduced the GHGI (16.9 %-28.8 %) and increased the NEEB (27.2 %-48.1 %) in the ZD958 variety. The study concludes that a one-time application of blended nitrogen fertilizer in suitable varieties can minimize the GHGI and maximize the NEEB, which is an effective strategy for balancing yield and nitrogen efficiency in the summer maize system in the North China Plain.


Sujet(s)
Gaz à effet de serre , Gaz à effet de serre/analyse , Sol , Zea mays , Préparations à action retardée , Urée , Engrais/analyse , Écosystème , Méthane/analyse , Agriculture/méthodes , Azote , Grains comestibles/composition chimique , Protoxyde d'azote/analyse , Chine
20.
Mol Genet Genomic Med ; 12(2): e2361, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38348997

RÉSUMÉ

OBJECTIVE: We aimed to evaluate the genotype-phenotype relationship in two Chinese family members with enlarged vestibular aqueduct (EVA). METHODS: We collected blood samples and clinical data from each pedigree family member. Genomic DNA was isolated from peripheral leukocytes using standard methods. Targeted next-generation sequencing and Sanger sequencing were performed to find the pathogenic mutation in this family. Minigene assays were used to verify whether the novel intronic mutation SLC26A4c.765+4A>G influenced mRNA splicing. RESULTS: Hearing loss in the patients with EVA was diagnosed using auditory tests and imaging examinations. Two pathogenic mutations, c.765+4A>G and c.919-2A>G were detected in SLC26A4. In vitro minigene analysis confirmed that c.765+4A>G variant could cause aberrant splicing, resulting in skipping over exon 6. CONCLUSIONS: The SLC26A4c.765+4A>G mutation is the causative variant in the Chinese family with EVA. Particular attention should be paid to intronic variants.


Sujet(s)
Surdité neurosensorielle , Protéines de transport membranaire , Fratrie , Aqueduc du vestibule/malformations , Humains , Protéines de transport membranaire/génétique , Mutation , Chine
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