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1.
Nano Lett ; 24(18): 5444-5452, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38639448

RESUMO

We report, for the first time, a new synthetic strategy for the preparation of crystalline two-dimensional olefin-linked covalent organic frameworks (COFs) based on aldol condensation between benzodifurandione and aromatic aldehydes. Olefin-linked COFs can be facilely crystallized through either a pyridine-promoted solvothermal process or a benzoic anhydride-mediated organic flux synthesis. The resultant COF leaf with high in-plane π-conjugation exhibits efficient visible-light-driven photoreduction of carbon dioxide (CO2) with water (H2O) in the absence of any photosensitizer, sacrificial agents, or cocatalysts. The production rate of carbon monoxide (CO) reaches as high as 158.1 µmol g-1 h-1 with near 100% CO selectivity, which is accompanied by the oxidation of H2O to oxygen. Both theoretical and experimental results confirm that the key lies in achieving exceptional photoinduced charge separation and low exciton binding. We anticipate that our findings will facilitate new possibilities for the development of semiconducting COFs with structural diversity and functional variability.

2.
Small ; : e2406165, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39126365

RESUMO

The calcium looping technology employing CaO-based sorbents is pivotal for capturing CO2 from flue gas. However, the intrinsic low thermodynamic stability of CaO-based sorbents and the requisite molding step induce severe sintering issues, diminishing their cyclic stability. Herein, a high-entropy fluorite oxide (HEFO) inert stabilizer premised on entropy stabilization and synergistic effect strategies is introduced. HEFO-modified, CaO-based sorbent pellets are synthesized via a rapid cigarette butt-assisted combustion process (15 min) combined with the graphite molding method. Post-multiple cycles, their CO2 capture capacity reaches 0.373 g g-1, which is 2.6-fold superior to that of pure CaO, demonstrating markedly enhanced anti-sintering properties. First, the subtle morphological and crystallographic modifications suggest that the inherent entropy stability of HEFO imparts robust thermal resistance. Concurrently, the disordered structure of single-phase HEFO exhibits a high affinity for CaO, resulting in an interface binding energy of -1.83 eV, in sharp contrast to the -0.112 eV of pure CaO, thereby restricting CaO migration. Additionally, the multi-element synergistic effect of HEFO reduces the energy barrier by 0.15 eV, leading to a 40% and 140% increase in carbonation and calcination rates, respectively. This work presents highly efficient and rapidly synthesized CaO-based sorbent pellets, showcasing promising potential for industrial application.

3.
Exp Brain Res ; 242(10): 2391-2404, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39136723

RESUMO

This study aimed to utilize the nonnegative matrix factorization (NNMF) algorithm for muscle synergy analysis, extracting synergy structures and muscle weightings and mining biomarkers reflecting changes in muscle fatigue from these synergy structures. A leg press exercise to induce fatigue was performed by 11 participants. Surface electromyography (sEMG) data from seven muscles, electrocardiography (ECG) data, Borg CR-10 scale scores, and the z-axis acceleration of the weight block were simultaneously collected. Three indices were derived from the synergy structures: activation phase difference, coactivation area, and coactivation time. The indicators were further validated for single-leg landing. Differences in heart rate (HR) and heart rate variability (HRV) were observed across different fatigue levels, with varying degrees of disparity. The median frequency (MDF) exhibited a consistent decline in the primary working muscle groups. Significant differences were noted in activation phase difference, coactivation area, and coactivation time before and after fatigue onset. Moreover, a significant correlation was found between the activation phase difference and the coactivation area with fatigue intensity. The further application of single-leg landing demonstrated the effectiveness of the coactivation area. These indices can serve as biomarkers reflecting simultaneous alterations in the central nervous system and muscle activity post-exertion.


Assuntos
Eletromiografia , Frequência Cardíaca , Fadiga Muscular , Músculo Esquelético , Humanos , Masculino , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto Jovem , Adulto , Frequência Cardíaca/fisiologia , Eletrocardiografia , Feminino , Algoritmos
4.
Environ Sci Technol ; 58(18): 7691-7709, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38664958

RESUMO

More and more attention has been paid to condensable particulate matter (CPM) since its emissions have surpassed that of filterable particulate matter (FPM) with the large-scale application of ultralow-emission reform. CPM is a gaseous material in the flue stack but instantly turns into particles after leaving the stack. It is composed of inorganic and organic components. Organic components are an important part of CPM, and they are an irritant, teratogenic, and carcinogenic, which triggers photochemical smog, urban haze, and acid deposition. CPM organic components can aggravate air pollution and climate change; therefore, consideration should be given to them. Based on existing methods for removing atmospheric organic pollutants and combined with the characteristics of CPM organic components, we provide a critical overview from the aspects of (i) fundamental cognition of CPM, (ii) common methods to control CPM organic components, and (iii) catalytic oxidation of CPM organic components. As one of the most encouraging methods, catalytic oxidation is discussed in detail, especially in combination with selective catalytic reduction (SCR) technology, to meet the growing demands for multipollutant control (MPC). We believe that this review is inspiring for a fuller understanding and deeper exploration of promising approaches to control CPM organic components.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluição do Ar/prevenção & controle
5.
Langenbecks Arch Surg ; 409(1): 81, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430305

RESUMO

PURPOSE: This study aims to compare the efficiency and clinical outcomes between the suctioning ureteral access sheath (UAS) group and the traditional UAS group during retrograde intrarenal surgery (RIRS) for kidney stones and explore the impact of suctioning UAS on postoperative infectious complications. METHODS: We retrospectively reviewed the clinical data of 162 patients with kidney stones who underwent RIRS with a traditional UAS (n = 74) or a suctioning UAS (n = 71) between March 2021 and May 2023. RESULTS: The mean operative time in suctioning UAS group (39.03 ± 18.01 s) was significantly shorter than that (49.73 ± 20.77 s) in the traditional UAS group (P = 0.037). The mean postoperative hospital stay was significantly shorter in the suctioning UAS group (1.57 ± 0.82d) compared with the traditional UAS group (2.30 ± 1.6 2 d) (P = 0.032). The instant SFRs were significantly higher in the suctioning UAS group (88.73%) than in the traditional UAS group (75.68%) (P = 0.040). The overall SFR in suctioning UAS group (92.96%) was slightly higher than the traditional UAS group (85.14%). The incidence of overall complications was significantly higher in the traditional UAS group (35.14%) than in the suctioning UAS group (16.90%) (P = 0.013). In multivariate analysis, female patients (OR 0.053, P = 0.018), positive urine WBC (OR 10.382, P = 0.034), operative time > 60 min (OR 20.231, P = 0.032), and the application of traditional UAS (OR 0.042, P = 0.017) were independent risk factors associated with infectious complications. CONCLUSION: We demonstrated that suctioning UAS provided a higher instant SFR and fewer postoperative infectious complications during RIRS, and patients with predictable risk factors for infectious complications could potentially benefit from the use of the suctioning UAS.


Assuntos
Cálculos Renais , Ureter , Humanos , Feminino , Estudos Retrospectivos , Cálculos Renais/cirurgia , Tempo de Internação , Análise Multivariada , Complicações Pós-Operatórias/epidemiologia
6.
MAGMA ; 37(3): 397-409, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38386151

RESUMO

Subject motion is a long-standing problem of magnetic resonance imaging (MRI), which can seriously deteriorate the image quality. Various prospective and retrospective methods have been proposed for MRI motion correction, among which deep learning approaches have achieved state-of-the-art motion correction performance. This survey paper aims to provide a comprehensive review of deep learning-based MRI motion correction methods. Neural networks used for motion artifacts reduction and motion estimation in the image domain or frequency domain are detailed. Furthermore, besides motion-corrected MRI reconstruction, how estimated motion is applied in other downstream tasks is briefly introduced, aiming to strengthen the interaction between different research areas. Finally, we identify current limitations and point out future directions of deep learning-based MRI motion correction.


Assuntos
Algoritmos , Artefatos , Inteligência Artificial , Aprendizado Profundo , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Movimento (Física) , Redes Neurais de Computação , Humanos , Imageamento por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Movimento
7.
Ren Fail ; 46(2): 2390566, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39230050

RESUMO

OBJECTIVE: To investigate the association between atherogenic index of plasma (AIP) and kidney stones (KS) occurrence and recurrence. METHODS: Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 2007-2014. Non-pregnant adults who provided complete information on AIP and KS were included in the analyses. AIP was calculated as log (triglyceride/high-density lipoprotein cholesterol). KS was ascertained with questionnaires. Weighted multivariable logistic regression model and restricted cubic spline (RCS) were applied to examine the associations between AIP and KS occurrence and recurrence. RESULTS: A total of 6488 subjects (weighted mean age 43.19 years and 49.26% male) with a weighted mean AIP of 0.66 were included in this study. The multivariable-adjusted OR for nephrolithiasis occurrence across consecutive tertiles was 1.00 (reference), 1.21 (95% CI: 0.90-1.62), and 1.85 (95% CI: 1.39-2.48), respectively. Moreover, each SD increment of AIP was associated with a 50% (OR:1.50, 95% CI: 1.25-1.81) higher risk of nephrolithiasis recurrence. RCSs showed significant and linear dose-response relationships between AIP and nephrolithiasis occurrence (p-overall = 0.006, p-nonlinear = 0.689) and recurrence (p-overall = 0.001, p-nonlinear = 0.848). The positive associations between AIP and nephrolithiasis occurrence and recurrence persisted in sensitivity analyses, suggesting the robustness of the results. CONCLUSION: In the current US nationally representative cross-sectional study, AIP was positively associated with KS occurrence and recurrence.


Assuntos
Aterosclerose , Cálculos Renais , Inquéritos Nutricionais , Humanos , Masculino , Feminino , Estudos Transversais , Adulto , Cálculos Renais/epidemiologia , Cálculos Renais/sangue , Pessoa de Meia-Idade , Prevalência , Aterosclerose/epidemiologia , Aterosclerose/sangue , Aterosclerose/etiologia , Triglicerídeos/sangue , Fatores de Risco , Recidiva , HDL-Colesterol/sangue , Estados Unidos/epidemiologia , Modelos Logísticos
8.
Int J Mol Sci ; 25(2)2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38255831

RESUMO

Changes in the atmospheric CO2 concentration influence plant growth and development by affecting the morphological structure and photosynthetic performance. Despite evidence for the macro-effects of elevated CO2 concentrations on plant morphology and yield in tomato, the gene regulatory network and key genes related to cross-regulation have not been reported. To identify the hub genes and metabolic pathways involved in the response of tomato to CO2 enrichment, weighted gene co-expression network analysis was conducted using gene expression profiles obtained by RNA sequencing. The role of the photosynthesis-related gene Soly720 (Solyc01g007720) in CO2-enriched tomato plants was explored. Tomato plants responded to CO2 enrichment primarily through RNA-related pathways and the metabolism of amino acids, fatty acids, and carbohydrates. The hub genes in co-expression networks were associated with plant growth and development, including cellular components and photosynthesis. Compared to wild-type plants, transgenic plants overexpressing the Soly720 gene exhibited 13.4%, 5.5%, 8.9%, and 4.1% increases in plant height, stem diameter, leaf length, and leaf width, respectively, under high-CO2 conditions. The morphological improvements in transgenic plants were accompanied by enhancement of photosynthetic performance in terms of chlorophyll contents, photosynthetic characteristics, and key enzyme activities. This study elucidates the response network of tomato to CO2 enrichment and demonstrates the regulatory role of Soly720 in photosynthesis under high-CO2 conditions.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Dióxido de Carbono , Fotossíntese/genética , Clorofila , Plantas Geneticamente Modificadas/genética
9.
Angew Chem Int Ed Engl ; : e202411508, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014940

RESUMO

The conversion of CO2 to C2 through photocatalysis poses significant challenges, and one of the biggest hurdles stems from the sluggishness of the multi-electron transfer process. Herein, taking metal-organic framework (PFC-98) as a model photocatalyst, we report a new strategy to facilitate charge separation. This strategy involves matching the energy levels of the lowest unoccupied node and linker orbitals of the MOF, thereby creating the lowest unoccupied crystal orbital (LUCO) delocalized over both the node and linker. This feature enables the direct excitation of electrons from photosensitive linker to the catalytic centers, achieving a direct charge transfer (DCT) pathway. For comparison, an isoreticular MOF (PFC-6) based on analogue components but with far apart frontier energy level was synthesized. The delocalized LUCO caused the presence of an internal charge-separated state (ICS), prolonging the excited state lifetime and further inhibiting the electron-hole recombination. The presence of an internal charge-separated state (ICS) prolongs the excited state lifetime and further inhibits the electron-hole recombination. Moreover, it also induced abundant electrons accumulating at the catalytic sites, enabling the multi-electron transfer process. As a result, the material featuring delocalized LUCO exhibits superior overall CO2 photocatalytic performance with high C2 production yield and selectivity.

10.
J Am Chem Soc ; 145(35): 19312-19320, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37611205

RESUMO

The establishment of active sites as the frustrated Lewis pair (FLP) has recently attracted much attention ranging from homogeneous to heterogeneous systems in the field of catalysis. Their unquenched reactivity of Lewis acid and base pairs in close proximity that are unable to form stable adducts has been shown to activate small molecules such as dihydrogen heterolytically. Herein, we show that grafted Ru metal-organic framework-based catalysts prepared via N-containing linkers are rather catalytically inactive for H2 activation despite the application of elevated temperatures. However, upon light illumination, charge polarization of the anchored Ru bipyridine complex can form a transient Lewis acid-base pair, Ru+-N- via metal-to-ligand charge transfer, as confirmed by time-dependent density functional theory (TDDFT) calculations to carry out effective H2-D2 exchange. FTIR and 2-D NMR endorse the formation of such reactive intermediate(s) upon light irradiation.

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