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1.
Nature ; 631(8019): 98-105, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38867037

ABSTRACT

A key challenge in aerosol pollution studies and climate change assessment is to understand how atmospheric aerosol particles are initially formed1,2. Although new particle formation (NPF) mechanisms have been described at specific sites3-6, in most regions, such mechanisms remain uncertain to a large extent because of the limited ability of atmospheric models to simulate critical NPF processes1,7. Here we synthesize molecular-level experiments to develop comprehensive representations of 11 NPF mechanisms and the complex chemical transformation of precursor gases in a fully coupled global climate model. Combined simulations and observations show that the dominant NPF mechanisms are distinct worldwide and vary with region and altitude. Previously neglected or underrepresented mechanisms involving organics, amines, iodine oxoacids and HNO3 probably dominate NPF in most regions with high concentrations of aerosols or large aerosol radiative forcing; such regions include oceanic and human-polluted continental boundary layers, as well as the upper troposphere over rainforests and Asian monsoon regions. These underrepresented mechanisms also play notable roles in other areas, such as the upper troposphere of the Pacific and Atlantic oceans. Accordingly, NPF accounts for different fractions (10-80%) of the nuclei on which cloud forms at 0.5% supersaturation over various regions in the lower troposphere. The comprehensive simulation of global NPF mechanisms can help improve estimation and source attribution of the climate effects of aerosols.

2.
Sci Total Environ ; 945: 173861, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38871323

ABSTRACT

Coastal wetlands are key players in mitigating global climate change by sequestering soil organic matter. Soil organic matter consists of less stable particulate organic matter (POM) and more stable mineral-associated organic matter (MAOM). The distribution and drivers of MAOM and POM in coastal wetlands have received little attention, despite the processes and mechanisms differ from that in the upland soils. We explored the distribution of POM and MAOM, their contributions to SOM, and the controlling factors along a salinity gradient in an estuarine wetland. In the estuarine wetland, POM C and N were influenced by soil depth and vegetation type, whereas MAOM C and N were influenced only by vegetation type. In the estuarine wetland, SOM was predominantly in the form of MAOM (> 70 %) and increased with salinity (70 %-76 %), leading to long-term C sequestration. Both POM and MAOM increased with SOM, and the increase rate of POM was higher than that of MAOM. Aboveground plant biomass decreased with increasing salinity, resulted in a decrease in POM C (46 %-81 %) and N (52 %-82 %) pools. As the mineral amount and activity, and microbial biomass decreased, the MAOM C (2.5 %-64 %) and N pool (8.6 %-59 %) decreased with salinity. When evaluating POM, the most influential factors were microbial biomass carbon (MBC) and dissolved organic carbon (DOC). Key parameters, including MBC, DOC, soil salinity, soil water content, aboveground plant biomass, mineral content and activity, and bulk density, were identified as influencing factors for both MAOM abundance. Soil water content not only directly controlled MAOM, but together with salinity also indirectly regulated POM and MAOM by controlling microbial biomass and aboveground plant biomass. Our findings have important implications for improving the accumulation and increased stability of soil organic matter in coastal wetlands, considering the global sea level rise and increased frequency of inundation.

3.
Org Lett ; 26(24): 5196-5201, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38858221

ABSTRACT

A novel strategy for incorporating a trifluoroacetyl functionality into a range of structurally varied unsaturated bonds was developed by using PhI(OCOMe)2 as an oxidant with a masked trifluoroacyl reagent as a trifluoroacetyl radical precursor. The oxidative decarboxylation of the masked trifluoroacyl precursor followed by a tandem radical process provides versatile access to 5-exo-trig cyclization of N-arylacrylamides, direct C(sp2)-H trifluoroacetylation of quinolines, isoquinoline, 2H-indazole, and quinoxalin-2(1H)-ones, and C(sp)-H trifluoroacetylation of alkynes. This protocol is characterized by mild reaction conditions, operational simplicity, and broad functional group compatibility.

4.
Anal Chem ; 96(23): 9610-9620, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38822784

ABSTRACT

The emerging field of nanoscale infrared (nano-IR) offers label-free molecular contrast, yet its imaging speed is limited by point-by-point traverse acquisition of a three-dimensional (3D) data cube. Here, we develop a spatial-spectral network (SS-Net), a miniaturized deep-learning model, together with compressive sampling to accelerate the nano-IR imaging. The compressive sampling is performed in both the spatial and spectral domains to accelerate the imaging process. The SS-Net is trained to learn the mapping from small nano-IR image patches to the corresponding spectra. With this elaborated mapping strategy, the training can be finished quickly within several minutes using the subsampled data, eliminating the need for a large-labeled dataset of common deep learning methods. We also designed an efficient loss function, which incorporates the image and spectral similarity to enhance the training. We first validate the SS-Net on an open stimulated Raman-scattering dataset; the results exhibit the potential of 10-fold imaging speed improvement with state-of-the-art performance. We then demonstrate the versatility of this approach on atomic force microscopy infrared (AFM-IR) microscopy with 7-fold imaging speed improvement, even on nanoscale Fourier transform infrared (nano-FTIR) microscopy with up to 261.6 folds faster imaging speed. We further showcase the generalization of this method on AFM-force volume-based multiparametric nanoimaging. This method establishes a paradigm for rapid nano-IR imaging, opening new possibilities for cutting-edge research in materials, photonics, and beyond.

5.
J Hazard Mater ; 476: 134988, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38908178

ABSTRACT

Biochar-derived dissolved organic matter (BDOM), is extensively involved in the recrystallization of minerals and the speciation alteration of associated toxic metals. This study investigates how BDOM extracted from tobacco petiole (TP) or tobacco stalk (TS) biochar influences the speciation repartitioning of Cr(VI) in environments impacted by acid mine drainage (AMD), focusing on interactions with secondary minerals during Schwertmannite (Sch) dissolution and recrystallization. TP-BDOM, rich in lignin-like substances, slowed down the Cr-Sch dissolution and Cr release under acidic conditions compared to TS-BDOM. TP-BDOM's higher O/C component exerts a delayed impact on Cr-Sch stability and Cr(VI) reduction. In-situ ATR-FTIR and 2D-COS analysis showed that carboxylic and aromatic N-OH groups in BDOM could interact with Cr-Sch surfaces, affecting sulfate and Cr(VI) release. It was also observed that slight recrystallization occurred from Cr-Sch to goethite, along with increased Cr incorporation into secondary minerals within TS-BDOM. This enhances our understanding of BDOM's role in Cr(VI) speciation changes in AMD-contaminated sites.

6.
Biochem Pharmacol ; 226: 116345, 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38852643

ABSTRACT

Ferroptosis is a regulated cell death marked by iron-dependent lipid peroxidation. Tumor cells that survive by evading chemotherapy-induced apoptosis are vulnerable to ferroptosis. Therefore, it is particularly urgent to explore active ingredients that can selectively induce ferroptosis in cancer cells. Here, we revealed that sanggenol L, the active agent of Morus Bark, predisposed non-small cell lung cancer (NSCLC) cells to ferroptosis, evidenced by reactive oxygen species (ROS) accumulation, glutathione depletion, mitochondrial shrinkage, and lipid peroxidation. Furthermore, the ferroptosis-related miRNA array showed that sanggenol L treatment upregulated the level of miR-26a-1-3p, which directly targeted the E3 ubiquitin ligase MDM2. In addition, silencing MDM2 by miR-26a-1-3p resulted in a notable increase in p53 protein levels and decrease of its downstream target SLC7A11, ultimately triggered ferroptosis. The subcutaneous xenograft model and patient-derived tumor xenograft (PDX) model of NSCLC further confirmed the anti-tumor efficacy and safety of sanggenol L in vivo. Collectively, our data suggest that miR-26a-1-3p/MDM2/p53/SLC7A11 signaling axis plays a key role in sanggenol L-induced ferroptosis, which implies that sanggenol L can serves as an anticancer therapeutic arsenal for NSCLC.

7.
Adv Mater ; : e2406347, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38926947

ABSTRACT

Electrical generation and transduction of polarized electron spins in semiconductors are of central interest in spintronics and quantum information science. While spin generation in semiconductors has been frequently realized via electrical injection from a ferromagnet, there are significant advantages in nonmagnetic pathways of creating spin polarization. One such pathway exploits the interplay of electron spin with chirality in electronic structures or real space. Here, utilizing chirality-induced spin selectivity (CISS), we demonstrate efficient creation of spin accumulation in n-doped GaAs via electric current injection from a normal metal (Au) electrode through a self-assembled monolayer of chiral molecules (α-helix L-polyalanine, AHPA-L). The resulting spin polarization is detected as a Hanle effect in the n-GaAs, which is found to obey a distinct universal scaling with temperature and bias current consistent with chirality-induced spin accumulation. The experiment constitutes a definitive observation of CISS in a fully nonmagnetic device structure and demonstration of its ability to generate spin accumulation in a conventional semiconductor. The results thus place key constraints on the physical mechanism of CISS and present a new scheme for magnet-free semiconductor spintronics. This article is protected by copyright. All rights reserved.

8.
Heliyon ; 10(11): e32068, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38933972

ABSTRACT

The sports service supply chain faces various potential risks, such as market fluctuations, logistics issues, and partner uncertainties. To address these risks effectively, this study employs a combination of fuzzy comprehensive evaluation (FCE) methods and intelligent neural networks to create an innovative risk management framework. By considering diverse uncertainties and leveraging the analytical power of intelligent neural networks, this study aims to optimize the operation of the sports service supply chain and explore the risk factors within the public service supply chain of stadiums. This framework provides policy references to promote the healthy and sustainable development of the sports service industry. The main empirical findings, based on a representative survey of experts in China, are as follows: (1) When determining the weights of risk indicators for managing the public service supply chain of stadiums using the FCE method, the customer risk indicator is of paramount importance, with a weight of 0.286, accounting for 95.2 % of the total significance; and (2) In evaluating various risk indicators of the public service supply chain of stadiums through the neural network method, the customer risk indicator scores the highest, achieving a score of 76.02. Notably, the customer complaint risk indicator scores slightly higher at 79.33. Based on these findings, the study recommends focusing on enhancing customer experience within risk management strategies. Additionally, it suggests strengthening the supervision of platforms and third-party activities to ensure the stability and efficient operation of the stadium service supply chain. This study aims to provide theoretical support and reference indicators for evaluating the public service capabilities of stadiums.

9.
Environ Pollut ; 355: 124227, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38797348

ABSTRACT

Owing to the significant environmental threat posed by microplastics (MPs) of varying properties, MPs research has garnered considerable attention in current academic discourse. Addressing MPs in river-lake water systems, existing studies have seldom systematically revealed the role of free radicals in the aging/degradation process of MPs. Hence, this review aims to first analyze the pollution distribution and environmental risks of MPs in river-lake water systems and to elaborate the crucial role of free radicals in them. After that, the study delves into the advancements in free radical-mediated degradation techniques for MPs, emphasizing the significance of both the generation and elimination of free radicals. Furthermore, a novel approach is proposed to precisely govern the controlled generation of free radicals for MPs' degradation by interfacial modification of the material structure. Hopefully, it will shed valuable insights for the effective control and reduction of MPs in river-lake water systems.


Subject(s)
Environmental Monitoring , Microplastics , Water Pollutants, Chemical , Water Pollutants, Chemical/chemistry , Free Radicals/chemistry , Environmental Monitoring/methods , Rivers/chemistry , Lakes/chemistry
10.
Shock ; 62(1): 74-84, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38713551

ABSTRACT

ABSTRACT: Ischemia-reperfusion injury (IRI) often stems from an imbalance between mitochondrial dynamics and autophagy. Melatonin mitigates IRI by regulating mitochondrial dynamics. However, the precise molecular mechanism underlying the role of melatonin in reducing IRI through modulating mitochondrial dynamics remains elusive. The objective of this study was to investigate whether pretreatment with melatonin before IRI confers protective effects by modulating mitochondrial dynamics and mitophagy. Melatonin pretreatment was administered to HK-2 cells and live rats before subjecting them to hypoxia-reoxygenation or IRI, respectively. Cells and rat kidney models were evaluated for markers of oxidative stress, autophagy, mitochondrial dynamics, and the expression of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and phospho-AMPKα (P-AMPK). After renal IRI, increased mitochondrial fission and autophagy were observed, accompanied by exacerbated cellular oxidative stress injury and aggravated mitochondrial dysfunction. Nevertheless, melatonin pretreatment inhibited mitochondrial fission, promoted mitochondrial fusion, and attenuated autophagy levels. This intervention was correlated with a notable reduction in oxidative stress injury and remarkable restoration of mitochondrial functionality. Ischemia-reperfusion injury led to a decline in P-AMPK levels, whereas melatonin pretreatment increased the level of P-AMPK levels. Silencing AMPK with small interfering RNA exacerbated mitochondrial damage, and in this context, melatonin pretreatment did not alleviate mitochondrial fission or autophagy levels but resulted in sustained oxidative stress damage. Collectively, these findings indicate that melatonin pretreatment shields the kidneys from IRI by mitigating excessive mitochondrial fission, moderating autophagy levels, and preserving appropriate mitochondrial fission, all in an AMPK-dependent manner.


Subject(s)
AMP-Activated Protein Kinases , Autophagy , Melatonin , Mitochondrial Dynamics , Reperfusion Injury , Melatonin/pharmacology , Melatonin/therapeutic use , Reperfusion Injury/drug therapy , Reperfusion Injury/metabolism , Animals , Mitochondrial Dynamics/drug effects , Autophagy/drug effects , Rats , AMP-Activated Protein Kinases/metabolism , Male , Dynamins/metabolism , Kidney/drug effects , Kidney/pathology , Kidney/metabolism , Kidney/blood supply , Oxidative Stress/drug effects , Humans , Rats, Sprague-Dawley , Cell Line , Mitochondria/drug effects , Mitochondria/metabolism
11.
Clin Chim Acta ; 560: 119718, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38718852

ABSTRACT

Bladder cancer (BC) is ranked as the ninth most common malignancy worldwide, with approximately 570,000 new cases reported annually and over 200,000 deaths. Cystoscopy remains the gold standard for the diagnosis of BC, however, its invasiveness, cost, and discomfort have driven the demand for the development of non-invasive, cost-effective alternatives. Nuclear matrix protein 22 (NMP22) is a promising non-invasive diagnostic tool, having received FDA approval. Traditional methods for detecting NMP22 require a laboratory environment equipped with specialized equipment and trained personnel, thus, the development of NMP22 detection devices holds substantial potential for application. In this review, we evaluate the NMP22 sensors developed over the past decade, including electrochemical, colorimetric, and fluorescence biosensors. These sensors have enhanced detection sensitivity and overcome the limitations of existing diagnostic methods. However, many emerging devices exhibit deficiencies that limit their potential clinical use, therefore, we propose how sensor design can be optimized to enhance the likelihood of clinical translation and discuss the future applications of NMP22 as a legacy biomarker, providing insights for the design of new sensors.


Subject(s)
Nuclear Proteins , Urinary Bladder Neoplasms , Humans , Urinary Bladder Neoplasms/diagnosis , Nuclear Proteins/analysis , Biomarkers, Tumor/analysis , Biosensing Techniques/methods
12.
Sci Total Environ ; 939: 173516, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-38802011

ABSTRACT

Over the past decades, the accumulation of plastics in mangrove ecosystems has emerged as a significant environmental concern, primarily due to anthropogenic activities. Polypropylene (PP) films, one of the plastic types with the highest detection rate, tend to undergo intricate aging processes in mangrove ecosystems, leading to the release of dissolved organic matter (DOM) that may further influence the local bacterial communities. Yet, the specific effects of new and weathered (aged) plastic films and the associated leached DOM on bacterial consortia in mangrove sediments remain poorly understood. In this study, an incubation experiment was conducted to elucidate the immediate effects and mechanisms of the new and relatively short-term (45 or 90 days) aged PP films, as well as their leached DOM (PDOM), on characteristics of DOM and the bacterial community structure in mangrove sediments under different tidal conditions. Surface morphology and functional group analyses showed that both new and aged PP films exhibited comparable degradation profiles under different tidal conditions over the incubation period. As compared to the new PP film treatments, the introduction of the short-term aged PP films significantly affected the content of humic-like compounds in sediments, and such effects were partially ascribed to the release of PDOM during the incubation. Although the addition of PP films and PDOM showed minor effects on the overall diversity and composition of bacterial communities in the sediments, the abundance of some dominant phyla exhibited a growth or reduction tendency, possibly changing their ecological functions. This study was an effective attempt to investigate the relationship among plastic surface characteristics, sedimentary physicochemical properties, and bacterial communities in mangrove sediments. It revealed the ecological ramifications of new and short-term plastic pollution and its leachates in mangrove seedtimes, enhancing our understating of their potential impacts on the health of mangrove ecosystems.


Subject(s)
Bacteria , Geologic Sediments , Polypropylenes , Wetlands , Geologic Sediments/chemistry , Geologic Sediments/microbiology , Water Pollutants, Chemical/analysis , Microbiota
13.
Biochim Biophys Acta Mol Basis Dis ; 1870(6): 167234, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38750769

ABSTRACT

The 5-year survival for non-small cell lung cancer (NSCLC) remains <20 %, primarily due to the early symptoms of lung cancer are inconspicuous. Prompt identification and medical intervention could serve as effective strategies for mitigating the death rate. We therefore set out to identify biomarkers to help diagnose NSCLC. CircRNA microarray and qRT-PCR reveal that sputum circ_0006949 is a potential biomarker for the early diagnosis and therapy of NSCLC, which can enhance the proliferation and clone formation, regulate the cell cycle, and accelerate the migration and invasion of NSCLC cells. Circ_0006949 and miR-4673 are predominantly co-localized in the cytoplasm of NSCLC cell lines and tissues; it upregulates GLUL by adsorption of miR-4673 through competing endogenous RNAs mechanism. The circ_0006949/miR-4673/GLUL axis exerts pro-cancer effects in vitro and in vivo. Circ_0006949 can boost GLUL catalytic activity, and they are highly expressed in NSCLC tissues and correlate with poor prognosis. In summary, circ_0006949 is a potential biomarker for the early diagnosis and therapy of NSCLC. This novel sputum circRNA is statistically more predictive than conventional serum markers for NSCLC diagnosis. Non-invasive detection of patients with early-stage NSCLC using sputum has shown good potential for routine diagnosis and possible screening.


Subject(s)
Biomarkers, Tumor , Carcinoma, Non-Small-Cell Lung , Cell Proliferation , Gene Expression Regulation, Neoplastic , Lung Neoplasms , MicroRNAs , RNA, Circular , Humans , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/diagnosis , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Circular/genetics , RNA, Circular/metabolism , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/diagnosis , Lung Neoplasms/metabolism , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Animals , Cell Line, Tumor , Mice , Male , Female , Cell Movement/genetics , Mice, Nude , Sputum/metabolism
14.
Biochim Biophys Acta Mol Cell Res ; 1871(5): 119744, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38702016

ABSTRACT

BACKGROUND: Lung squamous cell carcinoma (LUSC) is associated with high mortality and has limited therapeutic treatment options. Plasminogen activator urokinase (PLAU) plays important roles in tumor cell malignancy. However, the oncogenic role of PLAU in the progression of LUSC remains unknown. GATA-binding factor 6 (GATA6), a key regulator of lung development, inhibits LUSC cell proliferation and migration, but the underlying regulatory mechanism remains to be further explored. Moreover, the regulatory effect of GATA6 on PLAU expression has not been reported. The aim of this study was to identify the role of PLAU and the transcriptional inhibition mechanism of GATA6 on PLAU expression in LUSC. METHODS: To identify the potential target genes regulated by GATA6, differentially expressed genes (DEGs) obtained from GEO datasets analysis and RNA-seq experiment were subjected to Venn analysis and correlation heatmap analysis. The transcriptional regulatory effects of GATA6 on PLAU expression were detected by real-time PCR, immunoblotting, and dual-luciferase reporter assays. The oncogenic effects of PLAU on LUSC cell proliferation and migration were evaluated by EdU incorporation, Matrigel 3D culture and Transwell assays. PLAU expression was detected in tissue microarray of LUSC via immunohistochemistry (IHC) assay. To determine prognostic factors for prognosis of LUSC patients, the clinicopathological characteristics and PLAU expression were subjected to univariate Cox regression analysis. RESULTS: PLAU overexpression promoted LUSC cell proliferation and migration. PLAU is overexpressed in LUSC tissues compared with normal tissues. Consistently, high PLAU expression, which acts as an independent risk factor, is associated with poor prognosis of LUSC patients. Furthermore, the expression of PLAU is transcriptionally regulated by GATA6. CONCLUSION: In this work, it was revealed that PLAU is a novel oncogene for LUSC and a new molecular regulatory mechanism of GATA6 in LUSC was unveiled. Targeting the GATA6/PLAU pathway might help in the development of novel therapeutic treatment strategies for LUSC.


Subject(s)
Carcinoma, Squamous Cell , Cell Movement , Cell Proliferation , GATA6 Transcription Factor , Gene Expression Regulation, Neoplastic , Lung Neoplasms , GATA6 Transcription Factor/genetics , GATA6 Transcription Factor/metabolism , Humans , Cell Proliferation/genetics , Cell Movement/genetics , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/metabolism , Cell Line, Tumor , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/metabolism , Urokinase-Type Plasminogen Activator/genetics , Urokinase-Type Plasminogen Activator/metabolism , Female , Male , Middle Aged , Membrane Proteins
15.
Article in English | MEDLINE | ID: mdl-38755472

ABSTRACT

The large-scale integration of renewable power poses great challenges to grid stability. Among flexible resources, demand response (DR) stands out for its advantages in cost and efficiency. To identify key factors influencing DR, this study adopted the modified theory of planned behavior (TPB) to establish the conceptual model. Social norms were included as a front-end variable, and institutional factors and electricity consumption habits served as moderating variables. The model was subsequently tested and modified using the structural equation modelling (SEM). Results indicated that social norms can exert a substantial indirect effect on DR behavior. However, due to the deficiency of such norms, the formation of the positive attitude towards DR was hindered, resulting in a low standard coefficient of 0.16. Moreover, the influence of subjective norm on response intention was rejected due to limited perceived external pressure. Perceived behavior control exhibited the most significant direct influence on response intention (0.76). Additionally, the positive effects of situational factors and personal habits on the conversion from response intention to behavior were supported. Based on these findings, several policy suggestions including enhancing publicity and incentive policies were proposed.

16.
Sci Rep ; 14(1): 11322, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38760393

ABSTRACT

Based on the theory of empty hole effect of cutting blasting, the Hopkinson effect and Saint-Venant principle are integrated to establish a two-dimensional calculation model of dynamic stress evolution of the holes wall, and then the dynamic fracture mechanism and damage distribution mode of the rock mass in the cutting area under the action of longitudinal waves are predicted. The results of the calculation and numerical simulation are verified by experiments, and the results show that: The time-varying stress function of the circular cavity wall conforms to the periodic dynamic evolution of the trigonometric function, and the theoretical calculation is consistent with the simulation results. Through the calculation of the round holes cut model and the square empty hole cut model, the change of the shape of the holes in the cut area changes the failure form of the surrounding rock mass. The circular empty hole wall is affected by the stress wave to produce "interval ring" destruction, and the effect of the reflected stretch wave is inhibited. The large range of rock mass in the square empty hole wall produces tensile and shear failure, and the rock mass collapses inward under the influence of the second stage stress. Among them, the empty space utilization rate of the square empty hole model is about 8.5 times that of the circular holes model. Vibration monitoring in the center of the cutting area shows that the vibration effect of the circular empty hole is larger than that of the square empty hole, and the proportion of rock breaking energy is lower.

17.
Sci Adv ; 10(18): eadk8495, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38691598

ABSTRACT

Optically active spin defects in wide bandgap semiconductors serve as a local sensor of multiple degrees of freedom in a variety of "hard" and "soft" condensed matter systems. Taking advantage of the recent progress on quantum sensing using van der Waals (vdW) quantum materials, here we report direct measurements of spin waves excited in magnetic insulator Y3Fe5O12 (YIG) by boron vacancy [Formula: see text] spin defects contained in few-layer-thick hexagonal boron nitride nanoflakes. We show that the ferromagnetic resonance and parametric spin excitations can be effectively detected by [Formula: see text] spin defects under various experimental conditions through optically detected magnetic resonance measurements. The off-resonant dipole interaction between YIG magnons and [Formula: see text] spin defects is mediated by multi-magnon scattering processes, which may find relevant applications in a range of emerging quantum sensing, computing, and metrology technologies. Our results also highlight the opportunities offered by quantum spin defects in layered two-dimensional vdW materials for investigating local spin dynamic behaviors in magnetic solid-state matters.

18.
Article in English | MEDLINE | ID: mdl-38775853

ABSTRACT

As a kind of well-known moxibustion material across the world, Artemisia argyi Folium (AAF) has a definite curative effect. From 1996 to now, various studies on AAF have been increasing year by year. That is why this paper is conducted because of no comprehensive summary except for an essential oil review recently published in 2023. Using "AAF" and "mugwort" as keywords, the related literature was summarized in four internationally recognized databases: PubMed, Web of Science, ACS, and ScienceDirect, mainly include four aspects such as botany, phytochemistry, pharmacology, and clinical application. Four traditional identification methods and two new ones were reported. A total of 136 compounds were identified, among which 23 new terpenoids and two new flavonoids were discovered. The pharmacological effects of AAF mainly focus on anti-inflammatory, anti-tumor, antioxidant, antibacterial, and other aspects. Clinically, it is mainly used in respiratory, immune, digestive, and nervous systems in addition to gynecology. The current research mainly focuses on the composition and pharmacology of AAF. Future studies should thoroughly establish the quality criteria and pharmacokinetics of AAF. According to the different application fields, the corresponding quality standards should be formulated to ensure the efficacy of drugs in the actual treatment.

19.
Environ Pollut ; 351: 124083, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38697244

ABSTRACT

Widespread use of tetracycline (TC) results in its persistent residue and bioaccumulation in aquatic environments, posing a high toxicity to non-target organisms. In this study, a bimetal-doped composite material Ag3PO4/MIL-101(Fe,Cu) has been designed for the treatment of TC in aqueous solutions. As the molar ratio of Fe/Cu in composite is 1:1, the obtained material AP/MFe1Cu1 is placed in an aqueous environment under visible light irradiation in the presence of 3 mM peroxydisulfate (PDS), which forms a photo-Fenton-like catalytic system that can completely degrade TC (10 mg/L) within 60 min. Further, the degradation rate constant (0.0668 min-1) is 5.66 and 7.34 times higher than that of AP/MFe and AP/MCu, respectively, demonstrating a significant advantage over single metal-doped catalysts. DFT calculations confirm the strong adsorption capacity and activation advantage of PDS on the composite surface. Therefore, the continuous photogenerated electrons (e-) accelerate the activation of PDS and the production of SO4•-, resulting in the stripping of abundant photogenerated h + for TC oxidation. Meanwhile, the internal circulation of FeⅢ/FeⅡ and CuⅡ/CuⅢ in composite also greatly enhances the photo-Fenton-like catalytic stability. According to the competitive dynamic experiments, SO4•- have the greatest contribution to TC degradation (58.93%), followed by 1O2 (23.80%). The degradation intermediates (products) identified by high-performance liquid chromatography-mass spectrometry (HPLC/MS) technique indicate the involvement of various processes in TC degradation, such as dehydroxylation, deamination, N-demethylation, and ring opening. Furthermore, as the reaction proceeds, the toxicity of the intermediates produced during TC degradation gradually decreases, which can ensure the safety of the aquatic ecosystem. Overall, this work reveals the synergy mechanism of PDS catalysis and photocatalysis, as well as provides technical support for removal of TC-contaminated wastewater.


Subject(s)
Copper , Iron , Metal-Organic Frameworks , Water Pollutants, Chemical , Catalysis , Copper/chemistry , Iron/chemistry , Metal-Organic Frameworks/chemistry , Water Pollutants, Chemical/chemistry , Silver Compounds/chemistry , Density Functional Theory , Electrons , Hydrogen Peroxide/chemistry , Phosphates
20.
Plant Biotechnol J ; 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38600703

ABSTRACT

Sterols have long been associated with diverse fields, such as cancer treatment, drug development, and plant growth; however, their underlying mechanisms and functions remain enigmatic. Here, we unveil a critical role played by a GmNF-YC9-mediated CCAAT-box transcription complex in modulating the steroid metabolism pathway within soybeans. Specifically, this complex directly activates squalene monooxygenase (GmSQE1), which is a rate-limiting enzyme in steroid synthesis. Our findings demonstrate that overexpression of either GmNF-YC9 or GmSQE1 significantly enhances soybean stress tolerance, while the inhibition of SQE weakens this tolerance. Field experiments conducted over two seasons further reveal increased yields per plant in both GmNF-YC9 and GmSQE1 overexpressing plants under drought stress conditions. This enhanced stress tolerance is attributed to the reduction of abiotic stress-induced cell oxidative damage. Transcriptome and metabolome analyses shed light on the upregulation of multiple sterol compounds, including fucosterol and soyasaponin II, in GmNF-YC9 and GmSQE1 overexpressing soybean plants under stress conditions. Intriguingly, the application of soybean steroids, including fucosterol and soyasaponin II, significantly improves drought tolerance in soybean, wheat, foxtail millet, and maize. These findings underscore the pivotal role of soybean steroids in countering oxidative stress in plants and offer a new research strategy for enhancing crop stress tolerance and quality from gene regulation to chemical intervention.

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