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1.
Sci Total Environ ; 954: 176363, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39299309

RESUMO

Large trees are essential for carbon storage and biodiversity conservation. While an increasing number of studies have focused on large trees in primary forests, little is known about them in secondary and planted forests. We surveyed 86,936 trees in secondary forests and 91,294 trees in planted forests in Zhejiang, China, to investigate the distribution patterns and determinants of large trees in these forests. We found a mean density of large trees (DBH ≥ 30 cm) of 15 ± 13 stems ha-1 in secondary forests and 11 ± 9 stems ha-1 in planted forests. Moreover, the mean density of trees with DBH ≥ 60 cm was 0.36 stems ha-1, indicating that large trees are particularly rare in secondary and planted forests. These large trees were primarily occurred in secondary forests that living in high-elevation area with less human exploitation and colder and wetter climates, and in planted forests with higher species richness and lower tree density. In addition, the density of large trees in these forests significantly increased with tree species richness and decreased with increasing tree density. These results indicate that the sparse large trees were the legacy of historical human activities in the studied area, but currently, the development of large trees is still limited by the improper forest structure characterized by low species diversity and high tree density. To better conserve large trees, there is an urgent need for enhanced conservation policies for secondary forests, such as establishing forest parks for forests with large trees, and implementing near-natural forest management practices for planted forests, which include planting mixed native tree species and maintaining moderate tree density.

2.
Vet Microbiol ; 297: 110199, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39096789

RESUMO

Japanese encephalitis virus (JEV) is a mosquito-borne, zoonotic orthoflavivirus causing human encephalitis and reproductive disorders in pigs. Cell-intrinsic antiviral restriction factors are the first line of defense that prevent a virus from establishing a productive infection, while the molecular mechanism of the virus-host interaction is still not fully understood. Our in vitro experiments demonstrated that the Solute Carrier Family 25 Member 12 (SLC25A12) interacted with the JEV nonstructural protein 1 (NS1) and inhibited JEV replication. Furthermore, we showed that knockdown or knockout of SLC25A12 promoted JEV replication, while overexpression of SLC25A12 repressed viral replication. Finally, we demonstrated that SLC25A12 increased IRF7 mRNA levels, which promoted IFN-ß expression and subsequently induced antiviral effects. Collectively, our study revealed that SLC25A12 interacted with NS1, inhibiting viral RNA synthesis and transcription and enhancing type I interferon induction for antiviral effects.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Interferon Tipo I , Proteínas não Estruturais Virais , Replicação Viral , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Vírus da Encefalite Japonesa (Espécie)/imunologia , Vírus da Encefalite Japonesa (Espécie)/genética , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Interferon Tipo I/metabolismo , Interferon Tipo I/imunologia , Interferon Tipo I/genética , Animais , Humanos , Suínos , Linhagem Celular , Células HEK293 , Encefalite Japonesa/virologia , Encefalite Japonesa/imunologia , Interferon beta/genética , Interferon beta/metabolismo , Interferon beta/imunologia , Interações Hospedeiro-Patógeno
3.
Angew Chem Int Ed Engl ; : e202408736, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107260

RESUMO

The electrooxidation of catalyst surfaces is across various electrocatalytic reactions, directly impacting their activity, stability and selectivity. Precisely characterizing the electrooxidation on well-defined surfaces is essential to understanding electrocatalytic reactions comprehensively. Herein, we employed in situ Raman spectroscopy to monitor the electrooxidation process of palladium single crystal. Our findings reveal that the Pd surface's initial electrooxidation process involves forming *OH intermediate and ClO4 - ions facilitate the deprotonation process, leading to the formation of PdOx. Subsequently, under deep electrooxidation potential range, the oxygen atoms within PdOx contribute to creating surface-bound peroxide species, ultimately resulting in oxygen generation. The adsorption strength of *OH and the coverage of ClO4 - can be adjusted by the controllable electronic effect, resulting in different oxidation rates. This study offers valuable insights into elucidating the electrooxidation mechanisms underlying a range of electrocatalytic reactions, thereby contributing to the rational design of catalysts.

4.
Langmuir ; 40(33): 17454-17462, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39101658

RESUMO

In nature, selective interactions between chiral amino acids and crystals are important for the formation of chiral biominerals and provide insight into the mysterious origin of homochirality. Here, we show that chiral amino acids with different hydrophilicities/hydrophobicities exhibit different chiral selectivity preferences in the dynamically growing gypsum [001] steps. Hydrophilic amino acids show a chiral selectivity preference for their d-isomers, whereas hydrophobic amino acids prefer their l-isomers. These differences in chiral recognition can be attributed to the different stereochemical matching between the hydrophilic and hydrophobic amino acids on the [001] steps of growing gypsum. These different chiral selectivities resulting from the amino acid hydrophilicity/hydrophobicity are confirmed by the experimental crystallization investigations from nano regulation on dynamic steps, to microscopic modification of gypsum morphology, and to macroscopic precipitation. Furthermore, as the hydrophilicity of amino acids increases, the disparity in chiral selection rises; conversely, the increase in the hydrophobicity of amino acids results in a decline in chiral selection. These insights improve our understanding of the interaction mechanism between amino acids and crystals and provide insights into the formation process of chiral biominerals and the origin of homochirality in nature.


Assuntos
Aminoácidos , Sulfato de Cálcio , Cristalização , Interações Hidrofóbicas e Hidrofílicas , Sulfato de Cálcio/química , Aminoácidos/química , Estereoisomerismo , Propriedades de Superfície
5.
Nat Commun ; 15(1): 5792, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987247

RESUMO

The construction of a large-scale quantum internet requires quantum repeaters containing multiple entangled photon sources with identical wavelengths. Semiconductor quantum dots can generate entangled photon pairs deterministically with high fidelity. However, realizing wavelength-matched quantum-dot entangled photon sources faces two difficulties: the non-uniformity of emission wavelength and exciton fine-structure splitting induced fidelity reduction. Typically, these two factors are not independently tunable, making it challenging to achieve simultaneous improvement. In this work, we demonstrate wavelength-tunable entangled photon sources based on droplet-etched GaAs quantum dots through the combined use of AC and quantum-confined Stark effects. The emission wavelength can be tuned by ~1 meV while preserving an entanglement fidelity f exceeding 0.955(1) in the entire tuning range. Based on this hybrid tuning scheme, we finally demonstrate multiple wavelength-matched entangled photon sources with f > 0.919(3), paving the way towards robust and scalable on-demand entangled photon sources for quantum internet and integrated quantum optical circuits.

6.
Nat Commun ; 15(1): 6342, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068194

RESUMO

Existing studies indicate that future global carbon dioxide (CO2) removal (CDR) efforts could largely be concentrated in Asia. However, there is limited understanding of how individual Asian countries and regions will respond to varying and uncertain scales of future CDR concerning their energy-land-water system. We address this gap by modeling various levels of CDR-reliant pathways under climate change ambitions in Asia. We find that high CDR reliance leads to residual fossil fuel and industry emissions of about 8 Gigatonnes CO2yr-1 (GtCO2yr-1) by 2050, compared to less than 1 GtCO2yr-1 under moderate-to-low CDR reliance. Moreover, expectations of multi-gigatonne CDR could delay the achievement of domestic net zero CO2 emissions for several Asian countries and regions, and lead to higher land allocation and fertilizer demand for bioenergy crop cultivation. Here, we show that Asian countries and regions should prioritize emission reduction strategies while capitalizing on the advantages of carbon removal when it is most viable.

8.
Medicine (Baltimore) ; 103(25): e38617, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38905422

RESUMO

BACKGROUND: Vertebral artery stump syndrome (VASS) is a cause of acute stroke. Owing to the particularity of the pathogenesis of VASS, interventional treatment of VASS is difficult. Common mechanical thrombectomy approaches include femoral and radial artery approaches. However, conventional approaches may not be suitable for VASS. If effective measures are not taken to open offending vessels in time, this can lead to a high rate of disability. In recent years, no consensus has been reached regarding surgical methods for treating VASS. PATIENT CONCERNS: The patient presented to the emergency department with a 2-hour history of disturbance of consciousness. DIAGNOSIS: After neurological and magnetic resonance imaging examinations, the patient was diagnosed with acute large vessel occlusive posterior circulation cerebral infarction. METHODS: The patient's symptoms were not relieved after intravenous infusion of argatroban (10 mg) at a local hospital. We first attempted to open the occluded vertebral artery through normal approaches but failed. We then punctured the vertebral artery, successfully opened the occluded vertebral artery, and performed mechanical thrombectomy. RESULTS: The patient underwent successful vertebral artery puncture and mechanical thrombectomy, with no evidence of postoperative bleeding or vascular injury at the puncture site. The patient regained consciousness the day after surgery but remained impaired in physical activity. After 4 months of rehabilitation, the patient recovered completely. CONCLUSION: When the conventional approach cannot meet the requirements of mechanical thrombectomy, reverse puncture of the vertebral artery is a feasible surgical method for patients with VASS. However, due to the small number of cases, a series of safety problems such as potential puncture failure, hemorrhage after puncture, and vascular occlusion still need to be further explored.


Assuntos
Artéria Vertebral , Insuficiência Vertebrobasilar , Humanos , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/cirurgia , Insuficiência Vertebrobasilar/cirurgia , Masculino , Punções/métodos , Artéria Basilar/cirurgia , Artéria Basilar/diagnóstico por imagem , Trombectomia/métodos , Pessoa de Meia-Idade , Arteriopatias Oclusivas/cirurgia , Idoso
9.
Phys Chem Chem Phys ; 26(23): 16891-16897, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38833218

RESUMO

The interfaces between heavy metals and antiferromagnetic materials have garnered significant attention due to their interesting physical properties. La0.35Sr0.65MnO3 (LSMO), as a typical manganite, exhibits an antiferromagnetic ground state that can be controlled through epitaxial strain and interfacial spin-orbit coupling. In this work, we reported the diverse magnetoresistance, influenced by the interfacial magnetic state, in Pt (3 nm)/LSMO (6-20 nm) heterostructures. The strong spin-orbit coupling of Pt and Dzyaloshinskii-Moriya interaction alter the spin structure and enhance the electron scattering at the Pt/LSMO interface, resulting in positive magnetoresistance. The interfacial angular-dependent magnetoresistance modulated by the interfacial magnetic states was also observed in the Pt/LSMO (20 nm) heterostructures. Our findings contribute to a broader understanding of interfacial properties between heavy metals and antiferromagnetic manganites.

10.
Chin Med J (Engl) ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38879805

RESUMO

BACKGROUND: G protein-coupled receptor kinase 2 (GRK2) could participate in the regulation of diverse cells via interacting with non-G-protein-coupled receptors. In the present work, we explored how paroxetine, a GRK2 inhibitor, modulates the differentiation and activation of immune cells in rheumatoid arthritis (RA). METHODS: The blood samples of healthy individuals and RA patients were collected between July 2021 and March 2022 from the First Affiliated Hospital of Anhui Medical University. C57BL/6 mice were used to induce the collagen-induced arthritis (CIA) model. Flow cytometry analysis was used to characterize the differentiation and function of dendritic cells (DCs)/T cells. Co-immunoprecipitation was used to explore the specific molecular mechanism. RESULTS: In patients with RA, high expression of GRK2 in peripheral blood lymphocytes, accompanied by the increases of phosphatidylinositol 3 kinase (PI3K), protein kinase B (AKT), and mammalian target of rapamycin (mTOR). In animal model, a decrease in regulatory T cells (Tregs), an increase in the cluster of differentiation 8 positive (CD8+) T cells, and maturation of DCs were observed. Paroxetine, when used in vitro and in CIA mice, restrained the maturation of DCs and the differentiation of CD8+ T cells, and induced the proportion of Tregs. Paroxetine inhibited the secretion of pro-inflammatory cytokines, the expression of C-C motif chemokine receptor 7 in DCs and T cells. Simultaneously, paroxetine upregulated the expression of programmed death ligand 1, and anti-inflammatory cytokines. Additionally, paroxetine inhibited the PI3K-AKT-mTOR metabolic pathway in both DCs and T cells. This was associated with a reduction in mitochondrial membrane potential and changes in the utilization of glucose and lipids, particularly in DCs. Paroxetine reversed PI3K-AKT pathway activation induced by 740 Y-P (a PI3K agonist) through inhibiting the interaction between GRK2 and PI3K in DCs and T cells. CONCLUSION: Paroxetine exerts an immunosuppressive effect by targeting GRK2, which subsequently inhibits the metabolism-related PI3K-AKT-mTOR pathway of DCs and T cell in RA.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38875092

RESUMO

Deep neural networks (DNNs) have been widely used in many artificial intelligence (AI) tasks. However, deploying them brings significant challenges due to the huge cost of memory, energy, and computation. To address these challenges, researchers have developed various model compression techniques such as model quantization and model pruning. Recently, there has been a surge in research on compression methods to achieve model efficiency while retaining performance. Furthermore, more and more works focus on customizing the DNN hardware accelerators to better leverage the model compression techniques. In addition to efficiency, preserving security and privacy is critical for deploying DNNs. However, the vast and diverse body of related works can be overwhelming. This inspires us to conduct a comprehensive survey on recent research toward the goal of high-performance, cost-efficient, and safe deployment of DNNs. Our survey first covers the mainstream model compression techniques, such as model quantization, model pruning, knowledge distillation, and optimizations of nonlinear operations. We then introduce recent advances in designing hardware accelerators that can adapt to efficient model compression approaches. In addition, we discuss how homomorphic encryption can be integrated to secure DNN deployment. Finally, we discuss several issues, such as hardware evaluation, generalization, and integration of various compression approaches. Overall, we aim to provide a big picture of efficient DNNs from algorithm to hardware accelerators and security perspectives.

12.
Molecules ; 29(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38930897

RESUMO

This study investigated the mechanism by which fucoxanthin acts as a novel ferroptosis inducer to inhibit tongue cancer. The MTT assay was used to detect the inhibitory effects of fucoxanthin on SCC-25 human tongue squamous carcinoma cells. The levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), and total iron were measured. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blotting were used to assess glutathione peroxidase 4 (GPX4), nuclear factor erythroid 2-related factor 2 (Nrf2), Keap1, solute carrier family 7 member 11 (SLC7A11), transferrin receptor protein 1 (TFR1), p53, and heme oxygenase 1 (HO-1) expression. Molecular docking was performed to validate interactions. Compared with the control group, the activity of fucoxanthin-treated SCC-25 cells significantly decreased in a dose- and time-dependent manner. The levels of MMP, GSH, and SOD significantly decreased in fucoxanthin-treated SCC-25 cells; the levels of ROS, MDA, and total iron significantly increased. mRNA and protein expression levels of Keap1, GPX4, Nrf2, and HO-1 in fucoxanthin-treated cells were significantly decreased, whereas levels of TFR1 and p53 were significantly increased, in a concentration-dependent manner. Molecular docking analysis revealed that binding free energies of fucoxanthin with p53, SLC7A11, GPX4, Nrf2, Keap1, HO-1, and TFR1 were below -5 kcal/mol, primarily based on active site hydrogen bonding. Our findings suggest that fucoxanthin can induce ferroptosis in SCC-25 cells, highlighting its potential as a treatment for tongue cancer.


Assuntos
Ferroptose , Heme Oxigenase-1 , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2 , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Xantofilas , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Ferroptose/efeitos dos fármacos , Xantofilas/farmacologia , Xantofilas/química , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/genética , Linhagem Celular Tumoral , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Língua/tratamento farmacológico , Neoplasias da Língua/metabolismo , Neoplasias da Língua/patologia , Receptores da Transferrina/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sistema y+ de Transporte de Aminoácidos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Superóxido Dismutase/metabolismo , Regulação para Baixo/efeitos dos fármacos , Antígenos CD
13.
Huan Jing Ke Xue ; 45(6): 3329-3340, 2024 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-38897755

RESUMO

With rapid urbanization and human activities exacerbating threats to the degradation of various ecosystem services in modern urban agglomerations, the exploration of the state of ecological security at the scale of urban agglomerations is of great significance. This study considered the Lanzhou-Xining Urban Agglomeration as the research area, based on the land use data in 2000, 2005, 2010, 2015, and 2020. At the same time, the landscape ecological risk index was introduced. The land use change characteristics of the Lanzhou-Xining Urban Agglomeration were analyzed by using the land use transfer matrix, the value per unit area equivalent factor method, and the bivariate spatial autocorrelation analysis method to elucidate the impacts of the changes in the ecological risk index induced by the land use transition on the value of ecosystem services. This study analyzed the land use change characteristics of the Lanzhou-Xining Urban Agglomeration and elucidated the impacts of changes in the ecological risk index on the value of ecosystem services caused by land use transformation. The results showed that:① During the period from 2000 to 2020, the land use types of the Lanzhou-Xining Urban Agglomeration were mainly dominated by grassland, cropland, and forest land. The construction land area had expanded significantly mainly from cropland and grassland, and the six land use types had strong cross-transformation. The total area of land use change was 6 646.05 km2. ② In terms of spatial changes, the spatial pattern of ecosystem service value in the Lanzhou-Xining Urban Agglomeration had not undergone obvious transformation. However, the regional variability was significant, generally showing the distribution characteristics of high in the northwest and low in the southeast. ③From the perspective of temporal change, the value of ecosystem services in the Lanzhou-Xining Urban Agglomeration showed an upward trend, with the total flow of value increasing from 186.459 billion yuan to 192.156 billion yuan, with a total value-added of 5.697 billion yuan. ④ There was a rising trend in the overall ecological risk index of the Lanzhou-Xining Urban Agglomeration over the past 20 years. Low ecological risk areas and lower ecological risk areas dominated the ecological risk areas. There was a significant positive correlation between the value of ecosystem services and the ecological risk index. This study aimed to reveal the understanding of the impacts of land-use practices on ecosystem service values and ecological risks, to provide important references for regional ecological risk management and land-use policy formulation, and thus to promote the high-quality development of the ecological environment in the Yellow River Basin.

14.
Angew Chem Int Ed Engl ; 63(35): e202402496, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-38863241

RESUMO

Promoting the hydrogen oxidation reaction (HOR) activity and poisoning tolerance of electrocatalysts is crucial for the large-scale application of hydrogen-oxygen fuel cell. However, it is severely hindered by the scaling relations among different intermediates. Herein, lattice-contracted Pt-Rh in ultrasmall ternary L12-(Pt0.9Rh0.1)3V intermetallic nanoparticles (~2.2 nm) were fabricated to promote the HOR performances through an oxides self-confined growth strategy. The prepared (Pt0.9Rh0.1)3V displayed 5.5/3.7 times promotion in HOR mass/specific activity than Pt/C in pure H2 and dramatically limited activity attenuation in 1000 ppm CO/H2 mixture. In situ Raman spectra tracked the superior anti-CO* capability as a result of compressive strained Pt, and the adsorption of oxygen-containing species was promoted due to the dual-functional effect. Further assisted by density functional theory calculations, both the adsorption of H* and CO* on (Pt0.9Rh0.1)3V were reduced compared with that of Pt due to lattice contraction, while the adsorption of OH* was enhanced by introducing oxyphilic Rh sites. This work provides an effective tactic to stimulate the electrocatalytic performances by optimizing the adsorption of different intermediates severally.

15.
ACS Appl Mater Interfaces ; 16(27): 35353-35360, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38940538

RESUMO

Thermoelectric generators (TEGs) are environmentally friendly energy harvesting technologies that hold great promise in the field of self-powered electronics and sensing. However, the current development of thermoelectric (TE) devices has largely lagged behind the development of thermoelectric materials, especially in the preparation of thermoelectric components with customizable shapes and excellent properties, which largely limits their practical applications. These issues can be effectively addressed by using 3D printing technology. Here, we print multiple p-type thermoelectric legs (pins) consecutively with this simple technique, and the printed TEGs have excellent thermal potential (288 µV K-1 at room temperature) and excellent temperature response properties, which exhibited an output voltage of 127.94 mV at a temperature difference (ΔT) of 40 K. The 3D-printed thermoelectric generator enables the collection of thermal energy. In addition, the device has excellent temperature sensing characteristics, and this temperature signal to electrical signal conversion is very rapid, which enables temperature sensing alarms in a wide temperature domain. Combining these features, an energy harvesting and electrical alarm concept for home-scale applications is proposed, which is expected to provide a diverse research idea for the application of next-generation thermoelectric devices.

16.
Ecotoxicol Environ Saf ; 281: 116563, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38878560

RESUMO

Evodiamine (EVO), the main active alkaloid in Evodia rutaecarpa, was shown to exert various pharmacological activities, especially anti-tumor. Currently, it is considered a potential anti-cancer drug due to its excellent anti-tumor activity, which unfortunately has adverse reactions, such as the risk of liver and kidney injury, when Evodia rutaecarpa containing EVO is used clinically. In the present study, we aim to clarify the potential toxic target organs and toxicity mechanism of EVO, an active monomer in Evodia rutaecarpa, and to develop mitigation strategies for its toxicity mechanism. Transcriptome analysis and related experiments showed that the PI3K/Akt pathway induced by calcium overload was an important step in EVO-induced apoptosis of renal cells. Specifically, intracellular calcium ions were increased, and mitochondrial calcium ions were decreased. In addition, EVO-induced calcium overload was associated with TRPV1 receptor activation. In vivo TRPV1 antagonist and calcium chelator effects were observed to significantly reduce body weight loss and renal damage in mice due to EVO toxicity. The potential nephrotoxicity of EVO was further confirmed by an in vivo test. In conclusion, TRPV1-mediated calcium overload-induced apoptosis is one of the mechanisms contributing to the nephrotoxicity of EVO due to its toxicity, whereas maintaining body calcium homeostasis is an effective measure to reduce toxicity. These studies suggest that the clinical use of EVO-containing herbal medicines should pay due attention to the changes in renal function of patients as well as the off-target effects of the drugs.


Assuntos
Apoptose , Cálcio , Evodia , Homeostase , Rim , Quinazolinas , Quinazolinas/toxicidade , Quinazolinas/farmacologia , Animais , Homeostase/efeitos dos fármacos , Cálcio/metabolismo , Camundongos , Apoptose/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Evodia/química , Masculino , Canais de Cátion TRPV/metabolismo , Quelantes de Cálcio/farmacologia
17.
Phys Chem Chem Phys ; 26(23): 16637-16645, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38808387

RESUMO

The rapid recombination of photogenerated electrons and holes greatly limits the efficiency of photocatalyst based on semiconductor. In order to address this issue, we predicted a novel ferroelectric polarized heterojunction photocatalyst, CdS/In2Se3, which enables the spontaneous overall water splitting reaction. The CdS/In2Se3 heterojunction exhibits a band-edge staggered alignment and it is easy to form a direct Z-scheme charge transfer pathway. Besides, the built-in electric field (Eint) in the CdS/In2Se3 heterojunction promoted the charge transfer of CdS/In2Se3, leading to an improved separating efficiency of photo-generated carriers. Moreover, the vertical intrinsic polarized electric field (Ep) not only alters the position of the band edge but also reduces the bandgap limitations commonly associated with photocatalytic materials. Furthermore, the CdS/In2Se3 heterojunctions demonstrate separate catalytic activity for the hydrogen evolution reaction (HER) on the surface of the CdS monolayer and oxygen evolution reaction (OER) on the surface of In2Se3, respectively. Notably, the CdS/In2Se3-down configuration enables spontaneous photocatalytic water splitting in pH = 7, while the CdS/In2Se3-up configuration efficiently facilitates the HER process. This study highlights the significant advantages of CdS/In2Se3 heterojunctions as photocatalytic materials, offering unique insights into the development and research of this promising heterojunction architecture.

18.
J Magn Reson Imaging ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777575

RESUMO

BACKGROUND: Neonates with immature auditory function (eg, weak/absent middle ear muscle reflex) could conceivably be vulnerable to noise-induced hearing loss; however, it is unclear if neonates show evidence of hearing loss following MRI acoustic noise exposure. PURPOSE: To explore the auditory effects of MRI acoustic noise in neonates. STUDY TYPE: Prospective. SUBJECTS: Two independent cohorts of neonates (N = 19 and N = 18; mean gestational-age, 38.75 ± 2.18 and 39.01 ± 1.83 weeks). FIELD STRENGTH/SEQUENCE: T1-weighted three-dimensional gradient-echo sequence, T2-weighted fast spin-echo sequence, single-shot echo-planar imaging-based diffusion-tensor imaging, single-shot echo-planar imaging-based diffusion-kurtosis imaging and T2-weighted fluid-attenuated inversion recovery sequence at 3.0 T. ASSESSMENT: All neonates wore ear protection during scan protocols lasted ~40 minutes. Equivalent sound pressure levels (SPLs) were measured for both cohorts. In cohort1, left- and right-ear auditory brainstem response (ABR) was measured before (baseline) and after (follow-up) MRI, included assessment of ABR threshold, wave I, III and V latencies and interpeak interval to determine the functional status of auditory nerve and brainstem. In cohort2, baseline and follow-up left- and right-ear distortion product otoacoustic emission (DPOAE) amplitudes were assessed at 1.2 to 7.0 kHz to determine cochlear function. STATISTICAL TEST: Wilcoxon signed-rank or paired t-tests with Bonferroni's correction were used to compare the differences between baseline and follow-up ABR and DPOAE measures. RESULTS: Equivalent SPLs ranged from 103.5 to 113.6 dBA. No significant differences between baseline and follow-up were detected in left- or right-ear ABR measures (P > 0.999, Bonferroni corrected) in cohort1, or in DPOAE levels at 1.2 to 7.0 kHz in cohort2 (all P > 0.999 Bonferroni corrected except for left-ear levels at 3.5 and 7.0 kHz with corrected P = 0.138 and P = 0.533). DATA CONCLUSION: A single 40-minute 3-T MRI with equivalent SPLs of 103.5-113.6 dBA did not result in significant transient disruption of auditory function, as measured by ABR and DPOAE, in neonates with adequate hearing protection. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 5.

19.
Int J Med Sci ; 21(7): 1250-1256, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38818475

RESUMO

Background: Recovery time is a crucial factor in ensuring the safety and effectiveness of both patients and endoscopy centers. Propofol is often preferred due to its fast onset and minimal side effects. Remimazolam is a new intravenous sedative agent, characterized by its rapid onset of action, quick recovery and organ-independent metabolism. Importantly, its effect can be specifically antagonized by flumazenil. The primary goal of this study is to compare the recovery time of remimazolam besylate and propofol anesthesia during endoscopic procedures in elderly patients. Methods: 60 patients aged 65-95 years who underwent gastrointestinal endoscopy were randomly and equally assigned to two groups: the remimazolam group (Group R) and the propofol group (Group P). The primary measure was the recovery time, defined as the time from discontinuing remimazolam or propofol until reaching an Observer's Assessment of Alertness and Sedation scale (OAA/S) score of 5 (responds readily to name spoken in normal tone). The time required to achieve an OAA/S score of 3 (responds after name spoken loudly or repeatedly along with glazed marked ptosis) was also recorded and compared. Results: The recovery time for Group R (2.6 ± 1.6 min) was significantly shorter than that for Group P (10.8 ± 3.0 min), with a 95% confidence interval (CI): 6.949-9.431 min, p <0.001. Similarly, the time to attain an OAA/S score of 3 was significantly less in Group R (1.6 ± 0.9 min) compared to Group P (9.6 ± 2.6 min), with a 95% CI: 6.930-8.957 min, p <0.001. Conclusion: Our study demonstrated that remimazolam anesthesia combined with flumazenil antagonism causes a shorter recovery time for elderly patients undergoing gastrointestinal endoscopy compared to propofol. Remimazolam followed by flumazenil antagonism provides a promising alternative to propofol for geriatric patients, particularly during gastrointestinal endoscopy.


Assuntos
Período de Recuperação da Anestesia , Benzodiazepinas , Endoscopia Gastrointestinal , Hipnóticos e Sedativos , Propofol , Humanos , Idoso , Propofol/administração & dosagem , Masculino , Feminino , Idoso de 80 Anos ou mais , Endoscopia Gastrointestinal/métodos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/efeitos adversos , Benzodiazepinas/uso terapêutico
20.
ISME Commun ; 4(1): ycae058, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38770058

RESUMO

Extracellular electron transfer (EET) of microorganisms is a major driver of the microbial growth and metabolism, including reactions involved in the cycling of C, N, and Fe in anaerobic environments such as soils and sediments. Understanding the mechanisms of EET, as well as knowing which organisms are EET-capable (or can become so) is fundamental to electromicrobiology and geomicrobiology. In general, Gram-positive bacteria very seldomly perform EET due to their thick non-conductive cell wall. Here, we report that a Gram-positive Clostridium intestinale (C.i) attained EET-capability for ethanol metabolism only after forming chimera with electroactive Geobacter sulfurreducens (G.s). Mechanism analyses demonstrated that the EET was possible after the cell fusion of the two species was achieved. Under these conditions, the ethanol metabolism pathway of C.i was integrated by the EET pathway of G.s, by which achieved the oxidation of ethanol for the subsequent reduction of extracellular electron acceptors in the coculture. Our study displays a new approach to perform EET for Gram-positive bacteria via recruiting the EET pathway of an electroactive bacterium, which suggests a previously unanticipated prevalence of EET in the microbial world. These findings also provide new perspectives to understand the energetic coupling between bacterial species and the ecology of interspecies mutualisms.

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