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1.
Mol Cell ; 67(4): 566-578.e10, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28803781

RESUMO

50 years ago, Vincent Allfrey and colleagues discovered that lymphocyte activation triggers massive acetylation of chromatin. However, the molecular mechanisms driving epigenetic accessibility are still unknown. We here show that stimulated lymphocytes decondense chromatin by three differentially regulated steps. First, chromatin is repositioned away from the nuclear periphery in response to global acetylation. Second, histone nanodomain clusters decompact into mononucleosome fibers through a mechanism that requires Myc and continual energy input. Single-molecule imaging shows that this step lowers transcription factor residence time and non-specific collisions during sampling for DNA targets. Third, chromatin interactions shift from long range to predominantly short range, and CTCF-mediated loops and contact domains double in numbers. This architectural change facilitates cognate promoter-enhancer contacts and also requires Myc and continual ATP production. Our results thus define the nature and transcriptional impact of chromatin decondensation and reveal an unexpected role for Myc in the establishment of nuclear topology in mammalian cells.


Assuntos
Linfócitos B/metabolismo , Ciclo Celular , Núcleo Celular/metabolismo , Montagem e Desmontagem da Cromatina , Cromatina/metabolismo , Histonas/metabolismo , Ativação Linfocitária , Proteínas Proto-Oncogênicas c-myc/metabolismo , Acetilcoenzima A/metabolismo , Acetilação , Trifosfato de Adenosina/metabolismo , Animais , Linfócitos B/imunologia , Linhagem Celular , Cromatina/química , Cromatina/genética , Metilação de DNA , Epigênese Genética , Genótipo , Histonas/química , Imunidade Humoral , Metilação , Camundongos Endogâmicos C57BL , Camundongos Knockout , Conformação de Ácido Nucleico , Fenótipo , Domínios e Motivos de Interação entre Proteínas , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-myc/química , Proteínas Proto-Oncogênicas c-myc/genética , Imagem Individual de Molécula , Relação Estrutura-Atividade , Fatores de Tempo , Transcrição Gênica
2.
Nano Lett ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39361493

RESUMO

Time reversal symmetry breaking in superconductors, resulting from external magnetic fields or spontaneous magnetization, often leads to unconventional superconducting properties. In this way, an intrinsic phenomenon called the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state may be realized by the Zeeman effect. Here, we construct the FFLO state in an artificial CrOCl/NbSe2 van der Waals (vdW) heterostructure by utilizing the superconducting proximity effect of NbSe2 flakes. The proximity-induced superconductivity demonstrates a considerably weak gap of about 0.12 meV, and the in-plane upper critical field reveals the behavior of the FFLO state. First-principles calculations uncover the origin of the proximitized superconductivity, which indicates the importance of Cr vacancies or line defects in CrOCl. Moreover, the FFLO state could be induced by the inherent large spin splitting in CrOCl. Our findings not only provide a practical scheme for constructing the FFLO state but also inspire the discovery of an exotic FFLO state in other two-dimensional vdW heterostructures.

3.
Genes Dev ; 31(17): 1795-1808, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28982762

RESUMO

Transcription factor (TF)-directed enhanceosome assembly constitutes a fundamental regulatory mechanism driving spatiotemporal gene expression programs during animal development. Despite decades of study, we know little about the dynamics or order of events animating TF assembly at cis-regulatory elements in living cells and the long-range molecular "dialog" between enhancers and promoters. Here, combining genetic, genomic, and imaging approaches, we characterize a complex long-range enhancer cluster governing Krüppel-like factor 4 (Klf4) expression in naïve pluripotency. Genome editing by CRISPR/Cas9 revealed that OCT4 and SOX2 safeguard an accessible chromatin neighborhood to assist the binding of other TFs/cofactors to the enhancer. Single-molecule live-cell imaging uncovered that two naïve pluripotency TFs, STAT3 and ESRRB, interrogate chromatin in a highly dynamic manner, in which SOX2 promotes ESRRB target search and chromatin-binding dynamics through a direct protein-tethering mechanism. Together, our results support a highly dynamic yet intrinsically ordered enhanceosome assembly to maintain the finely balanced transcription program underlying naïve pluripotency.


Assuntos
Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica/genética , Fatores de Transcrição Kruppel-Like/genética , Células-Tronco Pluripotentes/fisiologia , Animais , Sítios de Ligação , Cromatina/metabolismo , Células-Tronco Embrionárias , Fator 4 Semelhante a Kruppel , Camundongos , Fator 3 de Transcrição de Octâmero/metabolismo , Ligação Proteica , Receptores de Estrogênio/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Fator de Transcrição STAT3/metabolismo , Fatores de Transcrição/metabolismo
4.
Small ; 20(32): e2311782, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38497813

RESUMO

With the development of electric vehicles, exploiting anode materials with high capacity and fast charging capability is an urgent requirement for lithium-ion batteries (LIBs). Borophene, with the merits of high capacity, high electronic conductivity and fast diffusion kinetics, holds great potential as anode for LIBs. However, it is difficult to fabricate for the intrinsic electron-deficiency of boron atom. Herein, heterogeneous-structured MoB2 (h-MoB2) with amorphous shell and crystalline core, is prepared by solid phase molten salt method. As demonstrated, crystalline core can encapsulate the honeycomb borophene within two adjacent Mo atoms, and amorphous shell can accommodate more lithium ions to strengthen the lithium storage capacity and diffusion kinetics. According to theoretical calculations, the lithium adsorption energy in MoB2 is about -2.7 eV, and the lithium diffusion energy barrier in MoB2 is calculated to be 0.199 eV, guaranteeing the enhanced adsorption capability and fast diffusion kinetic behavior of Li+ ions. As a result, h-MoB2 anode presents high capacity of 798 mAh g-1 at 0.1 A g-1, excellent rate performance of 183 mAh g-1 at 5 A g-1 and long-term cyclic stability for 1200 cycles. This work may inspire ideas for the fabrication of borophene analogs and two-dimensional metal borides.

5.
Opt Lett ; 49(11): 2873-2876, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824280

RESUMO

In the space gravitational wave detection, numerous laser interferometer strategies have been proposed to reduce the complexity of traditional heterodyne interferometers. Previously, we proposed a novel interferometric strategy and simulated its effectiveness, called CAM (constant amplitude modulation) heterodyne interferometry. Compared with other methods, the CAM can introduce the OPT (optical pilot tone) for the common-mode noise rejection. In this paper, we present the first, to our knowledge, experimental verification of this technique. The experimental results indicate that OPT can successfully eliminate sampling jitter, enabling the corrected noise to meet the requirements of space gravitational wave detection. This provides a new approach for further optical optimization and noise elimination in the future.

6.
Chemistry ; 30(13): e202303424, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38116816

RESUMO

High-efficacy recycling of spent lithium cobalt oxide (LiCoO2 ) batteries is one of the key tasks in realizing a global resource security strategy due to the rareness of lithium (Li) and cobalt (Co) resources. However, it is of great significance to develop the innovative recycle methods for spent LiCoO2 , simultaneously realizing the efficient recovery of valuable elements and the regeneration of high-performance LiCoO2 . Herein, a novel strategy of regenerating LiCoO2 cathode is proposed, which involves the preparation of micro-spherical aluminum (Al)-doped lithium-lacked precursor (Li2x Co1-x-y Al2/3y CO3, remarked as "PLCAC") via ammonium bicarbonate coprecipitation. The comprehensive conditions affecting particle growth kinetics, morphology and particle size the has been investigated in detail by physical characterizations and electrochemical measurements. And the optimized Al-doped LiCoO2 materials with high-density sphericity (LiCo1-z Alz O2 , remarked as "LCAO") shows a high initial specific capacity of 161 mAh g-1 at 0.1 C and excellent capacity retention of 99.5 % within 100 cycles at 1 C in the voltage range of 2.8 to 4.3 V. Our work provides valuable insights into the featured design of LiCoO2 precursors and cathode materials from spent LiCoO2 batteries, potentially guaranteeing the high-efficacy recycling and utilization of strategic resources.

7.
Chemistry ; 30(25): e202304296, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38380537

RESUMO

Sodium/potassium-ion batteries (NIBs and KIBs) are considered the most promising candidates for lithium-ion batteries in energy storage fields. Tin sulfide (SnS2) is regarded as an attractive negative candidate for NIBs and KIBs thanks to its superior power density, high-rate performance and natural richness. Nevertheless, the slow dynamics, the enormous volume change and the decomposition of polysulfide intermediates limit its practical application. Herein, microcubes SnS2 were prepared through sacrificial MnCO3 template-assisted and a facile solvothermal reaction strategy and their performance was investigated in Na and K-based cells. The unique hollow cubic structure and well-confined SnS2 nanosheets play an important role in Na+/K+ rapid kinetic and alleviating volume change. The effect of the carbon additives (Super P/C65) on the electrochemical properties were investigated thoroughly. The in operando and ex-situ characterization provide a piece of direct evidence to clarify the storage mechanism of such conversion-alloying type negative electrode materials.

8.
Eur Radiol ; 34(1): 715-723, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37581653

RESUMO

OBJECTIVES: Microwave ablation (MWA) has achieved excellent long-term efficacy in treating unifocal papillary thyroid microcarcinoma (UPTMC). The therapeutic effect of this treatment on multifocal papillary thyroid microcarcinoma (MPTMC) is unknown. Therefore, we evaluated the long-term efficacy of MWA for low-risk MPTMC and to provide evidence-based medicine for the revision of clinical guidelines. METHODS: This study included 66 MPTMC patients with a total of 158 lesions, all of whom received MWA. We collected and retrospectively analyzed the patients' follow-up data before MWA, at 1, 3, 6, and 12 months posttreatment and every 6 months thereafter until 5 years posttreatment. We evaluated the MWA complication rate, technical success rate (TSR), lesion volume reduction rate (VRR), and complete disappearance rate (CDR) during follow-up and in those patients with tumor progression and delayed surgery. RESULTS: After 60 months of follow-up, all 158 lesions disappeared in 66 patients, and the volume was reduced from 43.82 mm3 to 0.00 mm3. The TSR and VRR were both 100%. The CDRs at 1 year, 2 years, and 3 years were 57.59%, 93.67%, and 100%, respectively. The complication rate was 3.03% (2/66), and the incidence of tumor progression was 3.03% (2/66), including one new intrathyroidal lesion and one cervical lymph node metastasis (LNM). These lesions were retreated with MWA, and the lesions disappeared during the follow-up period. CONCLUSIONS: Ultrasound-guided MWA for low-risk MPTMC is safe and effective and may serve as an alternative option for patients who refuse surgery or active surveillance (AS). CLINICAL RELEVANCE STATEMENT: This study concludes that ultrasound-guided microwave ablation for low-risk multifocal papillary thyroid microcarcinoma is safe and effective and may serve as an alternative option for patients who refuse surgery or active surveillance. KEY POINTS: • Ultrasound-guided microwave ablation for low-risk multifocal papillary thyroid microcarcinoma is safe and effective. • During 5 years of follow-up, multifocal papillary thyroid microcarcinoma patients treated with microwave ablation had a favorable prognosis. • To provide evidence-based medicine for the revision of clinical guidelines.


Assuntos
Carcinoma Papilar , Micro-Ondas , Neoplasias da Glândula Tireoide , Humanos , Seguimentos , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Resultado do Tratamento , Ultrassonografia de Intervenção
9.
Environ Res ; 251(Pt 2): 118721, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490624

RESUMO

The gradual increase in cattle farming has led to a huge production of cattle manure (CM), but the conventional treatment methods are less efficient. In this study, the treatment method of anaerobic digestion (AD) of high-solids CM by combining nanobubble water (NBW) with different gases was proposed to present a new idea for the reduction, harmlessness, and resourcefulness of CM. It was found that the performance of the digester with added NBW was better than the control. Among them, the cumulative methane yield T-Air: 227.09 mL g-1 VSadded and T-CO2: 226.12 mL g-1 VSadded increased by 17.72 % and 17.22 %, respectively, compared with the control T: 192.90 mL g-1 VSadded under thermophilic conditions. Under mesophilic conditions, M-Air: 162.39 mL g-1 VSadded increased by 9.68 % compared with control M: 148.05 mL g-1 VSadded. Microbial communities analyzed at the genus level revealed that the relative abundance of bacteria favorable to hydrolysis and acid-producing processes, such as Defluviitalea, Haloplasma, and Bacillus, increased to varying degrees. Moreover, the relative abundance of archaea favorable for methanogenesis, such as Methanoculleus, Methanobrevibacter, and Methanosarcina, also increased to varying degrees. Therefore, the addition of NBW promoted the hydrolysis of high-solids CM, enhanced the stability of the reaction, improved the methanogenic performance, and increased the RA of favorable genera, which ultimately led to a better performance of the AD of high-solids CM.


Assuntos
Esterco , Metano , Esterco/microbiologia , Animais , Bovinos , Anaerobiose , Metano/metabolismo , Metano/análise , Água/química , Reatores Biológicos , Bactérias/metabolismo
10.
J Asian Nat Prod Res ; : 1-18, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979968

RESUMO

In this study, based on Walker 256 in vitro experiments, CCK-8 assay, clone formation assay, wound healing assay, and flow cytometry were used to detect cell apoptosis and cell cycle. It was found that schisandrin may have significant anti-tumor effects in vitro by inhibiting TGF-ß/Smad signaling pathway. In addition, in vivo experiments, immunohistochemistry was used to observe the expression of HIF-1α, VEGF and VEGFR-2 in tumor tissues. It was found that schisandrin could significantly improve the immunosuppression induced by 5-Fu and enhance the antitumor effect of 5-Fu. The mechanism may be related to the inhibition of Wnt-1/ß-catenin signaling pathway.

11.
J Environ Manage ; 370: 123026, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39447368

RESUMO

The filling substrate is one of key factors influencing effectiveness of sulfate reducing packed-bed bioreactor (SRPB) treating acid mine drainage (AMD). The effects of four substrates (i.e. quartz sand, steel residue, biochar, and peanut shell) on remediation performance and sulfur transformation of SRPB treating AMD was studied. The results showed that steel residue and biochar improved sulfate reduction efficiency (61% and 49%) compared to quartz sand (32%), whereas peanut shell inhibited sulfate reduction efficiency (19%), attributed to its decomposition process leading to a severe accumulation of acetic acid. More amounts of sulfides generated in steel residue bioreactor were converted into acid volatile sulfide and elemental sulfur, resulting in a significant decrease in dissolved sulfide in the effluent. Metals (Fe, Al, Zn, Cd and Cr) except for Mn were effectively immobilized in the bioreactors, particularly for Al and Cd. Sulfate reducing bacteria and sulfide oxidizing bacteria lived symbiotically in all bioreactors which exhibited similar heterogeneity in microbial distribution and function, i.e. bacterial sulfate reduction mainly occurring in bottom-middle layers and photoautotrophic sulfide oxidation in upper layer close to outlet. The microbial response mechanism to various substrate environments was revealed through co-occurrence networks analysis. This study suggests that attention should be paid to the inhibitory effect of acetic acid accumulation on sulfate reduction when using sole lignocellulosic waste (peanut shell), and steel residue and biochar could be utilized as filling substances to promote sulfate reduction.

12.
Molecules ; 29(14)2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39064918

RESUMO

The rapid growth of electronic devices, electric vehicles, and mobile energy storage has produced large quantities of spent batteries, leading to significant environmental issues and a shortage of lithium resources. Recycling spent batteries has become urgent to protect the environment. The key to treating spent lithium-ion batteries is to implement green and efficient regeneration. This study proposes a recycling method for the direct regeneration of spent lithium iron phosphate (LFP) batteries using hydrothermal reduction. Ascorbic acid (AA) was used as a low-cost and environmentally friendly reductant to reduce Fe3+ in spent LiFePO4. We also investigated the role of AA in the hydrothermal process and its effects on the electrochemical properties of the regenerated LiFePO4 cathode material (AA-SR-LFP). The results showed that the hydrothermal reduction direct regeneration method successfully produced AA-SR-LFP with good crystallinity and electrochemical properties. AA-SR-LFP exhibited excellent electrochemical properties, with an initial discharge specific capacity of 144.4 mAh g-1 at 1 C and a capacity retention rate of 98.6% after 100 cycles. In summary, the hydrothermal reduction direct regeneration method effectively repairs the defects in the chemical composition and crystal structure of spent LiFePO4. It can be regarded as a green and effective regeneration approach for spent LiFePO4 cathode materials.

13.
J Am Chem Soc ; 145(42): 23000-23013, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37842926

RESUMO

Rhodamine dyes are excellent scaffolds for developing a broad range of fluorescent probes. A key property of rhodamines is their equilibrium between a colorless lactone and fluorescent zwitterion. Tuning the lactone-zwitterion equilibrium constant (KL-Z) can optimize dye properties for specific biological applications. Here, we use known and novel organic chemistry to prepare a comprehensive collection of rhodamine dyes to elucidate the structure-activity relationships that govern KL-Z. We discovered that the auxochrome substituent strongly affects the lactone-zwitterion equilibrium, providing a roadmap for the rational design of improved rhodamine dyes. Electron-donating auxochromes, such as julolidine, work in tandem with fluorinated pendant phenyl rings to yield bright, red-shifted fluorophores for live-cell single-particle tracking (SPT) and multicolor imaging. The N-aryl auxochrome combined with fluorination yields red-shifted Förster resonance energy transfer (FRET) quencher dyes useful for creating a new semisynthetic indicator to sense cAMP using fluorescence lifetime imaging microscopy (FLIM). Together, this work expands the synthetic methods available for rhodamine synthesis, generates new reagents for advanced fluorescence imaging experiments, and describes structure-activity relationships that will guide the design of future probes.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes , Corantes Fluorescentes/química , Rodaminas/química , Microscopia de Fluorescência/métodos , Lactonas
14.
Small ; 19(38): e2302386, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37196415

RESUMO

Sluggish redox kinetics and shuttle effect of polysulfides hinder the extensive application of the lithium-sulfur batteries (LSBs). Herein a functional heterostructure of boron nitride (BN) and MXene with an alternately layered structure (BN@MXene) is designed as separator interlayer. High efficiency Li+ transmission, uniform lithium deposition, strong adsorption, and efficient catalytic conversion activities of lithium polysulfides (LiPSs) realized by this heterostructure are confirmed by experiments and theoretical calculations. The alternately layered structure provides unblocked ion transmission channels and abundant active sites to accelerate the polysulfides redox kinetics with reduced energy barriers of oxidation and reduction reactions. As a result, the LSBs deliver an initial discharge capacity of up to 1273.9 mAh g-1 at 0.2 °C and a low decay of 0.058% per cycle in long-term cycling up to 700 cycles at 1 °C. This work provides an effective designing strategy to accelerate the polysulfides redox kinetics for advanced Li-S electrochemical system.

15.
Nat Methods ; 17(4): 430-436, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32203384

RESUMO

To image the accessible genome at nanometer scale in situ, we developed three-dimensional assay for transposase-accessible chromatin-photoactivated localization microscopy (3D ATAC-PALM) that integrates an assay for transposase-accessible chromatin with visualization, PALM super-resolution imaging and lattice light-sheet microscopy. Multiplexed with oligopaint DNA-fluorescence in situ hybridization (FISH), RNA-FISH and protein fluorescence, 3D ATAC-PALM connected microscopy and genomic data, revealing spatially segregated accessible chromatin domains (ACDs) that enclose active chromatin and transcribed genes. Using these methods to analyze genetically perturbed cells, we demonstrated that genome architectural protein CTCF prevents excessive clustering of accessible chromatin and decompacts ACDs. These results highlight 3D ATAC-PALM as a useful tool to probe the structure and organizing mechanism of the genome.


Assuntos
DNA/metabolismo , Genômica/métodos , Hibridização in Situ Fluorescente/métodos , Microscopia/métodos , Coloração Cromossômica , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Processamento de Imagem Assistida por Computador , Análise de Sequência de DNA/métodos
16.
Opt Express ; 31(24): 40658-40674, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041360

RESUMO

Metasurfaces have enabled precise electromagnetic (EM) wave manipulation with strong potential to obtain unprecedented functionalities and multifunctional behavior in flat optical devices. One promising aspect to achieve multifunction is polarization-dependent metadevices enabled by simultaneous phase control over orthogonally polarized waves. Among these, metasurfaces with geometric phase shows their natural and robust phase control ability over different circularly polarized waves. However, the phase responses under the circularly polarized incidence are locked to be opposite with each other, resulting in limited multifunctionality. In this study, we propose what we believe to be a novel transmission-type microwave metadevice constructed by linear-to-circular metasurface and spin-decoupled metasurface. By endowing independent phase adjustment capability to each unit structure in a spin-decoupled metasurface, the metadevice can reconfigure arbitrary phase wavefronts under orthogonal polarization state incidence, thereby achieving flexible multifunctionality. As a proof-of-concept, the feasibility and reliability of proposed metasurfaces were verified by simulating multifunctional directional deflection, off-axis focusing, and focused vortex beam generation. Finally, the multifunctional manipulation capability of the metadevice is successfully demonstrated by actually measuring the generation of orbital angular momentum modes. This work is expected to drive the application development of metasurface devices in wireless communication.

17.
Eur Radiol ; 33(4): 2407-2414, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36472698

RESUMO

OBJECTIVES: To investigate the value of contrast-enhanced ultrasound (CEUS) combined with feeding artery ablation in the microwave ablation (MWA) of large solid benign thyroid nodules (LSBTNs) with a diameter ≥ 4 cm. METHODS: We retrospectively analyzed 122 patients with LSBTN ≥ 4 cm in diameter treated with MWA. During evaluations before and after MWA, 53 patients who underwent conventional ultrasound examination were classified as the routine group, and 69 patients who underwent CEUS combined with feeding artery ablation were classified as the union group. The differences in ablation energy required per milliliter (AERPM), complication rate, regrowth rate, and volume reduction rate (VRR) were compared between the two groups. RESULTS: The AERPM of the union group was significantly less than that of the routine group (956.3 ± 38.5 J/mL vs. 1025.9 ± 121.5 J/mL, p < 0.001). The complication rate of the routine group was significantly higher than that of the union group (13.2% vs. 2.9%, p = 0.031). The regrowth rate of the routine group (22.6%, 12/53) was significantly higher than that of the union group (7.2%, 5/69) (p = 0.015). At the 1st, 3rd, 6th, 12th, 18th, and 24th month after ablation, the mean VRRs of the routine group were significantly less than those of the union group, with p values of < 0.001, < 0.001, 0.002, 0.007, 0.013, and < 0.001, respectively. CONCLUSIONS: The application of CEUS combined with feeding artery ablation in the MWA of LSBTNs is helpful to reduce the regrowth rate, improve the ablation efficiency, and reduce bleeding. KEY POINTS: • CEUS combined with feeding artery ablation in MWA of LSBTNs is helpful to reduce regrowth rate. • CEUS combined with feeding artery ablation can help improve ablation efficiency than conventional ultrasound in LSBTNs. • CEUS combined with feeding artery ablation helps reduce the incidence of bleeding during MWA.


Assuntos
Ablação por Cateter , Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/cirurgia , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Artérias
18.
Environ Res ; 229: 115751, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-36966997

RESUMO

Mining and smelting are the main sources of soil heavy metal pollution. Leaching and release of heavy metals in soils has been extensively studied. However, there are few researches on the release behavior of heavy metals from the Angle of mineralogy of smelting slag. This study focuses on the pollution of arsenic and chromium by traditional pyrometallurgical lead-zinc smelting slag in southwest China. Based on the mineralogy of smelting slag, the release behavior of heavy metals in smelting slag was studied. As and Cr deposit minerals were identified by MLA analysis, and the weathering degree and bioavailability of As and Cr deposit minerals were analyzed. The results showed that the weathering degree of slag was positively correlated with the bioavailability of heavy metals. The leaching experiment results showed that the higher pH was beneficial to the release of As and Cr. It was found that the chemical forms of As and Cr changed from relatively stable forms to easily released forms (As5+ to As3+ and Cr3+ to Cr6+) by characterizing the metallurgical slag during leaching. In the transformation process, the S in the pyrite as the enclosing layer is eventually oxidized to SO42-, which will accelerate the dissolution of the enclosing mineral. SO42- will occupy the adsorption site of As on the mineral surface, thus reducing the adsorption amount of As on the mineral surface. Fe is finally oxidized to Fe2O3, and the increase of Fe2O3 content in the waste residue will produce strong adsorption effect on Cr6+ and slow down the release of Cr6+. The results show that the release of As and Cr is controlled by the pyrite coating.


Assuntos
Metais Pesados , Poluentes do Solo , Zinco/análise , Disponibilidade Biológica , Compostos Férricos , Chumbo/análise , Metais Pesados/análise , Minerais/análise , Poluentes do Solo/análise , Monitoramento Ambiental
19.
Appl Opt ; 62(30): 8184-8189, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-38038116

RESUMO

By inserting the monolayer graphene between the balanced gain and loss layers, the graphene-incorporated quasi-parity-time (PT) symmetric structure is established. In this contribution, the introduction of graphene provides a new degree of freedom to manipulate the optical performance as well as the photonic spin Hall effect (SHE). The coherent perfect absorption (CPA)-laser mode still remains in the graphene-incorporated quasi-PT symmetric system, and the spin shift of transmitted light can be significantly enhanced (i.e., up to its upper limitation) in the vicinity of CPA-laser mode, which is 18 times larger than the value of a simple PT symmetric structure. In addition, the excitation of the CPA-laser mode and the huge spin shift of transmitted light can be achieved with the thin gain/loss layers, which will be conducive to the miniaturization of nanophotonic devices based on the photonic SHE in the future.

20.
Sensors (Basel) ; 23(11)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37299855

RESUMO

A tunable and narrow-bandwidth Q-switched ytterbium-doped fiber (YDF) laser is investigated in this paper. The non-pumped YDF acts as a saturable absorber and, together with a Sagnac loop mirror, provides a dynamic spectral-filtering grating to achieve a narrow-linewidth Q-switched output. By adjusting an etalon-based tunable fiber filter, a tunable wavelength from 1027 nm to 1033 nm is obtained. When the pump power is 1.75 W, the Q-switched laser pulses with a pulse energy of 10.45 nJ, and a repetition frequency of 11.98 kHz and spectral linewidth of 112 MHz are obtained. This work paves the way for the generation narrow-linewidth Q-switched lasers with tunable wavelengths in conventional ytterbium, erbium, and thulium fiber bands to address critical applications such as coherent detection, biomedicine, and nonlinear frequency conversion.


Assuntos
Lasers , Itérbio , Desenho de Equipamento , Luz , Érbio
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