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1.
Sensors (Basel) ; 24(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38610287

RESUMO

Fringe projection profilometry (FPP), with benefits such as high precision and a large depth of field, is a popular 3D optical measurement method widely used in precision reconstruction scenarios. However, the pixel brightness at reflective edges does not satisfy the conditions of the ideal pixel-wise phase-shifting model due to the influence of scene texture and system defocus, resulting in severe phase errors. To address this problem, we theoretically analyze the non-pixel-wise phase propagation model for texture edges and propose a reprojection strategy based on scene texture modulation. The strategy first obtains the reprojection weight mask by projecting typical FPP patterns and calculating the scene texture reflection ratio, then reprojects stripe patterns modulated by the weight mask to eliminate texture edge effects, and finally fuses coarse and refined phase maps to generate an accurate phase map. We validated the proposed method on various texture scenes, including a smooth plane, depth surface, and curved surface. Experimental results show that the root mean square error (RMSE) of the phase at the texture edge decreased by 53.32%, proving the effectiveness of the reprojection strategy in eliminating depth errors at texture edges.

2.
ACS Appl Mater Interfaces ; 16(11): 14038-14046, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38445951

RESUMO

The interplay between flexoelectric and optoelectronic characteristics provides a paradigm for studying emerging phenomena in various 2D materials. However, an effective way to induce a large and tunable strain gradient in 2D devices remains to be exploited. Herein, we propose a strategy to induce large flexoelectric effect in 2D ferroelectric CuInP2S6 by constructing a 1D-2D mixed-dimensional heterostructure. The strong flexoelectric effect is induced by enormous strain gradient up to 4.2 × 106 m-1 resulting from the underlying ZnO nanowires, which is further confirmed by the asymmetric coercive field and the red-shift in the absorption edge. The induced flexoelectric polarization efficiently boosts the self-powered photodetection performance. In addition, the improved photoresponse has a good correlation with the induced strain gradient, showing a consistent size-dependent flexoelectric effect. The mechanism of flexoelectric and optoelectronic coupling is proposed based on the Landau-Ginzburg-Devonshire double-well model, supported by density functional theory (DFT) calculations. This work provides a brand-new method to induce a strong flexoelectric effect in 2D materials, which is not restricted to crystal symmetry and thus offers unprecedented opportunities for state-of-the-art 2D devices.

3.
J Phys Chem Lett ; 15(11): 2944-2950, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38452256

RESUMO

Isotope detection is crucial for geological research, medical diagnostics, industrial production, and environmental monitoring. Various spectroscopic techniques are continually emerging for isotopic identification and accurate measurement. Herein, coherent Raman scattering (CRS) spectroscopy is developed for the quantitative detection of carbon dioxide isotopes, in which the N2+ air lasing coherently created in the interaction region is used as the probe. Benefiting from the narrow spectral width of air lasing, the Raman peaks of 12CO2 and 13CO2 can be well discerned, although their spectra partially overlap. The overlapped signals were proven to be the result of the coherent superposition of individual Raman signals. Based on that fact, a deconvolution algorithm was designed to retrieve the concentration ratio of the two isotopes. The relative error of the measurement is less than 6%. The CRS technique based on air lasing offers a potential approach for the quantitative characterization of molecular isotopes, especially in application scenarios of remote sensing or in situ detection.

4.
BMC Genomics ; 25(1): 158, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331736

RESUMO

BACKGROUND: Studies have confirmed that Infectious bovine rhinotracheitis virus (IBRV) infection induces mitochondrial damage. MicroRNAs (miRNAs) are a class of noncoding RNA molecules, which are involved in various biological processes and pathological changes associated with mitochondrial damage. It is currently unclear whether miRNAs participate in IBRV-induced mitochondrial damage in Madin-Darby bovine kidney (MDBK) cells. RESULTS: In the present study, we used high-throughput sequencing technology, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis to screen for mitochondria-related miRNAs and messenger RNAs (mRNAs). In total, 279 differentially expressed miRNAs and 832 differentially expressed mRNAs were identified in 6 hours (IBRV1) versus 24 hours (IBRV2) after IBRV infection in MDBK cells. GO and KEGG enrichment analysis revealed that 42 differentially expressed mRNAs and 348 target genes of differentially expressed miRNAs were correlated with mitochondrial damage, and the miRNA-mitochondria-related target genes regulatory network was constructed to elucidate their potential regulatory relationships. Among the 10 differentially expressed miRNAs, 8 showed expression patterns consistent with the high-throughput sequencing results. Functional validation results showed that overexpression of miR-10a and miR-182 aggravated mitochondrial damage, while inhibition of miR-10a and miR-182 alleviated mitochondrial damage. CONCLUSIONS: This study not only revealed the expression changes of miRNAs and mRNAs in IBRV-infected MDBK cells, but also revealed possible biological regulatory relationship between them. MiR-10a and miR-182 may have the potential to be developed as biomarkers for the diagnosis and treatment of IBRV. Together, Together, these data and analyses provide additional insights into the roles of miRNA and mRNA in IBRV-induced mitochondria damage.


Assuntos
Herpesvirus Bovino 1 , MicroRNAs , Animais , Bovinos , MicroRNAs/genética , MicroRNAs/metabolismo , Herpesvirus Bovino 1/genética , Células Epiteliais/metabolismo , Rim/metabolismo , Redes Reguladoras de Genes , RNA Mensageiro/genética , Perfilação da Expressão Gênica
5.
Angew Chem Int Ed Engl ; 63(11): e202319896, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38197522

RESUMO

Upgrading of polyethylene terephthalate (PET) waste into valuable oxygenated molecules is a fascinating process, yet it remains challenging. Herein, we developed a two-step strategy involving methanolysis of PET to dimethyl terephthalate (DMT), followed by hydrogenation of DMT to produce the high-valued chemical methyl p-methyl benzoate (MMB) using a fixed-bed reactor and a Cu/ZrO2 catalyst. Interestingly, we discovered the phase structure of ZrO2 significantly regulates the selectivity of products. Cu supported on monoclinic ZrO2 (5 %Cu/m-ZrO2 ) exhibits an exceptional selectivity of 86 % for conversion of DMT to MMB, while Cu supported on tetragonal ZrO2 (5 %Cu/t-ZrO2 ) predominantly produces p-xylene (PX) with selectivity of 75 %. The superior selectivity of MMB over Cu/m-ZrO2 can be attributed to the weaker acid sites present on m-ZrO2 compared to t-ZrO2 . This weak acidity of m-ZrO2 leads to a moderate adsorption capability of MMB, and facilitating its desorption. Furthermore, DFT calculations reveal Cu/m-ZrO2 catalyst shows a higher effective energy barrier for cleavage of second C-O bond compared to Cu/t-ZrO2 catalyst; this distinction ensures the high selectivity of MMB. This catalyst not only presents an approach for upgrading of PET waste into fine chemicals but also offers a strategy for controlling the primary product in a multistep hydrogenation reaction.

6.
Angew Chem Int Ed Engl ; 63(8): e202316874, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38179842

RESUMO

Converting CO2 to olefins is an ideal route to achieve carbon neutrality. However, selective hydrogenation to light olefins, especially single-component olefin, while reducing CH4 formation remains a great challenge. Herein, we developed ZnZrOx /SSZ-13 tandem catalyst for the highly selective hydrogenation of CO2 to light olefins. This catalyst shows C2 = -C4 = and propylene selectivity up to 89.4 % and 52 %, respectively, while CH4 is suppressed down to 2 %, and there is no obvious deactivation. It is demonstrated that the isolated moderate Brønsted acid sites (BAS) of SSZ-13 promotes the rapid conversion of intermediate species derived from ZnZrOx , thereby enhancing the kinetic coupling of the reactions and inhibit the formation of alkanes and improve the light olefins selectivity. Besides, the weaker BAS of SSZ-13 promote the conversion of intermediates into aromatics with 4-6 methyl groups, which is conducive to the aromatics cycle. Accordingly, more propene can be obtained by elevating the Si/Al ratio of SSZ-13. This provides an efficient strategy for CO2 hydrogenation to light olefins with high selectivity.

7.
Angew Chem Int Ed Engl ; 63(10): e202318625, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38231132

RESUMO

An efficient catalytic asymmetric electrophilic sulfenylation reaction for the synthesis of planar-chiral sulfur-containing cyclophanes has been developed for the first time. This was achieved by using a new Lewis base catalyst and a new ortho-trifluoromethyl-substituted sulfenylating reagent. Using the substrates with low rotational energy barrier, the transformation proceeded through a dynamic kinetic resolution, and the high rotational energy barrier of the substrates allowed the reaction to undergo a kinetic resolution process. Meanwhile, this transformation was compatible with a desymmetrization process when the symmetric substrates were used. Various planar-chiral sulfur-containing cyclophanes were readily obtained in moderate to excellent yields with moderate to excellent enantioselectivities (up to 97 % yield and 95 % ee). This approach was used to synthesize pharmaceutically relevant planar-chiral sulfur-containing molecules. Density functional theory calculations showed that π-π interactions between the sulfenyl group and the aromatic ring in the substrate play a crucial role in enantioinduction in this sulfenylation reaction.

8.
Front Oncol ; 13: 1265726, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965476

RESUMO

Objective: Investigate HPV types in cervical specimens, their correlation with p16 expression in lesions, and diagnostic value for cervical lesions. Enhance clinical diagnosis reliability. Methods: Retrospective cross-sectional study at Fujian Maternity and Child Health Hospital's Cervical Disease Center (Jun 2019-Dec 2021). Patients with abnormal cervical screening underwent colposcopy and conization. Pathological diagnosis based on colposcopy, cervical biopsy, ECC, and conization. Analyzed HPV genotyping (18 HR-HPV, 5 LR-HPV) and p16 expression correlation. Statistical analysis used R software. Results: he expression of p16 is significantly associated with the infection of high-risk HPV types, such as 16, 33, 52, and 58, with an increased risk of 1.4 times or higher (OR=1.91, 3.14, 1.40, and 1.78, respectively). The risk of p16 expression increased 4-fold for multiple high-risk HPV types [adjusted OR (95% CI) = 4 (2.92~5.5), P-value <0.001]. Compared to the p16(-) group, the p16(+) group had a higher association with cervical lesions worse than HSIL (High-grade Squamous Intraepithelial Lesions).In the group with multiple Human Papillomavirus Infections with types 16, 33, 52, and 58, the risk of cervical lesions worse than HSIL increased by up to 660-fold compared to the negative group (adjusted OR=660.62, 95% CI: 91.39~4775.53, P<0.001), indicating that this combination of HPV types posed the greatest risk for cervical lesions above HSIL. Conclusions: p16 plays a crucial role in cervical lesion progression, linked to high-risk HPV. Combining p16 with HPV screening improves cervical cancer detection. Studying multiple HPV infections will enhance prevention and management.

9.
Anal Chem ; 95(47): 17372-17383, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37963241

RESUMO

The activable NIR-based phototheranostic nanoplatform (NP) is considered an efficient and reliable tumor treatment due to its strong targeting ability, flexible controllability, minimal side effects, and ideal therapeutic effect. This work describes the rational design of a second near-infrared (NIR-II) fluorescence imaging-guided organic phototheranostic NP (FTEP-TBFc NP). The molecular-engineered phototheranostic NP has a sensitive response to glutathione (GSH), generating hydrogen sulfide (H2S) gas, and delivering ferrocene molecules in the tumor microenvironment (TME). Under 808 nm irradiation, FTEP-TBFc could not only simultaneously generate fluorescence, heat, and singlet oxygen but also greatly enhance the generation of reactive oxygen species to improve chemodynamic therapy (CDT) and photodynamic therapy (PDT) at a biosafe laser power of 0.33 W/cm2. H2S inhibits the activity of catalase and cytochrome c oxidase (COX IV) to cause the enhancement of CDT and hypothermal photothermal therapy (HPTT). Moreover, the decreased intracellular GSH concentration further increases CDT's efficacy and downregulates glutathione peroxidase 4 (GPX4) for the accumulation of lipid hydroperoxides, thus causing the ferroptosis process. Collectively, FTEP-TBFc NPs show great potential as a versatile and efficient NP for specific tumor imaging-guided multimodal cancer therapy. This unique strategy provides new perspectives and methods for designing and applying activable biomedical phototheranostics.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Microambiente Tumoral , Fotoquimioterapia/métodos , Terapia Combinada , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Imagem Óptica , Linhagem Celular Tumoral , Nanomedicina Teranóstica/métodos
10.
Adv Sci (Weinh) ; 10(36): e2304104, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37983599

RESUMO

Tumor microenvironment (TME)-triggered phototheranostic platform offers a feasible strategy to improve cancer diagnosis accuracy and minimize treatment side effects. Developing a stable and biocompatible molecular phototheranostic platform for TME-activated second near-infrared (NIR-II) fluorescence imaging-guided multimodal cascade therapy is a promising strategy for creating desirable anticancer agents. Herein, a new NIR-II fluorescence imaging-guided activatable molecular phototheranostic platform (IR-FEP-RGD-S-S-S-Fc) is presented for actively targeted tumor imaging and hydrogen sulfide (H2 S) gas-enhanced chemodynamic-hypothermal photothermal combined therapy (CDT/HPTT). It is revealed for the first time that the coupling distance between IR-FE and ferrocene is proportional to the photoinduced electron transfer (PET), and the aqueous environment is favorable for PET generation. The part of Cyclic-RGDfK (cRGDfk) peptides can target the tumor and benefit the endocytosis of nanoparticles. The high-concentration glutathione (GSH) in the TME will separate the fluorescence molecule and ferrocene by the GSH-sensitive trisulfide bond, realizing light-up NIR-II fluorescence imaging and a cascade of trimodal synergistic CDT/HPTT/gas therapy (GT). In addition, the accumulation of hydroxyl radicals (•OH) and down-regulation of glutathione peroxidase 4 (GPX4) can produce excessive harmful lipid hydroperoxides, ultimately leading to ferroptosis.


Assuntos
Neoplasias , Terapia Fototérmica , Humanos , Metalocenos , Imagem Óptica , Glutationa , Microambiente Tumoral
11.
Nat Commun ; 14(1): 7873, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036528

RESUMO

As a red tide algal toxin with intense neurotoxicity distributed worldwide, domoic acid (DA) has attracted increasing concerns. In this work, the integrative analysis of metagenome and metabolome are applied to investigate the impact of DA on nitrogen cycling in coastal sediments. Here we show that DA can act as a stressor to induce the variation of nitrogen (N) cycling by altering the abundance of functional genes and electron supply. Moreover, microecology theory revealed that DA can increase the role of deterministic assembly in microbial dynamic succession, resulting in the shift of niches and, ultimately, the alteration in N cycling. Notably, denitrification and Anammox, the important process for sediment N removal, are markedly limited by DA. Also, variation of N cycling implies the modification in cycles of other associated elements. Overall, DA is capable of ecosystem-level effects, which require further evaluation of its potential cascading effects.


Assuntos
Ecossistema , Sedimentos Geológicos , Ciclo do Nitrogênio , Nitrogênio/análise , Desnitrificação
12.
Mar Environ Res ; 191: 106131, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37579703

RESUMO

Domoic acid (DA)-producing algal blooms have been the issue of worldwide concerns in recent decades, but there has never been any attempt to investigate the effects of DA on microbial ecology in marine environments. Protists are considered to be key regulators of microbial activity, community structure and evolution, we therefore explore the effect of DA on the ecology of protists via metagenome in this work. The results indicate that trace amounts of DA can act as a stressor to alter alpha and beta diversity of protistan community. Among trophic functional groups, consumers and phototrophs are negative responders of DA, implying DA is potentially capable of functional-level effects in the ocean. Moreover, microecological theory reveals that induction of DA increases the role of deterministic processes in microbial community assembly, thus altering the biotic relationships and successional processes in symbiotic patterns. Finally, we demonstrate that the mechanism by which DA shapes protistan ecological network is by acting on phototrophs, which triggers cascading effects in networks and eventually leading to shifts in ecological succession of protists. Overall, our results present the first perspective regarding the effects of DA on marine microbial ecology, which will supplement timely information on the ecological impacts of DA in the ocean.


Assuntos
Toxinas Marinhas , Microbiota , Ácido Caínico/toxicidade , Eucariotos
13.
Small ; 19(47): e2304245, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37480178

RESUMO

The robust and scalable oxygen evolution electrocatalysts that can deliver high current densities at low applied potential is a great challenge for the large-scale industrial application in hydrogen production. Here, the preparation of a grain-boundary-rich Ni-Fe (oxy)hydroxide catalyst on Ni foam is reported using a scalable coating approach followed by a chemical precipitating treatment. This facile method effectively assembles the hierarchical Ni-Fe (oxy)hydroxide nanosheet in the ultrasmall crystalline domains (<4 nm) with rich grain boundaries. The hierarchical nanosheet structure with the grain boundaries provides more accessible catalytic sites, facile charge, and mass transfer. Benefiting from the abundant grain boundaries in the hierarchical nanosheets, the as-prepared Ni-Fe (oxy)hydroxide electrodes deliver current densities of 500 and 1000 mA cm-2 at overpotentials of only 278 and 296 mV for the oxygen evolution reaction. The prepared electrode also exhibits long-term durability at a high current density in alkaline conditions.

14.
Biomater Sci ; 11(16): 5674-5679, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37439102

RESUMO

Moderate oxygen (O2) supply and uneven distribution of oxygen at the tumor site usually hinder the therapeutic efficacy of hypoxia-activated prodrugs. In this report, we designed a ferrocene-containing supramolecular nanomedicine (PFC/GOD-TPZ) with the PEG corona and disulfide-bond cross-linked core to co-encapsulate 4-di-N-oxide tirapazamine (TPZ) and glucose oxidase (GOD). The PEG corona of PFC/GOD-TPZ could be weakly acidic tumor pH-responsively detached for an enhanced cellular internalization, while the disulfide-bond cross-linked core could be cleavaged by intracellular glutathione (GSH) to present a GSH-triggered drug-release behavior. Subsequently, the cascade reactions, including catalytic reactions among the released GOD, glucose, and O2 to generate H2O2 and the subsequent Fenton reaction between ferrocene and H2O2, occurred. With the depletion of O2, the non-toxic TPZ was activated and converted into the cytotoxic therapeutic agent benzotriazinyl (BTZ) radical under the exacerbated hypoxic microenvironment. Collectively, the PFC/GOD-TPZ provides a promising strategy for effective combination therapy of GOD-mediated starvation therapy, chemodynamic therapy (CDT), and hypoxia-activated chemotherapy (CT).


Assuntos
Antineoplásicos , Neoplasias , Humanos , Nanomedicina , Metalocenos/farmacologia , Metalocenos/uso terapêutico , Peróxido de Hidrogênio/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Tirapazamina/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Oxigênio , Hipóxia/tratamento farmacológico , Glutationa , Dissulfetos/farmacologia , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral , Microambiente Tumoral
15.
J Am Chem Soc ; 145(30): 16852-16861, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37466142

RESUMO

The inert C(sp3)-H bond and easy overoxidation of toluene make the selective oxidation of toluene to benzaldehyde a great challenge. Herein, we present that a photocatalyst, constructed with a small amount (1 mol %) of amorphous BiOCl nanosheets assembled on TiO2 (denoted as 0.01BOC/TiO2), shows excellent performance in toluene oxidation to benzaldehyde, with 85% selectivity at 10% conversion, and the benzaldehyde formation rate is up to 1.7 mmol g-1 h-1, which is 5.6 and 3.7 times that of bare TiO2 and BOC, respectively. In addition to the charge separation function of the BOC/TiO2 heterojunction, we found that the amorphous structure of BOC endows its abundant surface oxygen vacancies (Ov), which can further promote the charge separation. Most importantly, the surface Ov of amorphous BOC can efficiently adsorb and activate O2, and amorphous BOC makes the product, benzaldehyde, easily desorb from the catalyst surface, which alleviates the further oxidation of benzaldehyde, and results in the high selectivity. This work highlights the importance of the microstructure based on heterojunctions, which is conducive to the rational design of photocatalysts with high performance in organic synthesis.

16.
ACS Appl Mater Interfaces ; 15(19): 23185-23198, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37129564

RESUMO

Effective removal of kinetically inert dilute nitrogen oxide (NO, ppb) without NO2 emission is still a challenging topic in environmental pollution control. One effective approach to reducing the harm of NO is the construction of photocatalysts with diversified microstructures and atomic arrangements that could promote adsorption, activation, and complete removal of NO without yielding secondary pollution. Herein, microstructure regulations of ZnO photocatalysts were attempted by altering the reaction temperature and alkalinity in a unique ionic liquid-based solid-state synthesis and further investigated for the removal of dilute NO upon light irradiation. Microstructure observations indicated that as-tuned photocatalysts displayed unique nucleation, diverse morphologies (spherical nanoparticles, short and long nanorods), defect-related optical characteristics, and enhanced carrier separations. Such defect-related surface-interface aspects, especially Vo″-related defects of ZnO devoted them to the 4.16-fold enhanced NO removal and 2.76 magnitude order decreased NO2 yields, respectively. Improved NO removal and toxic product inhabitation in as-tuned ZnO was disclosed by mechanistic exploitations. It was revealed that regulated microstructures, defect-related charge carrier separation, and strengthened surface interactions were beneficial to active species production and molecular oxygen activation in ZnO, subsequently contributing to the improved NO removal and simultaneous avoidance of NO2 formation. This investigation shed light on the facile regulation of microstructures and the roles of surface chemistry in the oxidation of low concentration NO in the ppb level upon light illumination.

17.
Chem Commun (Camb) ; 59(49): 7607-7610, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37254746

RESUMO

ZnZrO/Mg-Si-ZSM-5 tandem catalysts enable CO2 hydrogenation to para-xylene (PX) with PX selectivity up to 28% and a proportion of PX in xylene up to 84%. SiO2 and MgO modification increases the PX selectivity by reducing the Brønsted acid sites and reducing the pore size of the zeolite.


Assuntos
Dióxido de Carbono , Dióxido de Silício , Xilenos , Hidrogenação
18.
Angew Chem Int Ed Engl ; 62(19): e202301562, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36880801

RESUMO

Identifying electrocatalysts with functions of easy dissociation of water, rapid transformation of hydroxyl and facile hydrogen-hydrogen bond formation are indispensable while challenge for realizing efficient alkaline hydrogen evolution reaction (HER). Herein, we presented the design of Ni3 Sn2 -NiSnOx nanocomposites towards addressing this challenge. We showed that Ni3 Sn2 possessed ideal hydrogen adsorption and low hydroxyl adsorption abilities and NiSnOx facilitated water dissociation and hydroxyl transfer process, respectively. Consequently, the fine-tuned interplay of the two functional parts realized the mutual coordination among the multiple functions and led to significantly boosted HER kinetics. Current densities of 10 and 1000 mA cm-2 were obtained at overpotentials of 14 and 165 mV on the optimized catalyst. This work highlights the significance of considering intrinsic interactions between active sites and all pertinent intermediates on obtaining promising electrocatalysts.

19.
Adv Mater ; 35(19): e2202952, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36871207

RESUMO

Involving eight electron transfer process and multiple intermediates of nitrate (NO3 - ) reduction reaction leads to a sluggish kinetic and low Faradaic efficiency, therefore, it is essential to get an insight into the reaction mechanism to develop highly efficient electrocatalyst. Herein, a series of reduced-graphene-oxide-supported RuCu alloy catalysts (Rux Cux /rGO) are fabricated and used for the direct reduction of NO3 - to NH3 . It is found that the Ru1 Cu10 /rGO shows the ammonia formation rate of 0.38 mmol cm-2 h-1 (loading 1 mg cm-2 ) and the ammonia Faradaic efficiency of 98% under an ultralow potential of -0.05 V versus Reversible Hydrogen Electode (RHE), which is comparable to Ru catalyst. The highly efficient activity of Ru1 Cu10 /rGO can be attributed to the synergetic effect between Ru and Cu sites via a relay catalysis, in which the Cu shows the exclusively efficient activity for the reduction of NO3 - to NO2 - and Ru exhibits the superior activity for NO2 - to NH3 . In addition, the doping of Ru into Cu tunes the d-band center of alloy and effectively modulates the adsorption energy of the NO3 - and NO2 - , which promotes the direct reduction of NO3 - to NH3 . This synergetic electrocatalysis strategy opens a new avenue for developing highly efficient multifunctional catalysts.

20.
Int J Biol Macromol ; 233: 123652, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36780962

RESUMO

Neuropsychiatric diseases are related to early life stress (ELS), patients often have abnormal learning, memory and emotion. But the regulatory mechanism is unclear. Hippocampal synaptic plasticity (HSP) changes are important mechanism. RhoA pathway is known to regulate HSP by modulating of dendritic spines (DS), whether it's involved in HSP changes in ELS hasn't been reported. So we investigated whether and how RhoA participates in HSP regulation in ELS. The ELS model was established by separation-rearing in juvenile. Results of IntelliCage detection etc. showed simple learning and memory wasn't affected, but spatial, punitive learning and memories reduced, the desire to explore novel things reduced, the anxiety-like emotion increased. We further found hippocampus was activated, the hippocampal neurons dendritic complexities reduced, the proportion of mature DS decreased. The full-length transcriptome sequencing techniques was used to screen for differentially expressed genes involved in regulating HSP changes, we found RhoA gene was up-regulated. We detected RhoA protein, RhoA phosphorylation and downstream molecules expression changes, results shown RhoA and p-RhoA, p-ROCK2 expression increased, p-LIMK, p-cofilin expression and F-actin/G-actin ratio decreased. Our study revealed HSP changes in ELS maybe regulate by activation RhoA through ROCK2/LIMK/cofilin pathway regulated F-actin/G-actin balance and DS plasticity, affecting emotion and cognition.


Assuntos
Actinas , Proteína rhoA de Ligação ao GTP , Animais , Ratos , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Cognição , Emoções , Hipocampo/metabolismo , Plasticidade Neuronal , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo
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