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1.
Ecotoxicol Environ Saf ; 276: 116329, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626604

RESUMO

Due to continuous plantation of poplar, its growth and biomass accumulation may be negatively affected by the accumulation of allelochemicals such as para-hydroxybenzoic acid (pHBA) in soil. As photosynthesis is the most fundamental process in plants, it can be negatively impacted by pHBA stress. Therefore, it is crucial to improve photosynthetic capacity under pHBA stress to facilitate poplar plant growth. The mitogen-activated protein kinase (MAPK) cascade pathway is widely involved in environmental stress responses in plants. However, the regulation mechanisms of photosynthesis-related pathways by MAPK pathway genes under pHBA stress are still unclear. In this study, through transcriptome analysis and weighted gene co-expression network analysis, we observed that PeMPK7 overexpression in poplar can regulate the expression of photosynthesis-related genes and transcription factor genes, namely, WRKY1, WRKY33, and ERF3, during the early stage of pHBA stress. In addition, PeMPK7 can improve photosynthesis in poplar under long-term pHBA stress. Moreover, yeast two-hybrid and pull-down assays confirmed the interaction between PeMPK7 and PeMKK7/10. Based on these results, a schematic diagram of the pathways involved in the regulation of photosynthesis by PeMPK7 was constructed. This study provided novel insights into the molecular mechanisms of regulation of pHBA stress via MAPK cascade pathway.

2.
Talanta ; 272: 125839, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38428134

RESUMO

A nitrogen-doped carbon shell loaded with a gold and silver alloy (Au/Ag@NCS) was constructed for highly sensitive electrochemical detection of NO. The Au/Ag@NCS material was prepared by use of SiO2 particles as a template to polymerize imidazolium-based ionic liquids loaded with gold and silver salts, and subsequent carbonization treatment and template removal. The hollow structure of the carbon material acted as a carrier for electrochemical sensing, offering high specific surface area, large pore capacity, robust electron conductivity, and excellent mechanical stability. The inclusion of gold in the composite enhanced its catalytic and sensing capabilities, while silver oxidation was employed as a reference signal for accurate detection. By utilization of the Au/Ag@NCS-modified electrode, a wide detection range from 0.5 nM to 1.05 µM with a low detection limit of 0.32 nM was achieved for NO detection. The electrochemical sensor also exhibited high selectivity and excellent stability. The fabricated sensor was further utilized to explore the release of NO from breast cancer cells, revealing that the electrochemical platform could be regarded as an important method to study the daily tests of NO in clinical application.

3.
J Neurosci ; 44(12)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38418221

RESUMO

As the most common form of dementia in the world, Alzheimer's disease (AD) is a progressive neurological disorder marked by cognitive and behavioral impairment. According to previous researches, abundant social connections shield against dementia. However, it is still unclear how exactly social interactions benefit cognitive abilities in people with AD and how this process is used to increase their general cognitive performance. In this study, we found that single novel social (SNS) stimulation promoted c-Fos expression and increased the protein levels of mature ADAM10/17 and sAPPα in the ventral hippocampus (vHPC) of wild-type (WT) mice, which are hippocampal dorsal CA2 (dCA2) neuron activity and vHPC NMDAR dependent. Additionally, we discovered that SNS caused similar changes in an AD model, FAD4T mice, and these alterations could be reversed by α-secretase inhibitor. Furthermore, we also found that multiple novel social (MNS) stimulation improved synaptic plasticity and memory impairments in both male and female FAD4T mice, accompanied by α-secretase activation and Aß reduction. These findings provide insight into the process underpinning how social interaction helps AD patients who are experiencing cognitive decline, and we also imply that novel social interaction and activation of the α-secretase may be preventative and therapeutic in the early stages of AD.


Assuntos
Doença de Alzheimer , Humanos , Masculino , Camundongos , Feminino , Animais , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Camundongos Transgênicos , Transtornos da Memória/metabolismo , Hipocampo/metabolismo , Peptídeos beta-Amiloides/metabolismo , Modelos Animais de Doenças
4.
Food Chem ; 441: 138388, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38219368

RESUMO

Streptococcus pyogenes (GAS) is one of the most virulent and infectious bacteria, severely threatening health and lives of people worldwide. Honey has been proven to have effective capability against GAS, but the underlying metabolites and mechanisms are still unclear. In this study, the Castanopsis honey (CH) showed significant antibacterial ability compared to other seven kinds of honey and artificial honey. Furthermore, the antibacterial metabolites and their targets in CH were screened by combined method of metabolomics, network pharmacology, and molecular docking. The results suggested that the activities of two antioxidant enzymes, glutathione peroxidase and tyrosyl tRNA synthetase identified as the primary targets, were significantly inhibited by CH, which significantly increased the level of oxidative stress in GAS. The results revealed a possibly novel mechanism regulating the oxidative stress and inhibits the growth in bacteria, providing strong experimental evidence to support the further development of CH as a novel antibacterial agent.


Assuntos
Mel , Streptococcus pyogenes , Humanos , Farmacologia em Rede , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , Metabolômica
5.
Adv Mater ; 36(15): e2309534, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38199243

RESUMO

Photodynamic therapy (PDT) depends on the light-irradiated exciting of photosensitizer (PS) to generate reactive oxygen species (ROS), which faces challenges and limitations in hypoxia and antioxidant response of cancer cells, and limited tissue-penetration of light. Herein, a multifunctional DNA/upconversion nanoparticles (UCNPs) complex is developed which enables controlled co-delivery of CRISPR-Cas9, hemin, and protoporphyrin (PP) for synergistic PDT. An ultralong single-stranded DNA (ssDNA) is prepared via rolling circle amplification (RCA), which contains recognition sequences of single guide RNA (sgRNA) for loading Cas9 ribonucleoprotein (RNP), G-quadruplex sequences for loading hemin and PP, and linker sequences for combining UCNP. Cas9 RNP cleaves the antioxidant regulator nuclear factor E2-related factor 2 (Nrf2), improving the sensitivity of cancer cells to ROS, and enhancing the synergistic PDT effect. The G-quadruplex/hemin DNAzyme mimicks horseradish peroxidase (HRP) to catalyze the endogenous H2O2 to O2, overcoming hypoxia condition in tumors. The introduced UCNP converts NIR irradiation with deep tissue penetration to light with shorter wavelength, exciting PP to transform the abundant O2 to 1O2. The integration of gene editing and PDT allows substantial accumulation of 1O2 in cancer cells for enhanced cell apoptosis, and this synergistic PDT has shown remarkable therapeutic efficacy in a breast cancer mouse model.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Camundongos , Animais , Sistemas CRISPR-Cas , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes , Hemina , Peróxido de Hidrogênio , RNA Guia de Sistemas CRISPR-Cas , Nanopartículas/uso terapêutico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Hipóxia , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico
6.
Clin Kidney J ; 16(12): 2567-2577, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38046021

RESUMO

Background: Few studies have evaluated the treatment of immunoglobulin A nephropathy (IgAN) patients with nephrotic syndrome (NS) and mesangioproliferative glomerulonephritis (MPGN). The aim of this study was to compare the therapeutic effects of oral glucocorticoids (GCS) combined with intravenous cyclophosphamide (CTX) and oral GCS alone in the treatment of the MPGN-IgAN patients with NS. Methods: Biopsy-proven primary IgAN patients who were aged ≥14 years at diagnosis, had coexistent NS and MPGN and estimated glomerular filtration rate (eGFR) ≥15 mL/min/1.73 m2, and were treated by oral GCS combined with intravenous CTX or oral GCS alone for 6-12 months were retrospectively included. The patients in the GCS + CTX (prednisone 0.6-0.8 mg/kg/day and intravenous CTX 0.6-1.0 g monthly) or GCS (prednisone 0.8-1 mg/kg/day) group were rather matched at a 1:1 ratio on key characteristics by propensity score matching. The primary outcome was defined as either complete remission or partial remission at Month 24. The secondary outcome was a composite renal endpoint defined as a 50% decline in eGFR, doubling of serum creatinine or progression to end-stage kidney disease. Results: Among the 146 IgAN patients who met the inclusion criteria, 42 patients were enrolled in the GCS + CTX group, and 42 patients were enrolled in the GCS group after propensity score matching. The clinical and histological parameters were similar between the two groups. Remission occurred more frequently in the GCS + CTX group at Month 6 (88.1% vs 52.4%, P < 0.001), Month 12 (88.1% vs 56.1%, P = 0.001) and Month 24 (85.0% vs 47.5%, P < 0.001) than in the GCS group. Moreover, subgroup analysis revealed that the higher response rate at Month 24 in the GCS + CTX group than in the GCS group was also present in different subgroups defined by sex, age, eGFR or Oxford MEST-C. Notably, we found that eGFR decreased at a lower rate in patients from the GCS + CTX group than in patients from the GCS group [eGFR slope: 0.05(-3.09, 3.67) vs -2.56 (-11.30, 0.86) mL/min/1.73 m2/year, P = 0.03]. Based on multivariate Cox regression analysis, GCS + CTX treatment was found to be independently associated with a decrease in risk for the composite endpoint after adjusted by the International Risk Prediction Score with race (hazard ratio = 0.17, 95% confidence interval 0.04-0.83, P = .03). There was no significant difference in adverse events (50.0% vs 42.9%, P = 0.51) or serious adverse events (7.1% vs 11.9%, P = .71) between the two groups. Conclusions: Oral GCS combined with intravenous CTX is superior to GCS alone in treating MPGN-IgAN patients combined with NS. As the retrospective design and small sample size, our findings need to be validated by a prospective study.

7.
Psychol Health Med ; : 1-14, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053313

RESUMO

This study aimed to identify group variations in adolescent impulsivity and explore the connections between latent categories of impulsivity and psychological symptoms, social anxiety, and internet addiction. The research involved 2,378 participants from three middle schools in Guangdong Province, China. We assessed the impact of impulsivity levels (measured by BBIS) on depression (measured by KADS-11), anxiety (measured by SCARED), social anxiety (measured by SASC), and internet addiction (measured by YDQ). Latent profile analysis was employed to examine the diversity in adolescent impulsivity, establish latent classifications, and investigate the variances in psychological symptoms, social anxiety, and internet addiction. The middle school students were categorized into five latent groups based on their BBIS scores. Statistical analysis revealed five impulsivity categories, strongly linked to psychological symptoms and social anxiety but less strongly associated with internet addiction. The high impulsivity group (C5) exhibited higher scores in psychological symptoms and social anxiety compared to other groups, whereas the poor self-regulation group (C3) displayed greater psychological symptoms, social anxiety scores, and internet addiction than the impulsive behavior group (C4). Future investigations should investigate the underlying factors contributing to the observed differences among these groups.

8.
IEEE Trans Image Process ; 32: 6020-6031, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37910424

RESUMO

In this paper, we present the first attempt at determining where the achievable rate-distortion (R-D) performance bound in versatile video coding (VVC) intra coding is when considering the mutual dependency in the rate-distortion optimization (RDO) process. In particular, the abundant search space of encoding parameters in VVC intra coding is practically explored with a beam search-based joint rate-distortion optimization (BSJRDO) scheme. As such, the partitioning, prediction and transform decisions are jointly optimized across different coding units (CUs) with a customized search subset instead of the full space. To make the beam search process implementation-friendly for VVC, the dependencies among the CUs are truncated at different depths. To facilitate finer computational scalability, the beam size is flexibly adjusted based on the characteristics of the CUs, such that the operational points that satisfy different complexity demands for diverse applications can be practically obtained. The proposed BSJRDO approach, which fully conforms to the VVC decoding syntax, can serve as both the way toward the optimal RDO bound and a practical performance-boosting solution. BSJRDO is further implemented on a VVC coding platform (VVC Test model (VTM) 12.0), and extensive experiments show that BSJRDO can achieve 1.30% and 3.22% bit rate savings compared to the VTM anchor under the common test condition and low-bit-rate coding scenarios, respectively. Moreover, the performance gain can also be flexibly customized with different computational overheads.

9.
Vet Sci ; 10(8)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37624272

RESUMO

Strengthening the analysis and risk assessment of the pig epidemic will help to better prevent and mitigate epidemic risks and promote the high-quality development of the pig industry. Based on a systematic understanding of live pig epidemics, a risk assessment index system was constructed, and the spatial and temporal variation characteristics of pig epidemics in China were explored by the entropy method. In recent years, the overall trend in pig epidemics over time first increased and then decreased; in space, the acceleration of the spread of epidemics across the country weakened. China still faces challenges, including many types and a wide range of diseases, large total livestock breeding and weak epidemic prevention and control capacity, and a large risk of introduced foreign animal epidemics. The spatial and temporal variations in the pig epidemic risk were obvious; one high-risk area, two medium-high-risk areas and 10 medium-risk areas have been found in recent years, during which time, the epidemic risk was highest in Beijing, Hainan, Liaoning, Tibet and Zhejiang. However, there were significant differences in the regional distribution of the risk level of pig epidemics in different years. To further build a secure "defense system" for the high-quality development of the pig industry, it is recommended to improve the monitoring and early warning system of pig epidemic risk, perfect the pig epidemic prevention and control system, and strengthen the regional collaboration mechanism of epidemic prevention and control.

10.
Angew Chem Int Ed Engl ; 62(32): e202305536, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37278518

RESUMO

The trans-cleavage property of CRISPR-Cas12a system makes it an excellent tool for disease diagnosis. Nevertheless, most methods based on CRISPR-Cas system still require pre-amplification of the target to achieve the desired detection sensitivity. Here we generate Framework-Hotspot reporters (FHRs) with different local densities to investigate their effect on trans-cleavage activity of Cas12a. We find that the cleavage efficiency increases and the cleavage rate accelerates with increasing reporter density. We further construct a modular sensing platform with CRISPR-Cas12a-based target recognition and FHR-based signal transduction. Encouragingly, this modular platform enables sensitive (100 fM) and rapid (<15 min) detection of pathogen nucleic acids without pre-amplification, as well as detection of tumor protein markers in clinical samples. The design provides a facile strategy for enhanced trans cleavage of Cas12a, which accelerates and broadens its applications in biosensing.


Assuntos
Técnicas Biossensoriais , Ácidos Nucleicos , Sistemas CRISPR-Cas/genética , Biomarcadores Tumorais , Transdução de Sinais
12.
Ecotoxicol Environ Saf ; 262: 115167, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37354565

RESUMO

Mitogen-activated protein kinase (MAPK) plays a crucial role in plant stress response. Poplar is one of the most important afforestation and timber species and inevitably encounters allelopathy effects during continuous cropping. para-hydroxybenzoic acid (pHBA) is a primary soil allelochemical, which can restrict the growth and biomass of poplar. However, the involvement of MAPKs in the underlying physiological and molecular regulatory mechanisms in response to pHBA stress remains unclear. In this study, PeMPK17, a gene encoding a group D MAPK, was cloned from Populus × euramericana. PeMPK17 protein was localized in both nucleus and plasma membrane. Quantitative real-time polymerase chain reaction analysis demonstrated that PeMPK17 expression in poplar increased when treated with pHBA, PEG, and H2O2. Exogenous pHBA and H2O2 induced PeMPK17 expression mediated by reactive oxygen species (ROS). The transgenic poplar plants overexpressing PeMPK17 demonstrated attenuated phenotypic injury, higher relative water content in leaves, and lower ion leakage under pHBA stress. In transgenic poplar, the activity and expression of antioxidant enzymes including superoxide dismutase, peroxidase, and catalase increased, while the content of H2O2, O2·-, and malondialdehyde decreased. These results suggested that PeMPK17 protects cell membranes from oxidative damage by removing excess ROS. In addition, overexpression of PeMPK17 promoted osmoprotectant accumulation including soluble sugar and free proline, which may aid in the regulation of ROS balance under pHBA treatment. Furthermore, the interaction between PeMPK17 and PeMKK7 was confirmed. Collectively, these data identify the molecular mechanisms and signal pathways associated with PeMPK17 that regulate pHBA response in poplar.

13.
Nano Res ; : 1-14, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-37359078

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems are becoming powerful tools for disease biomarkers detection. Due to the specific recognition, cis-cleavage and nonspecific trans-cleavage capabilities, CRISPR/Cas systems have implemented the detection of nucleic acid targets (DNA and RNA) as well as non-nucleic acid targets (e.g., proteins, exosomes, cells, and small molecules). In this review, we first summarize the principles and characteristics of various CRISPR/Cas systems, including CRISPR/Cas9, Cas12, Cas13 and Cas14 systems. Then, various types of applications of CRISPR/Cas systems used in detecting nucleic and non-nucleic acid targets are introduced emphatically. Finally, the prospects and challenges of their applications in biosensing are discussed.

14.
Foods ; 12(11)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37297512

RESUMO

In this study, naked oat bran albumin hydrolysates (NOBAH) were subjected to gel chromatography with Sephadex G-15, reverse phase-high liquid performance separation, and UPLC-ESI-MS/MS identification. Six safe peptides including Gly-Thr-Thr-Gly-Gly-Met-Gly-Thr (GTTGGMGT), Gln-Tyr-Val-Pro-Phe (QYVPF), Gly-Ala-Ala-Ala-Ala-Leu-Val (GAAAALV), Gly-Tyr-His-Gly-His (GYHGH), Gly-Leu-Arg-Ala-Ala-Ala-Ala-Ala-Ala-Glu-Gly-Gly (GLRAAAAAAEGG), and Pro-Ser-Ser-Pro-Pro-Ser (PSSPPS) were identified. Next, in silico screening demonstrated that QYVPF and GYHGH had both angiotensin-I-converting enzyme (ACE) inhibition activity (IC50: 243.36 and 321.94 µmol/L, respectively) and Zinc-chelating ability (14.85 and 0.32 mg/g, respectively). The inhibition kinetics demonstrated that QYVPF and GYHGH were both uncompetitive inhibitors of ACE. Molecular docking showed that QYVPF and GYHGH could bind, respectively, three and five active residues of ACE with short hydrogen bonds (but not belonging to any central pocket). QYVPF and GYHGH could bind, respectively, twenty-two and eleven residues through hydrophobic interactions. Moreover, GYHGH was able to affect zinc tetrahedral coordination in ACE by interacting with His383. The inhibition activities of QYVPF and GYHGH toward ACE were relatively resistant to gastrointestinal digestion. GYHGH improved zinc solubility in the intestines (p > 0.05) because its amino and carboxyl groups were chelating sites for zinc ions. These results suggest the potential applications of naked oat peptides for potential antihypertension or zinc fortification.

15.
Plant Foods Hum Nutr ; 78(2): 419-425, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37300747

RESUMO

To obtain Angiotensin-I-Converting Enzyme (ACE) inhibition peptides with Zn-chelating capacity, quinoa bran glutelin-2 hydrolysates (QBGH) by Flavourzyme and Papain were subjected to Sephadex G-15 gel chromatography, reverse phase-high liquid performance chromatography and UPLC-ESI-MS/MS analysis. Four oligopeptides including GGGSGH, EAGAE, AGGGAGGG and AVPKPS were identified. Of these, only the hexapeptide AVPKPS had both ACE-inhibitory activity (IC50: 123.13 µmol/L) and Zn-chelating ability (17.36 mg/g). Molecular docking showed AVPKPS could bind with active residues Glu384 and Ala354 (both belong to the central S1 pocket of ACE including) through short hydrogen bond and hydrophobic interactions, respectively. Inhibition kinetics verified that AVPKPS was a competitive inhibitor of ACE. Moreover, AVPKPS can affect the zinc tetrahedral coordination in ACE through binding with residues His387 and His383. Fourier-transform infrared spectroscopy analysis demonstrated that the amino and carboxyl groups of AVPKPS were the main chelating sites for zinc ions. Under the gastrointestinal digestion, the ACE inhibition capacity of AVPKPS was relatively stable, and the zinc solubility of AVPKPS-zinc complexes was more stable than zinc sulfate (p < 0.05). These results suggest that quinoa peptides have potential applications as ingredients for antihypertension or zinc fortification.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Chenopodium quinoa , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Glutens , Simulação de Acoplamento Molecular , Espectrometria de Massas em Tandem/métodos , Peptidil Dipeptidase A/metabolismo , Zinco , Peptídeos/farmacologia , Hidrolisados de Proteína/química
16.
Ecotoxicol Environ Saf ; 259: 115033, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37224778

RESUMO

Poplar is widely planted as an economic and ecological tree species. However, accumulation of the phenolic acid allelochemical para-hydroxybenzoic acid (pHBA) in soil is a severe threat to the growth and productivity of poplar. pHBA stress leads to excessive production of reactive oxygen species (ROS). However, it is unclear which redox-sensitive proteins are involved in the pHBA-induced cellular homeostasis regulatory mechanism. We here identified reversible redox-modified proteins and modified cysteine (Cys) sites in exogenous pHBA- and hydrogen peroxide (H2O2)-treated poplar seedling leaves by using the iodoacetyl tandem mass tag-labeled redox proteomics method. In total, 4786 redox modification sites were identified in 3176 proteins, with 104 and 91 proteins being differentially modified at 118 and 101 Cys sites in response to pHBA and H2O2 stresses, respectively. The differentially modified proteins (DMPs) were predicted to be mainly localized in the chloroplast and cytoplasm, with most proteins being enzymes with catalytic activities. The KEGG enrichment analysis of these DMPs revealed that proteins related to the MAPK signaling pathway, soluble sugar metabolism, amino acid metabolism, photosynthesis, and phagosome pathways were extensively regulated by redox modifications. Moreover, combined with our previous quantitative proteomics data, 8 proteins were upregulated and oxidized under both pHBA and H2O2 stresses. Reversible oxidation of Cys sites in these proteins might be actively responsible for the regulation of tolerance to pHBA-induced oxidative stress. Based on the aforementioned results, a redox regulatory model activated by pHBA- and H2O2-induced oxidative stress was proposed. This study conducts the first redox proteomics analysis of poplar in response to pHBA stress and provides a new insight into the mechanistic framework of reversible oxidative post-translational modifications to gain a better understanding of pHBA-induced chemosensory effects on poplar.


Assuntos
Peróxido de Hidrogênio , Proteômica , Peróxido de Hidrogênio/metabolismo , Proteômica/métodos , Parabenos , Cisteína/metabolismo , Estresse Oxidativo , Processamento de Proteína Pós-Traducional , Oxirredução
17.
Nature ; 614(7946): 70-74, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36725993

RESUMO

Strongly interacting spins underlie many intriguing phenomena and applications1-4 ranging from magnetism to quantum information processing. Interacting spins combined with motion show exotic spin transport phenomena, such as superfluidity arising from pairing of spins induced by spin attraction5,6. To understand these complex phenomena, an interacting spin system with high controllability is desired. Quantum spin dynamics have been studied on different platforms with varying capabilities7-13. Here we demonstrate tunable itinerant spin dynamics enabled by dipolar interactions using a gas of potassium-rubidium molecules confined to two-dimensional planes, where a spin-1/2 system is encoded into the molecular rotational levels. The dipolar interaction gives rise to a shift of the rotational transition frequency and a collision-limited Ramsey contrast decay that emerges from the coupled spin and motion. Both the Ising and spin-exchange interactions are precisely tuned by varying the strength and orientation of an electric field, as well as the internal molecular state. This full tunability enables both static and dynamical control of the spin Hamiltonian, allowing reversal of the coherent spin dynamics. Our work establishes an interacting spin platform that allows for exploration of many-body spin dynamics and spin-motion physics using the strong, tunable dipolar interaction.

18.
Chem Rec ; 23(4): e202300013, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36806446

RESUMO

Ru-based materials hold great promise for substituting Pt as potential electrocatalysts toward water electrolysis. Significant progress is made in the fabrication of advanced Ru-based electrocatalysts, but an in-depth understanding of the engineering methods and induced effects is still in their early stage. Herein, we organize a review that focusing on the engineering strategies toward the substantial improvement in electrocatalytic OER and HER performance of Ru-based catalysts, including geometric structure, interface, phase, electronic structure, size, and multicomponent engineering. Subsequently, the induced enhancement in catalytic performance by these engineering strategies are also elucidated. Furthermore, some representative Ru-based electrocatalysts for the electrocatalytic HER and OER applications are also well presented. Finally, the challenges and prospects are also elaborated for the future synthesis of more effective Ru-based catalysts and boost their future application.

19.
Nanoscale Horiz ; 8(4): 441-452, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36762488

RESUMO

The formation of a built-in electric field (BIEF) can induce electron-rich and electron-poor counterparts to synergistically modify electronic configurations and optimize the binding strengths with intermediates, thereby leading to outstanding electrocatalytic performance. Herein, a critical review regarding the concept, modulation strategies, and applications of BIEFs is comprehensively summarized, which begins with the fundamental concepts, together with the advantages of BIEF for boosting electrocatalytic reactions. Then, a systematic summary of the advanced strategies for the modulation of BIEF along with the in-detail mechanisms in its formation are also added. Finally, the applications of BIEF in driving electrocatalytic reactions and some cascade systems for illustrating the conclusive role from the induced BIEF are also systematically discussed, followed by perspectives on the future deployment and opportunity of the BIEF design.

20.
Carbohydr Polym ; 307: 120627, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36781278

RESUMO

Starch is regarded as one of the most promising sustainable materials due to its abundant yield and excellent biodegradability. From the perspective of practical engineering applications, this paper systematically describes the development of starch-based bio-composites in the past decade. Packaging properties, processing characteristics, and current challenges for the efficient processing of starch-based bio-composites are reviewed in industrial packaging. Green coatings, binders, adsorbents, flocculants, flame retardants, and emulsifiers are used as examples to illustrate the versatility of starch-based bio-composites in chemical agent applications. In addition, the work compares the application of starch-based bio-composites in conventional spinning with emerging spinning technologies and describes the challenges of electrostatic spinning for preparing nanoscale starch-based fibers. In terms of flexible electronics, the starch-based bio-composites are regard as a solid polymer electrolyte and easily modified porous material. Moreover, we describe the applications of the starch-based gels in tissue engineering, controlled drug release, and medical dressings. Finally, the theoretical input and technical guidance in the advanced sustainable engineering application of the starch-based bio-composites are provided in the work.


Assuntos
Polímeros , Amido , Amido/química , Engenharia Tecidual
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