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1.
Heliyon ; 10(12): e32404, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975165

RESUMO

To ensure secure and flexible data sharing in cloud storage, attribute-based encryption (ABE) is introduced to meet the requirements of fine-grained access control and secure one-to-many data sharing. However, the computational burden imposed by attribute encryption renders it unsuitable for resource-constrained environments such as the Internet of Things (IoT) and edge computing. Furthermore, the issue of accountability for illegal keys is crucial, as authorized users may actively disclose or sell authorization keys for personal gain, and keys may also passively leak due to management negligence or hacking incidents. Additionally, since all authorization keys are generated by the attribute authorization center, there is a potential risk of unauthorized key forgery. In response to these challenges, this paper proposes an efficient and accountable leakage-resistant scheme based on attribute encryption. The scheme adopts more secure online/offline encryption mechanisms and cloud server-assisted decryption to alleviate the computational burden on resource-constrained devices. For illegal keys, the scheme supports accountability for both users and the authorization center, allowing the revocation of decryption privileges for malicious users. In the case of passively leaked keys, timely key updates and revocation of decryption capabilities for leaked keys are implemented. Finally, the paper provides selective security and accountability proofs for the scheme under standard models. Efficiency analysis and experimental results demonstrate that the proposed scheme enhances encryption/decryption efficiency, and the storage overhead for accountability is also extremely low.

2.
J Craniofac Surg ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953580

RESUMO

Condylar is one of the most vulnerable sites to be traumatized in pediatric mandible fracture, while temporomandibular joint ankylosis might be the most severe complication of condylar fracture in children. There exists a long-time controversy on the treatment of condylar fractures in children. Considering the risk of facial nerve injury and a certain probability of absorption or even ankylosis after open reduction and internal fixation (ORIF) of condylar fractures, a series of nonsurgical approaches are preferred in cases without severe malocclusion or shortening of the ramus. Our treatment plan was carried out through combining procedures of Botulinum toxin A injection in lateral pterygoid muscle with ORIF of para symphyseal fracture; subsequently, a conservative way of the occlusal splint with elastic traction was performed. Three patients of bilateral or unilateral condylar fractures, aged between 2 y and 6 y, were involved in this treatment. After more than 1 year's follow-up, the occlusion was satisfactory in all patients. Condylar remodeling was approximately complete in 3 months, and no unwanted complications were observed. We may expect this method to offer a new idea when dealing with children's condylar fracture.

3.
BMC Plant Biol ; 24(1): 626, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961401

RESUMO

BACKGROUND: The calmodulin (CaM) and calmodulin-like (CML) proteins play regulatory roles in plant growth and development, responses to biotic and abiotic stresses, and other biological processes. As a popular fruit and ornamental crop, it is important to explore the regulatory mechanism of flower and fruit development of passion fruit. RESULTS: In this study, 32 PeCaM/PeCML genes were identified from passion fruit genome and were divided into 9 groups based on phylogenetic analysis. The structural analysis, including conserved motifs, gene structure and homologous modeling, illustrates that the PeCaM/PeCML in the same subgroup have relative conserved structural features. Collinearity analysis suggested that the expansion of the CaM/CML gene family likely took place mainly by segmental duplication, and the whole genome replication events were closely related with the rapid expansion of the gene group. PeCaM/PeCMLs were potentially required for different floral tissues development. Significantly, PeCML26 had extremely high expression levels during ovule and fruit development compared with other PeCML genes, suggesting that PeCML26 had potential functions involved in the development of passion fruit flowers and fruits. The co-presence of various cis-elements associated with growth and development, hormone responsiveness, and stress responsiveness in the promoter regions of these PeCaM/PeCMLs might contribute to their diverse regulatory roles. Furthermore, PeCaM/PeCMLs were also induced by various abiotic stresses. This work provides a comprehensive understanding of the CaM/CML gene family and valuable clues for future studies on the function and evolution of CaM/CML genes in passion fruit. CONCLUSION: A total of 32 PeCaM/PeCML genes were divided into 9 groups. The PeCaM/PeCML genes showed differential expression patterns in floral tissues at different development stages. It is worth noting that PeCML26, which is highly homologous to AtCaM2, not only interacts with multiple BBR-BPC TFs, but also has high expression levels during ovule and fruit development, suggesting that PeCML26 had potential functions involved in the development of passion fruit flowers and fruits. This research lays the foundation for future investigations and validation of the potential function of PeCaM/PeCML genes in the growth and development of passion fruit.


Assuntos
Calmodulina , Flores , Frutas , Passiflora , Filogenia , Proteínas de Plantas , Passiflora/genética , Passiflora/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Calmodulina/genética , Calmodulina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Genes de Plantas , Perfilação da Expressão Gênica
4.
J Hazard Mater ; 476: 135112, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38981234

RESUMO

In light of the significant risks that mycotoxins posed to public health and environmental safety, this research developed an adsorbent MIPs/Apt/AuNPs@ZIF-67 (MA-AZ) utilizing a dual-recognition approach combining molecularly imprinted polymers (MIPs) and aptamer (Apt). This innovative method enabled the effective and highly selective recognition and enrichment of ochratoxin A (OTA). ZIF-67 was utilized as a carrier with a substantial specific surface area, and gold nanoparticles (AuNPs) were loaded on its surface to fix the thiol-modified Apt on the surface of the carrier. Then, an initiator was used to initiate a polymerization reaction, and the generated MIPs coated Apt/AuNPs@ZIF-67, thereby synthesizing the MA-AZ with a "synergistic recognition" effect. The Apt significantly increased the number of recognition sites within the imprinted cavities, and MIPs played roles in identifying targets, fixing and protecting Apt. The combination of the both produced the effect of "1+1>2". The study on the adsorption performance of MA-AZ found that the adsorption capacity of MA-AZ could reach 65.1 mg/g, and the imprinted factor was 5.48. In addition, MA-AZ exhibited excellent stability, specificity, reusability and recovery rate. Thus, this study offers valuable insights for the recognition and enrichment of hazardous substances, and helps to promote the rapid development of safety detection.

6.
Front Plant Sci ; 15: 1387102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38916037

RESUMO

Sesuvium portulacastrum L. is a flowering succulent halophyte in the ice plant family Aizoaceae. There are various ecotypes distributed in sandy coastlines and salty marshlands in tropical and subtropical regions with the common name of sea purslane. These plants are tolerant to salt, drought, and flooding stresses and have been used for the stabilization of sand dunes and the restoration of coastal areas. With the increased salinization of agricultural soils and the widespread pollution of toxic metals in the environment, as well as excessive nutrients in waterbodies, S. portulacastrum has been explored for the desalination of saline soils and the phytoremediation of metals from contaminated soils and nitrogen and phosphorus from eutrophic water. In addition, sea purslane has nutraceutical and pharmaceutical value. Tissue analysis indicates that many ecotypes are rich in carbohydrates, proteins, vitamins, and mineral nutrients. Native Americans in Florida eat it raw, pickled, or cooked. In the Philippines, it is known as atchara after being pickled. S. portulacastrum contains high levels of ecdysteroids, which possess antidiabetic, anticancer, and anti-inflammatory activities in mammals. In this review article, we present the botanical information, the physiological and molecular mechanisms underlying the tolerance of sea purslane to different stresses, its nutritional and pharmaceutical value, and the methods for its propagation and production in saline soils and waterbodies. Its adaptability to a wide range of stressful environments and its role in the production of valuable bioactive compounds suggest that S. portulacastrum can be produced in saline soils as a leafy vegetable and is a valuable genetic resource that can be used for the bioremediation of soil salinity and eutrophic water.

7.
Sci Rep ; 14(1): 13622, 2024 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871763

RESUMO

Cardiovascular disease (CVD) and depression are common diseases that lead to adverse health outcomes. Depressive Symptoms may be a risk factor for CVD. But few studies focused on the impact of socioeconomic factors, common medical history and dietary intake about this association. This study analyzed National Health and Nutrition Examination Survey (NHANES) 2007-2016. Complex sampling-weighted logistic regression models were used to compare the odds ratios (ORs) of CVD in participants with different depressive symptoms. 11,516 NHANES participants aged ≥ 40 years were included in the final analysis, of whom 1842 had CVD. Compared with participants with no/minimal depression, participants with mild, moderate, and moderately severe/severe depression had OR values of 1.25 (95%  CI 1.01-1.54), 1.98 (95% CI 1.32-2.96), and 2.41 (95% CI 1.63-3.57). The association of depressive symptoms with CVD follow a dose-dependent pattern. The interactions of depressive symptoms with gender (Interaction P = 0.009), diabetes (Interaction P = 0.010), household income level (Interaction P = 0.002), dietary cholesterol intake (Interaction P = 0.017) on CVD were observed. More severe depressive symptoms are associated with increased risk of CVD in US population. The association may be more pronounced in the female population, population with diabetes, low family income level, or high dietary cholesterol intake.


Assuntos
Doenças Cardiovasculares , Depressão , Inquéritos Nutricionais , Humanos , Masculino , Feminino , Doenças Cardiovasculares/epidemiologia , Depressão/epidemiologia , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Adulto , Idoso , Fatores de Risco , Fatores Socioeconômicos , Razão de Chances
8.
CNS Neurosci Ther ; 30(6): e14792, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38867393

RESUMO

AIMS: Parkinson's disease (PD) patients experience improvement in motor symptoms after deep brain stimulation (DBS) and before initiating stimulation. This is called the microlesion effect. However, the mechanism remains unclear. The study aims to comprehensively explore the changes in functional connectivity (FC) patterns in movement-related brain regions in PD patients during the microlesion phase through seed-based FC analysis. METHODS: The study collected the resting functional magnetic resonance imaging data of 49 PD patients before and after DBS surgery (off stimulation). The cortical and subcortical areas related to motor function were selected for seed-based FC analysis. Meanwhile, their relationship with the motor scale was investigated. RESULTS: The motor-related brain regions were selected as the seed point, and we observed various FC declines within the motor network brain regions. These declines were primarily in the left middle temporal gyrus, bilateral middle frontal gyrus, right supplementary motor area, left precentral gyrus, left postcentral gyrus, left inferior frontal gyrus, and right superior frontal gyrus after DBS. CONCLUSION: The movement-related network was extensively reorganized during the microlesion period. The study provided new information on enhancing motor function from the network level post-DBS.


Assuntos
Estimulação Encefálica Profunda , Imageamento por Ressonância Magnética , Doença de Parkinson , Humanos , Estimulação Encefálica Profunda/métodos , Doença de Parkinson/terapia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Córtex Motor/fisiopatologia , Córtex Motor/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia
9.
Clin Cardiol ; 47(6): e24301, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38895772

RESUMO

BACKGROUND: Statins are lipid-lowering drugs with favorable anti-inflammatory effects. This study aimed to explore different statin-based lipid-lowering strategies to reduce high-sensitivity C-reactive protein (hs-CRP). HYPOTHESIS: The hypothesis is that different statin-based lipid-lowering strategies might reduce hs-CRP. METHODS: This retrospective study included 3653 patients who underwent percutaneous coronary intervention (PCI). Three statin-based lipid-lowering strategies were investigated, including different types of statins (atorvastatin vs. rosuvastatin), statin combined with ezetimibe therapy (vs. without), and intensive statin therapy (vs. regular). The hs-CRP levels and blood lipid indicators were measured at baseline and after 1-month lipid-lowering therapy. Multivariable linear regression analysis and structural equation mode analysis were conducted to verify the association between different lipid-lowering strategies, Δhs-CRP (%) and ΔLDL-C (%). RESULTS: Totally, 3653 patients were enrolled with an average age of 63.81 years. Multivariable linear regression demonstrated that statin combined with ezetimibe therapy was significantly associated with decreased Δhs-CRP (%) (ß = -0.253, 95% CI: [-0.501 to -0.005], p = 0.045). The increased ΔLDL-C (%) was an independent predictor of elevated levels of Δhs-CRP (%) (ß = 0.487, 95% CI: [0.15-0.824], p = 0.005). Furthermore, structural equation model analysis proved that statin combined with ezetimibe therapy (ß = -0.300, p < 0.001) and intensive statin therapy (ß = -0.032, p = 0.043) had an indirect negative effect on Δhs-CRP via ΔLDL-C. CONCLUSIONS: Compared with routine statin use, statin combined with ezetimibe therapy and intensive statin therapy could further reduce hs-CRP levels.


Assuntos
Biomarcadores , Proteína C-Reativa , Doença da Artéria Coronariana , Ezetimiba , Inibidores de Hidroximetilglutaril-CoA Redutases , Intervenção Coronária Percutânea , Humanos , Masculino , Estudos Retrospectivos , Feminino , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/tratamento farmacológico , Pessoa de Meia-Idade , Biomarcadores/sangue , Resultado do Tratamento , Intervenção Coronária Percutânea/métodos , Ezetimiba/uso terapêutico , Quimioterapia Combinada , Idoso , Rosuvastatina Cálcica/uso terapêutico , Atorvastatina/uso terapêutico , LDL-Colesterol/sangue , Anticolesterolemiantes/uso terapêutico , Dislipidemias/sangue , Dislipidemias/tratamento farmacológico , Dislipidemias/diagnóstico
10.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38860832

RESUMO

Ferrite-loaded gyromagnetic nonlinear transmission line (GNLTL) provides a possible option to compress an input pulse to a narrower width for its remarkable sharpening effect. However, it is difficult to accurately predict the output of the GNLTL due to the complex interaction between the magnetic moment of ferrite and the bias magnetic field. In this paper, a finite element model of the GNLTL is established based on the Landau-Lifshitz-Gilbert equation to investigate the performance of the GNLTL. To validate this model, a prototype is used for experimental comparison. The result demonstrates good agreement between experiment and simulation. This paper further explores the influence of the bias magnetic field and the length of the GNLTL on the output pulse. Moreover, a method to sharpen the falling edge is proposed based on the reflection and superposition of the GNLTL output. Simulation and experimental results show its effectiveness and feasibility.

11.
Sci Adv ; 10(19): eadl3549, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38718121

RESUMO

Metabolic reprogramming is critical in the onset of pressure overload-induced cardiac remodeling. Our study reveals that proline dehydrogenase (PRODH), the key enzyme in proline metabolism, reprograms cardiomyocyte metabolism to protect against cardiac remodeling. We induced cardiac remodeling using transverse aortic constriction (TAC) in both cardiac-specific PRODH knockout and overexpression mice. Our results indicate that PRODH expression is suppressed after TAC. Cardiac-specific PRODH knockout mice exhibited worsened cardiac dysfunction, while mice with PRODH overexpression demonstrated a protective effect. In addition, we simulated cardiomyocyte hypertrophy in vitro using neonatal rat ventricular myocytes treated with phenylephrine. Through RNA sequencing, metabolomics, and metabolic flux analysis, we elucidated that PRODH overexpression in cardiomyocytes redirects proline catabolism to replenish tricarboxylic acid cycle intermediates, enhance energy production, and restore glutathione redox balance. Our findings suggest PRODH as a modulator of cardiac bioenergetics and redox homeostasis during cardiac remodeling induced by pressure overload. This highlights the potential of PRODH as a therapeutic target for cardiac remodeling.


Assuntos
Camundongos Knockout , Miócitos Cardíacos , Prolina , Remodelação Ventricular , Animais , Prolina/metabolismo , Miócitos Cardíacos/metabolismo , Camundongos , Ratos , Prolina Oxidase/metabolismo , Prolina Oxidase/genética , Metabolismo Energético , Miocárdio/metabolismo , Miocárdio/patologia , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Cardiomegalia/etiologia , Modelos Animais de Doenças , Oxirredução , Masculino , Reprogramação Metabólica
12.
J Craniofac Surg ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727237

RESUMO

OBJECTIVE: In a retrospective study of the effects of different treatment modalities of condylar fractures in childhood on mandibular symmetry and temporomandibular function, the cases selected for this article were adult patients who had sustained a condylar fracture in childhood. The aim was to investigate the effects of condylar fractures in children on the development and function of the mandible and their specific manifestations after the completion of mandibular development. METHODS: According to the different treatment modalities, the patients were divided into the conservative treatment group and the open surgical treatment group, and the effects of the 2 treatment modalities on the patients' condylar healing, the difference in growth ability, and the symmetry of the jaws were evaluated. The effects of different treatment modalities of children's condylar fracture on the growth, development, and function of the mandible were investigated using the Ai and Di, the grading of the imaging results, and the 3-dimensional CT fixation measurements from the aspects of both clinical examination and imaging examination. RESULTS: The 2 groups had condylar malalignment and condylar morphology abnormality, and there was one case of joint ankylosis in the surgical treatment group. There was a statistical difference in the evaluation of condylar reconstruction between the 2 groups, and the condylar reconstruction in the surgical treatment group was better than that in the conservative treatment, and there was a statistical difference between the condylar length, condylar width, condylar height, and depth of TMJ fossa between the healthy side and the affected side in the closed treatment group. There was a statistical difference in the height of the mandibular ascending branch between the healthy side and the affected side, and the unilateral condylar fracture was treated conservatively; the difference in the bony chin point deviation between the 2 groups was not statistically significant. CONCLUSION: In children, after conservative treatment of condylar fracture, the growth of condylar process is poor, and the condylar shape and position are not as good as surgical repositioning, but through the proliferation of temporomandibular joint fossa, it can make up for the insufficient height of condylar process, which has no effect on the symmetry of the mandible, and the surgical treatment can achieve good anatomical repositioning, which has a greater effect on the symmetry of the mandible than the conservative treatment.

13.
Front Med (Lausanne) ; 11: 1354037, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38765250

RESUMO

Background: Frailty is a complex geriatric syndrome that seriously affects the quality of life of older adults. Previous observational studies have reported a strong relationship of frailty with the gut microbiota; however, further studies are warranted to establish a causal link. Accordingly, we aimed to conduct a bidirectional Mendelian randomization study to assess the causal relationship between frailty, as measured by the frailty index, and gut microbiota composition. Methods: Instrumental variables for the frailty index (N = 175, 226) and 211 gut bacteria (N = 18,340) were obtained through a genome-wide association study. A two-sample Mendelian randomization analysis was performed to assess the causal relationship of gut microbiota with frailty. Additionally, we performed inverse Mendelian randomization analyses to examine the direction of causality. Inverse variance weighting was used as the primary method in this study, which was supplemented by horizontal pleiotropy and sensitivity analyses to increase confidence in the results. Results: Bacteroidia (b = -0.041, SE = 0.017, p = 0.014) and Eubacterium ruminantium (b = -0.027, SE = 0.012, p = 0.028) were protective against frailty amelioration. Additionally, the following five bacteria types were associated with high frailty: Betaproteobacteria (b = 0.049, SE = 0.024, p = 0.042), Bifidobacterium (b = 0.042, SE = 0.016, p = 0.013), Clostridium innocuum (b = 0.023, SE = 0.011, p = 0.036), E. coprostanoligenes (b = 0.054, SE = 0.018, p = 0.003), and Allisonella (b = 0.032, SE = 0.013, p = 0.012). Contrastingly, frailty affected Butyrivibrio in the gut microbiota (b = 1.225, SE = 0.570, p = 0.031). The results remained stable within sensitivity and validation analyses. Conclusion: Our findings strengthen the evidence of a bidirectional causal link between the gut microbiota and frailty. It is important to elucidate this relationship to optimally enhance the care of older adults and improve their quality of life.

14.
Physiol Meas ; 45(5)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38772402

RESUMO

Objective. Electroencephalography (EEG) is an important kind of bioelectric signal for measuring physiological activities of the brain, and motor imagery (MI) EEG has significant clinical application prospects. Convolutional neural network has become a mainstream algorithm for MI EEG classification, however lack of subject-specific data considerably restricts its decoding accuracy and generalization performance. To address this challenge, a novel transfer learning (TL) framework using auxiliary dataset to improve the MI EEG classification performance of target subject is proposed in this paper.Approach. We developed a multi-source deep domain adaptation ensemble framework (MSDDAEF) for cross-dataset MI EEG decoding. The proposed MSDDAEF comprises three main components: model pre-training, deep domain adaptation, and multi-source ensemble. Moreover, for each component, different designs were examined to verify the robustness of MSDDAEF.Main results. Bidirectional validation experiments were performed on two large public MI EEG datasets (openBMI and GIST). The highest average classification accuracy of MSDDAEF reaches 74.28% when openBMI serves as target dataset and GIST serves as source dataset. While the highest average classification accuracy of MSDDAEF is 69.85% when GIST serves as target dataset and openBMI serves as source dataset. In addition, the classification performance of MSDDAEF surpasses several well-established studies and state-of-the-art algorithms.Significance. The results of this study show that cross-dataset TL is feasible for left/right-hand MI EEG decoding, and further indicate that MSDDAEF is a promising solution for addressing MI EEG cross-dataset variability.


Assuntos
Eletroencefalografia , Processamento de Sinais Assistido por Computador , Eletroencefalografia/métodos , Humanos , Imaginação/fisiologia , Aprendizado Profundo , Atividade Motora/fisiologia , Algoritmos , Encéfalo/fisiologia
15.
iScience ; 27(5): 109678, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38660411

RESUMO

The liver is the main organ associated with metabolism. In our previous studies, we identified that the metabolic enzymes malate dehydrogenase 1 (MDH1) and isocitrate dehydrogenase 1 (IDH1) were differentially expressed in ALF. The aim of this study was to explore the changes in the acetylation of MDH1 and IDH1 and the therapeutic effect of histone deacetylase (HDAC) inhibitor in acute liver failure (ALF). Decreased levels of many metabolites were observed in ALF patients. MDH1 and IDH1 were decreased in the livers of ALF patients. The HDAC inhibitor ACY1215 improved the expression of MDH1 and IDH1 after treatment with MDH1-siRNA and IDH1-siRNA. Transfection with mutant plasmids and adeno-associated viruses, identified MDH1 K118 acetylation and IDH1 K93 acetylation as two important sites that regulate metabolism in vitro and in vivo.

16.
Nat Commun ; 15(1): 2854, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565554

RESUMO

The formation of carbon-hydrogen (C-H) bonds via the reaction of small inorganic molecules is of great significance for understanding the fundamental transition from inorganic to organic matter, and thus the origin of life. Yet, the detailed mechanism of the C-H bond formation, particularly the time scale and molecular-level control of the dynamics, remain elusive. Here, we investigate the light-induced bimolecular reaction starting from a van der Waals molecular dimer composed of two small inorganic molecules, H2 and CO. Employing reaction microscopy driven by a tailored two-color light field, we identify the pathways leading to C-H photobonding thereby producing HCO+ ions, and achieve coherent control over the reaction dynamics. Using a femtosecond pump-probe scheme, we capture the ultrafast formation time, i.e., 198 ± 16 femtoseconds. The real-time visualization and coherent control of the dynamics contribute to a deeper understanding of the most fundamental bimolecular reactions responsible for C-H bond formation, thus contributing to elucidate the emergence of organic components in the universe.

17.
STAR Protoc ; 5(2): 102963, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38568819

RESUMO

Recently, there has been a growing interest in using sustainable energy to decrease lignin monomers to generate high-value-added products. Here, we present a protocol for electrocatalytic hydrogenation of 5-hydroxymethylfurfural. We describe steps for catalyst preparation, performing electrocatalytic experiments, high-performance liquid chromatography analysis, and in situ infrared reflection-absorption spectroscopy testing. The synthesized catalyst used in this reaction exhibits enhanced selectivity and Faradaic efficiency in NaClO4 solution. For complete details on the use and execution of this protocol, please refer to Zhang et al.1.


Assuntos
Furaldeído , Furaldeído/análogos & derivados , Furaldeído/química , Catálise , Hidrogenação , Cromatografia Líquida de Alta Pressão/métodos , Técnicas Eletroquímicas/métodos
18.
Talanta ; 274: 125968, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38581849

RESUMO

Panax notoginseng (P. notoginseng), a Chinese herb containing various saponins, benefits immune system in medicines development, which from Wenshan (authentic cultivation) is often counterfeited by others for large demand and limited supply. Here, we proposed a method for identifying P. notoginseng origin combining terahertz (THz) precision spectroscopy and neural network. Based on the comparative analysis of four qualitative identification methods, we chose high-performance liquid chromatography (HPLC) and THz spectroscopy to detect 252 samples from five origins. After classifications using Convolutional Neural Networks (CNNs) model, we found that the performance of THz spectra was superior to that of HPLC. The underlying mechanism is that there are clear nonlinear relations among the THz spectra and the origins due to the wide spectra and multi-parameter characteristics, which makes the accuracy of five-classification origin identification up to 97.62%. This study realizes the rapid, non-destructive and accurate identification of P. notoginseng origin, providing a practical reference for herbal medicine.


Assuntos
Redes Neurais de Computação , Panax notoginseng , Espectroscopia Terahertz , Panax notoginseng/química , Espectroscopia Terahertz/métodos , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Algoritmos
19.
Front Neurosci ; 18: 1355052, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38456145

RESUMO

Introduction: Patients suffering from limb movement disorders require more complete rehabilitation treatment, and there is a huge demand for rehabilitation exoskeleton robots. Flexible and reliable motion control of exoskeleton robots is very important for patient rehabilitation. Methods: This paper proposes a novel exoskeleton robotic system for lower limb rehabilitation. The designed lower limb rehabilitation exoskeleton robot mechanism is mainly composed of the hip joint mechanism, the knee joint mechanism and the ankle joint mechanism. The forces and motion of the exoskeleton robot were analyzed in detail to determine its design parameters. The robot control system was developed to implement closed-loop position control and trajectory planning control of each joint mechanism. Results: Multiple experiments and tests were carried out to verify robot's performance and practicality. In the robot angular response experiments, the joint mechanism could quickly adjust to different desired angles, including 15°, 30°, 45°, and 60°. In the trajectory tracking experiments, the exoskeleton robot could complete tracking movements of typical actions such as walking, standing up, sitting down, go upstairs and go downstairs, with a maximum tracking error of ±5°. Robotic wearing tests on normal people were performed to verify the assistive effects of the lower limb rehabilitation exoskeleton at different stages. Discussion: The experimental results indicated that the exoskeleton robot has excellent reliability and practicality. The application of this exoskeleton robotic system will help paralyzed patients perform some daily movements and sports.

20.
Small ; : e2310082, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470193

RESUMO

Electrochemical conversion of nitrate, a prevalent water pollutant, to ammonia (NH3 ) is a delocalized and green path for NH3 production. Despite the existence of different nitrate reduction pathways, selectively directing the reaction pathway on the road to NH3 is now hindered by the absence of efficient catalysts. Single-atom catalysts (SACs) are extensively investigated in a wide range of catalytic processes. However, their application in electrocatalytic nitrate reduction reaction (NO3 - RR) to NH3 is infrequent, mostly due to their pronounced inclination toward hydrogen evolution reaction (HER). Here, Ni single atoms on the electrochemically active carrier boron, nitrogen doped-graphene (BNG) matrix to modulate the atomic coordination structure through a boron-spanning strategy to enhance the performance of NO3 - RR is designed. Density functional theory (DFT) study proposes that BNG supports with ionic characteristics, offer a surplus electric field effect as compared to N-doped graphene, which can ease the nitrate adsorption. Consistent with the theoretical studies, the as-obtained NiSA@BNG shows higher catalytic activity with a maximal NH3 yield rate of 168 µg h-1  cm-2 along with Faradaic efficiency of 95% and promising electrochemical stability. This study reveals novel ways to rationally fabricate SACs' atomic coordination structure with tunable electronic properties to enhance electrocatalytic performance.

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