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1.
Appl Opt ; 63(16): 4360-4365, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856614

RESUMO

The observation area of a point target, which is usually inaccessible, is a necessary condition when utilizing the conventional single-band infrared radiometric thermometry method, as the image gray level inevitably undergoes dispersion. Otherwise, significant errors will be generated, seriously affecting the applicability of infrared radiometric thermometry for distant point targets in the external field. To address the above issue, the infrared radiometric thermometry method for point targets has been researched. A point target radiometric thermometry method based on dual-band infrared imaging is proposed, which can effectively measure radiance and temperature when the area of the point target is unknown. The experimental results show that, compared with conventional single-band algorithms, the proposed dual-band point target thermometry algorithm has a maximum error of 11.18°C under the condition of unknown area, which can meet the needs of infrared radiometric thermometry of point targets at long distances in the external field.

2.
Nano Lett ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864413

RESUMO

Perovskite monocrystalline films are regarded as desirable candidates for the integration of high-performance optoelectronics due to their unique photophysical properties. However, the heterogeneous integration of a perovskite monocrystalline film with other semiconductors is fundamentally limited by the lattice mismatch, which hinders direct epitaxy. Herein, the van der Waals (vdW) integration strategy for 3D perovskites is developed, where perovskite monocrystalline films are epitaxially grown on the mother substrate, followed by its peeling off and transferring to arbitrary semiconductors, forming monocrystalline heterojunctions. The as-achieved CsPbBr3-Nb-doped SrTiO3 (Nb:STO) vdW p-n heterojunction exhibited comparable performance to their directly epitaxial counterpart, demonstrating the feasibility of vdW integration for 3D perovskites. Furthermore, the vdW integration could be extended to silicon substrates, rendering the CsPbBr3-n-Si and CsPbCl3-p-Si p-n heterojunction with apparent rectification behaviors and photoresponse. The vdW integration significantly enriches the selections of semiconductors hybridizing with perovskites and provides opportunities for monocrystalline perovskite optoelectronics with complex configurations and multiple functionalities.

3.
Front Immunol ; 15: 1310376, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720887

RESUMO

Introduction: Hypopharyngeal squamous cell carcinoma (HSCC) is one of the malignant tumors with the worst prognosis in head and neck cancers. The transformation from normal tissue through low-grade and high-grade intraepithelial neoplasia to cancerous tissue in HSCC is typically viewed as a progressive pathological sequence typical of tumorigenesis. Nonetheless, the alterations in diverse cell clusters within the tissue microenvironment (TME) throughout tumorigenesis and their impact on the development of HSCC are yet to be fully understood. Methods: We employed single-cell RNA sequencing and TCR/BCR sequencing to sequence 60,854 cells from nine tissue samples representing different stages during the progression of HSCC. This allowed us to construct dynamic transcriptomic maps of cells in diverse TME across various disease stages, and experimentally validated the key molecules within it. Results: We delineated the heterogeneity among tumor cells, immune cells (including T cells, B cells, and myeloid cells), and stromal cells (such as fibroblasts and endothelial cells) during the tumorigenesis of HSCC. We uncovered the alterations in function and state of distinct cell clusters at different stages of tumor development and identified specific clusters closely associated with the tumorigenesis of HSCC. Consequently, we discovered molecules like MAGEA3 and MMP3, pivotal for the diagnosis and treatment of HSCC. Discussion: Our research sheds light on the dynamic alterations within the TME during the tumorigenesis of HSCC, which will help to understand its mechanism of canceration, identify early diagnostic markers, and discover new therapeutic targets.


Assuntos
Carcinogênese , Neoplasias Hipofaríngeas , Análise de Célula Única , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Masculino , Biomarcadores Tumorais/genética , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hipofaríngeas/genética , Neoplasias Hipofaríngeas/patologia , Neoplasias Hipofaríngeas/imunologia , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/metabolismo , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Análise de Sequência de RNA , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Transcriptoma , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética
4.
J Virol ; 98(6): e0057624, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38767375

RESUMO

Kaposi sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus-8, is the causal agent of Kaposi sarcoma, a cancer that appears as tumors on the skin or mucosal surfaces, as well as primary effusion lymphoma and KSHV-associated multicentric Castleman disease, which are B-cell lymphoproliferative disorders. Effective prophylactic and therapeutic strategies against KSHV infection and its associated diseases are needed. To develop these strategies, it is crucial to identify and target viral glycoproteins involved in KSHV infection of host cells. Multiple KSHV glycoproteins expressed on the viral envelope are thought to play a pivotal role in viral infection, but the infection mechanisms involving these glycoproteins remain largely unknown. We investigated the role of two KSHV envelope glycoproteins, KSHV complement control protein (KCP) and K8.1, in viral infection in various cell types in vitro and in vivo. Using our newly generated anti-KCP antibodies, previously characterized anti-K8.1 antibodies, and recombinant mutant KSHV viruses lacking KCP, K8.1, or both, we demonstrated the presence of KCP and K8.1 on the surface of both virions and KSHV-infected cells. We showed that KSHV lacking KCP and/or K8.1 remained infectious in KSHV-susceptible cell lines, including epithelial, endothelial, and fibroblast, when compared to wild-type recombinant KSHV. We also provide the first evidence that KSHV lacking K8.1 or both KCP and K8.1 can infect human B cells in vivo in a humanized mouse model. Thus, these results suggest that neither KCP nor K8.1 is required for KSHV infection of various host cell types and that these glycoproteins do not determine KSHV cell tropism. IMPORTANCE: Kaposi sarcoma-associated herpesvirus (KSHV) is an oncogenic human gamma-herpesvirus associated with the endothelial malignancy Kaposi sarcoma and the lymphoproliferative disorders primary effusion lymphoma and multicentric Castleman disease. Determining how KSHV glycoproteins such as complement control protein (KCP) and K8.1 contribute to the establishment, persistence, and transmission of viral infection will be key for developing effective anti-viral vaccines and therapies to prevent and treat KSHV infection and KSHV-associated diseases. Using newly generated anti-KCP antibodies, previously characterized anti-K8.1 antibodies, and recombinant mutant KSHV viruses lacking KCP and/or K8.1, we show that KCP and K8.1 can be found on the surface of both virions and KSHV-infected cells. Furthermore, we show that KSHV lacking KCP and/or K8.1 remains infectious to diverse cell types susceptible to KSHV in vitro and to human B cells in vivo in a humanized mouse model, thus providing evidence that these viral glycoproteins are not required for KSHV infection.


Assuntos
Herpesvirus Humano 8 , Sarcoma de Kaposi , Proteínas do Envelope Viral , Proteínas Virais , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/fisiologia , Humanos , Animais , Camundongos , Proteínas Virais/metabolismo , Proteínas Virais/genética , Sarcoma de Kaposi/virologia , Proteínas do Envelope Viral/metabolismo , Proteínas do Envelope Viral/genética , Linhagem Celular , Hiperplasia do Linfonodo Gigante/virologia , Hiperplasia do Linfonodo Gigante/metabolismo , Infecções por Herpesviridae/virologia , Infecções por Herpesviridae/metabolismo , Células HEK293 , Células Endoteliais/virologia
5.
Sci Rep ; 14(1): 10909, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740903

RESUMO

To improve the recognition effect of the folk dance image recognition model and put forward new suggestions for teachers' teaching strategies, this study introduces a Deep Neural Network (DNN) to optimize the folk dance training image recognition model. Moreover, a corresponding teaching strategy optimization scheme is proposed according to the experimental results. Firstly, the image preprocessing and feature extraction of DNN are optimized. Secondly, classification and target detection models are established to analyze the folk dance training images, and the C-dance dataset is used for experiments. Finally, the results are compared with those of the Naive Bayes classifier, K-nearest neighbor, decision tree classifier, support vector machine, and logistic regression models. The results of this study provide new suggestions for teaching strategies. The research results indicate that the optimized classification model shows a significant improvement in classification accuracy across various aspects such as action complexity, dance types, movement speed, dance styles, body dynamics, and rhythm. The accuracy, precision, recall, and F1 scores have increased by approximately 14.7, 11.8, 13.2, and 17.4%, respectively. In the study of factors such as different training images, changes in perspective, lighting conditions, and noise interference, the optimized model demonstrates a substantial enhancement in recognition accuracy and robustness. These findings suggest that, compared to traditional models, the optimized model performs better in identifying various dances and movements, enhancing the accuracy and stability of classification. Based on the experimental results, strategies for optimizing the real-time feedback and assessment mechanism in folk dance teaching, as well as the design of personalized learning paths, are proposed. Therefore, this study holds the potential to be applied in the field of folk dance, promoting the development and innovation of folk dance education.


Assuntos
Dança , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Humanos , Processamento de Imagem Assistida por Computador/métodos , Aprendizado Profundo , Ensino
7.
Phytochemistry ; 223: 114120, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38705265

RESUMO

Eleven previously undescribed sesquiterpenoids (8-18), one undescribed jasmonic acid derivative (35) and 28 known compounds were isolated from the leaves of Artemisia stolonifera. Undescribed compounds with their absolute configurations were determined by extensive spectroscopic analysis, single-crystal X-ray diffraction and ECD calculation. Compound 8 was identified as a rare sesquiterpenoid featuring a rearranged 5/8 bicyclic ring system, whereas compound 17 was found to be an unprecedented monocyclic sesquiterpenoid with methyl rearrangement. Evaluation of biological activity showed that compounds 1-5 and 7 displayed cytotoxicity against six tumor cells. In the meantime, compounds 11, 12, 18 and 35 exhibited inhibitory effects against LPS-stimulated NO production in RAW 264.7 macrophage cells and reduced the transcription of IL-6 and IL-1ß in a dose-dependent manner at 25, 50 and 100 µM. Moreover, the anti-inflammatory-based network pharmacology and molecular docking analyses revealed potential target proteins of 11, 12, 18 and 35.


Assuntos
Anti-Inflamatórios , Artemisia , Ciclopentanos , Óxido Nítrico , Oxilipinas , Sesquiterpenos , Artemisia/química , Camundongos , Oxilipinas/farmacologia , Oxilipinas/química , Oxilipinas/isolamento & purificação , Animais , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Ciclopentanos/química , Ciclopentanos/farmacologia , Ciclopentanos/isolamento & purificação , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Estrutura Molecular , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Humanos , Relação Dose-Resposta a Droga , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Folhas de Planta/química , Ensaios de Seleção de Medicamentos Antitumorais
8.
Int J Biol Macromol ; 269(Pt 1): 131994, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38697431

RESUMO

Nowadays, dye water pollution is becoming increasingly severe. Composite of MXene, ZnS, and chitosan-cellulose material (MX/ZnS/CC) was developed to remove anionic dyes through the synergistic effect of adsorption and photocatalytic degradation. MXene was introduced as the cocatalyst to form Schottky heterostructure with ZnS for improving the separation efficiency of photocarriers and photocatalytic performance. Chitosan-cellulose material mainly served as the dye adsorbent, while also could improve material stability and assist in generation of free radicals for dye degradation. The physics and chemistry properties of MX/ZnS/CC composite were systematically inspected through various characterizations. MX/ZnS/CC composite exhibited good adsorption ability to anionic dyes with adsorption capacity up to 1.29 g/g, and excellent synergistic effects of adsorption and photodegradation with synergistic removal capacity up to 5.63 g/g. MX/ZnS/CC composite performed higher synergistic removal ability and better optical and electrical properties than pure MXene, ZnS, chitosan-cellulose material, and MXene/ZnS. After compounding, the synergistic removal percentage of dyes increased by a maximum of 309 %. MX/ZnS/CC composite mainly adsorbs anionic dyes through electrostatic interactions and catalyzes the generation of •O2-, h+, and •OH to degrade dyes, which has been successfully used to remove anionic dyes from environmental water, achieving a 100 % removal of 50 mg/L dye.


Assuntos
Celulose , Quitosana , Corantes , Poluentes Químicos da Água , Compostos de Zinco , Quitosana/química , Adsorção , Celulose/química , Compostos de Zinco/química , Corantes/química , Corantes/isolamento & purificação , Catálise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Sulfetos/química , Purificação da Água/métodos , Fotólise , Ânions/química
9.
J Phys Chem Lett ; 15(15): 4088-4095, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38587462

RESUMO

Although it is generally acknowledged that transition metals at high oxidation states represent superior oxygen evolution reaction (OER) activity, the preparation and stability of such a high-valence state are still a challenge, which requires relatively harsh reaction conditions and is unstable under ambient conditions. Herein, we report the formation of trivalent nickel (Ni3+) in laser-fabricated nickel oxides induced by polyaniline (PANI) under electrochemical activation via a significant charge transfer between Ni and N, as confirmed by X-ray photoelectron spectroscopy and density functional theory calculations. Thereafter, the presence of Ni3+ and the improved conductivity by PANI effectively increase the electrochemical OER activity of the samples together with excellent long-term stability. This work provides new insights for the rational manufacture of high-valence metal for electrochemical reactions.

10.
Sci Bull (Beijing) ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38637224

RESUMO

Orderly hierarchical structure with balanced mechanical, chemical, and electrical properties is the basis of the natural bone microenvironment. Inspired by nature, we developed a piezocatalytically-induced controlled mineralization strategy using piezoelectric polymer poly-L-lactic acid (PLLA) fibers with ordered micro-nano structures to prepare biomimetic tissue engineering scaffolds with a bone-like microenvironment (pcm-PLLA), in which PLLA-mediated piezoelectric catalysis promoted the in-situ polymerization of dopamine and subsequently regulated the controllable growth of hydroxyapatite crystals on the fiber surface. PLLA fibers, as analogs of mineralized collagen fibers, were arranged in an oriented manner, and ultimately formed a bone-like interconnected pore structure; in addition, they also provided bone-like piezoelectric properties. The uniformly sized HA nanocrystals formed by controlled mineralization provided a bone-like mechanical strength and chemical environment. The pcm-PLLA scaffold could rapidly recruit endogenous stem cells, and promote their osteogenic differentiation by activating cell membrane calcium channels and PI3K signaling pathways through ultrasound-responsive piezoelectric signals. In addition, the scaffold also provided a suitable microenvironment to promote macrophage M2 polarization and angiogenesis, thereby enhancing bone regeneration in skull defects of rats. The proposed piezocatalytically-induced controllable mineralization strategy provides a new idea for the development of tissue engineering scaffolds that can be implemented for multimodal physical stimulation therapy.

11.
Front Microbiol ; 15: 1339621, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650882

RESUMO

Background: Cutaneous melanoma (CM) of the skin stands as the leading cause of mortality among skin cancer-related deaths. Despite the successes achieved with novel therapies such as immunotherapy and targeted therapy, their efficacy remains limited, necessitating further exploration of new treatment modalities. The gut microbiota and CM may be linked, as indicated by a growing body of preclinical and observational research. Nevertheless, the exact correlation between the intestinal microbiota and CM remains to be determined. Therefore, this study aims to assess the potential causal relationship between the gut microbiota and CM. Methods: The study utilized exposure data obtained from the MiBioGen consortium's microbiome GWAS, which included a total of 18,340 samples gathered from 24 population-based cohorts. Data at the summary level for CM were acquired from the UK Biobank investigation. The main analytical strategy utilized in this research was the inverse variance weighted (IVW) technique, supported by quality assurance measures like the weighted median model, MR-Egger, simple model, and weighted model approaches. The Cochran's Q test was used to evaluate heterogeneity. To ascertain potential pleiotropy, we employed both the MR-Egger regression and the MR-PRESSO test. Sensitivity analysis was conducted using the leave-one-out method. Results: The study found that the class Bacteroidia (OR = 0.997, 95% CI: 0.995-0.999, p = 0.027), genus Parabacteroides (OR = 0.997, 95% CI: 0.994-0.999, p = 0.037), order Bacteroidales (OR = 0.997, 95% CI: 0.995-0.999, p = 0.027), and genus Veillonella (OR = 0.998, 95% CI: 0.996-0.999, p = 0.046) have protective effects on CM. On the order hand, the genus Blautia (OR = 1.003, 95% CI: 1-1.006, p = 0.001) and phylum Cyanobacteria (OR = 1.002, 95% CI: 1-1.004, p = 0.04) are identified as risk factors for CM. Conclusion: We comprehensively assessed the potential causal relationship between the gut microbiota and CM and identified associations between six gut microbiota and CM. Among these, four gut microbiota were identified as protective factors for CM, while two gut microbiota were identified as risk factors for CM. This study effectively established a causal relationship between the gut microbiota and CM, thereby providing valuable insights into the mechanistic pathways through which the microbiota impacts the progression of CM.

12.
Biomater Res ; 28: 0013, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617751

RESUMO

Background: Fibrosis and inflammation due to ureteropelvic junction obstruction substantially contributes to poor renal function. Urine-derived stem-cell-derived exosomes (USC-Exos) have therapeutic effects through paracrine. Methods: In vitro, the effects of USC-Exos on the biological functions of HK-2 and human umbilical vein endothelial cells were tested. Cell inflammation and fibrosis were induced by transforming growth factor-ß1 and interleukin-1ß, and their anti-inflammatory and antifibrotic effects were observed after exogenous addition of USC-Exos. Through high-throughput sequencing of microRNA in USC-Exos, the pathways and key microRNAs were selected. Then, the antifibrotic and anti-inflammatory effects of exosomal miR-122-5p and target genes were verified. The role of the miR-122-5p/SOX2 axis in anti-inflammatory and antifibrotic effects was verified. In vivo, a rabbit model of partial unilateral ureteral obstruction (PUUO) was established. Magnetic resonance imaging recorded the volume of the renal pelvis after modeling, and renal tissue was pathologically analyzed. Results: We examined the role of USC-Exos and their miR-122-5p content in obstructive kidney injury. These Exos exhibit antifibrotic and anti-inflammatory activities. SOX2 is the hub gene in PUUO and negatively related to renal function. We confirmed the binding relationship between miR-122-5p and SOX2. The anti-inflammatory and antifibrotic effects of miR-122-5p were inhibited, indicating that miR-122-5p has anti-inflammatory and antifibrotic effects by inhibiting SOX2 expression. In vivo, the PUUO group showed typical obstructive kidney injury after modeling. After USC-Exo treatment, the shape of the renal pelvis shown a remarkable improvement, and inflammation and fibrosis decreased. Conclusions: We confirmed that miR-122-5p from USC-Exos targeting SOX2 is a new molecular target for postoperative recovery treatment of obstructive kidney injury.

13.
Eur Respir Rev ; 33(171)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38537947

RESUMO

COPD poses a significant global public health challenge, primarily characterised by irreversible airflow restriction and persistent respiratory symptoms. The hallmark pathology of COPD includes sustained airway inflammation and the eventual destruction of lung tissue structure. While multiple risk factors are implicated in the disease's progression, the underlying mechanisms remain largely elusive. The perpetuation of inflammation is pivotal to the advancement of COPD, emphasising the importance of investigating these self-sustaining mechanisms for a deeper understanding of the pathogenesis. Autoimmune responses constitute a critical mechanism in maintaining inflammation, with burgeoning evidence pointing to their central role in COPD progression; yet, the intricacies of these mechanisms remain inadequately defined. This review elaborates on the evidence supporting the presence of autoimmune processes in COPD and examines the potential mechanisms through which autoimmune responses may drive the chronic inflammation characteristic of the disease. Moreover, we attempt to interpret the clinical manifestations of COPD through autoimmunity.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Humanos , Autoimunidade , Pulmão/patologia , Fatores de Risco , Inflamação
14.
Front Microbiol ; 15: 1357579, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529180

RESUMO

Potato early blight (PEB), a foliar disease of potato during the growing period, caused by Alternaria sp., is common in major potato-producing areas worldwide. Effective agents to control this disease or completely resistant potato varieties are absent. Large-scale use of fungicides is limited due to possibility of increase in pathogen resistance and the requirements of ecological agriculture. In this study, we focused on the composition and infection characteristics of early blight pathogens in Yunnan Province and screened candidate pathogenesis-related pathways and genes. We isolated 85 strains of Alternaria sp. fungi from typical early blight spots in three potato-growing regions in Yunnan Province from 2018 to 2022, and identified 35 strains of Alternaria solani and 50 strains of Alternaria alternata by morphological characterization and ITS sequence comparison, which were identified as the main and conditional pathogens causing early blight in potato, respectively. Scanning electron microscope analysis confirmed only A. solani producing appressorium at 4 h after inoculation successfully infected the leaf cells. Via genome assembly and annotation, combine transcriptome and proteomic analysis, the following pathogenicity-related unit, transcription factors and metabolic pathway were identified: (1) cell wall-degrading enzymes, such as pectinase, keratinase, and cellulase; (2) genes and pathways related to conidia germination and pathogenicity, such as ubiquitination and peroxisomes; and (3) transcription factors, such as Zn-clus, C2H2, bZIP, and bHLH. These elements were responsible for PEB epidemic in Yunnan.

15.
J Biomech ; 166: 112047, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38484653

RESUMO

To maintain the physiological dynamics of the mitral annulus, mitral annuloplasty rings (MAR) must be flexible. Enhanced flexibility implies decreased resistance to fatigue and potential for fatigue fracture. This study established new methods to test the flexible fatigue life of MAR in-vitro using numerical analysis; the purpose is that the fatigue test could reflect the real stress distribution in-vivo. Based on the conventional test methods (C1, D1), this paper presents a novel test method (C2, D2). Four testing methods for open-end annuloplasty rings (C1, C2) and closed-end annuloplasty rings (D1, D2) were modelled and their stress distribution calculated by finite element analysis. The mean absolute error (Χ) and the Pearson correlation coefficient (Φ) were used to quantify the difference in stress distribution between the loading modes in-vivo and in-vitro. For closed-end annuloplasty rings, the novel test method (D2) is not obvious better than conventional test methods(D1) in duplicating the stress distribution (ΦD1 = 0.88 vs ΦD2 = 0.92). However, the maximum values of stress in the novel test method are closer to the maximum value of stress under in-vivo loading (ΧD1 = 5.2Mpa vs ΧD2 = 4.4Mpa). For open-end annuloplasty rings, the novel test method(C2) is obviously superior to the conventional test method(C1) in duplicating both the stress distribution and the stress peak values of the in-vivo loading (ΦC1 = 0.22 vs ΦC2 = 0.98; ΧC1 = 59.1Mpa vs ΧC2 = 11.0Mpa). The in-vitro loading methods described in this article more closely approximated in-vivo conditions compared to traditional methods. They are simpler to operate, more efficient and can help manufacturers expedite new product development, assist regulatory agencies with product quality oversight.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Anuloplastia da Valva Mitral , Insuficiência da Valva Mitral , Humanos , Desenho de Prótese , Anuloplastia da Valva Mitral/métodos , Valva Mitral/cirurgia , Valva Mitral/fisiologia , Teste de Materiais , Insuficiência da Valva Mitral/cirurgia
16.
Protoplasma ; 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38492055

RESUMO

Dichondra (Dichondra repens) is an important ground cover plant for landscaping and establishment of green space, but adaptive mechanism of drought tolerance is not well understood in this species. This study was conducted to compare differential response to drought stress among three genotypes (Dr5, Duliujiang, and Dr29) based on integrated physiological, ultrastructural, and metabolic assays. Results showed that drought significantly inhibited photosynthesis, accelerated lipids peroxidation, and also disrupted water balance and cellular metabolism in dichondra plants. Dr5 showed better photochemical efficiency of photosystem II and water homeostasis, less oxidative damage, and more stable chlorophyll metabolism than Duliujinag or Dr29 in response to drought stress. In addition, Dr5 accumulated more amino acids, organic acids, and other metabolites, which was good for maintaining better antioxidant capacity, osmotic homeostasis, and energy metabolism under drought stress. Drought tolerance of Duliujiang was lower than Dr5, but better than Dr29, which could be positively correlated with accumulations of sucrose, maltitol, aconitic acid, isocitric acid, and shikimic acid due to critical roles of these metabolites in osmotic adjustment and metabolic homeostasis. Current findings provide insights into understanding of underlying mechanism of metabolic regulation in dichondra species. Dr5 could be used as an important drought-tolerant resource for cultivation and water-saving breeding.

17.
Sci Bull (Beijing) ; 69(9): 1342-1352, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490891

RESUMO

The Schottky contact which is a crucial interface between semiconductors and metals is becoming increasingly significant in nano-semiconductor devices. A Schottky barrier, also known as the energy barrier, controls the depletion width and carrier transport across the metal-semiconductor interface. Controlling or adjusting Schottky barrier height (SBH) has always been a vital issue in the successful operation of any semiconductor device. This review provides a comprehensive overview of the static and dynamic adjustment methods of SBH, with a particular focus on the recent advancements in nano-semiconductor devices. These methods encompass the work function of the metals, interface gap states, surface modification, image-lowering effect, external electric field, light illumination, and piezotronic effect. We also discuss strategies to overcome the Fermi-level pinning effect caused by interface gap states, including van der Waals contact and 1D edge metal contact. Finally, this review concludes with future perspectives in this field.

18.
ACS Sens ; 9(3): 1301-1309, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38373043

RESUMO

Continuous pulse wave detection can be used for monitoring and diagnosing cardiovascular diseases, and research on pulse sensing based on piezoelectric thin films is one of the hot spots. Usually, piezoelectric thin films do not come into direct contact with the skin and need to be connected through a layer of an elastic medium. Most views think that the main function of this layer of elastic medium is to increase the adhesion between the sensor component and the skin, but there is little discussion about the impact of the elastic medium on pulse vibration transmission. Here, we conducted a detailed study on the effects of Young's modulus and the thickness of elastic media on pulse sensing signals. The results show that the waveform amplitude of the piezoelectric sensing signal decreases with the increase of Young's modulus and thickness of the elastic medium. Then, we constructed a theoretical model of the influence of elastic media on pulse wave propagation. The amplitude of the pulse wave signal detected by the optimized sensor was increased to 480%. Our research shows that by regulating Young's modulus and thickness of elastic media, pulse wave signals can undergo a similar amplification effect, which has an important theoretical reference value for achieving ambulatory blood pressure monitoring based on high-quality pulse waves.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Elastômeros , Razão Sinal-Ruído , Módulo de Elasticidade , Modelos Teóricos
19.
Small Methods ; : e2301682, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332438

RESUMO

Triboelectric nanogenerators (TENGs) can collect and convert random mechanical energy into electric energy, with remarkable advantages including broadly available materials, straightforward preparation, and multiple applications. Over the years, researchers have made substantial advancements in the theoretical and practical aspects of TENG. Nevertheless, the pivotal challenge in realizing full applications of TENG lies in ensuring that the generated output meets the specific application requirements. Consequently, substantial research is dedicated to exploring methods and mechanisms for enhancing the output performance of TENG devices. This review aims to comprehensively examine the influencing factors and corresponding improvement strategies of the output performance based on the contact electrification mechanism and operational principles that underlie TENG technology. This review primarily delves into five key areas of improvement: materials selection, surface modification, component adjustments, structural optimization, and electrode enhancements. These aspects are crucial in tailoring TENG devices to meet the desired performance metrics for various applications.

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