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1.
Front Plant Sci ; 14: 1257212, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900761

RESUMO

Accurate detection of tea diseases is essential for optimizing tea yield and quality, improving production, and minimizing economic losses. In this paper, we introduce TeaDiseaseNet, a novel disease detection method designed to address the challenges in tea disease detection, such as variability in disease scales and dense, obscuring disease patterns. TeaDiseaseNet utilizes a multi-scale self-attention mechanism to enhance disease detection performance. Specifically, it incorporates a CNN-based module for extracting features at multiple scales, effectively capturing localized information such as texture and edges. This approach enables a comprehensive representation of tea images. Additionally, a self-attention module captures global dependencies among pixels, facilitating effective interaction between global information and local features. Furthermore, we integrate a channel attention mechanism, which selectively weighs and combines the multi-scale features, eliminating redundant information and enabling precise localization and recognition of tea disease information across diverse scales and complex backgrounds. Extensive comparative experiments and ablation studies validate the effectiveness of the proposed method, demonstrating superior detection results in scenarios characterized by complex backgrounds and varying disease scales. The presented method provides valuable insights for intelligent tea disease diagnosis, with significant potential for improving tea disease management and production.

2.
Microb Cell Fact ; 22(1): 95, 2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37149632

RESUMO

BACKGROUND: Engineered strains of Escherichia coli have been used to produce bioconjugate vaccines using Protein Glycan Coupling Technology (PGCT). Nanovaccines have also entered the vaccine development arena with advances in nanotechnology and have been significantly developed, but chassis cells for conjugate nanovaccines have not been reported. RESULTS: To facilitate nanovaccine preparation, a generic recombinant protein (SpyCather4573) was used as the acceptor protein for O-linked glycosyltransferase PglL, and a glycol-engineered Escherichia coli strain with these two key components (SC4573 and PglL) integrated in its genome was developed in this study. The targeted glycoproteins with antigenic polysaccharides produced by our bacterial chassis can be spontaneously bound to proteinous nanocarriers with surface exposed SpyTag in vitro to form conjugate nanovaccines. To improve the yields of the targeted glycoprotein, a series of gene cluster deletion experiments was carried out, and the results showed that the deletion of the yfdGHI gene cluster increased the expression of glycoproteins. Using the updated system, to the best of our knowledge, we report for the first time the successful preparation of an effective Klebsiella pneumoniae O1 conjugate nanovaccine (KPO1-VLP), with antibody titers between 4 and 5 (Log10) after triple immunization and up to 100% protection against virulent strain challenge. CONCLUSIONS: Our results define a convenient and reliable framework for bacterial glycoprotein vaccine preparation that is flexible and versatile, and the genomic stability of the engineered chassis cells promises a wide range of applications for biosynthetic glycobiology research.


Assuntos
Escherichia coli , Klebsiella pneumoniae , Escherichia coli/metabolismo , Klebsiella pneumoniae/genética , Vacinas Conjugadas , Vacinas Bacterianas , Polissacarídeos/metabolismo , Glicóis/metabolismo
3.
Comput Math Methods Med ; 2022: 4435722, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277007

RESUMO

Objective: To evaluate the effect of hemp cotton sanitary pads on the vaginal microecology. Methods: A randomized controlled field trial was used to recruit 1002 community-based women of childbearing age. The women were randomly divided into experimental and control groups. The experimental group used hemp cotton sanitary pads, while the control group used two types of cotton sanitary randomly chosen from the top five sanitary pads in terms of market share in China. The vaginal microecology was compared between the two groups after three months. Results: According to the vaginal microecologic examination results at baseline, 1002 women were included in 3 groups: normal vaginal microecologic, vaginal microecological disorders, and suspected vaginal infections. The number of patients in three groups were 39 (3.9%), 652 (65.1%), and 311 (31%), respectively. Three months later, the vaginal microecologic status and vaginal pH value of the suspected vaginal infection group were not significantly different between the experimental group and control group. The experimental group outperformed the control group with respect to vaginal cleanliness and vaginal microecology status in the women without a vaginal infection (normal vaginal microecology or microecological disorders group). The rate of abnormal cleanliness in the experimental group was lower than the control group (31.95% [108/338] vs. 43.62% [154/353]). The incidence of suspected vaginitis in the experimental group was lower than the control group (15.29% [51/338] vs. 23.51% [83/353]). Conclusion: For women without vaginal inflammation, the use of hemp cotton sanitary pads during menstruation can help maintain the balance of the vaginal microecology to prevent reproductive tract infections.


Assuntos
Cannabis , Humanos , Feminino , Produtos de Higiene Menstrual , Vagina , Menstruação , China
4.
Nanomaterials (Basel) ; 12(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35269221

RESUMO

Proteinaceous nanovaccine delivery systems have significantly promoted the development of various high-efficiency vaccines. However, the widely used method of coupling the expression of scaffolds and antigens may result in their structural interference with each other. Monovalent streptavidin (mSA) is a short monomer sequence, which has a strong affinity for biotin. Here, we discuss an orthogonal, modular, and highly versatile self-assembled proteinaceous nanoparticle chassis that facilitates combinations with various antigen cargos by using mSA and biotin to produce nanovaccines. We first improved the yield of these nanoparticles by appending a short sugar chain on their surfaces in a constructed host strain. After confirming the strong ability to induce both Th1- and Th2-mediated immune responses based on the plasma cytokine spectrum from immunized mice, we further verified the binding ability of biotinylated nanoparticles to mSA-antigens. These results demonstrate that our biotinylated nanoparticle chassis could load both protein and polysaccharide antigens containing mSA at a high affinity. Our approach thus offers an attractive technology for combining nanoparticles and antigen cargos to generate various high-performance nanovaccines. In particular, the designed mSA connector (mSA containing glycosylation modification sequences) could couple with polysaccharide antigens, providing a new attractive strategy to prepare nanoscale conjugate vaccines.

5.
Comput Intell Neurosci ; 2021: 8813806, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381499

RESUMO

Class imbalance and concept drift are two primary principles that exist concurrently in data stream classification. Although the two issues have drawn enough attention separately, the joint treatment largely remains unexplored. Moreover, the class imbalance issue is further complicated if data streams with concept drift. A novel Cost-Sensitive based Data Stream (CSDS) classification is introduced to overcome the two issues simultaneously. The CSDS considers cost information during the procedures of data preprocessing and classification. During the data preprocessing, a cost-sensitive learning strategy is introduced into the ReliefF algorithm for alleviating the class imbalance at the data level. In the classification process, a cost-sensitive weighting schema is devised to enhance the overall performance of the ensemble. Besides, a change detection mechanism is embedded in our algorithm, which guarantees that an ensemble can capture and react to drift promptly. Experimental results validate that our method can obtain better classification results under different imbalanced concept drifting data stream scenarios.


Assuntos
Algoritmos , Aprendizagem , Humanos
6.
Artigo em Inglês | MEDLINE | ID: mdl-34122604

RESUMO

OBJECTIVE: This survey was designed and conducted with an aim to present data on sexual desire and activity in Chinese women. METHODS: Between October 2013 and December 2013, we surveyed 3000 women (aged 40-65 years) at Beijing No. 2 Hospital and the Yuetan Community Health Service Center using a questionnaire. The primary outcomes included determination of sexual desire in the past 4 weeks, reasons for stopping sexual activity, and postmenopausal syndrome. The secondary outcome was determination of factors for low sexual desire. RESULTS: A total of 2400 women (mean age 54.33 ± 6.25 years; mean menopausal age 50.11 ± 3.31 years) returned the questionnaire, with 58% of women reporting lowered sexual desire and 39.3% reporting stoppage of sexual activity. Compared with the postmenopausal group, the incidence of anxiety, depressive, somatic, and vasomotor symptoms was higher in the perimenopausal group. Muscle and joint pain (45.8%) and vaginal pruritus (21.5%) were the most commonly reported menopausal and vulvovaginal symptoms, respectively. The odds of decrease in sexual desire were significantly higher with older age, menopause, presence of gynecological disease, menopausal depression symptoms, menopausal vasomotor symptoms, and vulvovaginal atrophy; only cesarean delivery (odds ratio = 0.887, P=0.018) was associated with lesser reduction in sexual desire compared with the aforementioned factors. CONCLUSION: This survey showed that a high proportion of Chinese middle-aged and old women have lowered sexual desire and activity. Lack of sexual desire is associated with multiple factors and affects the quality of life of women.

7.
Comput Intell Neurosci ; 2018: 4276291, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977276

RESUMO

It is common in real-world data streams that previously seen concepts will reappear, which suggests a unique kind of concept drift, known as recurring concepts. Unfortunately, most of existing algorithms do not take full account of this case. Motivated by this challenge, a novel paradigm was proposed for capturing and exploiting recurring concepts in data streams. It not only incorporates a distribution-based change detector for handling concept drift but also captures recurring concept by storing recurring concepts in a classifier graph. The possibility of detecting recurring drifts allows reusing previously learnt models and enhancing the overall learning performance. Extensive experiments on both synthetic and real-world data streams reveal that the approach performs significantly better than the state-of-the-art algorithms, especially when concepts reappear.


Assuntos
Algoritmos , Processamento Eletrônico de Dados/métodos , Fatores de Tempo
8.
Langmuir ; 32(30): 7503-11, 2016 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-27434752

RESUMO

In this paper, the detailed behaviors of all the molecules, especially the interfacial array behaviors of surfactants and diffusion behaviors of gas molecules, in foam systems with different gases (N2, O2, and CO2) being used as foaming agents were investigated by combining molecular dynamics simulation and experimental approaches for the purpose of interpreting how the molecular behaviors effect the properties of the foam and find out the key factors which fundamentally determine the foam stability. Sodium dodecyl sulfate SDS was used as the foam stabilizer. The foam decay and the drainage process were determined by Foamscan. A texture analyzer (TA) was utilized to measure the stiffness and viscoelasticity of the foam films. The experimental results agreed very well with the simulation results by which how the different gas components affect the interfacial behaviors of surfactant molecules and thereby bring influence on foam properties was described.

9.
Colloids Surf B Biointerfaces ; 141: 206-212, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26852104

RESUMO

The foam properties, such as the foamability, foam stability, drainage, coalescence and bulk rheology, of aqueous solutions containing an eco-friendly exopolysaccharide (EPS) secreted by a deep-sea mesophilic bacterium, Wangia profunda SM-A87, and an anionic surfactant, sodium fatty alcohol polyoxyethylene ether sulfate (AES), were studied. Both the foamability and foam stability of the EPS/AES solutions are considerably higher than those of single AES solutions, even at very low AES concentrations, although pure EPS solutions cannot foam. The improved foamability and foam stability arise from the formation of the EPS/AES complex via hydrogen bonds at the interfaces. The synergism between the EPS and AES decreases the surface tension, increases the interfacial elasticity and water-carrying capacity, and suppresses the coalescence and collapse of the foams. The EPS/AES foams are more salt-resistant than the AES foams. This work provides not only a new eco-friendly foam with great potential for use in enhanced oil recovery and health-care products but also useful guidance for designing other environmentally friendly foam systems that exhibit high performance.


Assuntos
Éteres/química , Álcoois Graxos/química , Polietilenoglicóis/química , Polissacarídeos Bacterianos/química , Tensoativos/química , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Reologia , Soluções/química , Tensão Superficial , Viscosidade , Água/química
10.
Talanta ; 141: 300-6, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25966418

RESUMO

This paper presents a new electrochemical DNA biosensor constructed using a substrate electrode composed of a novel nanocomposite material prepared using gold nanoparticles (Au-NPs) and multiwalled carbon nanotubes (MWCNTs) and further modified with an Au electrode (AuE), which was used as the substrate electrode. A single-stranded DNA (ssDNA) probe was immobilized on the Au-NPs/CS-MWCNTs/AuE electrode by means of facile gold-thiol affinity, which resulted in hybridization with the target ssDNA sequence. Hybridization reactions were assessed by using the reduction peak current of methylene blue (MB) as an electrochemical indicator. The advantages of the nanomaterials were found to include high surface area, favorable electronic properties, and strong electrocatalytic activity. The amount of ssDNA adsorbed on the electrode surface was increased and the electrochemical response of MB accelerated. The differential pulse voltammetric responses of MB were in line with the specific target ssDNA sequence within the concentration range 1.0×10(-15)-1.0×10(-8)M with the detection limit 3.3×10(-16)M (3σ). In the colony forming unit (CFU) we were able to detect 10CFU mL(-1)of Staphylococcus aureus in the tap water, achieving good discrimination ability between one- and three-base mismatched ssDNA sequences. The polymerase chain reaction (PCR) amplification products of S. aureus nuc gene sequence were also detected with satisfactory results.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Azul de Metileno , Staphylococcus aureus/genética , Animais , Proteínas de Bactérias/genética , Técnicas Biossensoriais/instrumentação , Calibragem , Técnicas Eletroquímicas/instrumentação , Eletrodos , Desenho de Equipamento , Ouro/química , Ácidos Nucleicos Imobilizados , Azul de Metileno/química , Nuclease do Micrococo/genética , Leite/microbiologia , Nanopartículas/química , Nanotubos de Carbono , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Microbiologia da Água
11.
Biosens Bioelectron ; 70: 447-54, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25863342

RESUMO

In this study, a novel and simple cell-based electrochemical biosensor was developed to assess the individual and combined toxicity of deoxynivalenol (DON) and zearalenone (ZEN) on BEL-7402 cells. The sensor was fabricated by modification with AuNPs, p-aminothiophenol, and folic acid in succession. The BEL-7402 cells which had a good activity were adhered on the electrode through the high affinity between the folate receptor and folic acid selectivity. We used the collagen to maintain the cell adhesion and viability. Electrochemical impedance spectroscopy (EIS) was developed to evaluate the individual and combined toxicity of DON and ZEN. Our results indicate that DON and ZEN caused a marked decrease in the cell viability in a dose-dependent manner. The value of electrochemical impedance spectroscopy decreased with the concentration of DON and ZEN in range of 0.1-20, 0.1-50 µg/ml with the detection limit as 0.03, 0.05 µg/ml, respectively, the IC50 for DON and ZEN as obtained by the proposed electrochemical method were 7.1 µg/ml and 24.6 µg/ml, respectively, and the combination of two mycotoxins appears to generate an additive response. The electrochemical cytotoxicity evaluation result was confirmed by biological assays. Compared to conventional methods, this electrochemical test is inexpensive, highly sensitive, and fast to respond, with long-term monitoring and real-time measurements. The proposed method provides a new avenue for evaluating the toxicity of mycotoxins.


Assuntos
Bioensaio/instrumentação , Sobrevivência Celular/efeitos dos fármacos , Espectroscopia Dielétrica/instrumentação , Testes de Toxicidade/instrumentação , Tricotecenos/toxicidade , Zearalenona/toxicidade , Linhagem Celular Tumoral , Combinação de Medicamentos , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Dose Letal Mediana , Micotoxinas/administração & dosagem , Micotoxinas/uso terapêutico , Neoplasias Experimentais , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tricotecenos/administração & dosagem , Zearalenona/administração & dosagem
12.
J Hazard Mater ; 286: 466-73, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25603296

RESUMO

In recent years, aqueous foam was known as an efficient technique with high potential on being used to remove heavy metal ions from the polluted water, not only because of the low cost, simple operation, but also ascribed to the high removal efficiency of trace heavy metal ions and would not cause secondary pollution to the environment. In this paper, the removal of Cd(2+) from aqueous solution by aqueous foam stabilized by a kind of novel anionic-nonionic surfactant sodium trideceth-4 carboxylate (AEC) was investigated. The effect of conditions such as surfactant/metal ions molar ratio, surfactant concentration on the removal efficiency was studied. In large concentration range of surfactant, the removal rate was higher than 90%, and could reach up to 99.8% under the optimum conditions. The Zeta potential of gas bubbles in the AEC solutions was determined to verify the combination between the negative charged group heads of surfactant molecules and heavy metal ions, and isothermal titration calorimeter (ITC) determination was utilized to demonstrate the interaction, which helped to understand the mechanisms more clearly.


Assuntos
Cádmio/química , Ácidos Carboxílicos/química , Tensoativos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
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