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1.
Adv Colloid Interface Sci ; 332: 103271, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39146581

RESUMEN

With the rapid development of information and communication industries, the usage of electromagnetic waves has caused the hazard of human health and misfunction of devices. The adsorption and shielding of electromagnetic waves have been achieved in various materials. The unique adjustable spatial structure makes metal-organic frameworks (MOFs) promising for electromagnetic shielding and adsorbing. As MOFs research advances, various large-scale MOF-based materials have been developed. For instance, MOFs spatial structure has been expanded from 2D to 3D to load more ligands. Progress in synthetic methods for MOFs and their derivatives is advancing, with priority on large-scale preparation and green synthesis. This review summarizes the methods for synthesizing MOFs and their derivatives, and explores the effects of MOFs spatial structure on electromagnetic interference (EMI) shielding and electromagnetic wave absorption capabilities. At the same time, detailed examples are used to focus on the applications of five different MOFs composites in electromagnetic shielding and electromagnetic wave absorption. Finally, the current challenges and prospects of MOFs in the electromagnetic field are introduced, providing a useful reference for the preparation and design of MOFs and their composites for electromagnetic wave processing applications.

2.
Insects ; 15(4)2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38667426

RESUMEN

Saliva plays a crucial role in shaping the compatibility of piercing-sucking insects with their host plants. Understanding the complex composition of leafhopper saliva is important for developing effective and eco-friendly control strategies for the tea green leafhopper, Empoasca flavescens Fabrecius, a major piercing-sucking pest in Chinese tea plantations. This study explored the saliva proteins of tea green leafhopper adults using a custom collection device, consisting of two layers of Parafilm stretched over a sucrose diet. A total of 152 proteins were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS) following the filter-aided sample preparation (FASP). These proteins were categorized into six groups based on their functions, including enzymes, transport proteins, regulatory proteins, cell structure proteins, other proteins, and unknown proteins. Bioinformatics analyses predicted 16 secreted proteins, which were successfully cloned and transcriptionally analyzed across various tissues and developmental stages. Genes encoding putative salivary secretory proteins, including Efmucin1, EfOBP1, EfOBP2, EfOBP3, Efmucin2, low-density lipoprotein receptor-related protein (EfLRP), EFVg1, and EFVg2, exhibited high expressions in salivary gland (SG) tissues and feeding-associated expressions at different developmental stages. These findings shed light on the potential elicitors or effectors mediating the leafhopper feeding and defense responses in tea plants, providing insights into the coevolution of tea plants and leafhoppers. The study's conclusions open avenues for the development of innovative leafhopper control technologies that reduce the reliance on pesticides in the tea industry.

3.
Sci Total Environ ; 924: 171657, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38490413

RESUMEN

Global occurrences of foodborne disease outbreaks have been documented, involving fresh agricultural produce contaminated by various pathogens. This contamination can occur at any point in the supply chain. However, studies on the prevalence of total coliforms, Salmonella and microbial diversity in vegetable and associated environments are limited. This study aimed to assess 1) the number of total coliforms (n = 299) and diversity of microbial communities (n = 52); 2) the prevalence, antibiotic susceptibility, genomic characteristics, and potential transmission relationships of Salmonella in soil-irrigation water-vegetable system (n = 506). Overall, 84.28 % samples were positive to total coliforms, with most frequently detected in soil (100 %), followed by irrigation water (79.26 %) and vegetables (62.00 %). A seasonal trend in coliform prevalence was observed, with significantly higher levels in summer (P < 0.05). Detection rates of Salmonella in soil, vegetable and irrigation water were 2.21 %, 4.74 % and 9.40 %. Fourteen serotypes and sequence types (STs) were respectively annotated in 56 Salmonella isolates, ST13 S. Agona (30.36 %, 17/56), ST469 S. Rissen (25.00 %, 14/56), and ST36 S. Typhimurium (12.50 %, 7/56) were dominant serotypes and STs. Thirty-one (55.36 %) isolates were multi-drug resistant, and the resistance was most frequently found to ampicillin (55.36 %, 31/56), followed by to sulfamethoxazole (51.79 %, 29/56) and tetracycline (50.00 %, 28/56). The genomic characteristics and antibiotic resistance patterns of Salmonella isolates from soil, vegetables, and irrigation water within a coherent geographical locale exhibited remarkable similarities, indicating Salmonella may be transmitted among these environments or have a common source of contamination. Microbial alpha diversity indices in soil were significantly higher (P < 0.05) than that in vegetable and irrigation water. The microbial phylum in irrigation water covered that in the vegetable, demonstrating a significant overlap in the microbial communities between the vegetables and the irrigation water.


Asunto(s)
Suelo , Verduras , Riego Agrícola , Salmonella , Antibacterianos , Agua , Pruebas de Sensibilidad Microbiana
4.
Int J Food Microbiol ; 414: 110629, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38368793

RESUMEN

The rise of antibiotic resistance in Escherichia coli has become a major global public health concern. While there is extensive research on antibiotic-resistant E. coli from human and animal sources, studies on vegetables and their environments are limited. This study investigated the prevalence and characteristics of ciprofloxacin-resistant (CIPR) E. coli in 13 types of edible raw vegetables, along with their irrigation water and soil in Shaanxi, China. Of 349 samples collected (157 vegetables, 59 water, and 133 soil), a total of 48 positive samples were detected, with one CIPRE. coli strain isolated from each sample being selected for further analyses. A striking observation was its high prevalence in irrigation water at 44.1 %, markedly exceeding that in vegetables (12.0 %) and soil (4.5 %). The susceptibility of Forty-eight CIPRE. coli isolates was evaluated using the disc diffusion method for 18 different antibiotics, all these isolates were not only resistant to the tested fluoroquinolones antibiotics (levofloxacin, nalidixic acid), but also displayed a multi-drug resistance (MDR) pattern. Twenty-eight (58.3 %) of 48 CIPRE. coli isolates exhibited extended spectrum ß-lactamases (ESBLs) (CIPR-ESBLs) producing phenotype. Subsequently, whole-genome sequencing was performed on these 28 isolates. We identified 12 serotypes and STs each, with O101: H9 (35.7 %, 10/28) and ST10 (21.4 %, 6/28) being the most common. Further classification placed these isolates into five phylogenetic groups: A (57.1 %, 16/28), B1 (32.1 %, 9/28), D (3.6 %, 1/28), B2 (3.6 %,1/28), and F (3.6 %,1/28). Notelly, Identical ST types, serotypes and phylogroups were found in certain CIPR-ESBLs-producing E. coli from both vegetables and adjacent irrigation water. Genomic analysis of the 28 CIPR-ESBLs-producing E. coli isolates unveiled 73 resistance genes, associated with 13 amino acid mutations in resistance-determining regions (QRDRs) and resistance to 12 types of antibiotics. Each isolate was confirmed to carry both ESBLs and fluoroquinolone resistance genes, with the Ser83Ala mutation in GyrA (96.4 %, 27/28) being the most prevalent. A detailed analysis of Mobile Genetic Elements (MGEs) revealed that IncFIB and IncFII plasmid subtypes were most prevalent in 60.7 % and 67.9 % of isolates, respectively, with 75 % containing over 10 insertion sequences (IS) each. Furthermore, we observed that certain ESBL and PMQR genes were located on plasmids or in proximity to insertion sequences. In conclusion, our research highlights the widespread presence of CIPRE. coli in irrigation water and thoroughly examines the genetic characteristics of CIPR-ESBLs-producing E. coli strains, underlining the need for ongoing monitoring and management to reduce multidrug-resistant bacteria in vegetables and their environment.


Asunto(s)
Ciprofloxacina , Infecciones por Escherichia coli , Animales , Humanos , Ciprofloxacina/farmacología , Escherichia coli , Verduras/microbiología , Elementos Transponibles de ADN , Filogenia , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Antibacterianos/farmacología , Antibacterianos/metabolismo , Infecciones por Escherichia coli/microbiología , Fluoroquinolonas , Genómica , Agua/metabolismo
5.
Comput Biol Med ; 170: 107983, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38286104

RESUMEN

Magnetic resonance (MR) image-guided radiotherapy is widely used in the treatment planning of malignant tumors, and MR-only radiotherapy, a representative of this technique, requires synthetic computed tomography (sCT) images for effective radiotherapy planning. Convolutional neural networks (CNN) have shown remarkable performance in generating sCT images. However, CNN-based models tend to synthesize more low-frequency components and the pixel-wise loss function usually used to optimize the model can result in blurred images. To address these problems, a frequency attention conditional generative adversarial network (FACGAN) is proposed in this paper. Specifically, a frequency cycle generative model (FCGM) is designed to enhance the inter-mapping between MR and CT and extract more rich tissue structure information. Additionally, a residual frequency channel attention (RFCA) module is proposed and incorporated into the generator to enhance its ability in perceiving the high-frequency image features. Finally, high-frequency loss (HFL) and cycle consistency high-frequency loss (CHFL) are added to the objective function to optimize the model training. The effectiveness of the proposed model is validated on pelvic and brain datasets and compared with state-of-the-art deep learning models. The results show that FACGAN produces higher-quality sCT images while retaining clearer and richer high-frequency texture information.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Tomografía Computarizada por Rayos X , Procesamiento de Imagen Asistido por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Redes Neurales de la Computación , Imagen por Resonancia Magnética/métodos , Planificación de la Radioterapia Asistida por Computador/métodos
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