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1.
Sensors (Basel) ; 24(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38732816

RESUMO

Target detection technology based on unmanned aerial vehicle (UAV)-derived aerial imagery has been widely applied in the field of forest fire patrol and rescue. However, due to the specificity of UAV platforms, there are still significant issues to be resolved such as severe omission, low detection accuracy, and poor early warning effectiveness. In light of these issues, this paper proposes an improved YOLOX network for the rapid detection of forest fires in images captured by UAVs. Firstly, to enhance the network's feature-extraction capability in complex fire environments, a multi-level-feature-extraction structure, CSP-ML, is designed to improve the algorithm's detection accuracy for small-target fire areas. Additionally, a CBAM attention mechanism is embedded in the neck network to reduce interference caused by background noise and irrelevant information. Secondly, an adaptive-feature-extraction module is introduced in the YOLOX network's feature fusion part to prevent the loss of important feature information during the fusion process, thus enhancing the network's feature-learning capability. Lastly, the CIoU loss function is used to replace the original loss function, to address issues such as excessive optimization of negative samples and poor gradient-descent direction, thereby strengthening the network's effective recognition of positive samples. Experimental results show that the improved YOLOX network has better detection performance, with mAP@50 and mAP@50_95 increasing by 6.4% and 2.17%, respectively, compared to the traditional YOLOX network. In multi-target flame and small-target flame scenarios, the improved YOLO model achieved a mAP of 96.3%, outperforming deep learning algorithms such as FasterRCNN, SSD, and YOLOv5 by 33.5%, 7.7%, and 7%, respectively. It has a lower omission rate and higher detection accuracy, and it is capable of handling small-target detection tasks in complex fire environments. This can provide support for UAV patrol and rescue applications from a high-altitude perspective.

2.
PLoS Pathog ; 17(6): e1009616, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34111220

RESUMO

The final stage of Ebola virus (EBOV) replication is budding from host cells, where the matrix protein VP40 is essential for driving this process. Many post-translational modifications such as ubiquitination are involved in VP40 egress, but acetylation has not been studied yet. Here, we characterize NEDD4 is acetylated at a conserved Lys667 mediated by the acetyltransferase P300 which drives VP40 egress process. Importantly, P300-mediated NEDD4 acetylation promotes NEDD4-VP40 interaction which enhances NEDD4 E3 ligase activity and is essential for the activation of VP40 ubiquitination and subsequent egress. Finally, we find that Zaire ebolavirus production is dramatically reduced in P300 knockout cell lines, suggesting that P300-mediated NEDD4 acetylation may have a physiological effect on Ebola virus life cycle. Thus, our study identifies an acetylation-dependent regulatory mechanism that governs VP40 ubiquitination and provides insights into how acetylation controls EBOV VP40 egress.


Assuntos
Doença pelo Vírus Ebola/metabolismo , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Proteínas da Matriz Viral/metabolismo , Liberação de Vírus/fisiologia , Fatores de Transcrição de p300-CBP/metabolismo , Acetilação , Linhagem Celular , Ebolavirus/fisiologia , Humanos
3.
Arch Gynecol Obstet ; 297(6): 1525-1532, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29610946

RESUMO

PURPOSE: Little is known about ZNF84 gene. This study aims to investigate ZNF84 expression in cervical cancer (CC) and the effects of ZNF84 on CC. MATERIALS AND METHODS: Cervical cancer tissue specimens were collected from The First People's Hospital of Foshan. ZNF84 and Akt expression were detected by immunohistochemistry. The influence of ZNF84 on cell proliferation was detected by CCK-8 kits. The effects of ZNF84 on Akt protein and mRNA expression were detected by western blotting and qPCR, respectively. RESULTS: High expression of ZNF84 protein (80.0%) was detected within CC tissues while negative expression was found in normal cervical tissues. ZNF84 was specifically associated with tumor size (p = 0.018) and negatively associated with other indicators. Further, in squamous cell carcinoma, ZNF84 was associated with both TNM staging (p = 0.041) and tumor size (p = 0.041). In vitro, we used shZNF84 to inhibit the mRNA and protein expression of ZNF84, and showed marked inhibition of cancer cell proliferation by shZNF84. Furthermore, inhibition of ZNF84 down-regulated Akt. Ly294002 (an Akt inhibitor) decreased the cell inhibition ability of shZNF84, indicating the involvement of Akt. Finally, the relationship between ZNF84 and Akt in vivo showed positive correlation (p = 0.023). CONCLUSION: ZNF84 expression was increased in CC tissues and associated with tumor size. ZNF84 promoted cell proliferation which might involve Akt signal.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias do Colo do Útero/metabolismo , Western Blotting , Carcinoma de Células Escamosas/patologia , Proliferação de Células , Regulação para Baixo , Feminino , Humanos , Imuno-Histoquímica , Estadiamento de Neoplasias , Proteína Oncogênica v-akt , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas c-akt/genética , RNA Mensageiro/genética , Neoplasias do Colo do Útero/patologia
4.
Environ Pollut ; 253: 302-311, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31323613

RESUMO

Fomesafen, a long-lived protoporphyrinogen-oxidase inhibitor, specially developed for post-emergence control of broad-leaf weeds, is used widely in soybean fields in northern China (Dayan and Duke, 2010). The impact of fomesafen on microbial communities in rhizosphere soils, however, is unknown. In this study we examined fomesafen degradation as well as its effects in the rhizosphere of soybean plants grown in a greenhouse. Fomesafen had shorter half-life in rhizosphere soil than previously reported for bulk soil from the same location (87 vs 120 days). The enzyme activity of soil extracts and the microbial community composition of 16S rRNA genes (16S) amplified from soil DNA were also investigated. Although not immediately apparent, both the high (37.5 mg kg-1) and low (18.75 mg kg-1) doses of fomesafen significantly decreased urease and invertase activities in the rhizosphere soil from days 30 and 45 respectively until the end of the experiment (90 days). Analysis of 16S amplicons demonstrated that fomesafen had a dose dependent effect, decreasing alpha diversity and altering beta diversity. Significant phylum level decreases were observed in five of the ten phyla that were most abundant in the control. Proteobacteria was the only phylum whose relative abundance increased in the presence of fomesafen, driven by increases in the genera Methylophilacaea, Dyella, and Sphingomonas. The functional implications of changes in 16S abundance as predicted using PICRUSt suggested that fomesafen enriched for enzymes involved in xenobiotic metabolism and detoxification (cytochrome P450s and glutathione metabolism). Our data suggest that, despite being degraded more rapidly in the rhizosphere than in bulk soil, fomesafen had long-lasting functional impacts on the soil microbial community.


Assuntos
Benzamidas/toxicidade , Inibidores Enzimáticos/toxicidade , Rizosfera , Microbiologia do Solo , Poluentes do Solo/toxicidade , Bactérias/efeitos dos fármacos , China , Microbiota , Proteobactérias/genética , RNA Ribossômico 16S/genética , Solo , Poluentes do Solo/análise , Glycine max
5.
Dalton Trans ; 47(35): 12243-12252, 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30106408

RESUMO

A series of steric phenylpyridazine based homoleptic iridium(iii) complexes (1-3) have been synthesized with novel one-pot methods. Single X-ray structural analyses are conducted on complexes 1 and 2 to reveal their coordination arrangement. These complexes exhibit a very strong green phosphorescence emission with high quantum yields of over 64%. The relationship between photophysical properties and the substituent nature of the complexes is discussed by density functional theory (DFT) and time-dependent DFT. Self-quenching is significantly reduced for these complexes in solid even at very high concentrations because the sterically hindered bicyclo [2.2.2] oct-2-ene and m-substituted CF3 spacers in the phosphor molecules lead to minimum bimolecular interactions. Accordingly, the electroluminescence device based on complex 3 exhibits a maximum luminous efficiency of 64.1 cd A-1 with a high EQE of 25.2% at a high doping concentration of 15 wt%. Meanwhile, when neat 3 was adopted as the emitting layer, the non-doped green device gives a state-of-the-art EQE as high as 15.2% (40.1 cd A-1) along with CIE coordinates of (0.346, 0.599).

6.
Nanoscale Res Lett ; 12(1): 588, 2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29124414

RESUMO

In recent years, BiVO4 has drawn much attention as a novel photocatalyst given its excellent ability to absorb visible light. This work reports the development of Ag-modified BiV1-xMoxO4 composites through a facile hydrothermal synthesis with the subsequent photoinduced reduction of Ag+ at almost neutral pH conditions. Metallic Ag nanoparticles were deposited on the (040) facet of Mo-doped BiVO4 powders. The crystal structure and morphology of the as-prepared samples were studied by XRD and SEM analyses. Moreover, the photocatalytic performance of BiVO4, Ag/BiVO4, and Ag-modified BiV1-xMoxO4 were evaluated by the degradation of rhodamine B (RhB). The Ag/BiV0.9925Mo0.0075O4 composite exhibited the most efficient photocatalytic performance. The present work provides greater insight into the application of BiVO4 in the field of photocatalysis.

7.
J Orthop Surg Res ; 10: 92, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-26063220

RESUMO

BACKGROUND: The aim of this study was to analyze the pattern and types of sensory nerve endings in ankle collateral ligaments using histological techniques, in order to observe the morphology and distribution of mechanoreceptors in the collateral ligaments of cadaver ankle joint, and to provide the morphological evidence for the role of the ligament in joint sensory function. METHODS: Twelve lateral collateral ligaments including anterior talofibular ligament (ATFL; n = 6), posterior talofibular ligament (PTFL; n = 6), and calcaneofibular ligament (CFL; n = 6) were harvested from six fresh frozen cadavers. The ligaments were embedded in paraffin, sectioned at 4 µm, and then stained using a modified gold-chloride staining methods. The collateral ligament was divided into three segments: proximal, middle, and distal segments. Fifty-four ATFL slides, 90 PTFL slides, and 108 CFL slides were analyzed. Mechanoreceptors were classified based on Freemen and Wyke's classification. Mechanoreceptor distribution was analyzed statistically. One-way ANOVA (postHoc LSD) was used for statistical analysis. RESULTS: All the four typical types of nerve endings (the Ruffini corpuscles, Pacinian corpuscles, Golgi tendon organs, and free nerve endings) were identified in these ligaments. Pacinian corpuscles were the predominant in all four complexes. More mechanoreceptors were found in synovial membrane near both ends of the ligaments attached to the bone. No statistical differences were found in the amount of mechanoreceptors among distal, middle, and proximal parts of the ligaments. CONCLUSIONS: The four typical types of mechanoreceptors were all identified in the collateral ligaments of the human ankle. Pacinian corpuscles were the predominant in all four complexes. This indicates that the main function of ankle collateral ligaments is to sense joint speeds in motions.


Assuntos
Ligamentos Laterais do Tornozelo/citologia , Mecanorreceptores/citologia , Adulto , Feminino , Compostos de Ouro , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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