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小白菜是中国种植面积较广、深受大众喜爱的蔬菜,但真实菜地环境中虫害往往出现在叶片的特定区域,且受环境因素如光照和背景干扰较大,影响对其的智能检测。为提高小白菜虫害的检测效率和准确率,该研究提出一种基于YOLOv5s网络框架改进的YOLOPC小白菜虫害识别模型。首先,引入CBAM(Convolutional Block Attention Module)注意力机制,将其放在CBS(卷积层Convolution+归一化层Batch normalization+激活函数层SILU)的输入端构成CBAM-CBS的结构,动态调整特征图中各个通道和空间位置的权重;使用上采样和1×1卷积操作来调整特征图的尺寸和通道数,实现不同层次特征的融合,增强模型的特征表示能力。同时,改进损失函数,使其更适合边界框回归的准确性需求;利用空洞卷积的优势提高网络的感受野范围,使模型能够更好地理解图像的上下文信息。试验结果表明,与改进前的YOLOv5s模型相比,YOLOPC模型对小白菜小菜蛾和潜叶蝇虫害检测的平均精度(mean Average Precision, mAP)达到91.40%,提高了12.9个百分点;每秒传输帧数(Frame Per Second, FPS)为58.82帧/s,增加了11.2帧/s,增加幅度达23.53个百分点;参数量仅为14.4 MB,降低了25.78个百分点。与经典的目标检测算法SSD、Faster R-CNN、YOLOv3、YOLOv7和YOLOv8相比,YOLOPC模型的平均精度分别高出20.1、24.6、14、13.4和13.3个百分点,此外,其准确率、召回率、帧速率和参数量均展现出显著优势。该模型可为复杂背景下小白菜虫害的快速准确检测提供技术支持。 相似文献
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Rebecca Windsor Samuel Stewart Jessica Schmidt Mario Mosqueda Ignazio Piras Stefan M. Keller Briana Steinmetz Dori L. Borjesson Matthew Huentelman Chand Khanna 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2022,36(4):1382
BackgroundNecrotizing meningoencephalitis (NME) in the pug dogs is a fatal neuroinflammatory disease associated with rapid progression and poor response to conventional immunosuppressive therapy. Diagnosis is typically made after severe neurological abnormalities have manifested.Hypothesis/ObjectivePug dogs at genetic risk for NME might manifest neurological abnormalities before developing pathognomonic clinical signs of NME.AnimalsThirty‐six pug dogs less than 4 years of age asymptomatic for NME.MethodsProspective observational cohort study with germline genome‐wide genotyping. Neurological examinations were performed 4 weeks apart to document reproducible findings of central nervous system disease. Magnetic resonance imaging, cerebrospinal fluid analysis, and testing for infectious diseases were performed in all pugs with reproducible abnormalities detected on neurological examination.ResultsThe overall risk allele frequency in this cohort was 40%; 5 (14%) dogs were high risk, 19 (53%) dogs were medium risk, and 12 (33%) dogs were low genetic risk for NME. Reproducible abnormalities detected on neurological examination were identified in 8/24 (33%) genetically at‐risk dogs and 0/12 (0%) low risk dogs. Clinical abnormalities included multifocal spinal pain in 8/8, reduced menace response in 5/8, and lateralizing postural reaction deficits in 5/8 pugs. There was a strong association between genotype risk and the presence of this clinical phenotype (P = .03).Conclusions and Clinical ImportanceOur findings suggest the presence of a novel early clinical phenotype of NME in apparently asymptomatic genetically at‐risk pugs which might be used to plan early diagnostic and therapeutic clinical trials. 相似文献
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AIM: To demonstrate the susceptibility of cell apoptosis varies during the progress of cell malignant transformation from human being in vitro. METHODS: A SV40T-transfected human bronchial epithelial immortalized cell line (called M) was selected in this work, which has acquired some characteristics of malignant transformation at the later passage. The alterations of apoptosis and bcl-2, P53 genes between early and later passage of M cells were investigated by means of TDT labeling in situ, chromosome FISH, RNA and protein testing, etc. RESULTS: Incidence of apoptosis induced by cis-platin was significantly lower in later than in early passages of M. Levels of bcl-2 mRNA and protein in later passages were higher than early passages of M, and overexpression of bcl-2 was accumulated following the development of cellular malignancy. P53 protein level was as high in early as in later passages. CONCLUSION: Overexpression of bcl-2 decreases the cellular sensitivity to apoptotic inductors plays an important role during progress of carcinogenesis in human bronchial epithelial cancers. The inactivation of P53 protein in the SV40-T transfected M cell line may be one of reasons of bcl-2 overexpression, but not associated with the accumulation of bcl-2 expressed level during cell transformation. 相似文献
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CHENG Shao-bing TAN Dun-yong CHEN Xiao-lin YANG Hao-zhuang ZHANG Sui-mei YAN Liang 《园艺学报》2000,16(5):397-400
AIM and METHODS:To clarify the role of inducible nitric oxide synthase (iNOS) in the regulation of blood pressure,in the present study, we examined the effect of aminoguanidine (AG), a selective inhibitor of iNOS on the hemodinamical response of Dahl salt-sensitive (DS) and Dahl salt-resistant (DR) rats to low (0.3%) or high (8%) sodium chloride (NaCl) infusion by chronical in vivo hemodynamic experiment, and the effect of NaCl or NaCl plus AG infusion on urinary nitrate (NO3)/nitrite (NO2), the end product of nitric oxide (NO), excretion by Greiss Reaction. Furthermore, NOS activity assay was also carried out to probe the effect of NaCl and AG on calcium-dependent or independent NOS activity in renal tissue. RESULTS:1. High or low NaCl-infused DR rats and low NaCl-infused DS rats have no hemodinamical response to AG, however, the hypertensive effect of high NaCl (8%) infusion on DS rats were greatly amplified by co-infusion of AG. 2. Administration of high NaCl significantly elevated the iNOS activity of renal tissue, and greatly increased urinary NO3/NO2 excretion. CONCLUSION:Inducible NOS is an important modulator of arterial pressure, especially in case of higher blood pressure. 相似文献
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AIM: To investigate the effects of oxidized high-density lipoprotein (oxHDL) on membrane fluidity and the expression of lymphocyte function associated antigen(LFA-1) of monocyte. METHODS: The membrane fluidity of THP-1 cells was assayed by fluorescence anisotropy with DPH (1,6-dipheny-1,3,5-hexatriene), a fluorescent probe; The LFA-1 expression on THP-1 cells were assayed by flow cytometry with indirect immunofluorescence.RESULTS: The membrane fluidity of THP-1 cells was reduced by 45% and 52% respectively (P<0.01) after incubation with 100 μg protein/mL oxHDL and oxLDL for 20 h; oxHDL could stimulated the expression of LFA-1 on THP-1 cells, the positive cell rate and mean fluoresence intensity (MFI) increased by 39% and 45% respectively versus control group (P<0.01) after incubation with cells for 24 h. CONCLUSIONS: By increasing the expression of LFA-1 on monocyte, oxHDL can promote the monocyte-endothelium adhesion; oxHDL also can reduce the membrane fluidity of monocyte, that will limit the returning of monocytes from subendothelium back to the circulation. This suggested that oxHDL may play an important role in atherogenesis. 相似文献
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AIM: To evaluate the association between apolipoprotein E(apoE) gene polymorphism and sporadic Alzheimer's disease (AD). METHOD: A case-control study was undertaken detecting the polymorphism of apoE by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP).RESULTS:(1)The frequencies of 3/4 genotype and 4 al ele in AD were significant ly higher than that in age-matched controls(P<0.05).(2)The frequency of G/G genotype for apoE IE1 in AD was significantly higher than that in age-mat ched control(P<0.05).(3)The apoE 4 al ele was associated with a tripling of the risk for AD compared with no 4 allele(odd ratio 2.932, 95%CI 1.379~6.226);Homozygosity of the G allele in IE1 was associated with adoubling of the risk for AD compared with the G/C and C/C genotypes(odd rat io 2.223, 95%CI 1.075~4.599).However, the IE1 G al ele is also closely associated with apoE 4.When the sample was split on the basis of apo Egenotype, the associat ion between IE1 G/G genotype and AD was no longer statistically significant.CONCLUSION: ApoE ε4 was a risk factor of AD, and the apparent association between IE1 G/G and AD is a consequence of the association between the ε4 and IE1 G/G genotype. 相似文献