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1.
Comput Intell Neurosci ; 2022: 4155461, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35669653

RESUMEN

Face age estimation has been widely used in video surveillance, human-computer interaction, market analysis, image processing analysis, and many fields. There are several problems that need to be solved in image-based face age estimation: (1) redundant information of age characteristics; (2) limitations of age estimation methods in solving age estimation problems; (3) the performance of age estimation models being also affected by gender factors. This paper proposes CA-XTree network. Firstly, features are extracted through the convolution layer and then combined with the local channel attention module to strengthen the ability of age feature information interaction between different channels. Secondly, extracted features are inputted into the recommendation score function to obtain the recommendation score, by combining the recommendation score with the gradient ascending regression tree. The lifting tree processed loss function is the mean square loss function, and the final age value is obtained by the leaf node. This paper improves state of the art for image classification on MORPH and CACD datasets. The advantage of our model is that it is easy to implement and has no excess memory overhead. In the age dataset CACD, the mean absolute error (MAE) has reached 4.535 and cumulative score (CS) has reached 63.53%, respectively.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Atención , Cara , Humanos , Solución de Problemas
2.
Comput Intell Neurosci ; 2022: 3798060, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35498206

RESUMEN

Occlusion pedestrian detection is an important and difficult task in pedestrian detection. At present, the main method to deal with occlusion pedestrian detection usually adopts pedestrian parts or human body relationship methods. However, in the scene of crowd occlusion or severe pedestrian occlusion, only small parts of the body can be used for detection. Pedestrian parts or human body relationship methods cannot effectively address these issues. In view of the above problems, this paper abandoned the occlusion processing method of pedestrian parts or human body relationship. Considering that it is difficult to establish the relationship between parts and key points. The scale of visible parts of the occlusion pedestrian is small, and the scale of no occlusion pedestrian and occlusion pedestrian in the same picture is different. A multiscale feature attention fusion network named parallel feature fusion with CBAM (PFF-CB) is proposed for occlusion pedestrian detection. Feature information of different scales can be integrated effectively in the PFF-CB module. PFF-CB module uses a convolutional block attention module (CBAM) to enhance the important feature information in space and channel. A parallel feature fusion module based on FPN is used to enhance key features. The performance of the proposed module was tested on two common data sets of occlusion pedestrians with different occlusion types. The results show that the PFF-CB module makes a good performance in occlusion pedestrian detection tasks.


Asunto(s)
Peatones , Humanos
3.
J Pharm Biomed Anal ; 212: 114609, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35158187

RESUMEN

An anti-phenolphthalein monoclonal antibody (mAb) was prepared based on the N,N'-Carbonyldiimidazole (CDI) method through phenolphthalein conjugated with proteins. Indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and colloidal gold-based immunochromatographic assay (ICA) methods were used to determine phenolphthalein in slimming products. A standard curve was established, and the IC50 and limit of detection of ic-ELISA were 0.95 and 0.10 ng/mL with a linear detection range of 0.27-3.37 ng/mL. The developed ICA was used to detect phenolphthalein in tablets, capsules, and slimming tea samples with visual limit of detection values of 10 µg/kg, and cut-off values of 200 µg/kg. The results indicated that these two methods could be used to quickly detect phenolphthalein in slimming products.


Asunto(s)
Oro Coloide , Fenolftaleína , Cromatografía de Afinidad , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoensayo/métodos
4.
Food Chem ; 379: 132131, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35065500

RESUMEN

Oxadixyl is a systemic phenylamide fungicide, used to prevent and control disease caused by phytophthora and downy mildew in a variety of cash crops. In this study, a hapten of oxadixyl was designed and used to prepare a highly specific and sensitive anti-oxadixyl monoclonal antibody (mAb) with a 50% inhibition concentration of 3.68 ng/mL. An immunochromatographic assay (ICA) was developed for screening of oxadixyl residues in cucumber, tomato and wine. The ICA strip provided a visible limit of detection (vLOD) of 1 ng/g and a cut-off value of 20 ng/g in cucumbers and tomatoes and displayed a vLOD of 5 ng/mL and a cut-off value of 100 ng/mL in wine. The calculated limit of detection (cLOD) values of the ICA were 1.45 and 0.55 ng/g for cucumbers and tomatoes and 2.11 ng/mL for wine. The ICA gave recovery rates of 95.4-106.0% for cucumber samples, 96.4-99.5% for tomato samples and 93.0-97.4% for wine samples. Moreover, the test results provided by the ICA were highly consistent with those of LC/MS. These results and data indicated that the ICA was an effective and practical method for rapid and high-throughput detection of oxadixyl residues in cucumber, tomato, wine and other food samples.


Asunto(s)
Cucumis sativus , Solanum lycopersicum , Vino , Acetamidas , Cromatografía de Afinidad , Inmunoensayo , Límite de Detección , Oxazoles
5.
Food Chem ; 370: 131284, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34788953

RESUMEN

Propamocarb is a carbamate fungicide used to control Phytophthora disease. Frequent and large-scale use of propamocarb means that it poses a potential threat to the health of consumers. Monoclonal antibodies against propamocarb were prepared using a hapten of propamocarb that was generated by introducing a benzene ring and a carboxyl group into the structure of propamocarb. A lateral flow immunoassay strip was developed for the detection of propamocarb in tomato and cucumber samples using the gold nanoparticle-labeled antibody. The immunoassay strip was found to provide a visible limit of detection was 5 ng/g and the cut-off value was 250 ng/g for propamocarb in food samples. For quantitative analysis, the calculated limits of detection (LODs) of the immunoassay strip were 1.43 ng/g and 0.44 ng/g in cucumber and tomato, respectively. Using the immunoassay strip, the average recoveries ranged from 95.5 ± 5.4% to 108.8 ± 6.8%, with CVs of 3.1-6.2% for the cucumber, and the average recoveries were 95.1 ± 6.5%-111.9 ± 4.2%, with CVs ranging from 3.7% to 6.8% for tomato samples. All the results demonstrated that the immunoassay strip was suitable for the detection of propamocarb in fruits and vegetables.


Asunto(s)
Oro , Nanopartículas del Metal , Anticuerpos Monoclonales , Carbamatos , Inmunoensayo , Límite de Detección
6.
Analyst ; 146(20): 6228-6238, 2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34528034

RESUMEN

We have developed a sensitive and rapid gold nanoparticle-based immunochromatographic strip (GNP-ICS) for the detection of phenacetin (PNCT) and paracetamol (PAP) using an anti-PNCT monoclonal antibody (mAb). The sensitive anti-PNCT mAb (2D6) had a half maximal inhibitory concentration (IC50) and limit of detection (LOD) of 3.51 and 0.21 ng mL-1, respectively. Additionally, its cross-reactivity with PAP was approximately 10.1%. The developed GNP-ICS assay based on GNP-labeled mAb was sensitive for the detection of PNCT with vLOD and cut-off values of 2.5 and 50 ng mL-1 respectively and a vLOD value of 25 ng mL-1 for PAP. Furthermore, the developed icELISA and GNP-ICS assays were applied to determine PNCT-spiked beverage samples without pretreatment, in addition to a kind of PAP-containing drug. The recoveries were validated using high performance liquid chromatography (HPLC). The results revealed that the developed GNP-ICS assay was reliable for the detection of PNCT in practical samples.


Asunto(s)
Oro , Nanopartículas del Metal , Acetaminofén , Cromatografía de Afinidad , Ensayo de Inmunoadsorción Enzimática , Límite de Detección , Fenacetina
7.
Analyst ; 146(12): 3871-3879, 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34028472

RESUMEN

This report describes the development of a sensitive and broadly specific indirect competitive enzyme-linked immunosorbent assay (icELISA) and a gold nanoparticle-based immunochromatographic strip (GNP-ICS) assay for the detection of benzo[a]pyrene (B[a]P), using an anti-B[a]P monoclonal antibody (mAb). A broad-specific anti-B[a]P mAb (4E8) was raised from two types of haptens, with half maximal inhibitory concentrations and limits of detection (LOD) values of 2.51 and 0.54 ng mL-1, respectively. In addition, the cross-reactivity was up to 390% with structurally related compounds. The GNP-ICS assay based on a GNP-labeled mAb showed broad specificity in the detection of B[a]P and its analogues, with cut-off and visual LOD values of 100 and 10 ng mL-1, respectively. Furthermore, the recoveries from the developed icELISA and GNP-ICS assay in edible oil samples spiked with B[a]P were validated by high-performance liquid chromatography-fluorescence detection. The results revealed that the icELISA could reliably detect B[a]P in edible oils.


Asunto(s)
Oro , Nanopartículas del Metal , Anticuerpos Monoclonales , Benzo(a)pireno , Ensayo de Inmunoadsorción Enzimática , Aceites de Plantas
8.
ScientificWorldJournal ; 2014: 267403, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24883370

RESUMEN

On the basis of Evalvid tool integrated in NS2 (Network Simulator version 2), the paper gets new set of tools, myEvalvid, to establish the simulation and evaluation platform for multimedia transmission. Then the paper investigates the effects of various influence factors when multimedia information is transmitted in the network and the relationships among these factors. Based on the analysis, the paper gets different evaluation models, respectively. In this paper, we study the impact on performance of several basic source and network parameters of video streams, namely, GOP (Group of Pictures) pattern, compression quantitative parameters, packet length, and packet error rate. Simulation results show that different parameters lead to different distortion levels which are calculated according to the reconstruction images at the receiver and the original images. The experimental results show that the video transmission and quality evaluation model we designed can evaluate multimedia transmission performance over complex environment very well.


Asunto(s)
Redes de Comunicación de Computadores/organización & administración , Simulación por Computador , Multimedia/normas , Redes de Comunicación de Computadores/normas , Estudios de Evaluación como Asunto , Modelos Teóricos , Procesamiento de Señales Asistido por Computador
9.
Int J Infect Dis ; 15(7): e459-63, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21546303

RESUMEN

OBJECTIVES: We aimed to determine the seroprevalence of Crimean-Congo hemorrhagic fever virus (CCHFV) infection in Yunnan Province, China. MATERIALS AND METHODS: One thousand six hundred and fifty-seven human serum samples and 1280 ticks (Hyalomma asiaticum) were collected from five counties (Menglian, Menghai, Lancang, Mengla, and Ximeng). Serum samples were analyzed independently by indirect immunofluorescence assay and Western blotting to detected CCHFV antibody. The ticks were examined by reverse transcriptase-polymerase chain reaction (RT-PCR) to detect virus RNA. RESULTS: The CCHFV IgG positivity was 3.4% (57/1657). A multivariate analysis was performed, and variables that increased the chance of infection were found to include history of tick bite or contact (odds ratio (OR) 16.6, 95% confidence interval (CI) 7.5-37.0) and age>30 years (OR 6.8, 95% CI 1.6-28.2). The RT-PCR positive rate for ticks was 14.3% (6/42). CONCLUSIONS: The five counties (Menglian, Menghai, Lancang, Mengla, and Ximeng) in Yunnan are areas with the potential for CCHF outbreaks. Residents should protect themselves against tick bites and the surveillance of CCHFV in this region should be improved.


Asunto(s)
Anticuerpos Antivirales/sangre , Virus de la Fiebre Hemorrágica de Crimea-Congo/inmunología , Virus de la Fiebre Hemorrágica de Crimea-Congo/aislamiento & purificación , Fiebre Hemorrágica de Crimea/epidemiología , Ixodidae/virología , Adulto , Animales , China/epidemiología , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Virus de la Fiebre Hemorrágica de Crimea-Congo/clasificación , Virus de la Fiebre Hemorrágica de Crimea-Congo/genética , Fiebre Hemorrágica de Crimea/diagnóstico , Fiebre Hemorrágica de Crimea/virología , Humanos , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , ARN Viral/análisis , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Riesgo , Estudios Seroepidemiológicos , Adulto Joven
10.
Zhonghua Liu Xing Bing Xue Za Zhi ; 32(1): 17-9, 2011 Jan.
Artículo en Chino | MEDLINE | ID: mdl-21518534

RESUMEN

OBJECTIVE: To study the relevant factors on an measles outbreak caused by imported new virus (d11 genotype) from Myanmar and to develop effective strategies and measures. METHODS: On-site investigation on the outbreak was carried out. RESULTS: There were four townships (66%) in Menglian county reported 15 cases of measles, with 7 cases aged 6 months to 5 years old, 2 cases with the history of measles vaccination (MV). Another 8 cases were 21 to 49 year-olds but their histories on immunization were unclear. 14 of the measles cases with Myanmar citizenship came to China for treatment. They were aged 10 months to 13 years old, with only one case had ever received MV vaccination. For all the 29 cases, except for one case who did not adopt the sample case of Myanmar, the remaining 28 patients were positive for measles IgM antibodies. 6 cases of measles virus RNA were detected in the amplified sequence which showed genotype d11, and was considered Myanmar imported wild virus. 184 people received the MV inoculation, with a rate of 61.96% and the serum samples showed a measles IgG antibody positive rate of 87.50%. Manner MV emergency vaccination was carried out timely in that county so the measles outbreak was effectively controlled. CONCLUSION: Imported measles cases from foreign countries might lead to epidemic, indicating the difficulty and challenge in the elimination of measles in our province. Emergent vaccination of MV could interrupt the transmission of the disease. Our experience showed that MV was effective in the prevention of d11 genotypes measles infection in the area.


Asunto(s)
Brotes de Enfermedades , Virus del Sarampión/genética , Sarampión/epidemiología , Sarampión/virología , Adolescente , Adulto , Anticuerpos Antivirales/sangre , Niño , Preescolar , China/epidemiología , Genotipo , Humanos , Lactante , Masculino , Vacuna Antisarampión/administración & dosificación , Persona de Mediana Edad , Mianmar/epidemiología , ARN Viral/aislamiento & purificación , Adulto Joven
11.
Magn Reson Imaging ; 26(3): 401-12, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18082991

RESUMEN

The method Hankel Total Least Squares (HTLS)-PK, which successfully incorporates prior knowledge of known signal poles into the method HTLS, has been proven to greatly improve the performance for parameter estimation of overlapping peaks of magnetic resonance spectroscopy (MRS) signal. In addition, decimation is also proposed as a way to increase the performance of subspace-based parameter estimation methods in the case of oversampling. Taking advantage of decimation in combination with prior knowledge to estimate the MRS signal parameters, two novel subspace-based parameter estimation methods, HTLSDSumPK and HTLSDStackPK, are presented in this paper. The experimental results and relevant analysis show that the methods HTLSDSumPK, HTLSDStackPK and HTLS-PK are slightly better than the method HTLS at low noise levels; however, the three prior-knowledge-incorporating methods, especially the method HTLSDSumPK, have much better performance than the method HTLS at high noise levels in the terms of robustness, estimated accuracy and computational complexity. Even if some inaccuracy of prior knowledge is considered, the method HTLSDSumPK also shows some advantages.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Animales , Química Encefálica , Simulación por Computador , Humanos , Análisis de los Mínimos Cuadrados , Hígado/irrigación sanguínea , Ratas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador
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