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1.
Nano Lett ; 23(12): 5859-5867, 2023 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-36971675

RESUMEN

The so-called "hard-to-transfect cells" are well-known to present great challenges to intracellular delivery, but detailed understandings of the delivery behaviors are lacking. Recently, we discovered that vesicle trapping is a likely bottleneck of delivery into a type of hard-to-transfect cells, namely, bone-marrow-derived mesenchymal stem cells (BMSCs). Driven by this insight, herein, we screened various vesicle trapping-reducing methods on BMSCs. Most of these methods failed in BMSCs, although they worked well in HeLa cells. In stark contrast, coating nanoparticles with a specific form of poly(disulfide) (called PDS1) nearly completely circumvented vesicle trapping in BMSCs, by direct cell membrane penetration mediated by thiol-disulfide exchange. Further, in BMSCs, PDS1-coated nanoparticles dramatically enhanced the transfection efficiency of plasmids of fluorescent proteins and substantially improved osteoblastic differentiation. In addition, mechanistic studies suggested that higher cholesterol content in plasma membranes of BMSCs might be a molecular-level reason for the greater difficulty of vesicle escape in BMSCs.


Asunto(s)
Células de la Médula Ósea , Desarrollo Industrial , Humanos , Células HeLa , Transfección , Diferenciación Celular , Células Cultivadas
2.
Org Biomol Chem ; 19(8): 1738-1743, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33543173

RESUMEN

An efficient nano-Cu2O-catalyzed cascade multicomponent reaction of 2-halobenzoic acids and trimethylsilyl cyanide with diverse amines was developed using water as a solvent, affording versatile N-substituted phthalimide derivatives in moderate to excellent yields. This novel strategy features carbon monoxide gas-free, environmentally benign, one-pot multistep transformation, commercially available reagents, a cheap catalyst without any additives, wide functional group tolerance, and operational convenience.

3.
J Org Chem ; 85(8): 5691-5701, 2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-32237749

RESUMEN

Cu-catalyzed domino decyanation and cyanation reaction of acyl cyanides with amines or alcohols have been developed. The cyano sources were generated in situ via C-CN cleavage yielding the corresponding cyano substituted amides or esters in moderate to excellent yields. This approach features a cheap copper catalyst, domino decyanation and cyanation reaction, readily available starting materials, broad substrate scope, operational simplicity, and the potential for further transformation of the cyano group.

4.
Mikrochim Acta ; 187(9): 515, 2020 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-32839875

RESUMEN

To early effectively detect amyloid-beta (Aß) oligomers, a label-free reusable aptasensor was designed. This aptasensor based on a luminescent nanoscale lanthanum-based metal-organic framework (L-MOF)-armored single-stranded DNA antibody (MOF-armored-anti-DNA antibody) as signal tags and aptamer bound to magnetic beads (Apt-MB) as capture probe. The reusable aptasensor combines signal tag and capture probe with antigen-antibody interaction. When the reusable aptasensor is formed, the strong fluorescence intensity of L-MOF will "turn off" by photo-induced electron transfer from excited states to an unfilled d shell of iron cations on the nanoparticle surface. Upon the presence of Aß oligomers in serum samples, they can be especially distinguished with the Aß oligomers aptamer in capture probes and then signal tags are released into the solution for developing the fluorescence aptasensor under excitation/emission 365 nm/430 nm. Meanwhile, the aptamer was recovered from the complex of Aß oligomers/Apt-MB by heat treatment. When the temperature returns to room temperature, the recovered aptamer in the capture probe can once again bound to the MOF-armored-anti-DNA antibody for reuse. The label-free reusable aptasensor system detection has high sensitivity and selectivity toward Aß oligomers (LOD = 0.4 pg/mL) and an excellent linear range (0.001-100 ng/mL). This strategy is a fruitful step for the development of reusable aptasensor and may turn on new avenues for the applications of Aß oligomer detection in clinical diagnosis.Graphical abstract.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/sangre , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Péptidos beta-Amiloides/química , Anticuerpos Inmovilizados/inmunología , Aptámeros de Nucleótidos/inmunología , ADN de Cadena Simple/química , ADN de Cadena Simple/inmunología , Colorantes Fluorescentes/química , Humanos , Separación Inmunomagnética , Lantano/química , Límite de Detección , Nanopartículas de Magnetita/química , Estructuras Metalorgánicas/química , Estructura Cuaternaria de Proteína , Espectrometría de Fluorescencia
5.
J Org Chem ; 84(3): 1630-1639, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30608171

RESUMEN

A catalyst and additive-free annulation of 2-pyridylacetates and ynals under molecular oxygen was the first developed, affording 3-acylated indolizines in good to excellent yields. Molecular oxygen was used as the source of the carbonyl oxygen atom in indolizines. This approach was compatible with a wide range of functional groups, and especially it has been successfully extended to unsaturated double bonds and triple bonds, which were difficult to prepare by previous methods in a single step.

6.
Org Biomol Chem ; 16(8): 1247-1251, 2018 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-29379941

RESUMEN

An efficient synthesis of a variety of pyridyl benzamides from 2-aminopyridines and nitroolefins is described. This rare-earth-metal-catalyzed reaction provides the corresponding products with broad substrate scope in moderate to excellent yields, in the absence of additives and external oxidants. Water is used as the source of the carbonyl oxygen atom in pyridyl benzamides. Furthermore, 2-substituted oxazolo[4,5-b]pyridines are formed in good yields under the standard conditions when 2-aminopyridin-3-ols are used as the substrates.

7.
Org Biomol Chem ; 16(44): 8481-8485, 2018 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-30378615

RESUMEN

A new tandem decyanation/cyanation reaction of α-iminonitriles has been developed. A variety of cyano-substituted aryl amides and heteroaryl amides are synthesized in good yields. Both electron-rich and electron-deficient groups are compatible with the standard conditions. This reaction features a nonmetallic cyano source, tandem decyanation and cyanation reaction, waste utilization of the HCN from the hydrolysis of α-iminonitriles, formation of two important functional groups in one-step operation, etc.

8.
Med Sci Monit ; 24: 3357-3365, 2018 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-29783268

RESUMEN

BACKGROUND Increasing the success rate of in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) is a duty of clinicians that has made many seek a variety of protocols. This study was undertaken to use a liquid chromatography-mass spectrometry (LC-MS) to define the alterations of follicular fluid (FF) lipid metabolites in patients undergoing progestin-primed ovarian stimulation (PPOS) compared with short-term protocol, revealing potential correlations between the differentially expressed lipids and ameliorative clinical outcomes. MATERIAL AND METHODS Ninety-three infertile women undergoing IVF/ICSI treatment with PPOS (n=62) or a short-term protocol (n=31) were prospectively enrolled in a randomized controlled trial. FF samples were obtained from dominant follicles at the time of oocyte retrieval. Lipid metabolism profiles were analyzed using LC-MS. RESULTS Twelve lipids were found to be higher in patients treated with the PPOS protocol than in those receiving the short-term protocol, including triacylglycerols (TAG-34: 1+NH4, TAG-58: 0+NH4, TAG-64: 3+NH4, and TAG-64: 8+NH4), diacylglycerol DAG-38: 6+NH4, phosphatidylglycerols (PG-26: 0, PG-30: 2, and PG-40: 5), phosphatidylethanolamine PE-32: 2, lysophosphatidylethanolamine LPE-14: 1, lysophosphatidylinositol LPI-12: 0, and lysophosphatidylcholine LPC-16: 0. CONCLUSIONS Our data demonstrate that the PPOS protocol increases the levels of 12 lipids in FF, which reveals a strong association between the differentially elevated lipids and better IVF/ICSI outcomes.


Asunto(s)
Líquido Folicular/metabolismo , Lípidos/análisis , Metaboloma/efectos de los fármacos , Inducción de la Ovulación , Progestinas/farmacología , Adulto , Análisis Discriminante , Femenino , Líquido Folicular/efectos de los fármacos , Humanos , Análisis de los Mínimos Cuadrados , Reconocimiento de Normas Patrones Automatizadas , Progestinas/sangre , Factores de Tiempo , Resultado del Tratamiento
9.
Zhonghua Gan Zang Bing Za Zhi ; 23(3): 166-70, 2015 Mar.
Artículo en Zh | MEDLINE | ID: mdl-25938826

RESUMEN

OBJECTIVE: To investigate the role of R-Spondinl in the activation of hepatic stellate cells (HSCs). METHODS: Twenty-four healthy male Kunming mice were randomly divided into the following two groups:fibrosis model group (n=16) and control group (n=8). Hepatic fibrosis was induced by subcutaneous injections of CC14 (20% in olive oil) at a dose of 5 ml/kg twice per week. After 10 weeks, the animals were sacrificed by CO(2) over-exposure and liver tissues were harvested.The protein and mRNA levels of R-Spondin1, alphat-SMA,and collagen I were examined by Western blot assay and real-time PCR respectively. Additionally,HSCs were isolated from the mice liver tissues to examine the time-series expression changes of R-Spondinl, alpha-SMA, and nuclear beta-catenin.TCF activity was analyzed by luciferase reporter assay.Moreover,HSCs were cocultured with recombinant R-Spondin1 and DKK1 to evaluate dose-response. RESULTS: R-Spondinl expression was significantly higher in the fibrosis model group than in the control group (protein level:3.16 ± 0.18 vs. 0.99 ± 0.16, t =13.31, P < 0.01; mRNA level:4.36 ± 0.26 vs. 0.98 ± 0.12, t =21.46, P < 0.01).The culture-activated mouse HSCs showed up-regulated TCF activity (5.33 ± 0.34 vs. non-activated: 1.03 ± 0.09, t =20.93, P < 0.01), nuclear beta-catenin expression (4.47 ± 0.21 vs. 0.97 ± 0.14, t =25.25, P < 0.01), and R-Spondin1 expression (protein level: 4.54 ± 0.18 vs. 1.04 ± 0.12, t =31.17, P < 0.01; mRNA level:5.13 ± 0.15 vs. 1.01 ± 0.16, t=38.06, P < 0.01). Exogenous stimulation of freshly isolated mouse HSCs with recombinant R-Spondin1 induced a dose-dependent increase in both TCF activity and the expression of nuclear beta-catenin and alphat-SMA. DKK1 down-regulated activities of factors in the WNT signaling pathway and repressed activation of HSCs. Conclusion R-Spondin1 may promote HSC activation by enhancing the canonical WNT signaling pathway.


Asunto(s)
Células Estrelladas Hepáticas , Animales , Regulación hacia Abajo , Proteínas de la Matriz Extracelular , Cirrosis Hepática , Masculino , Ratones , ARN Mensajero , Vía de Señalización Wnt , beta Catenina
10.
Zhonghua Yi Xue Za Zhi ; 94(12): 899-902, 2014 Apr 01.
Artículo en Zh | MEDLINE | ID: mdl-24854908

RESUMEN

OBJECTIVE: To explore the association of Jab1 (c-Jun activation domain binding protein 1) expression during carcinogenesis and clinicopathological characteristics of colorectal carcinoma (CRC) . METHODS: Tissue specimens were obtained from 80 cases of CRC from January 2007 to December 2008. And the expression of Jab1 protein for each specimen was detected by immunohistochemistry (EnVision). Six representative paired samples of cancerous and paired adjacent normal tissues were collected for Western blot. The relationships between the expression level of Jab1 protein and the clinicopathological characteristics of primary CRC were retrospectively analyzed. RESULTS: A high-level expression of Jab1 was present in cancerous tissues but not in paired adjacent normal tissues. The positive expression rate of Jab1 protein was as high as 96.3% (77/80) . And its high expression rate was 82.5% (66/80) , low expression rate 17.5% (14/80) and 8.8% (7/80) in cancerous and paired adjacent normal tissues respectively (P < 0.05) . Its expression was correlated with differentiation, invasion depth, TNM stage and lymph node metastasis (all P < 0.05) . Jab1 was significantly correlated with Ki-67 (r = 0.548, P < 0.01) and inversely with p27(kip1) (r = -0.461, P < 0.01). CONCLUSIONS: An over-expression of Jab1 protein might play an important role in the pathogenesis of CRC. Thus it may become a novel diagnostic marker and a therapeutic target in patients with CRC.


Asunto(s)
Carcinoma/metabolismo , Neoplasias Colorrectales/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptido Hidrolasas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Complejo del Señalosoma COP9 , Carcinoma/patología , Neoplasias Colorrectales/patología , Femenino , Humanos , Inmunohistoquímica , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos
11.
Wei Sheng Wu Xue Bao ; 54(8): 913-8, 2014 Aug 04.
Artículo en Zh | MEDLINE | ID: mdl-25345023

RESUMEN

OBJECTIVE: To study the transformation of 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoates (HOPDAs) by laccase from Trametes sp. SQO1 so to further understand the new catalytic properties of laccase and solve the problem of accumulations of HOPDAs in polychlorinated biphenyls (PCBs) degradation. METHODS: With UV-vis spectrophotometer, we studied the transformations of 8 substituted HOPDAs by laccase, and measured the steady-state kinetics parameters of laccase against parts of HOPDAs. RESULTS: Laccase catalyzed HOPDAs to colorless substances without any mediators; among them, especially 3,8,11-3Cl HOPDA that was barely transformed by 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate hydrolase (BphD) and Rhodococcus sp. R04, also could be transformed by this laccase. The analysis of the steady-state kinetics indicated that 10-Cl HOPDA was the optimal substrate of laccase among 5 HOPDAs, and the Km was lower than that of HOPDA and 8-Cl HOPDA. Although 3, 10-2F HOPDA was not the optimal substrate (Km = 17.02 micromol/L), its transformation efficiency (k(cat)/Km) was the highest. CONCLUSION: Laccase from Trametes sp. SQOl could transform various HOPDAs effectively, and has its potential in eliminating PCB pollution.


Asunto(s)
Ácidos Grasos Insaturados/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Lacasa/química , Lacasa/metabolismo , Trametes/enzimología , Biodegradación Ambiental , Biotransformación , Proteínas Fúngicas/genética , Cinética , Lacasa/genética , Trametes/química , Trametes/genética
12.
Poult Sci ; 103(1): 103230, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37980761

RESUMEN

In China, fresh food has always been a top priority and live poultry has been a staple in the diet for thousands of years. As a result, the live poultry market (LPM) remains a popular and important source for purchasing live poultry among the public. However, LPMs also play a crucial role in spreading and retaining highly pathogenic avian influenza (HPAI) due to the high poultry movement and trade volume. Therefore, the preventive behavior of LPM vendors is essential in blocking the transmission of HPAI and reducing occupational exposure. Based on the health belief model, this study utilized structural equation modeling to examine the effect of risk perceptions on preventive behavior among vendors in the live poultry wholesale market (wLPM) and the live poultry retail market (rLPM) in Guangdong Province. The results indicated that perceived severity and perceived benefits positively influenced the wLPM vendors' ability to adopt preventive behavior (i.e., self-efficacy) while perceived barriers negatively affected self-efficacy in both wLPM and rLPM. Moreover, cues to action positively mediated the relationship between perceived severity, perceived benefits, and self-efficacy of wLPM and rLPM vendors. Cues to action also positively mediated the effect of perceived susceptibility among wLPM vendors. To promote preventive behavior among vendors, the market management companies and the government must provide timely and effective HPAI information through various channels and develop differentiated health campaigns according to the market types to raise vendors' awareness about HPAI.


Asunto(s)
Gripe Aviar , Animales , Gripe Aviar/prevención & control , Aves de Corral , Pollos , Comercio , China
13.
Int J Pharm ; 658: 124231, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38759741

RESUMEN

Two frequent problems hindering clinical translation of nanomedicine are low drug loading and low colloidal stability. Previous efforts to achieve ultrahigh drug loading (>30 %) introduce new hurdles, including lower colloidal stability and others, for clinical translation. Herein, we report a new class of drug nano-carriers based on our recent finding in protein-nanoparticle co-assembly supraparticle (PNCAS), with both ultrahigh drug loading (58 % for doxorubicin, i.e., DOX) and ultrahigh colloidal stability (no significant change in hydrodynamic size after one year). We further show that our PNCAS-based drug nano-carrier possesses a built-in environment-responsive drug release feature: once in lysosomes, the loaded drug molecules are released instantly (<1 min) and completely (∼100 %). Our PNCAS-based drug delivery system is spontaneously formed by simple mixing of hydrophobic nanoparticles, albumin and drugs. Several issues related to industrial production are studied. The ultrahigh drug loading and stability of DOX-loaded PNCAS enabled the delivery of an exceptionally high dose of DOX into a mouse model of breast cancer, yielding high efficacy and no observed toxicity. With further developments, our PNCAS-based delivery systems could serve as a platform technology to meet the multiple requirements of clinical translation of nanomedicines.


Asunto(s)
Doxorrubicina , Liberación de Fármacos , Lisosomas , Nanopartículas , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Doxorrubicina/farmacocinética , Animales , Nanopartículas/química , Femenino , Portadores de Fármacos/química , Ratones , Coloides/química , Humanos , Sistemas de Liberación de Medicamentos , Ratones Endogámicos BALB C , Estabilidad de Medicamentos , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Línea Celular Tumoral , Neoplasias de la Mama/tratamiento farmacológico
14.
Foods ; 12(3)2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36766045

RESUMEN

As a representative of Chinese alcoholic drinks, baijiu has developed into a mass-consumption commodity. Its simple industrial chain makes it a suitable target for fraudsters. In order to understand the differences and potential factors of fraud vulnerability among groups at various levels, this study constructed a food fraud vulnerability assessment system for the Chinese baijiu supply chain based on routine activities theory. We examined the fraud vulnerability in the baijiu supply chain with data from 243 producers and 45 retailers by using the safe supply of affordable food everywhere (SSAFE) food fraud vulnerability assessment (FFVA) tool. The results indicate that fraud factors related to opportunities have an overall medium vulnerability, while those related to motivations and control measures have an overall medium-low vulnerability. In addition, there are significant differences in the perceived vulnerability of fraud factors across the supply chain. Moreover, retailers have overall higher fraud vulnerability in terms of opportunities and control measures than producers. The main reasons for the frequent occurrence of fraud in the baijiu industry are numerous technical opportunities, strong economic drivers, and insufficient control measures.

15.
Foods ; 12(20)2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37893691

RESUMEN

The demand for pre-made dishes has increased in China. However, a detailed understanding of residents' intention to consume pre-made dishes is lacking in the existing studies. This research aims to investigate the consumer motives and intention to consume pre-made dishes. Through in-depth interviews and analysis, this research explores the factors influencing the residents' intention along the research steps of grounded theory. Fifty-one residents participated in semi-structured interviews via face-to-face or online interviews. Three motives for purchasing pre-made dishes were attitude, subjective norm, and perceived control. These were influenced by external factors, including environmental features and product features. Subjective characteristics are pre-existing characteristics of individuals themselves, including cooking skills, food skills, housework allocation, and eating attitudes, which play a moderating role in the relationship between external factors and consumer motives. Based on the six major categories, this study built a model of the formation mechanism of the consumer intention to consume pre-made dishes. It revealed the psychological attribution of residents' consumption of pre-made dishes. The finding of this study contributes to the understanding of the internal logic of PMDs' consumer intention formation. It would be a guide for researchers to map out appropriate business development strategies, and provide evidence for the government in formulating management policies.

16.
Environ Pollut ; 335: 122265, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37517641

RESUMEN

The simultaneous determination of carbaryl and its metabolite 1-naphthol is essential for risk assessment of pesticide exposure in agricultural and environmental samples. Herein, several bispecific nanobodies (BsNbs) with different lengths of hydrophilic linkers and junction sites were prepared and characterized for the simultaneous recognition of carbaryl and its metabolite 1-naphthol. It was found that the affinity of BsNbs to the analytes could be regulated by controlling linker length and linking terminal. Additionally, molecular simulation revealed that linker lengths affected the conformation of BsNbs, leading to alteration in sensitivity. The BsNb with G4S linker, named G4S-C-N-VHH, showing good thermal stability and sensitivity was used to develop a bispecific indirect competitive enzyme-linked immunosorbent assay (Bic-ELISA). The assay demonstrated a limit of detection of 0.8 ng/mL for carbaryl and 0.4 ng/mL for 1-naphthol in buffer system. Good recoveries from soil and rice samples were obtained, ranging from 80.0% to 112.7% (carbaryl) and 76.5%-110.8% (1-naphthol), respectively. Taken together, this study firstly provided a BsNb with high sensitivity and efficiency against environmental pesticide and its metabolite, and firstly used molecular dynamics simulation to explore the influence of linker on recognition. The results are valuable for the application of immunoassay with high efficiency in the fields of environment and agriculture.


Asunto(s)
Insecticidas , Oryza , Carbaril/análisis , Insecticidas/análisis , Suelo , Ensayo de Inmunoadsorción Enzimática/métodos
17.
Artículo en Inglés | MEDLINE | ID: mdl-35897407

RESUMEN

Unhealthy eating is one cause of obesity and some chronic non-communicable diseases. This study introduces self-efficacy and health consciousness to construct an extended health belief model (HBM) to examine the factors influencing healthy eating intentions and behaviors of Chinese residents and explore the moderating effect of perceived barriers and the mediating effect of healthy eating intentions. Through the survey platform "Questionnaire Star", this study collected quantitative data from 1281 adults, and partial least squares structural equation modeling was used for confirmatory factor analysis, path analysis, importance-performance map analysis, and multi-group analysis. Results showed that perceived susceptibility, perceived severity, perceived benefits, self-efficacy, and health consciousness had a significant positive effect on residents' healthy eating intentions. Perceived barriers had a significant negative effect on residents' healthy eating intentions. Healthy eating intentions had a significant positive effect on healthy eating behaviors. Perceived barriers played a significant negative moderating effect between healthy eating intentions and behaviors. Healthy eating intentions had a positive and significant mediating effect. The multi-group analysis showed that extended HBM has relative generalization ability. The extended HBM has good explanatory and predictive power for healthy diet and provides a new framework for understanding the influencing factors of individuals' healthy eating intentions and behaviors.


Asunto(s)
Dieta Saludable , Intención , Adulto , China , Modelo de Creencias sobre la Salud , Humanos , Autoeficacia
18.
Comput Intell Neurosci ; 2022: 2661231, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36268144

RESUMEN

Remote-sensing image scene data contain a large number of scene images with different scales. Traditional scene classification algorithms based on convolutional neural networks are difficult to extract complex spatial distribution and texture information in images, resulting in poor classification results. In response to the above problems, we introduce the vision transformer network structure with strong global modeling ability into the remote-sensing image scene classification task. In this paper, the parallel network structure of the local-window self-attention mechanism and the equivalent large convolution kernel is used to realize the spatial-channel modeling of the network so that the network has better local and global feature extraction performance. Experiments on the RSSCN7 dataset and the WHU-RS19 dataset show that the proposed network can improve the accuracy of scene classification. At the same time, the effectiveness of the network structure in remote-sensing image classification tasks is verified through ablation experiments, confusion matrix, and heat map results comparison.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Tecnología de Sensores Remotos/métodos
19.
Front Psychol ; 13: 901169, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36337483

RESUMEN

China's fishery industry has national and international relevance whose aquaculture production accounts for more than 60 percent of the world's total aquaculture production. But the average amount of pesticides used per hectare in China is roughly five times of the world average. The abuse of chemical fertilizers and drugs has brought chronic, long-term, and cumulative harm to both human beings and environment. The digital agricultural management system should be adopted to reduce non-negligible environment pollution and the quality and safety risks of aquatic products. So, it is essential to understand the factors that may influence the adopting intention of this digital management approaches. The present study aimed to examine the adopting intention of farmers toward the digital agricultural management system using two theories-the theory of planned behavior (TPB) and the behavioral economics-as the research framework. The population was composed of farmers in the provinces of Guangdong province in south China of whom 219 farmers were sampled with stratified random sampling technique. Structural equation modeling was used to analyze the data, and it was revealed that this research framework could potentially predict intention. And we observed that the two biased belief of availability bias and loss aversion bias can be the main predictive influence factors of responsible behaviors in adopting the digital agriculture management system, which highlights the importance of framing recommendations in terms of losses rather than gain may be more effective to increase farmers' intention to adopt the digital system on their farms.

20.
World J Clin Cases ; 10(24): 8587-8598, 2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36157818

RESUMEN

BACKGROUND: The value of conventional magnetic resonance imaging in the differential diagnosis of thyroid nodules is limited; however, the value of multi-parameter diffusion-weighted imaging (DWI) in the quantitative evaluation of thyroid nodules has not been well determined. AIM: To determine the utility of multi-parametric DWI including mono-exponential, bi-exponential, stretched exponential, and kurtosis models for the differentiation of thyroid lesions. METHODS: Seventy-nine patients (62 with benign and 17 with malignant nodules) underwent multi-b value diffusion-weighted imaging of the thyroid. Multiple DWI parameters were obtained for statistical analysis. RESULTS: Good agreement was found for diffusion parameters of thyroid nodules. Malignant lesions displayed lower diffusion parameters including apparent diffusion coefficient (ADC), the true diffusion coefficient (D), the perfusion fraction (f), the distributed diffusion coefficient (DDC), the intravoxel water diffusion heterogeneity (α) and kurtosis model-derived ADC (Dapp), and higher apparent diffusional kurtosis (Kapp) than benign entities (all P < 0.01), except for the pseudodiffusion coefficient (D*) (P > 0.05). The area under the ROC curve (AUC) of the ADC(0 and 1000) was not significantly different from that of the ADC(0 and 2000), ADC(0 to 2000), ADC(0 to 1000), D, DDC, Dapp and Kapp (all P > 0.05), but was significantly higher than the AUC of D*, f and α (all P < 0.05) for differentiating benign from malignant lesions. CONCLUSION: Multiple DWI parameters including ADC, D, f, DDC, α, Dapp and Kapp could discriminate benign and malignant thyroid nodules. The metrics including D, DDC, Dapp and Kapp provide additional information with similar diagnostic performance of ADC, combination of these metrics may contribute to differentiate benign and malignant thyroid nodules. The ADC calculated with higher b values may not lead to improved diagnostic performance.

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