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1.
Food Res Int ; 162(Pt A): 112008, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36461234

RESUMEN

This study examined the chemical compounds and bioactivity of the aqueous extract of Clitoria ternatea blue petals and investigated its beneficial effects in vivo on a mouse model of obesity and metabolic syndrome. The extract mainly contained flavonoids, and nine compounds were tentatively identified. Male C57BL/6J mice were either fed a standard diet (SD) or a high-fat, high-fructose diet (HFFD) for 16 weeks, and HFFD-fed animals were treated with 0.25%, 0.5%, and 2% (w/w) of the aqueous extract in drinking water. The aqueous extract ameliorated oxidative stress and inflammation mediators. Furthermore, the aqueous extract reduced plasma leptin, free fatty acid, low-density lipoprotein cholesterol levels and hepatic malondialdehyde content. The aqueous extract significantly reduced total cholesterol and ameliorated insulin resistance. The results demonstrated that the aqueous extract of C. ternatea blue petals contains bioactive anthocyanins that exert substantial hypolipidemic and anti-inflammatory effects by promoting reverse cholesterol transport in HFFD-fed mice.


Asunto(s)
Clitoria , Fructosa , Masculino , Ratones , Animales , Fructosa/efectos adversos , Antocianinas , Ratones Endogámicos C57BL , Obesidad/tratamiento farmacológico , Obesidad/prevención & control , Inflamación/prevención & control , Estrés Oxidativo , Colesterol
2.
Artículo en Inglés | MEDLINE | ID: mdl-35627404

RESUMEN

Real-time regional risk prediction can play a crucial role in preventing traffic accidents. Thus, this study established a lane-level real-time regional risk prediction model. Based on observed data, the least squares-support vector machines (LS-SVM) algorithm was used to identify each lane region of the mainline, and the initial traffic parameters and surrogate safety measures (SSMs) were extracted and aggregated. The negative samples that characterized normal traffic and the positive samples that characterized regional risk were identified. Mutual information (MI) was used to determine the information gain of various feature variables in the samples, and the key feature variables affecting the regional conditions were tested and screened by means of binary logit regression analysis. Upon screening the variables and corresponding labels, the construction and verification of a lane-level regional risk prediction model was completed using the catastrophe theory. The results showed that lane difference is an important parameter to reduce the uncertainty of regional risk, and its odds ratio (OR) was 16.30 at the 95% confidence level. The 10%-quantile modified time to collision (MTTC) inverse, the speed difference between lanes, and 10%-quantile headway (DHW) had an obvious influence on regional status. The model achieved an overall accuracy of 86.50%, predicting 84.78% of regional risks with a false positive rate of 13.37% and 86.63% of normal traffic with a false positive rate of 15.22%. The proposed model can provide a basis for formulating individualized active traffic control strategies for different lanes.


Asunto(s)
Accidentes de Tránsito , Algoritmos , Accidentes de Tránsito/prevención & control , Recolección de Datos , Máquina de Vectores de Soporte
3.
Artículo en Inglés | MEDLINE | ID: mdl-33562665

RESUMEN

In complex traffic environments, collision warning systems that rely only on in-vehicle sensors are limited in accuracy and range. Vehicle-to-infrastructure (V2I) communication systems, however, offer more robust information exchange, and thus, warnings. In this study, V2I was used to analyze side-collision warning models at non-signalized intersections: A novel time-delay side-collision warning model was developed according to the motion compensation principle. This novel time-delay model was compared with and verified against a traditional side-collision warning model. Using a V2I-oriented simulated driving platform, three vehicle-vehicle collision scenarios were designed at non-signalized intersections. Twenty participants were recruited to conduct simulated driving experiments to test and verify the performance of each collision warning model. The results showed that compared with no warning system, both side-collision warning models reduced the proportion of vehicle collisions. In terms of efficacy, the traditional model generated an effective warning in 84.2% of cases, while the novel time-delay model generated an effective warning in 90.2%. In terms of response time and conflict time difference, the traditional model gave a longer response time of 0.91 s (that of the time-delay model is 0.78 s), but the time-delay model reduced the driving risk with a larger conflict time difference. Based on an analysis of driver gaze change post-warning, the statistical results showed that the proportion of effective gaze changes reached 84.3%. Based on subjective evaluations, drivers reported a higher degree of acceptance of the time-delay model. Therefore, the time-delay side-collision warning model for non-signalized intersections proposed herein can improve the applicability and efficacy of warning systems in such complex traffic environments and provide reference for safety applications in V2I systems.


Asunto(s)
Accidentes de Tránsito , Conducción de Automóvil , Comunicación , Humanos , Tiempo de Reacción , Seguridad
4.
J Inequal Appl ; 2017(1): 103, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28539753

RESUMEN

We investigate a stochastic optimal control problem where the controlled system is depicted as a stochastic differential delayed equation; however, at the terminal time, the state is constrained in a convex set. We firstly introduce an equivalent backward delayed system depicted as a time-delayed backward stochastic differential equation. Then a stochastic maximum principle is obtained by virtue of Ekeland's variational principle. Finally, applications to a state constrained stochastic delayed linear-quadratic control model and a production-consumption choice problem are studied to illustrate the main obtained result.

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