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1.
Sensors (Basel) ; 24(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38474944

RESUMO

In this paper, we introduce a novel panoptic segmentation method called the Mask-Pyramid Network. Existing Mask RCNN-based methods first generate a large number of box proposals and then filter them at each feature level, which requires a lot of computational resources, while most of the box proposals are suppressed and discarded in the Non-Maximum Suppression process. Additionally, for panoptic segmentation, it is a problem to properly fuse the semantic segmentation results with the Mask RCNN-produced instance segmentation results. To address these issues, we propose a new mask pyramid mechanism to distinguish objects and generate much fewer proposals by referring to existing segmented masks, so as to reduce computing resource consumption. The Mask-Pyramid Network generates object proposals and predicts masks from larger to smaller sizes. It records the pixel area occupied by the larger object masks, and then only generates proposals on the unoccupied areas. Each object mask is represented as a H × W × 1 logit, which fits well in format with the semantic segmentation logits. By applying SoftMax to the concatenated semantic and instance segmentation logits, it is easy and natural to fuse both segmentation results. We empirically demonstrate that the proposed Mask-Pyramid Network achieves comparable accuracy performance on the Cityscapes and COCO datasets. Furthermore, we demonstrate the computational efficiency of the proposed method and obtain competitive results.

2.
Sci Rep ; 12(1): 9791, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35697845

RESUMO

Anger is a key factor affecting drivers' subjective judgment and driving skills. The influence of anger on driving behavior has been widely studied, but there is a lack of comparative research under different lighting conditions. Through a driving simulation experiment, this paper studies the influence of anger on left-turn driving behavior under two light conditions day and night. In the experiment, 32 licensed participants were divided into two groups, one in emotional neutrality and the other in anger. Among them, the emotional state of anger is induced by a traffic-related video. The results showed that compared with daytime participants, participants at night had higher anger intensity, shorter gap acceptance, and post encroachment time (PET) when left-turn driving. In addition, compared with neutral emotion participants, angry participants tended to accept shorter gap acceptance and PET when turning left. This indicates that participants failed to respond correctly to left-turn driving behavior in a state of anger. However, the response of gender differences to situational driving anger was not affected by light conditions. The anger intensity of male participants during the day and night was higher than that of female participants, and the gap between acceptance and PETs during left-turn was shorter than that of female participants. This shows that male participants are more likely to produce high-intensity anger and are more likely to make dangerous driving decisions in a state of anger. This paper puts forward some suggestions on identifying anger and preventing angry driving.


Assuntos
Condução de Veículo , Iluminação , Acidentes de Trânsito/prevenção & controle , Agressão/psicologia , Ira , Comportamento Perigoso , Feminino , Humanos , Masculino
3.
PLoS One ; 17(3): e0265267, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35294493

RESUMO

Drivers' driving decisions at yellow lights are an important cause of accidents at intersections. As proved by existing studies, driving style is an important basis for a driver to decide to pass a yellow light or not. This study, therefore, aims to investigate the effects of different driving styles on driving decisions at yellow lights under different lighting conditions. Specifically, 64 licensed drivers were recruited to comparative study the effects of different driving styles on the decision to pass through yellow lights under both daytime and nighttime lighting conditions using a driving simulator and a VR device. The results showed that maladjusted drivers more likely to pass the yellow light faster than adapted drivers (81.25% vs 43.75%) during both day and night. Male drivers had higher overall driving style scores than female drivers, and male drivers were faster and more likely to pass a yellow light than female drivers (56.25% vs 31.25%). This study also found that inexperienced drivers were faster and more likely to pass a yellow light than experienced drivers (50% vs 37.5%). Overall, maladjusted drivers are more likely to pass yellow lights, which can be improved and society properties by enhancing driving learning for maladjusted drivers.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Simulação por Computador , Feminino , Humanos , Iluminação , Masculino
4.
Med Sci Monit ; 27: e928214, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33767128

RESUMO

BACKGROUND Normal profiles of FBAs in healthy neonates and children in Kunming city and surrounding areas in China have not been previously determined. The objective of this study was to determine a developmental pattern of fecal bile acids (FBAs) in healthy neonates and children. MATERIAL AND METHODS A cross-sectional study was performed on 238 healthy neonates and children recruited in the First Affiliated Hospital of Kunming Medical University, China from October 2015 to September 2016. Secreted primary and secondary FBAs in fresh feces were quantitated by liquid chromatography mass spectrometry (LC-MS). Amounts of FBAs in feces were compared among various age groups. RESULTS Trace amounts of cholic acid and chenodiol acid of primary FBAs were detectable at day 3 after birth, with a significant increase from day 3 to day 7. The primary FBAs gradually decreased from day 25 to the age of 6 years old. In contrast, a significant amount of glycochenodeoxycholic acid was detected on day 3 but decreased to a trace amount by day 7 and onwards. Primary FBAs appeared to maintain a high level, accounting for 98% of total FBAs, with no significant changes from day 7 to day 25 after birth. They gradually decreased from 90% to 10% from age 6 months to 6 years old. While the secondary FBAs were barely detected in neonates, only accounting for 2% of total FBAs, they were gradually elevated to 90% of total FBAs from age 6 months to 6 years old. CONCLUSIONS The liver can effectively synthesize primary bile acids 7 days after birth, and fecal primary bile acids tend to be stable after the neonate stage. Secondary bile acids continuously increase along with the maturation of intestinal flora, which reaches a relatively stable level at around 3 years old.


Assuntos
Ácidos e Sais Biliares/metabolismo , Fezes/química , Fígado/metabolismo , Ácidos e Sais Biliares/análise , Criança , China , Cromatografia Líquida , Estudos Transversais , Feminino , Microbioma Gastrointestinal , Humanos , Recém-Nascido , Masculino , Espectrometria de Massas
5.
IEEE Trans Neural Netw Learn Syst ; 31(6): 2209-2216, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31380769

RESUMO

This brief further explores the problem of finite-time synchronization of delayed recurrent neural networks with the mismatched parameters and neuron activation functions. An improved sliding mode control approach is presented for addressing the finite-time synchronization problem. First, by employing the drive-response concept and the synchronization error of drive-response systems, a novel integral sliding mode surface is constructed such that the synchronization error can converge to zero in finite time along the constructed integral sliding mode surface. Second, a suitable sliding mode controller is designed by relying on Lyapunov stability theory such that all system state trajectories can be driven onto the predefined sliding mode surface in finite time. Moreover, it is found that the presented control approach can be conveniently verified and does not need to solve any linear matrix inequality (LMI) to guarantee the finite-time synchronization of delayed recurrent neural networks. Finally, three numerical examples are exploited to demonstrate the effectiveness of the presented control approach.

6.
Zhongguo Zhong Yao Za Zhi ; 44(11): 2266-2273, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359652

RESUMO

A high-content GABA was found in Sojae Semen Praeparatum(SSP), which is a famous traditional Chinese medicine and officially listed in Chinese Pharmacopoeia. To screen out and identify GABA-producing microbes from samples at different time points during the fermenting process of SSP, traditional microbiological methods combined with molecular biological methods were used to study the predominant GABA-producing microorganisms existing in the fermenting process of SSP. This study would lay a foundation for further studying the processing mechanism of SSP. The fermenting process of SSP was based on Chinese Pharmacopoeia(2010 edition), and samples were taken at different time points during the fermenting process of SSP. The bacteria and fungi from samples at different time points in the fermenting process of SSP were cultured, isolated and purified by selective medium, and dominant strains were selected. The dominant bacteria were cultured in the designated liquid medium to prepare the fermentation broths, and GABA in the fermentation broth was qualitatively screened out by thin-layer chromatography. The microbial fermentation broth with GABA spots in the primary screening was quantitatively detected by online pre-column derivatization and high performance liquid chromatography established in our laboratory. GABA-producing microorganisms were screened out from predominant strains, and their GABA contents in fermentation broth were determined. The DNA sequences of GABA-producing bacteria and fungi were amplified using 16S rDNA and 18S rDNA sequences by PCR respectively. The amplified products were sequenced, and the sequencing results were identified through NCBI homology comparison. Molecular biological identification was made by phylogenetic tree constructed by MEGA 7.0 software. Through the homology comparison of NCBI and the construction of phylogenetic tree by MEGA 7.0 software, nine GABA-producing microorganisms were screened out and identified in this study. They were Bacillus subtilis, Enterococcus faecium, E. avium, Aspergillus tamarii, A. flavus, A. niger, Cladosporium tenuissimum, Penicillium citrinum and Phanerochaete sordida respectively. For the first time, nine GABA-producing microorganisms were screened out and identified in the samples at different time points during the fermenting process of SSP in this study. The results indicated that multiple predominant GABA-producing microorganisms exist in the fermenting process of SSP and may play an important role in the formation of GABA.


Assuntos
Bactérias/classificação , Fermentação , Fungos/classificação , Ácido gama-Aminobutírico/biossíntese , Bactérias/metabolismo , Cromatografia Líquida de Alta Pressão , Fungos/metabolismo , Filogenia
7.
IEEE Trans Neural Netw Learn Syst ; 29(11): 5756-5760, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29994375

RESUMO

In this brief, the problem of delay-dependent stability of recurrent neural networks with time-varying delays is studied. A newly augmented Lyapunov-Krasovskii functional (LKF) that considers the information of the nonzero lower bound of time-varying delays is developed. Moreover, the information of the delayed state terms is not considered as elements of augmented vectors when constructing the LKF. An improved stability criterion with the framework of linear matrix inequalities is derived by employing the integral inequality and reciprocally convex combination. With the comparison to the existing ones, the developed stability criterion for neural networks has less conservatism and complexity. Finally, two widely used numerical examples are given to show the effectiveness and superiority of the obtained stability criterion.

8.
Methods Appl Fluoresc ; 5(2): 024014, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28475492

RESUMO

A new Al3+-specific fluorescent probe NQ was designed and synthesized from 2-hydroxy-1-naphthaldehyde and 2-aminoquinoline. Upon the addition of Al3+, the fluorescent intensity of NQ was significantly enhanced compared with other examined metal ions in aqueous solution. The result of a Job's plot indicated the formation of a 1:1 complex between the probe and Al3+, and the possible binding mode of the system between NQ and Al3+ was clarified by IR analysis and 1H NMR titration. Moreover, other metal ions examined had little effect on the detection of Al3+. The detection limit of NQ for Al3+ detection was 1.98 µM, which is lower than the level (7.4 µM) in drinking water defined by the World Health Organization. In addition, the fluorescent probe NQ could be recyclable simply through treatment with a proper reagent such as F-, and could also be used for the detection of Al3+ in real samples.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 173: 264-269, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27673495

RESUMO

A new p-dimethylaminobenzamide derivative based compound BDIH has been synthesized. Cu2+ turned on the fluorescence of compound BDIH with a 1:2 binding stoichiometry. The fluorescent color of compound BDIH shows an evident change from colorless to bright blue upon the addition of Cu2+, which could be visibly detected by the naked eye under UV light at 365nm. More importantly, the detection limit was found to be 0.64nM which is far lower than the maximal allowed concentration of the WHO limit (31.5µM) for drinking water. This selective "turn-on" fluorescence sensor was used to identify Cu2+ in living cells using confocal fluorescence microscopy, indicating that compound BDIH has a potential application for selective detection of Cu2+ in organism.


Assuntos
Benzaldeídos/química , Benzoatos/química , Cobre/análise , Hidrazinas/química , Indóis/química , Espectrometria de Fluorescência/métodos , Carcinoma Hepatocelular/química , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Humanos , Limite de Detecção , Neoplasias Hepáticas/química , Espectroscopia de Ressonância Magnética , Imagem Molecular/métodos , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
10.
ISA Trans ; 66: 233-240, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27773382

RESUMO

A control method based on global fast dynamic terminal sliding mode control (TSMC) technique is proposed to design the flight controller for performing the finite-time position and attitude tracking control of a small quadrotor UAV. Firstly, the dynamic model of the quadrotor is divided into two subsystems, i.e., a fully actuated subsystem and an underactuated subsystem. Secondly, the dynamic flight controllers of the quadrotor are formulated based on global fast dynamic TSMC, which is able to guarantee that the position and velocity tracking errors of all system state variables converge to zero in finite-time. Moreover, the global fast dynamic TSMC is also able to eliminate the chattering phenomenon caused by the switching control action and realize the high precision performance. In addition, the stabilities of two subsystems are demonstrated by Lyapunov theory, respectively. Lastly, the simulation results are given to illustrate the effectiveness and robustness of the proposed control method in the presence of external disturbances.

11.
Zhongguo Dang Dai Er Ke Za Zhi ; 18(6): 517-21, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-27324540

RESUMO

OBJECTIVE: To investigate the changes and clinical significance of biomarker fecal bile acids (BA) in children with Henoch-Schönlein purpura (HSP). METHODS: Nineteen children with HSP and twenty-seven healthy children were enrolled in this study. The stool samples were obtained at the acute and remission phases. Fecal BA levels were measured by high performance liquid chromatography mass spectrometry (HPLC-MS). RESULTS: The fecal cholic acid level in the HSP remission group was significantly higher than in the HSP acute group and the healthy control group (P<0.016). The fecal chenodeoxycholic acid level in the HSP remission group was significantly higher than in the healthy control group (P<0.016). The levels of fecal secondary colonic bile acids, deoxycholic acid and lithocholic acid, in the HSP acute and remission groups were significantly lower than in the healthy control group(P<0.05, P<0.016 respectively). No significant differences were found in the levels of fecal urosodeoxycholic acid among the three groups (P>0.05). CONCLUSIONS: Fecal secondary colonic bile acids, deoxycholic acid and lithocholic acid, are in decrease in children with HSP at the acute stage, which may be involved in the pathogenesis and treatment outcomes of HSP.


Assuntos
Ácidos e Sais Biliares/análise , Fezes/química , Vasculite por IgA/diagnóstico , Biomarcadores/análise , Criança , Feminino , Humanos , Vasculite por IgA/terapia , Masculino
12.
Anticancer Agents Med Chem ; 16(3): 387-92, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26265099

RESUMO

BACKGROUND AND AIM: The incidence of acute lymphoblastic leukemia (ALL) is highest in childhood malignant tumor in China. The high-dose methotrexate (HDMTX) treatment is very effective in ALL, and it can improve event-free survival rate. However, while executing the anti-tumor effect, it produces highly toxic effects on rapidly dividing cells which are normal. It seems probable that the HDMTX treatment injures intestinal mucosal barrier. The changes of intestinal mucosal barrier can be evaluated through measuring the level of plasma endotoxin and diamine oxidase (DAO). METHOD: Blood samples were collected from 30 normal children and 30 children with ALL at 1h, 24h, 44h and 68h after HDMTX. The levels of plasma endotoxin and DAO were measured at 1h, 24h, 44h and 68h after HDMTX with spectrophotometry. The levels of endotoxin and DAO were also measured in 4 different courses in 7 children with ALL. RESULTS: The levels of plasma endotoxin and DAO at 1h, 24h, 44h and 68h after HDMTX were higher than in normal children (P<0.01). The levels of plasma endotoxin and DAO at 24h and 44h after HDMTX were both higher than at 1h and 68h (P<0.01). There was no significant difference found in the measured results of plasma endotoxin and DAO at 1h and 68h after HDMTX (P>0.05). There was no significant difference found in the increased levels of endotoxin and DAO at 1h, 24h, 44h and 68h after HDMTX in 4 different courses of 7 children with ALL(P>0.05). CONCLUSION: By measuring the level of plasma endotoxin and DAO in children with ALL and during HDMTX chemotherapy, the results suggest that there is increased intestinal permeability.


Assuntos
Amina Oxidase (contendo Cobre)/sangue , Antimetabólitos Antineoplásicos/efeitos adversos , Endotoxinas/sangue , Mucosa Intestinal/efeitos dos fármacos , Metotrexato/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/uso terapêutico , Criança , Humanos , Lactente , Mucosa Intestinal/metabolismo , Teste do Limulus , Metotrexato/administração & dosagem , Metotrexato/uso terapêutico , Permeabilidade , Espectrofotometria , Taxa de Sobrevida
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(9): 910-3, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25229958

RESUMO

OBJECTIVE: To investigate the prevalence of childhood asthma, and to find the distribution characteristics, precipitating factors, diagnosis and treatment status, and to provide scientific data for improving the prevention and management of asthma in children in Kunming City, China. METHODS: Children were selected by random cluster sampling. A standardized preliminary questionnaire was used for screening out possible patients in the survey. Diagnosis of asthma was confirmed by diagnostic criteria in suspected asthmatic children. Asthmatic children were further asked for past diagnosis and treatment with the questionnaire of asthma in children. RESULTS: The total asthma incidence rate was 1.40%. The prevalence of asthma in male and female children was 1.89% and 0.88% respectively (P<0.05). Children aged 0-5 years old had a higher prevalence of asthma (1.69%) than that of school-age children (6-14 years old, 1.21%). In all asthmatic children, 51.3% were previously diagnosed with classical asthma or cough variant asthma, 26.0% were suffered attacks from December to February, and 54.0% were suffered attacks at midnight or dawn. Respiratory tract infection (87.3%) was the most common triggers of asthma exacerbation. Antibiotics were used in 80.0%, bronchodilators in 66.0%, inhaled corticosteroid in 64.0%. A peak flow meter for monitoring lung function was used in 17% of asthmatic children over 5 years old. CONCLUSIONS: The prevalence of asthma is associated with age and gender in children aged 0-14 years old in Kunming City. Acute asthma attack occurs mostly in winter and at midnight or dawn. Respiratory tract infection is the most common trigger of asthma exacerbation. Nearly a half of patients with asthma had not been diagnosed with asthma in the early stage. Most asthmatic children use antibiotics and only two-thirds use bronchodilators or inhaled corticosteroid in the treatment. The treatment and management of asthma in children awaits improvement as well.


Assuntos
Asma/epidemiologia , Adolescente , Asma/tratamento farmacológico , Asma/etiologia , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prevalência , Estações do Ano
14.
ISA Trans ; 53(4): 1350-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24751475

RESUMO

A method based on second order sliding mode control (2-SMC) is proposed to design controllers for a small quadrotor UAV. For the switching sliding manifold design, the selection of the coefficients of the switching sliding manifold is in general a sophisticated issue because the coefficients are nonlinear. In this work, in order to perform the position and attitude tracking control of the quadrotor perfectly, the dynamical model of the quadrotor is divided into two subsystems, i.e., a fully actuated subsystem and an underactuated subsystem. For the former, a sliding manifold is defined by combining the position and velocity tracking errors of one state variable, i.e., the sliding manifold has two coefficients. For the latter, a sliding manifold is constructed via a linear combination of position and velocity tracking errors of two state variables, i.e., the sliding manifold has four coefficients. In order to further obtain the nonlinear coefficients of the sliding manifold, Hurwitz stability analysis is used to the solving process. In addition, the flight controllers are derived by using Lyapunov theory, which guarantees that all system state trajectories reach and stay on the sliding surfaces. Extensive simulation results are given to illustrate the effectiveness of the proposed control method.

15.
ISA Trans ; 53(3): 725-31, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24534327

RESUMO

A synthesis control method is proposed to perform the position and attitude tracking control of the dynamical model of a small quadrotor unmanned aerial vehicle (UAV), where the dynamical model is underactuated, highly-coupled and nonlinear. Firstly, the dynamical model is divided into a fully actuated subsystem and an underactuated subsystem. Secondly, a controller of the fully actuated subsystem is designed through a novel robust terminal sliding mode control (TSMC) algorithm, which is utilized to guarantee all state variables converge to their desired values in short time, the convergence time is so small that the state variables are acted as time invariants in the underactuated subsystem, and, a controller of the underactuated subsystem is designed via sliding mode control (SMC), in addition, the stabilities of the subsystems are demonstrated by Lyapunov theory, respectively. Lastly, in order to demonstrate the robustness of the proposed control method, the aerodynamic forces and moments and air drag taken as external disturbances are taken into account, the obtained simulation results show that the synthesis control method has good performance in terms of position and attitude tracking when faced with external disturbances.

16.
Gastroenterol Res Pract ; 2012: 125890, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23243419

RESUMO

Aim. The study was to investigate the metabolic profile of urine metabolites and to elucidate their clinical significance in patients with colorectal cancer. Methods. Colorectal cancers from early stage and advanced stage were used in this study. Urine samples of colorectal cancer patients and healthy adults were collected and subjected to capillary electrophoresis mass spectrometry based on moving reaction boundary analysis. The metabolic data were analyzed by SPSS 17.0 to find urinary biomarkers for colorectal cancer. Results. The results indicated that the urine metabolic profiling of colorectal cancer patients had significant changes compared with the normal controls, and there were also differences between early stage and advanced colorectal cancer patients. Compared with the control group, the levels of isoleucine, valine, arginine, lactate acid and leucine increased (P < 0.05), but those of histidine, methionine, serine, aspartic acid, citric acid, succinate, and malic acid decreased in urine samples from colorectal cancer (P < 0.05). Furthermore, the levels of isoleucine and valine were lower in urine of patients with advanced colorectal cancer than those in early stage colorectal cancer (P < 0.05). Conclusion. The technique of capillary electrophoresis mass spectrometry based on MRB could reveal the significant metabolic alterations during progression of colorectal cancer, and the method is feasible and may be useful for the early diagnosis of colorectal cancer.

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