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1.
Heliyon ; 10(11): e31975, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38882282

RESUMO

Takeover is a critical factor in the safety of autonomous driving. Takeover refers to the action of a human driver assuming control of an autonomous vehicle from its automated driving system. This can occur when the vehicle encounters a situation it cannot handle, when the system requests the driver to take control, or when the driver chooses to intervene for safety or other reasons. This study explored how traditional steering-wheel driving habits affect takeover performance in joystick-controlled autonomous vehicles. We conducted an experiment using a joystick-controlled Dongfeng Sharing-VAN autonomous vehicle in a low-speed campus environment. The participants were divided into three groups based on their driving experience: the individuals who have no licence and no experience (NN Group), the drivers who have licence but not experienced (HN Group), and the drivers who have licence and have been experienced (HH Group), representing varying levels of driving habits. The experiment focused on two takeover tasks: passive takeover and active takeover. We evaluated takeover performance using takeover time and takeover quality as key metrics. The results from the passive takeover task indicated that traditional driving habits had a significant negative impact on takeover performance. The HH Group took 2.65 s longer to complete the task compared to the NN Group, while the HN Group took 3.78 s longer. When we analyzed takeover time in stages, the initial stage showed the most significant difference in takeover time among the three groups. In the active takeover task, driving habits did not significantly affect takeover braking in front of obstacles in a low-speed driving environment. These findings suggest that conventional driving habits can hinder passive takeover in joystick-controlled autonomous vehicles. This insight can be valuable for developing training programs and guidelines for drivers transitioning from conventional to autonomous driving.

2.
Br J Ophthalmol ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777388

RESUMO

AIMS: To investigate the effect of preretinal tractional structures (PTS) and posterior scleral structures (PSS) on myopic traction maculopathy (MTM) progression. METHODS: This retrospective cohort study included 185 fellow highly myopic eyes of 185 participants who underwent surgery for MTM. PTS included epiretinal membrane, incomplete posterior vitreous detachment and their combination. PSS included posterior staphyloma and dome-shaped macula (DSM). The MTM stage was graded according to the Myopic Traction Maculopathy Staging System. Optical coherence tomography was used to identify MTM progression, defined as an upgrade of MTM. The Kaplan-Meier method with log-rank test was used to assess MTM progression over the 3-year follow-up period. Risk factors for progression were identified using Cox regression analysis. RESULTS: MTM progression was observed in 48 (25.9%) eyes. Three-year progression-free survival (PFS) rates for eyes with PTS, staphyloma and DSM were 53.7%, 58.2% and 90.7%, respectively. Eyes with PTS and staphyloma exhibited lower 3-year PFS rates than those without PTS or staphyloma (P log-rank test =0.002 and <0.001), while eyes with DSM had a higher 3-year PFS rate than eyes without DSM (P log-rank test=0.01). Multivariate Cox regression analysis showed that PTS (HR, 3.23; p<0.001) and staphyloma (HR, 7.91; p<0.001) were associated with MTM progression, whereas DSM (HR, 0.23; p=0.046) was a protective factor. CONCLUSION: Both PTS and PSS play a critical role in the progression of MTM. Addressing these factors can aid in the management of MTM.

3.
BMC Ophthalmol ; 23(1): 92, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894878

RESUMO

BACKGROUND: To report a rare case of IgG4-related ophthalmic disease (IgG4-ROD) manifesting as intraocular masses and scleritis in both eyes in a 61-year-old male and to investigate the changes in multimodal imaging features of the lesion sites and helper T-cell type 1 (Th 1)/Th 2/Th 17 cytokine levels in the aqueous humor. CASE PRESENTATION: A patient with IgG4-ROD seemingly manifested with an intraocular tumor in the left eye and sequentially, with an inflammatory mass in the ciliary body and scleritis in the right eye. The patient complained of vision loss of 6 months duration in the left eye at his first visit. With a preliminary diagnosis of an intraocular tumor, enucleation of the left eyeball and histopathological examination were performed. Approximately 3 months later, the patient started to experience headache, eye pain, and declining vision in the right eye. Ophthalmic imaging revealed a ciliary mass and scleritis. Th 1/Th 2/Th 17 cytokine levels and multimodal imaging findings were analyzed before and after corticosteroid treatment. Histopathological examination and immunohistochemistry (IHC) of the enucleated left eye demonstrated lymphoplasmacytic infiltration with an IgG4+/IgG+ cell ratio of approximately 40%, pointing to the diagnosis of probable IgG4-ROD. Long-term treatment with corticosteroids led to significant improvement in the signs and symptoms of the left eye. Th 1/Th 2/Th 17 cytokine profile monitoring of the aqueous humor and multimodal imaging of the right eye showed gradual regression of the mass and attenuation of ocular inflammation during treatment. CONCLUSIONS: Patients with an atypical presentation of IgG4-ROD, such as intraocular masses and scleritis, are likely to experience a significant delay in diagnosis. This case demonstrates the significance of IgG4-ROD in the differential diagnosis of intraocular tumors and ocular inflammation. IgG4-RD is a newly diagnosed disease with multi-organ involvement and little is known about its pathogenesis, particularly in the eye. The present case will open new challenges in the clinico-pathological diagnosis and research of this disease. Combined investigations of multimodal imaging and cytokine level detection of intraocular fluid provide a new and effective way to monitor disease progression.


Assuntos
Doença Relacionada a Imunoglobulina G4 , Esclerite , Neoplasias Uveais , Masculino , Humanos , Pessoa de Meia-Idade , Esclerite/diagnóstico , Doença Relacionada a Imunoglobulina G4/patologia , Corpo Ciliar/patologia , Neoplasias Uveais/diagnóstico , Corticosteroides , Inflamação , Imunoglobulina G
4.
J Clin Med ; 11(13)2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35807191

RESUMO

This study compared the absorption of subretinal fluid (SRF) in patients with rhegmatogenous retinal detachment (RRD) with and without high myopia after scleral buckling (SB) and investigated the effect of high myopia on SRF absorption. This retrospective study included patients with primary macula-off RRD grouped according to myopia and age. The optical coherence tomography (OCT) and OCT angiography indicators included subretinal fluid height (SRFH), subfoveal choroidal thickness (SFCT), and choroidal capillary blood flow density (CCFD) measured regularly. The presence of SRF 3 months after surgery was defined as delayed absorption. Overall, 90 eyes of 89 patients were enrolled, and 46 eyes (51.11%) had high myopia. In 43 eyes (47.78%), SRF absorption was delayed. There was no significant difference in SRF absorption after SB between the high and non-high myopia groups; younger patients (<35 years) had a higher probability of delayed absorption (p < 0.05). The SFCT in high myopia was significantly thinner than that in the non-high myopia group (p < 0.05); SFCT and SRFH were positively correlated (rs = 0.275, p = 0.002), and there was a significant difference between the average CCFD with and without SRF (p < 0.05). High myopia had no significant effect on SRF absorption after SB.

5.
PLoS One ; 16(12): e0260977, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34882717

RESUMO

Ramp metering on freeway is one of the effective methods to alleviate traffic congestion. This paper advances the field of freeway ramp metering by introducing an application to the on-ramp, capitalizing on the macro traffic follow theory and improved the freeway traffic flow. The Particle Swarm Optimization (PSO) based on Proportional Integral Derivative (PID) controller is further developed to single ramp metering as well as to optimize the PID parameters. The approach is applied to a case study of the Changyi Freeway(G5513) in Hunan, China. The simulation is conducted by applying the actual profile traffic data to PID controller to adjust the entering traffic flow on the freeway on-ramp. The results show that the PSO-PID controller tends to converge in about 80 minutes, and the density tends to be stable after 240 iterations. The system has smaller oscillation, more accurate adjustment of ramp regulation rate, and more ideal expected traffic flow density. The traffic congestion on mainline is effectively slowed down, traffic efficiency is improved, and travel time and cost are reduced. The nonlinear processing ability of PSO-PID controller overcomes the defects of the traditional manual closing ramp, and can be successfully applied in the field of intelligent ramp metering.


Assuntos
Acidentes de Trânsito/prevenção & controle , Algoritmos , Condução de Veículo/estatística & dados numéricos , Simulação por Computador , Humanos , Segurança
6.
Accid Anal Prev ; 159: 106271, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34218197

RESUMO

The time-to-collision (TTC) index and its extended variants have been widely utilized to assess rear-end collision risks, but the characteristics of the time-series data have not been fully explored, especially for the transition from safe to risky conditions. This study proposes a novel approach in rear-end collision risk analysis based on the concept of transition durations. The vehicle trajectory data were extracted and the TTC index was used to identify risky and safe conditions. Three important transition durations are defined and their rationalities for evaluating rear-end collision risks are examined by developing random-parameters accelerated failure time (AFT) survival models. Furthermore, a typical case from real trajectory data is taken to discuss the limitations of using TTC and its variants, and the advantage of the proposed transition durations. The results of random-parameters AFT models reveal contributing factors affecting the length of three durations and demonstrate the rationality of transition durations in rear-end collision risks analysis. It is indicated that the proposed method outperforms TTC and its variants in evaluating rear-end collision risks, because it could not only provide the information of time point but also the variation of time-series data.


Assuntos
Condução de Veículo , Acidentes de Trânsito , Humanos , Medição de Risco
7.
BMC Ophthalmol ; 21(1): 86, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588767

RESUMO

BACKGROUND: The purpose of this study is to assess the absorption of subretinal fluid (SRF) after scleral buckling (SB) surgery for the treatment of rhegmatogenous retinal detachment (RRD). We also examined related factors that may affect the delayed absorption of SRF. METHODS: This retrospective study included patients who underwent successful SB surgery for the treatment of macula-off RRD and in which the retina was reattached after the surgery. The patients were categorized according to gender, duration, age, the number, and location of retinal breaks. Subfoveal choroidal thickness (SFCT), height of subretinal fluid (SRFH), and the choriocapillaris flow density (CCFD) within 3 × 3 mm macular fovea were included. Delayed absorption was determined by the SRF that remained unabsorbed for 3 months after the procedure. The endpoint was determined when the SRF could no longer be observed. RESULTS: A total of 62 patients (63 eyes) were enrolled. In 35 eyes (56.45%) SRF was completely absorbed and in 28 (43.55%) eyes delayed absorption of SRF in macular areas was observed at 3 months after surgery. A young age (< 35 years), inferior retinal breaks were associated with good outcomes by applying multivariable analysis on the rate of SRF absorption after SB instead of gender, the number of breaks, and duration (p < 0.05). CCFD was significantly different between the SRF group and the non-SRF group after SB (0.66 ± 0.04% vs 0.63 ± 0.05%, P < 0.05). SRFH showed a moderate positive correlation with SFCT (rs = 0.462, p = 0.000), however, using binary logistic regression analysis it was determined that SFCT was not related to the absorption of the SRF. CONCLUSIONS: The absorption of SRF after SB may be correlated with choriocapillaris flow density. Age and location of breaks are significant factors affecting the absorption of SRF. The duration of disease is an uncertain factor due to several subjective reasons.


Assuntos
Descolamento Retiniano , Recurvamento da Esclera , Líquido Sub-Retiniano , Adulto , Feminino , Humanos , Masculino , Descolamento Retiniano/cirurgia , Estudos Retrospectivos , Recurvamento da Esclera/efeitos adversos , Tomografia de Coerência Óptica
8.
BMC Ophthalmol ; 20(1): 382, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32977791

RESUMO

BACKGROUND: Varying degrees of macular ischemia generally occur in diabetic retinopathy (DR). This study aims to evaluate the effect of conbercept with 3+ pro re nata (PRN) on macular perfusion status in patients with diabetic macular edema (DME) and quantitatively assess changes in foveal avascular zone (FAZ) areas and capillary density in macular regions by applying optical coherence tomography angiography (OCTA). METHODS: Fifty patients were divided into ischemic (n = 31) and non-ischemic (n = 19) groups according to the presence of ischemia on OCTA at baseline. All patients received intravitreal injections of 0.5 mg of conbercept with 3+ PRN principle. The FAZ areas and macular vessel density measured using OCTA were evaluated at baseline, 3 months, and 6 months after treatment in both groups. RESULTS: At months 3 and 6, the FAZ area in the ischemic group changed from 0.510 ± 0.171 mm2 to 0.441 ± 0.158 mm2 then to 0.427 ± 0.153 mm2 (p = 0.003, p = 0.296); in the non-ischemic group, it remained stable (p = 0.269, p = 0.926). The superficial vessel density changed from 41.1 ± 4.1 to 42.5% ± 4.7% then to 42.6% ± 4.6% (p = 0.043, p = 0.812), and the deep vessel density changed from 40.7 ± 4.4 to 42.3% ± 3.6% then to 42.3% ± 4.7% (p = 0.072, p = 0.961) in the ischemic group. In the non-ischemic group, the superficial vessel density changed from 44.8 ± 3.2 to 46.0% ± 3.5% then to 45.7% ± 3.3% (p = 0.108, p = 0.666), whereas the deep vessel density changed from 43.6 ± 3.6 to 43.8% ± 3.2% then to 43.5% ± 4.5% (p = 0.882, p = 0.736). Reperfusion in macular nonperfusion areas was observed. CONCLUSION: Anti-vascular endothelial growth factor treatment may have a positive effect on macular perfusion status. Furthermore, OCTA had advantages in quantifying and calculating blood flow index in the study of macular perfusion status.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/tratamento farmacológico , Angiofluoresceinografia , Humanos , Isquemia/tratamento farmacológico , Edema Macular/diagnóstico , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Proteínas Recombinantes de Fusão , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica , Acuidade Visual
9.
BMC Ophthalmol ; 19(1): 150, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311513

RESUMO

BACKGROUND: Morning glory syndrome is a relatively rare congenital optic disc anomaly that is often difficult to identify when associated with additional congenital ocular anomalies. This case report describes the diagnosis, treatment, and postoperative follow-up care of a young girl with morning glory syndrome accompanied by persistent fetal vasculature, retinal fold, and retinal detachment. Here, we also give a brief review of the relevant literature. CASE PRESENTATION: A 5-year-old girl was referred to our clinic for a complaint of decreased vision for 6 months in the right eye. The best corrected visual acuity was hand motion in her right eye and 0.8 in her left eye. A fundus examination indicated vitreous opacities and scattered hemorrhages, as well as striped folds in the temporal retina of the affected eye. B-ultrasound and magnetic resonance imaging scans suggested that it could be a congenital dysplasia of the right eye. Pars plana vitrectomy was performed in the right eye. Morning glory syndrome associated with persistent fetal vasculature was confirmed in subsequent follow-up observation according to the fundus appearance, optical coherence tomography, and fundus fluorescein angiography imaging. CONCLUSIONS: The patient was diagnosed as morning glory syndrome associated with persistent fetal vasculature and retinal fold. The morning glory disc with the presence of retinal folds did not seem quite typical and that made the diagnosis difficult. This report stresses the importance of considering concurrent morning glory syndrome and persistent fetal vasculature. Vitrectomy may be beneficial in the management of the morning glory syndrome and persistent fetal vasculature if accompanied by retinal detachment in similar cases.


Assuntos
Disco Óptico/anormalidades , Nervo Óptico/anormalidades , Vítreo Primário Hiperplásico Persistente , Descolamento Retiniano , Pré-Escolar , Feminino , Humanos , Vítreo Primário Hiperplásico Persistente/diagnóstico , Vítreo Primário Hiperplásico Persistente/cirurgia , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/cirurgia , Resultado do Tratamento , Vitrectomia/métodos
10.
Traffic Inj Prev ; 12(5): 538-44, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21972865

RESUMO

OBJECTIVES: Few studies have focused on the effect of countdown timers at signalized intersections in China, where such timers are widely deployed for their perceived benefits of increased safety and capacity. This study examines the effect of countdown timers on driver behavior during the yellow interval. METHOD: Signal phasing and traffic operations were videotaped at 4 comparable signalized intersections under normal conditions. Microscopic details were extracted manually at 25 Hz to yield 24 h of data on onset time of the yellow, onset time of the red, driver location and actions after the onset of the yellow, red light-running violations, etc. For comparable intersections with and without countdown timers, driver behavior measured by driver decision (stop or go) and vehicle entry time (when the vehicle crosses the stop line) were analyzed using binary logistical regression (BLR) and a nonparametric test, respectively. RESULTS: The results suggest that countdown timers can indeed influence driver behaviors, in terms of decisions to stop or cross the intersection as well as the distribution of vehicle entry times. There was a strong correlation between the presence of countdown timers and an increase in red light violations. CONCLUSION: Countdown timers may lead to increased entrance into the intersection during the later portions of the yellow and even the red. This alarming finding calls for further research as well as for serious consideration before the field deployment of countdown timers.


Assuntos
Condução de Veículo/psicologia , Comportamento Perigoso , Tomada de Decisões , Planejamento Ambiental , Condução de Veículo/legislação & jurisprudência , China , Humanos , Segurança , Fatores de Tempo , Gravação de Videoteipe
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