A Semi-supervised Nighttime Dehazing Baseline with Spatial-Frequency Aware and Realistic Brightness Constraint

Existing research based on deep learning has extensively explored the problem of daytime image dehazing. However, few studies have considered the characteristics of nighttime hazy scenes. There are two distinctions between nighttime and daytime haze. First, there may be multiple active colored light sources with lower illumination intensity in nighttime scenes, which may cause haze, glow and noise with localized, coupled and frequency inconsistent characteristics. Second, due to the domain discrepancy between simulated and real-world data, unrealistic brightness may occur when applying a dehazing model trained on simulated data to real-world data. To address the above two issues, we propose a semi-supervised model for real-world nighttime dehazing. First, the spatial attention and frequency spectrum filtering are implemented as a spatial-frequency domain information interaction module to handle the first issue. Second, a pseudo-label-based retraining strategy and a local window-based brightness loss for semi-supervised training process is designed to suppress haze and glow while achieving realistic brightness. Experiments on public benchmarks validate the effectiveness of the proposed method and its superiority over state-of-the-art methods. The source code and Supplementary Materials are placed in the https://github.com/Xiaofeng-life/SFSNiD.Comment: This paper is accepted by CVPR202

Fate of the distal aorta following root replacement in Marfan syndrome: a propensity score matched study

ObjectiveThe aortic root is the most frequent segment involved in Marfan syndrome. However, Marfan syndrome is a systemic hereditary connective tissue disorder, and knowledge regarding the outcomes of the native distal aorta after prophylactic aortic root surgery is limited.MethodsFrom April 2010 to December 2020, 226 patients with Marfan syndrome and 1,200 patients without Marfan syndrome who underwent Bentall procedures were included in this study. By propensity score matching, 134 patients were assigned to each group. Clinical manifestations and follow-up data were acquired from hospital records and telephone contact. The cumulative incidence of aortic events was estimated in Marfan and non-Marfan patients with death as a competing risk.ResultsPatients with and without Marfan syndrome had similar baseline characteristics after propensity score matching. Differences in the aortic root (62.25 ± 11.96 vs. 54.03 ± 13.76, P < .001) and ascending aorta (37.71 ± 9.86 vs. 48.16 ± 16.01, P < .001) remained after matching. No difference was observed in the frequency of aortic adverse events between the two groups (10.5% vs. 4.6%, P = 0.106). The cumulative incidence of aortic events was not different between Marfan and non-Marfan patients (15.03% ± 4.72% vs. 4.18% ± 2.06%, P = 0.147). Multivariate Cox regression indicated no significant impact of Marfan syndrome on distal aortic events (HR: 1.172, 95% CI: 0.263–5.230, P = 0.835). Descending and abdominal aortic diameter above normal at the initial procedure were associated with the risk of distal aortic events (HR: 20.735, P = .003, HR: 22.981, P = .002, respectively).ConclusionsNew-onset events of the residual aorta in patients undergoing Bentall procedures between the Marfan and non-Marfan groups were not significantly different. Distal aortic diameter above normal at initial surgery was associated with a higher risk of adverse aortic events

Efficacy and safety of stem cell therapy in cerebral palsy: A systematic review and meta-analysis

Aim: Although the efficacy and safety of stem cell therapy for cerebral palsy has been demonstrated in previous studies, the number of studies is limited and the treatment protocols of these studies lack consistency. Therefore, we included all relevant studies to date to explore factors that might influence the effectiveness of treatment based on the determination of safety and efficacy.Methods: The data source includes PubMed/Medline, Web of Science, EMBASE, Cochrane Library, from inception to 2 January 2022. Literature was screened according to the PICOS principle, followed by literature quality evaluation to assess the risk of bias. Finally, the outcome indicators of each study were extracted for combined analysis.Results: 9 studies were included in the current analysis. The results of the pooled analysis showed that the improvements in both primary and secondary indicators except for Bayley Scales of Infant and Toddler Development were more skewed towards stem cell therapy than the control group. In the subgroup analysis, the results showed that stem cell therapy significantly increased Gross Motor Function Measure (GMFM) scores of 3, 6, and 12 months. Besides, improvements in GMFM scores were more skewed toward umbilical cord mesenchymal stem cells, low dose, and intrathecal injection. Importantly, there was no significant difference in the adverse events (RR = 1.13; 95% CI = [0.90, 1.42]) between the stem cell group and the control group.Conclusion: The results suggested that stem cell therapy for cerebral palsy was safe and effective. Although the subgroup analysis results presented guiding significance in the selection of clinical protocols for stem cell therapy, high-quality RCTs validations are still needed

Location-Dependent Prediction of Dynamic Stability Limit for Peripheral Milling of Surfaces with Variable Curvatures

The stability limit may change with the cutter’s location due to effect of curvature during the milling of a complex surface. The method for calculating the actual radial cutting depth is presented by accounting for the effects of curvature on the actual cutting parameters. The computed radial cutting depth is in turn used to determine the entrance/exit angles. Moreover, a milling system dynamic model is established based on the instantaneous milling force coefficients, and the stability limit is determined by means of the time-domain semidiscretization method. In addition, a location-dependent method for predicting the stability associated with the peripheral milling of a complex surface is put forward and simulation is carried out to generate a stability limit diagram. The effectiveness of the proposed method is verified through milling tests

Location-Dependent Prediction of Dynamic Stability Limit for Peripheral Milling of Surfaces with Variable Curvatures

The stability limit may change with the cutter’s location due to effect of curvature during the milling of a complex surface. The method for calculating the actual radial cutting depth is presented by accounting for the effects of curvature on the actual cutting parameters. The computed radial cutting depth is in turn used to determine the entrance/exit angles. Moreover, a milling system dynamic model is established based on the instantaneous milling force coefficients, and the stability limit is determined by means of the time-domain semidiscretization method. In addition, a location-dependent method for predicting the stability associated with the peripheral milling of a complex surface is put forward and simulation is carried out to generate a stability limit diagram. The effectiveness of the proposed method is verified through milling tests

Role of Hydraulic Signal and ABA in Decrease of Leaf Stomatal and Mesophyll Conductance in Soil Drought-Stressed Tomato

Drought reduces leaf stomatal conductance (gs) and mesophyll conductance (gm). Both hydraulic signals and chemical signals (mainly abscisic acid, ABA) are involved in regulating gs. However, it remains unclear what role the endogenous ABA plays in gm under decreasing soil moisture. In this study, the responses of gs and gm to ABA were investigated under progressive soil drying conditions and their impacts on net photosynthesis (An) and intrinsic water use efficiency (WUEi) were also analyzed. Experimental tomato plants were cultivated in pots in an environment-controlled greenhouse. Reductions of gs and gm induced a 68–78% decline of An under drought conditions. While soil water potential (Ψsoil) was over −1.01 MPa, gs reduced as leaf water potential (Ψleaf) decreased, but ABA and gm kept unchanged, which indicating gs was more sensitive to drought than gm. During Ψsoil reduction from −1.01 to −1.44 MPa, Ψleaf still kept decreasing, and both gs and gm decreased concurrently following to the sustained increases of ABA content in shoot sap. The gm was positively correlated to gs during a drying process. Compared to gs or gm, WUEi was strongly correlated with gm/gs. WUEi improved within Ψsoil range between −0.83 and −1.15 MPa. In summary, gs showed a higher sensitivity to drought than gm. Under moderate and severe drought at Ψsoil ≤ −1.01 MPa, furthermore from hydraulic signals, ABA was also involved in this co-ordination reductions of gs and gm and thereby regulated An and WUEi

Influence of Aggregate Pollution in Truck Escape Ramps on Stopping Distance of Uncontrolled Vehicles

Migration of fine materials such as soil from the roadbed and the ground will gradually pollute the aggregate in the arrester bed of truck escape ramps. However, there are few studies on the impact of aggregate pollution of the arrester bed on the stopping distance of runaway vehicles. This paper uses the discrete element method to study the influence of aggregates with different degrees of pollution on stopping distance by taking silty cohesive soil as a typical pollutant. In this paper, the stopping process of the uncontrolled vehicle on the arrester bed with different pollution levels was numerically simulated. The simulation results show that the uncontrolled vehicle’s stopping distance increases with the contaminated aggregate’s soil content. The simulation results show that when the soil content in the contaminated aggregate is less than 15%, the increase in the stopping distance of the uncontrol vehicle is less than 5%; when the soil content is 20–25%, the stopping distance of the uncontrolled vehicle increases by more than 20%; and when the soil content is 30–35%, the stopping distance of uncontrol vehicle increases by more than 50%. Different maintenance measures should be taken according to the increase in stopping distance

Influence of Aggregate Pollution in Truck Escape Ramps on Stopping Distance of Uncontrolled Vehicles

Migration of fine materials such as soil from the roadbed and the ground will gradually pollute the aggregate in the arrester bed of truck escape ramps. However, there are few studies on the impact of aggregate pollution of the arrester bed on the stopping distance of runaway vehicles. This paper uses the discrete element method to study the influence of aggregates with different degrees of pollution on stopping distance by taking silty cohesive soil as a typical pollutant. In this paper, the stopping process of the uncontrolled vehicle on the arrester bed with different pollution levels was numerically simulated. The simulation results show that the uncontrolled vehicle’s stopping distance increases with the contaminated aggregate’s soil content. The simulation results show that when the soil content in the contaminated aggregate is less than 15%, the increase in the stopping distance of the uncontrol vehicle is less than 5%; when the soil content is 20–25%, the stopping distance of the uncontrolled vehicle increases by more than 20%; and when the soil content is 30–35%, the stopping distance of uncontrol vehicle increases by more than 50%. Different maintenance measures should be taken according to the increase in stopping distance

Direct Liquefaction of Bamboo in Ethanol-Phenol Co- Solvent

Bamboo was converted into bio-oil via direct liquefaction with ethanol-phenol as solvent in a 250 mL Parr High-Pressure reactor. The influences of reaction parameters such as reaction time, liquefaction temperature, catalyst content, ratio of solvent/bamboo, and phenol concentration on the liquefaction yield were investigated. The highest liquefaction yield was 98.5 wt.% under the optimal conditions. The elemental analysis of the produced bio-oil revealed that the oil product had a higher heating value (HHV) of 29.5 MJ/kg, which was much higher than that of the raw material (16.4 MJ/kg). Gas chromatography mass spectrometry (GC-MS) and Fourier transform infrared spectrometry (FT-IR) measurements showed that the main volatile compounds in the crude bio-oil were phenolics and esters