Ecotoxicological risk of asphalt pavements to aquatic animals associated with pollutant leaching.

Contaminants such as heavy metals and polycyclic aromatic hydrocarbons (PAHs) can be released from asphalt pavement and transported through stormwater runoff to nearby water bodies, leading to water pollution and potential harm to living aquatic animals. This study characterizes the heavy metal and PAH leaching from various asphalt paving materials and their potential ecotoxicological effects on zebrafish Danio rerio. Artificial runoffs were prepared in the laboratory concerning the effects of water, temperature, and traffic. The concentrations of heavy metals and PAHs in the leachates were quantified, while the toxicity assessment encompassed mortality, metal stress, PAH toxicity, inflammation, carcinogenicity, and oxidative damage. Gene expressions of related proteins or transcription factors were assessed, including metallothionines, aryl hydrocarbon receptors, interleukin-1ß, interleukin-10, nuclear factor-κB, tumor necrosis factor-α, tumor suppressor p53, heat shock protein 70, and reactive oxygen species (ROS). The findings demonstrate that leachates from asphalt pavements containing waste bottom ash, crumb rubber, or specific chemicals could induce notable stress and inflammation responses in zebrafish. In addition, potential carcinogenic effects and the elevation of ROS were identified within certain treatment groups. This study represents the first attempt to assess the ecotoxicity of pavement leachates employing a live fish model, thereby improving the current understanding of the environmental impact of asphalt pavements.

Three-dimensional image authentication from multi-view images.

Three-dimensional (3D) optical authentication is important for modern information security. Existing 3D optical authentication methods rely on integral imaging devices, necessitating meticulous calibration and incurring high transmission overhead. To streamline the acquisition of 3D information, this paper introduces a novel 3D optical authentication approach, to the best of our knowledge, based on the construction of 3D data from multi-view images. The proposed method simplifies 3D projection by generating fixed-viewpoint elemental images, eliminating the need for additional viewpoint information during transmission and authentication. Compressed sensing is used for compression during transmission, and a deep learning network is designed for 3D reconstruction, enhancing the recovery. Experimental outcomes confirm the efficiency of our proposed approach for 3D authentication across diverse datasets.

Leaching characteristics of metals and Polycyclic Aromatic Hydrocarbons (PAHs) from asphalt paving materials.

Asphalt pavement, a major type of road surface, may contain hazardous elements depending on its specific composition. A growing concern has developed regarding the potential leaching of these hazardous constituents from asphalt pavements, particularly when incorporating waste materials and additives. This study investigates the presence of heavy metals and polycyclic aromatic hydrocarbons (PAHs) in leachates from six commonly employed asphalt paving materials. A comprehensive laboratory leaching experiment was conducted on three key sample scales: asphalt binder, asphalt mortar, and asphalt mixture. The impact of the leachates was assessed by the heavy metal pollution index and the toxic equivalency factor based on the benzo[a]pyrene equivalent concentration. The results reveal that leaching tests at the binder and mortar scales provided fundamental insights into leaching characteristics within a relatively short timeframe, while the mixture-scale test was more capable of representing pollutant leaching in near-true scenarios. In addition, the results indicate potential adverse health implications associated with the incorporation of hazardous waste, such as bottom ash, into asphalt pavement. These findings hold significant implications for promoting environmentally responsible practices of asphalt pavement.

Kinetics and toxicological potential of heavy metal leaching from asphalt pavements.

The leaching of heavy metals from asphalt pavement has attracted increasing attention due to its associated environmental risks. Comprehending the leaching process is crucial for ensuring the safe utilization of asphalt pavement. This study investigates heavy metal leaching kinetics from asphalt pavements using tank-leaching tests and dynamic simulations employing both first and second-order kinetic models. Furthermore, this study reveals the toxicological potential of heavy metal leaching from asphalt pavement by assessing its temporal metal accessibility based on the obtained kinetic attributes. Six distinct asphalt mixtures were prepared and tested, each exhibiting two different gradations. The findings demonstrated that both kinetic models effectively elucidated the leaching process. Notably, the relatively stable final leaching stages primarily adhered to first-order kinetics, while the second-order kinetics provided a superior description of the more intricate initial leaching stages. In terms of toxicological potential, the results indicated that recycled waste-incorporated asphalt pavements, specifically bottom ash-incorporated asphalt and asphalt rubber, exhibited excessive heavy metal leaching for varying durations, ranging from several days to months under specific conditions. This study has provided valuable insights into the metal leaching kinetics of asphalt pavements and their associated toxicological impact, significantly advancing the current understanding of the consequences of heavy metal leaching from asphalt pavements.

Cascade light field disparity estimation network based on unsupervised deep learning.

Light field disparity estimation is an important task in light field applications. However, how to efficiently utilize the high-dimensional light field data is a very worthy issue to investigate. Besides, existing supervised deep learning based algorithms are limited to scenes with ground truth disparity for training. In this paper, we propose a light field disparity estimation network which adopts a cascade cost volume architecture and can predict disparity maps in a coarse to fine manner by fully exploring the geometry characteristics of sub-aperture images. In addition, we design a combined unsupervised loss to train our network without a ground truth disparity map. Our combined loss consists of occlusion-aware photometric loss and edge-aware smoothness loss which can bring targeted performance improvements in occlusion and textureless regions, respectively. Extensive experiments demonstrate that our approach can achieve better results compared to existing unsupervised disparity estimation method and show better generalizability compared to supervised methods.

Three-dimensional image authentication with double random phase encryption in one capture.

We propose a new, to the best of our knowledge, three-dimensional (3D) authentication method based on double random phase integral imaging, and only one image at one viewpoint is used during the authentication process. Two neural networks are applied to estimate depth information and the inpainted synthesized viewpoint image. The usage of deep learning and geometric refocusing techniques greatly simplifies the whole authentication process including capture, transmission, and storage. Experimental results verify the presented method and successfully prove the developed 3D authentication process using a nonlinear correlation method.

Effect of Reclaimed Asphalt Pavement Heating Temperature on the Compactability of Recycled Hot Mix Asphalt.

The compactability of an asphalt mixture is related to the heating temperature of the materials, but the heating temperature of reclaimed asphalt pavement (RAP) is limited by the production process of hot-in-plant recycled mixtures. To choose a reasonable heating temperature for RAP according to the compactability, the compaction energy ratio (CER) obtained from the Superpave gyratory compactor compaction curve was developed. The CERs of fourteen kinds of asphalt mixtures made with different RAPs were compared, all of which were different in type, content, and heating temperature. The results indicated that CER is an effective energy index to evaluate the workability of a bituminous mixture, and it considers both the accumulated energy after each gyration and the number of gyrations. It was also found that increasing the heating temperature of the RAP cannot always improve the workability of the recycled mixture, because the higher heating temperature caused more hard-aged bitumen to be blended with soft virgin bitumen during the mixing process. At the same RAP heating temperature, increasing the RAP content made it more difficult to compact the mixture, especially for RAPs with styrene-butadiene-styrene (SBS) modified bitumen, and the recycled mixtures with SBS-modified bitumen were more difficult to compact than those with nonmodified bitumen.

Accurate Initial State Estimation in a Monocular Visual-Inertial SLAM System.

The fusion of monocular visual and inertial cues has become popular in robotics, unmanned vehicles and augmented reality fields. Recent results have shown that optimization-based fusion strategies outperform filtering strategies. Robust state estimation is the core capability for optimization-based visual-inertial Simultaneous Localization and Mapping (SLAM) systems. As a result of the nonlinearity of visual-inertial systems, the performance heavily relies on the accuracy of initial values (visual scale, gravity, velocity and Inertial Measurement Unit (IMU) biases). Therefore, this paper aims to propose a more accurate initial state estimation method. On the basis of the known gravity magnitude, we propose an approach to refine the estimated gravity vector by optimizing the two-dimensional (2D) error state on its tangent space, then estimate the accelerometer bias separately, which is difficult to be distinguished under small rotation. Additionally, we propose an automatic termination criterion to determine when the initialization is successful. Once the initial state estimation converges, the initial estimated values are used to launch the nonlinear tightly coupled visual-inertial SLAM system. We have tested our approaches with the public EuRoC dataset. Experimental results show that the proposed methods can achieve good initial state estimation, the gravity refinement approach is able to efficiently speed up the convergence process of the estimated gravity vector, and the termination criterion performs well.

The Development of the Chinese Intermittent Exotropia Questionnaire.

PURPOSE: The Intermittent Exotropia Questionnaire (IXTQ) is a child, proxy, and parent report of health-related quality of life specific to children with intermittent exotropia (IXT). The present study aimed to develop a Chinese-language version of the IXTQ (CIXTQ) and evaluate its validity and reliability when used in Chinese IXT children and their parents. METHODS: The IXTQ was translated into Chinese. One hundred seventy-five IXT children (2 to 17 years old) and 151 orthotropic control children (2 to 17 years old) along with one of their parents were recruited. Children 5 to 17 years old completed the 5- to 7-year-old or the 8- to 17-year-old child questionnaire of the CIXTQ according to their age. Parents of all children (2 to 17 years old) completed the proxy and parent questionnaires of the CIXTQ. Psychometric properties of the CIXTQ were examined for floor and ceiling effects, construct validity, item-internal consistency, discriminative validity, Cronbach α coefficient and test-retest reliability. RESULTS: No items were found to have strong floor or ceiling effects. Principal component analysis identified that the CIXTQ had a similar structure to the original English version. The median scores of each questionnaire in the CIXTQ among children with IXT and their parents were significantly lower than those among control subjects (P < .001). Cronbach α coefficients ranged from 0.869 to 0.931, and test-retest reliabilities ranged from 0.898 to 0.981, for each questionnaire in the CIXTQ. CONCLUSIONS: The CIXTQ is a useful tool to evaluate the influence of IXT on health-related quality of life among Chinese IXT children and their parents.

Preoperative prediction of papillary thyroid microcarcinoma via multiparameter ultrasound.

Background Accurate diagnosis of papillary thyroid microcarcinoma (PTMC) is important for further management. Ultrasound (US) is the most frequently used imaging modality for PTMC. Purpose To evaluate the diagnostic value of conventional US, contrast-enhanced ultrasound (CEUS) and real-time elastography (RTE) for patients with PTMC. Material and Methods In total, 135 patients with subcentimeter thyroid nodules who underwent conventional US, CEUS, and RTE before surgery were enrolled. A multivariate logistic regression analysis was performed to assess the independent predictors of PTMC. The diagnostic performances of conventional US, CEUS, and RTE were evaluated with a receiver operating characteristic (ROC) curve analysis. Results A taller-than-wide shape was identified as the strongest predictor of PTMC (odds ratio [OR], 25.21), followed by heterogeneous enhancement (OR, 24.03), marked hypoechogenicity (OR, 21.71), poorly defined margin (OR, 5.51), strain ratio (OR, 2.59), and age (OR, 0.92; all P values < 0.05). Heterogeneous enhancement on CEUS showed the highest positive predictive value (PPV; 88.0%) and an accuracy of 83.7%. A logistic regression model was created to predict PTMC using conventional US, CEUS, and RTE. The area under the ROC curve was 0.97, with a sensitivity of 88.6% and a specificity of 94.6%. Conclusion Conventional US combined with CEUS and RTE can improve the diagnostic accuracy of PTMC.

Evaluation of spasticity after stroke by using ultrasound to measure the muscle architecture parameters: a clinical study.

OBJECTIVE: This study aims to compare the difference and the change trend of Muscle Architecture Parameters (MAP) between spastic and normal muscle tone patients after stroke, and analysis the application and value of Muscle Architecture Parameters in evaluating spasticity after stroke. METHODS: 41 stroke patients were divided into spastic group (26 cases), normal muscle tone control group (15 cases). Modified Ashworth Scale (MAS) was applied in both groups for assessing muscle tone of lower limbs (no influence, contralateral). Muscle architectural parameters of ultrasound measurement include muscle thickness, fascicle length and pennation angle. The difference of three muscle architectural parameters between the affected side and the contralateral side in spastic group and the difference of MAS and three muscle architectural parameters between spastic group and normal control group were compared. RESULTS: MAS score, Pennation Angle (PA) and Muscular Thickness (MT) value of MAP in spastic group were significantly higher than the control group, Fascicle length (FL) is significantly lower than the control group (P < 0.05). In spastic group, MAS score, PA and MT value of MAP of affected side muscle was substantially higher than that of contralateral, FL value significantly lower than that of contralateral (P < 0.05). There was positive correlation between MAS and PA and MT but was negative correlation between MAS and FL, rank correlation coefficient test was statistical significant (p < 0.05). Logistic multivariate regression analysis showed that spasticity can lead PA and FL to change (p < 0.05), there is no clear correlation between MT and spasticity occurs (P > 0.05). CONCLUSION: MAP has a better sensitivity in evaluating muscle tone between spastic patients and non-spastic patients, and degrees of spasticity have a clear corresponding exponential relationship to MAP. Combing MAS and MAP can assess muscle tone more objectively and accurately because subtle changes can be observed by testing values of architecture parameters that compensating for the shortcomings of MAS in reliability and validity. Thus it is helpful for guiding clinical antispastic practice.

Polyamidoamine dendrimer conjugated chitosan nanoparticles for the delivery of methotrexate.

Encapsulating anticancer drugs to synthetic polymer is a promising approach to improve the efficiency and reduce the side effects of anticancer drugs. In this study, novel chitosan derivatives with polyamidoamine moieties (CS-PAMAM) were synthesized and characterized by morphology, particle size, and zeta potential. Then the anticancer drug-methotrexate-encapsulated CS-PAMAM was prepared by hydrophobic-hydrophilic interactions. The drug release assay showed that the amount of the methotrexate release from CS-PAMAM was pH depended. Meanwhile, the cell viability assay illustrated that CS-PAMAM was suitable for the drug delivery because of its low cytotoxicity on cells. Moreover, our results showed that the CS-PAMAM could significantly improve the cytotoxicity of free methotrexate on A549 cells. These results demonstrate that CS-PAMAM may provide a suitable platform for the water-insoluble drug delivery.

[An experimental study on homologous vascularized nerve transplantation after ultra deep cryopreservation].

OBJECTIVE: To study the feasibility of homologous vascularized nerve transplantation after ultra deep cryopreservation. METHODS: Vascularized sciatic nerve from 12 female dogs was transplanted after ultra deep cryopreservation. Forty-eight male dogs were divided into 4 groups: ultra deep cryopreservation homologous vascularized nerve (group A), ultra deep cryopreservation homologous nerve (group B), fresh homologous vascularized nerve (group C), and fresh autologous vascularized nerve (group D). The gross appearance, patency rate of artery and morphological transplanted nerve were observed 1, 4 and 12 weeks after transplantation respectively. Immunological analysis was performed using IL-2 assay and T lymphocyte subpopulations assay after 4 weeks. Image pattern analysis and electromyogram were observed after 12 weeks. RESULTS: In groups A and D, no toe ulcer occurred, the atrophy of later limb and the sense of pain from skin of calf were restore significantly in the postoperative 12th week. In groups B and C, toe ulcer occurred, the atrophy of later limb and the sense of pain from skin of calf were not restored significantly in the postoperative 12th week. The vessel patency rate of groups A and D was 83.3%, which was significantly higher than that of group C (50%, P < 0.05). The changes of IL-2 and Th, Ts in group C were significantly higher than that in groups A, B, D (P < 0.01). There were increased vessel and regenerated nerve in transplanted nerve under optical microscope and image pattern analysis in groups A and D. There were shorter latent period of motor evoked potential, greater amplitude of action potential and faster motor nerve conducting velocity in groups A and D after 12 weeks. CONCLUSION: The antigenicity of the homologous never and vessel may be reduced significantly by being frozen, and cryopreserved vascularized nerve can transferred successfully without the use of immunosuppressive agents. Vascularized nerve may restore good significantly for the thick nerve.