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This study aims to evaluate the performance of various fully convolutional network (FCN) models in segmenting splenic hemorrhage in 2D CT images, focusing on emerging techniques and approaches for improved segmentation. A total of 692 2D CT images of splenic hemorrhage was collected from a hospital (IRB: EMRP-109-037). Five FCN models, including inceptionresnetv2, mobilenetv2, resnet18, resnet50, and xception, were used for splenic hemorrhage segmentation. The hyperparameters included batch size, epoch size, and learning rates (0.001). The dataset was divided into 70%, 20%, and 10% for training, validation, and testing of the FCN models, respectively. The mean accuracy and mean intersection over union (IoU) were utilized to assess the performance of each FCN model. The optimal mean accuracy achieved by the inceptionresnetv2, mobilenetv2, resnet18, resnet50, and xception models were 0.804, 0.820, 0.788, 0.747, and 0.663, respectively. Moreover, the mean IoU provided by the five FCN models were 0.697, 0.705, 0.705, 0.691, and 0.631. This study demonstrates the potential of various FCN models in segmenting splenic hemorrhage in CT images, with mobilenetv2 and resnet18 models showing the most promising performance. The RESULTS: may contribute to future advancements in CT splenic hemorrhage segmentation and clinical applications. Employing mean accuracy and mean IoU as performance metrics offers an Objective: and comprehensive assessment of segmentation quality. [ABSTRACT FROM AUTHOR]

Abstract Objectives This study aimed to develop a simple and efficient numerical modeling approach for characterizing strain and total strain energy in bone scaffolds implanted in patient-specific anatomical sites. Materials and methods A simplified homogenization technique was developed to substitute a detailed scaffold model with the same size and equivalent orthotropic material properties. The effectiveness of the proposed modeling approach was compared with two other common homogenization methods based on periodic boundary conditions and the Hills-energy theorem. Moreover, experimental digital image correlation (DIC) measurements of full-field surface strain were conducted to validate the numerical results. Results The newly proposed simplified homogenization approach allowed for fairly accurate prediction of strain and total strain energy in tissue scaffolds implanted in a large femur mid-shaft bone defect subjected to a simulated in-vivo loading condition. The maximum discrepancy between the total strain energy obtained from the simplified homogenization approach and the one obtained from detailed porous scaffolds was 8.8%. Moreover, the proposed modeling technique could significantly reduce the computational cost (by about 300 times) required for simulating an in-vivo bone scaffolding scenario as the required degrees of freedom (DoF) was reduced from about 26 million for a detailed porous scaffold to only 90,000 for the homogenized solid counterpart in the analysis. Conclusions The simplified homogenization approach has been validated by correlation with the experimental DIC measurements. It is fairly efficient and comparable with some other common homogenization techniques in terms of accuracy. The proposed method is implicating to different clinical applications, such as the optimal selection of patient-specific fixation plates and screw system. Graphical abstract fx1 Highlights • The proposed simplified homogenization approach could predict the total strain energy accurately. • Computational cost was decreased substantially  by using the proposed homogenization approach. • Validation of homogenization results with digital image correlation (DIC) measurements for bone tissue scaffolding. • Numerical results were in good agreement with those of the experimental results. [ABSTRACT FROM AUTHOR]

Under the time-based criteria, patients with unknown onset stroke (UOS) are ineligible for reperfusion therapies. However, previous studies suggest that some patients with UOS may benefit from reperfusion. Several imaging modalities have been suggested to select patients for intervention, but the optimal imaging criteria are still controversial. Herein we present a series of four cases using 10-point CT-ASPECTS to support our decision of reperfusion therapy. We decided based on history, symptoms, and the 10-point CT-ASPECTS alone. Each patient's history suggested that the stroke just took place. All four patients had apparent clinical symptoms, with 10-point CT-ASPECTS. All of them had a reduction in their NIHSS after the reperfusion therapy. 10-point CT-ASPECTS could be used to support the presumption that the stroke just happens in patients with UOS. Further study is warranted to elucidate the value of CT-ASPECTS for UOS patients. [ABSTRACT FROM AUTHOR]

Background/Purpose In a recent study, we found that baicalin exhibited a potent analgesic effect on carrageenan-evoked thermal hyperalgesia. The underlining mechanisms may be associated with inhibition of inflammatory mediator overproduction, including proinflammatory cytokines, nitric oxide (NO), and prostaglandin E2 (PGE2). In the present study, we examined the effect of baicalin on the antinociceptive effect of morphine and histone deacetylase 1 (HDAC1) expression in the spinal cord dorsal horn in neuropathic pain rats. Methods Neuropathic pain was induced by tight ligation of the left L5 spinal nerve of the rats. An intrathecal catheter was implanted for drug administration. Nociception was assessed by using the plantar test with the Hargreaves radiant heat apparatus, and the von Frey test with the dynamic plantar anesthesiometer. Spinal cords were removed for histone acetyl-H3 and HDAC1 western blot analysis at the end of the nociceptive assessment. Results The results showed that hyperalgesia and allodynia were observed in the spinal nerve ligated (SNL) left hindlimb; it was companied by histone-H3 deacetylation and HDAC1 overexpression on the ipsilateral side of the spinal cord dorsal horn. Intrathecal injection of baicalin (10 μg) significantly attenuated the allodynia and hyperalgesia, and enhanced the antinociceptive effect of morphine (15 μg). Moreover, baicalin reversed the histone-H3 acetylation and suppressed HDAC1 expression on the ipsilateral side of the spinal cord dorsal horn of SNL rats. Conclusion The present findings suggest that baicalin can ameliorate neuropathic pain by suppressing HDAC1 expression and preventing histone-H3 acetylation in the spinal cord dorsal horn of SNL rats. [ABSTRACT FROM AUTHOR]

Abstract: Cuttlebone is a natural marine cellular material possessing the exceptional mechanical properties of high compressive strength, high porosity and high permeability. This combination of properties is exceedingly desirable in biomedical applications, such as bone tissue scaffolds. In light of recent studies, which converted raw cuttlebone into hydroxyapatite tissue scaffolds, the impact of morphological variations in the microstructure of this natural cellular material on the effective mechanical properties is explored in this paper. Two extensions of the finite element-based homogenization method are employed to account for deviations from the assumption of periodicity. Firstly, a representative volume element (RVE) of cuttlebone is systematically varied to reflect the large range of microstructural configurations possibly among different cuttlefish species. The homogenization results reveal the critical importance of pillar formation and aspect ratio (height/width of RVE) on the effective bulk and shear moduli of cuttlebone. Secondly, multi-cell analysis domains (or multiple RVE domains) permit the introduction of random variations across neighboring cells. Such random variations decrease the bulk modulus whilst displaying minimal impact on the shear modulus. Increasing the average size of random variations increases the effect on bulk modulus. Also, the results converge rapidly as the size of the analysis domain is increased, meaning that a relatively small multi-cell domain can provide a reasonable approximation of the effective properties for a given set of random variation parameters. These results have important implications for the proposed use of raw cuttlebone as an engineering material. They also highlight some potential for biomimetic design capabilities for materials inspired by the cuttlebone microstructure, which may be applicable in biomedical applications such as bone tissue scaffolds. [Copyright &y& Elsevier]

This study considered the stability of nickel oxide nanoparticles (nNiO) in seawater including their ability of aggregation and ion release. Furthermore, the relationship between these properties and their toxicity on marine algae Chlorella vulgaris was investigated. The results showed nNiO inhibited the growth of algal cells and decreased their chlorophyll content, which was due to the shading effects by aggregation of nNiO in seawater. Moreover, the release of Ni2+ depended on concentration of the nNiO solution. About 1.63% Ni2+ (varied from 0.89 to 3.63%) was detected and it may mediate the generation of ROS under both visible light and ultraviolet (UV) irradiation, which resulted in oxidative stress in algae. Therefore, the stability of nNiO in water affected its toxicity, which should be considered when assessing the nano-pollution risks in aquatic ecosystem. Unlabelled Image • nNiO caused adverse effects to marine algae. • Possibility of aggregation of nNiO was more in seawater than in fresh water. • Ni ions mediated the redox process of nNiO to Ni as well as the generation of ROS. • Shading effect and oxidative stress caused biotoxicity of nNiO on microalgae. [ABSTRACT FROM AUTHOR]

As the level of CO 2 within the vehicle cabin increases, the risk of accidents as a result of driver drowsiness and a slowing of the reactions also increases. Accordingly, a CFD simulation model was developed in this study to explore the effects of outdoor air ventilation rate on vehicle cabin indoor air quality and the amount of outdoor air required for each person in a vehicle. The results show that using the outdoor air supply rate recommendations of ASHRAE Standard 62.1 (i.e. 2.5 l/s per person) the mean CO 2 concentrations in the cabin are around 2850 ppm. The results also show that using the outdoor air supply rate recommendations of 4.0 l/s per person for improved human wellbeing, the corresponding mean CO 2 concentrations in the cabin are around 1810 ppm. Moreover, the present study found that an outdoor fresh air flow rate of 9.2 l/s per passenger was sufficient to reduce the carbon dioxide concentration within the cabin to a safe value of 1000 ppm. Furthermore, an outdoor fresh air flow rate of 3.6 l/s per passenger resulted in a carbon dioxide concentration of around 2000 ppm. [ABSTRACT FROM AUTHOR]

Human Mps1 (hMps1) is a mitotic checkpoint kinase responsible for sensing the unattached and tensionless kinetochore. Despite its importance in safeguarding proper chromosome segregation, how hMps1 is recruited to the kinetochore remains incompletely understood. Here, we demonstrate that phosphorylation at Thr-288 by the cell cycle checkpoint kinase CHK2 is involved in this process. We discovered that the phosphorylation-deficient T288A mutant has an impaired ability to localize to the kinetochore and cannot reestablish the mitotic checkpoint in hMps1-depleted cells. In support, we found that nocodazole induced hMps1 phosphorylation at the previously identified CHK2 site Thr-288 and that this could be detected at the kinetochore in a CHK2-dependent manner. Mechanistically, phosphorylation at Thr-288 promoted the interaction with the KMN (KNL1-Mis12-Ndc80 network) protein HEC1. Forced kinetochore localization corrected the defects associated with the T288A mutant. Our results provide evidence of a newly identified hMps1 phosphorylation site that is involved in the mitotic checkpoint and that CHK2 contributes to chromosomal stability through hMps1. [ABSTRACT FROM AUTHOR]

In a Ag–8Au–3Pd wire, a large number of annealing twins can be observed. In contrast to the rapid grain growth in Au and Cu wires during aging at 600°C, the grain size of this Ag alloy wire remained almost unchanged. The annealing twins in this material also possess the dual merits of increasing strength and elongation with aging time, while the electrical resistivity remained constant. [Copyright &y& Elsevier]