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Introduction: Long‐term spaceflight composite stress (LSCS) can cause adverse effects on human systems, including the central nervous system, which could trigger anxiety and depression. Aims: This study aimed to identify changes in hippocampus synaptic plasticity under LSCS. Methods: The present study simulated the real long‐term space station environment by conducting a 42‐day experiment that involved simulating microgravity, isolation, noise, circadian rhythm disruptions, and low pressure. The mood and behavior of the rats were assessed by behavior test. Transmission electron microscopy and patch‐clamp were used to detect the changes in synapse morphology and electrophysiology, and finally, the expression of NMDA receptor channel proteins was detected by western blotting. Results: The results showed that significant weight loss, anxiety, and depressive behaviors in rats were observed after being exposed to LSCS environment for 42 days. The synaptic structure was severely damaged, manifested as an obvious decrease in postsynaptic density thickness and synaptic interface curvature (p < 0.05; p < 0.05, respectively). Meanwhile, LTP was significantly impaired (p < 0.0001), and currents in the NMDAR channel were also significantly reduced (p < 0.0001). Further analysis found that LSCS decreased the expression of two key subtype proteins on this channel. Conclusion: These results suggested that LSCS‐induced depressive behaviors by impairing synaptic plasticity in rat hippocampus. [ABSTRACT FROM AUTHOR]

A tetradentate ligand, 1,1,2,2-tetrakis(4-(pyridin-4-yl)phenyl)ethene (TPPE), was adopted to construct a two-dimensional coordination polymer that incorporated valence tautomerism and luminescence, and the synergistic effect arising from energy transfer from TPPE to the semiquinone moieties was experimentally and theoretically uncovered. [ABSTRACT FROM AUTHOR]

We present a new method of segmentation in which images are segmented in partitions with connected components. We give computationally inexpensive algorithms for probability simulation and simulated annealing on the space of partitions with connected components of a general graph. In particular, Hastings algorithms and generalized Metropolis algorithms are defined to avoid heavy computation. To achieve segmentation, we propose a hierarchical approach which at each step minimizes e cost function on the space of partitions with connected components of a graph. The algorithm is applied to segment gray-level, color, and textured images. Index Terms - Connected components, Gibbs distribution, simulated annealing, hierarchical segmentation, unsupervised segmentation, multiscale segmentation.

We define a distance between textures for texture classification from texture features based on windowed Fourier filters. The definition of the distance relies on an interpretation of our texture attributes in terms of spectral density when the texture can be considered as a Gaussian random field. The distance between textures is then defined as a symmetrized Kullback distance which is a simple function of the attributes and does not require any normalization. An experimental analysis using Gabor filters, and in particular a comparison to quadratic distances, shows the efficiency and robustness of the method. Index Terms - Texture attributes and classification, windowed Fourier filters, Gabor filters, Gaussian random fields, spectral density, Kullback distance, distance between textures, segmentation of textured images.

Objective: To determine the sensitivity and specificity of 640-Multislice CT (640-MSCT) in diagnosing the female UD. Materials and methods: We investigated 16 patients with symptomatic UDs preoperatively in our hospital from August 2010 to March 2016. The patients' average age was 38.8 years. All patients were performed 640-MSCT of pelvis; then, 3D and 4D images were reconstructed preoperatively. Results: In 3D and 4D-CT images, out of 16 patients, thirteen patients had one ostium, two had 2 ostia and one had 3 ostia. Out of those thirteen patients, eight patients' ostia were located at 5 o'clock and five patients' at 7 o'clock. Patients with 2 ostia location were at 5 and 6 o'clock and 5 and 7 o'clock, respectively. Patients with 3 ostia location were at 5, 6 and 7 o'clock. The mean distance from the bladder neck to the ostia was 22.5 mm. The shape of UD was out-pouching in 11 patients (68.8%), U-shaped in four patients (25.0%) and circumferential in 1 patient (6.2%). The CT findings were confirmed by surgical findings. Conclusions: 640-MSCT is a useful tool in identifying UD's shape and ostium (including number, location) before operation. Preoperative 640-MSCT should be an adaptable modality for clinically suspected UD patients. Advances in knowledge: Several imaging methods have been used to diagnose female UD. 640-MSCT may be more suitable to diagnose it for its higher sensitivity and specificity in diagnosis of female UD, especially in identifying UD's shape and number and location of ostium. [ABSTRACT FROM AUTHOR]