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The study investigated the effects of long-term glucocorticoid (GC) administration on bone remodelling, microstructure, and biomechanical strength in cortical and cancellous (trabecular) bones. Thirty-one female Sprague-Dawley rats were randomly divided into three dexamethasone (Dex) dosage groups, 1.0, 2.5, and 5.0 mg/kg twice a week for 8 weeks, and one control group treated with saline. At the end of the experiment, the tibia of one side and the fourth lumbar vertebrae were processed into sections for a histomorphometric analysis, while the femur of the same side and the fifth vertebrae were isolated for a biomechanical test. A dose-dependent decline in bone formation was observed in both trabecular and cortical (periosteal and endosteal) bones. In contrast, bone resorption was inhibited only in cancellous bone in the two higher dose groups and not dose-related. The ratio of Node/Termini increased, while marrow star volume (MSV) decreased in all Dex groups in metaphyseal trabecular bones, both of which were dose-dependent. Subendosteal cortex porosity increased in parallel with non-uniform trabecular distribution, but cortical thickness remained unchanged. Interestingly, there were no significant changes in microstructure or mechanical strength in lumbar trabecular bone. The cortical elastic load was dose-independently reduced in all three Dex groups when compared with the control group. In summary, bone remodelling was dose-dependently inhibited in cancellous bones but enhanced in intracortical bones. The non-uniform distribution of trabecular bone and increased porosity in the inner edge of cortical bone were both in parallel with GC dosage, and the porosity increase was more likely to occur, leading to reduced cortical mechanical strength.

Inspired by the recurrent highway networks, we study the coupled networks as a modular behavior of the networks, which can better improve the performance of the system. For a neural network, the non-zero continuous attractors play an important role to decode the information. The emphasis of this paper is to study the conditions for the generation of non-zero continuous attractors in the coupled new system theoretically. By exploring the relationship between network parameters, the conditions for generating non-zero continuous attractors in the new model are successfully determined. In order to verify the correctness and validity of the proposed conclusions, the results of this paper are further verified by simulation.

A continuous attractor of recurrent neural network is a connected set of stable equilibrium points. It's widely used to interpret a lot of brain activities. A large number of literatures have studi...

The planetary boundary layer (PBL) or atmospheric boundary layer (ABL) refers to the part of the atmosphere that is directly influenced by the Earth’s surface and responds to surface forces. In this paper, the temperature gradient method that uses the Atmospheric Infrared Sounder (AIRS) atmospheric potential temperature profile product to derive the planetary boundary layer height (PBLH) is introduced and applied over the Heihe River Basin (HRB). The method is applicable during clear and cloudy days for both convective and stable air conditions. The reanalysis PBLH from the Modern Era Retrospective analysis for Research and Applications (MERRA) data and the in situ PBLH calculated from HIWATER (Heihe Watershed Allied Telemetry Experimental Research) radiosonde data were both prepared for validation. The comparison shows that the spatial variation in the PBLH from the AIRS is consistent with the MERRA PBLH at the annual scale, and the PBLH from our method has an average of 313 m RMSE and 0.84 R2 with the station in situ PBLH calculated from sounding data. The study demonstrates that remote sensing methodologies can successfully estimate the MH under different atmosphere condition without the need for ancillary field measurements.

Glucocorticoids (GCs) are often prescribed to treat rheumatoid arthritis (RA) in the long term, but there is still controversy in the administration of GCs, mainly because of the adverse reactions such as osteoporosis. Numerous studies have demonstrated that osteoporosis could be induced by GCs in normal rats. However, few experiments have focused on whether osteoporosis could be induced or aggravated by GCs in collagen induced arthritis (CIA) rats. We have investigated bone changes in CIA rats treated with prednisone at 4.5 mg/kg/day for 30 and 90 days by bone histomorphometry, bone mineral density (BMD), micro-CT, biomechanical test, and enzyme-linked immunosorbant assay. We found that high bone turnover osteoporosis was shown in CIA rats. Prednisone treatment for 30 and 90 days improved articular structure and decelerated the degeneration of the femur in CIA rats, but did not improve BMD and bone biomechanics. We conclude that osteoporosis was not aggravated in CIA rats treated with prednisone for 30 and 90 days. On the contrary, prednisone treatment for 30 and 90 days could prevent bone loss of the femur in CIA rats. There was a negative effect on bone metabolism in CIA rats treated with prednisone for 90 days.

Aim To investigate the bone-protective effects of salvianolate (Sal), a total polyphenol from Radix Salviae miltiorrhizae, on bone tissue in the spontaneous lupus-prone mouse model, B6.MRL-Fas (lpr) /J, undergoing glucocorticoid (GC) treatment. Methods Fifteen-week-old female B6.MRL-Fas (lpr) /J mice were administered either a daily dose of saline (lupus group), prednisone 6 mg/kg (GC group), Sal 60 mg/kg (Sal group); or GC plus Sal (GC + Sal group) for a duration of 12 weeks. Age-matched female C57BL/6J wild-type (WT) mice were used for control. Micro-computed tomography assessments, bone histomorphometry analysis, bone biomechanical test, immunohistochemistry and immunoblotting analysis for bone markers, and renal histology analysis were performed to support our research endeavor. Results Lupus mice developed a marked bone loss and deterioration of mechanical properties of bone due to an increase in bone resorption rather than suppression of bone formation. GC treatment strongly inhibited bone formation in lupus mice. Sal treatment significantly attenuated osteogenic inhibition, and also suppressed hyperactive bone resorption, which recovered the bone mass and mechanical properties of bone in both the untreated and GC-treated lupus mice. Conclusion The data support further preclinical investigation of Sal as a potential therapeutic strategy for the treatment of systemic lupus erythematosus-related bone loss.

In this study, we introduce a method for large-area and substrate-independent synthesis of the big-inner-diameter carbon nanotube (BIDI-CNT) thin films by utilizing polydopamine (PDA) as carbon source and ZnO nanorods (NRs) as sacrificing template for the first time. ZnO NRs with hexagonal morphology were coated with PDA films via the ammonium persulfate-induced polymerization of dopamine at neutral pH for avoiding the degradation of amphoteric ZnO at alkaline pH needed by the conventional oxygen-induced polymerization of dopamine. After carbonization in N 2 atmosphere at 500 °C followed by ZnO removal, the hollow BIDI-CNTs with tuned wall thickness and hexagonal morphology were obtained. In addition, the obtained BIDI-CNTs were found to be N-doped. Furthermore, on the base of the outstanding substrate-independent growth properties of both ZnO NRs and PDA, the large area thin films of the N-doped BIDI-CNTs could be synthesized on various solid substrates, for instance, Al 2 O 3 , gold, fluorine-doped tin oxide-coated glass, platinum, silicon, mica, and quartz.

Summary In this paper we discuss a case study of inversion using wide-azimuth data for fracture-cavity characterization of the d eep carbonate reservoirs in Tahe Oilfield. The method is based on Chapman's Theory (2003), assuming that the rock is dispersive, also has the dispersion and azimuthal anisotropy properties. In short, dispersion properties are changing with the azimuth. The result of frequencydependent AVO inversion shows a good correlation with the post-stack coherence properties, and the ellipse-fitted result of dispersion properties also shows a good correlation with the well data. This method has been proved effectively and meaningfully in the carbonate fracturecavity reservoir prediction.

Numerous studies have demonstrated that rheumatoid arthritis (RA) is often associated with bone loss; however, few experiments have focused on cancellous and cortical bone changes in rats during the process of arthritis. We have investigated bone changes in rats with collagen-induced arthritis (CIA) and have explored the characteristics of how RA induces osteoporosis by means of bone histomorphometry, bone biomechanics studies, bone mineral density studies, micro computer tomography, enzyme-linked immunosorbant assay, immunohistochemistry, and Western blot analysis. Bone mineral density of the femur and lumbar vertebrae and biomechanical properties of the femur were decreased in CIA rats. Trabecular bone volume of the tibia and lumbar vertebrae was decreased whereas bone resorption was increased in CIA rats. Bone formation of the tibial shaft in periosteal surfaces was decreased in CIA rats. Furthermore, the trabecular bone loss in CIA rats was severer at 16 weeks than at 8 weeks, as was cortical bone loss. The serum level of tumor necrosis factor α in CIA rats was increased, and the expression of dickkopf 1 and that of receptor activator of nuclear factor κB (RANKL) ligand (RANKL) in the ankle joints were also increased, but the expression of osteoprotegerin (OPG) was decreased. We conclude that CIA rats developed systemic osteoporosis, and that osteoporosis became more serious with CIA development. The mechanism may be related to the increase of bone resorption in cancellous bone cause by upregulation of the expression of DKK-1 and regulation of the RANKL/RANK/OPG signaling pathway, and the decrease of bone formation in cortical bone caused by an increase in the expression of DKK-1.