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To explore the incidence and risk factors of readmission of elderly patients with hip fracture after hip hemiarthroplasty.A retrospective analysis of 237 elderly hip fracture patients who underwent hip hemiarthroplasty from February 2015 to October 2020 were performed. According to the readmission status of the patients at 3 months postoperatively, the patients were divided into readmission group (39 cases)and non-readmission group(198 cases). In readmission group, there were 7 males and 32 females with an average age of(84.59±4.34) years old, respectively, there were 34 males and 164 females with average age of (84.65±4.17) years old in non-readmission group. The general information, surgical status, hip Harris score and complications of patients in two groups were included in univariate analysis, and multivariate Logistic regression was used to analyze independent risk factors of patients' readmission.The proportion of complications(cerebral infarction and coronary heart disease) in readmission group was significantly higher than that of non-readmission group (The complications of the elderly patients who were readmission after hip hemiarthroplasty for hip fractures were significantly higher than those who were non-readmission. Cerebral infarction, infection, delirium, dislocation, anemia and venous thrombosis are risk factors that lead to patient readmission. Corresponding intervention measures can be taken clinically based on these risk factors to reduce the incidence of patient readmissions.

The essential role of GAPDH/Siah1 signaling pathway in the pathogenesis of various injurious conditions such as traumatic spinal cord injury (SCI) has been gradually recognized. However, the drugs targeting this signaling pathway are still lacking. The endocannabinoid system, including its receptors (CB1 and CB2), act as neuroprotective and immunomodulatory modulators in SCI. WIN55212-2, an agonist for CB1 and CB2 receptors, has been demonstrated with anti-inflammatory and anti-apoptotic effects in multiple neurological diseases. Therefore, the present study aimed to investigate whether WIN55212-2 could promote functional recovery after traumatic SCI via inhibition of the GAPDH/Siah1 signaling. The traumatic SCI was induced by dropping a 10-g impactor from 25mm on the dorsal surface of T9 and T10. Our results showed that WIN55212-2 alleviated the activation of GAPDH/Siah1 signaling pathway after SCI, as indicated by the reduction in GAPDH nuclear expression, GAPDH-Siah1 complex formation and iNOS protein expression. Furthermore, WIN55212-2 reduced apoptosis, production of IL-1β and TNF-α and activation of NF-κB signaling in the spinal cord after SCI. The behavioral tests showed that WIN55212-2 improved the functional recovery after traumatic SCI as indicated by sustained increase in the locomotor scores. However, these neuroprotective effects of WIN55212-2 were blocked in the presence of the combined treatment of AM630 (an antagonist of CB2) rather than AM251 (an antagonist of CB1). In conclusion, our study indicates that, WIN55212-2 improves the functional recovery after SCI via inhibition of GAPDH/Siah1 cascades in a CB2 receptor dependent manner, indicative of its therapeutic potential for traumatic SCI or other traumatic conditions.

To reveal the static stiffness behavior of a 6-PTRT parallel robot and find out its change rule in order to provide the reasonable parameters for the structural design, the stiffness characteristics of this parallel mechanism was studied. Based on the influence coefficient method, a static stiffness model for 6-PTRT parallel robot was established. The proposed model considered not only the axis stiffness of actuator but also the stiffness of passive joints, and the change of Jacobian matrix and first-order influence coefficient brought about by tiny change of the parallel robot mechanism's configuration under external wrench. The static stiffness matrix of parallel robot in initial position and its stiffness distribution rules for a certain workspace were given by numerical calculation and finite element method, which comparatively verify the exactness of stiffness model.

In order to research laser weapon soft damage to infrared missile, 10.6μm laser disturbance to infrared detector system was researched. First, 10.6μm laser atmospheric propagation transmittance was deduced. Laser atmospheric propagation transmittance relation curve was obtained. The relation curve is changed by atmospheric visibility and laser propagation distance. Then the experiment about on-axis laser disturbance to charge coupled device imaging detectors system was conducted. Charge coupled device saturation power density was measured. The relation curve between charge coupled device saturation area ratio and laser incident energy was obtained. Finally, 10.6μm laser energy which can disturb effectively infrared detector system was calculated. Some valuable data and conclusions were gained.

In order to confirm laser jamming effect on CCD detectors, experiment study on laser jamming CCD detectors was accomplished on axis and off axis. Pixel saturation threshold and saturation power density threshold were measured. Jamming image on axis was processed with computer. The relation curve was described between laser incident energy and CCD saturation area ratio. Jamming image off axis was also processed with computer. The relation curve was described between laser incident angle and CCD saturation area ratio. The experiment result shows that laser jamming CCD imaging guidance weapons is feasible.

Aiming at laser weapon damage to anti-ship missile, laser damage to IR guidance anti-ship missile detectors was researched. First, model on laser weapon damage to IR guidance anti-ship missile detectors was set up. Then 1.06μm and 10.6μm laser atmospheric transmittance on the sea was calculated. Finally, 10.6μm laser was given as an example, the necessary laser energy which can damage effectively the IR guidance anti-ship missile detectors was calculated. Some valuable data and conclusions were gained. It is concluded that laser weapon damage to IR guidance anti-ship missile is feasible at present.

Micro-EDM technology has the advantages of no-contact and no-cutting force, it has been used in many fields. In order to use micro-EDM to machine proprietary micro array holes, which needs high precise of hole spacing and consistent hole diameter, a new macro-micro dual-drive system of micro-EDM have been made. It uses macro drive to move to a place, measures the error with the high precise grating, and uses micro drive to compensate the error. Online measurement proved that this method has important value if it will be used in micro-EDM.

Aiming at laser disturbance to IR homing anti-ship missile, laser disturbance to IR detector was researched. First, link model on laser disturbance to anti-ship missile IR detector was set up. Then laser atmospheric transmittance on the sea was deduced. 1.06μm laser atmospheric transmittance on the sea was calculated. The relationship was obtained among atmospheric transmittance and visibility and elevation. And then 10.6μm laser atmospheric transmittance curve was described. The curve is changed by visibility and propagation distance. Finally, 1.06μm laser was given as an example, the necessary laser energy which can disturb effectively anti-ship missile IR detector was calculated.

Calcium phosphate cement (CPC) porous scaffold is widely used as a suitable bone substitute to repair bone defect, but the optimal pore size is unclear yet. The current study aimed to evaluate the effect of different pore sizes on the processing of bone formation in repairing segmental bone defect of rabbits using CPC porous scaffolds. Three kinds of CPC porous scaffolds with 5 mm diameters and 12 mm length were prepared with the same porosity but different pore sizes (Group A: 200-300 µm, Group B: 300-450 µm, Group C: 450-600 µm, respectively). Twelve millimeter segmental bone defects were created in the middle of the radius bone and filled with different kinds of CPC cylindrical scaffolds. After 4, 12, and 24 weeks, alkaline phosphatase (ALP), histological assessment, and mechanical properties evaluation were performed in all three groups. After 4 weeks, ALP activity increased in all groups but was highest in Group A with smallest pore size. The new bone formation within the scaffolds was not obvious in all groups. After 12 weeks, the new bone formation within the scaffolds was obvious in each group and highest in Group A. At 24 weeks, no significant difference in new bone formation was observed among different groups. Besides the osteoconductive effect, Group A with smallest pore size also had the best mechanical properties in vivo at 12 weeks. We demonstrate that pore size has a significant effect on the osteoconductivity and mechanical properties of calcium phosphate cement porous scaffold in vivo. Small pore size favors the bone formation in the early stage and may be more suitable for repairing segmental bone defect in vivo.

To evaluate contrast-enhanced ultrasonography (CEUS) in detecting testicular perfusion in acute testis contusion.We established the model of testis contusion in 11 healthy male New Zealand rabbits by randomly hitting one side of the scrotum under general anesthesia. We examined the bilateral scrotums of all the animals before, immediately after and at 2, 4 and 6 hours after modeling by color Doppler flow imaging (CDFI) and CEUS, and analyzed the time-intensity curve (TIC), arriving time (AT), time to peak intensity (TTP), peak intensity (PI), half time of descending peak intensity (HT) and area under the curve (AUC) in the healthy and injured testis, respectively.CEUS exhibited a higher sensitivity in detecting tissue perfusion than CDFI. The mode of contrast agent perfusion in testicular contusion was fast in and slow out. There were no evident differences between the contused and the healthy testis in AT, TTP and PI before modeling. The contused testis showed significantly earlier AT and TTP, higher PI and larger AUC (P0.05) than the healthy one at different time points after modeling, but no statistically significant difference was found in HT (P0.05).Accurate parameters of testicular perfusion in acute testis contusion can be quantitatively obtained by CEUS, which are of important value for the diagnosis of testis contusion.

In order to reduce infrared image noise, infrared image smoothing is studied for warship targets. A valid algorithm is presented. The algorithm is in favor of real-time image processing. Firstly, neighborhood average was applied to infrared image for warship targets. Then median filter was analyzed. An improved median filter algorithm was presented. It is named pseudo median filter. Pseudo median filter was applied to infrared image. Then simulation experimental results are comprehensively analyzed. Pseudo median filter is valid in infrared image smoothing for warship targets. Finally, some problems about feasibility in realization were analyzed. Hence a conclusion was obtained. Pseudo median filter is considered feasible in infrared image smoothing for warship targets.

Agent based programming has been described as the next significant breakthrough in software development, and it has been used for building intelligent agents. The agent-oriented approach is increasingly being applied in industrial applications, but it is far from as widespread as the object-oriented approach. Also the paper describes where and how agents have been applied to the manufacturing industry successfully. Agent-0 language is a programming paradigm promoting a social view of computing, where “agents” interact. Agent-0 is a language in the AOP paradigm that uses KQML for communication. In this paper, the syntax, framework and interpreter of an Agent-0 program are introduced.

Estrogen deficiency is the main reason of bone loss, leading to postmenopausal osteoporosis, and estrogen replacement therapy (ERT) has been demonstrated to protect bone loss efficiently. Notch signaling controls proliferation and differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Moreover, imperfect estrogen-responsive elements (EREs) were found in the 5′-untranslated region of Notch1 and Jagged1. Thus, we examined the molecular and biological links between estrogen and the Notch signaling in postmenopausal osteoporosis in vitro. hBMSCs were obtained from healthy women and patients with postmenopausal osteoporosis. Notch signaling molecules were quantified using real-time polymerase chain reaction (real-time PCR) and Western Blot. Luciferase reporter constructs with putative EREs were transfected into hBMSCs and analyzed. hBMSCs were transduced with lentiviral vectors containing human Notch1 intracellular domain (NICD1). We also used N-[N-(3, 5-diflurophenylacetate)-l-alanyl]-(S)-phenylglycine t-butyl ester, a γ-secretase inhibitor, to suppress the Notch signaling. We found that estrogen enhanced the Notch signaling in hBMSCs by promoting the expression of Jagged1. hBMSCs cultured with estrogen resulted in the up-regulation of Notch signaling and increased proliferation and differentiation. Enhanced Notch signaling could enhance the proliferation and differentiation of hBMSCs from patients with postmenopausal osteoporosis (OP-hBMSCs). Our results demonstrated that estrogen preserved bone mass partly by activating the Notch signaling. Because long-term ERT has been associated with several side effects, the Notch signaling could be a potential target for treating postmenopausal osteoporosis. Electronic supplementary material The online version of this article (doi:10.1007/s11010-014-2021-7) contains supplementary material, which is available to authorized users.