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Bearing sleeve, as one of important parts of bearing structure, determine the bearing performance directly. In this paper, based on the ball joint structure, the tribological properties between Polyoxymethylene (POM) and 40Cr are studied with Ring-Block method. The effects of friction velocity and applied load on friction coefficient are tested and analysed, the analytical model in friction force, friction velocity and applied load are created, which will provide useful technical data to the application.

Though common, the extraction of rectal foreign bodies is still a great challenge for surgeons. The foreign body's position can usually be verified by plain abdominal radiography. Given the potential of sexually transmitted disease, screening for HIV, hepatitis, and syphilis is warranted prior to intervention. The utilization and selection of surgical instruments need to be flexible, ingenious, and innovative.

An oncologic defect that includes both the lower eyelid and the infraorbital cheek often results in complex reconstructive problems because its reconstruction involves 2 distinct tissue types and cosmetic subunits. Herein, we first present a novel combination of modified supratrochlear artery forehead island flap and advancement rotation cheek flap enables reconstructing a large oncologic defect of lower eyelid and infraorbital cheek. Although discoid lupus erythematosus affects the skin, the patient had achieved a satisfying color match and an acceptable aesthetic restoration without tumor recurrence. This novel flap has shown to be feasible, reliable, and advantageous alternative to the repair of such defects.

Aluminum ball joint is an advanced structure using to connect steering parts with the merits of simple and lighting. Usually extrusion strength and torque are the most important parameters to evaluate the ball joint properties. Generally, the ball sealed in the Aluminum housing by forming method which has an impact on the extrusion strength and torques. So how to control the forming and achieve the best properties is very important. In the paper, the relations between housing dimension and strength, torque are studied; the influence of forming on torque is researched. The rules in them are achieved.

Based on the selenium ion beam assisted magnetron sequential sputtering technology, low temperature deposition of CIS thin-film solar cells in high quality can be achieved. By comparing with the method of conventional gas phase atomic deposition, and through simulated analysis from the perspective of diffusion uniformity, numerical calculation on the depth of ion beam injection is proceeded. First, according to the classical collision theory in molecular dynamics, the theoretical calculation on the process of ion implantation is done; the concentration distribution of implanted selenium ions can be got by using TRIM program for simulation analysis. On this basis, the concentration distribution of selenium ion after diffusion can be further obtained. Finally, the calculation model is established; through comparison and analysis, when the selenium diffusion uniformity is same in the both conditions, the substrate temperature T1 needed for ion beam assisted deposition and the substrate temperature T2 needed for gas phase atomic deposition are respectively calculated. The calculation results show that on the premise of merely considering the depth of implanted ions, from the perspective of the diffusion uniformity, the selenium ion beam assisted deposition technique can obviously reduce the substrate temperature comparing with traditional vapor deposition technology.

CIGS thin film solar cells on polyimide substrate was a significant developmental direction of solar cells and fabricating high quality CIGS thin film in low temperature was its pivotal technology. The development of manufacturing the CIGS thin film solar cells on polyimide substrate in low temperature was described. The specific principle, manufacturing technique and application prospect were also involved. The problem should be solved in the future progress of CIGS thin film on polyimide substrate was illustrated.

In order to eliminate cracks in the chromium coating, a novel method named flexible extrusion assisted chromium electroplating was proposed. The bright and crack-free chromium coatings were electrodeposited by using the perturbation and extrusion of hard and insulating particles. The prepared deposits were characterized by scanning electron microscope (SEM) and three-dimensional topography. The testing results showed that the surface was very smooth and there was no micro cracks in the coating. Micro hardness of the electrodeposited layer was also tested. It was confirmed that the chromium coating electrodeposited with rotating cathode in hard particles had high micro hardness as to 850HV and the micro hardness could be controlled by the process parameters. The rule of the micro hardness was concluded by analyzing current density and rotating speed. In addition the results of salt spray test and electrochemical polarization curve showed that the coating deposited by new method had higher corrosion resistance than that by traditional method.

In this paper, we analyze and point out several weaknesses in the dynamic ID-based remote user authentication schemes using smart card for multi-server environments, and present the countermeasures to enhance the security of the schemes. Taking Li et al.'s scheme for instance, we demonstrate that their scheme does not provide forward secrecy and key privacy for the session keys, and cannot resist offline password guessing attack. Furthermore, the reasons of these security weaknesses are analyzed through extending the attacks to its predecessors. Finally, the improved ideas of local verification and authenticated Diffie-Hellman key agreement are presented to overcome the weaknesses mentioned above.

In order to obtain the sheet metal anisotropy under wide strain range, plane strain compression method with laminated samples is investigated. In the experiments, two laminated samples are introduced, sample 1 is deformed at rolling and thickness direction, and sample 2 is deformed at rolling and transverse direction. In the paper, the ratio of deformation forces obtained from sample 2 (p2 ) to sample1( p1) is used to assess the anisotropy of sheet metal, and verified by analytical method. The results show that the ratio of p2top1 is the function of anisotropic index r, and the anisotropic assessment by this method has a good agreement with that obtained by universal uniaxial tensile test at uniform deformation.

Aluminum ball joint is an advanced structure using to connect steering parts with the merits of simple and lighting. Usually the ball sealed in the Aluminum housing through riveting forming method which has an impact on the push out strength and ball joint torques directly. So how to control the riveting process and achieve the best properties match is very important. In the paper, the relations in the riveting processes, push out strength and torque are studied using experimental method. The parameters affected the push out strength and torque are studied and the influence rules are achieved. The analytical model to present the push out strength is established.

Autophagy (macroautophagy) is a degradative process that involves the sequestration of cytosolic material including organelles into double membrane vesicles termed autophagosomes for delivery to the lysosome. Autophagy is essential for preimplantation development of mouse embryos and cavitation of embryoid bodies. The precise roles of autophagy during early human embryonic development, remain however largely uncharacterized. Since human embryonic stem cells constitute a unique model system to study early human embryogenesis we investigated the occurrence of autophagy in human embryonic stem cells. We have, using lentiviral transduction, established multiple human embryonic stem cell lines that stably express GFP-LC3, a fluorescent marker for the autophagosome. Each cell line displays both a normal karyotype and pluripotency as indicated by the presence of cell types representative of the three germlayers in derived teratomas. GFP expression and labelling of autophagosomes is retained after differentiation. Baseline levels of autophagy detected in cultured undifferentiated hESC were increased or decreased in the presence of rapamycin and wortmannin, respectively. Interestingly, autophagy was upregulated in hESCs induced to undergo differentiation by treatment with type I TGF-beta receptor inhibitor SB431542 or removal of MEF secreted maintenance factors. In conclusion we have established hESCs capable of reporting macroautophagy and identify a novel link between autophagy and early differentiation events in hESC.

Objective: To compare the positions of the mandibular premolars in Angle Class I subjects according to vertical facial type. The results will provide a theoretical basis for predicting effective tooth movement in orthodontic treatment. Methods: Cephalometric parameters were determined using cone-beam computed tomography in 120 Angle Class I subjects. Subjects were categorized as short, normal, and long face types according to the Frankfort mandibular angle. Parameters indicating the position of the mandibular right premolars and the mandible were also measured. Results: The angle between the mandibular first premolar axis and buccal cortex, the distance between the root apex and buccal cortex, angle of vestibularization, arc of vestibularization, and root apex maximum movable distance were significantly greater in the short face type than in the long and norm face types. The angle between the mandibular second premolar axis and buccal cortex, the distance from root apex to buccal cortex, and the arc of vestibularization were significantly greater in the short face type than in the normal face type. Conclusions: There are significant differences in the mandibular premolar positions in Class I subjects according to vertical facial type. [Korean J Orthod 2015;45(4):180-189]

To determine the optimal position of hypoglossal nerve in hypoglossal-facial nerve anastomosis and the eligibility of hypoglossal-facial nerve anastomosis with the cervical loop.The cervical course and adjacent structures of the hypoglossal nerve were observed on 21 adult cadavers. The hypoglossal nerve and facial nerve were taken from 3 fresh specimens, and the number of the fasciculus and the cross-sectional area of the nerve were measured.The facial nerve trunk were monofascicular with a cross-sectional area of 5.1-/+0.2 (range 4.6-5.7) mm(2). The number of the fasciculus and the cross-sectional areas of the nerve trunk and the fasciculus were 1.6-/+0.8 (range 1-4) mm(2) , 7.5-/+0.7 mm(2) (range 6.8-8.0) mm(2), and 4.7-/+0.6 (4.1-5.5) mm(2), respectively, at the proximal segment of the hypoglossal nerve, 3.6-/+0.5 (1-5) mm(2) , 5.6-/+0.5 (4.9-6.1) mm(2) , and 1.6-/+0.4 (0.9-2.2) mm(2) at the distal segment, and 2.4-/+0.8 (1-3) mm(2), 1.1-/+0.7 (0.6-2.2) mm(2), and 0.5-/+0.3 (0.3-1.2) mm(2) at the cervical loop.The cervical loop is inadequate for facial nerve anastomosis and the proximal segment is large enough to allow partial harvesting of the hypoglossal nerve for neurotisation of the facial nerve.

This work analyses the rule of the base vector arrangement for slant transform, gives the equations and the fast algorithms for the slant transform of arbitrary order 2" with base vectors arranged in sequency increment, makes traditional slant transform theory more consummate. Using this algorithm in image compression, the data entropy in the transform domain approaches that of the commonly used DCT, but the operation speed is faster. This algorithm is suitable for the orthogonal transformation where high speed and hardware implementation are required.

To evaluate the postoperative long-term hearing results of small fenestra stapedectomy versus large fenestra techniques.A retrospective review of 102 ears of 94 patients who had stapedectomy (small fenestra technique) performed by the same surgeon between 1972-1990 was conducted. Patients undergoing stapedectomy and stapedotomy were followed for 6.4 +/- 2.2 and 6.6 +/- 3.0 month in initial postoperative and 14.5 +/- 3.0 and 7.4 +/- 2.2 years in late postoperative, respectively.There were no statistically significant differences in initial or late postoperative pure-tone (PTA), PTA air-bone gap, speech reception threshold (SRT) between the two groups. Ears treated by stapedotomy showed statistically better initial postoperative air-conduction threshold and initial 4-KHz air-bone gap closure, but the gap difference was not significant with late follow-up. The successful outcomes in both groups were stable over long-term follow-up. Results were the same when comparing the two procedures in the patients having undergone both.These results show that, in the operation of an experienced surgeon for otosclerosis, either large or small fenestra technique provides satisfactory and stable long-term results.