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To control the meshing performance of hypoid gear drive, current local conjugate theory and local synthesis method establish a relationship between the relative motion and local geometrical properties of the mating surfaces at one reference point. Theoretically, both local conjugate theory and local synthesis method cannot ensure the contact performance on the entire tooth surface resulting in uncontrolled contact pattern and undesirable transmission error. A global synthesis approach consisting of a machine-tool settings calculation model, a tooth contact analysis model, a meshing quality assessment function, and a swarm intelligence algorithm are proposed. The direction, area, and shape of the contact pattern and the amplitude of the intersection of two adjacent transmission error curves are taken as the evaluation indexes. Three curvatures of the design pitch cone of the pinion are taken as the control variables. A global selection space is then established within the reasonable range of the curvatures. An improved multiple population genetic algorithm is employed to find the optimal set of the curvatures to achieve the target values of the evaluation indexes. To avoid the edge contact and corner contact condition, a feasible region is defined on tooth surface and the contact patterns on the gear and pinion surfaces are all confined within the area. The optimized contact patterns obtained by the loaded tooth contact analysis method are similar to those obtained by the proposed approach, thus demonstrating the effectiveness of this methodology. The main novelty of this approach is to translate the derivation of the mathematical relation between the curvatures of the mating surfaces and the contact properties to solving a multi-objective optimization problem of the meshing quality indexes by the intelligence algorithm.

Accurate evaluation of the misalignment sensitivity of hypoid gears is a significant foundation for analysis of its dynamics and for the calculation of machining parameters. A tooth contact analysis (TCA) methodology considering four kinds of misalignments is presented to calculate the contact pattern and transmission error. A sensitivity model of contact pattern to misalignments is established to investigate the effects of different alignment errors on meshing performance. By parameterizing the contact pattern, the influences of offset error, angular error, and the axial error of pinion and gear on the direction, shape, and position features of contact pattern are studied. Coefficients of four evaluation indexes to different misalignments are defined respectively, and the minimum sum of the weighted coefficients is utilized to establish a multi-objective comprehensive sensitivity model. Three curvatures of the pitch cone of the pinion are taken as the control variables, and a global selection space is then built within the reasonable range of those curvatures. An improved multi-population genetic algorithm (MPGA) is used to find the optimal set of curvatures to achieve the minimum synthetic sensitivity. TCA results indicate that the offset error and angular error have the greatest influence on the contact pattern. By adopting this methodology appropriately, the sensitivity of the contact pattern to misalignments can be reduced. The contributions of this paper can be summarized as: (1) an accurate parameterized measurement model of the contact pattern; (2) a comprehensive sensitivity model of the contact pattern to misalignments; (3) an optimization framework consisting of a calculation model of the machining parameters, a TCA model considering misalignments, and a misalignment sensitivity evaluation model.

Background PRKAA1 encodes α-subunit of 5-AMP-activated protein kinase (AMPK), which has been implicated in the pathogenesis of carcinoma of the stomach. Previous works have suggested that polymorphisms in the PRKAA1 may be associated with the risk of non-cardiac gastric cancer (NCGC), but whether PRKAA1 polymorphisms are related to clinical pathologic characteristics of gastric cancer and its clinical outcome is largely unknown. Methods We carried out a case-control study including a total of 481 gastric cancer patients and 490 healthy controls. The genotypes of enrolled polymorphisms were identified with Sequenom MassARRAY platform. Results This study showed that rs10074991 GG genotype (adjusted OR = 1.44, 95%CI:0.99–2.09, p = 0.056) has a borderline significantly increased risk for gastric cancer, which was consistent with the result of additive model (adjusted OR = 1.21, 95%CI:1.01–1.46, p = 0.042). In similar, an increased risk of gastric cancer was also observed for rs13361707 TC genotype (adjusted OR = 1.47, 95%CI: 1.01–2.14, p = 0.043; additive model: adjusted OR = 1.22, 95%CI: 1.02–1.47, p = 0.033). Furthermore, the rs154268 and rs461404 were also found associated with increased gastric cancer risk, which may be influenced by age, tumor type and differentiation, and tumor stage. Haplotype analysis indicated A-G-C-T-C-G haplotype (rs6882903, rs10074991, rs13361707, rs3805490, rs154268 and rs461404) is associated with increased risk of gastric cancer (OR = 1.29, 95%CI: 1.02–1.62, p = 0.035). The univariate analysis for overall survival (OS) revealed that both of rs10074991 and rs13361707 variants are associated with poor OS in patients with NCGC. Conclusion This case-control study provided the evidence thatrs13361707CC, rs10074991GG, rs461404GG, and rs154268CC are associated with increased gastric cancer risk, especially for NCGC, and that patients with rs10074991 G or rs13361707 C allele have a poor OS.

In eukaryotic cells, autophagy is a process associated with programmed cell death. During this process, cytoplasmic proteins and organelles are engulfed by double‐membrane autophagosomes, which then fuse with lysosomes to form autolysosomes. These autolysosomes then degrade their contents to recycle the cellular components. Autophagy has been implicated in a wide variety of physiological and pathological processes that are closely related to tumorigenesis. In recent years, an increasing number of studies have indicated that nonsteroidal anti‐inflammatory drugs, such as celecoxib, meloxicam, sulindac, aspirin, sildenafil, rofecoxib, and sodium salicylate, have diverse effects in cancer that are mediated by the autophagy pathway. These nonsteroidal anti‐inflammatory drugs can modulate tumor autophagy through the PI3K/Akt/mTOR, MAPK/ERK1/2, P53/DRAM, AMPK/mTOR, Bip/GRP78, CHOP/ GADD153, and HGF/MET signaling pathways and inhibit lysosome function, leading to p53‐dependent G1 cell‐cycle arrest. In this review, we summarize the research progress in autophagy induced by nonsteroidal anti‐inflammatory drugs and the molecular mechanisms of autophagy in cancer cells to provide a reference for the potential benefits of nonsteroidal anti‐inflammatory drugs in cancer chemotherapy.

// Min-Bin Chen 1, * , Yuan-Yuan Liu 1, * , Li-Bo Cheng 2, * , Jian-Wei Lu 3 , Ping Zeng 1 , Pei-Hua Lu 4 1 Department of Radiotherapy and Oncology, Kunshan First People’s Hospital Affiliated to Jiangsu University, Kunshan, China 2 Department of Ophthalmology, Wuxi Second Hospital, Nanjing Medical University, Wu'xi, China 3 Department of Oncology, Jiangsu Cancer Hospital Affiliated to Nanjing Medical University, Nanjing, China 4 Department of Radiotherapy and Oncology, Wuxi People’s Hospital Affiliated to Nanjing Medical University, Wuxi, China * These authors contributed equally to this work and co-first authors Correspondence to: Pei-Hua Lu, email: lphty1_1@163.com Keywords: gastric cancer, AMPKα, Ppm1E, mTOR, miR-135b-5p Received: January 25, 2017 Accepted: February 15, 2017 Published: March 11, 2017 ABSTRACT Activation of AMP-activated protein kinase (AMPK) is a valuable anti-cancer strategy. In the current study, we tested expression and potential function of Ca 2+ /calmodulin-dependent protein kinase phosphatase (Ppm1E), an AMPKα phosphatase, in human gastric cancers. Ppm1E expression was elevated in human gastric cancer tissues ( vs. normal tissues), which was correlated with AMPK (p-AMPKα, Thr-172) dephosphorylation and mTOR complex 1 (mTORC1) activation. Ppm1E upregulation, AMPK inhibition and mTORC1 activation were also observed in human gastric cancer cell lines (AGS, HGC-27, and SNU601). Intriguingly, Ppm1E knockdown by shRNA induced AMPK activation, mTORC1 inactivation, and proliferation inhibition in AGS cells. On the other hand, forced over-expression of Ppm1E induced further AMPK inhibition and mTORC1 activation to enhance AGS cell proliferation. Remarkably, microRNA-135b-5p (“miR-135b-5p”), an anti-Ppm1E microRNA, was downregulated in both human gastric cancer tissues and cells. Reversely, miR-135b-5p exogenous expression caused Ppm1E depletion, AMPK activation, and AGC cell proliferation inhibition. Together, Ppm1E upregulation in human gastric cancer is important for cell proliferation, possible via regulating AMPK-mTOR signaling.

Purpose The purpose of this paper is to propose a novel strategy of optimal parameters configuration and placement for sensitive equipment. Design/methodology/approach In this study, clamped thin plate is considered as the foundation form, and a novel composite system is proposed based on the two-stage isolation system. By means of the theory of mechanical four-pole connection, the displacement amplitude transmissibility from the thin plate to precision equipment is derived. For the purpose of performing optimal design of the composite system, a novel multi-objective idea is presented. Multi-objective particle swarm optimization (MOPSO) algorithm is adopted as an optimization technique, which can achieve a global optimal solution (gbest), and selecting the desired solution from an equivalent Pareto set can be avoided. Maximum and variance of the four transmitted peak displacements are considered as the fitness functions simultaneously; the purpose is aimed at reducing the amplitude of the multi-peak isolation system, meanwhile pursuing a uniform vibration as far as possible. The optimization is mainly organized as a combination of parameter configuration and placement design, and the traversal search of discrete plate is performed in each iteration for the purpose of achieving the global optimum. Findings An important transmissibility based on the mechanical four-pole connection is derived, and a composite vibration isolation system is proposed, and a novel optimization problem is also defined here. This study reports a novel optimization strategy combined with artificial intelligence for parameters and placement design of precision equipment, which can promote the traditional view of two-stage vibration isolation. Originality/value Two-stage vibration isolation systems are widely applied to the vibration attenuation of precision equipment, but in these traditional designs, vibration participation of foundation is often ignored. In this paper, participation of foundation of equipment is considered, and a coherent new strategy for equipment isolation and foundation vibration is presented. This study shows a new vision of interdisciplinary including civil engineering, mechanical dynamics and computational science.

Active vibration control based on state feedback using H∞ criterion for two typical types of engineering equipment (machinery and sensitive equipment) is demonstrated here. Semi-active vibration control was implemented using a magnetorheological (MR) damper, which was guided by optimal output using the active method. Two control strategies based on error feedback are introduced here to achieve current regulation for the MR damper. The first method uses a conventional proportional-integral controller. Another method uses an adaptive fuzzy controller to account for the severe nonlinearity and uncertainty of the MR damper. This method is aimed at making improvements in fuzzy logic control for semi-active vibration control. Apart from this, a novel method was implemented to limit current in the case of the sensitive model used to predict output. Particle swarm optimization technique was used to optimize parameters used in this work.

The key-stream generator is the most important algorithm component of the stream cipher and the security of the stream cipher is based on the property of the key-stream generator. At the present, it is still an important development direction of the stream cipher algorithm that the high performance key-stream generators are constructed with complex block cipher algorithms. This paper puts forward the new type of the key-stream generator based on the AES algorithm. This method is based on the OFB mode of the AES algorithm, combined with the variable-step feedback shift. Then the paper analyses the randomness of the key-stream produced by the new key-stream generator. This new key-stream generator really improves the cryptographic properties of the key stream generator and to enhance the security of stream cipher effectively.

The key-stream generator is the most important algorithm component of the stream cipher. At the present, it is an important development direction of the stream cipher algorithm that uses complex block cipher algorithms to construct high performance key-stream generators. The paper puts forward a new design method of the key-stream generator based on the AES algorithm. This method is based on the CFB mode of the AES algorithm, combined with the variable-step feedback shift. Then the paper analyses the randomness of the key-stream produced by the new key-stream generator. This new key-stream generator really improves the cryptographic properties of the key stream generator and to enhance the security of stream cipher.

The increase in the number of private cars as well as non-standard parked behavior has brought great pressure to campus traffic. In order to control this non-standard parked behavior, orderly and reasonable guide and regulate owners to develop good parking habits, we design a vehicle parking violation notification system. A system is designed in the article to record illegal parking information of vehicles. A working principle of this system is that a wireless MMS image terminal captures image information of illegal vehicles, and real-time transmits the captured image information to the Data Center Computer in Security Department of the school through the GPRS network, so as to achieve illegal vehicle information is timely recorded and notified. Meanwhile, outside campus of illegal vehicles will be warned or limited its re-enter the campus. After a year of work and testing, the entire system is stable, and the image information transmission failure rate is very low. Illegal parking behavior on campus has been significantly curbed, and traffic order has been significantly improved.

In order to grasp the whole growth process of breeding cotton and establish the growth records of breeding cotton, the article proposes the design of breeding cotton growth management system based on MMS. The main idea is that field image acquisition terminals capture a live image in breeding cotton plots at a specific time every day, and send the live image to the monitoring center through the GPRS networks, then breeding cotton experts write cotton growth log and propose the next management advice for cotton based on the returned live image. At the same time, all the information will be written to the database in the monitoring center. The application of the system is able to not only save manpower costs, by tracking and analyzing the whole growth process of breeding cotton, but also summarize the successful breeding experience and failures. At the same time, the application of the system promotes cotton breeding and cotton management more scientific. After the actual testing, the system works stable and reliable, and meets the design requirements.

This article presents the design ideas of patrol system based on real-time image acquisition in patrol points. In this system, the image acquisition terminals are mounted on many patrol points, which are set in a predetermined patrol line. When patrol officers arrived at a patrol point, the image acquisition terminal mounted on the patrol point will capture a live image via a GPRS MMS module ,and then the image acquisition terminal sends this image to the central control unit in a form of MMS. The central control unit receives the sent MMS message, and separate out the image information from the received message, and then saves it to a database. According to the actual test results of this patrol system, it can not only meet the design requirements, but also the whole system has a high stability and reliability.

Cross shaft type universal joint is widely used in ground vehicles to transfer torque between two intersecting axes, and its transmission feature can make a great contribution to NVH performance of the vehicle. We looked at the assembling clearance at cross shaft neck, and presented a dynamic model of cross shaft type universal joint with clearance at cross shaft neck. Two-state model is applied to describe the contact force between the cross shaft and driving joint fork based on Hertz theorem, and lumped mass method is applied to build up the dynamic model of the universal joint. Based on this model, numerical analysis is carried out to discuss the transmission feature of the universal joint with clearance at cross shaft neck, and the influence of clearance on the dynamic behavior of the system is evaluated with numerical results based on time history, power spectrum, and phase portrait. The method and conclusions presented are helpful to improvement of the transmission feature of cross shaft type universal joint.

Influences of system parameters on dynamic behavior of the vehicle shimmy system with consideration of clearance in the steering linkage mechanism are analyzed. The kinematic pair of steering linkage mechanism with clearance between the steering tie rod and left trapezoidal arm is modeled based on Hertz’s law, and a four-degree-of-freedom dynamic model of a vehicle shimmy system with consideration of clearance in the steering linkage mechanism is presented. Based on this model, numerical analysis is carried out, and the influences of the parameters, such as clearance, contact surface stiffness of the kinematic pair, wheel alignment parameters, and vehicle speed on the dynamic response of the vehicle shimmy system are discussed. It is shown that, considering the clearance in the steering linkage mechanism, these parameters can make a coupled contribution to the dynamic response of the vehicle shimmy system, and some effective measurements for vehicle shimmy attenuation are available. The conclusions will provide theoretical basis for effective vehicle shimmy control, especially for vehicles which are in use.

This paper chose multi-index to provide a comprehensive evaluation model to evaluate the use reliability of CNC machine tools as a single assessment indicator is biased. As the number of evaluation factors is huge and it is difficult to get the exact values, a fuzzy theory is applied. Reliability mathematical model and maintainability mathematical model were established based on failure data selected from filed test and calculated the estimation values of reliability indexes. Subsequently, a fuzzy comprehensive evaluation mathematical model of CNC machine tools was constructed which combined fuzzy with comprehensive evaluation theory. Using this model could evaluate reliability level of CNC machine tools accurately and integrative.

Correction for ‘A microRNA-4516 inhibitor sensitizes chemo-resistant gastric cancer cells to chemotherapy by upregulating ING4’ by Jun-bao Liu et al., RSC Adv., 2018, 8, 37795–37803.

The planning of the fourth national survey on Chinese materia medica resources shall follow the requirement of "carrying out the national survey on Chinese materia medica resources, strengthening the construction of Chinese materia medica resources monitoring and information network" which is according to the document issued by the State Council. Based on the responsibilities of State Administration of Traditional Chinese Medicine which is "organizing the survey, promoting the resource-protection, keeping development and rational utilization", combined with the key problems that need to be solved in current medicinal industry, the related instructions issued by central leadership and the recommendations from NPC delegates, CPPCC members and experts, the planning shall make overall plans and top-level design for the new round of national survey on Chinese materia medica resources.

Dynamic behavior of the vehicle shimmy system with consideration of steering linkage clearance was analyzed. Based on nonlinear dynamic theories, a 4-DOF dynamic model of vehicle shimmy system with consideration of steering linkage clearance was presented. In which, the revolute movement pair of steering linkage with clearance between the steering tie rod and tie rod arm was described based on Hertz model. Numerical analysis on the dynamic response of the vehicle shimmy system with clearance was carried out, and the results were presented with phase plane, Poincare map, and bifurcation diagram. The dynamic behavior of the vehicle shimmy system with clearance is compared with that without clearance, and the influence of the clearance on the dynamic behavior of the system is discussed, which will provide theoretical basis for attenuation of vehicle shimmy.Copyright © 2012 by ASME

Multi-body dynamic model of a vehicle with leaf spring suspension was established, and road roughness was reconstructed with road surface spectrum. The Root Mean Square (RMS) of acceleration was taken as the evaluation index for optimisation of the ride comfort of the vehicle, and the parameters of the suspension, stiffness and damping coefficient, were optimised. Roadway tests were carried out to verify the presented method, which provided references for the design of suspension with consideration of ride comfort improvement of the vehicle.