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According to the characteristics and application of 3D printing technology, the problems to be faced in the process of equipment maintenance and rush repair are analyzed, and the advantages of 3D printing technology for equipment maintenance and rush repair are summarized. Moreover, the phenomenon analysis, finite element analysis and analysis optimization are carried out in combination with the vulnerable parts in large engineering equipment. To provide data samples based on FDM 3D printing technology in equipment maintenance and rush repair, explore potential applications.

With the continuous deepening of reform in military academies, more and more ambitious individuals have joined military academies through civilian recruitment exams to become civilian instructors. Civilian instructors have become an indispensable part of the construction of military academies. Due to their special professional identity attributes, coupled with the lack of understanding of the military, work habits, and weak teaching foundation of civilian personnel recruited from the society, their ability improvement is relatively slow. The current situation of civilian teachers is unclear in their own positioning, the team is young and inexperienced, and the training system is incomplete. They still lack a lot of experience in training, leading, speaking, and competitions. This article analyzes from three aspects: changing identity, learning and helping, and practicing through competition, actively adapting to the environment, grasping the first 3-5 years, and achieving rapid improvement in abilities.

The crossbeam plays a vital role in computer numerical controlled milling machines, especially in machines with a gantry structure, as it directly influences the machining precision. In this study, a machine tool crossbeam was designed, and the modal frequency of the crossbeam was analyzed using the finite element model (FEM) analysis. In the improved structure obtained through FEM analysis, the X-type structure of the internal unit of the crossbeam was replaced by an O-type structure. The specific structure dimensions were further optimized using a neural-network algorithm and a nondominated sorting genetic algorithm. Finally, we calculated the effect of each crossbeam dimension on the mass, deformation, and frequency in a sensitivity analysis. After optimizing the crossbeam dimensions with respect to deformation, modal frequency, and mass, the structural characteristics of the original and optimized crossbeams were compared. After optimization, the mass and deformation were reduced by 7.45% and 3.08%, respectively, and the modal frequency was increased by 0.42%. These results confirm that the optimization improved the performance of the crossbeam structure.

In this report, two new redox-responsive complexes with different dendritic tail chain number (P4VP- nFc, n = 1, 2) were prepared via the hydrogen-bonded self-assembly of poly(4-vinylpyridine) and ferrocenyl-modified percec-type dendrons. These complexes exhibited a crystalline phase for P4VP-1Fc and liquid crystalline for P4VP-2Fc at room temperature. The cyclic voltammetry measurement shows that the electrode process of P4VP-nFc (n = 1, 2) films was diffusion controlled and the reversibility of the electrode process for the P4VP-2Fc films became better than that for the P4VP-1Fc. Moreover, the redox peak current |ip| increased with increasing dendritic tail chain number n in the complex, because the complex film formed with 2Fc-COOH has the looser stacking of alkyl chains, which was favorable for the electrolyte diffusion and charge transfer. The present results demonstrate that the electrochemical activity of the redox-responsive poly(4-vinylpyridine) -ferrocenyl dendron complex can be easily tuned using the dendritic tail chain with different numbers. These complexes may be used as new kinds of modified electrodes.

Study of methods to design optimal Gough–Stewart parallel manipulator geometries meeting orthogonality is of high interest. The paper will design the Orthogonal Generalized Gough-Stewart Parallel Manipulator (OGGSPM) based on the composite hyperboloids. Moreover, Particle Swarm Optimization (PSO) algorithm is introduced to perform the structure optimization as the Jacobian matrix condition number is used as the evaluation index. As an example, two different optimization cases are presented.

Two kinds of ionic self-assembled complexes of linear or branched poly(ethyleneimine) (lPEI or bPEI) with Percec-type dendrons [(3,4,5)16G1-COOH] were prepared as lPEI-(3,4,5)16G1-x and bPEI-(3,4,5)16G1-x, where x is the mole ratio of the carboxyl groups of the dendritic amphiphile to the amino groups at the PEI chain. The crystal and mesomorphous structures and thermal properties of these complexes were investigated with X-ray diffraction (XRD), Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), and polarized optical microscope (POM). Both the lPEI and bPEI complexes exhibited the same αH crystal phase and similar lamellar mesomorphous phase, irrespective of the branching of the polymer backbone and the binding degree. The lPEI series complexes lPEI-(3,4,5)16G1-x, however, had more ordered lamellar stacking than that of the bPEI-(3,4,5)16G1-x complexes, so the thermotropic liquid crystal phase SmA was formed only in the lPEI-(3,4,5)16G1-x complexes beyond the melting point of the tail crystal of the dendritic amphiphile. No liquid crystalline phase was found from the bPEI-(3,4,5)16G1-x complexes. The results suggest that the branching of polymer backbone plays a key role to the formation of thermotropic liquid crystal in the polymer–dendritic amphiphile complex. The present finding is significant for the design of functional nanostructures based on the ionic complexation of polymers and amphiphiles. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011

Complement forms a key arm of innate immune defenses against gonococcal infection. Sialylation of gonococcal lipo-oligosaccharide, or expression of porin 1A (Por1A) protein, enables Neisseria gonorrhoeae to bind the alternative pathway complement inhibitor, factor H (fH), and evade killing by human complement. Using recombinant fH fragment-murine Fc fusion proteins, we localized two N. gonorrhoeae Por1A-binding regions in fH: one in complement control protein domain 6, the other in complement control proteins 18–20. The latter is similar to that reported previously for sialylated Por1B gonococci. Upon incubation with human serum, Por1A and sialylated Por1B strains bound full-length human fH (HufH) and fH-related protein 1. In addition, Por1A strains bound fH-like protein 1 weakly. Only HufH, but not fH from other primates, bound directly to gonococci. Consistent with direct HufH binding, unsialylated Por1A gonococci resisted killing only by human complement, but not complement from other primates, rodents or lagomorphs; adding HufH to these heterologous sera restored serum resistance. Lipo-oligosaccharide sialylation of N. gonorrhoeae resulted in classical pathway regulation as evidenced by decreased C4 binding in human, chimpanzee, and rhesus serum but was accompanied by serum resistance only in human and chimpanzee serum. Direct-binding specificity of HufH only to gonococci that prevents serum killing is restricted to humans and may in part explain species-specific restriction of natural gonococcal infection. Our findings may help to improve animal models for gonorrhea while also having implications in the choice of complement sources to evaluate neisserial vaccine candidates.

Mammalian sperm contain a single large secretory vesicle, or acrosome. Exocytosis of this vesicle (the acrosome reaction) occurs as an early step in the gamete interaction process and is an essential prerequisite for late events, including sperm-egg fusion [1]. The control of fertilization is, from this perspective, a question of the regulation of a secretory event. It may be useful to compare sperm to other secretory systems. Typical somatic secretory cells such as mast cells, the neuronal presynaptic terminal, and exocrine cells contain large numbers of secretory vesicles whereas sperm possess a single acrosome. Those familiar somatic secretory models tolerate a low level of basal vesicle release that is augmented upon the arrival of an external stimulus. For example, miniature synaptic potentials are due to the stochastic release of individual vesicles, and stimuli, in the form of membrane depolarization, increase the number of released vesicles [2, 3]. In contrast, it can be argued that spontaneous exocytosis must be strictly controlled in sperm and may require a specialized regulatory mechanism. Key elements in this argument include the observations that 1) sperm that complete the acrosome reaction at a distance from eggs have decreased capacity to penetrate through the cumulus oophorus [4] and to adhere to the egg’s extracellular matrix, or zona pellucida [5, 6], and 2) sperm that fail to initiate acrosome reactions cannot penetrate the zona pellucida and hence are denied access to the egg plasma membrane [1]. Sperm consequently face an ‘‘acrosome reaction problem,’’ in which secretion must be coordinated with egg contact and yet spontaneous secretory rates must be suppressed. It is now understood that the initiation of acrosome reactions during egg contact is accomplished by the presence in the zona pellucida of an acrosome reaction-inducing agonist, the glycoprotein ZP3 [7]. However, individual sperm must still prevent spontaneous secretion until the time of sperm-egg contact. One common theme in the regulation of exocytotic processes is the general role of intracellular Ca21 ([Ca]i) as a mediator of stimulus-secretion coupling. In both sperm and somatic cells, elevations of [Ca]i are necessary and

with the provincial panel data of the western region of China from 2000 to 2009, this paper establishes a regression model and uses pooled-LS analysis and MCMC algorithm which based on Bayesian linear regression theory to empirical analysis the financial development in the western region of China upon the urban-rural income gap. The result shows that the development of financial intermediation widens the income gap of urban-rural, however, the development of insurance market has an opposite impact on the urban-rural income gap. At last, this paper explains the reasons behind this and some suggestions are given here.

The genus Capricornis was widely distributed in Asia. In the present study, the complete mitochondrial genome of Capricornis sp., possible a new species of Serow from Guizhou province of China, was sequenced for the first time. Sequence analysis showed it is 16,441 bp in length, consisting of 12S rRNA gene, 16S rRNA gene, 22 transfer RNA (tRNA) genes, 13 protein-coding genes and one control region (CR).

A novel ferroceneylazobenzene self-assembled monolayer (SAM) has been constructed on an indium-tin oxide (ITO) electrode via the covalent attachment of 4-(4'-11-ferrocenyl-undecanoxyphenylazo)benzoic acid ( FcAzCOOH) onto a silanized ITO substrate surface and verified by reflectance infrared spectroscopy and water contact angle. Atomic force microscopy (AFM) and cyclic voltammogram (CV) indicated that the FcAzCOOH formed a uniform and reproducible SAM on the ITO electrode with a surface coverage of ca. 1.9 x 10 (-10) mol/cm (2) (87 A (2)/molecule). The reversible photoisomerization behavior of the SAM was characterized by UV-vis spectra. The azo pi-pi* transition band intensity of the SAM gradually decreased with UV (365 nm) irradiation and was almost recovered again when subsequent exposure to ambient room light (400-800 nm). The increased tilt angle of the molecules on the ITO substrate after UV irradiation further confirmed the trans-to- cis isomerization of azobenzene moieties. The CV of the trans- FcAzCOOH modified ITO electrode showed a pair of waves due to redox of the ferrocene groups in the potential range of 0 to +800 mV (vs SCE), and the peak separation of the redox wave became larger after UV irradiation and almost returned to its original value after subsequent exposure to the visible light. Rate-dependent CV curves indicated that the charge transfer rate between the ferrocene species in the SAM and the ITO electrode was slowed down after UV irradiation due to the smaller porosity of the monolayer film and the more compact barrier layer between the redox species and the ITO electrode. It is the first time to directly observe the influence of photoisomerization of the azobenzene moiety on the redox behavior of redox species in the ferroceneylazobenzene-functionalized SAM. The present results provide profound insight into the role of redox microenvironment on electron transfer kinetics and also provide a simple and facile approach to the preparation of photocontrollable electrodes.