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BACKGROUND: Customized prosthetic joint replacements have crucial applications in severe temporomandibular joint problems, and the combined use of porous titanium scaffold is a potential method to rehabilitate the patients. OBJECTIVE: The objective of the study was to develop a design method to obtain a titanium alloy porous condylar prosthesis with good function and esthetic outcomes for mandibular reconstruction. METHODS: A 3D virtual mandibular model was created from CBCT data. A condylar defect model was subsequently created by virtual condylectomy on the initial mandibular model. The segmented condylar defect model was reconstructed by either solid or porous condyle with a fixation plate. The porous condyle was created by a density-driven modeling scheme with an inhomogeneous tetrahedral lattice structure. The porous condyle, supporting fixation plate, and screw locations were topologically optimized. Biomechanical behaviors of porous and solid condylar prostheses made of Ti-6Al-4V alloy were compared. Finite element analysis (FEA) was used to evaluate maximum stress distribution on both prostheses and the remaining mandibular ramus. RESULTS: The FEA results showed levels of maximum stresses were 6.6%, 36.4% and 47.8% less for the porous model compared to the solid model for LCI, LRM, and LBM loading conditions. Compared to the solid prosthesis, the porous prosthesis had a weight reduction of 57.7% and the volume of porosity of the porous condyle was 65% after the topological optimization process. CONCLUSIONS: A custom-made porous condylar prosthesis with fixation plate was designed in this study. The 3D printed Ti-6Al-4V porous condylar prosthesis had reduced weight and effective modulus of elasticity close to that of cortical bone. The

About 20% of angiosperms employ self-fertilization as their main mating strategy. In this study, we aimed to examine how the selfing timing correlated with floral traits in three Gentianopsis species in which autonomous selfing is achieved through filament elongation. Although the three Gentianopsis species exhibit no significant variation in their capacity for autonomous selfing, flowers of G. grandis last longer, are larger and have a higher corolla biomass, P/O ratios and male biomass allocation than those of G. paludosa, and especially those of G. contorta. Autonomous selfing occurs in the early floral life of G. paludosa and G. contorta and in the later floral life of G. grandis. Seed production mainly results from autonomous selfing in G. paludosa and G. contorta; however, G. grandis could be more described as having a mixed mating system. We suggest that autonomous selfing in later floral life increases the chance of cross-pollination prior to this, while autonomous selfing in early floral life offers a selective advantage to plants by reducing the resource investment in traits that may increase pollinator attraction and visitation.

There is discussion over whether pollen limitation exerts selection on floral traits to increase floral display or selects for traits that promote autonomous self‐fertilization. Some studies have indicated that pollen limitation does not mediate selection on traits associated with either pollinator attraction or self‐fertilization. Primula tibetica is an inconspicuous cross‐fertilized plant that may suffer from pollen limitation. We conducted a selection analysis on P. tibetica to investigate whether pollen limitation results in selection for an increased floral display in case the evolution of autonomous self‐fertilization has been difficult for this plant. The self‐ and intra‐morph incompatibility features, the capacity for autonomous self‐fertilization, and the magnitude of pollen limitation were examined through hand‐pollination experiments. In 2016, we applied selection analysis on the flowering time, corolla width, stalk height, flower tube length, and flower number in P. tibetica by tagging 76 open‐pollinated plants and 37 hand‐pollinated plants in the field. Our results demonstrated that P. tibetica was strictly self‐ and intra‐morph incompatible. Moreover, the study population underwent severe pollen limitation during the 2016 flowering season. The selection gradients were found to be significantly positive for flowering time, flower number, and corolla width, and marginally significant for the stalk height. Pollinator‐mediated selection was found to be significant on the flower number and corolla width, and marginally significant on stalk height. Our results indicate that the increased floral display may be a vital strategy for small distylous species that have faced difficulty in evolving autonomous self‐fertilization.

Distyly is a widespread floral polymorphism characterized by the flowers within a population showing reciprocal placement of the anthers and stigma. Darwin hypothesizes that distyly evolves to promote precise pollen transfer between morphs. Primula chungensis exhibits two types of anther heights, and these two types of anthers show pollen of two different size classes. To understand whether the stigma could capture more pollen grains from the anthers of the pollen donor as the separation between the stigma of pollen receiver and the anther of pollen donor decreased, the present research assessed the source of the pollen load in a series of open-pollinated flowers with continuous variation of style lengths. Individuals with continuous variation of style length were tagged, and the selected flowers in the tagged plants were emasculated the day before dehiscence. The stigma of the emasculated flowers was fixed in fuchsin gel at the end of blooming. We assessed the pollen sources on each stigma by taking photos under a microscope and measured the diameter of each conspecific pollen grain with ImageJ. We found that a shorter distance from the stigmas to the anthers of a pollen donor gave the flower a higher capacity to receive pollen from those anthers. Our result provides a new evidence that distyly could promote the pollen transfer between morphs, which is consistent with Darwin’s hypothesis of disassortative pollination. An alternative hypothesis for the evolution of distyly (e.g. selfing avoidance) might also be true, but less likely, because self-incompatibility would greatly avoid self-fertilization for many distylous species., Distyly, a well-known floral syndrome that was first identified by Charles Darwin, would be an ideal model to determine how a key floral syndrome is shaped by nature. Primula chungensis, a distylous species with simultaneous homo-, short- and long-styled morphs, exhibits some variations in the length of style. Using this species, we found that the stigma captured more compatible pollen as the separation between the stigma of the pollen receiver and the anther of the pollen donor decreased. Our results provide clear and novel evidence for the disassortative pollination hypothesis proposed by Charles Darwin, which will be helpful for our future understanding of the evolution of distyly.

Background The purpose of this study was to design a customized fixation plate for mandibular angle fracture using topological optimization based on the biomechanical properties of the two conventional fixation systems, and compare the results of stress, strain and displacement distributions calculated by finite element analysis (FEA). Methods A three-dimensional (3D) virtual mandible was reconstructed from CT images with a mimic angle fracture and a 1 mm gap between two bone segments, and then a FEA model, including volume mesh with inhomogeneous bone material properties, three loading conditions and constraints (muscles and condyles), was created to design a customized plate using topological optimization method, then the shape of the plate was referenced from the stress concentrated area on an initial part created from thickened bone surface for optimal calculation, and then the plate was formulated as “V” pattern according to dimensions of standard mini-plate finally. To compare the biomechanical behavior of the “V” plate and other conventional mini-plates for angle fracture fixation, two conventional fixation systems were used: type A, one standard mini-plate, and type B, two standard mini-plates, and the stress, strain and displacement distributions within the three fixation systems were compared and discussed. Results The stress, strain and displacement distributions to the angle fractured mandible with three different fixation modalities were collected, respectively, and the maximum stress for each model emerged at the mandibular ramus or screw holes. Under the same loading conditions, the maximum stress on the customized fixation system decreased 74.3, 75.6 and 70.6% compared to type A, and 34.9, 34.1, and 39.6% compared to type B. All maximum von Mises stresses of mandible were well below the allowable stress of human bone, as well as maximum principal strain. And the displacement diagram of bony segments indicated the effect of treatment with different fixation systems. Conclusions The customized fixation system with topological optimized structure has good biomechanical behavior for mandibular angle fracture because the stress, strain and displacement within the plate could be reduced significantly comparing to conventional “one mini-plate” or “two mini-plates” systems. The design methodology for customized fixation system could be used for other fractures in mandible or other bones to acquire better mechanical behavior of the system and improve stable environment for bone healing. And together with SLM, the customized plate with optimal structure could be designed and fabricated rapidly to satisfy the urgent time requirements for treatment.

It remains poorly understood if carrier hardness, elastic modulus, and contact area affect neural stem cell growth and differentiation. Tensile tests show that the elastic moduli of Tiansu and SMI silicone membranes are lower than that of an ordinary dish, while the elastic modulus of SMI silicone membrane is lower than that of Tiansu silicone membrane. Neural stem cells from the cerebral cortex of embryonic day 16 Sprague-Dawley rats were seeded onto ordinary dishes as well as Tiansu silicone membrane and SMI silicone membrane. Light microscopy showed that neural stem cells on all three carriers show improved adherence. After 7 days of differentiation, neuron specific enolase, glial fibrillary acidic protein, and myelin basic protein expression was detected by immunofluorescence. Moreover, flow cytometry revealed a higher rate of neural stem cell differentiation into astrocytes on Tiansu and SMI silicone membranes than on the ordinary dish, which was also higher on the SMI than the Tiansu silicone membrane. These findings confirm that all three cell carrier types have good biocompatibility, while SMI and Tiansu silicone membranes exhibit good mechanical homogenization. Thus, elastic modulus affects neural stem cell differentiation into various nerve cells. Within a certain range, a smaller elastic modulus results in a more obvious trend of cell differentiation into astrocytes.

Postoperative hypoparathyroidism due to dysfunction of the parathyroid gland is the most common complication after thyroidectomy. Our objective was to introduce the method of anatomical localization of normal parathyroid glands before thyroidectomy through ultrasonography and to evaluate its efficiency. The study group included 52 patients subjected to anatomical localization of the parathyroid gland prethyroidectomy through ultrasonography. The control group included 52 sex- and age-matched patients without parathyroid gland localization. The proportion of parathyroid glands preserved in situ and postoperative hypoparathyroidism rates in the 2 groups were compared. The rates of normal parathyroid glands identified according to ultrasonography for left superior, left inferior, right superior, and right inferior glands were 78.8%, 90.4%, 57.7%, and 82.7%, respectively. The rate of parathyroid gland excised inadvertently was significantly decreased (P = .038) in the study group as compared with the control group. The rates of parathyroid gland preservation in situ were significantly improved in the left superior (P = .001), left inferior (P = .002), and right inferior glands (P = .005). Furthermore, the incidence of transient hypoparathyroidism decreased significantly (P = .028). Our study indicated that normal parathyroid glands were identified by ultrasonography, and the anatomical localization improved the rate of parathyroid gland preservation in situ and decreased the incidence of transient hypoparathyroidism.

When designing the air nailer, in order to achieve the purpose of rapid analysis of design results, use of VB and APDL tools, secondary development of ANSYS, established a parametric CAE analysis module, template-based CAE analysis module, and profession CAE analysis module. And this three module is integrated into the air nail industrial design platform. As a result, designers can quickly and easily on the air nailer for CAE analysis. Meanwhile, in order to achieve in the 3D design of the system of the air nailer’s handle for comfort evaluation, an evaluation method is proposed. Analysis and demonstrated the principle of the method. Established a comfort evaluation model. On this basis, comfortable evaluation software is developed. Evaluation results generated by the software can be used as a reliable basis for revising shapes of handles.

Based on requirements of evaluation on comfort level of hand-held tool handles, this essay put forward an evaluation method as well as analyzed and proved its principle, established a corresponding evaluation mode, deliberated index and computation module for comfort level of tool handles. The authored also developed a set of software to evaluate comfort level of tool handles. With this software, one can efficiently evaluate the comfort level of tool handles and an evaluation report will be made automatically, which can serve as a reliable basis for revising shapes of handles.

Digital industrial design system combines the digital technology and industrial design process，and integrates the sub-systems of digital modeling, digital assemble, digital evaluation, digital manufacture, and digital information exchange. In order to let the industrial design work process and the design data flowing fluently around such sub-systems, Product Data Management (PDM) system is introduced here as the basic integration platform of the sub-systems to let the design process flow and design data flow working well. The product digital industrial design platform basic functions and its system structure is analyzed, and a general model and function frame of product data management system oriented to digital industrial design is presented in this paper to solve its characteristic data composition, integrative method of application software and industrial design flow in the process of the digital industrial design. Results about the working process integrative model, control process model, product class definition model, and the logical structure of the digital industrial design platform with the PDM system are also established. An application results for certain product development show that such digital industry design system can make the helps for the design work efficiency and the follow-up engineering design accuracy.

Computer Aided Industrial Design System is a key component of the product digital design platform. It is equally important to control its design process and manage its data and documents effectively to share the data generated in the whole design process. Based on the analysis of the basic functions of the product digital industrial design platform, this paper presents the general model and function frame of product data management system oriented to computer aided industrial design according to its data composition character, integrative method of application software and industrial design flow in the process of computer aided industrial design. In addition, with the industrial design of the pneumatic tools as the object, this paper presents the product data management system to achieve the system integration of computer aided industrial design, 3-D structure design and CAE analysis and the data share.

The all processes for manufacturing materials parts of solid oxide fuel cell (SOFC) are discussed in the paper. The films are made in one step by the ways of APS, VPS, EVD, which are usually used to produce the electrolyte and interconnect. The films are thin and good gas-resistance, but with relatively high cost. All parts of SOFC are made by the following ways, such as sol-gel, tape casting, tape calendaring and screen printing, which are suitable for manufacturing samples in industry with the cheapest process by co-sintered together ways.

Heterostyly is a floral polymorphism characterized by reciprocal herkogamy maintained through high levels of mating between morphs, serviced by appropriate pollinators. We studied how differential efficiency and abundance of distinct pollinators affect plant female reproduction in self- and intra-morph incompatible distylous Primula secundiflora. Bumblebees and syrphid flies were found to be the most abundant floral visitors. Bumblebees frequently exhibited nectar-robbing behavior. Because the robbing holes were always situated between the high- and low-level organs on both morphs, nectar-robbing bumblebees only pollinated S-styled flowers. L-styled flowers set four times as many seeds as did S-styled flowers after being visited by pollen-collecting syrphid flies. The natural female fecundity and the magnitude of pollen limitation varied between the morphs within populations because of the mosaic distribution of nectar-robbing bumblebees and syrphid flies. L-styled flowers and S-styled flowers set the same number of seeds after supplemental hand pollination, indicating equivalent female reproductive potential. We suggest that bumblebee nectar robbers and syrphid flies play an important role in sustaining the floral dimorphism of heterostyly in P. secundiflora because of their complementary roles in the pollination system.