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When the characteristic structure size of the component is at the micron level, the internal crystal grains, grain boundaries, and pore defects of the component material with the same size at the micron level cannot be ignored, so the micro-sized component will show different physical properties from the macro-sized component, which is called size effect. Since the tool diameter of a micro-end mill is in the micron level, the micro-end mill will also show a significant size effect phenomenon. In addition, in the micro milling process, because the surface roughness that affects the performance and service life of micro parts is mainly influenced by the vibration of the micro-end mill, in order to enhance the machined surface quality, it is crucial to research the formation mechanism of surface topography in the micro milling process. In this paper, a comprehensive method is proposed to predict micro-end mill vibration, micro milling force, and surface roughness. At first, a size-dependent dynamic model of micro-end mill is presented based on the strain gradient elasticity theory (SGET). Secondly, considering the feedback of a micro-end mill vibration, the micro milling force model is presented and solved through the iterative method. Then the machined surface topography is simulated through the actual cutting edge trajectory considering the micro-end mill size-dependent vibration and material elastic recovery. The results show that the vibration of the micro-end mill will increase the micro milling force and surface roughness. In order to verify the accuracy and efficiency of the presented method, experiments are performed, and it is found that the predicted results are consistent with the experimental results. [ABSTRACT FROM AUTHOR]

Cuticular waxes, long-chain hydrocarbon compounds, form the outermost layer of plant surfaces in most terrestrial plants. The presence of cuticular waxes protects plants from water loss and other environmental stresses. Cloning and characterization of genes involved in the regulation, biosynthesis, and extracellular transport of cuticular waxes onto the surface of epidermal cells have revealed the molecular basis of cuticular wax accumulation. However, intracellular trafficking of synthesized waxes to the plasma membrane for cellular secretion is poorly understood. Here, we characterized a maize glossy (gl6) mutant that exhibited decreased epicuticular wax load, increased cuticle permeability, and reduced seedling drought tolerance relative to wild-type. We combined an RNA-sequencing-based mapping approach (BSR-Seq) and chromosome walking to identify the gl6 candidate gene, which was confirmed via the analysis of multiple independent mutant alleles. The gl6 gene represents a novel maize glossy gene containing a conserved, but uncharacterized, DUF538 domain. This study suggests that the GL6 protein may be involved in the intracellular trafficking of cuticular waxes, opening the door to elucidating the poorly understood process by which cuticular wax is transported from its site of biosynthesis to the plasma membrane. [ABSTRACT FROM AUTHOR]

A significant size effect will occur on the tool part of micro-end mill due to its small diameter, which means the internal structure of the tool part material will affect the mechanical properties of the tool part. In view of this, a comprehensive method considering size effect is proposed in this paper to predict both the static and dynamic behaviors of micro-end mill more accurately. Based on the strain gradient elasticity theory (SGET) and Hamilton's principle, dynamic model of micro-end mill tool is presented, in which the Timoshenko beam model (TBM) considering the shear deformations and rotary inertia effects is employed. Based on the presented model, the static and dynamic behaviors of micro-end mill is obtained utilizing the finite element method (FEM). The influences of size effect on micro-end mill are investigated in detail by contrasting the static and dynamic behaviors of micro-end mill with different tool diameters and different length-to-diameter ratios, respectively. In order to verify the accuracy and efficiency of the presented method, an improved experiment is performed in this paper. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the feasibility of ileal ureter replacement combined with Boari flap-psoas hitch procedure for the management of full-length ureteral defects (>20 cm).Methods: Three patients diagnosed with full-length ureteral defect were treated with our technique performed by a single surgeon between January 2015 to January 2016. All the patients had borderline renal function preoperatively. In each case, the ureteral reconstruction was performed by combining ileal ureter replacement with Boari flap-psoas hitch. Data on indications for surgery, intraoperative and postoperative outcomes, and changes in renal function were collected.Results: Surgery was performed successfully with an operation duration between 210 and 250 minutes. The mean estimated blood loss was 230 mL. The mean length of hospital stay was 11 days, and no major complications (grade ≥3) occurred. Postoperative follow-up showed radiological resolution of hydronephrosis and improved renal function in all 3 patients.Conclusion: Ileal ureter replacement combined with Boari flap-psoas hitch is a feasible option for bridging full-length ureteral defects. This technique minimizes the length of ileal graft required as well as limitations concerning patient selection. Larger series with longer follow-up to confirm the value of the technique are warranted. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the feasibility of an internal suspension technique in retroperitoneal laparoscopic partial nephrectomy for the management of renal ventral tumors. Methods. Between January 2013 and July 2016, a total of 145 patients underwent retroperitoneal laparoscopic partial nephrectomy with or without internal suspension technique. For patients who underwent internal suspension technique, the surgeons preserved the external fat of the renal tumor as a suspension traction measure when separating the kidney. Propensity score matching (PSM) was performed according to age, gender, body mass index, tumor size, tumor location, and RENAL nephrometry score. Patient characteristics and intraoperative and postoperative outcomes were compared between the groups. Results. After PSM, 32 patients treated with the internal suspension technique were compared with 32 cases treated without such technique. Baseline characteristics were statistically similar for the cohorts. The use of our new technique resulted in shorter warm ischemia time (WIT: 15.0 versus 19.0 minutes, P=.002) and tumor resection time (4.0 versus 7.5 minutes, P<0.001). The rate of WIT >25 minutes decreased (6.3% versus 25%, P=.04) and the trifecta outcomes were significantly improved (87.5% versus 62.5%, P=.02). Conclusion. Internal suspension technique is a feasible and safe procedure in retroperitoneal laparoscopic partial nephrectomy for renal ventral tumors. [ABSTRACT FROM AUTHOR]

• Clarifying grain-scale material removal mechanisms in micro-cutting processes. • Analyzing grain orientation effects on the primary slip system and machinability. • Discussing grain boundary effects through crystallographic and orientation features. • Revealing grain size effects via the number of grains and boundaries in affected zone. Crystalline material miniature parts are highly required under the development trend of miniaturization in some fields, and micro-cutting is a promising technology to manufacture complex-shaped crystalline material miniature parts. In the micro-cutting process of crystalline materials, the cutter edge radius, cutting parameters and grain size are in the same order of magnitude, and the workpiece has significant microstructure heterogeneity and mechanical property anisotropy. Therefore, the "cutter edge size effect" and "microstructure effect" occur during the micro-cutting process of crystalline materials, which make it difficult to predict the material deformation behavior and machinability, leading to low efficiency and poor accuracy in the manufacturing process of crystalline material miniature parts, and seriously restricting their widespread application. Taking Inconel-718 as the example, the influence of grain orientation, grain boundary and grain size on the micro-cutting machinability of crystalline materials are comprehensively investigated through single-crystal, bi-crystal and polycrystalline orthogonal micro-cutting simulations. Results show that, grain orientation affects the slip system and slip degree during micro-cutting processes, which leads to different material deformation behaviors. The influence of grain boundary on material behaviors in micro-cutting processes can be divided into two aspects i.e., the material response across grain boundary introduced by its presence and the response difference caused by the difference of grain boundaries. Grain boundary features like grain boundary misorientation angle, grain boundary interface orientation, the number deviation of primary slip systems and the Schmid factor deviation of primary slip systems significantly influence the micro-cutting machinability. Besides, grain size affects the micro-cutting machinability by influencing the number of grains, slip systems and grain boundaries involved in the affected zone. Clarified mechanisms can be used as a credible basis to predict the machinability of crystalline materials in micro-cutting processes, and improve the manufacturing efficiency and quality of crystalline material miniature parts. [Display omitted] [ABSTRACT FROM AUTHOR]

Preharvest sprouting reduces the maize quality and causes a significant yield loss in maize production. vp-wl2 is a Mutator (Mu)-induced viviparous mutant in maize, causing white or pale yellow kernels, dramatically reduced carotenoid and ABA content, and a high level of zeta-carotene accumulation. Here, we reported the cloning of the vp-wl2 gene using a modified digestion-ligation-amplification method (DLA). The results showed that an insertion of Mu9 in the first intron of the zeta-carotene desaturase (ZDS) gene results in the vp-wl2 mutation. Previous studies have suggested that ZDS is likely the structural gene of the viviparous9 (vp9) locus. Therefore, we performed an allelic test using vp-wl2 and three vp9 mutants. The results showed that vp-wl2 is a novel allele of the vp9 locus. In addition, the sequences of ZDS gene were identified in these three vp9 alleles. The vp-wl2 mutant gene was subsequently introgressed into four maize inbred lines, and a viviparous phenotype was observed with yield losses from 7.69% to 13.33%. [ABSTRACT FROM AUTHOR]

The effect of traffic flow prediction plays an important role in routing selection. Traditional traffic flow forecasting methods mainly include linear, nonlinear, neural network, and Time Series Analysis method. However, all of them have some shortcomings. This paper analyzes the existing algorithms on traffic flow prediction and characteristics of city traffic flow and proposes a road traffic flow prediction method based on transfer probability. This method first analyzes the transfer probability of upstream of the target road and then makes the prediction of the traffic flow at the next time by using the traffic flow equation. Newton Interior-Point Method is used to obtain the optimal value of parameters. Finally, it uses the proposed model to predict the traffic flow at the next time. By comparing the existing prediction methods, the proposed model has proven to have good performance. It can fast get the optimal value of parameters faster and has higher prediction accuracy, which can be used to make real-time traffic flow prediction. [ABSTRACT FROM AUTHOR]