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In order to obtain a lightweight, high-strength, and customizable cellular structure to meet the needs of modern production and life, the mechanical properties of four thickness gradient honeycomb structures were studied. In this paper, four types of honeycomb structure specimens with the same porosity and different Poisson's ratios were designed and manufactured by using SLA 3D-printing technology, including the honeycomb, square honeycomb, quasi-square honeycomb, and re-entrant honeycomb structures. Based on the plane compression mechanical properties and failure mode analysis of these specimens, the thickness gradient is applied to the honeycomb structure, and four structural forms of the thickness gradient honeycomb structure are formed. The experimental results show that the thickness gradient honeycomb structure exhibits better mechanical properties than the honeycomb structure with a uniform cellular wall thickness. In the studied thickness gradient honeycomb structure, the mechanical properties of the whole structure can be significantly improved by increasing the thickness of cell walls at the upper and lower ends of the structure. The wall thickness, arrangement order, shape, and Poisson's ratio of the cell all have a significant impact on the mechanical properties of the specimens. These results provide an effective basis for the design and application of cellular structures in the future. [ABSTRACT FROM AUTHOR]

In order to reduce the weight of the panels used in buildings and minimize the use of wood, it is of great practical significance to study the mechanical properties of wood-based sandwich structures for adaptation to modern wood-structured buildings. In this paper, a wood-based pyramid structure specimen with large interconnection space was designed and prepared first. Based on the results of the flat compression, in order to strengthen the core layer of the sandwich structure, an interlocking grid structure can be used. The mechanical properties of two kinds of structure specimens, including bearing capacity, compressive strength, specific strength, load–mass ratio, safety factor distribution, and specific energy absorption, were studied by means of experimental test, theoretical analysis, and finite element analysis. It was concluded that the apparent density of the two structures was lower than that of the materials of which they were composed. However, the overall flat compressive strength of the two structures was higher than that of their constituent materials, which were high-strength materials in the field of natural materials. The mechanical properties of the interlocking grid structures were better than those of the pyramid structures. Based on the criterion of cell structure stability, it can be concluded that the wood-based pyramid structure was a flexural-dominant structure, and the interlocking grid structure was a tensile-dominant structure. The results show that the core layer design plays an important role in the mechanical properties and failure modes of wood-based sandwich structures. [ABSTRACT FROM AUTHOR]

Summary: Our study aimed to clarify the correlation between miR‐1247‐5p expression and clinicopathological parameters and survival of patients with breast cancer (BC). We evaluated the expression level of miR‐1247‐5p in 224 formalin‐fixed, paraffin‐embedded specimens (112 BC and matched cancer free tissues) by quantitative real‐time reverse transcriptase polymerase chain reaction (qRT‐PCR). miR‐1247‐5p expression in BC tissues was found to be decreased compared with matched normal tissues (P < 0.01). Additionally, low miR‐1247‐5p expression in BC tissues was significantly associated with the advanced TNM stage (P = 0.007), lymph node metastasis (P = 0.015), poorer pathological differentiation (P = 0.005) and molecular subtype (P = 0.027). The patients in the low miR‐1247‐5p group had a shorter disease‐free survival and overall survival than those in the high miR‐1247‐5p group (P < 0.01). Furthermore, the univariate and the multivariate analyses showed that miR‐1247‐5p expression was an independent predictor of overall survival (P < 0.01). Our study showed that miR‐1247‐5p was related to the biological behaviour of breast tumour and prognosis of patients with BC. miR‐1247‐5p could be a novel tumour suppressor and act as a potential biomarker and therapeutic agent for breast carcinoma. [ABSTRACT FROM AUTHOR]

The article discusess a study conducted for analysing utility of totally implantable venous access ports in patients with breast cancer. The study showed that totally implantable venous access port implantation through internal jugular vein or subclavian puncture without ultrasonic guide was safe and feasible for the breast cancer patients during adjuvant treatment and followup.

Examines the phenylalanine biosynthesis in Brevibacterium lactofermentum using Escherichia coli genes pheA, aroG and tyrB. Process of encoding 3-deoxy-D-arabino-heptulosonate-7-phosphate synthetase; Amplification of several genes by polymerase chain reaction; Activities of the enzyme in the host cells.

In order to obtain a lightweight, high strength, and large design space wooden sandwich structure to meet the needs of modern wooden buildings, the mechanical properties of a fabricated 2D wooden pyramid lattice sandwich structure were studied. In this paper, the mechanical and compressive properties of the specimens with different arrangement of Lattice Sandwich unit cells are studied. The upper and lower panels and core materials are made into a single unit cell by inserting glue, and the prefabricated 2D wooden pyramid lattice truss core sandwich structure is prepared by the mortise tenon splicing method. The results show that the arrangement of the unit cells in the specimen has a significant effect on the bearing capacity, energy absorption, and failure mode of the specimen, and the flat compression performance of the panel-reinforced specimen is better than that of the specimen with unreinforced veneer. The results of finite element analysis are consistent with the test results. The main failure modes are core fracture and panel cracking. These results provide a theoretical basis for the system design of wood-based lattice sandwich structure in the future. [ABSTRACT FROM AUTHOR]