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1.
Composite biomaterials are in high demand in the medical field of today. The combination of bioactive wollastonite (WA) glass ceramic with the biocompatibility of alloy titanium (Ti6Al4V) could be a good candidate for implant applications. The rheological properties of Ti6Al4V/WA feedstock show a pseudoplastic behaviour with low activation energy. The feedstock was successfully injected as a green part with no defects. The green part was solvent debound for 6?h in heptane and thermal debound in an argon environment for 1?h. The brown part was successfully sintered at 1300?°C for 3?h with 5?°C/min heating and cooling rates. The average sintered density was 4.12?g/cm3; which is 97.5% from the theoretical density. The highest Young's modulus obtained was 18.10?GPa; which is in the range of human bone strength. EDX analysis shows that by increasing sintering temperature, the level of oxygen decreased. Cell viability test shown an absorbance increased with days increasing indicated that the cellular were proliferated on the composite Ti6Al4V/WA composite which also proved that the composite was non-toxic. This indicates that the Ti6Al4V/WA composite is suitable for bone implant applications.  相似文献   
2.
Using metallic materials in automotive structures increases weight, fuel consumption and cost, therefore, certain trends have begun to use lightweight and cheaper materials. Fibre composites are used in automotive applications because they are stiff, lightweight and stronger than bulk material, as well as they have a comparable energy-absorbing capacity to that of metallic materials. The aim of this study is to investigate the potentials in natural ramie/bio-epoxy composite in crash energy absorption applications. Cubic specimens consisted of 12, 24 and 30 plies of ramie/bio-epoxy laminates with 50, 80 and 120 mm long which were prepared by hand layup method. Static axial compression load was then applied and the energy-absorbing capability of the ramie/epoxy composite was evaluated. The crashworthiness characteristics of the composite tubes were evaluated by measuring the average and peak crushing load, specific energy absorption, total absorbed energy and crush force efficiency in quasi-static axial compression. The failure mode and behaviour of the tubes were investigated by taking photographs and recording the load–displacement curves during the test accomplishment. The test results indicated that natural ramie/bio-epoxy composite tube has the great potential to be used as an effective energy-absorbing device.  相似文献   
3.
The genetic expression of chimeric antigen receptors (CARs) on the surfaces of T cells enables the redirection of T cell specificity. To enhance the versatility of T cells as tumor-specific killers, we developed a nongenetic approach by which azide-containing sialic acids were metabolically incorporated into T cells to modify cellular sialyl glycans. After successful display of these moieties on the T cells, small-molecule ligands such as RGD and folate (as proof-of-concept, rather than supersized antibodies) were clicked orthogonally, leading to highly selective time- and dose-dependent cytotoxicity to integrin αvβ3- and folate-receptor-positive cells, respectively. This chemical approach provides a facile platform for rational design of tumor-specific cytotoxic T cells for targeted immunotherapy.  相似文献   
4.
The effect of codon context on amber codon‐guided incorporation of noncanonical amino acids (NAAs) has been previously examined by antibiotic selection. Here, we re‐explored this effect by screening a library in which three nucleotides upstream and downstream of the amber codon were randomised, and inserted within the lacZ‐α gene. Thousands of clones were obtained and distinguished by the depth of blue colour upon exposure to X‐gal. Large‐scale sequencing revealed remarkable preferences in nucleotides downstream of the amber codon, and moderate preferences for upstream nucleotides. Nucleotide preference was quantified by a dual‐luciferase assay, which verified that the optimum context for NAA incorporation, AATTAGACT, was applicable to different proteins. Our work provides a general guide for engineering amber codons into genes of interest in bacteria.  相似文献   
5.
Hitherto, no data describing the heterogeneity of genetic profiles and risk stratifications of adult acute myeloid leukaemia (AML) in Southeast Asia are reported. This study assessed genetic profiles, Moorman’s hierarchical classification, and ELN 2017-based risk stratifications in relation to age, gender, and ethnicity in Malaysian adult AML patients. A total of 854 AML patients: male (52%), female (48%) were recruited comprising three main ethnic groups: Malays (59%), Chinese (32%) and Indians (8%). Of 307 patients with abnormal karyotypes: 36% exhibited translocations; 10% deletions and 5% trisomies. The commonest genotype was FLT3-ITD-NPM1wt (276/414; 66.7%). ELN 2017 risk stratification was performed on 494 patients, and 41% were classified as favourable, 39% as intermediate and 20% as adverse groups. More females (47%) were in the favourable risk group compared to males (37%), whereas adverse risk was higher in patients above 60 (24%) of age compared to below 60 (18%) patients. We observed heterogeneity in the distribution of genetic profiles and risk stratifications between the age groups and gender, but not among the ethnic groups. Our study elucidated the diversity of adult AML genetic profiles between Southeast Asians and other regions worldwide.  相似文献   
6.
灰色关联分析法及其在膨胀土等级判定中的应用   总被引:3,自引:1,他引:2  
本文提出用灰色关联分析法和灰色权距分析法来判定膨胀土的胀缩等级.并与模糊判定法、灰色聚类法的计算结果进行对比.说明灰色关联法和灰色权距法应用效果较好。  相似文献   
7.
Image analysis is an interesting research area with a large variety of challenging applications. Researchers have worked from decades on this topic, as witnessed by the scientific literature. However, document image analysis is the special case in image analysis as their spatial properties are different from natural images. Therefore, the main focus of this paper is to describe image denoising issues in general and document image issues in particular. Since the field of document processing is relatively new, it is also dynamic, so current methods have room for improvement and innovations are still being made. Several algorithms proposed in the literature are described. Critical discussions are reported about the current status of the field and open problems are highlighted. It is also demonstrated that, there are rarely definitive techniques for all cases of a certain problem. We surveyed the state of art, analyzed recent trends and tried to identify challenges for future research in this field.  相似文献   
8.
In this paper, a method based on genetic algorithm is proposed for determining the optimum connection point with the highest lateral buckling load in the Off-Centre bracing system. This type of bracing system is mostly used in seismic areas and it allows architects to have more openings in the panel area. In this system, the non-straight diagonal member introduces eccentricity to the system and is connected to the corner of the frame by a third member. In designing this system, designers often use “trial and error” to locate the connection point of the brace elements considering various parameters affecting the design such as opening and frame dimensions, cross sectional areas of brace elements and the location of the brace element connection. Hence, finding the best connection point with maximum lateral buckling load can be problematic by the conventional methods. To demonstrate the effectiveness of the proposed GA method, examples with different frame specifications were presented.  相似文献   
9.
Moments have been used in all sorts of object classification systems based on image. There are lots of moments studied by many researchers in the area of object classification and one of the most preference moments is the Zernike moment. In this paper, the performance of object classification using the Zernike moment has been explored. The classifier based on neural networks has been used in this study. The results indicate the best performance in identifying the aggregate is at 91.4% with a ten orders of the Zernike moment. This encouraging result has shown that the Zernike moment is a suitable moment to be used as a feature of object classification systems.  相似文献   
10.
建筑工程抗震设防类别的判定是抗震设计的主要依据之一,决定着建筑工程抗震设防的水平高低。建筑工程抗震设防类别的划分主要根据建筑遭受地震损坏对各方面影响的后果的严重性进行综合分析确定。本文拟对建筑工程抗震设防类别判定中常见问题进行分析,结合工程实例,给出正确的判定方法,供参考。  相似文献   
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