Thermal behaviour of single ply triaxial woven fabric composites

This paper studies the complex thermal deformation of single-ply triaxial weave com- posites. This behaviour is studied experimentally, by testing ?at plates and narrow strips of TWF, and numerically, by carrying out ?nite-element simulations that capture the e?ects of the thermo-mechanical anisotropy of the individual tows that make up the composite. It is shown that the dominating e?ect is the development of a thermally-induced twist

Physical, thermal, and mechanical properties of polypropylene composites filled with rattan nanoparticles

Natural fillers are recognized as the materials that feature a poor fiber/matrix interaction. As a result, their composites behaviors are directly compromised. Existing evidence has exhibited that nanoparticle fillers can be employed as an alternative size to overcome this problem. We thus examined in this study the effects of rattan filler of nanoparticle size on the physical, thermal, and mechanical properties of the composite. Neat polypropylene (PP), PP with 5% rattan nanoparticle (PP/R5), and PP with 5% glass fiber (PP/FG5) were considered. For performance assessment, particle size analysis, morphology, X-ray diffraction, thermal inspection, and mechanical tests were carried out. The highest degree of crystallinity was discovered in PP/R5. Tensile properties of both PP/FG5 and PP/R5 were comparable although the former demonstrated higher moduli of elasticity and rupture. Well-distributed constituents were displayed in PP/R5 by means of morphological study, which offered insight into its highest average hardness, maximum strain, and therefore its advantageous ductile behavior compared to the other considered materials

Hematopoiesis and T-cell specification as a model developmental system

The pathway to generate T cells from hematopoietic stem cells guides progenitors through a succession of fate choices while balancing differentiation progression against proliferation, stage to stage. Many elements of the regulatory system that controls this process are known, but the requirement for multiple, functionally distinct transcription factors needs clarification in terms of gene network architecture. Here, we compare the features of the T-cell specification system with the rule sets underlying two other influential types of gene network models: first, the combinatorial, hierarchical regulatory systems that generate the orderly, synchronized increases in complexity in most invertebrate embryos; second, the dueling ‘master regulator’ systems that are commonly used to explain bistability in microbial systems and in many fate choices in terminal differentiation. The T-cell specification process shares certain features with each of these prevalent models but differs from both of them in central respects. The T-cell system is highly combinatorial but also highly dose-sensitive in its use of crucial regulatory factors. The roles of these factors are not always T-lineage-specific, but they balance and modulate each other's activities long before any mutually exclusive silencing occurs. T-cell specification may provide a new hybrid model for gene networks in vertebrate developmental systems

Transverse slab reinforcement design of concrete bridge deck: A review

This paper reviews the current design practices of transverse slab reinforcement design in concrete bridge deck, which consist of concrete deck slab on wide concrete T-beams. The conventional bridge design method results in the provision of excessive transverse steel reinforcement in the concrete bridge deck slab due to the fact that, the slab is assumed to bear the applied vehicular loadings alone without considering the contribution of the wide T-beam flanges. Thus, the design which is based on bending and failure proved to be too conservative. Through critical review, issues regarding some design approaches were discussed. It has been found that, designing the deck slab in transverse direction would enable the vehicle wheel loads to be supported by the wide T- beam flanges and performance enhancement can be achieved by compressive membrane action resulted from the natural stiffness of the wide girder flanges. The presence of this membrane forces provides a punching shear capacity, which is far beyond the flexural design capacity for the new bridge deck system. This capacity would result in substantial reduction of the transverse reinforcement within the slab

Rapid actin monomer–insensitive depolymerization of Listeria actin comet tails by cofilin, coronin, and Aip1

Actin filaments in cells depolymerize rapidly despite the presence of high concentrations of polymerizable G actin. Cofilin is recognized as a key regulator that promotes actin depolymerization. In this study, we show that although pure cofilin can disassemble Listeria monocytogenes actin comet tails, it cannot efficiently disassemble comet tails in the presence of polymerizable actin. Thymus extracts also rapidly disassemble comet tails, and this reaction is more efficient than pure cofilin when normalized to cofilin concentration. By biochemical fractionation, we identify Aip1 and coronin as two proteins present in thymus extract that facilitate the cofilin-mediated disassembly of Listeria comet tails. Together, coronin and Aip1 lower the amount of cofilin required to disassemble the comet tail and permit even low concentrations of cofilin to depolymerize actin in the presence of polymerizable G actin. The cooperative activities of cofilin, coronin, and Aip1 should provide a biochemical basis for understanding how actin filaments can grow in some places in the cell while shrinking in others

Cryptosporidium in fish: alternative sequencing approaches and analyses at multiple loci to resolve mixed infections

Currently, the systematics, biology and epidemiology of piscine Cryptosporidium species are poorly understood. Here, we compared Sanger ‒ and next-generation ‒ sequencing (NGS), of piscine Cryptosporidium, at the 18S rRNA and actin genes. The hosts comprised 11 ornamental fish species, spanning four orders and eight families. The objectives were: to (i) confirm the rich genetic diversity of the parasite and the high frequency of mixed infections; and (ii) explore the potential of NGS in the presence of complex genetic mixtures. By Sanger sequencing, four main genotypes were obtained at the actin locus, while for the 18S locus, seven genotypes were identified. At both loci, NGS revealed frequent mixed infections, consisting of one highly dominant variant plus substantially rarer genotypes. Both sequencing methods detected novel Cryptosporidium genotypes at both loci, including a novel and highly abundant actin genotype that was identified by both Sanger sequencing and NGS. Importantly, this genotype accounted for 68·9% of all NGS reads from all samples (249 585/362 372). The present study confirms that aquarium fish can harbour a large and unexplored Cryptosporidium genetic diversity. Although commonly used in molecular parasitology studies, nested PCR prevents quantitative comparisons and thwarts the advantages of NGS, when this latter approach is used to investigate multiple infections

Renminbi Internationalisation: Precedents and Implications

While it is commonly assumed that there are no known precedents against which to benchmark the internationalisation of the Renminbi (RMB), this paper argues that the PRCs own development experience provides a useful perspective on the internationalisation debate. In particular it indicates that lessons can be learnt from both the successes and the shortcomings of efforts to internationalise the RMB in the 1970s. During this period state-owned banks in Hong Kong played a central role in mobilising finance for foreign trade. Access to Hong Kong’s developed financial institutions allowed the PRC to maximise receipts from foreign trade as well as minimise the risks of undue swings in capital flows. The paper shows that although China no longer faces foreign exchange scarcity, economic reforms have not yet resolved vulnerabilities in China’s financial institutions and as such Hong Kong’s role in mitigating the risk of undue capital swings remains

A survey of Edwardsiella ictaluri in wild catfish populations in Australia

This report contains the findings of the first survey of the exotic bacterium Edwardsiella ictaluri in wild freshwater fish populations in Australia. Edwardsiella ictaluri causes enteric septicaemia of catfish (ESC), which is a serious disease of farmed channel catfish in the USA. The bacterium has previously been detected in imported ornamental fish and in native catfish held in Australian aquarium facilities, but wild fish populations in Australia are considered free of the disease. The Australian Government Department of Agriculture, through the Fisheries Research and Development Corporation, funded an active surveillance program to provide further evidence for this claim of disease freedom

Understanding the Relationship between Sport Courage and Female Soccer Performance Variables

The purpose of this study was to examine the relationships between female soccer players' courage and key performance variables (level of participation, injury past, being selected or non-selected by a national team, being starter or substitute). METHODS: The Sport Courage Scale-31, by Konter and Ng (2012) and key performance variables were collected from 210 female soccer players aged 12 to 27 (M = 17.97 ± 3.34 years old). Spearman correlations and Mann-Whitney U tests were used to analyse the collected data. RESULTS: The correlations between mastery (r = 0.196), determination (p = 0.239), assertiveness (r = 0.325), sacrifice behaviour (r = 0.182), total sport courage (r = 0.265) and age of female soccer players were found to be significant (p < 0.05). Female soccer players who have sustained an injury in the past scored significantly higher on the venturesome scale (p = 0.006) than those who have not sustained an injury in the past. In comparison, female soccer players who have not sustained an injury in the past or who have not been substituted had significantly more mastery than female soccer players who have sustained an injury in the past or who have been substituted (p = 0.017, p = 0.002, respectively). CONCLUSIONS: This study indicates that sport courage is related to key performance variables among female soccer players. Mastery and age seem to be related to courageous behaviour, whereas increasing venturesomeness might cause injuries in female soccer. Some relevant implications for practitioners can be drawn from the present findings

Malay Version of Exercise Self-Efficacy: A Confirmatory Analysis among Malaysians with Type 2 Diabetes Mellitus

© 2020 by the authors. Exercise self-efficacy (ESE) is one of the psychological constructs in the Transtheoretical Model (TTM). The objective of the present study is to assess the validity and reliability of the Malay version of Exercise self-efficacy scale (ESE-M) among Malaysians with type 2 diabetes mellitus (T2DM). A cross-sectional study design with convenience sampling method using a self-administered questionnaire was carried out. Participants were invited to complete the ESE-M with 18 items. Confirmatory factor analysis (CFA) was conducted and composite reliability (CR) was computed using Mplus 8. A total of 331 Malaysians with T2DM with a mean age of 63 years old (Standard Deviation = 0.57) completed the questionnaire. Most of the participants were male (52%) and Malay (89.4%). Two initial CFA models (single factor and three factors) of ESE-M scale were tested and they did not fit to the data well. Several re-specifications of the models were conducted. The final model for the ESE-M showed improvement on the value of model fit indices for the single factor model (comparative fit index (CFI) = 0.952, Tucker and Lewis index (TLI) = 0.938, standardised root mean square (SRMR) = 0.044, root mean square error of approximation (RMSEA) = 0.054) and three factors model (CFI = 0.891, TLI = 0.863, SRMR = 0.049, RMSEA = 0.081). The CR for the self-efficacy factor was 0.921 (single factor), while CR for internal feelings, competing demands and situational (three factors) were 0.762, 0.818 and 0.864, respectively. The final model of single factor ESE-M showed better fit to the data compared to the three factors ESE-M. This indicated that the single factor ESE-M is more suitable to be adopted for future study among Malaysians with T2DM.Exercise Medicine Research Grant (EMRG/2019/19004)