ABSTRACT:The technical viability of using rice husk ashes (RHA) as alternative fillers in polypropylene was studied. Three types of RHA, white rice husk ash (WRHA), black rice husk ash (BRHA) and amorphous rice husk ash (AMRHA) at 10-40wt% filler loading were investigated. The RHA composites were compounded by twin screw compounders and the mechanical properties of the composites evaluated. Incorporation of the RHA fillers increased the flexural modulus of the composites, particularly the BRHA composities. Modulus of the RHA composites were found to be in good agreement with theoretical values predicted by equation of Lewis and Nielsen. The increase in modulus was offset by lowering of the tensile strength, elongation at break and impact properties. Theoretical treatments of the ultimate tensile strength performed based on the model proposed by Nicolai and Nicodemo showed reasonably good agreement. The mechanical properties of the RHA composites were of comparable values with the prepared polypropylene composites filled with commercial Neu burg silica. Transformation of the crystalline RHA to amorphous RHA resulted in composites with improved tensile strength. No coupling agent was used in this study.KEY WORDS Rice Husk Ash / Filler / Polypropylene / Composites / Mechanical Properties/ Incorporation of fillers into a polymer is known to cause substantial changes to the mechanical properties of the composities. As polymer composites are increasingly used in various mechanical applications, the mechanical properties are perhaps the most basic and important behaviors that need to be investigated in order to evaluate the performance of the composities when they are subjected to stress.term of modulus of elasticity, ultimate tensile strength, impact resistance, etc. The term mechanical is applied for this category of properties because they are often used to indicate the suitability of a material for use in mechanical applications, parts that carry a !oak, absorb shock, etc. 1 The principal objective of this study is to investigate the technical viability of using the rice husk ashes which are usually regarded as waste products as alternative low cost fillers in polypropylene. In this investigation, the mechanical properties of the polypropylene/ rice hush ash (RHA) composites are investigated in term of their modulus, tensile and impact properties. Modulus is a measure of The basic characterization of the mechanical properties are usually determined by tests resulting in various deformation versus stress dependencies, for instance the stressstrain diagrams. Examinations of such dependencies yield mechanical characteristics in * To whom correspondence should be addressed. 1002Mechanical Properties of RHA/PP Composites the stiffness of a material subjected to shear loading. Addition of filler normally improves the stiffness of the composities. Tensile test is among the most widely employed test method to characterize the mechanical properties of composites. From such a test, enomorous amount of important information m...

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Herpes simplex virus type-1 (HSV-1) encephalitis (HSE) is the most commonly diagnosed cause of viral encephalitis in western countries. Despite antiviral treatment, HSE remains a devastating disease with high morbidity and mortality. Improved understanding of pathogenesis may lead to more effective therapies. Mitochondrial damage has been reported during HSV infection in vitro. However, whether it occurs in the human brain and whether this contributes to the pathogenesis has not been fully explored. Minocycline, an antibiotic, has been reported to protect mitochondria and limit brain damage. Minocycline has not been studied in HSV infection. In the first genome-wide transcriptomic study of post-mortem human HSE brain tissue, we demonstrated a highly preferential reduction in mitochondrial genome (MtDNA) encoded transcripts in HSE cases (n = 3) compared to controls (n = 5). Brain tissue exhibited a significant inverse correlation for immunostaining between cytochrome c oxidase subunit 1 (CO1), a MtDNA encoded enzyme subunit, and HSV-1; with lower abundance for mitochondrial protein in regions where HSV-1 was abundant. Preferential loss of mitochondrial function, among MtDNA encoded components, was confirmed using an in vitro primary human astrocyte HSV-1 infection model. Dysfunction of cytochrome c oxidase (CO), a mitochondrial enzyme composed predominantly of MtDNA encoded subunits, preceded that of succinate dehydrogenase (composed entirely of nuclear encoded subunits). Minocycline treated astrocytes exhibited higher CO1 transcript abundance, sustained CO activity and cell viability compared to non-treated astrocytes. Based on observations from HSE patient tissue, this study highlights mitochondrial damage as a critical and early event during HSV-1 infection. We demonstrate minocycline preserves mitochondrial function and cell viability during HSV-1 infection. Minocycline, and mitochondrial protection, offers a novel adjunctive therapeutic approach for limiting brain cell damage and potentially improving outcome among HSE patients.Electronic supplementary materialThe online version of this article (doi:10.1007/s00401-016-1597-2) contains supplementary material, which is available to authorized users.

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Evidence of gut microbiota involvement in regulating glucose metabolism and type 2 diabetes mellitus (T2DM) progression is accumulating. The understanding of microbial dysbiosis and specific alterations of gut microbiota composition that occur during the early stages of glucose intolerance, unperturbed by anti-diabetic medications, is especially essential. Hence, this systematic review was conducted to summarise the existing evidence related to microbiota composition and diversity in individuals with prediabetes (preDM) and individuals newly diagnosed with T2DM (newDM) in comparison to individuals with normal glucose tolerance (nonDM). A systematic search of the PubMed, MEDLINE and CINAHL databases were conducted from inception to February 2021 supplemented with manual searches of the list of references. The primary keywords of “type 2 diabetes”, “prediabetes”, “newly-diagnosed” and “gut microbiota” were used. Observational studies that conducted analysis of the gut microbiota of respondents with preDM and newDM were included. The quality of the studies was assessed using the modified Newcastle-Ottawa scale by independent reviewers. A total of 18 studies (5,489 participants) were included. Low gut microbial diversity was generally observed in preDM and newDM when compared to nonDM. Differences in gut microbiota composition between the disease groups and nonDM were inconsistent across the included studies. Four out of the 18 studies found increased abundance of phylum Firmicutes along with decreased abundance of Bacteroidetes in newDM. At the genus/species levels, decreased abundance of Faecalibacterium prausnitzii, Roseburia, Dialister, Flavonifractor, Alistipes, Haemophilus and Akkermansia muciniphila and increased abundance of Lactobacillus, Streptococcus, Escherichia, Veillonella and Collinsella were observed in the disease groups in at least two studies. Lactobacillus was also found to positively correlate with fasting plasma glucose (FPG), HbA1c and/or homeostatic assessment of insulin resistance (HOMA-IR) in four studies. This renders a need for further investigations on the species/strain-specific role of endogenously present Lactobacillus in glucose regulation mechanism and T2DM disease progression. Differences in dietary intake caused significant variation in specific bacterial abundances. More studies are needed to establish more consistent associations, between clinical biomarkers or dietary intake and specific gut bacterial composition in prediabetes and early T2DM.

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In the composite industry, natural fibres have great potential to replace synthetic fibres like carbon and glass, due to their low cost and environmentally friendly materials. Bamboo is emerging as a versatile reinforcing fibre candidate because this woody plant has a number of advantages, such as being naturally strong, biodegradable and abundantly available. In this study, a compression test with a crosshead displacement rate of 1 mm/min was conducted on square and triangular honeycomb core structures based on bamboo-epoxy composites so as to study their specific energy absorption. Both square and triangular honeycomb structures were manufactured by the slotting technique. Initially, a tensile test with the same crosshead displacement rate was conducted to study the tensile strength of unidirectional bamboo-epoxy composites with 0°, 45° and 90° fibre orientations. Bamboo-epoxy composite laminates were fabricated by applying a hand lay-up technique. The experimental data showed that the unidirectional bamboo-epoxy composite with 0° orientation offered the highest tensile strength. This indicates that the bamboo is stronger when parallel to the tensile axis. Meanwhile, the triangular honeycomb bamboo-epoxy structure offered about 10% more energy absorption than the square honeycomb structure, which indicates that the smaller cell size of honeycomb is able to absorb more energy than the bigger one.