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Modifications of mRNA, especially methylation of adenosine, have recently drawn much attention. The much rarer modification, 5-hydroxymethylation of cytosine (5hmC), is not well understood and is the subject of this study. Vertebrate Tet proteins are 5-methylcytosine (5mC) hydroxylases enzymes catalyzing the transition of 5mC to 5hmC in DNA and have recently been shown to have the same function in messenger RNAs in both vertebrates and in Drosophila. The Tet gene is essential in Drosophila because Tet knock-out animals do not reach adulthood. We describe the identification of Tet-target genes in the embryo and larval brain by determining Tet DNA-binding sites throughout the genome and by mapping the Tet-dependent 5hmrC modifications transcriptome-wide. 5hmrC-modified sites can be found along the entire transcript and are preferentially located at the promoter where they overlap with histone H3K4me3 peaks. The identified mRNAs are frequently involved in neuron and axon development and Tet knock-out led to a reduction of 5hmrC marks on specific mRNAs. Among the Tet-target genes were the robo2 receptor and its slit ligand that function in axon guidance in Drosophila and in vertebrates. Tet knock-out embryos show overlapping phenotypes with robo2 and are sensitized to reduced levels of slit . Both Robo2 and Slit protein levels were markedly reduced in Tet KO larval brains. Our results establish a role for Tet-dependent 5hmrC in facilitating the translation of modified mRNAs, primarily in developing nerve cells.

In this study, the effectiveness of mango polyphenol (MPP) powder in seawater pH 7.4 as a natural treatment on the mechanical properties of unidirectional full culm bamboo (Dendrocalamus asper) was investigated. Our observations are explained through the changes in MPP percentage of 5, 10, and 20 of the raw material upon treatment, where the 10% amount of MPP are dominant in compressive strength with 43.83 MPa at the top part (nodal), 10% amount of MPP in compressive strength with 47.13 MPa at the middle part (non-nodal), and 5% in flexural strength with 43.07 MPa at the top part. The treatment process combining sea-water absorption plus mango polyphenol powder is more effective in improving mechanical properties with MPP variations than using them alone. Finally, materials identified as having favorable effects on full bamboo culm.

Synthesis of ceramic nanofibers is commonly carried out through electrospinning method. However, with the emergence of solution blow spinning (SBS) technology, spinning of nanofiber and its composites has resulted in a more straightforward and commercially scalable process. In this study, ceramic nanofibers (i.e., TiO2 nanofibers) were synthesized through SBS followed by calcination. Three critical parameters were investigated (i.e., precursor concentration, calcination temperature and time) to produce ready-to-use composite membranes and pure ceramic nanofibers. Characterizations of ceramic membranes and pure nanofibers include scanning electron microscope (SEM) analysis and energy dispersive x-ray (EDX) for elemental component analysis. Insights on the transformation of composite membranes into pure ceramic nanofibers and the role of calcination are also discussed.

Mango seed kernel (MSK) is a waste material of the mango processing industry and is reported to significantly contain phenolic compounds with anti-oxidative properties. In this work, these compounds are isolated via solid-liquid extraction (SLE) in which solvent mixture design approach was used to evaluate the optimal quaternary solvent ratio in relation to the phenolics content of extracts from MSK. The quaternary solvent is composed of ethanol (E), methanol (M), acetone (A), and water (W). The extraction process was implemented at 40°C for 60 minutes with the ratio between solid and solvent at 1:25. Response surface methodology coupled with simplex lattice design was developed to evaluate the optimal solvent system and their interaction effects on the phenolic compounds content. The linear, two-way, and three-way interaction, except for methanol-acetonewater system, resulted in positive effects on the phenolic compounds content. The response model shows that a quaternary mixture with approximately 3:3:3:1 E:M:A:W ratio provided the highest phenolic content. A Scheffé cubic model sufficiently described the extraction process. The results of this study showed that the extraction of phenolic compounds in MSK via SLE using a mixture of solvents is possible. Higher extraction efficiencies can be achieved by optimizing the SLE process, and the optimum conditions can be applied to produce phenolic extracts with positive antioxidant activity.

Cellulose-based nanofiber membrane fabrication remains a global challenge, especially the use of alternative and sustainable sources of cellulosic materials. Herein, an easy and highly scalable cellulose-based nanofiber membrane was successfully fabricated using a solution blow spinning (SBS) method. Such membrane fabrication was carried out with the assistance of an easy-to-spin precursor polymer (i.e. polyacrylonitrile (PAN)). Through this strategy, cellulose acetate (CA) was successfully spun into a ready-to-use membrane. The formation of CA with the PAN nanofiber is concentration-dependent and requires high air pressure to effectively overcome the composite precursor's surface tension and eventually produce nanofibers. Favourable CA concentration in PAN (i.e. 50%-65% v/v CAN/PAN) is important to the formation of sufficient molecular entanglement with PAN in solution. Upon fulfilling the optimized CA concentration, high air pressure (i.e. ≥3 bars) is used to produce jet-like polymeric fibers of PAN dragging off CA, forming numerous nanofibers which are then collected into a substrate forming a membrane. Characterizations of the CA/PAN composite nanofiber were carried out using scanning electron microscopy, Fourier transform infrared, thermogravimetric analysis and differential scanning calorimetry (DSC). Such unique composite nanofiber membranes have potential as filters and adsorbent membranes for air and water/wastewater applications, as well as for biorefinery applications.