Synthesis and Characterization of Palm Oil-Based Resin For UV Coating

The production of UV curable acrylated polyol esters fiom palm oil and its downstream products offers potential and promising materials for a number of applications such as polymeric film preparation and wood coatings. in this study, palm olein-based polyol of ethylene glycol was reacted with acrylic acid in the presence of a catalyst and inhibitors via condensation esterification process at various temperatures (70.0, 80.0, 90.0 or 100.O°C), stirring speed of 100 or 400 rpm and under vacuum for 15 hours. The reaction temperature of 80.0°C and the stirring rate of 400 rpm produce a homogeneous product. Optimizations for the synthesis were also carried out using a catalyst concentrations ranging fiom 0.0 to 5.0% of polyol weight.Fifteen different formulations have been investigated using the synthesized prepolymers with monomers and a small amount of photoinitiator. Monomers used were 1,6-hexanediol diarylate (HDDA) and trimethylolpropane triacrylate W T A ) while photoinitiator used was l-hydroxy cyclohexyl phenylketone (Irgacure 184). The mixtures were cured to make thin polymeric films under W radiation with doses between 2 to 14 passes (energy per pass is 0.600 ~lcm~C)o.a ting and curing was carried out on glass for pendulum hardness characterization, haziness and scratch measurement as well as FT-IR analysis. Coating and curing were done on rubber wood for cross hatch adhesion test. Pendulum hardness 'of the film prepared h m the UV curable formulation with monomer HDDA and the prepolymer prepared using 3% catalyst was 24.5%. The radiation dose was 14 passes. The highest pendulum hardness of 49.4% was achieved when using WV curable formulation with monomer TMPTA and the prepolymer prepared using 2% catalyst. The radiation dose needed was 10 passes. Formulation of UV curable coating using the optimized aaylated polyol ester prepolymer and monomer TMPTA exhibited higher scratch measurement and lower haziness compared to those of the formulation with monomer HDDA UV curable formulation of prepolymer with monomer HDDA gave better adhesion on rubber wood than that of with monomer TMPTA Films cured by W radiation made from prepolymexs on both $ass panel and rubber wood surfaces showed good hardness, scratch resistance and adhesion with almost clear transparency. In general, it can be conchided that newly synthesized UV radiation curable palm-based acrylated polyol ester prepotymers are promising candidates for wood coating applications

Synthesis and characterization of palm-based resin for UV coating

The production of UV curable acrylated polyol ester prepolymer from palm oil and its downstream products offer potential and promising materials for applications such as polymeric film preparation and coatings. In this study, palm olein polyol was reacted with acrylic acid in the presence of a catalyst and inhibitors via condensation esterification process. The reaction temperature of 80C and the stirring rate of 400 rpm produce a homogeneous product. Based on iodine value result, the suitable amount of p-toluene sulfonic acid monohydrate used as catalyst was 3.0% (w/w) of palm olein polyol. Different UV curable formulations have been investigated using the synthesized prepolymers with monomers and a small amount of photoinitiator. Monomers used were 1,6-hexanediol diacrylate (HDDA) and trimethylolpropane triacrylate(TMPTA) while photoinitiator used was 1-hydroxy cyclohexyl phenylketone (Irgacure 184). The mixtures were cured to make thin polymeric films under UV radiation with doses between 2 and 14 passes (energy per pass is 0.6 J/cm2). Coating and curing was carried out on glass for pendulum hardness and FTIR analysis. Pendulum hardness of the film prepared using monomer HDDA and the prepolymer previously synthesized using 3.0% catalyst was 24.5%. The radiation dose needed was 14 passes. The highest pendulum hardness of 49.4% was achieved using monomer TMPTA and the prepolymer synthesized using 2.0% catalyst. The radiation dose needed was 10 passes

Genomic Dissection of Bipolar Disorder and Schizophrenia, Including 28 Subphenotypes

publisher: Elsevier articletitle: Genomic Dissection of Bipolar Disorder and Schizophrenia, Including 28 Subphenotypes journaltitle: Cell articlelink: https://doi.org/10.1016/j.cell.2018.05.046 content_type: article copyright: © 2018 Elsevier Inc

Rave New World : partying with Singaporean youths, club drugs, and the rave culture : proposal for year 2001/2002 anti-club experimentation advertising campaign.

The study documents and analyses the shifting developments in contemporary drug use in Singapore. We will be focusing on club drugs and the emerging rave culture to examine how it affects youths (aged between 18-29 years old). Five types of club drugs will be highlighted-Ecstasy Ketamine, Ice, Speed and Yaba.Bachelor of Communication Studie

Viral and Antibody Kinetics, and Mosquito Infectivity of an Imported Case of Zika Fever Due to Asian Genotype (American Strain) in Singapore

We report a case of a Singaporean who acquired Zika virus (ZIKV) during a visit to Cuba. The infection was confirmed using molecular and serological methods. This report highlights potential drawbacks of using IgG serology for diagnosis of flavivirus infections in endemic regions. The low viremia detected during the early phase of this case resulted in low mosquito infectivity rates, suggesting the possibility of ZIKV transmission prior to clinical onset. The report also emphasizes the challenges of public health interventions for Zika fever and the importance of sustaining a low vector population to reduce the risk of arbovirus transmission in vulnerable regions

The 4717C > G polymorphism in periplakin modulates sensitivity to EGFR inhibitors

Abstract The use of EGFR inhibitors on oral squamous cell carcinoma (OSCC) as monotherapy yielded modest clinical outcomes and therefore would benefit from biomarkers that could predict which patient subsets are likely to respond. Here, we determined the efficacy of erlotinib in OSCC cell lines, and by comparing sensitive and resistant lines to identify potential biomarkers. We focused on the 4717C > G polymorphism in periplakin (PPL) where the CC genotype was associated with erlotinib resistance. To validate this, erlotinib-resistant cell lines harbouring CC genotype were engineered to overexpress the GG genotype and vice versa. Isogenic cell lines were then studied for their response to erlotinib treatment. We demonstrated that overexpression of the GG genotype in erlotinib-resistant lines sensitized them to erlotinib and inhibition of AKT phosphorylation. Similarly, the expression of the CC genotype conferred resistance to erlotinib with a concomitant increase in AKT phosphorylation. We also demonstrated that cell lines with the CC genotype generally are more resistant to other EGFR inhibitors than those with the GG genotype. Overall, we showed that a specific polymorphism in the PPL gene could confer resistance to erlotinib and other EGFR inhibitors and further work to evaluate these as biomarkers of response is warranted

One-Carbon Metabolism Biomarkers and Risks of Incident Neurocognitive Disorder among Cognitively Normal Older Adults

There is a lack of evidence supporting an association between folate and vitamin B12 exposure with cognitive outcomes. We examined serum folate and vitamin B12 and plasma homocysteine in 690 cognitively-normal adults (aged ≥ 55) from the Singapore Longitudinal Aging Study (SLAS-2) followed-up over 4.5 years on incident neurocognitive disorder (NCD): mild cognitive impairment (MCI) and dementia. At follow-up, 5.7% (39) of participants developed NCD (34 MCI and 5 dementia). Comparing with those who remained cognitively-normal, participants progressed to NCD had significantly lower mean baseline vitamin B12 (420 [SD ± 221] vs. 510 [SD ± 290] pmol/L, p = 0.026), higher homocysteine (14.6 [SD ± 4.2] vs. 12.9 [SD ± 4.3], p = 0.018) and lower one-carbon index (Z-scores: −0.444 [SD ± 0.819] vs. −0.001 [SD ± 0.990], p = 0.006). Adjusted for confounders, significant associations with incident NCD were found for lower vitamin B12 (per-SD OR = 2.10, 95%CI = 1.26–3.52), higher homocysteine (per-SD OR = 1.96, 95%CI = 1.18–3.24) and lower one-carbon index (per-SD OR = 1.67, 95%CI = 1.06–2.64). Folate was not significantly associated with progression to NCD. Notably, low B12 in the presence of high folate was significantly associated with incident NCD (adjusted OR = 3.81, 95%CI = 1.04–13.9). Low B12, high homocysteine, low B12 in the presence of high folate, and a one-carbon index of hypo-methylation were independently associated with progression to NCD among cognitively normal