Synthesis and characterization of Cu(II), Ni(II) and Zn(II) metal complexes of bidentate NS isomeric Schiff bases derived from S-methyldithiocarbazate (SMDTC): Bioactivity of the bidentate NS isomeric Schiff bases, some of their Cu(II), Ni(II) and Zn(II) complexes and the X-ray structure of the bis[S-methyl-β-N-(2-furyl-methyl)methylenedithiocarbazato]zinc(II) complex.

Two new isomeric Schiff bases, S-methyl-β-N-(2-furylmethyl)methylenedithiocarbazate (NS′) and S-methyl-β-N-(5-methyl-2-furyl)methylenedithiocarbazate (NS″) have been prepared. Bis-chelated complexes of these two bidentate ligands, [M(NS)2], [M=Cu(II), Ni(II) and Zn(II)], were synthesized. The Schiff bases and their metal complexes have been characterized by a variety of physico-chemical techniques. X-ray crystallographic analysis shows that the Zn(II) complex, [Zn(NS′)2], is four-coordinate and has a distorted tetrahedral structure with the ligand coordinated to the Zn(II) ion as an uninegatively charged bidentate chelating agent via the azomethine nitrogen and the mercaptide sulfur atoms. The Cu(II) complexes are paramagnetic with a square-planar stereochemistry. The Ni(II) and [Zn(NS″)2] complexes have a square-planar and tetrahedral structure, respectively, however, they are diamagnetic. Only Cu(NS′)2 showed clear activity against the bacteria, Subtilis mutant (B28), while both NS′ and NS″ Schiff bases were strongly antifungal against Saccharomyces cereviceae (20341), Candida albicans, Candida lypolytica (2075) and Aspergillus ochraceous (398). Cu(NS′)2 and Ni(NS′)2 showed clear inhibition of C. albicans and S. cereviceae (20341), respectively. The Cu(NS′)2, Ni(NS′)2 and Zn(NS′)2 complexes showed very good activity against human cell T-lymphoblastic leukemia [CEM-SS] cells with CD50 values of 1.6, 2.1 and 3.0 μg ml−1, respectively. The remainder of the Schiff bases and complexes were inactive towards CEM-SS cells. None of the compounds showed any activity towards colon cancer cells (HT-29). Only the Cu(NS′)2 and Zn(NS′)2 complexes were highly active against cervical cancer cells (HELA cells) with CD50 values of 1.5 and 2.1 μg ml−1, while the Ni(NS′)2 complex was weakly active towards HELA cells with a CD50 value of 23.0 μg ml−1

Molecular analysis of CHX10 and MFRP in Chinese subjects with primary angle closure glaucoma and short axial length eyes

Molecular Vision141313-131

A common variant near TGFBR3 is associated with primary open angle glaucoma

Primary open angle glaucoma (POAG), a major cause of blindness worldwide, is a complex disease with a significant genetic contribution. We performed Exome Array (Illumina) analysis on 3504 POAG cases and 9746 controls with replication of the most significant findings in 9173 POAG cases and 26 780 controls across 18 collections of Asian, African and European descent. Apart from confirming strong evidence of association at CDKN2B-AS1 (rs2157719 [G], odds ratio [OR] = 0.71, P = 2.81 × 10−33), we observed one SNP showing significant association to POAG (CDC7–TGFBR3 rs1192415, ORG-allele = 1.13, Pmeta = 1.60 × 10−8). This particular SNP has previously been shown to be strongly associated with optic disc area and vertical cup-to-disc ratio, which are regarded as glaucoma-related quantitative traits. Our study now extends this by directly implicating it in POAG disease pathogenesis

Big data analysis of Terror Management Theory's predictions in the COVID-19 pandemic

The current study aimed to address the limitations of the terror management theory literature by using big data analysis to examine the theory’s predictions in the COVID-19 pandemic. Specifically, Google Trends were examined before and after the first COVID-19 case was identified in Singapore. The results showed that there was a significant increase in mortality salience, intergroup conflict, and prosocial behavior, and a significant decrease in materialism after the first COVID-19 case was identified. However, no significant differences were found for anxiety. Limitations include the assumption that search terms reflect intentions that would eventually lead to a relevant behavior and the lack of data from other sources to corroborate with the results from Google Trends. Future research could use data from other sources to examine the effects of COVID-19 on theoretically relevant behaviors

Immune response in infants after universal hepatitis B vaccination: a community-based study in MalaysIa

INTRODUCTION This study aimed to assess the immune response in infants who received the three-shot hepatitis B vaccine in Malaysia. METHODS Consecutive infants born between March 2002 and April 2010 who received three doses of hepatitis B vaccine at a community clinic in Malaysia were enrolled in the study. Screening for hepatitis B surface antigen (HBsAg) and antibody against HBsAg (anti-HBs) was performed after the completion of primary immunisation, at approximately one year of age. RESULTS A total of 572 infants (median age 9.3 +/- 2.7 months; range 6.3-48 months) were screened for immune response to hepatitis B vaccination - 553 (96.7) infants had adequate levels of anti-HBs (>= 10 IU/L). Of the 440 mothers whose HBsAg status was known, 14 (3.2) were positive for HBsAg. None of the 14 infants who were born to HBsAg-positive mothers were positive for HBsAg, and all but one infant had anti-HBs level >= 10 IU/L. Gender, gestational age and maternal HBsAg status were not found to significantly affect the subsequent immune response in infants following vaccination. CONCLUSION The proportion of Malaysian mothers who are positive for HBsAg remains high. The three-shot hepatitis B vaccine, given as part of universal vaccination against hepatitis B, provides adequate anti-HBs in the vast majority of infants in a community setting in Malaysia

Heat transfer performance of water-based tetrahydrofurfuryl polyethylene glycol-treated graphene nanoplatelet nanofluids

In order to improve the colloidal stability of graphene nanoplatelets (GNPs) in aqueous media, GNPs were first functionalized with tetrahydrofurfuryl polyethylene glycol in a quick electrophilic addition reaction method. To assess this, surface functionalization of the GNPs was analyzed by FTIR and Raman spectroscopy, and thermogravimetric analysis. In addition, the morphology of treated samples was investigated by transmission electron microscopy (TEM). As the second phase of the study, the thermophysical properties of samples were experimentally investigated. The third phase of the study involved experimentally measuring and numerically simulating the convective heat transfer coefficient and pressure drop of water-based TFPEG-treated GNP nanofluids (TGNP/water) at various weight concentrations and comparison with the base fluid in an annular heat exchanger. The results suggest that the addition of TGNP into the water improved the convective heat transfer coefficient dramatically. The pressure drop of prepared samples illustrated an insignificant variation as compared with the base fluid. The steady-state forced convective heat transfer experiments and simulation have confirmed the promising cooling capabilities of TGNP/water

Integrated soil investigation works off marina east, Singapore

14th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering

Thin nanostructured LiMn2O4 films by flame spray deposition and in situ annealing method

A new approach has been developed to rapidly synthesize nanostructured LiMn2O4 thin films by flame spray deposition (FSD) and in situ annealing. A precursor solution of lithium acetylacetonate and manganese acetylacetonate in an organic solution was supplied through a flame spray pyrolysis (FSP) reactor. The liquid solution spray was ignited and stabilized by a premixed methane/oxygen flame ring surrounding the FSP nozzle. Thus, LiMn2O4 nanoparticles were formed by combustion and deposited onto a current collector followed by in situ annealing. Two different types of current collectors, i.e. stainless steel and aluminum coated with carbon-based primer were tested. The prepared thin films were characterized by X-ray diffraction and field-emission scanning electron microscopy. The electrochemical properties of the thin films were evaluated by cyclic voltammetry and galvanostatic cycling. The LiMn2O4 films exhibited good cyclability. Films that underwent sintering and crystal growth during in situ annealing developed more robust film structures on the current collector surface and exhibited better electrochemical performance than poorly adhered films