Non-invasive health prediction from visually observable features [version 2; peer review: 1 approved, 1 approved with reservations]

Background: The unprecedented development of Artificial Intelligence has revolutionised the healthcare industry. In the next generation of healthcare systems, self-diagnosis will be pivotal to personalised healthcare services. During the COVID-19 pandemic, new screening and diagnostic approaches like mobile health are well-positioned to reduce disease spread and overcome geographical barriers. This paper presents a non-invasive screening approach to predict the health of a person from visually observable features using machine learning techniques. Images like face and skin surface of the patients are acquired using camera or mobile devices and analysed to derive clinical reasoning and prediction of the person’s health. Methods: In specific, a two-level classification approach is presented. The proposed hierarchical model chooses a class by training a binary classifier at the node of the hierarchy. Prediction is then made using a set of class-specific reduced feature set. Results: Testing accuracies of 86.87% and 76.84% are reported for the first and second-level classification. Empirical results demonstrate that the proposed approach yields favourable prediction results while greatly reduces the computational time. Conclusions: The study suggests that it is possible to predict the health condition of a person based on his/her face appearance using cost-effective machine learning approaches

Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts

Characterization of sortase a expression in enterococcus faecalis.

Gram-positive bacteria rely on a family of sorting enzymes called sortases to attach cell surface proteins, often virulence factors, to their peptidoglycan cell wall. Two classes of sortase enzyme exist in Enterococcus faecalis, sortase A (SrtA) and sortase C (SrtC). Understanding these enzymes will provide new insight on sortases as a new target for antimicrobial therapy. This study aims to characterize SrtA, a key contributor to the pathogenicity of E. faecalis. Immunofluorescence microscopy and immunoblotting techniques were employed to determine the expression and localization pattern of SrtA. SrtA was observed on approximately 20% of cells in the planktonic mode of life with specific localization in foci at the division septum. Interestingly, when grown to form biofilms, SrtA was found to be expressed in most, if not all cells. Furthermore, instead of localizing at single foci at the septum, SrtA was distributed at the hemisphere of the biofilm cells, a phenotype completely different as opposed to planktonic cells. We conclude that SrtA expression is highly variable in different modes of life and growth phases.Bachelor of Science in Biological Science

Spatial and temporal localization of cell wall associated pili in Enterococcus Faecalis

Enterococcus faecalis relies upon a number of cell wall-associated proteins for virulence. One sortase-assembled virulence factor is the endocarditis and biofilm associated pilus (Ebp), an important factor for biofilm formation. The current paradigm for virulence factor assembly in Gram-positive bacteria is that Sortase A recognizes and cleaves at the LPXTG motif within its substrates and covalently attaches them to the growing cell wall at sites of new cell wall synthesis. While the cell wall anchoring mechanism and polymerization of Ebp is well characterized, less is known about the spatial and temporal deposition of this protein on the cell surface. We followed the distribution of Ebp and peptidoglycan (PG) at different growth stages of E. faecalis via immunofluorescence, along with fluorescent D-amino acids (FDAA) staining. Surprisingly, cell surface Ebp did not co-localize with newly synthesized PG. Instead, surface-anchored Ebp was localized to the cell hemisphere but never at the septum where new cell wall is deposited. In addition, the older hemisphere of mid-division cells was completely saturated with Ebp, while at the newer hemisphere, Ebp appeared as two foci directly adjacent to the newly synthesized PG. When cell wall synthesis was inhibited by ramoplanin, an antibiotic that inhibits lipid II, new Ebp was still deposited at the cell surface. Based on these data, we propose an alternative paradigm for sortase substrate deposition in E. faecalis, in which Ebp can be anchored directly onto uncross-linked cell wall, independent of cell wall synthesis.Master of Scienc

Relationships between mental state vocabulary and theory of mind in children aged 18 months to 6 years old : a systematic review

This systematic review evaluated the quality of evidence of published studies reporting a relationship between mental state vocabulary and theory of mind (ToM) in children aged 18 months to 6 years, and documented the characterisation and operationalisation of mental state vocabulary and assessment of ToM skills. 1320 results obtained from PsycINFO on 10 February 2021 were screened to only include peer-reviewed journal articles of experimental or observational studies, published in English between 2011-2020, measuring children aged 18 months to 6 years for mental state vocabulary in the child’s language exposure or use, and ToM competence or performance in the child, leaving 19 studies to be included in the qualitative synthesis. Only 9 observational studies and 1 intervention study were found to have sufficient evidence; the remaining studies mostly lacked adequate power, blinding and access to supplementary materials and data, rendering them lower in quality of evidence and higher in risk of bias, based on quality indicators adapted from various sources. Insights from the current review include the complexity of ToM as a construct and its measurement issues, and a preference for elicitation methods. Recommendations include the standardisation of measures for both mental state vocabulary and ToM in the field, a review of validity and reliability of implicit ToM measures and the implementation of quality guidelines for all publications, to ensure their utility to the field of research. Review protocol was registered in DR-NTU (https://doi.org/10.21979/N9/5D9KVV).Bachelor of Arts in Psychology and Linguistics and Multilingual Studie

Feasibility of XBRL in public sector reporting.

This study explores the feasibility of implementing XBRL for Singapore public sector reporting. The findings show that the XBRL is feasible for financial reporting purposes and would increase the level of transparency to the public. The increase is achieved through higher accessibility to the reported data

Diversity and origins of giant guitarfish and wedgefish products in Singapore

10.1002/aqc.3553Aquatic Conservation: Marine and Freshwater Ecosystems3171636-164

Spatial and temporal localization of cell wall associated pili in Enterococcus faecalis

Enterococcus faecalis virulence requires cell wall-associated proteins, including the sortase-assembled endocarditis and biofilm associated pilus (Ebp), important for biofilm formation in vitro and in vivo. The current paradigm for sortase-assembled pilus biogenesis in Gram-positive bacteria is that sortases attach substrates to lipid II peptidoglycan (PG) precursors, prior to their incorporation into the growing cell wall. Contrary to prevailing dogma, by following the distribution of Ebp and PG throughout the E. faecalis cell cycle, we found that cell surface Ebp do not co-localize with newly synthesized PG. Instead, surface-exposed Ebp are localized to the older cell hemisphere and excluded from sites of new PG synthesis at the septum. Moreover, Ebp deposition on the younger hemisphere of the E. faecalis diplococcus appear as foci adjacent to the nascent septum. We propose a new model whereby sortase substrate deposition can occur on older PG rather than at sites of new cell wall synthesis. Consistent with this model, we demonstrate that sequestering lipid II to block PG synthesis via ramoplanin, does not impact new Ebp deposition at the cell surface. These data support an alternative paradigm for sortase substrate deposition in E. faecalis, in which Ebp are anchored directly onto uncrosslinked cell wall, independent of new PG synthesis.Ministry of Education (MOE)National Research Foundation (NRF)Published versionThis work was supported by National Research Foundation and Ministry of Education Singapore under its Research Centre of Excellence Programme, as well as the National Research Foundation under its Singapore NRF Fellowship programme (NRF-NRFF2011-11). This work was also supported by a Tier 1 grant sponsored by the Singapore Ministry of Education (MOE2017-T1- 001-269). Work in the VanNieuwenhze laboratory was supported by the National Institutes of Health (R35 GM136365)

Payment preferences of hawkers in Singapore : a discrete choice experiment

In this study, we aim to identify the underlying factors that affects the slow adoption of mobile payment in hawkers as compared to other industries. Using a discrete choice experiment to elicit willingness to pay, this study examined hawkers’ preference in payment methods by measuring the two main attributes – usage of smartphone and risk of fraud. Individual characteristics, business characteristics and knowledge, attitude, and practice (KAP) questions were also interacted with the main attributes to explore their impact on utility. Our results show that stallholders exhibit disutility and must be compensated $72.51 to use smartphone in their business operations. The main deterrent for adoption of mobile payment is the exposure to possibility of fraud. Stallholders have a linear WTP function with respect to the probability of fraud and must be compensated$149.24 for 3% risk of fraud relative to 2%. There is also a significant relationship between the location of the stall as well as stallholder’s preference of mobile payment. These results have important policy implications and will provide policymakers a holistic view of the general acceptance of mobile payment in the hawker business.Bachelor of Arts in Economic

Unraveling the trade in wedgefishes and giant guitarfishes in Singapore

Wedgefishes (Rhinidae) and giant guitarfishes (Glaucostegidae) are amongst the most threatened marine taxa globally. Research was undertaken in Singapore, a globally significant trading hub for shark and ray products, between May 2019 (two months after they were proposed for listing on the Convention on International Trade in Endangered Species of Flora and Fauna (CITES)) and August 2019 (three months before listings entered into force). The study documents the composition of imports and landings, estimates the scale of the trade, describes the supply chain, and analyzes completeness of product labels through surveys in fishery ports and retail markets as well as informal interviews with traders. Of 590 individuals recorded at fishery ports, 215 from six species could be identified to the species-level. Rhynchobatus australiae was the most commonly encountered wedgefish species (66%) while only one species of giant guitarfish (Glaucostegus typus) was recorded. Individuals were primarily claimed to be imported from Indonesia and Malaysia. The high value of wedgefish fins was evident as a large proportion of individuals without fins (66%) were recorded. Businesses in Singapore were utilizing by-products of the fin trade which appeared to have a distinct supply chain. Traders noted declining supplies of wedgefishes and dried shark fins in recent years. Shark and ray products notably lacked information on species and country of origin on their labels. Findings here provide baseline data for determining the effectiveness of new trade controls and suggest that a multi-pronged approach with trade monitoring, additional traceability and labeling requirements, and enhanced fisheries management would conserve globally declining, wild populations