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Singapore is a rapidly ageing society, underpinned by national policies to promote successful and active ageing. Whilst older worker participation in the workforce is encouraged, policymakers are challenged to ensure that work competency is not compromised with any normal age- and/or health-related changes. This paper will briefly outline how policymakers responded to the needs of two subgroups of older workers aged 70 years and above (taxi drivers; crane operators) who desire to continue working in the last two decades. Whilst a mandatory retirement age policy exists for older taxi drivers in Singapore, there is none for older crane operators. Despite this, stricter relicensing protocols were introduced for both types of workers, with active collaboration involving additional occupational therapy services for functional work competency assessments to complement the routine medical fitness screening. Comparisons will be made of these two relicensing frameworks, including the mention of any relevant studies to align with the call of evidence-based practices. In mid-2020, the relicensing policy for older taxi drivers was revised based on findings of a retrospective national database study. Currently, a 4-year national database study on older crane operators aged 70 years and above is being undertaken with preliminary findings to be reported.

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CURT1 proteins in 'Arabidopsis thaliana' have been reported to be important for inducing grana curvature. Currently, we have identified transcript encoding CURT1A from 'Oryza sativa' cv. indica through RNA-seq analysis and characterised using heterologous system in Arabidopsis. The 'OsCURT1A' gene shares 80% of its amino acid sequence with Arabidopsis 'AtCURT1A'. Phylogenetic analysis revealed that the 'OsCURT1A' is also closely related to the CURT1 proteins in other choloroplast- conatining organisms. In silico analysis of OsCURT1A promoter shows that several cis-elements related to stress are present in the 5' upstream from the coding region. Under normal conditions, there were no notable changes in the phenotype and chlorophyll a;b ratio between three Arabidopsis genotypes, which were overexpressed (35S::'OsCURT1A'), T-DNA insertional mutant line ('atcurt1a'), and Wild type (Col-0). However, overexpression of 'OsCURT1A' under salinity condition demonstrate high chlorophyll a:b compared to Col-0, whereas, the lack of atcurt1a gene in the mutant line showed reduced chlorophyll a:b ratio. These results indicate that the 'OsCURT1A' might have a function as salt-stress related gene, which may indirectly regulate the chlorophyll a:b ratio. Therefore, 'OsCURT1A' can be used as a potential candidate for salinity stress tolerance in crop improvement.

Citral is a mixture of neral and geranial, which are of great interest to the fragrance industry due to its lemon-scented aroma. A newly characterized nerol dehydrogenase of Persicaria minor (PmNeDH) from our recent findings has shown a capacity to convert citral from nerol. Differential gene expression analysis revealed that the expression level of PmNeDH was highly upregulated during early treatment of several stress-related phytohormones i.e. methyl jasmonate (MeJA), salicylic acid (SA) and abscisic acid (ABA). SA and ABA were shown to have a prolonged effect on PmNeDH expression level until second day of treatment. The findings were in agreement with the cis-regulatory elements predicted from the gene promoter. The phylogenetic relationship of PmNeDH with its homologs from the medium-chain dehydrogenases/reductases (MDR) superfamily was also mentioned. In this study, we proposed a possible biological function of PmNeDH gene in P. minor, which might play significant roles in plant defence mechanism.

Highlights • We report 5 patients with mesial temporal lobe epilepsy with a benign course. • Seizure onset is late and seizures respond well to medications. • Seizures at the onset can be minor and easily missed. • Serious consequences such as motor vehicle crashes can occur in the untreated. • Awareness is important to diagnose cases early to prevent potential complications., Mesial temporal lobe epilepsy, a well-characterized epilepsy syndrome, is most commonly accompanied by the pathological feature of hippocampal sclerosis. Patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) typically present in childhood to early adolescence. We describe a cohort of patients who presented with their first epileptic seizure in late adulthood with atypical features. We characterized five patients with late-onset MTLE-HS by describing their demographics, electroclinical features, imaging, autoantibody status, and response to antiseizure medication (ASM) therapy. All five patients had their first seizure after the age of 50 with no history of initial precipitating incidents. None of our patients had positive serum or CSF autoantibodies and they have all remained seizure-free for a minimum of two years on ASMs alone. Two patients had motor vehicle crashes associated with seizures whilst three patients experienced seizures in sleep. A milder form of MTLE, previously described as benign TLE, does exist in routine clinical practice. These patients respond well to ASM therapy, but potentially harmful consequences such as motor vehicle crashes can occur in the untreated.

Material removal at the sub-micron level has been a topic of interest in the past few years, particularly with respect to the fabrication of miniaturized devices. While numerous techniques have been developed and refined from their larger meso-scale counterparts (e.g. polishing), most have inherent limitations (such as the introduction of scratches from polishing) which may render these processes to be less attractive. In this work, a novel non-contact technique (where the machining tool is not in contact with the workpiece [1-4]) of using electrokinetic phenomenon for precise material removal (a.k.a electrokinetic material removal process) at rates in the order of nanometers/min is introduced. The technique involves movements of abrasive particles in a fluidic flow, under the influence of an AC electric field with a DC offset, to collide with the surface of the material to achieve material removal. Results showed that the technique is feasible in achieving material removal up to a depth of several hundred nanometers. Parametric studies on the material removal, which include material removal rate (MRR) and surface roughness (SR), were carried out and documented. A semi-empirical model on the material removal rate (MRR) was subsequently proposed after the dominating material removal mechanism was identified. The model was further validated with additional experimental results to show its predictive capability. With no chemicals involved in the process, the technique offers the further attraction of being a benign nano-manufacturing process with potential usage in the microelectromechanical systems (MEMS) areas. DOCTOR OF PHILOSOPHY (MAE)

Geraniol degradation pathway has long been elucidated in microorganisms through bioconversion studies, yet weakly characterised in plants; enzyme with specific nerol-oxidising activity has not been reported. A novel cDNA encodes nerol dehydrogenase (PmNeDH) was isolated from Persicaria minor. The recombinant PmNeDH (rPmNeDH) is a homodimeric enzyme that belongs to MDR (medium-chain dehydrogenases/reductases) superfamily that catalyses the first oxidative step of geraniol degradation pathway in citral biosynthesis. Kinetic analysis revealed that rPmNeDH has a high specificity for allylic primary alcohols with backbone ≤10 carbons. rPmNeDH has ∼3 fold higher affinity towards nerol (cis-3,7-dimethyl-2,6-octadien-1-ol) than its trans-isomer, geraniol. To our knowledge, this is the first alcohol dehydrogenase with higher preference towards nerol, suggesting that nerol can be effective substrate for citral biosynthesis in P. minor. The rPmNeDH crystal structure (1.54 A) showed high similarity with enzyme structures from MDR superfamily. Structure guided mutation was conducted to describe the relationships between substrate specificity and residue substitutions in the active site. Kinetics analyses of wild-type rPmNeDH and several active site mutants demonstrated that the substrate specificity of rPmNeDH can be altered by changing any selected active site residues (Asp280, Leu294 and Ala303). Interestingly, the L294F, A303F and A303G mutants were able to revamp the substrate preference towards geraniol. Furthermore, mutant that exhibited a broader substrate range was also obtained. This study demonstrates that P. minor may have evolved to contain enzyme that optimally recognise cis-configured nerol as substrate. rPmNeDH structure provides new insights into the substrate specificity and active site plasticity in MDR superfamily.

The dataset presented in this article describes microarray experiment of Auxin-binding protein 57, Abp57-overexpressing transgenic rice. The gene expression profiles were generated using Affymetrix GeneChip® Rice (Cn) Gene 1.0 ST Arrays. Total RNA from seedlings tissue of transgenic rice and wildtype, which serve as control were used as starting materials for microarray experiment. Detailed experimental methods and data analysis were described here. The raw and normalized microarray data were deposited into Gene Expression Omnibus (GEO) under accession number GSE99055.

TylP is one of five regulatory proteins involved in the regulation of antibiotic (tylosin) production, morphological and physiological differentiation inStreptomyces fradiae. Its function is similar to those of various γ-butyrolactone receptor proteins. In this report, N-terminally His-tagged recombinant TylP protein (rTylP) was overproduced inEscherichia coliand purified to homogeneity. The rTylP protein was crystallized from a reservoir solution comprising 34%(v/v) ethylene glycol and 5%(v/v) glycerol. The protein crystals diffracted X-rays to 3.05 Å resolution and belonged to the trigonal space groupP3121, with unit-cell parametersa=b= 126.62,c= 95.63 Å.

Agarwood is a resinous part of the non-timber Aquilaria tree, which is a highly valuable product for medicine and fragrance purposes. To protect the endangered Aquilaria species, mass plantation of Aquilaria trees has become a sustainable way in Asian countries to obtain the highly valuable agarwood. As only physiologically triggered Aquilaria tree can produce agarwood, effective induction methods are long sought in the agarwood industry. In this paper, we attempt to provide an overview for the past efforts toward the understanding of agarwood formation, the evolvement of induction methods and their further development prospects by integrating it with high-throughput omics approaches.

Non-contact material removal processes offer numerous advantages over traditional machining approaches and nowhere is this more apparent than in the fabrication of micro devices. Current micromachining techniques such as microgrinding and micromilling have limitations with respect to their positioning accuracy and tool deflections. Electro thermal processes such as microEDM and laser machining usually result in a heat affected zone being produced. Other approaches such as etching and non-contact ultraprecision polishing are either costly or are not suitable for high throughput. In order to address these limitations, alternative micromachining techniques are required. In this paper, a non-contact material removal technique based on the electrokinetic phenomenon is proposed for precise material removal at rates in the order of nanometers/min. The aim of this research is to have a better understanding on the electrokinetic material removal technique by studying the trajectory of the particles and the influence of the frequency of the electric field on the material removal rate.

A full understanding of the microenvironmental factors that control the activities of skeletal stem cells (also known as mesenchymal stem cells [MSCs]) in the adult bone marrow holds great promise for developing new therapeutic strategies to mitigate age-related diseases of bone and cartilage degeneration. Bone loss is an understudied manifestation of Marfan syndrome, a multisystem disease associated with mutations in the extracellular matrix protein and TGFβ modulator fibrillin-1. Here we demonstrate that progressive loss of cancellous bone in mice with limbs deficient for fibrillin-1 (Fbn1(Prx1-/-) mice) is accounted for by premature depletion of MSCs and osteoprogenitor cells combined with constitutively enhanced bone resorption. Longitudinal analyses of Fbn1(Prx1-/-) mice showed incremental bone loss and trabecular microarchitecture degeneration accompanied by a progressive decrease in the number and clonogenic potential of MSCs. Significant paucity of marrow fat cells in the long bones of Fbn1(Prx1-/-) mice, together with reduced adipogenic potential of marrow stromal cell cultures, indicated an additional defect in MSC differentiation. This postulate was corroborated by showing that an Fbn1-silenced osteoprogenitor cell line cultured in the presence of insulin yielded fewer than normal adipocytes and exhibited relatively lower PPARγ levels. Consonant with fibrillin-1 modulation of TGFβ bioavailability, cultures of marrow stromal cells from Fbn1(Prx1-/-) limb bones showed improper overactivation of latent TGFβ. In line with this finding, systemic TGFβ neutralization improved bone mass and trabecular microarchitecture along with normalizing the number of MSCs, osteoprogenitor cells, and marrow adipocytes. Collectively, our findings show that fibrillin-1 regulates MSC activity by modulating TGFβ bioavailability within the microenvironment of marrow niches.

Background— Adrenergic activation is thought to be an important determinant of outcome in subjects with chronic heart failure (CHF), but baseline or serial changes in adrenergic activity have not been previously investigated in a large patient sample treated with a powerful antiadrenergic agent. Methods and Results— Systemic venous norepinephrine was measured at baseline, 3 months, and 12 months in the β-Blocker Evaluation of Survival Trial (BEST), which compared placebo treatment with the β-blocker/sympatholytic agent bucindolol. Baseline norepinephrine level was associated with a progressive increase in rates of death or death plus CHF hospitalization that was independent of treatment group. On multivariate analysis, baseline norepinephrine was also a highly significant ( P Conclusions— In BEST, a subset of patients treated with bucindolol had an increased risk of death as the result of sympatholysis, which compromised the efficacy of this third-generation β-blocker.

Material removal at the sub-micron level has been a topic of interest in the past few years, particularly with respect to the fabrication of miniaturized devices. While numerous techniques have been developed and refined from their larger mesoscale counterparts (e.g. microEDM, micromilling), most have inherent limitations such as tool dimensions restricting the minimum feature which can be produced. In this work, we are proposing a novel technique of using the electrokinetic phenomenon for precise material removal at rates in the order of nanometers/min. An AC electric field with a DC offset is applied to a flowing fluid containing suspended particles which will then collide with the workpiece material causing material wear and tear and thus material removal. Results showed that the technique was feasible in achieving sub-micron material removal in micro-channels up to a depth of several hundred nanometers. With no chemicals involved in the process, the technique offers the further attraction of being a benign nano-manufacturing process with potential usage in the biochip and microfluidics areas.

Photolithography is the most important process used to pattern the surface of silicon wafers in IC fabrication.It has shown high performance but its use is not cost-eective for small series or prototyping as it necessitatesa costly infrastructure (mask aligner) and requires the fabrication of masks which can be expensive and time-consuming. Recently, the high resolution achieved by ink-jet printer ( > 1200 DPI) starts to make an interestingalternative to obtain a patterned protective layer instead of using photolithography. This is particularly true forMEMS which often need a resolution of only 10 to 20 µ m.After studying the dierent architecture of inkjet printer available in the market, a commercial S$100-printerwas selected and modi“ed to allow printing on a rigid silicon wafer. We then developed three dierent patterningprocesses using the printer. In a “rst process the ink was directly used as a protective layer for patterning.A second process modi“ed the photolithography by using the printed ink as a photo-mask on a spun layer ofphotoresist. In each case we had to modify the surface energy of the wafer by surface treatment to improve theresolution. Finally we replaced the ink with a modi“ed photoresist solution and directly printed a protectivemask onto the wafer. Design of Experiment (DOE) methods were systematically employed to study the mainand interaction eects of the parameters on the lithography and on the pattern transfer.The series of experiment showed that o-the-shelf ink-jet printer could be used easily for pattern with aresolution below 50 µ m, but could not yet reach the 20 µ m range.Keywords: maskless lithography, inkjet printing, surface modi“cation, contact angle, plasma treatment

Fuzzy controllers implemented in hardware can operate with much higher performance than software implementations on standard microcontrollers. In this paper, a dynamic fuzzy logic controller (FLC) and its hardware architectures are proposed. The FLC is realized on a CLPD chip. The presented circuits can dynamically generate fuzzy inference results when they are activated, so there is no need to design a large scale of ROM to store the fuzzy rules. Even we increase the resolutions of input and output variables and the universes of discourses, the increments of the gate counts are very few. Finally, a garage parking control system is used to demonstrate the effectiveness of the developed chip.

We demonstrated a novel optical signal modulation by the interaction of spatial solitons generated from a semiconductor ridge waveguide circular ring resonator with an input signal from the Y-junction coupling section. By controlling the optical power of the circular ring resonator with emission at 660 nm, in which a spatial soliton waveguide is formed owing to the photorefractive effect, one can manipulate the transmission of the input signal through the soliton waveguide. For an input signal of 1560 nm, the transmission through this soliton waveguide can be modulated within a 10 dB depth. The fabrication and optical properties of the fabricated devices are presented.