Range Restricted Interpolation Using Cubic Bézier Triangles.

A range restricted C1 interpolation local scheme to scattered data is derived. Each macro triangle of the triangulated domain is split into three mini triangles and the interpolating surface on each mini triangle is a cubic Bézier triangle. Sufficient conditions derived for the non-negativity of these cubic Bézier triangles are expressed as lower bounds to the Bézier ordinates. The non-negativity preserving interpolation scheme extends to the construction of a range restricted interpolating surface with lower or upper constraints which are polynomial surfaces of degree up to three. The scheme is illustrated with graphical examples

Incremental cost-effectiveness analysis of gestational diabetes mellitus screening strategies in Singapore

10.1177/1010539515612908Asia-Pacific Journal of Public Health28115-25GUSTO (Growing up towards Healthy Outcomes

The influence of the environment and lifestyle on myopia

Background: Myopia, commonly known as near-sightedness, has emerged as a global epidemic, impacting almost one in three individuals across the world. The increasing prevalence of myopia during early childhood has heightened the risk of developing high myopia and related sight-threatening eye conditions in adulthood. This surge in myopia rates, occurring within a relatively stable genetic framework, underscores the profound influence of environmental and lifestyle factors on this condition. In this comprehensive narrative review, we shed light on both established and potential environmental and lifestyle contributors that affect the development and progression of myopia. Main body: Epidemiological and interventional research has consistently revealed a compelling connection between increased outdoor time and a decreased risk of myopia in children. This protective effect may primarily be attributed to exposure to the characteristics of natural light (i.e., sunlight) and the release of retinal dopamine. Conversely, irrespective of outdoor time, excessive engagement in near work can further worsen the onset of myopia. While the exact mechanisms behind this exacerbation are not fully comprehended, it appears to involve shifts in relative peripheral refraction, the overstimulation of accommodation, or a complex interplay of these factors, leading to issues like retinal image defocus, blur, and chromatic aberration. Other potential factors like the spatial frequency of the visual environment, circadian rhythm, sleep, nutrition, smoking, socio-economic status, and education have debatable independent influences on myopia development. Conclusion: The environment exerts a significant influence on the development and progression of myopia. Improving the modifiable key environmental predictors like time spent outdoors and engagement in near work can prevent or slow the progression of myopia. The intricate connections between lifestyle and environmental factors often obscure research findings, making it challenging to disentangle their individual effects. This complexity underscores the necessity for prospective studies that employ objective assessments, such as quantifying light exposure and near work, among others. These studies are crucial for gaining a more comprehensive understanding of how various environmental factors can be modified to prevent or slow the progression of myopia

The dynamics of ageing in Singapore's population

Annals of the Academy of Medicine Singapore144709-713AAMS

OPTIMISATION OF NEON SXR (SOFT X-RAY) YIELD OF THE INTI PLASMA FOCUS MACHINE AT 12 kV

The INTI plasma focus machine is a 3 kJ Mather type plasma focus machine,powered by a single Maxwell capacitor. The system produces remarkable consistent focusing action in neon, making it a suitable source for the production of high energy photons, electrons, ions and neon soft x-rays (SXR) [1, 2]. The aim of this paper is to optimise the neon SXR yield of the INTI plasma focus machine operated at 12 kV by parametrically, changing the anode dimensions (radius and length) using the Lee Model Code (version RADPFV5.15dd). Results of the optimisation procedures resulted in a neon SXR yield of 6.47 J at 2.5 torr and 12 kV, with a shorter length and a fatter anode radius of 7.9 cm and 1.2 cm respectively. This gives an improvement in the neon SXR yield of 40% when compares to neon SXR yield of 2.74 J at 2.5 torr 12 kV with the present configurations

Rare earth elements in malaysia: Overview of processing, sustainability and environmental impact

In Malaysia, there were two rare earths processing plants namely Asian Rare Earth (ARE) and the Malaysian Rare Earth Corporation Plant (MAREC) in Perak, which were operated until 1992 and were subsequently closed due to problems pertaining to disposal of large amount of radioactive waste. Recently, Lynas Advanced Materials Plant (LAMP) has become one of the largest rare earths processing plant in the world producing rare earth elements (REE) in Gebeng, Pahang. The primary raw material is lanthanide concentrate (LC) which is imported from Mount Weld mine in Australia and shipped to Malaysia. LC is produced from lanthanide ore after mining and mineral processing. The ore has a lower impact than Bayan Obo, Mountain Pass and adsorbed clay deposits, given the small footprint of the mine itself and the remoteness of the location. The type of ore being mined (rare earth phosphates: carbonatite, monazite) may have higher thorium content than bastnasite ore from the Chinese or American mines but still far below radiation concerns. This paper was written to review the processing flowsheet at the Lynas Advanced Materials Plant (LAMP), the environmental impact associated with the processing of the said ores and the sustainability of the operation. © 2017 TAPPI Press. All rights reserved

Damage Study of Irradiated Tungsten using fast focus mode of a 2.2 kJ plasma focus

In this work, damage results of four 12 mm × 12 mm × 5 mm PLANSEE double forged tungsten target samples exposed in INTI PF device at different distances from anode operating in the fast focus mode at 12 kV, 2.5 Torr deuterium are presented. SEM and EDX images and analysis show the extent of damage on the exposed tungsten surface. Micro-cracks up to 300 nm and 500 nm to 5 μm holes together with signs of melting are found on the tungsten exposed surfaces depending on their distances from the anode top. Current waveforms fitting using Lee Model Code show yields of 3 × 106 neutrons and 8.5 × 1014 ions per shot with average ion energy of 56 keV per ion at pinch exit, generating heat flux of 1.8 × 1014 Wm−2 and damage factor (also called heat flux factor) of 1.6 × 1010 Wm−2s0.5 on a target at pinch exit

The study of pinch regimes based on radiation-enhanced compression and anomalous resistivity phenomena and their effects on hard x-ray emission in a Mather type dense plasma focus device (SABALAN2)

In this study, by using argon and nitrogen as the filling gases in a Mather type dense plasma focus device at different values of pressure and charging voltage, two different kinds of pinch regimes were observed for each of the gases. The physics of the pinch regimes could be explained by using the two versions of the Lee's computational model which predicted each of the scenarios and clarified their differences between the two gases according to the radiation-enhanced compression and, additionally, predicted the pinch regimes through the anomalous resistivity effect during the pinch time. This was accomplished through the fitting process (simulation) on the current signal. Moreover, the characteristic amplitude and time scales of the anomalous resistances were obtained. The correlations between the features of the plasma current dip and the emitted hard x-ray pulses were observed. The starting time, intensity, duration, and the multiple or single feature of the emitted hard x-ray strongly correlated to the same respective features of the current dip. (C) 2015 AIP Publishing LLC