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Aim To estimate whether species have shifted at equal rates at their leading edges (cool boundaries) and trailing edges (warm boundaries) in response to climate change. We provide the first such evidence for tropical insects, here examining elevation shifts for the upper and lower boundaries shifts of montane moths. Threats to species on tropical mountains are considered.Location Mount Kinabalu, Sabah, Malaysia.Methods We surveyed Lepidoptera (Geometridae) on Mount Kinabalu in 2007, 42 years after the previous surveys in 1965. Changes in species upper and lower boundaries, elevational extents and range areas were assessed. We randomly subsampled the data to ensure comparable datasets between years. Estimated shifts were compared for endemic versus more widespread species, and for species that reached their range limits at different elevations.Results Species that reached their upper limits at 2500-2700 m (n= 28 species, 20% of those considered) retreated at both their lower and upper boundaries, and hence showed substantial average range contractions (-300 m in elevational extent and -45 km2 in estimated range area). These declines may be associated with changes in cloud cover and the presence of ecological barriers (geological and vegetation transitions) which impede uphill movement. Other than this group, most species (n= 109, 80% of the species considered) expanded their upper boundaries upwards (by an average of 152 m) more than they retreated at their lower boundaries (77 m).Main conclusions Without constraints, leading margins shifted uphill faster than trailing margins retreated, such that many species increased their elevational extents. However, this did not result in increases in range area because the area of land available declines with increasing elevation. Species close to a major ecological/geological transition zone on the mountain flank declined in their range areas. Extinction risk may increase long before species reach the summit, even when undist

Calcium-alginate hydrogel is commonly used to encapsulate live cells. However, the qualities of lyophilized alginate beads could be undesirable for various reasons which may include reduction in encapsulation performance during storage. The objectives of this work were to improve the qualities of the lyophilized beads and to establish evidence if the bead qualities had significant influence on the stability of encapsulated cells. The bead qualities were manipulated by incorporating corn starch as the solid filler at various concentrations and produced using simple extrusion technique and subsequently lyophilized. The degree of shrinkage of SFAB during lyophilization was found to be dependent on the filler concentration with the control beads shrunk the most, by about 40% whereas the shrinkage reduced where beads shrunk from 18% to 9% with additional of starch filler. Sphericity of SFAB was also improved with Aspect Ratio of between 1.1 and unity. The relative porosity reduced from 71% (control sample) to 21.7% (SFAB 60%) in a near linear trend and SFAB was found to have ink bottle pore shape. With incorporation of starch fillers, SFAB with higher starch concentration had greater mechanical strength but its mechanical behavior changed from spongy to brittle with a breakage point observed in the stress strain curve of starch concentration above 40%. Less hygroscopic behaviour was also observed from the lower EMC, range from 15% to 25% of SFAB with additional of starch compared to the control beads of EMC above 30%. Probiotic cells encapsulated within the alginate-starch beads were significantly more stable during freeze-drying process and storage, exposed to temperature, humidity and oxygen stresses in comparison to the cells encapsulated within the control beads. It is believed that with the Incorporation of starch granules, stabilization on cells could occur In three possible mechanisms which are 1) shielding effect by the physical packing of starch granules 2) main

The main objective of this work is to improve the physical properties of lyophilized calcium (Ca)–alginate beads as a carrier material for the stabilization of encapsulated living cells. Improvements in the sphericity, flowability and mechanical strength of the dried beads were attributed to the filler, which provided structure and reinforcement to the Ca–alginate hydrogel networks, as verified by X-ray microtomography and scanning electron microscopy. A quantitative analysis of the micro-images revealed the less porous nature of the alginate–starch beads compared to the control. The beads with filler were also found to be less hygroscopic. The results also show that the cells encapsulated within the beads with reduced porosity and hygroscopicity were clearly more stable during lyophilization and storage than the control. In conclusion, the qualities of the alginate beads were improved by incorporating the solid filler, and the filler had a significant influence on cell viability during lyophilization and storage.

The main objective of this work is to improve the physical properties of lyophilized calcium (Ca)–alginate beads as a carrier material for the stabilization of encapsulated living cells. Improvements in the sphericity, flowability and mechanical strength of the dried beads were attributed to the filler, which provided structure and reinforcement to the Ca–alginate hydrogel networks, as verified by X-ray microtomography and scanning electron microscopy. A quantitative analysis of the micro-images revealed the less porous nature of the alginate–starch beads compared to the control. The beads with filler were also found to be less hygroscopic. The results also show that the cells encapsulated within the beads with reduced porosity and hygroscopicity were clearly more stable during lyophilization and storage than the control. In conclusion, the qualities of the alginate beads were improved by incorporating the solid filler, and the filler had a significant influence on cell viability during lyophilization and storage.