Modelling ranging behaviour of female orang-utans: a case study in Tuanan, Central Kalimantan, Indonesia

Quantification of the spatial needs of individuals and populations is vitally important for management and conservation. Geographic information systems (GIS) have recently become important analytical tools in wildlife biology, improving our ability to understand animal movement patterns, especially when very large data sets are collected. This study aims at combining the field of GIS with primatology to model and analyse space-use patterns of wild orang-utans. Home ranges of female orang-utans in the Tuanan Mawas forest reserve in Central Kalimantan, Indonesia were modelled with kernel density estimation methods. Kernel results were compared with minimum convex polygon estimates, and were found to perform better, because they were less sensitive to sample size and produced more reliable estimates. Furthermore, daily travel paths were calculated from 970 complete follow days. Annual ranges for the resident females were approximately 200 ha and remained stable over several years; total home range size was estimated to be 275 ha. On average, each female shared a third of her home range with each neighbouring female. Orang-utan females in Tuanan built their night nest on average 414 m away from the morning nest, whereas average daily travel path length was 777 m. A significant effect of fruit availability on day path length was found. Sexually active females covered longer distances per day and may also temporarily expand their ranges

The study of atmospheric ice-nucleating particles via microfluidically generated droplets

Ice-nucleating particles (INPs) play a significant role in the climate and hydrological cycle by triggering ice formation in supercooled clouds, thereby causing precipitation and affecting cloud lifetimes and their radiative properties. However, despite their importance, INP often comprise only 1 in 10³–10⁶ ambient particles, making it difficult to ascertain and predict their type, source, and concentration. The typical techniques for quantifying INP concentrations tend to be highly labour-intensive, suffer from poor time resolution, or are limited in sensitivity to low concentrations. Here, we present the application of microfluidic devices to the study of atmospheric INPs via the simple and rapid production of monodisperse droplets and their subsequent freezing on a cold stage. This device offers the potential for the testing of INP concentrations in aqueous samples with high sensitivity and high counting statistics. Various INPs were tested for validation of the platform, including mineral dust and biological species, with results compared to literature values. We also describe a methodology for sampling atmospheric aerosol in a manner that minimises sampling biases and which is compatible with the microfluidic device. We present results for INP concentrations in air sampled during two field campaigns: (1) from a rural location in the UK and (2) during the UK’s annual Bonfire Night festival. These initial results will provide a route for deployment of the microfluidic platform for the study and quantification of INPs in upcoming field campaigns around the globe, while providing a benchmark for future lab-on-a-chip-based INP studies

Lumbar disc degeneration is associated with modic change and high paraspinal fat content – a 3.0T magnetic resonance imaging study

BACKGROUND: Degenerative disc disease of the lumbar spine is common, with severe disease increasing the risk for chronic low back pain. This cross-sectional study examined whether disc degeneration is representative of a ‘whole-organ’ pathology, by examining its association with bone (vertebral endplate) and soft tissue (paraspinal muscle fat) abnormalities. METHODS: Seventy-two community-based individuals unselected for low back pain, had Magnetic Resonance Imaging (MRI). Lumbosacral disc degeneration was determined via the Pfirrmann grading system, a validated method to assess the intervertebral disc, distinguishing the nucleus and annulus, the signal intensity and the height of the intervertebral disc. Modic change and high paraspinal muscle fat content was also measured from MRI. RESULTS: Severe disc degeneration was associated, or tended to be associated with type 2 Modic change from L2 to L5 (OR range 3.5 to 25.3, p ≤ 0.06). Moreover, severe disc degeneration at all intervertebral levels was associated with or tended to be associated with high fat content of the paraspinal muscles (OR range 3.7 to 14.3, p ≤ 0.09). CONCLUSION: These data demonstrate that disc degeneration of the lumbar spine is commonly accompanied by Modic change and high fat content of paraspinal muscles, thus representing a ‘whole-organ’ pathology. Longitudinal studies are required to determine the temporal relationship between these structural abnormalities. Understanding this may have the potential to identify novel targets for the treatment and prevention of lumbosacral disc degeneration