A cost-effective high-throughput digital system for observation and acquisition of animal behavioral data

We have designed and implemented a low-cost digital system using closed-circuit television cameras coupled to a digital acquisition system for the recording of in vivo behavioral data in rodents and for allowing observation and recording of more than 10 animals simultaneously at a reduced cost, as compared with commercially available solutions. This system has been validated using two experimental rodent models: one involving chemically induced seizures and one assessing appetite and feeding. We present observational results showing comparable or improved levels of accuracy and observer consistency between this new system and traditional methods in these experimental models, discuss advantages of the presented system over conventional analog systems and commercially available digital systems, and propose possible extensions to the system and applications to nonrodent studies.

The use of earth observation techniques to improve catchment-scale pollution predictions

Remote sensing can potentially provide information useful in improving pollution transport modelling in agricultural catchments. Realisation of this potential will depend on the availability of the raw data, development of information extraction techniques, and the impact of the assimilation of the derived information into models. High spatial resolution hyperspectral imagery of a farm near Hereford, UK is analysed. A technique is described to automatically identify the soil and vegetation endmembers within a field, enabling vegetation fractional cover estimation. The aerially-acquired laser altimetry is used to produce digital elevation models of the site. At the subfield scale the hypothesis that higher resolution topography will make a substantial difference to contaminant transport is tested using the AGricultural Non-Point Source (AGNPS) model. Slope aspect and direction information are extracted from the topography at different resolutions to study the effects on soil erosion, deposition, runoff and nutrient losses. Field-scale models are often used to model drainage water, nitrate and runoff/sediment loss, but the demanding input data requirements make scaling up to catchment level difficult. By determining the input range of spatial variables gathered from EO data, and comparing the response of models to the range of variation measured, the critical model inputs can be identified. Response surfaces to variation in these inputs constrain uncertainty in model predictions and are presented. Although optical earth observation analysis can provide fractional vegetation cover, cloud cover and semi-random weather patterns can hinder data acquisition in Northern Europe. A Spring and Autumn cloud cover analysis is carried out over seven UK sites close to agricultural districts, using historic satellite image metadata, climate modelling and historic ground weather observations. Results are assessed in terms of probability of acquisition probability and implications for future earth observation missions. (C) 2003 Elsevier Ltd. All rights reserved.

Teleconnections between Ethiopian summer rainfall and sea surface temperature: part I. Observation and modelling

In this study, the oceanic regions that are associated with anomalous Ethiopian summer rains were identified and the teleconnection mechanisms that give rise to these associations have been investigated. Because of the complexities of rainfall climate in the horn of Africa, Ethiopia has been subdivided into six homogeneous rainfall zones and the influence of SST anomalies was analysed separately for each zone. The investigation made use of composite analysis and modelling experiments. Two sets of composites of atmospheric fields were generated, one based on excess/deficit rainfall anomalies and the other based on warm/cold SST anomalies in specific oceanic regions. The aim of the composite analysis was to determine the link between SST and rainfall in terms of large scale features. The modelling experiments were intended to explore the causality of these linkage. The results show that the equatorial Pacific, the midlatitude northwest Pacific and the Gulf of Guinea all exert an influence on the summer rainfall in various part of the country. The results demonstrate that different mechanisms linked to sea surface temperature control variations in rainfall in different parts of Ethiopia. This has important consequences for seasonal forecasting models which are based on statistical correlations between SST and seasonal rainfall totals. It is clear that such statistical models should take account of the local variations in teleconnections.

Observation and origin of an interannual salinity anomaly in the Mozambique Channel

A positive salinity anomaly of 0.2 PSU was observed between 50 and 200 m over the years 2000–2001 across the Mozambique Channel at a section at 17°S which was repeated in 2003, 2005, 2006, and 2008. Meanwhile, a moored array is continued from 2003 to 2008. This anomaly was most distinct showing an interannual but nonseasonal variation. The possible origin of the anomaly is investigated using output from three ocean general circulation models (Estimating the Circulation and Climate of the Ocean, Ocean Circulation and Climate Advanced Modeling, and Parallel Ocean Program). The most probable mechanism for the salinity anomaly is the anomalous inflow of subtropical waters caused by a weakening of the northern part of the South Equatorial Current by weaker trade winds. This mechanism was found in all three numerical models. In addition, the numerical models indicate a possible salinization of one of the source water masses to the Mozambique Channel as an additional cause of the anomaly. The anomaly propagated southward into the Agulhas Current and northward along the African coast.

In situ observation of lithium hydride hydrolysis by DRIFT spectroscopy

Polycrystalline LiH was studied in situ using diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy to investigate the effect water vapour has on the rate of production of the corrosion products, particularly LiOH. The reaction rate of the formation of surface LiOH was monitored by measurement of the hydroxyl (OH) band at 3676 cm(-1). The initial hydrolysis rate of LiH exposed to water vapour at 50% relative humidity was found to be almost two times faster than LiH exposed to water vapour at 2% relative humidity. The hydrolysis rate was shown to be initially very rapid followed by a much slower, almost linear rate. The change in hydrolysis rate was attributed to the formation of a coherent layer of LiOH on the LiH surface. Exposure to lower levels of water vapour appeared to result in the formation of a more coherent corrosion product, resulting in effective passivation of the surface to further attack from water. Crown Copyright (c) 2007 Published by Elsevier B.V. All rights reserved.

SAXS observation of RCM1 under cyclical shear

A cylinder forming poly(styrene-b-butadiene-b-styrene) triblock copolymer melt is cyclically processed through a capillary at a high shear rate in the Cambridge Multipass Rheometer (MPR). In situ X-ray diffraction experiments enable observation of the effect of the shear on the block copolymer (BCP) nanophase orientation, both during and after processing. Temporal resolution of the X-ray exposures is increased, whilst retaining intensity, by exploiting the cyclical nature of the shear and the material's response to it; short exposures from many cycles, individually having few counts, are added together to produce well resolved X-ray patterns. Orientation of the cylinders reduces during processing, then increases during pauses between processing. The loss of orientation is attributed to the high shear rate deforming the melt faster than the structure can respond, whilst it is believed that melt relaxation, linked to the compressibility of the material, produces much lower shear rates after mechanical processing has ceased, which induces strong orientation of the nanostructure.