Technical note: Use of accelerometers to describe gait patterns in dairy calves

Developments in accelerometer technology offer new opportunities for automatic monitoring of animal behavior. Until now, commercially available accelerometers have been used to measure walking in adult cows but have failed to identify walking in calves. We described the pattern of acceleration associated with various gaits in calves and tested whether measures of acceleration could be used to count steps and distinguish among gait types. A triaxial accelerometer (sampling at 33 readings/s with maximum measurement at ±3.2 g) was attached to 1 hind leg of 7 dairy calves, and each calf was walked to a familiar large arena (29.1 × 4.8 m) and encouraged to walk and run for 8 to 10 min while being video recorded. The video recordings were watched in slow motion and a total of 54 recordings of 3 to 6 s duration of either galloping (n = 21), trotting (n = 13), or walking (n = 21) were identified and the number of steps were counted. Accelerometer data was then analyzed for each gait. Steps could be clearly identified by changes in the acceleration in the forward and vertical axes and vector sum, but less clearly in the lateral axis. The number of steps counted using the forward axis was highly correlated with the number observed from the video recordings. Galloping, trotting, and walking differed significantly in the median interpeak intervals in acceleration in the forward axis and in the vector sum of the acceleration in the 2 axes. Interpeak intervals could be used to discriminate among the 3 gaits, although walking was most clearly distinguished from galloping. Automated measures of acceleration of the leg in the forward and vertical dimensions can be used to count steps and classify gaits of calves.     

A chromodomain protein encoded by the arabidopsis CAO gene is a plant-specific component of the chloroplast signal recognition particle pathway that is involved in LHCP targeting

Adjustment outcomes of 224 transracial and inracial adoptees were investigated using data collected over 17 years. Findings reveal an association between adoptees' outcomes and their race, gender, and adoptive family structure. Placement history was not significant. Implications for policy and practice are discussed, as are future directions for research.     

A 3.3-V single-poly CMOS audio ADC delta-sigma modulator with 98-dB peak SINAD and 105-dB peak SFDR

This paper presents a second-order ΔΣ modulator for audio-band analog-to-digital conversion implemented in a 3.3-V, 0.5-μm, single-poly CMOS process using metal-metal capacitors that achieves 98-dB peak signal-to-noise-and-distortion ratio and 105-dB peak spurious-free dynamic range. The design uses a low-complexity, first-order mismatch shaping 33-level digital-to-analog converter and a 33-level flash analog-to-digital converter with digital common-mode rejection and dynamic element matching of comparator offsets. These signal-processing innovations, combined with established circuit techniques, enable state-of-the art performance in CMOS technology optimized for digital circuits     

A simple and reliable wafer-level electrical probing technique forIII-nitride light-emitting epitaxial structures

We report an easy-to-implement wafer-level electroluminescence characterization technique for InGaN/GaN light-emitting diodes (LED's) epi-wafers by means of multiple electrical probes. By first damaging the p-n junctions of the LED epilayer at localized spots, diode-like current versus voltage characteristics and emission spectra can be obtained at injection currents as high as 100 mA. This allows a relative but reliable comparison of device-related parameters such as differential quantum efficiency, leakage current, and series resistance among LED epi-wafers     

Influence of Water Vapor on the Response of Mg-Doped SrTio3 Ceramic Oxygen Sensors

Mg-doped SrTio₃ thick film sensors fabricated by screen-printing proved to be very promising for the use as oxygen sensors. A study of the influence of water on the response of these sensors gives an important basis for understanding their behavior in practical applications. The influence of water on the sensor response was measured in the oxygen partial pressure region from air (0.21 bar) to pure N₂ (2.5 × 10^–5)and the temperature range from 600 to 800°C. The relative humidity was varied from 1 to 95% RH. The resistance variation as a function of temperature and the activation energy were evaluated under different dry and wet conditions. The results obtained show that the resistance of these sensors generally decreases with increasing water content in the carrier gas and that the effect of water was strongest at lower temperatures as well as at lower oxygen pressures. To explain this behavior, it is proposed that a partial proton conduction is introduced in the water-containing atmospheres and that this contributes to the total conductivity leading to a reduction of the total resistance. Finally, the measurements also show that the response of these sensors still depends on the oxygen partial pressure according to the standard expression even in the presence of water vapor. Therefore, these sensors can still be used as oxygen sensors in humid atmospheres.     

A method for cognitive 3D geological voxel modelling of AEM data

Airborne electromagnetic (AEM) data have proven successful for the purpose of near-surface geological mapping and are increasingly being collected worldwide. However, conversion of data from measured resistivity to lithology is not a straightforward task. Therefore, it is still challenging to make full use of these data. Many limitations must be considered before a successful geological interpretation can be performed and a reasonable 3D geological model constructed. In this paper, we propose a method for 3D geological modelling of AEM data in which the limitations are jointly considered together with a cognitive and knowledge-driven data interpretation. The modelling is performed iteratively by using voxel modelling techniques with tools developed for this exact purpose. Based on 3D resistivity grids, the tools allow the geologist to select voxel groups that define any desirable volumetric shape in the 3D model. Recent developments in octree modelling ensure exact modelling with a limited number of voxels.