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Pain management is a crucial component of feline medicine and surgery. This review critically evaluates studies using buprenorphine in cats and highlights the clinical application of the opioid in this species. The pharmacokinetic-pharmacodynamic ( PK- PD) modeling of IV buprenorphine has been best described by a combined effect compartmental/receptor association-dissociation model with negative hysteresis. Therefore, plasma concentrations of the drug are not correlated with analgesia, and clinicians should not expect to observe pain relief immediately after drug administration. In addition, a ceiling effect has not been demonstrated after administration of clinical doses of buprenorphine in cats; dosages of up to 0.04 mg/kg have been reported. The route of administration influences the onset, duration, and magnitude of antinociception and analgesia when using this drug in cats. At clinical dosages, the SC route of administration does not appear to provide adequate antinociception and analgesia whereas the buccal route has produced inconsistent results. Intravenous or IM administration at a dosage of 0.02-0.04 mg/kg is the preferred for treatment of pain in the acute setting. A literature search found 14 clinical trials evaluating buprenorphine sedation, analgesia, or both in cats. There were 22 original research studies reporting the antinociceptive effects of buprenorphine by means of thermal threshold, mechanical threshold, or both, minimal alveolar concentration, or PK- PD. Individual variability in response to buprenorphine administration has been reported, indicating that buprenorphine may not provide sufficient analgesia in some cats. Pain assessment is important when evaluating the efficacy of buprenorphine and determining whether additional analgesic treatment is needed. [ABSTRACT FROM AUTHOR]

Two types of sodium carbonate powder produced by spray drying (SD) and dry neutralization (DN) were studied for their compaction properties using a uniaxial compression tester. A comparison was also made with Persil washing powder. Dry neutralized sodium carbonate showed greater resistance to compression and also produced a weaker compact when compressed to 100 kPa. Spray-dried sodium carbonate had an absence of fine particles but compacted easily. Differential scanning calorimetry (DSC) showed that both types of powder were predominantly amorphous in nature. Moisture sorption measurements showed that both powders behaved in a similar way below 50% relative humidity (RH). However, dry neutralized sodium carbonate had a high moisture affinity above this RH. Particle structures were also examined using scanning electron microscopy, showing the heterogeneous interior of the spray-dried particles. [ABSTRACT FROM PUBLISHER]

Abstract: A finite element simulation model has been developed for a pinch gripper pressing a non-rigid materials (NRM) predicting deformations and stresses occurring within the material. Specific attention is given to the differences in response of NRMs to two types of gripper (rectangular gripper and cylindrical gripper). The influence of mesh refinement and aspect ratio of the elements has been studied. The non-linear behaviour of NRM compression has been described in the materials model used by the FE program. Experiments have been carried out to validate the FE modelling approach for a specific material sample (polyurethane (PU) foam). It is concluded that there is a good comparison between the modelling and experimental results and that model gives a reasonable prediction of what could happen in the real case. The advantages of this model are ease of construction, fast solution times and good accuracy. This research could be benefit gripper design, and provide a better understanding of grasping mechanism of robotic pinch gripper. [Copyright &y& Elsevier]

Abstract: A tactile display is a programmable device whose controlled surface is intended to be investigated by human touch, as a finger is dragged over it. It has a great number of potential applications in the field of virtual reality and elsewhere. In this research, a prototype tactile display incorporating magnetorheological (MR) fluid has been constructed and investigated. Surface force responses of the tactile display under various magnetic fields have been measured while a probe was moved across the upper (controlled) surface. The purpose of this experiment was to simulate the action of a human finger''s touch. As the applied magnetic field was varied, the sensed surface profiles changed in synchronisation with the magnet field strength. This preliminary research provides a new practical and effective way of achieving a tactile display without any moving components. [Copyright &y& Elsevier]

Abstract: Behavioural signs of pain are difficult to quantify and interpret in animals. Nociceptive threshold testing is therefore a useful method for examining the perception and processing of noxious stimuli underlying pain states. Devices were developed to measure response thresholds to quantified, ramped mechanical and thermal nociceptive stimuli applied to the leg or keel of unrestrained birds. Up to 9N mechanical force was delivered via a single round-ended 2mm pin using a pneumatic actuator at 0.4Ns−1. Heat was applied through a small copper element at 0.8°Cs−1 to a maximum of 50°C. The repeatability and reliability of threshold measures were validated using 10–12 broiler chickens (aged 49–66 days) per site and modality. Mechanical threshold, or skin and threshold temperature, were recorded over three sessions across a 36h period. Both stimulus types elicited clear, reproducible behavioural responses. Mechanical threshold means and 95% confidence intervals were 3.0 (2.8–3.2)N for keel and 2.0 (1.8–2.1)N for leg sites. Keel thermal tests gave a mean skin temperature of 39.3 (39.1–39.5)°C, and threshold of 46.8 (46.6–47.1)°C. Leg skin temperature was 35.7 (35.6–35.9)°C and threshold 42.5 (42.2–42.8)°C. Threshold measures were consistent within and across sessions and birds showed individual repeatability across tests within sessions. Individual birds’ mechanical keel thresholds were also repeatable across sessions. The apparatus gave reliable, reproducible measurements of thresholds to noxious mechanical and thermal stimuli. The range recorded was comparable with previously published nociceptor thresholds in dissected chicken nerve filament fibres, and the method appears suitable for studying nociceptive processes in broiler chickens. [Copyright &y& Elsevier]