Nosebands are used by riders to prevent the horse from opening its mouth, to increase control and, in some cases, to comply with the competition rules. While equestrian texts traditionally recommend that two adult human fingers should be able to fit under a fastened noseband, noseband tightness levels are not, in general, regulated in competition. Possible detrimental consequences for the horse, of excessively tight nosebands, include discomfort, pain or tissue damage. The current study investigated noseband usage in equestrian competition. Data regarding noseband type, position, width and tightness were collected from 750 horses in eventing (n = 354), dressage (n = 334) and performance hunter (n = 62) competitions in Ireland, England and Belgium. Data were collected immediately before or after the performance. Using the ISES taper gauge as a guide, results were classified according to the number of ‘fingers’ that could fit under the noseband at the nasal planum, and assigned to six groups: greater than 2 fingers; 2 fingers; 1.5 fingers; 1 finger; 0.5 fingers; zero fingers. A calliper was used to measure noseband width and position relative to the facial crest. The data were not normally distributed so Kruskall-Wallis and Mann-Whitney tests were used. In all, 44% of horses fell into the zero fingers classification while only 7% were in the two fingers classification. Significant differences emerged between disciplines (p<0.001), with the highest levels of noseband tightness measured among eventers followed by dressage horses with lowest levels among performance hunters. Noseband tightness did not differ significantly with horse age (p>0.05), which ranged from 4 to 19 years. The flash noseband was the most commonly used noseband (n = 326) and was significantly tighter than the cavesson (p < 0.001), drop noseband (p < 0.001) and the Micklem (p < 0.005). Noseband width ranged from 10 to 50 mm. Noseband position varied widely with the distance between the facial crest and upper noseband margin ranging from 0 to 70 mm. The high proportion of very tight nosebands found in this study raises concerns regarding the short and long term behavioural and physiological consequences of such tight nosebands are for the horse. Although these data are currently lacking, the findings are of concern.

Here, we present experimental evidence of the direct piezoelectric effect in the globular protein, lysozyme. Piezoelectric materials are employed in many actuating and sensing applications because they can convert mechanical energy into electrical energy and vice versa. Although originally studied in inorganic materials, several biological materials including amino acids and bone, also exhibit piezoelectricity. The exact mechanisms supporting biological piezoelectricity are not known, nor is it known whether biological piezoelectricity conforms strictly to the criteria of classical piezoelectricity. The observation of piezoelectricity in protein crystals presented here links biological piezoelectricity with the classical theory of piezoelectricity. We quantify the direct piezoelectric effect in monoclinic and tetragonal aggregate films of lysozyme using conventional techniques based on the Berlincourt Method. The largest piezoelectric effect measured in a crystalline aggregate film of lysozyme was approximately 6.5 pC N−1. These findings raise fundamental questions as to the possible physiological significance of piezoelectricity in lysozyme and the potential for technical applications.

Noseband tightness is difficult to assess in horses participating in equestrian sports such as dressage, show jumping and three-day-eventing. There is growing concern that nosebands are commonly tightened to such an extent as to restrict normal equine behaviour and possibly cause injury. In the absence of a clear agreed definition of noseband tightness, a simple model of the equine nose-noseband interface environment was developed in order to guide further studies in this area. The normal force component of the noseband tensile force was identified as the key contributor to sub-noseband tissue compression. The model was used to inform the design of a digital tightness gauge which could reliably measure the normal force component of the noseband tensile force. A digital tightness gauge was developed to measure this parameter under nosebands fitted to bridled horses. Results are presented for field tests using two prototype designs. Prototype version three was used in field trial 1 (n = 15, frontal nasal plane sub-noseband site). Results of this trial were used to develop an ergonomically designed prototype, version 4, which was tested in a second field trial (n = 12, frontal nasal plane and lateral sub-noseband site). Nosebands were set to three tightness settings in each trial as judged by a single rater using an International Society for Equitation Science (ISES) taper gauge. Normal forces in the range 7–95 N were recorded at the frontal nasal plane while a lower range 1–28 N was found at the lateral site for the taper gauge range used in the trials. The digital tightness gauge was found to be simple to use, reliable, and safe and its use did not agitate the animals in any discernable way. A simple six point tightness scale is suggested to aid regulation implementation and the control of noseband tightness using normal force measurement as the objective tightness discriminant.

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Elastomers are of interest for use as deformation elements in pressure and force sensors. In this paper, a custom designed programmable elastomer test rig (PETR) developed in order to allow the routine mechanical evaluation (compression mode) of small elastomer structures (0.3-30 mm thick) is described and characterized. The mechanical properties of two polyurethane and two silicone rubbers were investigated using the PETR. Silastic silicone (Dow Corning 9161) was found to display relatively low hysteresis and good elasticity. More in-depth investigation of this material revealed that the elastic modulus and the hysteresis were independent of the amount of catalyst used in its preparation over the range 2-6% (w/w). The Zener model was found to provide a good representation of the actual stress-strain behaviour of test specimens subjected to load-unload tests at strain rates in the range 1.25-60% min −1 (load rates 4-200 N min −1 ) and dynamic tests at frequencies in the range 0.001-0.1 Hz. The combined hysteresis and creep for a 1 h test period was not greater than 4%, with the creep contribution being up to 2.3% and occurring in a manner predicted by the Zener model. Specimen form-factor strongly influenced both the elastic modulus and the hysteresis. Increasing the form-factor from 0.5 to 2.6 increased the elastic modulus from about 3.0 to 7.6 MPa while also increasing the hysteresis from 2.4% to 25.2%.