A linear functional relationship model for circular data with an application to the assessment of ocean wave measurements

This article suggests a linear functional relationship model for comparing two sets of circular data subject to unobservable errors. Unlike the corresponding and relatively well-studied model for linear data, maximum likelihood estimation for this model is very complicated and no explicit solutions are possible. Using a numerical approximation, we are able to solve the likelihood equations approximately, and to obtain good approximations to the likelihood estimates of the parameters. The quality of our estimates and the feasibility of the estimation method are illustrated via simulation. By establishing a parallel with the model for linear data, we are able to explain the various problems occurring in the process of estimation and to substantiate our numerical results. The interest in the model arose in connection with the study of ocean wave data; an application to such data is also given.     

Effects of green pruning on growth and stem shape of Eucalyptus nitens (Deane and Maiden) Maiden

An experiment was established in two high quality Eucalyptus nitens Deane and Maiden (Maiden) plantations in Tasmania. At the start of the experiment the trees were three years old and the plantations were on the point of canopy closure. Selected trees were pruned to remove 0, 50% or 70% of the lower green crown length, and each was surrounded by eight unpruned trees. The 50% treatment had no impact on height or diameter increment in the two years following treatment, but removal of 70% of the lower crown length resulted in significant decreases in both height and diameter increment. There were no changes in the height of 50%-pruned trees relative to the height of surrounding unpruned trees (relative height), and it was concluded that dominance would not be affected by this treatment. The relative height of 70%-pruned trees was less at one site, and this treatment may result in loss of dominance. Stem taper was generally unaffected by either pruning treatment. Changes in stem form were restricted to trees in the 70% pruning treatment and were only transient. It was concluded that removal of 50% of the lower green crown length is an appropriate level of pruning for the species provided that growth rates are rapid and pruning is timed to coincide with canopy closure. Since dominance was unaffected by this level of pruning, thinning at the time of pruning is unnecessary. It may be possible to minimise the impact on growth of higher levels of pruning by thinning at the time of pruning.     

Long-term study of partial arytenoidectomy with primary mucosal closure in 76 Thoroughbred racehorses (1992-2006)

REASON FOR PERFORMING STUDY: The effectiveness and best method to perform a partial arytenoidectomy in racehorses is unclear. This study was performed to evaluate the success of and complications that can occur after a unilateral partial arytenoidectomy with primary mucosal closure in Thoroughbred racehorses. HYPOTHESIS: Partial arytenoidectomy is an effective surgical procedure to return Thoroughbred racehorses, afflicted by arytenoid chondropathy or a failed laryngoplasty, to preoperative levels of performance. METHODS: Seventy-six Thoroughbred racehorses admitted to the New Bolton Centre between 1992 and 2006 were assessed. Information was obtained from the medical records about the horse, laryngeal abnormalities, surgery and other findings during hospitalisation. Racing information was evaluated relative to those independent variables by an analysis of variance with a level of significance of P<0.05. RESULTS: Arytenoid chondropathy was the presenting complaint in 54 horses and failed laryngoplasty in 22 horses. Thirteen horses (17%) underwent a second surgery for laser excision of intralaryngeal granulation tissue at the arytenoidectomy site. Seventy-three horses were discharged from the hospital and racing outcome was evaluated. Sixty horses (82%) raced after surgery and 46 horses (63%) raced 5 or more times after surgery. The median time from surgery to the first start was 6 months. The average earnings/start was not significantly different before and after surgery. There was no association between earnings after surgery and age, gender, location of lesion, type of lesion, duration of tracheal intubation or undergoing a second surgery. CONCLUSIONS AND POTENTIAL RELEVANCE: A Thoroughbred racehorse is likely to race after a unilateral partial arytenoidectomy with primary mucosal closure and return to a preoperative level of performance.     

Behavioural and physiological responses of sheep to 16 h transport and a novel environment post-transport

The effect of a novel lairage environment on the ability of sheep to recover from 16 h of transport was investigated. Sheep were transported from grass paddocks to either novel outside paddocks or inside pens, and housed groups were transported to either familiar or novel inside pens. During transport, sheep from outside paddocks lay down less than those from inside pens. In sheep transported to inside pens, those from outside paddocks spent more time lying and spent less time eating; hay and water intakes during the first 12 h post-transport were lower than those previously kept inside. There was no obvious effect of a novel environment post-transport on blood biochemistry, suggesting that the lower post-transport feed and water intakes in a novel environment did not have a significant effect on the ability of the sheep to recover from the feed and water deprivation associated with transport.     

Effects of pasteurization of colostrum on subsequent serum lactoferrin concentration and neutrophil superoxide production in calves

OBJECTIVE: To determine the effects of pasteurization of colostrum on serum lactoferrin concentration and neutrophil oxidative function by comparing values from calves given pasteurized (76 C, 15 minutes) colostrum versus calves given fresh frozen colostrum. ANIMALS: 8 Holstein bull calves were used to study the effects of pasteurization of colostrum on the absorption of lactoferrin and neutrophil oxidative burst. Three additional calves were used to study the effect of exogenous lactoferrin on neutrophil oxidative burst. METHODS: Calves were fed fresh frozen or heat pasteurized colostrum (76 C for 15 minutes) via esophageal feeder within 4 hours of birth. Neutrophils were isolated from whole blood samples. Neutrophil oxidative burst was induced by phorbol ester (300 ng/ml) stimulation of cells (1 X 10(6) cells) at 37 C. Serum lactoferrin concentrations were compared, using immunoblot analysis. Serum IgG concentrations were determined by radial immunoassay. Comparisons were made between the use of the 2 types of colostrum in calves by measuring subsequent serum IgG and lactoferrin concentrations and neutrophil superoxide production. RESULTS: Serum IgG and lactoferrin concentrations increased more in calves receiving fresh frozen colostrum. Neutrophil superoxide production was higher in neutrophils prepared from calves receiving fresh frozen colostrum. Colostral lactoferrin addition to neutrophil incubations resulted in increased oxidative burst. CONCLUSIONS AND CLINICAL RELEVANCE: Compared with calves given fresh frozen colostrum, calves given pasteurized colostrum had decreased serum IgG and lactoferrin concentrations and neutrophil superoxide production 24 hours after administration. These results suggest that pasteurizing bovine colostrum at 76 C for 15 minutes has substantial effects on passive transfer of proteins and neutrophil function.     

Evaluation of a Collagenase Generated Osteoarthritis Biomarker in Naturally Occurring Canine Cruciate Disease

Objective— To determine the clinical value of a novel osteoarthritis (OA) biomarker in detecting canine cruciate disease.
Study Design— Cross sectional clinical study.
Animals— Dogs (n=22) with cranial cruciate ligament (CCL) rupture and 12 control dogs.
Methods— Concentrations of collagenase-generated cleavage epitope of type II collagen (Col2-3/4C_{long mono}, or C2C) in serum, urine, and joint fluid were compared between a group of dogs with CCL rupture and a control group. Correlation of C2C concentrations to the clinical stage of stifle OA was also evaluated.
Results— There were no significant differences in C2C concentrations in serum, urine, and joint fluid between groups ( P >.05). Subjective scores of lameness, joint effusion, osteophytosis were significantly more severe in the CCL rupture group compared with the control group ( P <.05). There was no significant correlation of C2C concentrations with clinical stage of stifle OA ( P >.05).
Conclusion— This OA biomarker did not detect pathology associated with CCL rupture. Our results suggest that collagenase-specific degradation of type II collagen in articular cartilage may not be involved in the early stage of naturally occurring canine cruciate disease, and that pathology associated with naturally occurring CCL rupture is different from that of experimental OA model.
Clinical Relevance— C2C is not clinically useful in detecting CCL rupture in dogs.     

The severity of smouldering peat fires and damage to the forest soil

Smouldering wildfires propagate slowly through surface and subsurface organic layers of the forest ground and severely affect the soil, producing physical, chemical and biological changes. These effects are caused by the prolonged heating and the large loss of soil mass but are poorly documented in the literature. A series of smouldering experiments with boreal peat have been conducted under laboratory conditions to quantify these effects using small-scale samples. Peat samples of 100 mm by 100 mm in cross section and 50 mm in depth of different moisture were exposed to an external ignition source. Thermocouples placed throughout the sample bed measured the temperature evolution and tracked the peat ignition, intensity and spread of the smouldering front. The results show that moisture content controls peat ignition and that moisture below 125 ± 10% (in dry base) are required. The severity of the smouldering peat on the soil has been quantified in terms of temperature vs. residence time curves and mass loss. The measurements show temperatures in excess of 300 °C for residence times of 1 h leading to sterilization of the soil and mass loss in burnt layers above 90%.