Automated detection and tracking of marine mammals: A novel sonar tool for monitoring effects of marine industry     

Gordon D. Hastie  Gi‐Mick Wu  Simon Moss  Pauline Jepp  Jamie MacAulay  Arthur Lee  Carol E. Sparling  Clair Evers  Douglas Gillespie 《水产资源保护:海洋与淡水生态系统》2019,29(Z1):119-130

Coupling of dry matter and nutrient accumulation in forage grass     

A. R. Overma  G. W. Evers  S. R. Wilkinson 《Journal of plant nutrition》2013,36(12):2629-2642

Abstract

The logistic model has proven very useful in relating dry matter production of forage grasses to applied nitrogen. A recent extension of the model coupled dry matter and plant ? accumulation through a common response coefficient c. The objective of this analysis was to establish the validity of the extended model for each of the three major nutrients (?, ?, ?), with a common coefficient c between dry matter and each applied nutrient. Analysis of variance established the validity of this hypothesis. The model accurately described response of dry matter, plant nutrient removal, and plant nutrient concentration to applied nutrient, with overall correlation coefficients of 0.9928, 0.9972, and 0.9975 for applied N, P, and K, respectively. Furthermore, the model closely described the relationship between yield and plant nutrient removal, as well as between plant nutrient concentration and plant nutrient removal, for each nutrient. This work confirmed earlier results for applied ? with various grasses and established the validity of the model for applied ? and ? for the first time. The logistic equation is well‐behaved and simple to use on a pocket calculator. It can be used to describe yields and nutrient removal in evaluation of agricultural production and environmental quality.  相似文献   

Zur Ausbreitung von Streusalzschäden im Innern von Waldbeständen     

F. H. Evers 《European Journal of Forest Research》1976,95(1):251-264

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Predicting depth translocation of base cations after forest liming: results from long-term experiments     

Anja Guckland  Bernd Ahrends  Uwe Paar  Inge Dammann  Jan Evers  Karl Josef Meiwes  Egbert Sch?nfelder  Thomas Ullrich  Michael Mindrup  Nils K?nig  Johannes Eichhorn 《European Journal of Forest Research》2012,131(6):1869-1887

Forest liming is a common measure to counteract soil acidification. In forest practice, lime is applied to the forest floor where it changes the chemical properties. However, little is known about the depth impact of liming and the depth translocation of lime components. To investigate the long-term impact of forest liming, several study plots have been established in the 1980s in Germany in stands with different site conditions. We analysed soil chemical data obtained during the last 28?years from 45 of the study plots. We examined the depth impact of liming and predicted the main factors responsible for the increase in Calcium (Ca) and Magnesium (Mg) stocks after liming in the mineral soil using multiple linear regression analyses (MLR). Stocks of Ca and Mg as well as base saturation (BS) showed a strong depth gradient with significant differences between limed and control plots down to 40?cm of the mineral soil. About 65–70?% of applied Ca and Mg were recovered in the forest floor and the upper 40?cm of the mineral soil. BS in 0–40?cm increased by a mean of 11?%. MLR models could explain 48–74?% of the variation in mean changes of Ca and Mg in 0–10, 10–20 and 20–40?cm soil depth when soil and climate variables, amount of applied lime and years after liming are included in the model. After testing the model robustness with a cross-validating procedure, we concluded that these models might be applied to many regions in Central Europe with comparable soil and climate conditions and thus, have widespread application.  相似文献   

Black-point of grain in spring wheats of the 1978 han'est     

J.E. King    A. D. Evers  B. A. Stewart 《Plant pathology》1981,30(1):51-53

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A neurological locomotor disorder in sheep grazing Stachys arvensis     

Philbey AW  Hawker AM  Evers JV 《Australian veterinary journal》2001,79(6):427-430

OBJECTIVE: To describe the clinical signs and pathology of a neurological locomotor disorder in sheep associated with ingestion of Stachys arvensis. DESIGN: Field observations and laboratory examinations. PROCEDURE: Clinical and pathological examinations were performed on sheep with suspected S arvensis intoxication. FIELD OBSERVATIONS: Merino sheep in a flock on the southwestern slopes of New South Wales developed a neurological disorder after grazing S arvensis. Affected animals had pelvic limb paresis and a proprioceptive deficit. When forced to exercise they stumbled and collapsed. Recovery following removal from the plant was slow. Many deaths were associated with the outbreak. RESULTS: Affected sheep developed a mild degenerative myelopathy and peripheral neuropathy. Deficiencies of vitamins A and E were also observed in the affected flock. CONCLUSION: Grazing S arvensis is sometimes associated with a neurological locomotor disorder in sheep.  相似文献   

Use of 51-Cr2O3 and TiO2 as markers for the determination of passage rate and protein digestibility in rats     

K Krawielitzki  R Schadereit  E Borgmann  B Evers 《Archives of Animal Nutrition》1987,37(12):1085-1099

In a tripartite experiment with five rats each the suitability of 51Cr2O3 and TiO2 as markers was tested for estimating the transit time and passage rate as well as the total protein digestibility and the proportion of endogenous nitrogen in the small intestine with very small samples. Both markers are suited for these tests because of their simple analysis, their high recovery rate (94...105% for 51Cr2O3; 98...105% for TiO2) and their quantitative excretion in faeces within 3 days. Depending on the level of crude fibre (5.1 resp. 9.4% of DM) the transit time was found to be 7...8 h for a commercial breeding feed and 5...6 h for this commercial feed +15% straw meal. After the application of a single doses, the marker excretion of 50% appeared within 10 +/- 1 h resp. 8 +/- 1 h, and after the 12th hour there were no significant differences at all. The apparent N-digestibilities estimated by the conventional or the 51Cr2O3 resp. TiO2 indicator method did not show any differences. The proportion of endogenous nitrogen at the end of the small intestine calculated on the basis of the indicator dilution method was 83 +/- 11% for 51Cr2O3 and 83 +/- 12% for TiO2.  相似文献   

Tracheal adenocarcinoma in two domestic shorthaired cats     

P. Evers  H. R. Sukhiani  G. Sumner-Smith  A. G. Binnington 《The Journal of small animal practice》1994,35(4):217-220

The occurrence of primary endotracheal adenocarcinoma in two 12-year-old cats is reported. Dyspnoea was the most dominant clinical sign in both cases. The endotracheal masses were identified radiographically and removed via thoracotomy and tracheotomy in the first case and cervical tracheal resection and anastomosis in the second case. In both cases, the diagnosis of adenocarcinoma was confirmed histopathologically.  相似文献   

Predicted quantitative effect of logistic slaughter on microbial prevalence     

Evers EG 《Preventive veterinary medicine》2004,65(1-2):31-46

Logistic slaughter is an intervention measure intended to reduce cross-contamination during slaughter by slaughtering contaminated units (=(groups of) animals) last. This paper describes a simple mathematical model which predicts the prevalences of contaminated units after logistic and random-order slaughter. The effect of logistic slaughter is the difference between these prevalences. The model assumes that uncontaminated units can become contaminated by contaminated units that were slaughtered before them; the contributions of contaminated units are independent. It also assumes that a slaughterhouse is uncontaminated at the start of the day and that a unit that is contaminated before slaughter also is contaminated after slaughter. The model was analysed using numerical simulations; for a selection of cases, analytical formulas can be derived and are presented. Contamination of broiler flocks with Salmonella was used as a case study. Even for this simple model, data availability is a problem leading to uncertain parameter estimates. An average cross-contamination scenario predicts that the beneficial effect of logistic slaughter is as low as 9.1%, which casts doubt on its usefulness as an intervention measure. The case study produced these general model results: the effect of logistic slaughter increases with the probability of cross-contamination between units; with the length of the slaughter queue; and with sensitivity (the probability of a positive test from a unit contaminated at the start of slaughter). However, the effect is small if the prevalence of contaminated units before slaughter is low or high.  相似文献   

A Stringent and Broad Screen of Solanum spp. tolerance Against Erwinia Bacteria Using a Petiole Test     

Hendrik Rietman  Richard Finkers  Luuk Evers  Patricia S. van der Zouwen  Jan M. van der Wolf  Richard G. F. Visser 《American Journal of Potato Research》2014,91(2):204-214

Blackleg and stem rot caused by coliform bacteria belonging to Dickeya spp. and Pectobacterium spp. (both referred to as Erwinia in this paper) are a problem for potato growers worldwide and no sources of high tolerance are currently present in the cultivated S. tuberosum gene pool. To find sources of tolerance, 532 genotypes from 340 accessions, covering most of the known potato species, were assayed with P. wasabiae, P. carotovorum and D. ‘solani’ species in a petiole test. This petiole test was optimized later on using well responding genotypes from the broad screen. Based on the obtained data, the best developmental stage for cell wall degradation tests was identified to be the 4th-6th youngest leaf. Under the stringent biotic and climatic screening conditions used, only three genotypes were regarded as tolerant against all tested Erwinia species. These genotypes all belonged to the series Yungasensa, this series can be readily crossed with cultivated potato and is considered as a genetic source to upgrade the Erwinia tolerance level of cultivated potato.  相似文献