Spatial scan statistics using elliptic windows

The spatial scan statistic is widely used to search for clusters. This article shows that the usually applied elimination of secondary clusters as implemented in Sat Scan is sensitive to smooth changes in the shape of the clusters. We present an algorithm for generation of a set of confocal elliptic windows and propose a new way to present the information when a spatial point process is considered. This method gives smooth changes for smooth expansions of the set of clusters. A simulation study is used to show how the elliptic windows outperforms the usual circular windows. The proposed method for graphical representation of the information in a set of clusters contain more information than just presenting nonoverlapping clusters. We suggest that more than one graphical representation of a set of clusters should be used to easily extract more information and to avoid pitfalls of the selected method.     

Ex vivo bioluminescence imaging of late gestation ewes following intrauterine inoculation with lux-modified Escherichia coli

Our objectives were to develop an ovine model for Escherichia coli-induced preterm delivery, and monitor E. coli (lux modified for photonic detection) invasion of the fetal environment--ewes (124+/-18d of gestation) received intrauterine inoculations using E. coli-lux as follows: control (n = 5), 1.2 x 10(6) CFU/ml (n = 5), 5.6 x 10(6) CFU/ml (n = 5) E. coli-lux. Preterm delivery occurred between 48 and 120 h post-inoculation in 60%, 60% of ewes infected with 1.2, and 5.6 x 10(6) CFU/ml E. coli-lux, respectively, with presence of emitting bacteria confirmed by real-time imaging of lamb tissues. In summary, preterm delivery and/or fetal distress were observed in a majority of inoculated ewes. Finally, the use of photonic bacteria with imaging was a feasible means to monitor bacterial presence ex vivo.     

Hormonal profiles of late gestation ewes following intra-uterine inoculation with and without lux-modified Escherichia coli

The objectives of these investigations were to develop an ovine model for Escherichia coli (E. coli)-induced preterm delivery, and monitor ewe hormonal response. EXP 1: Ewes (105 +/- 13 days of gestation) were allotted to the following intra-uterine inoculations: Saline-(CON; n=5); 1 x 10(6) CFU/ml (Low Treatment, LT; n=6); or 1 x 10(7) CFU/ml (High Treatment, HT; n=6) E. coli. Twenty-four h after inoculation, the HT ewes had increased (P<0.05) cortisol compared to LT and CON ewes, and HT and LT ewes had increased (P<0.05) progesterone compared to CON ewes. Preterm delivery was 33% for LT ewes and 0% for HT and CON ewes. EXP 2: Ewes (124 +/- 18 days of gestation) were allotted to the following intra-uterine inoculations using lux-modified E. coli: Trial-1: Luria Broth (LB; CT1; n=5); 4.0 x 10(6) CFU (n=5), 20.0 x 10(6) CFU (n=5); and Trial-2: LB (CT2; n=5), 1.2 x 10(6) CFU (n=5), and 5.6 x 10(6) CFU (n=5) E. coli-lux. Preterm delivery occurred between 48 and 120 h post-inoculation in 60, 25, 60 and 75% of ewes infected with 1.2, 4.0, 5.6, and 20 x 10(6) CFU, respectively. Serum cortisol and progesterone did not differ (P>0.05) between CT1 or CT2 and inoculated ewes. In summary, 25 to 75% of ewes inoculated preterm delivered. However, variable results in cortisol and progesterone profiles between Control and inoculated ewes were observed between the two studies.     

Effects of swim‐with‐dolphin tourism on the behaviour of spinner dolphins,at Samadai Reef in the Egyptian Red Sea

1. Spinner dolphins, Stenella longirostris, are the primary target for marine mammal tourism in Egypt. The present study investigated the short‐term effects of tourist presence on the behaviour of spinner dolphins at Sha'ab Samadai (Samadai Reef), in the southern Egyptian Red Sea.
2. The reef has a large central lagoon where a population of spinner dolphin regularly rest from mid‐morning to mid‐afternoon; visitors are permitted to snorkel in the southern part of the lagoon, but not in the northern closed zone that the dolphins mainly use.
3. Dolphin behaviour was monitored both on days when tourist boats were present and on days when they were absent. In the presence of tourists the proportion of time that the dolphins spent resting was reduced by two‐thirds, whereas the times spent milling, travelling, and showing avoidance behaviour all increased.
4. Furthermore, upon using Markov chain modelling to investigate the effect of tourist presence on the transition probabilities between dolphin activity states, significant changes were found in 10 of the 25 possible behavioural transitions, including increased probabilities of transitioning from resting to milling or travelling, from milling to travelling or avoiding, and from travelling to avoiding.
5. These findings raise concerns that despite the management measures in place, tourist activities affect the dolphins’ behaviour to a greater extent than was previously apparent, with potential long‐term negative effects on their energy budget. The study led to proposals for amending the zoning of the site and for strengthening the regulations for tourist vessels.

     

Effect of astaxanthin and vitamin A on growth and survival during first feeding of Atlantic salmon, Salmo salar L.

Abstract. The interactions of astaxanthin and vitamin A on the growth and survival of Atlantic salmon, Salmo salar L., during the first-feeding period were examined using semi-purified diets. Alevins, with a mean initial weight of 0.18g, were fed diets supplemented with 0, 20 and 40 mg astaxanthin/kg dry diet and 0, 750 and 1500 μg vitamin A/kg dry diet for 20 weeks. The weights of the fish were recorded throughout the experimental period and carcasses were collected for proximate composition, vitamin A and astaxanthin analyses at the beginning and end of the experiment. The feeds were analysed for proximate composition, vitamin A and astaxanthin levels.
No interaction between astaxanthin and vitamin A was found in relation to the growth, survival or vitamin A content of the fry. Astaxanthin was found to strongly influence the growth, survival and vitamin A concentration in the fish. Poor growth and low survival rates were observed in groups fed diets without astaxanthin, including the group fed a diet with sufficient vitamin A. The results indicate both a provitamin A function of astaxanthin and a specific function of astaxanthin. Astaxanthin was found to be essential to alevins during the first-feeding period.     

Root development of beetroot,sweet corn and celeriac,and soil N content after incorporation of green manure

Summary

Root development in beetroot (Beta vulgaris L. ssp. vulgaris var. conditiva Alef.), sweet corn (Zea mays L. convar. Saccharata Koern.) and celeriac (Apium graveolens L. var. rapaceum Gaud.) was followed during two growing seasons with the aim of describing the root systems and nitrogen (N) utilisation of the three vegetables. The crops were grown after incorporation of green manure either in the preceding Autumn or Spring. Beetroot reached a final root depth of 1.55 – 1.8 m. For sweet corn, the final root depths were 0.6 and 0.9 m and, for celeriac, 0.45 and 0.6 m, in the two years, respectively. The simple measure of average root depth reflected the depth to which soil mineral N was depleted over the season by each of the three vegetables. Autumn incorporation of green manure resulted in higher mineral N contents in the soil layers below 0.5 m compared to a Spring incorporation. For beetroot, this resulted in 0.5 m-deeper root depths and higher root intensity below 0.5 m at harvest. This study shows large differences in root intensity between years, and in root depths between species. This knowledge can be used to improve N-use efficiency in vegetable production.     

The relationship between feed intake and gonad growth of single and stocked green sea urchin (Strongylocentrotus droebachiensis) in a raceway culture

This study provides a robust relationship between feed intake (FI), gonad growth (GG), and feed conversion ratio (FCR) of cultured adult green sea urchin Strongylocentrotus droebachiensis. Sea urchins (test diameter: ∼ 54 mm and live weight: ∼ 70 g) were collected in the wild and cultured either individually or subjected to one of three stocking densities, i.e. low 2.5 (N = 36), medium 3.7 (N = 54), or high 7.3 (N = 108) kg animal per m². Animals were fed a prepared diet in excess for 56 days at 6.5-4.5 °C. The gonad index (GI) more than doubled during the 56 day trial. The final mean values of GI (17-18%), FI (0.3-0.4 g feed per animal per day), and FCR (∼ 3 g feed per g increase in gonad weight) were statistically similar between individual and stocked animals. Based on data from the individually cultured sea urchins, the relationship between daily FI (g feed per animal) and GG (g gonad increase per animal) could be described by the equation: GG = 0.619FI − 0.097 (R² = 0.533, P < 0.001). In conclusion, marketable sizes of green sea urchin perform well in raceways at densities of 7-8 kg animal per m² without adverse effects on FI, GG, and FCR.     

Resolution of hyphaema following intracameral injection of tenecteplase in a Stock Horse

Intracameral injection of tissue plasminogen activator has been suggested as a means of hastening the clearance of blood from the anterior chamber and reducing the risk of synechia and fibrotic membrane formation in horses with hyphaema. The following report describes a case of ocular trauma in which intracameral injection of tenecteplase (TNK), a new‐generation plasminogen activator, resulted in rapid resolution of hyphaema and successful outcome. However, a large dose (1 mg) was administered and may have been associated with retinopathy and keratopathy. TNK may be an effective treatment for equine hyphaema and further controlled clinical or experimental studies are required to determine its efficacy and safety profiles.