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31.
  1. Geospatial models are used to predict the distribution of terrestrial and marine species, according to their ecological and ethological habits. The bottlenose dolphin is a cosmopolitan marine top predator, inhabiting most of the ocean, with the exception of polar and subpolar waters. This wide distribution is associated with a remarkable plasticity in ecological and behavioural habits, which makes it difficult to model and predict its distribution.
  2. This study proposes a ‘multi‐type approach’ to predict the presence and distribution of the bottlenose dolphin in the Pelagos Sanctuary, a Specially Protected Area of Mediterranean Importance located in the north‐west Mediterranean Sea. A multi‐type model based on random forest regression was developed, analysing the distribution habits of two geographical units living in the Pelagos area.
  3. When compared with a classical single‐type model, the multi‐type model performed much better in a prediction test (true skill statistics, TSS = 85% vs. 52%), confirming the value of this experimental approach. This work suggests that wild species should not be considered as one single‐type entity, as local specialization may change and shape their distribution habits.
  相似文献   
32.
Veterinary Research Communications - A 5-year-old healthy pluriparous pregnant Flat-coated Retriever bitch was monitored by ultrasound on post-ovulation days 30 and 57: no deviation from normality...  相似文献   
33.
A field experiment was carried out in Central Italy to assess the reliability of petiole sap for determining nitrogen (N) status on processing tomato. The crop was fertilized with different N rates and fertigation-irrigation frequencies. Reduced-N and nitrate-N concentrations were determined by lab analyses at 30, 42, 57, 71, and 84 days after transplanting. At each sampling date, the assessment of N nutritional status as resulted by sap test was compared with the actual plant N status as determined by nitrogen nutrition index (NNI). Results from sap test were in agreement with NNI indications for about 2/3 of crop cycle that represents the crucial time for N fertilizer management in tomato. The correlation coefficient of the two methods was, on average 0.854 and it was statistical significant in the whole sampling period. The nitrate concentration in the petiole sap provided a good agreement with laboratory analysis across the full range on N-nitrate (NO3) concentrations examined.  相似文献   
34.

Purpose

The turbid plumes generated by different types of dredges have specific behaviours and diffusion patterns. The dredging of the Oil Port of Genoa Multedo (Italy) with three different dredges (grab, backhoe and trailing suction hopper) enabled us to study: the physical and hydrodynamic characteristics of the water column of the port and the area just outside it; the characteristics of the turbid plumes; and the different responses of our optical and acoustic instruments.

Materials and methods

In the dredging operations, a vessel equipped with a vertical acoustic Doppler current profiler and a conductivity–temperature–depth probe with a turbidimeter followed the different dredges during their daily operations. Using the acoustic backscatter and turbidity data acquired during the dredging phase, we investigated the turbidity variations caused by the dredging operations to study the evolution of the plume generated by the three different dredges.

Results and discussion

The grab plume was present only on the bottom up to a distance of 50 m from the grab, while at greater distances the turbidity fell to background values. The backhoe plume was present close to the bottom at a distance of 50 m from the dredging and, in the entire water column, at distances of 50–400 and 100 m inside and outside of the port, respectively. The trailing suction hopper dredge plume extended from the surface through the entire water column at distances from the dredging of 400 and 100 m inside and outside of the port, respectively. The highest values were found close to the bottom at distances from the dredging at 50 and 30 m inside and outside of the port, respectively.

Conclusions

The choice of a combined monitoring system is a good practical solution for studying the differences between the turbid plumes created by the three dredging tools (grab, backhoe and trailing suction hopper dredge) under different hydrodynamic conditions. Furthermore, two different types of instrument should give complementary information on different aspects of sediment resuspension during a dredging operation.  相似文献   
35.
Several approaches are available to achieve multi-transgene-stacking in plants for the introduction of complex or multiple traits. We used co-transformation with multiple plasmids using particle bombardment and hybridization of plants carrying separate transgenes in wheat. In the co-transformation approach, four constructs containing the defence genes Pvpgip2, Acpmei, Taxi-III or Xip-III and the bar gene were co-bombarded into immature embryos of durum or common wheat. The four transgenes integrated into the wheat genome at co-transformation frequencies of 58 and 27 % in durum and common wheat, respectively. Segregation analysis of the T1 and T2 generations showed that 45–90 % of the progeny inherited all four transgenes together in both durum and common wheat. In the hybridization approach, pyramiding of Pvpgip2, Acpmei and Taxi-III was achieved by crossing durum wheat plants containing the Pvpgip2 and Acpmei transgenes with transgenic plants carrying Taxi-III. Segregation analysis showed that only 4.5 % of the progeny inherited all four transgenes together, including the bar gene. Co-expression analyses of Pvpgip2, Acpmei and Taxi-III or Xip-III showed loss of mRNA or protein activity in the progenies of both transgenic and hybrid wheat lines. Particle bombardment yielded progenies with either tightly linked transgenes or with different transgene combinations that could be useful in research applications. However, its efficiency was constrained by the occurrence of transgene silencing.  相似文献   
36.
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38.

Purpose  

The potential negative effects of dredging on a sensitive marine environment (e.g. phanerogamic meadows, beaches, benthic populations) can be justification for restrictions on the dredging project or the creation of a dredging monitoring plan. The dredging of the Port of Genoa (Italy) provided the opportunity to study the concentration of total suspended solids, the physical characteristics of the water column, and the winds and currents determining the hydrodynamic characteristics of the port, and to test a double monitoring system for turbidity control.  相似文献   
39.
To determine the prevalence of Anaplasma phagocytophilum in dogs in Germany serum samples from 1124 dogs that were under suspicion of having anaplasmosis were examined. The samples were tested by an indirect immunofluorescence test (OFT) for antibodies to A. phagocytophilum. The geographical origin of positive cases were analysed with an geographic information system. Antibodies to A. phagocytophilum were found in 563 (50.1%) of the tested dogs. 166 dogs came from Saarland, 161 from North Rhine-Westphalia, 134 from Baden-Wuerttemberg, 33 from Bavaria, 22 from Rhineland-Palatinate, 11 from Hamburg, 10 from Brandenburg, 9 from Lower Saxony, 8 from Hesse and Berlin respectively and 1 from Schleswig-Holstein. Clinical signs and laboratory findings of 26 seropositive dogs were analysed. Those dogs showed a low haematocrit, thrombocytopenia and leucocytoses as well as higher values for alkaline phosphatase, ALAT und bilirubin. The clinical signs were lameness in 13 dogs, lethargy in 5, and uveitis in 3 dogs. Rhinitis and lymphadenopathy was found in 2 dogs and retinal detachment with blindness in 1 dog.  相似文献   
40.
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