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11.
Canine idiopathic pulmonary fibrosis is a chronic, progressive interstitial lung disease particularly prevalent in West Highland White Terriers. In the present prospective pilot study, we evaluated the feasibility of modified VetMousetrap? device in high resolution CT to detect idiopathic pulmonary fibrosis in West Highland White Terriers. Twelve awake West Highland White Terriers with canine idiopathic pulmonary fibrosis and 24 clinically healthy West Highland White Terriers were scanned using a helical dual slice scanner utilizing VetMousetrap? device without or with minimal chemical restraint with butorphanol. Three evaluators blindly assessed the images for image quality and the presence of canine idiopathic pulmonary fibrosis related imaging findings such as ground glass opacity and reticular opacities. Additionally, the attenuation of the lung was quantified with ImageJ software using histogram analysis of density over the lung fields. Computed tomography was successfully completed and motion artifact ranked in statistical analysis barely noticeable to mild in all dogs. The agreement between imaging findings and clinical status was very good with overall κ value 0.91 and percentage of agreement of 94%. There was also very good intraobserver (κrange = 0.79‐0.91) and interobserver agreement (κ = 0.94). Moderate to severe ground glass opacity was present in all affected dogs. In the ImageJ analysis, a significant difference in lung attenuation between the study groups was observed. We conclude that modified VetMousetrap? device is applicable in diagnosing canine idiopathic pulmonary fibrosis in awake West Highland White Terriers avoiding anesthetic risk in these often severely hypoxic patients.  相似文献   
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Elbow incongruity is a form of elbow dysplasia that causes osteoarthritis, pain, and lameness, and it is common in chondrodystrophic dog breeds. The objective of this retrospective secondary analysis study was to evaluate the intra‐ and interobserver repeatability of a novel radiographic incongruity grading system for assessing elbow incongruity in three chondrodystrophic dog breeds—the dachshund, Skye Terrier, and Glen of Imaal Terrier. We conducted an observer agreement study that included 220 mediolateral antebrachial radiographs from 110 dogs with the elbow in 90° flexion. The radiographs were independently assessed by three observers at three time points, using a four‐stepped grading scale. The proportion of agreement and Kappa coefficient were calculated. Both the intra‐ and interobserver proportions of agreement were substantial when three grades were required to be identical (.705‐.777 and .609, respectively), and almost perfect for two identical grades (.991‐1.000 and .991, respectively). Some differences in repeatability between breeds were noted; specifically, the intraobserver repeatability was higher in the dachshund, and the interobserver repeatability was lower in the Glen of Imaal Terrier. Our study showed that the radiographic imaging protocol and incongruity grading system have high repeatability when assessing elbow incongruity in chondrodystrophic dog breeds.  相似文献   
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Interspecific hybrids were developed between Trifolium alexandrinum cultivar Wardan × Trifolium vesiculosum and T. alexandrinum cultivar BL1 × T. vesiculosum through embryo rescue, as the crosses failed to set seed under natural conditions. Trifolium vesiculosum was used as a donor/male parent in this study as it is reported to possess tolerance to stem rot and high forage yield. Fertilization in crossed florets of the crosses was manifested from the recovery of swollen ovaries (< 7.80%) and confirmed from the presence of one degenerated ovule in most (> 93.00%) of the swollen ovaries. The hybrid embryos at various developmental stages (heart, torpedo and cotyledonary) were rescued at a frequency of 2.56% from Wardan × T. vesiculosum and 6.12% from BL1 × T. vesiculosum. Differentiation occurred only in the cotyledonary stage embryos, resulting in 17 putative interspecific hybrid plantlets. The assessment of plantlet hybridity through SSR markers (for the alleles inherited from the donor parent), micromorphological leaf traits (leaf texture and stomata) and morphological characters (plant height, leaflet length and width) confirmed production of two interspecific hybrids designated as AV1 and BV3 representing both the crosses. AV1 displayed moderate resistance and BV3 was resistant to stem rot.  相似文献   
16.
Context

Climate and land-use change have led to disturbance regimes in many ecosystems without a historical analog, leading to uncertainty about how species adapted to past conditions will respond to novel post-disturbance landscapes.

Objectives

We examined habitat selection by spotted owls in a post-fire landscape. We tested whether selection or avoidance of severely burned areas could be explained by patch size or configuration, and whether variation in selection among individuals could be explained by differences in habitat availability.

Methods

We applied mixed-effects models to GPS data from 20 spotted owls in the Sierra Nevada, California, USA, with individual owls occupying home ranges spanning a broad range of post-fire conditions after the 2014 King Fire.

Results

Individual spotted owls whose home ranges experienced less severe fire (<?5% of home range severely burned) tended to select severely burned forest, but owls avoided severely burned forest when more of their home range was affected (~ 5–40%). Owls also tended to select severe fire patches that were smaller in size and more complex in shape, and rarely traveled?>?100-m into severe fire patches. Spotted owls avoided areas that had experienced post-fire salvage logging but the interpretation of this effect was nuanced. Owls also avoided areas that were classified as open and/or young forest prior to the fire.

Conclusions

Our results support the hypothesis that spotted owls are adapted to historical fire regimes characterized by small severe fire patches in this region. Shifts in disturbance regimes that produce novel landscape patterns characterized by large, homogeneous patches of high-severity fire may negatively affect this species.

  相似文献   
17.
Palang  Hannes  Külvik  Mart  Printsmann  Anu  Storie  Joanna T. 《Landscape Ecology》2019,34(7):1807-1823
Context

Two approaches to study landscape change have been exploited: one that tries to study the developments that have happened in the past, and another that tries to foresee future.

Objectives

We analyse how this dual approach can help understanding landscape change, how people relate to it in general, what their expectations and preferences are. We also discuss the usefulness of path dependency theory, cultural sustainability, and cultural ecosystem services approaches in understanding the management of a historical cultural landscape.

Methods

First, we revisit a 1999 scenario study that outlined the possible trajectories of change prior Estonian accession to the European Union in 2004. Then, through series of studies we track the wider context of the landscape changes, analysing the results from the interviews and combining those with the visible results. We seek to answer whether or not the landscape changes that occurred followed any of the past scenarios, and if people’s preferences changed.

Results

The dynamics of realisation of different scenarios was not straightforward. However, people showed clear preference towards landscapes that carried signs of the continuation of rural life. What was not foreseen when designing the scenarios was the upsurge of local identity creating the links with the past.

Conclusions

In this Estonian traditional cultural landscape, stewardship, culture and cultural ecosystem services, or nature’s contribution to people as IPBES prefers to call this now, define what caring for the landscape involves.

  相似文献   
18.
We previously traced 10B-enriched boric acid from shoots to roots to demonstrate the translocation of boron (B) in Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings. To gain a more detailed understanding of B translocation, we sought: (1) to demonstrate B retranslocation directly, by showing that foliar-applied 10B is located in the new growth after dormancy; and (2) to assess whether shoot-applied B affects growth in the long term. We applied 10B-enriched boric acid to needles of Scots pine and Norway spruce seedlings. After a dormancy period and 9 weeks of growth, small but significant increases in the 10B isotope were found in the new stem and needles of both species. In Scots pine, the total B concentration of the new stem was also increased. Both species contained polyols, particularly pinitol and inositol. Boron-polyol complexes may provide a mechanism for mobilizing B in these species. To determine the long-term effects of applied B, seedlings were grown for two growing seasons after the application of 10B to shoots. In Norway spruce, the proportion of 10B in the root systems and current needles of the harvest year was slightly higher than in the controls, and in Scots pine root systems, marginally so. The B treatment had no effect on growth of Norway spruce seedlings. In Scots pine seedlings, the B treatment caused a 33% increase in total dry mass and significantly increased the number of side branches.  相似文献   
19.
Leaf hydraulic conductance (K(leaf)) and several characteristics of hydraulic architecture and physiology were measured during the first 10 weeks of leaf ontogeny in Populus tremula L. saplings growing under control, mild water deficit or elevated temperature conditions. During the initial 3 weeks of leaf ontogeny, most measured characteristics rapidly increased. Thereafter, a gradual decrease in K(leaf) was correlated with a decrease in leaf osmotic potential under all conditions, and with increases in leaf dry mass per area and bulk modulus of elasticity under mild water deficit and control conditions. From about Week 3 onward, K(leaf) was 33% lower in trees subjected to mild water deficit and 33% higher in trees held at an elevated temperature relative to control trees. Mild water deficit and elevated temperature treatment had significant and opposite effects on most of the other characteristics measured. The ontogenetic maximum in K(leaf) was correlated positively with the width of xylem conduits in the midrib, but negatively with the overall width of the midrib xylem, number of lateral ribs, leaf dry mass per area and bulk modulus of elasticity. The ontogenetic maximum in K(leaf) was also correlated positively with the proportion of intercellular spaces and leaf osmotic potential, but negatively with leaf thickness, volume of mesophyll cells and epidermis and number of cells per total mesophyll cell volume, the closest relationships being between leaf osmotic potential and number of cells per total mesophyll cell volume. It was concluded that differences in protoplast traits are more important than differences in xylem or parenchymal cell wall traits in determining the variability in K(leaf) among leaves growing under different environmental conditions.  相似文献   
20.
Objectives To evaluate the success rate of various surgical techniques for the management of lower eyelid entropion in cats. Design Retrospective study. Animals studied One hundred and twenty‐four cats with surgical correction of lower eyelid entropion of 200 eyes over a 13 year period. Methods Records of 124 cats were reviewed for signalment, type of entropion, surgical procedure performed and post‐operative result. Results Combinations of the Hotz‐Celsus (HC), lateral canthal closure and full thickness wedge resection techniques were used to treat 64 bilateral and 60 unilateral cases of lower lid entropion. Twenty‐three cats were under a year of age, 52 cats were aged between 2 and 8 years and 49 were over 8 years old. The overall success rate for a single surgical procedure (which may consist of multiple techniques) to correct lower eyelid entropion was 96.0% per eye. The remaining 4.0% had the entropion resolved with a second surgery. A combined HC and lateral canthal closure had a 99.21% success rate of resolving lower lid entropion. Geriatric cats were the most likely age group to develop corneal sequestra; 37% of cats in this group presented with entropion and corneal sequestra concurrently. Seventeen percent of cats that presented with unilateral entropion and did not have prophylactic surgery on the fellow eye went on to develop entropion in the fellow eye. Conclusions A combined HC and lateral canthal closure was the most effective surgical technique in managing lower eyelid entropion of cats in our study. Prophylactic lateral canthal closure in the unaffected eye is recommended.  相似文献   
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