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151.
Knowledge about spatial soil variation in terms of measured pedodiversity, as well as the spatial distribution of soils in terms of spatial subset representativity, offers the possibility to estimate the quality and variance within a soil map. Additionally, it can help to identify representative sample locations. Demonstrated at the German soil map at a scale of 1:1,000,000, this study describes a methodology to analyze the distribution of taxonomical pedodiversity using the Simpson index and a new approach to derive representative spatial subsets based on a modified χ2‐test (χm2), which can be used as monitoring areas. To analyze the spatial composition of the soil map and to detect differences in the underlying mapping schemes of the German soil map 1:1,000,000, three different spatial data structures were studied: (1) the entire soil map, (2) the soil map segmented into geomorphological regions, and (3) the soil map segmented into the Federal States of Germany. Representative patches of varying sizes were statistically derived for all spatial subsets as well as the entire soil map ranging from 20 km × 20 km up to 70 km × 70 km. The results show that the measured pedodiversity is linked to both the geomorphology as well as the political borders of the Federal States. On the one hand, this reveals the uncertainty of measuring pedodiversity on the basis of soil‐class maps as the spatial representation of pedodiversity is influenced by the different mapping traditions and methods applied in the 16 Federal States of Germany. On the other hand, it allows the analysis of the aggregation schemes of different landscapes. The presented approach helps to understand large soilscapes and to compare different soil maps of different states and countries as well as to enhance the soil map with additional information. Furthermore, the representative patches can be used to select soil‐monitoring areas.  相似文献   
152.
Agricultural encroachment into low-governance forest frontiers including vast tracts of hitherto unclaimed public lands and indigenous territories represents one of the most abrupt land-use transitions in tropical countries. This often results from spontaneous migration from more heavily-settled regions or direct subsidies from land redistribution programs prescribed by central-government policy. Here, we briefly review the spatial scale and environmental consequences of agrarian resettlement schemes in tropical forest countries, and explore the policy contradictions of competing government agencies in shaping conflicting rationales for either conservation or rural development. We focus on the largest tropical forest region on Earth, the Brazilian Amazon, which continues to attract one of the largest waves of land-tenured and landless migrant farmers from elsewhere in Brazil. We argue that the environmental and monetary costs associated with these resettlement schemes are rarely outweighed by the socioeconomic benefits accrued to translocated farmers. Land-use planning in lowland tropical forest regions like Amazonia would benefit from a truly integrated policy framework that bridges the divide between conflicting government sectors, particularly in relation to smallholder occupation of previously intact forest areas, which increasingly contributes with a significant fraction of deforestation in many regions.  相似文献   
153.
Seven primer pairs flanking di- and tri-nucleotide repeat sequences, identified from previously sequenced regions of the potato genome, were examined for their potential use in DNA-fingerprinting of thirty-nineSolanum tuberosum subsp. tuberosum cultivars (released between 1861 and 1988) and one diploidS. phureja breeding line. Of the simple sequence repeats (SSRs), the primers for six SSRs amplified DNA sequences within the potato genome between cultivars for a total of 14 bands. The polymerase chain reaction (PCR)based amplification products generated from each primer pair consisted of 1 to 2 bands per cultivar but band variation among cultivars demonstrated up to 4 bands per SSR. A similarity matrix generated from five SSRs was able to distinguish 24 of the 40 cultivars. However, when the potato cultivars were grouped by tuber type (round white-skinned, long white-skinned, russetskinned, red-skinned, and yellow flesh) only five pairs of cultivars remained indistinguishable: Atlantic/Katahdin, Belchip/Wauseon, Red LaSoda/Bliss Triumph, Red Pontiac/Norland, and Burbank/Spunta. Although SSRs did not generate unique fingerprints for all of the North American genotypes examined, the potential to discriminate most cultivars should increase as additional SSRs are identified in potato.  相似文献   
154.
The hypothesis of the present study was that a GnRH agonist application at early pregnancy would alter the pattern of the key reproductive hormones LH and FSH, and subsequently that of estradiol (E2) and especially progesterone (P4), and improve the conditions for embryo survival in early pregnant gilts. Therefore, the endocrine effects of a GnRH agonist (GnRHa) application to gilts (n=11 GnRHa treated, n=9 saline Controls) were studied in blood samples from the Vena cava caudalis. GnRHa injected on Day 12 after insemination induced elevated (P<0.01) LH and FSH levels for at least 180 min. However, subsequent LH concentrations were not altered up to Day 21 of pregnancy. LH pulse number, estimated in 6-h period samples on Days 13, 15 and 17, was not influenced by treatment and pregnancy. LH pulse amplitude was decreased (P<0.05) on Days 13 to 17 in pregnant gilts of both groups, but not in nonpregnant animals. In pregnant GnRHa-treated gilts, the basal LH level was elevated compared with the Controls (P<0.01). Additionally, differences (P<0.05) in basal LH were present between the pregnant and nonpregnant animals. The P4 and E2 secretion pattern was not affected by GnRHa. P4 concentrations increased (P<0.01) from Day 10 to Day 14 regardless of the treatment. P4 revealed a pulse-like pattern, but without a definite relation to the LH pulse characteristics. Also, pregnancy rate (73 vs. 67%) and the number of fetuses (12.8 ± 2.3 vs. 11.6 ± 2.3) were unaffected in the treated and Control gilts, respectively. The present study did not confirm the initial hypothesis that a GnRHa-mediated LH effect could alter ovarian steroid secretion and favorably support early embryo development and pregnancy outcome.  相似文献   
155.
Post anaesthetic myelopathy is a rare but devastating complication of equine anaesthesia and there is a need for better understanding of the condition and to raise veterinary awareness. The aim of this study was to collect data on unreported cases and combine those with reported cases to better identify possible risk factors and early clinical signs and outcomes of horses developing post anaesthetic myelopathy (PAM). A survey was conducted to identify cases of equine PAM. Records were also requested via the American College of Veterinary Anaesthesiologists listserve. Additional cases of PAM were located through review of the literature. Eighteen new cases and 12 published cases were identified. Large‐framed breeds between 6–24 months of age were more commonly affected (23/30). The majority of horses were positioned in dorsal recumbency during anaesthesia. Lack of movement and deep pain of the rear limbs, loss of anal tone and lack of panniculus response from the mid to caudal thorax distally were the most common clinical findings. Reported treatments resulted in no improvement of clinical signs and all horses died or were subjected to euthanasia from a few hours to 8 days post operatively. Poliomyelomalacia of the caudal spinal cord is the most common histopathological finding. Although a rare complication it is a catastrophic risk that can be eliminated by performing a standing operation. Hopefully in the future better understanding of this condition will lead to prevention and treatment strategies.  相似文献   
156.
157.
The primary objective of this study was to determine if certain behavior traits were genetically correlated with reproduction. If 1 or both of the behavior traits were found to be correlated, a secondary objective was to determine if the behavior traits could be useful in selecting for more productive females. A scale activity score taken at 5 mo of age and a farrowing disposition score taken at farrowing were selected as the behavioral traits. Scale activity score ranged from 1 to 5 and farrowing disposition ranged from 1 to 3. Reproductive traits included age at puberty, number born alive, number born dead, litter birth weight, average piglet birth weight, number weaned, litter weaning weight, average weaning weight, wean-to-estrus interval, ovulation rate including gilts, and postweaning ovulation rate. Genetic correlations between scale activity score and reproduction ranged from -0.79 to 0.61. Three of the correlations, number born alive (P < 0.01), average piglet birth weight (P < 0.001), and wean-to-estrus interval (P = 0.014), were statistically significant but included both favorable and antagonistic correlations. In contrast, all but 1 of the farrowing disposition correlations was favorable and ranged from -0.66 to 0.67. Although only the correlation with litter birth weight was significant (P = 0.018), the consistent favorable direction of all farrowing disposition correlations, except average weaning weight, shows a potential for inclusion of farrowing disposition into a selection program.  相似文献   
158.
Hylocereus (Berger) Britton et Rose, Selenicereus (Berger) Britton et Rose and Epiphyllum Haw. species have commercial potential as exotic fruit crops in semi-arid and arid lands. The high genetic variability among these species offers an opportunity for commercial cultivation. Toward this end we investigated genomic and morphological characteristics including: nuclear DNA content (2C-values), stomatal length and density, potential yield and reproductive parameters in 64 Hylocereus, Selenicereus and Epiphyllum accessions. Nuclear DNA content ranged from 3.21 pg for S. grandiflorus (L.) Britton et Rose spp. grandiflorus to 8.77 pg for H. megalanthus (Vaup.) Bauer. All species were diploid except the tetraploids H. megalanthus and S. vagans (Bgek.) Britton et Rose. Stomatal length and density, fruit weight, potential yields, number of viable seeds per fruit and fruit maturation times were highly variable among accessions. No significant correlations were found between stomatal length, density, and nuclear DNA content, nor between fruit weight and seed number. The high genetic variability found between the accessions here provides further support for the excellent prospects of conserving and domesticating these exotic species.  相似文献   
159.
160.
A captive adult female bottlenose dolphin presented with stillbirth. The placenta appeared oedematous. No other gross lesions were evident in the placenta or the stillborn calf. Histopathology revealed mild multifocal placentitis and foetal encephalitis. Brucella sp. was isolated from lung, liver, spleen and kidney. Sequence and phylogenetic analysis demonstrated this organism to be most similar to Brucella ceti sequence type (ST) 27. Brucella sp. DNA was detected in formalin-fixed paraffin-embedded placenta and brain by real-time PCR using primers targeting the IS711 gene. Immunohistochemical staining revealed Brucella sp. antigen in placental inflammation. This is the first report of isolation of Brucella sp. from a marine mammal in the Southern Hemisphere and the first report of marine Brucella-associated disease in Australia.  相似文献   
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