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91.
Churchward CP Hlúšek M Nicholas RA Ayling RD McAuliffe L 《Veterinary microbiology》2012,159(1-2):257-259
Mycoplasma mycoides subspecies mycoides small colony is the aetiological agent of contagious bovine pleuropneumonia, a cattle disease endemic to areas of sub-Saharan Africa. Twenty isolates from various geographical locations and the type strain were analysed by multi-locus sequence analysis (MLSA). The data generated was then used to develop three PCR primer sets to differentiate these isolates. The PCRs differentiated the isolates into four groups; the type strain (T); isolates of European origin (Eu); isolates from Tanzania (Af1) with a final group consisting of isolates from Namibia and Botswana (Af2). These PCRs offers a rapid and efficient post-identification typing method without the need to sequence and analyse multiple genes. 相似文献
92.
Miloš Ivković Washington Gapare Harry Wu Sergio Espinoza Philippe Rozenberg 《Annals of Forest Science》2013,70(5):525-534
? Context
The correlation between tree ring width and density and short-term climate fluctuations may be a useful tool for predicting response of wood formation process to long-term climate change.? Aims
This study examined these correlations for different radiata pine genotypes and aimed at detecting potential genotype by climate interactions.? Methods
Four data sets comprising ring width and density of half- and full-sib radiata pine families were used. Correlations with climate variables were examined, after the extraction of the effect of cambial age.? Results
Cambial age explained the highest proportion of the ring to ring variation in all variables. Calendar year and year by family interaction explained a smaller but significant proportion of the variation. Rainfall had a positive correlation with ring width and, depending on test site, either a negative or positive correlation with ring density. Correlations between temperature during growing season and ring density were generally negative.? Conclusion
Climate variables that influence ring width and wood density can be identified from ring profiles, after removing the cambial age effect. Families can be selected that consistently show desirable response to climate features expected to become prevalent as a result of climate change. 相似文献93.
Darius Danusevičius Jurata Buchovska Vidmantas Stanys Juratė Bronė Šikšnianienė Virgilijus Baliuckas Gediminas Brazaitis 《European Journal of Forest Research》2013,132(1):137-150
The aim of this study was to elucidate the introduction history of P. mugo in the unique landscape of the Lithuanian seaside spit of Kursiu Nerija by assessing its genetic structure and the genetic diversity. The individuals were sampled in 12 populations within an area of 3 km × 50 km along the Lithuanian part of Kursiu Nerija. P. mugo was introduced over 200 years ago to prevent sand erosion by establishing a forest cover. Chloroplast DNA polymorphism of 220 individuals of P. mugo together with 18 P. sylvestris and 11 putative P. sylvestris × P. mugo hybrids was assessed by the aid of five microsatellite markers. The standard intra-population diversity indexes were calculated. The intra-specific variation between distinct morphotypes as well as the population differentiation within the most spread P. mugo ssp. rotundata morphotype was assessed based on the haplotype frequencies by hierarchical AMOVA, GST/RST test, UPGMA clustering and PCA methods. The genetic diversity of P. mugo in Kursiu Nerija was high (He = 0.95; 83 different haplotypes). All except one of the P. mugo populations sampled contained a notable share of private haplotypes. AMOVA revealed high intra-specific diversity but low differentiation between the P. mugo populations. Most of the haplotypic variance was within populations. The UPGMA clustering produced groups more corresponding to the sub-species morphotypes than the geography of the populations. There was no geographical pattern of reduction in genetic diversity towards the younger plantations. A strong candidate for a species-specific DNA marker was found. After several events of introduction, the genetic diversity of P. mugo in Kursiu Nerija is very high and is structured based on the sub-species morphotypes rather than geography. The high frequency of shared and notable frequency of private haplotypes in most of the populations indicate that the major part of the P. mugo material originates from a number of geographically and genetically related sources, which more likely are introductions from abroad that the local collections. The high frequency of private haplotypes in the northernmost populations leaves a possibility for minor introductions from other genetically distinct sources. The absence of private haplotypes in one of the sampled populations indicates the use of local seed collections. The large number of shared haplotypes provides a strong evidence for a geneflow among the P. mugo taxa. 相似文献
94.
Dušan Jankov Dušanka Inđić Petar Kljajić Radmila Almaši Goran Andrić Slavica Vuković Mila Grahovac 《Journal of pest science》2013,86(2):211-216
The aim of the study was to investigate how various types of storage facilities with, e.g., concrete, metal, and plywood surfaces interfere with the activity of different insecticide formulations used for rice weevil Sitophilus oryzae (L.) control: malathion (EC), pirimiphos-methyl (EC), and lambda-cyhalothrin (CS and WP). Initial and residual efficacy were determined in the laboratory. Knockdown data for the initial effects were processed by probit analysis and presented as knockdown time (KDT) parameters with kdt-p lines. Delayed effects were shown as knockdown efficacy (%) determined after 24 h of weevils’ contact with 7-, 14-, 30-, 60-, 90-, 120-, 150-, and 180-day-old deposits on each surface. Malathion (EC) and pirimiphos-methyl (EC) showed the highest initial knockdown efficacy on metal, while it was 3.6 (3.4)- and 4.4 (3.3)-fold lower on concrete and plywood, respectively. Lambda-cyhalothrin (CS and WP) showed the highest initial efficacy on concrete, and slightly lower (1.3 and 2.4) fold on metal and plywood, respectively. Both formulations of lambda-cyhalothrin and malathion on metal, as well as pirimiphos-methyl on plywood were 100 % efficient against S. oryzae 180 days after the treatment. Delayed efficacy of both formulations of lambda-cyhalothrin decreased on plywood after 120 days, and after 180 days the efficacy was 55 %. All insecticides, except lambda-cyhalothrin (CS), expressed low knockdown efficacy on concrete, while the deposit of lambda-cyhalothrin (CS) on concrete was 100 % efficient during 90 days, and after 120, 150, and 180 days the efficacy was 83, 65, and 17 %, respectively. 相似文献
95.
Lunder Mojca Roškar Irena Hošek Jan Štrukelj Borut 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(1):47-53
Plant Foods for Human Nutrition - The diet rich in fruits and vegetables reduces the risk of metabolic syndrome, including diabetes development by various mechanisms of action, mainly due to the... 相似文献
96.
Branimir Jovančićević Mališa Antić Ivona Pavlović Miroslav Vrvić Vladimir Beškoski Alexander Kronimus Jan Schwarzbauer 《Water, air, and soil pollution》2008,190(1-4):299-307
This paper presents transformations of saturated hydrocarbons of petroleum type pollutants during ex situ bioremediation of soil on the pilot heap (halde), during a period of 6 months, within the grounds of Petroleum Refinery Pan?evo (Serbia). Samples for analysis were taken in time intervals of 2 weeks (P1–P12 samples). Organic substance was extracted by Soxhlet’s method and quantified. Isoprenoid aliphatics, in particular pristane and phytane, and polycyclic aliphatics of sterane and triterpane types in saturated hydrocarbon fractions were analysed by GC-MS (SIM method). Significant amounts of n-alkanes have not been detected. The MS-chromatogram revealed only marginal amounts of pristane and phytane in sample P1. Pristane and phytane occurred in sample P8, and in even higher quantities in the final sample P12. The proceeding bioremediation process was accompanied by the decrease of the relative amounts of pentacyclic terpanes of hopane type, compared to tri- and tetracyclic terpanes. In the initial sample P1 the distribution of steranes and hopanes follows a pattern, which is characteristic for crude oils. However, their identification by SIM method was not possible in samples P8 and P12 because of the reduced concentration. The observed changes in the alkane fractions’ compositions may be considered as atypical, referring to the fact that during oil biodegradation under natural conditions, decomposition of isoprenoids occurs much easier and faster than decomposition of polycyclic alkanes of tri-, tetra- and pentacyclic terpane, sterane and diasterane types, after the decomposition of n-alkanes has been almost completed. 相似文献
97.
Stable isotopes and gut contents indicate differential resource use by coexisting asp (Leuciscus aspius) and pikeperch (Sander lucioperca)
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Mojmír Vašek Antti P. Eloranta Ivana Vejříková Petr Blabolil Milan Říha Tomáš Jůza Marek Šmejkal Josef Matěna Jan Kubečka Jiří Peterka 《Ecology of Freshwater Fish》2018,27(4):1054-1065
Differential use of habitat and prey resources is an important mechanism that may allow coexistence of sympatric species. Unlike interactions between smaller cyprinid and percid fishes, the resource use by coexisting predatory asp (Leuciscus aspius) and pikeperch (Sander lucioperca) is relatively unknown. Here, gut content and stable isotope analyses were used to study ontogenetic dietary shifts and interspecific trophic niche overlap between asp and pikeperch coexisting in two reservoirs. The hypothesis that both species show an ontogenetic dietary shift from small invertebrates to large fish prey, but at the same time use different prey resources to reduce potential competitive interactions, was validated. The isotopic niches of the two predators showed no, or only a moderate, degree of overlap (0%–65%). The ontogenetic changes in the degree of interspecific isotopic niche overlap were different in the two reservoirs, suggesting that trophic segregation can be dynamic and variable among systems. Gut contents revealed that small (<100 mm standard length) asp consumed mostly terrestrial invertebrates and emerged aquatic insects, whereas small pikeperch foraged on zooplankton, larval and pupal stages of aquatic insects and fish. Larger individuals (>100 mm) of both species were predominantly piscivorous, with asp consuming more cyprinid prey and pikeperch more percid prey. Coexisting asp and pikeperch populations are able to utilise different prey resources, thereby reducing potential negative competitive interactions. 相似文献
98.
Silvia Kohutova Michaela Paninarova Miša Škorič Vladimir Jekl Zdenek Knotek Karel Hauptman 《Journal of Exotic Pet Medicine》2018,27(1):41-45
A 3-year-old, 920 g intact female guinea pig presented with a 4-month history of nonpruritic hair loss on the ventral abdomen. The physical examination revealed flank and ventral abdominal alopecia, mucoid vulvar discharge, and abdominal distension. Bilateral rounded masses just caudal to the kidneys and structures consistent with enlarged uterine horns were detected on abdominal palpation. Abdominal ultrasound revealed bilateral ovarian cysts, thickened uterine horns, and multiple circular hypoechoic and anechoic structures in the uterine wall. The patient underwent ovariohysterectomy. Gross examination of the uterus revealed a piece of hay in the left uterine horn. A final diagnosis was hormonally active ovarian follicular cysts, cystic endometrial hyperplasia, and purulent bacterial endometritis caused by Escherichia coli, Fusobacterium nucleatum, and Arthrobacter spp. Cystic endometrial hyperplasia is infrequently reported in guinea pigs, and this report describes an associated bacterial endometritis and uterine foreign body with concurrent ovarian cysts. 相似文献
99.
Fifty-six cultivars of apple were analysed for stylar ribonucleases; proteins were extracted from styles, separated by non-equilibrium
pH gel electrofocusing and stained for activity. Excellent correlation was found between the ribonuclease bands revealed and
the 11 known incompatibility, S, alleles, in 14 diploid cultivars genotyped in the classic work of Kobel by monitoring pollen
tube growth after test crossing, and in 20 cultivars genotyped, at least partially, by more recent DNA methods. For 12 triploid
cultivars studied by Kobel, the correlation was good but not perfect. Two apparent minor electrophoretic variants for S10
were noted and, to distinguish them from each other and also from the electrophoretically similar S3, isoelectric focusing
was used. Ten cultivars were genotyped for the first time. In all, 14 ribonuclease bands that may correspond to the ‘new’
S alleles, S12 to S 25, were detected but these alleles should be regarded as provisional until confirmed by pollination tests,
especially when the electrophoretic differences were only slight. Analysis of stylar ribonucleases is a convenient method
of predicting S alleles in flowering material and thereby investigating incompatibility relationships. The polymorphism of
the S locus makes it useful for checking the identity and parentage of cultivars.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
100.
F. Batič P. Kalan H. Kraigher H. Šircelj P. Simončič N. Vidergar-Gorjup B. Turk 《Water, air, and soil pollution》1999,116(1-2):377-382
Determination of the stresses operating on a forest ecosystem demands the use of several bioindication methods. Air quality indicators were assessed from an inventory of forest decline based on the assessment of tree crowns and epiphytic lichens. Photosynthetic pigments, ascorbic acid and major macronutrients were studied in Norway spruce needles as indicators of physiological and biochemical stress. Analyses were carried out on selected forest plots in polluted areas (Zasavje district, vicinity of thermal power plants) and predominantly unpolluted areas (Triglav National Park, Julian Alps, Slovenia). For some bioindication methods, there was good agreement with measured air quality and climatological parameters. The best agreement was found between total foliar sulphur in needles and epiphytic lichens, especially in more polluted areas. Agreement with forest decline inventories and analyses of some needle stress physiological/biochemical parameters was less convincing. The strength of agreement was further decreased by soil characteristics and climatic parameters, influenced also by biotic parameters and forest stand history and management. It was concluded that there is no simple bioindication method available to evaluate the vitality of a forest. 相似文献