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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Determination of bottlenecks in the production of wooden constructions

100%
Krajcovicova M.
Drewno. Prace Naukowe. Doniesienia. Komunikaty
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2011
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tom 54
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nr 186
Every production process has issues to deal with. One of these problems is the issue of bottlenecks. It is possible to reveal them through the use of optimising models that are inseparable parts of every production process these days. This article discusses the revelation of these problems during the production process. As an example we have used the production of wooden constructions. It is possible to use mathematical models, which were produced and applied in MATHEMATICS 5 program, for the revelation of bottlenecks as well as for subsequent production planning with a view to avoiding their formation.
2
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Produktionsoutput versus Ausbeute Eine analytische Herangehensweise an die Sägewerksorganisation

84%
Hermas H., Krzosek S.
Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology
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2020
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tom 109
3

Admixture promotes genetic variation in bottlenecked moose populations in eastern Poland

84%
Swislocka M., Czajkowska M., Duda N., Ratkiewicz M.
Acta Theriologica
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2015
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tom 60
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nr 2
Human activity has led to severe bottlenecks in many wildlife species in the recent past. This usually increases the strength of genetic drift, leading to loss of genetic variation. Gene flow may however counteract the genetic consequences of small population size. Using 11 of 38 tested microsatellite loci and five moose populations in eastern Poland, we investigated the effects of two phenomena: bottlenecks that occurred in the nineteenth century and the first half of twentieth century, and admixture after moose populations expanded demographically and spatially in eastern Poland after the Second World War. The statistical tests indicated a recent bottleneck in all the studied samples with respect to H E and low Garza–Williamson index values. The Biebrza population, which consists of autochthonous moose representing a branch of the Central Europe mitochondrial DNA (mtDNA) clade and immigrants belonging to the Ural clade, is one of the most variable populations of this species. AMOVA, PCA, and STRUCTURE analyses all revealed significant population structuring, with most probable existence of K = 2 genetically distinct clusters that exhibited a relatively high level of admixture. Analysis of recent dispersal rates demonstrated that population from the Biebrza Valley may supply individuals to the other four studied moose populations. We also found female-biased sex ratio in nonharvested moose populations inhabiting eastern Poland.
4

Phylogenetic relationships among the European and American bison and seven cattle breeds reconstructed using the BovineSNP50 Illumina Genotyping BeadChip

67%
Pertoldi C., Tokarska M., Wojcik J. M., Kawalko A., Randi E., Kristensen T. N., Loeschcke V., Coltman D., Wilson G. A., Gregersen V. R., Bendixen C.
Acta Theriologica
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2010
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tom 55
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nr 2
97-108
Here we present the first attempt to use the BovineSNP50 Illumina Genotyping BeadChip for genome-wide screening of European bison Bison bonasus bonasus (EB), two subspecies of American bison: the plains bison Bison bison bison (PB), the wood bison Bison bison athabascae (WB) and seven cattle Bos taurus breeds. Our aims were to (1) reconstruct their evolutionary relationships, (2) detect any genetic signature of past bottlenecks and to quantify the consequences of bottlenecks on the genetic distances amongst bison subspecies and cattle, and (3) detect loci under positive or stabilizing selection. A Bayesian clustering procedure (STRUCTURE) detected ten genetically distinct clusters, with separation among all seven cattle breeds and European and American bison, but no separation between plain and wood bison. A linkage disequilibrium based program (LDNE) was used to estimate the effective population size (N e) for the cattle breeds; N e was generally low, relative to the census size of the breeds (cattle breeds: mean N e = 299.5, min N e = 18.1, max N e = 755.0). BOTTLENECK 1.2 detected signs of population bottlenecks in EB, PB and WB populations (sign test and standardized sign test: p = 0.0001). Evidence for loci under selection was found in cattle but not in bison. All extant wild populations of bison have shown to have survived severe bottlenecks, which has likely had large effects on genetic diversity within and differentiation among groups.
5

Depauperated gene pools in Marmota m. marmota are caused by an ancient bottleneck: electrophoretic analysis of wild populations from Austria and Switzerland

67%
Preleuthner M., Pinsker W.
Acta Theriologica. Supplement
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1993
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tom 38
|
nr 2
Samples from 15 populations of the Alpine marmot Marmota m. marmota (Linnaeus, 1758) were surveyed electrophoretically for allozyme variation. Only 2 out of 50 enzyme loci showed polymorphism. Average heterozygosity was found to be low with 1.2%. No rare alleles were detected among the 8430 genes examined. The geographic variation at the two polymorphic loci (Pep-1 and Sod-1) was analysed in more detail. The distribution pattern of the allele frequencies indicates genetic differentiation between autochthonous and introduced populations. No striking deviations of the genotype distributions from Hardy-Weinberg equilibrium were observed. Thus the population structure is apparently not affected by inbreeding. The obviously diminished genetic variation and the geographic pattern of the allele frequencies at the two variable loci can be best explained by assuming a severe bottleneck in the recent past.
6

Effects of fragmentation and isolation on genetic variability of the Italian populations of wolf Canis lupus and brown bear Ursus arctos

59%
Randi E.
Acta Theriologica. Supplement
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1993
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tom 38
|
nr 2
During the last centuries many West European populations of wolf Canis lupus Linnaeus, 1758 and brown bear Ursus arctos Linnaeus, 1758 have been extirpated from most of their former ranges. Isolated populations of wolves (about 300 - 400 animals) and brown bears (about 80 - 100 animals) actually survive in the Italian Apennines, while very few (5 - 10) brown bears remain in the Italian eastern Alps. We have investigated the consequences of isolation, demographic decline, and random drift on genetic variability of the Italian populations of wolf and brown bear using restriction site analysis and nucleotide sequencing of portions of the mitochondrial genome. The studied sequences were homogeneous within-populations of both species, but there was a fixed difference in mtDNA between brown bears form the Alps and from the Apennines. Random drift since the time of isolation is a plausible explanation for both results. These findings suggest that wolves and bears have small effective population sizes and, thus, they will continue to loose genetic variability by random drift in the near future. Conservation efforts should be directed towards an increase of the annual growth rates of these populations. The individualization of discrete phylogeographic units in the brown bear suggests to manage them separately in order to preserve the existing gene diversity among populations.
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