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Towards a simplified taxonomy of Capsella bursa-pastoris (L.) Medik. (Brassicaceae)
Capsella bursa-pastoris (L.) Medik. is a species with a cosmopolitan distribution which shows considerable
morphological variation. Numerous authors have recognised widely differing numbers of varieties, microspecies
or other infraspecific subdivisions (segregates) of this species. In an attempt to clarify this situation,
we grew British material of the species under controlled conditions through to the F) generation to remove
environmental variation, and assessed the plants on the basis of a range of morphological criteria, namely leaf
shape, capsule size and also length of time taken to flower. Analysis of these characteristics consistently
produced four basic groups, which had been previously described. Herbarium specimens could also nearly
always be assigned to one of these groups. Limited chromosome counts suggest that two of these groups are
diploid and two are tetraploid. We suggest this fourfold division into broad groups reflects the major genetic
separations within the species, but that there is also considerable phenotypic plasticity shown by C. bursapastoris
in response to factors such as shade or trampling. These four groups appear to differ in their
geographic.al distribution in Britain.
KEYWORDS: Shepherd's Purse, morphological variation, leaf characters, capsule characters, chromosom
The Konya earthquakes of 10–11 September 2009 and soil conditions in Konya, Central Anatolia, Turkey
Earthquakes registering magnitudes <i>M</i><sub>d</sub> = 4.5 and 4.7 struck the city of Konya, Central Anatolia, on 10–11 September 2009, causing very slight damages. The earthquake epicenters were located at the east of Sille District along the Konya Fault Zone, a dip-slip fault. The nature and seismicity of the fault zone indicates that it is capable of producing earthquakes of moderate magnitudes. This paper summarizes the geologic data along the fault zone and documents groundwater conditions and analyzes borehole and geotechnical data of the Konya city. The residential area of the city covers an area of approximately 1150 square kilometers and consists almost entirely of flat land except for a small part of rugged land in the southwestern corner. Groundwater and geotechnical data were collected and analyzed to evaluate the liquefaction potential of deposits under the Konya city. This preliminary investigation indicates that areas for liquefaction are generally limited to the eastern and east central parts of the city
Interest rates and output in the long-run
In this paper we argue that both statistics and economic theory-based evidence largely indicate the absence of long run relationships between the real output and the most relevant monetary indicator for the U.K. and the U.S short term interest rates. These findings are not only a full sample result, but also valid in most of the subsamples throughout the second half of the 20th century
Force spectroscopy using bimodal frequency modulation atomic force microscopy
Cataloged from PDF version of article.We propose a force-spectroscopy technique where a higher order mode of a cantilever is excited simultaneously with the first. Resonance tracking of both vibration modes through a frequency modulation scheme provides a way to extract topographical information and the gradient of the tip-sample interaction within a single surface scan. We provide an analytic treatment of the scheme, derive expressions relating frequency shifts of the higher mode and the tip-sample forces, and offer two methods of improving the accuracy of reconstruction of the force gradient. Finally, we confirm our predictions by numerical simulations. © 2011 American Physical Society
Interest rates and output in the long-run
In this paper we argue that both statistics and economic theory-based evidence largely indicate the absence of long run relationships between the real output and the most relevant monetary indicator for the U.K. and the U.S, short term interest rates. These findings are not only a full sample result, but also valid in most of the sub-samples throughout the second half of the 20th century and are robust to the inclusion of possible omitted real variables
Cooling and heating by adiabatic magnetization in the NiMnIn magnetic shape memory alloy
We report on measurements of the adiabatic temperature change in the inverse
magnetocaloric NiMnIn alloy. It is shown that this alloy
heats up with the application of a magnetic field around the Curie point due to
the conventional magnetocaloric effect. In contrast, the inverse magnetocaloric
effect associated with the martensitic transition results in the unusual
decrease of temperature by adiabatic magnetization. We also provide
magnetization and specific heat data which enable to compare the measured
temperature changes to the values indirectly computed from thermodynamic
relationships. Good agreement is obtained for the conventional effect at the
second-order paramagnetic-ferromagnetic phase transition. However, at the first
order structural transition the measured values at high fields are lower than
the computed ones. Irreversible thermodynamics arguments are given to show that
such a discrepancy is due to the irreversibility of the first-order martensitic
transition.Comment: 5 pages, 4 figures. Accepted for publication in the Physical Review
Tsetse fly (Glossina pallidipes) midgut responses to Trypanosoma brucei challenge
Abstract Background Tsetse flies (Glossina spp.) are the prominent vector of African trypanosome parasites (Trypanosoma spp.) in sub-Saharan Africa, and Glossina pallidipes is the most widely distributed species in Kenya. This species displays strong resistance to infection by parasites, which are typically eliminated in the midgut shortly after acquisition from the mammalian host. Although extensive molecular information on immunity for the related species Glossina morsitans morsitans exists, similar information is scarce for G. pallidipes. Methods To determine temporal transcriptional responses of G. pallidipes to Trypanosoma brucei brucei challenge, we conducted Illumina based RNA-seq on midgut organ and carcass from teneral females G. pallidipes at 24 and 48 h post-challenge (hpc) with T. b. brucei relative to their respective controls that received normal blood meals (without the parasite). We used a suite of bioinformatics tools to determine differentially expressed and enriched transcripts between and among tissues, and to identify expanded transcripts in G. pallidipes relative to their orthologs G. m. morsitans. Results Midgut transcripts induced at 24 hpc encoded proteins were associated with lipid remodelling, proteolysis, collagen metabolism, apoptosis, and cell growth. Midgut transcripts induced at 48 hpc encoded proteins linked to embryonic growth and development, serine endopeptidases and proteosomal degradation of the target protein, mRNA translation and neuronal development. Temporal expression of immune responsive transcripts at 48 relative to 24 hpc was pronounced, indicative of a gradual induction of host immune responses the following challenge. We also searched for G. m. morsitans orthologous groups that may have experienced expansions in the G. pallidipes genome. We identified ten expanded groups in G. pallidipes with putative immunity-related functions, which may play a role in the higher refractoriness exhibited by this species. Conclusions There appears to be a lack of strong immune responses elicited by gut epithelia of teneral adults. This in combination with a compromised peritrophic matrix at this stage during the initial phase of T. b. brucei challenge may facilitate the increased parasite infection establishment noted in teneral flies relative to older adults. Although teneral flies are more susceptible than older adults, the majority of tenerals are still able to eliminate parasite infections. Hence, robust responses elicited at a later time point, such as 72 hpc, may clear parasite infections from the majority of flies. The expanded G. m. morsitans orthologous groups in G. pallidipes may also be functionally associated with the enhanced refractoriness to trypanosome infections reported in G. pallidipes relative to G. m. morsitans
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