Search results for "evolution"

The energetic cost of humoral immunity in the Collared Dove, Streptopelia decaocto : is the magnitude sufficient to force energy-based trade-offs?

2005

International audience; 1. Energy saving is often suggested as the basis of a resource trade-off between immunocompetence and other fitness-relevant traits. This suggests that the energetic cost of an immune response is significant and sufficient to force trade-offs. To date, few studies have investigated the energetic cost of the humoral component of the immune system in birds and furthermore, existing results are contradictory. 2. We addressed this question through two experiments. In experiment 1, the basal metabolic rate (BMR) of Collared Doves, Streptopelia decaocto , challenged with sheep red blood cells (SRBC) was compared with the BMR of control birds. The energetic cost of immunity…

Transcription factors controlling development and function of innate lymphoid cells.

2014

Abstract Innate lymphoid cells (ILCs) are a heterogeneous group of lymphocytes, which play an important role in tissue homeostasis at epithelial surfaces. They are scarce in spleen and lymph nodes, but substantial numbers can be found in the intestinal mucosa even at steady state. There, they represent the first line of defence against invading pathogens and contribute to lymphorganogenesis, tissue repair and, when inappropriately activated, immune pathology. Lineage-specific development, function and maintenance of these cells depend on a restricted set of transcription factors that partially emerged as a result of diversification and selection during vertebrate evolution. The differential…

Hemocyanin in mollusks--a molecular survey and new data on hemocyanin genes in Solenogastres and Caudofoveata.

2008

The most common respiratory protein of mollusks is the blue, copper-containing hemocyanin (van Holde and Miller, 1995). It is not bound to hemocytes but suspended in the hemolymph. Its molecular mass ranges from 3500 10 to 8000 10 Da (dalton) or even more (Herskovits, 1988). These differences in molecular weight are due to the fact that the basic decamers that constitute the barrel-shaped protein may aggregate to didecamers or multidecameric elongated particles (Herskovits, 1988). In cephalopods and chitons (Polyplacophora), there are exclusively decamers, whereas in protobranch bivalves and gastropods the predominantly observed aggregation state is didecamers (Herskovits, 1988; van Holde a…

Effects of 24 h Compression Interventions with Different Garments on Recovery Markers during Running

2021

Compression and temperature manipulation are discussed as strategies to improve performance markers and recovery in sports. Here, we investigate the effects of compression stockings made with fabric, either combined or not with heating and cooling substances, on variables related to running performance and recovery. Ten trained runners (mean ± standard deviation age 45 ± 9 years old, body mass 69 ± 7 kg, height 166 ± 4 cm) with no experience of using compression garments performed an intense running session of 10 km, then wore a stocking for 24 h (randomized

Sex-specific effects of natural and sexual selection on the evolution of life span and ageing in Drosophila simulans

2014

Summary Variation in the strength of age-dependent natural selection shapes differences in ageing rates across species and populations. Likewise, sexual selection can promote divergent patterns of senescence across the sexes. However, the effects of these processes on the evolution of ageing have largely been considered independently, and interactions between them are poorly understood. We use experimental evolution to investigate how natural and sexual selection affect life span and ageing in Drosophila simulans. Replicate populations were evolved under lifetime monogamy (relaxed sexual selection) or lifetime polyandry (elevated sexual selection) and at one of two temperatures, 25 °C (rela…

Leaps and bounds : towards an integrative theory of cultural evolution

2014

Tutkimuksessa pyritään yhdistämään ajatus kulttuurista eräänlaisen luonnonvalinnan alaisena Dan Sperberin näkemyksien (1) kommunikaation taustadynamiikasta tarkoitet-tujen merkityksien päättelynä niiden kontekstisidonnaisen merkittävyyden perusteella ja (2) erilaisten käsityksien eri kohteista leviämisen suhteen. Tällaisen yhdentävän viiteke-hyksen turvin pyritään vastaamaan pätevästi Sperberin kritiikkiin koskien darwinilaisen luonnonvalinnan soveltamista kulttuurin ilmiöihin. Näihin kritiikkeihin lukeutuvat väitteet, että (1) kulttuurin muutostiheys on liian korkea evoluution tuloksien kasautumisen mahdol-listamiseksi, (2) yleistykset koskien sisältöjä ovat kestämättömiä tehtyjen yliyksin…

Sequence of deformation in the sicilidi units (northern sicilian chain)

2004

The foredeep deposits of Northern Sicily, indicated as Sicilidi units, have undergone different deformations' since Oligocene time. The resulting tectonic Structures, analysed in several outcrops in the Eastern Madonie Mts, are 1 cm-to- 100 m in scale and are similar to the larger structures forming the Sicily belt, allowing for scale extrapolation. Also the overprinting relationships of the minor structures recorded in the so-called Tufiti di Tusa reflect the sequence of fault activation which determined the present-day geometry of the tectonic units, suggesting that the tectonic evolution of the foreland basin developed during the stacking of the Maghrebide fold-and-thrust belt. The overp…

Parallel global optimization : structuring populations in differential evolution

2010

Land Snail Communities in Limestone Gorges from the Southern Part of the Metaliferi Mountains (Apuseni Mountains, Romania)

2018

Abstract This study focuses on terrestrial gastropod communities in a karst area, where the presence of water and the limestone generates favourable environment for land snails. Three limestone gorges were analysed located in the southeast of the Metaliferi Mountains. Four different habitats in three limestone gorges were analysed – Glodului, Cibului and Mada. A total of 42 species of land snails were identified. The terrestrial gastropod communities in the area are dominated by calciphile species, such as Granaria frumentum, Truncatellina cylindrica and Alopia bielzii madensis. The differences between the analysed habitats are not pronounced enough to be reflected in the structure of the s…

Scanning Tunneling Spectroscope Use in Electrocatalysis Testing

2010

Published version of an article from the journal: Materials (1996-1944). Also available from publisher: http://dx.doi.org/10.3390/ma3063675 The relationship between the electrocatalytic properties of an electrode and its ability to transfer electrons between the electrode and a metallic tip in a scanning tunneling microscope (STM) is investigated. The alkaline oxygen evolution reaction (OER) was used as a test reaction with four different metallic glasses, Ni78Si8B14, Ni70Mo20Si5B5, Ni58Co20Si10B12, and Ni25Co50Si15B10, as electrodes. The electrocatalytic properties of the electrodes were determined. The electrode surfaces were then investigated with an STM. A clear relationship between the…