Search results for "MPT"
showing 10 items of 15064 documents
Dynamics of PHA-induced immune response and plasma carotenoids in birds: should we have a closer look?
2009
SUMMARY Allocation trade-offs of limited resources are thought to ensure the honesty of sexual signals and are often studied using controlled immune challenges. One such trade-off between immunity and ornaments is that involving carotenoids. Phytohemagglutinin (PHA)-induced immune response is a widely used immune challenge, yet more details on the underlying physiological mechanisms and potential costs are needed. We investigated the temporal dynamics of PHA-induced immune response and associated changes in blood carotenoids, body mass and a carotenoid-based coloured signal. We found variation in individual response patterns to PHA after peak swelling was reached, with birds showing either …
Egalitarian mixed-species bird groups enhance winter survival of subordinate group members but only in high-quality forests
2020
AbstractOnly dominant individuals have unrestricted access to contested resources in group-living animals. In birds, subordinates with restricted access to resources may respond to intragroup contests by acquiring extra body reserves to avoid periods of food shortage. In turn, higher body mass reduces agility and increases predation and mortality risk to subordinates. Birds often live in hierarchically organized mixed-species groups, in which heterospecific individuals are considered to substitute for conspecifics as protection against predators at a significantly reduced competition cost. Crested tits (Lophophanes cristatus) and willow tits (Poecile montanus) form mixed-species groups duri…
Testosterone-Mediated Effects on Fitness-Related Phenotypic Traits and Fitness
2009
International audience; The physiological and behavioral mechanisms underlying life-history trade-offs are a continued source of debate. Testosterone (T) is one physiological factor proposed to mediate the trade-off between reproduction and survival. We use phenotypic engineering and multiple laboratory and field fitness-related phenotypic traits to test the effects of elevated T between two bank vole Myodes glareolus groups: dominant and subordinate males. Males with naturally high T levels showed higher social status (laboratory dominance) and mobility (distance between capture sites) than low-T males, and the effect of T on immune response was also T group specific, suggesting that behav…
Mechanical properties of natural fiber composites produced using dynamic sheet former
2018
Composites formed from wood fibers and man-made cellulosic fibers in PLA (polylactic acid) matrix, manufactured using sheet forming technique and hot pressing, are studied. The composites have very low density (due to high porosity) and rather good elastic modulus and tensile strength. As expected, these properties for the four types of wood fiber composites studied here improve with increasing weight fraction of fibers, even if porosity is also increasing. On the contrary, for man-made cellulosic fiber composites with circular fiber cross-section, the increasing fiber weight fraction (accompanied by increasing void content) has detrimental effect on stiffness and strength. The differences …
Circummed pine forest database: An electronic archive for mediterranean and submediterranean pine forest vegetation data
2019
Large thematic databases of vegetation plots are increasingly needed for vegetation studies and biodiversity research. In this paper, we present the CircumMed Pine Forest Database (GIVD ID: EU-00-026), which in November 2018, comprised records from 6317 pine-dominated vegetation plots (relevés) and associated vegetation types from 20 countries of the Mediterranean Basin, Near East and Crimea. These vegetation plots were collected through a detailed literature search for plots not previously included in the European Vegetation Archive (EVA), in order to fill geographic gaps in data coverage. The database comprises Mediterranean (including Oromediterranean) pine-forest vegetation plots from b…
Conflicts between touristic recreational activities and breeding shearwaters: short-term effect of artificial light and sound on chick weight
2018
Human disturbances are increasingly becoming a conservation concern for many populations of colonial seabirds. Colonially reproducing species are particularly vulnerable to localised disturbances because detrimental elements can simultaneously affect the entire population. Studies of petrels and shearwaters have shown that light pollution, in particular, can be harmful for both fledglings and adults, but little is known of the way such anthropogenic elements affect the quality of parental care at the nest. Chick provisioning in petrels and shearwaters occurs exclusively at night and is also negatively correlated with the amount of moonlight. We tested the hypothesis that high-intensity ligh…
Transformation of agricultural landscapes in the Anthropocene: Nature's contributions to people, agriculture and food security
2020
Fil: Vanbergen, Adam J. Université de Bourgogne Franche-Comté. AgroSup Dijon. Agroécologie. Francia. Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Rio Negro, Argentina. Fil: Aizen, Marcelo A. Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina. Instituto de Investigaciones en Biodiversidad y Medioambiente. Rio Negro, Argentina. Fil: Cordeau, Stephane. Université de Bourgogne Franche-Comté. AgroSup Dijon. Agroécologie. Francia. Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Ga…
Behaviour of consumers of conventional and organic flowers and ornamental plants in Italy
2013
The paper analyses preferences and motivations of Italian consumers of flowers and ornamental plants, both conventional and organic. The results helped to outline their profile. Purchases are still done in the traditional places (flower shops for cut flowers and plant nurseries for potted plants), however positive trend is found for potted plants purchases at large distribution chains. Some differences came out as to purchase motivations: cut flowers are mainly bought in special occasions whereas potted plants purchases are linked to personal use. The results confirm a positive relationship between the purchase of flowers and plants and the age of the interviewees, besides showing that wome…
Effect of Harvest Date on Mango (Mangifera Indica L. Cultivar Osteen) Fruit’s Qualitative Development, Shelf Life and Consumer Acceptance
2021
The qualitative characteristics of mango fruits change throughout their development process and are also influenced by their duration. Harvesting at different times after the fruit set affects external and internal quality and the post-harvest behavior and management possibilities of the fruits. The objective of this study was to assess the evolution of the most important physicochemical and organoleptic parameters of cv. Osteen fruits concern the length of their stay on the plant and also to their post-harvest management. For this reason, fruits were harvested progressively in ten pickings. The study showed that mango fruits that are kept on the tree reach the best quality traits, correspo…
Vegetation of Middle Asia – the project state of art after ten years of survey and future perspectives
2017
Middle Asia is one of the most diverse regions on earth with high endemism of vascular plants and remarkable habitat richness, mainly due to the considerable altitudinal range (300-7,500 m a.s.l.). The region is considered as one of the 34 global biodiversity hotspots. This paper presents the Vegetation of Middle Asia database (VMA; GIVD ID: AS-00-003; http://www.givd.info/ID/AS-00-003) which is the regional database that covers the area of Tajikistan, Kyrgyzstan and Uzbekistan. The database contains phytosociological relevés collected between the years 2006 and 2016 in different vegetation types with the use of the Braun-Blanquet method. The covered vegetation types include: deciduous fore…