Search results for " environments"

Origin of the natural variation in the storage of dietary carotenoids in freshwater amphipod crustaceans

2020

16 pages; International audience; Carotenoids are diverse lipophilic natural pigments which are stored in variable amounts by animals. Given the multiple biological functions of carotenoids, such variation may have strong implications in evolutionary biology. Crustaceans such as Gammarus amphipods store large amounts of these pigments and inter-population variation occurs. While differences in parasite selective pressure have been proposed to explain this variation, the contribution of other factors such as genetic differences in the gammarid ability to assimilate and/or store pigments, and the environmental availability of carotenoids cannot be dismissed. This study investigates the relati…

Influence of Different Environments and Temperatures on the Photo-Oxidation Behaviour of the Polypropylene.

2022

The photo-oxidation of polypropylene at two different temperatures and in three different environments—air, distilled water and sea water—has been followed as a function of the irradiation time. The photo-oxidation kinetic is dramatically dependent on the amount of oxygen available for the oxidation reactions and on the temperature. While the photo-oxidation is very fast in air, the degradation is much slower in the two aqueous media. The degradation in sea water is slightly slower than in distilled water. In all cases, the degradation kinetic increases remarkably with the temperature. This behavior has been attributed to the lower oxygen availability for the oxidation reactions of the poly…

Sunny Island. An Interactive Learning Environment to Promote Systems Thinking Education for Primary School Students

2017

To make the process of learning easier for students, schoolteachers are increasingly using Interactive Learning Environments (ILEs) in classrooms. The paper presents a system dynamics-based ILE called Sunny Island. The ILE has been designed to promote Systems Thinking (ST) education for primary school students. Through a funny fantasy tale - described in detail in a book that accompanies the ILE - students have the opportunity to discover and become familiar with the basic principles of ST, such as feedback, positive and negative causal influences, limits to growth, short and long term effects, counterintuitive behaviors, causes of policy resistances and dynamic complexity. The proposed ILE…

Hidden entanglement, system-environment information flow and non-Markovianity

2014

It is known that entanglement dynamics of two noninteracting qubits, locally subjected to classical environments, may exhibit revivals. A simple explanation of this phenomenon may be provided by using the concept of hidden entanglement, which signals the presence of entanglement that may be recovered without the help of nonlocal operations. Here we discuss the link between hidden entanglement and the (non-Markovian) flow of classical information between the system and the environment.

Vertical transmission of naturally occurring Bunyamwera and insect-specific flavivirus infections in mosquitoes from islands and mainland shores of L…

2018

Background Many arboviruses transmitted by mosquitoes have been implicated as causative agents of both human and animal illnesses in East Africa. Although epidemics of arboviral emerging infectious diseases have risen in frequency in recent years, the extent to which mosquitoes maintain pathogens in circulation during inter-epidemic periods is still poorly understood. This study aimed to investigate whether arboviruses may be maintained by vertical transmission via immature life stages of different mosquito vector species. Methodology We collected immature mosquitoes (egg, larva, pupa) on the shores and islands of Lake Baringo and Lake Victoria in western Kenya and reared them to adults. Mo…

Geochemistry of Zr, Hf and REE in extreme water environments: hyperacid, hyper saline and lake waters in hydrothermal systems

This PhD thesis concerns the geochemistry of Zr, Hf and REE in extreme water environments characterized by a wide spectrum of chemical physical-parameters and compositions. The investigations were carried out in hypersaline waters covering a wide range of Eh values along Dead Sea Fault (Israel), in hyperacid waters circulating in Nevado del Ruiz volcano-hydrothermal system (Colombia) and in CO2-rich waters belonging to the Pantelleria volcano-hydrothermal system (Italy), including the alkaline lake “Specchio di Venere” formed within a calderic depression. The wide spectrum of chemical-physical conditions and various water chemical compositions interacting with different solid phases allowed…

The RAMON module: architecture framework and performance results

2003

A design study of a Re-configurable Access Module for Mobile Computing Applications is described. After a presentation of its cross-layered architecture, Control Parameters (CPs) of the module are introduced. The set of CPs both describes the functional state of the communication process in relation to the time-varying transport facilities and provides, as input of suitable Algorithms, the control information to re-configure the whole protocol stack for facing modified working conditions. The paper also presents the structure of the simulator realized to demonstrate the feasibility of the design guidelines and to evaluate reconfigurability performances.

Children’s conceptions of mental well-being and ideas for its promotion through digital environments

2021

The aim of this study is to further understanding of children’s conceptions of mental well-being and their ideas for its digital promotion. The study is based on the need to provide children an opportunity to actively participate and share their understanding of mental well-being promotion with others in light of their understanding of what online environments and their design can afford for this promotion. The study was implemented as three subsequent workshops in primary school classrooms comprising four teachers and 79 children aged 9-11 years old. In the first two workshops, children reflected on mental well-being, digital environments they utilise and their possible connections to ment…

CHEMICAL AND BOTANICAL CHARACTERIZATION OF A ROSMARINUS OFFICINALIS L. BIOTYPE FROM SICILY

2006

Rosemary (Rosmarinus officinalis L.) is widely cultivated all over the world as ornamental and aromatic plant. Today, the interest towards its cultivation is strongly arising, due to the many biological activities exerted by the essential oil extracted from its leaves and flowers. Which compounds confer to Rosemary's essential oil its properties is still unclear, but it seems likely that these effects must be attributed to a mixture of different principles, acting contemporarily and synergically. The diverse composition of the essential oils of Rosemary's ecotypes coming from different geographical areas could be the reason of their various level of activity. With the aim of obtaining furth…

Rapid evolutionary adaptation to elevated salt concentrations in pathogenic freshwater bacteria Serratia marcescens.

2014

Rapid evolutionary adaptions to new and previously detrimental environmental conditions can increase the risk of invasion by novel pathogens. We tested this hypothesis with a 133-day-long evolutionary experiment studying the evolution of the pathogenic Serratia marcescens bacterium at salinity niche boundary and in fluctuating conditions. We found that S. marcescens evolved at harsh (80 g/L) and extreme (100 g/L) salt conditions had clearly improved salt tolerance than those evolved in the other three treatments (ancestral conditions, nonsaline conditions, and fluctuating salt conditions). Evolutionary theories suggest that fastest evolutionary changes could be observed in intermediate sele…