Search results for "cycle"
showing 10 items of 3119 documents
Ecological and economic indicators for the evaluation of almond (Prunus dulcis l.) orchard renewal in sicily
2020
Globally, almond production is experiencing a growing trend thanks to a strong interest in the health, gastronomic, and industrial properties that are linked to the fruits and their derivatives. After a constant and marked decline in the second half of the last century, the Mediterranean Basin is thoroughly reassessing this crop, which provides significant results with a modern orchard management. The opportunity determined by the transition from traditional to modern systems have increased the interest in evaluating the different environmental impacts of the two cultivation models that still coexist today. In this work, through the application of the Life Cycle Assessment (LCA) and an econ…
Le due crisi: crisi del capitalismo e crisi ambientale. Una soluzione sostenibile? (parte II)
2016
Vista nella Parte I la gravità della crisi ambientale, soprattutto l’instabilità climatica che caratterizzerà le prossime decadi, nella parte II si esplicitano le ragioni profonde della necessità di cambiare, e come, il modello di sviluppo. Negli ultimi quarant’anni la crisi ecologica non è mai diventata una variabile importante nelle politiche economiche. Colpa del neo-liberismo imperante, dall’ “unilateralismo” dell’amministrazione USA al “fiscal compact” della UE? Sì, ma anche le altre scuole economiche commettono lo stesso errore. L’attuale crisi del capitalismo è una crisi di sovrapproduzione, il cui carattere quantitativo, dovuto all’innovazione tecnologica nel mercato globalizzato, r…
An existence and uniqueness principle for a nonlinear version of the Lebowitz-Rubinow model with infinite maximum cycle length
2017
The present article deals with existence and uniqueness results for a nonlinear evolution initial-boundary value problem, which originates in an age-structured cell population model introduced by Lebowitz and Rubinow (1974) describing the growth of a cell population. Cells of this population are distinguished by age a and cycle length l. In our framework, daughter and mother cells are related by a general reproduction rule that covers all known biological ones. In this paper, the cycle length l is allowed to be infinite. This hypothesis introduces some mathematical difficulties. We consider both local and nonlocal boundary conditions.
Galerucella nymphaeae (Col., Chrysomelidae) grazing increases Nuphar leaf production and affects carbon and nitrogen dynamics in ponds.
1990
The grazing effects of the waterlily beetle Galerucella nymphaeae on Nuphar lutea stands were studied in three ponds in Central Finland. Production of floating leaves of N. lutea and growth in the G. nymphaeae population were investigated in the ponds and bioenergetics of the beetle larvae in the laboratory. Combination of field and laboratory data enabled estimation of the effect of the beetle on the production of floating leaves of N. lutea and the consequences of grazing for the input of detritus from Nuphar into the ponds. Adults and larvae of G. nymphaeae consumed 3.0–6.1% of the net annual floating leaf production during the growing period. In addition to consumption losses, feeding a…
Optimizing the Integration Area and Performance of VLIW Architectures by Hardware/Software Co-design
2021
The cost and the performance are major concerns that the designers of embedded processors shall take into account, especially for market considerations. In order to reduce the cost, embedded systems rely on simple hardware architectures like VLIW (Very Long Instruction Word) processors and they look for compiler support. This paper aims at developing a design space explorer of VLIW architectures from different perspectives like processing performance and integration area. A multi-objective Genetic Algorithm (GA) was used to find the optimum hardware configuration of an embedded system and the optimization rules applied by compiler on the benchmarks code. The first step consisted in represen…
Food resources and intestinal parasites as limiting factors for boreal vole populations during winter
2014
Processes limiting the growth of cyclic vole populations have stimulated considerable research and debate over several decades. In Fennoscandia, the peak density of cyclic vole populations occurs in fall, and is followed by a severe winter decline. Food availability and intestinal parasites have been demonstrated to independently and synergistically limit wildlife populations. The purpose of this study was to directly compare competing food and parasite hypotheses on the limitation of overwintering high-density vole populations. Moreover, we evaluated the ability of food limitation and nematode infection to interact and thereby intensify population declines. A two-factor experiment with foo…
Fluctuating asymmetry and immune function in a field cricket
2004
Recently, fluctuating asymmetry (FA) of morphological traits has attracted great attention as a short-cut measure of individual quality. Whereas there is some evidence that FA of sexual ornaments is negatively associated with immune function, studies concerning FA and immune function in non-ornamental traits are absent. Here, we tested whether FA of three non-ornamental traits in hind limbs is related to male immune function in a population of the Mediterranean field cricket, Gryllus bimaculatus. As different measures of male immune function, we used encapsulation rate and lytic activity. We found that a composite measure of FA (cFA) was negatively related to encapsulation rate. However, ly…
Population dynamics of oxiclinal species in lake Arcas-2 (Spain)
1995
‘Oxiclinal’ rotifer species show high concentrations just above the oxic-anoxic interface in the hypolimnion of some lakes. The stratification of their populations is best shown by sampling at close depth intervals and quantifying their densities by the Utermohl technique. With this technique we were able to count males which otherwise pass through filters and more accurately count egg production. We evaluated female, male and egg numbers of the two main oxiclinal species of lake Arcas-2: Filinia hofmanni and Anuraeopsis fissa, during two annual cycles (1990–91). F. hofmanni was an exclusive oxiclinal species. It had an exponential growth phase at the onset of stratification giving a distin…
The Female Handball Player
2018
Female hormones fluctuate in concentrations during the menstrual cycle. This has triggered speculations among athletes, coaches, as well as researchers about the hormonal changes that lead to variations in athletic performance and adaptation to training. Many athletes, as in the general population, use oral contraceptives. This has raised questions concerning the suppression of the endogenous circulating female hormones and if the administration of synthetic hormones may have negative impact on athletic performance and training adaptations – or the opposite.
Computational Thinking Development: Benefiting from Educational Robotics in STEM Teaching
2022
<p style="text-align: justify;">The delivery of science, technology, engineering and mathematics (STEM) learning to improve an individual’s competence and future career interests has become a critical scientific undertaking for teachers and researchers alike. A plethora of research has proposed various hands-on robotics activities built on constructivist theories, thereby facilitating the development of knowledge based on reality for scientific and non-scientific stakeholders. Robotics may become an essential focus point within technology provision, which is an essential underlying characteristic for the seminal development of computational thinking (CT). However, despite the potentia…