Search results for "bee"
showing 10 items of 628 documents
A landscape-scale approach for linking farming strategies to weed communities and their contribution to ecosystem services
2019
National audience; Weeds present in agricultural fields provide habitats and trophic resources and as such contribute to the provision of ecosystem services such as pollination (quantity and quality of pollen and nectar in flowers) and biological control (seeds for pest natural enemies). The nature and amount of services provided depends on the floral composition of weed communities and this composition is driven by the combination of farming practices. Linking farming strategies to services is thus an important step to provide management guidelines for enhancing ecosystem services. We report here on such an analysis, based on agronomical and weed data collected annually in 70 field cores a…
Toward a better prediction of in-field weed regulation by carabid beetles in European arable landscapes
2019
International audience; Arable agriculture is still highly reliant on herbicides to manage weeds. As part of the necessary shift towards a reduction in pesticide use, the regulatory effect of seed-eating carabid beetles on weeds has received increasing attention in agroecological research. While strong evidence points to carabids exerting a regulatory effect on certain weed species, it is difficult to predict whether a particular assemblage of carabid species will drive the function of weed seed predation in field conditions. There are also uncertainties about which key local and landscape-scale factors affect the function of weed seed predation. In this paper, we report on specific researc…
Can Rhizoctonia solani disease be naturally controlled in a sugar beet field ?
2008
International audience
Beeta-alaniinin vaikutus 600 metrin juoksuaikaan
2016
Johdanto. Anaerobisessa maksimaalisessa suorituksessa (30 – 90 sekuntia) energia tuotetaan pääasiallisesti anaerobisen glykolyysin kautta, jonka haitallisina aineenvaihduntatuotteina syntyy laktaatti- ja vetyioneja. Näistä kahdesta vetyioni laskee veren pH-arvoa happamampaan suuntaan heikentäen lihassupistusta. Lihaksen ja veren happamuuden puskurointia voidaan parantaa muun muassa erilaisia lisäravinteita käyttämällä. Beeta-alaniinin on havaittu lisäävän solun sisäisen karnosiinin määrää. Karnosiini puskuroi solun sisällä happamuutta aiheuttavia vetyioneja lisäten anaerobista suorituskykyä. Tämän tutkimuksen tarkoituksena on selvittää onko lyhyellä beeta-alaniinin käyttöjaksolla vaikutusta…
The evolutionary dynamics of adaptive virginity, sex-allocation and altruistic helping in haplodiploid animals
2018
In haplodiploids, females can produce sons from unfertilized eggs without mating. However, virgin reproduction is usually considered to be a result of a failure to mate, rather than an adaptation. Here, we build an analytical model for evolution of virgin reproduction, sex-allocation, and altruistic female helping in haplodiploid taxa. We show that when mating is costly (e.g., when mating increases predation risk), virginity can evolve as an adaptive female reproductive strategy. Furthermore, adaptive virginity results in strongly divergent sex-ratios in mated and virgin queen nests ("split sex ratios"), which promotes the evolution of altruistic helping by daughters in mated queen nests. H…
A proctolin-like peptide is regulated after baculovirus infection and mediates in caterpillar locomotion and digestion
2022
Baculoviruses constitute a large group of invertebrate DNA viruses, predominantly infecting larvae of the insect order Lepidoptera. During a baculovirus infection, the virus spreads throughout the insect body producing a systemic infection in multiple larval tissues, included the central nervous system (CNS). As a main component of the CNS, neuropeptides are small protein-like molecules functioning as neurohormones, neurotransmitters, or neuromodulators. These peptides are involved in regulating animal physiology and behavior and could be altered after baculovirus infection. In this study, we have investigated the effect of Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) infection …
Nonlinear optical properties of diaromatic stilbene, butadiene and thiophene derivatives
2021
Series of highly polar stilbene (1a–e), diphenylbutadiene (2a–c) and phenylethenylthiophene (3a–c) derivatives were prepared via Horner–Wadsworth–Emmons method with a view to produce new and efficient materials for second harmonic generation (SHG) in the solid-state. The single-crystal X-ray structures of compounds 1–3 reveal extensive polymorphism and a peculiar photodimerization of the 2-chloro-3,4-dimethoxy-4′-nitrostilbene derivative 1a to afford two polymorphs of tetra-aryl cyclobutane 4. The stilbene congeners 2-chloro-3,4-dimethoxy-4′-nitrostilbene (1a·non-centro), 5-bromo-2-hydroxy-3-nitro-4′-nitrostilbene (1b) and 4-dimethylamino-4′-nitrostilbene (1e), as well as 4′-fluoro-4′′-nitr…
Performing arts and mediation technology in the period of lockdown
2021
Advancements in digital technologies have become novel ways to enrich communication, expression, and transmission of arts knowledge. Technology is increasingly implemented in the performance space, as a source of inspiration for artists. Especially in this period of lockdown, mediation technology has turned out to be an essential tool for different aspects of social life, as in performing arts. With venues, schools and artistic activities closed, performers, students and spectators have been obliged to keep connecting in remote conditions. This article wants to retrace the aesthetic impact of mediation technology in performing arts during this period of lockdown by focusing on the aspects t…
Vecchi e nuovi problemi in tema di intervento dei creditori nell’esecuzione (note a margine di Cass. S.U. n. 61 del 7 gennaio 2014)
2015
Nel contributo in oggetto l'autore, muovendo dalla decisione delle Sezioni Unite della Cassazione n. 61 del 7 gennaio 2014, coglie l'occasione per riesaminare le vecchie e nuove problematiche sottese all’intervento dei creditori nel processo esecutivo. Il primo tema affrontato è quello della par condicio creditorum, che viene esaminata nella sua storia evolutiva dal Code Napoleon, al suo periodo di massima estensione, dato dal codice del 1940, fino al suo ridimensionamento a seguito delle riforme del 2005. Esamina quindi la possibilità del possibile superamento quoad effectum della distinzione tra intervento di creditori con titolo e senza titolo, alla luce delle evoluzioni della giurisprud…
Estimating Tree Health Decline Caused by Ips typographus L. from UAS RGB Images Using a Deep One-Stage Object Detection Neural Network
2022
Various biotic and abiotic stresses are causing decline in forest health globally. Presently, one of the major biotic stress agents in Europe is the European spruce bark beetle (Ips typographus L.) which is increasingly causing widespread tree mortality in northern latitudes as a consequence of the warming climate. Remote sensing using unoccupied aerial systems (UAS) together with evolving machine learning techniques provide a powerful tool for fast-response monitoring of forest health. The aim of this study was to investigate the performance of a deep one-stage object detection neural network in the detection of damage by I. typographus in Norway spruce trees using UAS RGB images. A Scaled…