Search results for "ATTRACTION"
showing 10 items of 152 documents
Modal attraction on low order modes by Kerr effect in a graded refractive index multimode fiber
2018
Modal attraction towards low order modes in a GRIN multimode fiber was experimentally observed at high power and characterized, thus enriching the dynamics of the Kerr self-cleaning effect leading to quasi fundamental mode generation.
Interspecific attraction between ground-nesting songbirds and ants: the role of nest-site selection
2021
Abstract Background Interspecific interactions within ecological networks can influence animal fitness and behaviour, including nest-site selection of birds and ants. Previous studies revealed that nesting birds and ants may benefit from cohabitation, with interspecific attraction through their nest-site choice, but mutual interactions have not yet been tested. We explored a previously undescribed ecological link between ground-nesting birds and ants raising their own broods (larvae and pupae) within the birds’ nests in a temperate primeval forest of lowland Europe. We tested whether the occurrence of ant broods within bird nests resulted from a mutual or one-sided interspecific attraction …
QR kodu kā tirdzniecības instrumenta atbilstība uzņēmumiem
2021
Tā kā tehnoloģija ir pārņēmusi mārketinga pasauli, visefektīvākais mārketinga veids ir mobilais mārketings, un, mainoties tendencēm, daudzi mārketinga rīki ir praktizējuši, lai sniegtu produktīvu reklāmu. QR kodi pēdējos gados ir kļuvuši par jauno mārketinga tendenci, taču problēma ir tā, vai šie QR kodi patiešām ir produktīvi viņu centienos. Šī pētījuma mērķis ir analizēt, vai uzņēmumi, kas izmanto QR kodus kā savu mārketinga rīku, var sasniegt savus mērķus vai neietekmē mārketinga shēmas, kā arī noskaidrot, vai cilvēki zina QR kodus un vai tie tos ietekmē / piesaista. Pētījuma rezultāti acīmredzami atrisina pētījuma problēmu, uzņēmumi, kas izmanto QR kodus kā mārketinga rīku, sasniedz sav…
PUBLIC SPACES: resources for the city or places of conflict?
2019
Public spaces, whether they be indoors or out, are an important part of cities. They are the places of everyday life that have, over time, undergone a phase of decline. Today, in fact, they are under used, unattractive, unsafe and reflect the state of health of urban centers and their inhabitants. This study investigates the quality of public spaces of some urban realities - national and international - which have become examples of sustainable urban regeneration, places of sociality and hospitality.
The Ghost of the Hawk: Top Predator Shaping Bird Communities in Space and Time
2021
Despite the wide recognition that strongly interacting species can influence distributions of other species, species interactions are often disregarded when assessing or projecting biodiversity distributions. In particular, it remains largely uncharted the extent to which the disappearance of a keystone species cast repercussions in the species composition of future communities. We tested whether an avian top predator can exert both positive and negative effects on spatial distribution of other species, and if these effects persist even after the predator disappeared. We acquired bird count data at different distances from occupied and non-occupied nests of Northern goshawks Accipiter genti…
Antibiotics and Resistance: A Fatal Attraction
2013
When penicillin and other classes of antibiotics were discovered and used to treat infectious diseases human morbidity and mortality due to infective microorganisms were successfully contrasted. However, almost as soon as antibacterial drugs were introduced in clinics, bacterial resistance spread. From a biological and microbiological viewpoint, antibacterial drug resistance is a fascinating aspect of molecular evolution, and resistome concept has been introduced to shed light on driving forces that control the spreading and maintenance of resistance genes within microbial populations. Despite the wide range of chemical complexity of antibiotics, there is a restricted number of modes of act…
Les espaces imprécis
1993
La plupart des concepts employés en analyse spatiale sont définis et formalisés de manière à rendre compte des phénomènes spatiaux réels maisconsidérés comme précis. Si l'imprécision, a u même titre que 1 incertitude est une forme d'inexactitude, il importe de les distinguer. En particulier, l'incertitude concerne des événements futurs ou imprévisibles et sa prise en compte requiert l'usage de la théorie des probabilités. L'imprécision caractérise aussi bien les phénomènes présents et futurs (qui sont alors également incertains) et nécessite l'usage d'une axiomatique différente. Celle-ci, construite sur un semi-corps de Borel, fait appel au concept de valuation au lieu du concept de mesure.…
Attraction d'ondes pour des systèmes à résonance d'ondes contra-propagatives
2011
Wave attraction in counter-propagating waves systems is a general phenomenon that was first established in Physics in the context of the attraction of the polarization between two counter-propagating waves in optical fibers. This phenomenon has been observed experimentally, and its properties were studied through numerical simulations. The models are Hamiltonian hyperbolic systems of partial differential equations, with time-dependent boundary conditions on a finite interval. The underlying mechanism can be traced back to the existence of singular tori in the corresponding stationary equations. In this work we analyze in detail the simplest example in this family of models. We show that mos…
Nectar-Inhabiting Bacteria Affect Olfactory Responses of an Insect Parasitoid by Altering Nectar Odors
2022
AbstractFloral nectar is ubiquitously colonized by a variety of microorganisms among which yeasts and bacteria are the most common. Microorganisms inhabiting floral nectar can alter several nectar traits, including nectar odor by producing microbial volatile organic compounds (mVOCs). Evidence showing that mVOCs can affect the foraging behavior of insect pollinators is increasing in the literature, whereas the role of mVOCs in altering the foraging behavior of third-trophic level organisms such as insect parasitoids is largely overlooked. Parasitoids are frequent visitors of flowers and are well known to feed on nectar. In this study, we isolated bacteria inhabiting floral nectar of buckwhe…
Dimethyl disulfide and dimethyl trisulfide: so similar yet so different in evoking biological responses in saprophilous flies
2014
Dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS) are used by saprophilous insects to locate breeding sites (decaying organic matter), and by brood-site deceptive flowers to attract such insects. However, little is known about the relative importance of these two compounds in eliciting electrophysiological and behavioral responses in the insects. Here, we compared the relative attractiveness of DMDS and DMTS to saprophilous flies in field choice experiments and tested whether potential differences in field responses can be explained by differences in electrophysiological antennal responses to these compounds. Field experiments revealed that the attractiveness of a mixture of these co…