Особенности ценообразования на рынке экскурсионных услуг Крыма

Цель статьи – анализ специфики ценообразования на экскурсионные услуги в Крыму как важного фактора развития этого рынка

Malaria transmission in Dakar: A two-year survey

<p>Abstract</p> <p>Background</p> <p>According to entomological studies conducted over the past 30 years, there was low malaria transmission in suburb of Dakar but little evidence of it in the downtown area. However; there was some evidence of local transmission based on reports of malaria among permanent residents. An entomological evaluation of malaria transmission was conducted from May 2005 to October 2006 in two areas of Dakar.</p> <p>Methods</p> <p>Mosquitoes were sampled by human landing collection during 34 nights in seven places in Bel-air area (238 person-nights) and during 24 nights in five places in Ouakam area (120 person-nights). Mosquitoes were identified morphologically and by molecular methods. The <it>Plasmodium falciparum </it>circumsporozoïte indexes were measured by ELISA, and the entomological inoculation rates (EIR) were calculated for both areas. Molecular assessments of pyrethroid knock down resistance (<it>Kdr</it>) and of insensitive acetylcholinesterase resistance were conducted.</p> <p>Results</p> <p>From May 2005 to October 2006, 4,117 and 797 <it>Anopheles gambiae s.l</it>. respectively were caught in Bel-air and Ouakam. Three members of the complex were present: <it>Anopheles arabiensis </it>(> 98%), <it>Anopheles melas </it>(< 1%) and <it>An. gambiae s.s</it>. molecular form M (< 1%). Infected mosquitoes were caught only during the wintering period between September and November in both places. In 2005 and 2006, annual EIRs were 9,5 and 4, respectively, in Bel-air and 3 and 3, respectively, in Ouakam. The proportion of host-seeking <it>An. gambiae s.l</it>. captured indoors were 17% and 51% in Bel air and Ouakam, respectively. Ace 1 mutations were not identified in both members of the <it>An. gambiae </it>complex. <it>Kdr </it>mutation frequency in <it>An. arabiensis </it>was 12% in Bel-air and 9% in Ouakam.</p> <p>Conclusion</p> <p>Malaria is transmitted in Dakar downtown area. Infected mosquitoes were caught in two subsequent years during the wintering period in two distant quarters of Dakar. These data agree with clinical data from a Senegalese military Hospital of Dakar (Hospital Principal) where most malaria cases occurred between October and December. It was the first detection of <it>An. melas </it>in Dakar.</p

Future perspectives in melanoma research. Meeting report from the "Melanoma Research: a bridge Naples-USA. Naples, December 6th-7 th2010"

Progress in understanding the molecular basis of melanoma has made possible the identification of molecular targets with important implications in clinical practice. In fact, new therapeutic approaches are emerging from basic science and it will be important to implement their rapid translation into clinical practice by active clinical investigation

Three essays in optimal consumption

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Economics, 1989.Includes bibliographical references.by Henri Frederic Pagès.Ph.D

Evaluating a key herbivorous fish as a mobile link: a Brownian bridge approach

12 páginas, 1 tabla, 3 figuras, 1 suppl.By moving between habitats, mobile link organisms serve as vectors of material and energy transport between ecosystems. Additionally, if these mobile species are key organisms, their movement patterns can have profound consequences on the functioning of the ecosystems they link. The Mediterranean herbivorous fish Sarpa salpa has been defined as a key organism in seagrass and rocky macroalgal habitats. Our objective in this study was to evaluate the potential of this species to be considered a mobile link by: (1) assessing its capacity to connect different habitats, the strength of these connections, and the habitat use; and (2) determining whether the patterns observed were consistent on a diel basis and over an annual period. We used the recently developed Brownian bridge movement models (BBMM) framework to analyse the movement patterns of 18 fish tracked with passive acoustic telemetry (mean tracking duration: 103 ± 22 d) and a time-frequency analysis to assess their temporal patterns. Our results showed that S. salpa performed trips between different and distant habitats (on the order of km) with large home ranges (overall mean: 134 ± 10 ha). Despite its high mobility, S. salpa used seagrass more intensively rather than rocky habitats. In addition, our results confirm the existence of diel patterns for this species, mostly observed in the seagrass habitat, with fish moving from shallow areas during the day to deeper areas at night. These patterns were visible for most of the year. Taken together, these results suggest that S. salpa may act as a mobile link by connecting shallow and deep areas of the meadow on a daily basis and linking different and distant habitats over longer temporal scales.This research has been funded by the Spanish Ministry of Science and Innovation (projects CTM2010- 22273-C02-01 and -02). The Spanish Ministry of Education supported J.F.P. (scholarship AP2008-01601).Peer reviewe

Modelling the interactions between root system architecture, root functions and reactive transport processes in soil

Soil-plant models always oversimplified the representation of soil chemical processes or root system. The objectives of the study were (i) to present a model overcoming such limitations, and (ii) to illustrate its relevance for the modelling of soil-plant interactions. We coupled a root system architecture (RSA) model with a reactive transport model using a macroscopic approach. The two models were coupled sequentially using Fortran-C++ interoperability. We used the resulting model to investigate the case of phosphorus (P) acquisition from hydroxyapatite (HA) in an alkaline soil as induced by P and calcium (Ca) uptake and pH variations in the root zone. Important model parameters were issued of the literature and we tested its sensitivity to selected soil properties. Model sensitivity to grid size and time increment was evaluated as well. The simulations revealed that HA dissolution can contribute very substantially to P nutrition in case of rhizosphere alkalisation thanks to Ca and P uptake. Root-induced acidification was much more efficient at acquiring P, suggesting that ammonium-fed plants should be more P efficient. The variations of dissolved P in the root zone partly agreed with the observations, suggesting that P release was rather controlled by desorption when alkalisation occurs. The presence of more soluble minerals as well as the increase of Ca uptake should enhance P acquisition by crops. We developed a new model and demonstrated the interest of the mechanistic description of geochemical processes with a spatially-explicit distribution of roots in soil while modelling soil-plant interactions. Results of its first application to P acquisition from a mineral source in an alkaline soil were overall consistent with the literature

The scent of fear makes sea urchins go ballistic

Este artículo contiene 12 páginas, 4 figuras, 1 tabla.Background: Classic ecological formulations of predator–prey interactions often assume that predators and prey interact randomly in an information-limited environment. In the feld, however, most prey can accurately assess predation risk by sensing predator chemical cues, which typically trigger some form of escape response to reduce the probability of capture. Here, we explore under laboratory-controlled conditions the long-term (minutes to hours) escaping response of the sea urchin Paracentrotus lividus, a key species in Mediterranean subtidal macrophyte communities. Methods: Behavioural experiments involved exposing a random sample of P. lividus to either one of two treatments: (i) control water (fltered seawater) or (ii) predator-conditioned water (with cues from the main P. lividus benthic predator—the gastropod Hexaplex trunculus). We analysed individual sea urchin trajectories, computed their heading angles, speed, path straightness, difusive properties, and directional entropy (as a measure of path unpredictability). To account for the full picture of escaping strategies, we followed not only the frst instants post-predator exposure, but also the entire escape trajectory. We then used linear models to compare the observed results from control and predators treatments. Results: The trajectories from sea urchins subjected to predator cues were, on average, straighter and faster than those coming from controls, which translated into diferences in the difusive properties and unpredictability of their movement patterns. Sea urchins in control trials showed complex difusive properties in an information-limited environment, with highly variable trajectories, ranging from Brownian motion to superdifusion, and even marginal ballistic motion. In predator cue treatments, variability reduced, and trajectories became more homogeneous and predictable at the edge of ballistic motion. Conclusions: Despite their old evolutionary origin, lack of cephalization, and homogenous external appearance, the trajectories that sea urchins displayed in information-limited environments were complex and ranged widely between individuals. Such variable behavioural repertoire appeared to be intrinsic to the species and emerged when the animals were left unconstrained. Our results highlight that fear from predators can be an important driver of sea urchin movement patterns. All in all, the observation of anomalous difusion, highly variable trajectories and the behavioural shift induced by predator cues, further highlight that the functional forms currently used in classical predator–prey models are far from realistic.The Spanish Ministry of Science and Innovation funded this research (project CTM2010-22273-C02, CTM2017-86695-C3-1-R, CTM2017-86695-C3-3-R, and CGL78156-C2-R1). JFP acknowledges fnancial support from the Spanish Ministry of Education (scholarship AP2008-01601) and the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 795315.Peer reviewe

Simulating the effects of water limitation on plant biomass using a 3D functional–structural plant model of shoot and root driven by soil hydraulics

International audience• Background and Aims Improved modelling of carbon assimilation and plant growth to low soil moisture requires evaluation of underlying mechanisms in the soil, roots, and shoots. The feedback between plants and their local environment throughout the whole spectrum soil-root-shoot-environment is crucial to accurately describe and evaluate the impact of environmental changes on plant development. This study presents a 3D functional structural plant model, in which shoot and root growth are driven by radiative transfer, photosynthesis, and soil hydrodynamics through different parameterisation schemes relating soil water deficit and carbon assimilation. The new coupled model is used to evaluate the impact of soil moisture availability on plant productivity for two different groups of flowering plants under different spatial configurations. • Methods In order to address different aspects of plant development due to limited soil water availability, a 3D FSP model including root, shoot, and soil was constructed by linking three different well-stablished models of airborne plant, root architecture, and reactive transport in the soil. Different parameterisation schemes were used in order to integrate photosynthetic rate with root water uptake within the coupled model. The behaviour of the model was assessed on how the growth of two different types of plants, i.e. monocot and dicot, is impacted by soil water deficit under different competitive conditions: isolated (no competition), intra, and interspecific competition. • Key Results The model proved to be capable of simulating carbon assimilation and plant development under different growing settings including isolated monocots and dicots, intra, and interspecific competition. The model predicted that (1) soil water availability has a larger impact on photosynthesis than on carbon allocation; (2) soil water deficit has an impact on root and shoot biomass production by up to 90 % for monocots and 50 % for dicots; and (3) the improved dicot biomass production in interspecific competition was highly related to root depth and plant transpiration. • Conclusions An integrated model of 3D shoot architecture and biomass development with a 3D root system representation, including light limitation and water uptake considering soil hydraulics, was presented. Plant-plant competition and regulation on stomatal conductance to drought were able to be predicted by the model. In the cases evaluated here, water limitation impacted plant growth almost 10 times more than the light environment

Costs of Conjunctivitis Outbreak, Réunion Island, France

During January–April 2015, a major outbreak of conjunctivitis on Réunion Island caused a large public health impact. On the basis of general practitioner consultations, emergency department visits, and eye medication sales during the 13-week epidemic, we estimated a total healthcare cost of €3,341,191 from the outbreak

Processes controlling phosphate acquisition by plants as revealed by coupled root system-reactive transport modeling

National audienc