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

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

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

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

Notes on Operations Management

Col·lecció: /obertaThe publication "Notes on Operations Management" is a document that covers different key topics in the management of production systems, organised in 11 chapters. The documents starts with the strategic aspects, and gradually and sequentially develops the more operational issues, covering aspects such as the calculation of the sales forecast, the master production shedule (MPS), the material requirement planning (MRP), stock management, project management, quality management, queue management, just-in-time, etc. Nonetheless, this is not an extensive and detailed text on the subject like most manuals in the field, but quite the opposite. It is a very concise and synthetic text, whose sole objective is to guide readers on each topic. This is why the document has been specifically called "notes". It is therefore an initial or complementary text for students who study subjects linked to "Operations Management" and who will undoubtedly need to supplement their knowledge with other resources such as the classes on the subjects, texts with solved problems, specific manuals for each topic, etcLa publicació “Notes sobre gestió de la producció” és un text que recull, en 11 capítols, diferents temàtiques clau en la gestió dels sistemes productius. Iniciant-se en els aspectes estratègics d’aquesta gestió, i de forma seqüencial, el document acaba desenvolupant els temes de caire més operatiu. Així es tracten aspectes com el càlcul de la previsió de vendes, el pla mestre de producció, la gestió de les necessitats de materials o MRP, la gestió d’estocs, la gestió de projectes, la gestió de la qualitat, la gestió de cues, el just-intime, etc. Ara bé, aquest no és un text extens i detallat al respecte, com la majoria dels manuals en la matèria, sinó justament el contrari. Es tracta d’un text molt concís i sintètic, que té com a únic objectiu orientar als lectors al respecte de cada temàtica. És per aquest fet que s’ha titulat el document específicament com a “notes”. Així doncs, aquest és un text inicial o complementari per aquells estudiants que cursen matèries vinculades a la “Gestió de la producció” i que sens dubte caldrà que complementin amb d’altres recursos com son les pròpies classes de la matèria, llibres amb problemes resolts, manuals específics per a cada temàtica, et

Notes sobre gestió de la producció

Col·lecció: /obertaLa publicació “Notes sobre gestió de la producció” és un text que recull, en 11 capítols, diferents temàtiques clau en la gestió dels sistemes productius. Iniciant-se en els aspectes estratègics d’aquesta gestió, i de forma seqüencial, el document acaba desenvolupant els temes de caire més operatiu. Així es tracten aspectes com el càlcul de la previsió de vendes, el pla mestre de producció, la gestió de les necessitats de materials o MRP, la gestió d’estocs, la gestió de projectes, la gestió de la qualitat, la gestió de cues, el just-intime, etc. Ara bé, aquest no és un text extens i detallat al respecte, com la majoria dels manuals en la matèria, sinó justament el contrari. Es tracta d’un text molt concís i sintètic, que té com a únic objectiu orientar als lectors al respecte de cada temàtica. És per aquest fet que s’ha titulat el document específicament com a “notes”. Així doncs, aquest és un text inicial o complementari per aquells estudiants que cursen matèries vinculades a la “Gestió de la producció” i que sens dubte caldrà que complementin amb d’altres recursos com son les pròpies classes de la matèria, llibres amb problemes resolts, manuals específics per a cada temàtica, etc.The publication "Notes on Operations Management" is a document that covers different key topics in the management of production systems, organised in 11 chapters. The documents starts with the strategic aspects, and gradually and sequentially develops the more operational issues, covering aspects such as the calculation of the sales forecast, the master production shedule (MPS), the material requirement planning (MRP), stock management, project management, quality management, queue management, just-in-time, etc. Nonetheless, this is not an extensive and detailed text on the subject like most manuals in the field, but quite the opposite. It is a very concise and synthetic text, whose sole objective is to guide readers on each topic. This is why the document has been specifically called "notes". It is therefore an initial or complementary text for students who study subjects linked to "Operations Management" and who will undoubtedly need to supplement their knowledge with other resources such as the classes on the subjects, texts with solved problems, specific manuals for each topic, et

The scent of fear makes sea urchins go ballistic

AbstractBackgroundClassic ecological formulations of predator–prey interactions often assume that predators and prey interact randomly in an information-limited environment. In the field, 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 urchinParacentrotus lividus, a key species in Mediterranean subtidal macrophyte communities.MethodsBehavioural experiments involved exposing a random sample ofP. lividusto either one of two treatments: (i) control water (filtered seawater) or (ii) predator-conditioned water (with cues from the mainP. lividusbenthic predator—the gastropodHexaplex trunculus). We analysed individual sea urchin trajectories, computed their heading angles, speed, path straightness, diffusive properties, and directional entropy (as a measure of path unpredictability). To account for the full picture of escaping strategies, we followed not only the first 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.ResultsThe trajectories from sea urchins subjected to predator cues were, on average, straighter and faster than those coming from controls, which translated into differences in the diffusive properties and unpredictability of their movement patterns. Sea urchins in control trials showed complex diffusive properties in an information-limited environment, with highly variable trajectories, ranging from Brownian motion to superdiffusion, and even marginal ballistic motion. In predator cue treatments, variability reduced, and trajectories became more homogeneous and predictable at the edge of ballistic motion.ConclusionsDespite 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 diffusion, 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.</jats:sec

Root diameter as predictor of born root volume – estimating the missing root characteristics in Pinus pinaster (Ait) root systems

International audienc