"El café tiene cafeína y nos despierta, nos da energía" : concepciones sobre la energía química, una buena razón para poner de acuerdo a los profesores de Física y Química y ciencias Naturales

A research was carried on students' conceptions about chemical energy. The experimental sample were students from primary level to university. Word association tasks and a paper and pencil question were used as instruments for collecting data. The test revealed that some students share certain alternative conceptions about chemical energy, and that most of them use ideas about chemical energy in a similar way to what people without formal instruction in this issue would do. Some implications for science teaching-learning are suggested

On the fringe: tracking and evaluating changes in land use in the areas surrounding three national parks in Spain and Portugal

Naturbanization analyses territorial changes in the surroundings of national parks brought about by the arrival of new settlers and economic activities, both of which are attracted by the value of the environment and landscape. This paper presents a comparison of the naturbanization processes in three national parks in Spain and Portugal (Doñana and Sierra Nevada National Parks, and Peneda-Gêres National Park, respectively) and in their areas of influence. Data is taken from Corine-Land Cover (1990-2006), which is the only available source of information about land use and land cover changes in the whole of the European Union. These changes have been interpreted and analysed using the Cross Tabulation Matrix developed by Pontius (2004). Land use changes connected to naturbanization processes are measured using Gains and Loss measurements. The intensification of changes in land use is one of the most significant developments associated with these processes, which have implications for the sustainable development and conservation of these areas

Activation and inhibition of bimanual movements in school-aged children

The development of motor activation and inhibition was compared in 6-to-12 year-olds. Children had to initiate or stop the externally paced movements of one hand, while maintaining that of the other hand. The time needed to perform the switching task (RT) and the spatio-temporal variables show different agerelated evolutions depending on the coordination pattern (inor anti-phase) and the type of transition (activation, selective inhibition, non selective inhibition) required. In the anti-phase mode, activation perturbs the younger subjects' responses while temporal and spatial stabilities transiently decrease around 9 years when activating in the in-phase mode. Aged-related changes differed between inhibition and activation in the antiphase mode, suggesting either the involvement of distinct neural networks or the existence of a single network that is reorganized. In contrast, stopping or adding one hand in the in-phase mode shows similar aged-related improvement. We suggest that selectively stopping or activating one arm during symmetrical coordination rely on the two faces of a common processing in which activation could be the release of inhibitio

Artificial Rheotaxis

Motility is a basic feature of living microorganisms, and how it works is often determined by environmental cues. Recent efforts have focused on develop- ing artificial systems that can mimic microorganisms, and in particular their self-propulsion. Here, we report on the design and characterization of syn- thetic self-propelled particles that migrate upstream, known as positive rheo- taxis. This phenomenon results from a purely physical mechanism involving the interplay between the polarity of the particles and their alignment by a viscous torque. We show quantitative agreement between experimental data and a simple model of an overdamped Brownian pendulum. The model no- tably predicts the existence of a stagnation point in a diverging flow. We take advantage of this property to demonstrate that our active particles can sense and predictably organize in an imposed flow. Our colloidal system represents an important step towards the realization of biomimetic micro-systems withthe ability to sense and respond to environmental changesComment: Published in Science Advances [Open access journal of Science Magazine

Non-uniqueness of ergodic measures with full Hausdorff dimension on a Gatzouras-Lalley carpet

In this note, we show that on certain Gatzouras-Lalley carpet, there exist more than one ergodic measures with full Hausdorff dimension. This gives a negative answer to a conjecture of Gatzouras and Peres

Gamma rays from microquasars Cygnus X-1 and Cygnus X-3

Gamma-ray observations of microquasars at high and very-high energies can provide valuable information of the acceleration processes inside the jets, the jet-environment interaction and the disk-jet coupling. Two high-mass microquasars have been deeply studied to shed light on these aspects: Cygnus X-1 and Cygnus X-3. Both systems display the canonical hard and soft X-ray spectral states of black hole transients, where the radiation is dominated by non-thermal emission from the corona and jets and by thermal emission from the disk, respectively. Here, we report on the detection of Cygnus X-1 above 60 MeV using 7.5 yr of Pass8 Fermi-LAT data, correlated with the hard X-ray state. A hint of orbital flux modulation was also found, as the source is only detected in phases around the compact object superior conjunction. We conclude that the high-energy gamma-ray emission from Cygnus X-1 is most likely associated with jets and its detection allow us to constrain the production site. Moreover, we include in the discussion the final results of a MAGIC long-term campaign on Cygnus X-1 that reaches almost 100 hr of observations at different X-ray states. On the other hand, during summer 2016, Cygnus X-3 underwent a flaring activity period in radio and high-energy gamma rays, similar to the one that led to its detection in the high-energy regime in 2009. MAGIC performed comprehensive follow-up observations for a total of about 70 hr. We discuss our results in a multi-wavelength context.Comment: Proceedings of the 35th International Cosmic Ray Conference (ICRC 2017), Bexco, Busan, Korea (arXiv:1708.05153

Wavelets techniques for pointwise anti-Holderian irregularity

In this paper, we introduce a notion of weak pointwise Holder regularity, starting from the de nition of the pointwise anti-Holder irregularity. Using this concept, a weak spectrum of singularities can be de ned as for the usual pointwise Holder regularity. We build a class of wavelet series satisfying the multifractal formalism and thus show the optimality of the upper bound. We also show that the weak spectrum of singularities is disconnected from the casual one (denoted here strong spectrum of singularities) by exhibiting a multifractal function made of Davenport series whose weak spectrum di ers from the strong one

Assessment of human influenza pandemic scenarios in Europe

The response to the emergence of the 2009 influenza A(H1N1) pandemic was the result of a decade of pandemic planning, largely centred on the threat of an avian influenza A(H5N1) pandemic. Based on a literature review, this study aims to define a set of new pandemic scenarios that could be used in case of a future influenza pandemic. A total of 338 documents were identified using a searching strategy based on seven combinations of keywords. Eighty-three of these documents provided useful information on the 13 virus-related and health-system-related parameters initially considered for describing scenarios. Among these, four parameters were finally selected (clinical attack rate, case fatality rate, hospital admission rate, and intensive care admission rate) and four different levels of severity for each of them were set. The definition of six most likely scenarios results from the combination of four different levels of severity of the four final parameters (256 possible scenarios). Although it has some limitations, this approach allows for more flexible scenarios and hence it is far from the classic scenarios structure used for pandemic plans until 2009

Lutzomyia longipalpis Saliva or Salivary Protein LJM19 Protects against Leishmania braziliensis and the Saliva of Its Vector, Lutzomyia intermedia

Leishmaniasis, caused by parasitic protozoa Leishmania, is transmitted by bites of female sand flies that, during blood-feeding, inject humans with parasites and saliva. Sand fly saliva has been investigated as a potential vaccine candidate. It was previously shown that immunization with Lutzomyia longipalpis saliva or salivary proteins protects against cutaneous and visceral leishmaniasis. In the present study, we evaluated if immunization with Lu. longipalpis saliva or DNA plasmid coding for a specific sand fly salivary protein (LJM19) can protect hamsters against L. braziliensis plus another sand fly saliva. Immunization with saliva or LJM19 DNA plasmid induced a mononuclear cell infiltrate which can be a marker of protection. The immune response induced by immunization with these insect molecules was able to protect animals against L. braziliensis infection as shown by the significant reduction in lesion size, parasite load in the ear and draining lymph node. These data show the important role of immune response against sand fly saliva components, suggesting the possibility to develop vaccines using a single component of saliva against Leishmania transmitted by different vectors