Herpetofauna associada à bromélia rupícola, encholirium spectabile, no semiárido brasileiro: revisão da literatura, ecologia das espécies e comportamento de psychosaura agmosticha (squamata: mabuyidae)

Bromeliads are an important microhabitat for the herpetofauna, for being widely used as refuge from predators and their leaf architecture allows humidity maintenance and relatively constant temperature inside, setting a favorable environment for amphibians and reptiles, especially in areas under hydric stress. However, studies addressing this relationship are still incipient and more concentrated in fitotelmatas bromeliad. For non-fitotelmatas rupicolous bromeliads of the gender Encholirium, which develops into rocky outcrops and contains species of semi-arid regions such as the Caatinga, animal-plant relationships are almost unknown. In this context, this study aimed to know the herpetological fauna inhabitant of macambiras bromeliads, Encholirium spectabile, analyzing occupation and use of these bromeliads by different taxa, and the behavioral ecology of the lizard Psychosaura agmosticha, seeking to identify factors associated with this strict relationship in Caatinga. An extensive review of the world literature on the subject “lizards in bromeliads” subsidized this study from the ecological perspective of this association. The field work was carried out at Fazenda Tanques, municipality of Santa Maria / RN, mesoregion of Agreste Potiguar. The observations and/or data collection in daytime and in the evening was conducted monthly during three consecutive days, from January 2011 to August 2012, totaling 450 hour.man of sampling effort. Sixteen species were registered: six lizards (Mabuyidae, Tropiduridae, Gekkonidae and Phyllodactylidae Families), six snakes (Boidae and Dipsadidae Families) and four of amphibians of Hylidae Family. The effect of the forest edge on the distribution of species along the outcrop was significant, with most species found in outcrop edges. Significant difference was found between some pairs of species concerning use of bromeliads, and almost total niche overlap in the use of microhabitat. 62.5% of the species are nocturnal and use these plants for sheltering, breeding and feeding. Regarding the relations between 4 the lizard Psychosaura agmosticha and macambiras bromeliads, behaviors of thermoregulation and foraging in the dry and wet seasons were recorded. Activity periods were concentrated between 7 and 10 am and between 3 and 5 pm in both seasons, showing a clear bimodal pattern. The species basically used the green leaves and there were no significant differences between males and females in the use of bromeliads. Positive associations were found between body temperature and temperatures of bromeliads and air. This species spent 1.95% ± 3.8 of the time moving (PTM) and moved on average 0:36 ± 2.1 seconds per minute (MPM), with significant differences between the wet and dry to PTM, and between the average time of stop and average duration of movements, being considered a sedentary forager. Psychosaura agmosticha, in the study area, is bromelicolous and uses macambiras primarily for thermoregulation and foraging. The results of this study elevate the rupicolous bromeliads Encholirium spectabile as key elements for the maintenance of amphibians and reptiles associated with it, and a clear advantageous association for the conservation of the groups involved.

Estrutura crustal e mantélica da província Borborema através de funções do receptor e dispersão de ondas superficiais

The Borborema Province, located in northeastern Brazil, has a basement of Precambrian age and a tectonic framework structured at the Neoproterozoic (740-560 Ma). After separation between South America and Africa during the Mesozoic, a rift system was formed, giving rise to a number of marginal and inland basins in the Province. After continental breakup, episodes of volcanism and uplift characterized the evolution of the Province. Plateau uplift was initially related to magmatic underplating of mafic material at the base of the crust, perhaps related to the generation of young continental plugs (45-7 Ma) along the Macau-Queimadas Alignment (MQA), due to a small-scale convection at the continental edge. The goal of this study is to investigate the causes of intra-plate uplift and its relationship to MQA volcanism, by using broadband seismology and integrating our results with independent geophysical and geological studies in the Borborema Province. The investigation of the deep structure of the Province with broadband seismic data includes receiver functions and surface-wave dispersion tomography. Both the receiver functions and surface-wave dispersion tomography are methods that use teleseismic events and allow to develop estimates of crustal parameters such as crustal thickness, Vp/Vs ratio, and S-velocity structure. The seismograms used for the receiver function work were obtained from 52 stations in Northeast Brazil: 16 broadband stations from the RSISNE network (Rede Sismográfica do Nordeste do Brasil), and 21 short-period and 6 broadband stations from the INCT-ET network (Instituto Nacional de Ciência e Tecnologia – Estudos Tectônicos). These results add signifi- cantly to previous datasets collected at individual stations in the Province, which include station RCBR (GSN - Global Seismic Network), stations CAUB and AGBL (Brazilian Lithosphere Seismic Project IAG/USP), and 6 other broadband stations that were part of the Projeto Milênio - Estudos geofísicos e tectônicos na Província Borborema/CNPq. For the surface-wave vii tomography, seismograms recorde at 22 broadband stations were utilized: 16 broadband stations from the RSISNE network and 6 broadband stations from the Milênio project. The new constraints developed in this work include: (i) estimates of crustal thickness and bulk Vp/Vs ratio for each station using receiver functions; (ii) new measurements of surfassewave group velocity, which were integrated to existing measurementes from a continental-scale tomography for South America, and (iii) S-wave velocity models (1D) at various locations in the Borborema Province, developed through the simultaneous inversion of receiver functions and surface-wave dispersion velocities. The results display S-wave velocity structure down to the base of the crust that are consistent with the presence of a 5-7.5 km thick mafic layer. The mafic layer was observed only in the southern portion of the Plateau and absent in its northern portion. Another important observation is that our models divide the plateau into a region of thin crust (northern Plateau) and a region of thick crust (southern Plateau), confirming results from independent refraction surveys and receiver function analyses. Existing models of plateau uplift, nonetheless, cannot explain all the new observations. It is proposed that during the Brazilian orogeny a layer of preexisting mafic material was delaminated, as a whole or in part, from the original Brasiliano crust. Partial delamination would have happened in the southern portion of the plateau, where independent studies found evidence of a more resistant rheology. During Mesozoic rifting, thinning of the crust around the southern Plateau would have formed the marginal basins and the Sertaneja depression, which would have included the northern part of the Plateau. In the Cenozoic, uplift of the northern Plateau would have occurred, resulting in a northern Plateau without mafic material at the base of the crust and a southern Plateau with partially delaminated mafic layer.

Assinatura estrutural e geofísica da porção norte (fronteira Ceará-Piauí) no lineamento transbrasiliano: reativação na bacia do Parnaíba

The Transbrasiliano Lineament is a major shear zone trending NE-SW, related to the Brasiliano orogeny and evolved through high to low temperature stages. In this study, the structural and geophysical signature of the northern segment of Transbrasiliano Lineament was studied in its northern border, between Ceará and Piauí states, involving the Brasiliano mylonite zone, the Jaibaras Graben and reactivations affecting the sedimentary sequences post-ordovician of Parnaíba Basin. In the literature, is commonly the phanerozoic reactivation of this structure referred, generating several late Brasiliano grabens predating the paleozoic Parnaíba syneclises, like the Jaibaras Graben. Faults that cut the stratigraphic units of the Parnaíba Basin along the entire length of the Transbrasiliano Lineament express its reactivation during younger events. The magnetic anomaly field reduced to the pole map exhibit anomalies NE-trending, interpreted as the signature of the Transbrasiliano Lineament (and Brasiliano structures of the Borborema Province) in its high-temperature expression. The Jaibaras Graben is marked by a straight anomalous track with high magnetic susceptibility (interpreted as a prevalence of ferromagnesian rocks, probably volcanic), apparently without significant continuity in the substrate of Parnaíba Basin. The geometric and kinematic analysis of the structures in the study area, using remote sensing and field data, led to the characterization of four deformation phases brittle the ductilebrittle Dn, D1, D2 and D3. The Dn deformation phase of ediacaran-cambrian age, occurs exclusively in the Jaibaras Graben, with the development of comparatively higher temperature (as regards to younger events) ductile-brittle structures. D1, D2 and D3 deformation phases affect both the Jaibaras Graben as well as the paleozoic sequences of the northeastern edge of Parnaíba Basin, generating structures developed at lower temperatures, basically brittle/cataclastic. The SRTM image analysis allowed mapping different NE, NW and E-W trending lineaments in Parnaíba Basin, whose correlation with mesoscopic structures is discussed in terms of the reactivation of Transbrasiliano Lineament in association with the stages of general Atlantic opening and separation between South America and Africa, or even the distal orogenic events in Paleozoic.

Finding the way home: movement of butterflies in non-familiar habitats

Paisagens naturais tem sido afetadas dramaticamente pela perda de habitat e fragmentação, os quais transformam paisagens contínuas em manchas de habitat circundadas por áreas de não-habitat (matrizes). Essas matrizes, inóspitas ou não, afetam incontáveis processos ecológicos, como a dispersão. Uma das formas de compreender o efeito da matriz no processo de dispersão é estudando o alcance da percepção do habitat dos animais, o qual é definido como o alcance (distância) em que um animal pode perceber elementos da paisagem. Essa percepção está diretamente relacionada ao sucesso de chegada à um novo habitat, enquanto o animal navega por uma matriz. Nós avaliamos a percepção do habitat em Heliconius erato, uma borboleta tropical. Entretanto nós também estávamos interessados em avaliar o efeito da idade das borboletas e do tipo de matriz na percepção do habitat. Consequentemente, nós criamos borboletas em laboratório e pareamos com borboletas coletadas na floresta durante um experimento de soltura. Para determinar o alcance da percepção, nós realizamos solturas em duas diferentes matrizes (coqueiral e campo em regeneração) à três distâncias da floresta (0,30 e 100 metros) e medimos o ângulo final alcançado pelas borboletas. Nós encontramos que (I) borboletas soltas na borda se orientaram fortemente para a floresta; (II) quanto maior a distância de soltura, menor a habilidade de perceber o habitat e (III) há interação entre matriz e idade da borboleta. Borboletas inexperientes se orientaram melhor no campo aberto (alcance da percepção: 30-100 metros) e experientes se orientaram melhor no coqueiral (alcance da percepção entre 30-100 metros).

Mapeamento das projeções retinianas para o sistema óptico acessório, colículo superior e complexo pré-tectal do sagui (callithrix jacchus)

The accessory optical system, the pretectal complex, and superior colliculus are important control centers in a variety of eye movement, being extremely necessary for image formation, consequently to visual perception. The accessory optical system is constituted by the nuclei: dorsal terminal nucleus, lateral terminal nucleus, medial terminal nucleus and interstitial nucleus of the posterior superior fasciculus. From a functional point of view they contribute to the image stabilization, participating in the visuomotor activity where all system cells respond to slow eye movements and visual stimuli, which is important for the proper functioning of other visual systems. The pretectal complex comprises a group of nuclei situated in mesodiencephalic transition, they are: anterior pretectal nucleus, posterior pretectal nucleus, medial pretectal nucleus, olivary pretectal nucleus and the nucleus of the optic tract, all retinal projection recipients and functionally are related to the route of the pupillary light reflex and the optokinetic nystagmus. The superior colliculus is an important subcortical visual station formed by layers and has an important functional role in the control of eye movements and head in response to multisensory stimuli. Our aim was to make a mapping of retinal projections that focus on accessory optical system, the nuclei of pretectal complex and the superior colliculus, searching mainly for pretectal complex, better delineation of these structures through the anterograde tracing with the B subunit of cholera toxin (CTb) followed by immunohistochemistry and characterized (measured diameter) synaptic buttons present on the fibers / terminals of the nucleus complex pré-tectal. In our results accessory optical system, including a region which appears to be medial terminal nucleus and superior colliculus, were strongly marked by fibers / terminals immunoreactive CTb as well as pretectal complex in the nucleus: optic tract, olivary pretectal nucleus, anterior pretectal nucleus and posterior pretectal nucleus. According to the characterization of the buttons it was possible to make a better definition of these nucleus.

Estudo e aplicação da transformada de Fourier na regularização de dados sísmicos na exploração de petróleo

In the oil prospection research seismic data are usually irregular and sparsely sampled along the spatial coordinates due to obstacles in placement of geophones. Fourier methods provide a way to make the regularization of seismic data which are efficient if the input data is sampled on a regular grid. However, when these methods are applied to a set of irregularly sampled data, the orthogonality among the Fourier components is broken and the energy of a Fourier component may "leak" to other components, a phenomenon called "spectral leakage". The objective of this research is to study the spectral representation of irregularly sampled data method. In particular, it will be presented the basic structure of representation of the NDFT (nonuniform discrete Fourier transform), study their properties and demonstrate its potential in the processing of the seismic signal. In this way we study the FFT (fast Fourier transform) and the NFFT (nonuniform fast Fourier transform) which rapidly calculate the DFT (discrete Fourier transform) and NDFT. We compare the recovery of the signal using the FFT, DFT and NFFT. We approach the interpolation of seismic trace using the ALFT (antileakage Fourier transform) to overcome the problem of spectral leakage caused by uneven sampling. Applications to synthetic and real data showed that ALFT method works well on complex geology seismic data and suffers little with irregular spatial sampling of the data and edge effects, in addition it is robust and stable with noisy data. However, it is not as efficient as the FFT and its reconstruction is not as good in the case of irregular filling with large holes in the acquisition.

Estudo e aplicação da transformada de Fourier na regularização de dados sísmicos na exploração de petróleo

In the oil prospection research seismic data are usually irregular and sparsely sampled along the spatial coordinates due to obstacles in placement of geophones. Fourier methods provide a way to make the regularization of seismic data which are efficient if the input data is sampled on a regular grid. However, when these methods are applied to a set of irregularly sampled data, the orthogonality among the Fourier components is broken and the energy of a Fourier component may "leak" to other components, a phenomenon called "spectral leakage". The objective of this research is to study the spectral representation of irregularly sampled data method. In particular, it will be presented the basic structure of representation of the NDFT (nonuniform discrete Fourier transform), study their properties and demonstrate its potential in the processing of the seismic signal. In this way we study the FFT (fast Fourier transform) and the NFFT (nonuniform fast Fourier transform) which rapidly calculate the DFT (discrete Fourier transform) and NDFT. We compare the recovery of the signal using the FFT, DFT and NFFT. We approach the interpolation of seismic trace using the ALFT (antileakage Fourier transform) to overcome the problem of spectral leakage caused by uneven sampling. Applications to synthetic and real data showed that ALFT method works well on complex geology seismic data and suffers little with irregular spatial sampling of the data and edge effects, in addition it is robust and stable with noisy data. However, it is not as efficient as the FFT and its reconstruction is not as good in the case of irregular filling with large holes in the acquisition.

The influence of interhemispheric connections on ongoing and evoked orientation preference maps and spiking activity in the cat primary visual cortex

In the primary visual cortex, neurons with similar physiological features are clustered together in columns extending through all six cortical layers. These columns form modular orientation preference maps. Long-range lateral fibers are associated to the structure of orientation maps since they do not connect columns randomly; they rather cluster in regular intervals and interconnect predominantly columns of neurons responding to similar stimulus features. Single orientation preference maps – the joint activation of domains preferring the same orientation - were observed to emerge spontaneously and it was speculated whether this structured ongoing activation could be caused by the underlying patchy lateral connectivity. Since long-range lateral connections share many features, i.e. clustering, orientation selectivity, with visual inter-hemispheric connections (VIC) through the corpus callosum we used the latter as a model for long-range lateral connectivity. In order to address the question of how the lateral connectivity contributes to spontaneously generated maps of one hemisphere we investigated how these maps react to the deactivation of VICs originating from the contralateral hemisphere. To this end, we performed experiments in eight adult cats. We recorded voltage-sensitive dye (VSD) imaging and electrophysiological spiking activity in one brain hemisphere while reversible deactivating the other hemisphere with a cooling technique. In order to compare ongoing activity with evoked activity patterns we first presented oriented gratings as visual stimuli. Gratings had 8 different orientations distributed equally between 0º and 180º. VSD imaged frames obtained during ongoing activity conditions were then compared to the averaged evoked single orientation maps in three different states: baseline, cooling and recovery. Kohonen self-organizing maps were also used as a means of analysis without prior assumption (like the averaged single condition maps) on ongoing activity. We also evaluated if cooling had a differential effect on evoked and ongoing spiking activity of single units. We found that deactivating VICs caused no spatial disruption on the structure of either evoked or ongoing activity maps. The frequency with which a cardinally preferring (0º or 90º) map would emerge, however, decreased significantly for ongoing but not for evoked activity. The same result was found by training self-organizing maps with recorded data as input. Spiking activity of cardinally preferring units also decreased significantly for ongoing when compared to evoked activity. Based on our results we came to the following conclusions: 1) VICs are not a determinant factor of ongoing map structure. Maps continued to be spontaneously generated with the same quality, probably by a combination of ongoing activity from local recurrent connections, thalamocortical loop and feedback connections. 2) VICs account for a cardinal bias in the temporal sequence of ongoing activity patterns, i.e. deactivating VIC decreases the probability of cardinal maps to emerge spontaneously. 3) Inter- and intrahemispheric long-range connections might serve as a grid preparing primary visual cortex for likely junctions in a larger visual environment encompassing the two hemifields.

The influence of interhemispheric connections on ongoing and evoked orientation preference maps and spiking activity in the cat primary visual cortex

In the primary visual cortex, neurons with similar physiological features are clustered together in columns extending through all six cortical layers. These columns form modular orientation preference maps. Long-range lateral fibers are associated to the structure of orientation maps since they do not connect columns randomly; they rather cluster in regular intervals and interconnect predominantly columns of neurons responding to similar stimulus features. Single orientation preference maps – the joint activation of domains preferring the same orientation - were observed to emerge spontaneously and it was speculated whether this structured ongoing activation could be caused by the underlying patchy lateral connectivity. Since long-range lateral connections share many features, i.e. clustering, orientation selectivity, with visual inter-hemispheric connections (VIC) through the corpus callosum we used the latter as a model for long-range lateral connectivity. In order to address the question of how the lateral connectivity contributes to spontaneously generated maps of one hemisphere we investigated how these maps react to the deactivation of VICs originating from the contralateral hemisphere. To this end, we performed experiments in eight adult cats. We recorded voltage-sensitive dye (VSD) imaging and electrophysiological spiking activity in one brain hemisphere while reversible deactivating the other hemisphere with a cooling technique. In order to compare ongoing activity with evoked activity patterns we first presented oriented gratings as visual stimuli. Gratings had 8 different orientations distributed equally between 0º and 180º. VSD imaged frames obtained during ongoing activity conditions were then compared to the averaged evoked single orientation maps in three different states: baseline, cooling and recovery. Kohonen self-organizing maps were also used as a means of analysis without prior assumption (like the averaged single condition maps) on ongoing activity. We also evaluated if cooling had a differential effect on evoked and ongoing spiking activity of single units. We found that deactivating VICs caused no spatial disruption on the structure of either evoked or ongoing activity maps. The frequency with which a cardinally preferring (0º or 90º) map would emerge, however, decreased significantly for ongoing but not for evoked activity. The same result was found by training self-organizing maps with recorded data as input. Spiking activity of cardinally preferring units also decreased significantly for ongoing when compared to evoked activity. Based on our results we came to the following conclusions: 1) VICs are not a determinant factor of ongoing map structure. Maps continued to be spontaneously generated with the same quality, probably by a combination of ongoing activity from local recurrent connections, thalamocortical loop and feedback connections. 2) VICs account for a cardinal bias in the temporal sequence of ongoing activity patterns, i.e. deactivating VIC decreases the probability of cardinal maps to emerge spontaneously. 3) Inter- and intrahemispheric long-range connections might serve as a grid preparing primary visual cortex for likely junctions in a larger visual environment encompassing the two hemifields.

Petrologia e geologia estrutural do plutão granítico Barcelona, província Borborema, NE do Brasil

The Dissertation aimed to advance the geological knowledge of the Barcelona Granitic Pluton (BGP). This body is located in the eastern portion of the Rio Grande do Norte Domain (RND), within the São José do Campestre subdomain (SJC), NE of the Borborema Province. The main goal was to understand the geological evolution of the rocks of the pluton and the tectonic setting of magma generation and its emplacement. The BGP has an assumed Ediacaran age and outcropping area of approximately 260 km2, being composed of three varied petrographic/textural facies: (a) porphyritic biotite monzogranite; (b) dykes and sheets of biotite microgranite; (c) dioritic to quartz-dioritic enclaves. The rocks of the BGP have the following structures: (i) a NE-SW and NW-SE directed magmatic fabric (Sγ), accompanied by a magmatic lineation (Lγ) with gentle dip to NE-SW and NW-SE. In the southern portion, there is the concentric pattern of this foliation with medium to high dip, and (ii) a solid state foliation, in part mylonitic (S3+), mainly on the eastern edge with slightly plunging to west. The integration of structural and gravity data permitted to interpret the emplacement of the BGP as controlled by the transcurrent shear zones systems Lajes Pintadas (LPSZ) and Sítio Novo (SNSZ), both of dextral strike-slip kinematics. Mineral chemistry data show that the amphibole form the porphyritic biotite monzogranite facies is hastingsite with moderate Mg / (Mg + Fe) ratios, indicating crystallization under moderate to high ƒO2 and cristallization pressure of around 5.0-6.0 kbar. The biotite tends to be slightly richer in annite molecule and plots in the transitional field from primary biotite to reequilibrated biotite. In discriminant diagrams of magmatic series, the biotite behave like those of subalkaline affinity, consistent with the potassium calc-alkaline / sub-alkaline geochemical affinity of the hosting rock. The opaque minerals are primarily magnetite, with some crystals martitized to hematite indicating relatively oxidizing conditions during magma evolution that originated the BGP. Zoning in plagioclase, K-feldspar and allanite crystals suggest fractional crystallization process. Lithogeochemical data suggest that the facies described for the BGP have similar magma source, usually plotting in the fields and trends of the subalkaline / high potassium calc-alkaline series.

Evolução morfotectônica da porção centro-sul da Bacia Paraíba

Recent endogenous processes provide dynamic movements in the lithosphere and generate the varied forms of relief, even in areas of passive continental margins, such as the research area of this work located in northeastern Brazil. The reactivation of Precambrian basement structures, after the breakup between South America and Africa in the Cretaceous played an important role in the evolution of basins, which provided generated forms of relief. These morphodynamic characteristics can be easily observed in marginal basins that exhibit strong evidence fault reactivations. The purpose of this study is to investigate the influence of morphotectonic processes in the landscape structuring of Paraíba Basin. Therefore, we used aeromagnetic, high–resolution images of the Shuttle Radar Topographic Mission–SRTM, structural geological data, deep well data and geological field data. Based on the results of the data was observed that some preexisting structures in the crystalline basement coincide with magnetic and topographic lineaments interpreted as fault reactivation of the Post–Miocene units in the Paraíba Basin. Faults that offset lithostratigraphic units provided evidence that tectonic activity associated with the deposition and erosion in the Paraíba Basin occurred from Cretaceous to the Quaternary. The neotectonic activity that occurred in Paraíba Basin was able to influence the deposition of sedimentary units and landforms. It indicates that the deposition of post–Cretaceous units was influenced by reactivation of Precambrian basement structures in this part of the Brazilian continental margin.

Morfometria dos forames mandibular, mentual e infraorbital de Lobo-guará Chrysocyon brachyurus, Illiger, 1815 aplicada a bloqueios anestésicos

CHAPTER II - The Chrysocyon brachyurus is the biggest South American canid which has a high frequency of dental injuries, both in wild and captivity. Thus, veterinary procedures are necessary to preserve the feeding capacity of hundreds of captive specimens worldwide. The aim of this study was to study the mandibular morphometry of maned wolf with emphasis on the establishment of anatomic references to the anesthetic blockage of the inferior alveolar and mental nerves. Therefore, 15 measurements in 22 hemimandibles of C. brachyurus adults were taken. For extra-oral technique of blockage of the inferior alveolar nerve at the level of the mandibular foramen, it is stated that the needle should be advanced, close to the medial surface of the mandibular ramus, by 11.4 mm perpendiculary from the palpable concavity. Alternatively, the needle can be introduced for 30.4 mm from the angular process at 20-25 degrees angle with the ventral margin. For blocking only the mentual nerve, it is recommended the introduction of needle for 10 mm, close to the lateral aspect of the mandibular body, at the level of the lower first premolar. The mandibular foramen showed similars position, size and symmetry in the maned wolfs specimens examined. The comparison of the data with those available for other carnivores reflects the necessity for determining these anatomical references specifically for each species.

Simulação computacional de materiais bidimensionais: funcionalização de defeitos extensos no grafeno e retenção de contaminantes por argilominerais

In this work are considered two bidimensional systems, with distints chacacteristcs and applicabilitys. Is studied the adsorption of transition metals (MT) Fe, Co, Mn and Ru in extended defects, formed by graphene grain boundaries. First in pristine graphene The hollow site of carbon hexagon, in pristine graphene, are the most stable for MT adsorption. The Dirac cone in eletronic structure of graphene was manteined with the presence of MT. For the considered grain boundaries the MT has a greater stability for absorption in the grain boundaries sites in comparison with pristine graphene. Through the energy barrier values, are observed diffusion chanels for MT localized on the grain boundaries. This diffusion chanels indicate a possible formation of nanolines of MT in graphene. For the first stage of the nanolines, ate observed a better stability for the system with greater MT concentration, due to MT-MT interactions. Also, due to the magnetic moment of the MT, the nanolines show a magnetization. For the most stable configurations the system are metallics, particularly for Fe the band structure indicates an anisotropic spin current. In a second study, are considereted the retention capacity for metallic contaminants Cd and Hg in clayminerals, kaolinite (KAO) and montmorillonite (MMT). Through the adsorption energies of contaminantes in the clayminerals, was observed a increase in stability with the increase of contaminants concentration, due to the interaction Cd-Cd and Hg-Hg. Also, was observed that KAO has a strong interaction beteween monolayers than MMT. In this sence, for the adsoption process of contaminantes in the natural form of KAO and MMT, the latter has a better retention capacity, due to the small net work for contaminant intercalation. However, when the modification of clayminerals, with molecules that increase the spacing between monolayers, exist a optimal condition, which the contaminant absorption are more stable in KAO system than in MMT. In the Langmuir adsorption model for the clayminerals in the optimal monolayer spacing, the retention capacity for Cd and Hg in KAO system are 21% greater than in MMT system. Also, for the X-ray Absorption Near Edge Spectroscopy (XANES) for the K edge of Cd and Hg, are found a positive shift of absorption edge with the decreasing of monolayer spacing. This result indicates a possible way to determine the concentration of adsorbed contaminats in relation to unabsorbed ones, from the decomposition of experimental XANES in the obteined spectras.

Introducción al kettlebell deportivo

En el presente trabajo intentaré indagar en el kettlebell deportivo o girevoy sport (GS), un deporte de fuerza-resistencia que "fue oficialmente declarado como "el" deporte étnico de Rusia en 1974" (Sánchez, 2009), ganando popularidad luego en Europa occidental y posteriormente en el resto del mundo. Describiré su historia, antecedentes, principales características, reglamento, ejercicios particulares y algunos de sus métodos de entrenamiento

Introducción al kettlebell deportivo

En el presente trabajo intentaré indagar en el kettlebell deportivo o girevoy sport (GS), un deporte de fuerza-resistencia que "fue oficialmente declarado como "el" deporte étnico de Rusia en 1974" (Sánchez, 2009), ganando popularidad luego en Europa occidental y posteriormente en el resto del mundo. Describiré su historia, antecedentes, principales características, reglamento, ejercicios particulares y algunos de sus métodos de entrenamiento