659 research outputs found

    The Occurrence of Laminarionema elsbetiae (Phaeophyceae) on Rhodymenia pseudopalmata (Rhodophyta) from the Patagonian Coasts of Argentina: Characteristics of the Relationship in Natural and Experimental Infections, and Morphology of the Epi-endophyte in Unialgal Free Cultures

    Get PDF
    The occurrence of Laminarionema elsbetiae (Ectocarpaceae, Phaeophyceae), as epi-endophyte of Rhodymenia pseudopalmata (Rhodymeniales, Rhodophyta), described from Santa Isabel, Rawson, Argentina. L. elsbetiae grows in the host tissues forming epi-endophytic relationship in the epidermal, cortical and medullar layers. Epiphytic thalli of L. elsbetiae were unbranched filaments emerging from hostis surface. Reproductive structures of L. elsbetiae on the host were absent. On the contrary, free cultured individuals formed different reproductive structures. Macrozoosporangia containing a single large motile zoospore originated from vegetative cells, they were conical to cylindrical in shape, 30-50 in length and 18-20 in wide. Uniseriate plurilocular zoosporangia were cylindrical shape, 40 in length and 10-13 in wide. Sexual fusion was not seen. In mixed cultures of L. elsbetiae with R. pseudopalmata fronds, L. elsbetiae infected the host, grew as in natural host and, formed macrosporangia between host subcortical cells. Gametophytes of L. elsbetiae were filaments with diffuse growth, branched with a branch pattern alternate or opposite. Gametangia were plurilocular, uni or biseriate and lateral. When mature they contained 2 to 6 isogametes. The presence L. elsbetiae on R. pseudopalmata could be defined as an epi-endophytic relationship. The percentage of infection of R. pseudopalmata thalli by L. elsbetiae was 34%.A25% of the infected thalli presented a low, non-symptomatic level infection, whereas a 62% and a 13% of them exhibited respectively moderate and high indexes of infection.Fil: Gauna, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Parodi, Elisa Rosalia. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Caceres, Eduardo Jorge. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Ficología y Micología; Argentin

    A LITERATURE REVIEW ON THE CURRENT STATE OF SECURITY AND PRIVACY OF MEDICAL DEVICES AND SENSORS WITH BLUETOOTH LOW ENERGY

    Get PDF
    Technology use in healthcare is an integral part of diagnosis and treatment. The use of technology in medical devices and sensors is growing. These devices include implantable medical devices, and consumer health and fitness tracking devices and applications. Bluetooth Low Energy (BLE) is the most commonly used communication method in medical devices and sensors. Security and privacy are important, especially in healthcare technologies that can impact morbidity. There is an increasing need to evaluate the security and privacy of healthcare technology, especially with devices and sensors that use Bluetooth Low Energy due to the increasing prevalence and use of medical devices and sensors. Therefore, more robust security analysis is needed to evaluate security and privacy aspects of medical devices and sensors that use Bluetooth Low Energy

    Microscopic approach of a time elapsed neural model

    Get PDF
    The spike trains are the main components of the information processing in the brain. To model spike trains several point processes have been investigated in the literature. And more macroscopic approaches have also been studied, using partial differential equation models. The main aim of the present article is to build a bridge between several point processes models (Poisson, Wold, Hawkes) that have been proved to statistically fit real spike trains data and age-structured partial differential equations as introduced by Pakdaman, Perthame and Salort

    Beyond blow-up in excitatory integrate and fire neuronal networks: refractory period and spontaneous activity

    Get PDF
    International audienceThe Network Noisy Leaky Integrate and Fire equation is among the simplest model allowing for a self-consistent description of neural networks and gives a rule to determine the probability to find a neuron at the potential vv. However, its mathematical structure is still poorly understood and, concerning its solutions, very few results are available. In the midst of them, a recent result shows blow-up in finite time for fully excitatory networks. The intuitive explanation is that each firing neuron induces a discharge of the others; thus increases the activity and consequently the discharge rate of the full network. In order to better understand the details of the phenomena and show that the equation is more complex and fruitful than expected, we analyze further the model. We extend the finite time bow-up result to the case when neurons, after firing, enter a refractory state for a given period of time. We also show that spontaneous activity may occur when, additionally, randomness is included on the firing potential VFV_F in regimes where blow-up occurs for a fixed value of VFV_F

    ANÁLISIS DEL LIDERAZGO FEMENINO Y PODER ACADÉMICO EN EL CONTEXTO UNIVERSITARIO ESPAÑOL

    Get PDF
    Although the integration of women in public life has been increasing in recent years still show difficulties in accessing senior or academic power positions in various fields, such as education. In this paper, this situation is analyzed from the conception of gender; as well as external and internal barriers to progress your career; questioning the existence of a possible female leadership in the low representation in positions of power and its link to a transformational style that must be developed from the organizational culture of schools itself, strengthening the balance in intergender relationship

    Fast quantum gates based on Landau-Zener-St\"uckelberg-Majorana transitions

    Full text link
    Fast quantum gates are of paramount importance for enabling efficient and error-resilient quantum computations. In the present work we analyze Landau-Zener-St\"uckelberg-Majorana (LSZM) strong driving protocols, tailored to implement fast gates with particular emphasis on small gap qubits. We derive analytical equations to determine the specific set of driving parameters for the implementation of single qubit and two qubit gates employing single period sinusoidal pulses. Our approach circumvents the need to scan experimentally a wide range of parameters and instead it allows to focus in fine-tuning the device near the analytically predicted values. We analyze the dependence of relaxation and decoherence on the amplitude and frequency of the pulses, obtaining the optimal regime of driving parameters to mitigate the effects of the environment. Our results focus on the study of the single qubit Xπ2X_{\frac{\pi}{2}}, Yπ2Y_{\frac{\pi}{2}} and identity gates. Also, we propose the bSWAP\sqrt{\rm{bSWAP}} as the simplest two-qubit gate attainable through a robust LZSM driving protocol

    Multiple assessments to value wild animals in the analysis of human-wildlife relationships: A case study from the Argentine Dry Chaco

    Get PDF
    Different perceptions of wildlife are usually involved in decision-making processes on the use of environmental commons and in human choices; therefore, knowing how people value nature can enhance our understanding about human-wildlife relationships. We propose to broaden the concept of cultural value by considering the trade-offs between positive and negative nature?s contributions to people (NCP), including trade-offs influenced by near-past contexts. Field work was conducted with inhabitants of a rural community of the Dry Chaco of Argentina, aiming at knowing the importance of fauna in people´s lives. We conducted free listings and semi-structured interviews and calculated the cognitive salienceindex and five cultural value indexes (differing in the number and types of NCP categories considered). Local inhabitants were found to assess wild species by considering the satisfaction of material needs, immaterial aspects, and/or the damages that certain species may cause. The ethnospecies most widely and frequently used with material purposes in the near past and at present, and those considered the most harmful showed the highest salience values. The cultural value index that integrates both positive and negative assessments was positively correlated with cognitive salience; this relationship supports the results, showing that cognitive salience not only is conditioned by positive assessments but also captures multiple fauna assessments, including the negative ones.Fil: Tamburini, Daniela Maria. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Ecología y Recursos Naturales Renovables; ArgentinaFil: Zamudio, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Caceres, Daniel Mario. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Departamento de Desarrollo Rural; Argentin

    A dosimetry and radiobiological model for intravascular brachytherapy treatment planning with radioisotope emitting stents

    Get PDF
    The aim of this study was to develop a practical, versatile and fast dosimetry and radiobiological model for calculation of the 3D dose distribution and radiobiological effectiveness of radioactive stents. The algorithm was written in Matlab 6.5 programming language and is based on the dose point kernel convolution. The dosimetry and radiobiological model was applied for evaluation of the 3D dose distribution of 32P, 90Y, 188Re and 177Lu stents. Of the four, 32P delivers the highest dose, while 90Y, 188Re and 177Lu require high levels of activity to deliver a significant therapeutic dose in the range of 15-30 Gy. Results of the radiobiological model demonstrated that the same physical dose delivered by different radioisotopes produces significantly different radiobiological effects. This type of theoretical dose calculation can be useful in the development of new stent designs, the planning of animal studies and clinical trials, and clinical decisions involving individualized treatment plans
    corecore