Evaluation of Management Routes for the Paldiski Sarcophagi

The necessity to develop the submarine fleet in Russia required constructing a special training base for the training of submarine crews. To this purpose two prototypes of nuclear power units, close analogous to those fitting out nuclear submarines were constructed and commissioned in the sixties on the Navy training centre's base located in Paldiski (Pakri peninsula, Estonia). In 1994, nuclear fuel was discharged from the reactors and transported to Russia while the reactors themselves were prepared for prolonged storage, prior to transfer of the Paldiski facilities to the ownership of the Estonian Republic. The Paldiski facilities are currently being dismantled with the exception of two sarcophagi made of concrete that are housing the two reactor compartments. The question of the future management of both sarcophagi is a key-issue in the cleaning up of the whole Paldiski site. Actually, three basic questions should answered: when should dismantling operations occur, how this should be done, and what could be the corresponding cost. Within the context of enlargement of the European Union, the Commission services (first Directorate-General for Environment and then Directorate-General for Enlargement) decided to support Estonia to respond to these three questions through a study contract that was awarded in 1999 to a TECHNICATOME/BNFL consortium. The work scope was made up of three distinct tasks: data collection regarding the nuclear reactors and enclosing compartments design, and the works carried in order to prepare the reactor compartments for long-term storage; drawing up dismantling strategies in order to reach the third decommissioning level defined by IAEA; and evaluation of these decommissioning options on the basis cost estimation and radiological impact evaluation, in view to recommend the best management route. This article gives the key stages and the conclusions of this study

The phytosanitary status of the National Collection of fruits and nuts of Afghanistan and the private Mother Stock Nurseries: a virus survey

The horticultural industry is a vital component of the agriculture sector of Afghanistan, the primary engine of the country’s recovering economy which engages approximately 80% of the working population. This sector was thriving in the 1970s, but is today incapable of competing in the international market. To recover and develop the horticulture of the country, the European Community (EC) supports the PHDP (Perennial Horticulture Development Project), to provide true to type/ecotype and healthy planting materials, and the Plant Biotechnology Laboratory, to ensure the health status of local germplasm. This laboratory started screening the health status of the Afghan Germplasm National Collections in order to ensure the multiplication of not only the best-selected varieties or ecotype, but also to avoid production and distribution of virus-infected trees. Inspection for symptoms and sample collection for viral diseases was carried out in all the National Collection fields, including cherry, pear, peach, plum, apricot, almond, apple, grape and citrus plants, located in different areas of the country. Stone fruit plants infected by Apple chlorotic leaf spot virus or Prunus necrotic ringspot virus have been identified in the National Collection experimental farms located in different provinces of Afghanistan. Moreover, many grape plants included in the National Collection located in Herat and Kandahar resulted infected by Grapevine fanleaf virus, but only few imported plants by Grapevine leafroll associated virus 1, Grapevine leafroll associated virus 3 or Grapevine virus A. Finally, in Jalalabad (Nangarhar province) citrus plants showing vein flecking, yellowing and plant decline symptoms were found to be infected by Citrus tristeza virus. Some of the identified viral isolates have been characterized molecularly, amplifying a fragment corresponding to the coat protein gene from a selection of positive samples. The presence of those viruses in different accessions of the national collection is of concern for Afghan horticulture. Implementation of the certification schemes is therefore necessary to quarantine the production and for the employment of virus-free propagating material

The physiological variability of channel density in hippocampal CA1 pyramidal cells and interneurons explored using a unified data-driven modeling workflow

Every neuron is part of a network, exerting its function by transforming multiple spatiotemporal synaptic input patterns into a single spiking output. This function is specified by the particular shape and passive electrical properties of the neuronal membrane, and the composition and spatial distribution of ion channels across its processes. For a variety of physiological or pathological reasons, the intrinsic input/output function may change during a neuron’s lifetime. This process results in high variability in the peak specific conductance of ion channels in individual neurons. The mechanisms responsible for this variability are not well understood, although there are clear indications from experiment and modeling that degeneracy and correlation among multiple channels may be involved. Here, we studied this issue in biophysical models of hippocampal CA1 pyramidal neurons and interneurons. Using a unified data-driven simulation workflow and starting from a set of experimental recordings and morphological reconstructions obtained from rats, we built and analyzed several ensembles of morphologically and biophysically accurate single cell models with intrinsic electrophysiological properties consistent with experimental findings. The results suggest that the set of conductances expressed in any given hippocampal neuron may be considered as belonging to two groups: one subset is responsible for the major characteristics of the firing behavior in each population and the other responsible for a robust degeneracy. Analysis of the model neurons suggests several experimentally testable predictions related to the combination and relative proportion of the different conductances that should be expressed on the membrane of different types of neurons for them to fulfill their role in the hippocampus circuitry

The physiological variability of channel density in hippocampal CA1 pyramidal cells and interneurons explored using a unified data-driven modeling workflow

Every neuron is part of a network, exerting its function by transforming multiple spatiotemporal synaptic input patterns into a single spiking output. This function is specified by the particular shape and passive electrical properties of the neuronal membrane, and the composition and spatial distribution of ion channels across its processes. For a variety of physiological or pathological reasons, the intrinsic input/output function may change during a neuron’s lifetime. This process results in high variability in the peak specific conductance of ion channels in individual neurons. The mechanisms responsible for this variability are not well understood, although there are clear indications from experiment and modeling that degeneracy and correlation among multiple channels may be involved. Here, we studied this issue in biophysical models of hippocampal CA1 pyramidal neurons and interneurons. Using a unified data-driven simulation workflow and starting from a set of experimental recordings and morphological reconstructions obtained from rats, we built and analyzed several ensembles of morphologically and biophysically accurate single cell models with intrinsic electrophysiological properties consistent with experimental findings. The results suggest that the set of conductances expressed in any given hippocampal neuron may be considered as belonging to two groups: one subset is responsible for the major characteristics of the firing behavior in each population and the other responsible for a robust degeneracy. Analysis of the model neurons suggests several experimentally testable predictions related to the combination and relative proportion of the different conductances that should be expressed on the membrane of different types of neurons for them to fulfill their role in the hippocampus circuitry

Planet Hunters TESS. V. A Planetary System Around a Binary Star, Including a Mini-Neptune in the Habitable Zone

We report on the discovery and validation of a transiting long-period mini-Neptune orbiting a bright (V = 9.0 mag) G dwarf (TOI 4633; R = 1.05 R ⊙, M = 1.10 M ⊙). The planet was identified in data from the Transiting Exoplanet Survey Satellite by citizen scientists taking part in the Planet Hunters TESS project. Modelling of the transit events yields an orbital period of 271.9445 ± 0.0040 days and radius of 3.2 ± 0.20 R ⊕. The Earth-like orbital period and an incident flux of 1.56−0.16+0.20 F ⊕ places it in the optimistic habitable zone around the star. Doppler spectroscopy of the system allowed us to place an upper mass limit on the transiting planet and revealed a non-transiting planet candidate in the system with a period of 34.15 ± 0.15 days. Furthermore, the combination of archival data dating back to 1905 with new high angular resolution imaging revealed a stellar companion orbiting the primary star with an orbital period of around 230 yr and an eccentricity of about 0.9. The long period of the transiting planet, combined with the high eccentricity and close approach of the companion star makes this a valuable system for testing the formation and stability of planets in binary systems

26th Annual Computational Neuroscience Meeting (CNS*2017): Part 3 - Meeting Abstracts - Antwerp, Belgium. 15–20 July 2017

This work was produced as part of the activities of FAPESP Research,\ud Disseminations and Innovation Center for Neuromathematics (grant\ud 2013/07699-0, S. Paulo Research Foundation). NLK is supported by a\ud FAPESP postdoctoral fellowship (grant 2016/03855-5). ACR is partially\ud supported by a CNPq fellowship (grant 306251/2014-0)

Nanostructure, compositional and magnetic studies of Poly(aniline)–CoFe2O4 nanocomposites

Magnetic and conducting composites of cobalt ferrite nanoparticles and poly(aniline) have been synthesized in acid media by the oxidative polymerization of aniline in the presence of a dispersion of magnetic nanoparticles, using Fe(III) ions as an oxidizing agent. The materials have been characterized by X-ray diffraction studies, X-ray fluorescence, energy dispersive X-ray spectroscopy, thermogravimetric analysis, transmission electron microscopy, spectrum-imaging electron energy loss spectroscopy, conductivity and DC magnetization measurements. The composite composition and morphology depend on the aniline/magnetic nanoparticle molar ratio used during the synthesis; for composites with a low polymer content, poly(aniline) (PANI), growth occurs preferably in the vicinity of the magnetic nanoparticles, while for composites with a higher polymer content, the magnetic nanoparticles are embedded in the PANI matrix. It was also observed that iron is incorporated in the composites during their preparation. The electrical conductivities of all the synthesized materials have values in the range 1–100 S cm−1, i.e., in the metallic regime. Also, the composites feature good magnetic properties, with ferrimagnetic behavior for CoFe2O4 and the composites. The coercivity decreases as the PANI/ferrite ratio increases, indicating that poly(aniline) affects the magnetic anisotropy. All these results suggest that the morphology and the composition affect the magnetic behavior.Fil: Landa, Romina Ailín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Calvino, Jose J.. Universidad de Cádiz; EspañaFil: López-Haro, Miguel. Universidad de Cádiz; EspañaFil: Antonel, Paula Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentin

A Back Migration from Asia to Sub-Saharan Africa Is Supported by High-Resolution Analysis of Human Y-Chromosome Haplotypes

The variation of 77 biallelic sites located in the nonrecombining portion of the Y chromosome was examined in 608 male subjects from 22 African populations. This survey revealed a total of 37 binary haplotypes, which were combined with microsatellite polymorphism data to evaluate internal diversities and to estimate coalescence ages of the binary haplotypes. The majority of binary haplotypes showed a nonuniform distribution across the continent. Analysis of molecular variance detected a high level of interpopulation diversity (ΦST=0.342), which appears to be partially related to the geography (ΦCT=0.230). In sub-Saharan Africa, the recent spread of a set of haplotypes partially erased pre-existing diversity, but a high level of population (ΦST=0.332) and geographic (ΦCT=0.179) structuring persists. Correspondence analysis shows that three main clusters of populations can be identified: northern, eastern, and sub-Saharan Africans. Among the latter, the Khoisan, the Pygmies, and the northern Cameroonians are clearly distinct from a tight cluster formed by the Niger-Congo–speaking populations from western, central western, and southern Africa. Phylogeographic analyses suggest that a large component of the present Khoisan gene pool is eastern African in origin and that Asia was the source of a back migration to sub-Saharan Africa. Haplogroup IX Y chromosomes appear to have been involved in such a migration, the traces of which can now be observed mostly in northern Cameroon