2,066 research outputs found

    Dielectronic Recombination of Fe XV forming Fe XIV: Laboratory Measurements and Theoretical Calculations

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    We have measured resonance strengths and energies for dielectronic recombination (DR) of Mg-like Fe XV forming Al-like Fe XIV via N=3 -> N' = 3 core excitations in the electron-ion collision energy range 0-45 eV. All measurements were carried out using the heavy-ion Test Storage Ring at the Max Planck Institute for Nuclear Physics in Heidelberg, Germany. We have also carried out new multiconfiguration Breit-Pauli (MCBP) calculations using the AUTOSTRUCTURE code. For electron-ion collision energies < 25 eV we find poor agreement between our experimental and theoretical resonance energies and strengths. From 25 to 42 eV we find good agreement between the two for resonance energies. But in this energy range the theoretical resonance strengths are ~ 31% larger than the experimental results. This is larger than our estimated total experimental uncertainty in this energy range of +/- 26% (at a 90% confidence level). Above 42 eV the difference in the shape between the calculated and measured 3s3p(^1P_1)nl DR series limit we attribute partly to the nl dependence of the detection probabilities of high Rydberg states in the experiment. We have used our measurements, supplemented by our AUTOSTRUCTURE calculations, to produce a Maxwellian-averaged 3 -> 3 DR rate coefficient for Fe XV forming Fe XIV. The resulting rate coefficient is estimated to be accurate to better than +/- 29% (at a 90% confidence level) for k_BT_e > 1 eV. At temperatures of k_BT_e ~ 2.5-15 eV, where Fe XV is predicted to form in photoionized plasmas, significant discrepancies are found between our experimentally-derived rate coefficient and previously published theoretical results. Our new MCBP plasma rate coefficient is 19-28% smaller than our experimental results over this temperature range

    Sustainability Organic Agriculture and Livestock Production with Respect to European Union in Eastern Anatolia and East Black Sea Regions

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    The majority of farm households in Turkey and especially the Eastern Anatolia are still based on low-input semi subsistence agriculture and livestock production. Despite a slow decline in recent years, agriculture and livestock production remains a major employer in Turkey and it is a significant contributor to the country’s gross domestic product, GDP. Whist Turkey is one of the EU candidate countries, is self sufficient in food production and Turkish agriculture is poorly structured inefficient, with farming in the Eastern Anatolia being mainly subsistence farming. Yet, these traditional rural structures combined with poor access to low level of education and low level of off-farm unemployment problem makes the situation more complicated and unsustainable. The best way to promote sustainability, better and higher production of Eastern Anatolian and rural Turkey is to invest in the local people, villages through improved, continuing and effective agricultural and livestock programs in particular. Investment in human capital especially in the rural areas leads to more employment opportunities through entrepreneurship and innovation in organic agriculture and livestock production. A holistic approach to developing and improving supply chains could unlock the potential for sophisticated, state-of-the-art organic agriculture and livestock producers and businesses in the region to become EU and global players. Eastern Anatolian livestock producers and the farmers have the ambitions to take part in future progress because the region is naturally organic not by design but default. It is for sure that present potential of the region has not been fully determined and utilized. EU has greatly benefited from previous enlargements economically, politically and socially. When European Union (EU) and Turkish Government relations considered and accession of Turkey to EU would be the logical consequence of the previous accessions. The screening on chapter 11 (Agriculture and rural development) is one of the important criteria and Turkey is working on to meet these benchmarks

    Using Sat solvers for synchronization issues in partial deterministic automata

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    We approach the task of computing a carefully synchronizing word of minimum length for a given partial deterministic automaton, encoding the problem as an instance of SAT and invoking a SAT solver. Our experimental results demonstrate that this approach gives satisfactory results for automata with up to 100 states even if very modest computational resources are used.Comment: 15 pages, 3 figure

    Neural development features: Spatio-temporal development of the Caenorhabditis elegans neuronal network

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    The nematode Caenorhabditis elegans, with information on neural connectivity, three-dimensional position and cell linage provides a unique system for understanding the development of neural networks. Although C. elegans has been widely studied in the past, we present the first statistical study from a developmental perspective, with findings that raise interesting suggestions on the establishment of long-distance connections and network hubs. Here, we analyze the neuro-development for temporal and spatial features, using birth times of neurons and their three-dimensional positions. Comparisons of growth in C. elegans with random spatial network growth highlight two findings relevant to neural network development. First, most neurons which are linked by long-distance connections are born around the same time and early on, suggesting the possibility of early contact or interaction between connected neurons during development. Second, early-born neurons are more highly connected (tendency to form hubs) than later born neurons. This indicates that the longer time frame available to them might underlie high connectivity. Both outcomes are not observed for random connection formation. The study finds that around one-third of electrically coupled long-range connections are late forming, raising the question of what mechanisms are involved in ensuring their accuracy, particularly in light of the extremely invariant connectivity observed in C. elegans. In conclusion, the sequence of neural network development highlights the possibility of early contact or interaction in securing long-distance and high-degree connectivity

    Cloud-based online social network

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    International audienceOnline social media network has become part of human life by transforming the way users create new social relations or relate with family and friends. Online social network (OSN) has drastically increased the rate at which people interact with each other by simplifying the means of communication. However, privacy is raising a serious concern. All user generated data within the OSN system need to be protected against unauthorized friends or hackers or even against the provider of OSN. Many research works are going on to encounter the privacy issues in OSN. This paper analyses the limitations of the recent work being done in this field and proposes an efficient abstract solution to them

    A cost effectiveness analysis of salt reduction policies to reduce coronary heart disease in four Eastern Mediterranean countries.

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    BACKGROUND: Coronary Heart Disease (CHD) is rising in middle income countries. Population based strategies to reduce specific CHD risk factors have an important role to play in reducing overall CHD mortality. Reducing dietary salt consumption is a potentially cost-effective way to reduce CHD events. This paper presents an economic evaluation of population based salt reduction policies in Tunisia, Syria, Palestine and Turkey. METHODS AND FINDINGS: Three policies to reduce dietary salt intake were evaluated: a health promotion campaign, labelling of food packaging and mandatory reformulation of salt content in processed food. These were evaluated separately and in combination. Estimates of the effectiveness of salt reduction on blood pressure were based on a literature review. The reduction in mortality was estimated using the IMPACT CHD model specific to that country. Cumulative population health effects were quantified as life years gained (LYG) over a 10 year time frame. The costs of each policy were estimated using evidence from comparable policies and expert opinion including public sector costs and costs to the food industry. Health care costs associated with CHDs were estimated using standardized unit costs. The total cost of implementing each policy was compared against the current baseline (no policy). All costs were calculated using 2010 PPP exchange rates. In all four countries most policies were cost saving compared with the baseline. The combination of all three policies (reducing salt consumption by 30%) resulted in estimated cost savings of 235,000,000and6455LYGinTunisia;235,000,000 and 6455 LYG in Tunisia; 39,000,000 and 31674 LYG in Syria; 6,000,000and2682LYGinPalestineand6,000,000 and 2682 LYG in Palestine and 1,3000,000,000 and 378439 LYG in Turkey. CONCLUSION: Decreasing dietary salt intake will reduce coronary heart disease deaths in the four countries. A comprehensive strategy of health education and food industry actions to label and reduce salt content would save both money and lives

    Speaker-independent emotion recognition exploiting a psychologically-inspired binary cascade classification schema

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    In this paper, a psychologically-inspired binary cascade classification schema is proposed for speech emotion recognition. Performance is enhanced because commonly confused pairs of emotions are distinguishable from one another. Extracted features are related to statistics of pitch, formants, and energy contours, as well as spectrum, cepstrum, perceptual and temporal features, autocorrelation, MPEG-7 descriptors, Fujisakis model parameters, voice quality, jitter, and shimmer. Selected features are fed as input to K nearest neighborhood classifier and to support vector machines. Two kernels are tested for the latter: Linear and Gaussian radial basis function. The recently proposed speaker-independent experimental protocol is tested on the Berlin emotional speech database for each gender separately. The best emotion recognition accuracy, achieved by support vector machines with linear kernel, equals 87.7%, outperforming state-of-the-art approaches. Statistical analysis is first carried out with respect to the classifiers error rates and then to evaluate the information expressed by the classifiers confusion matrices. © Springer Science+Business Media, LLC 2011

    Interference effects in the photorecombination of argonlike Sc3+ ions: Storage-ring experiment and theory

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    Absolute total electron-ion recombination rate coefficients of argonlike Sc3+(3s2 3p6) ions have been measured for relative energies between electrons and ions ranging from 0 to 45 eV. This energy range comprises all dielectronic recombination resonances attached to 3p -> 3d and 3p -> 4s excitations. A broad resonance with an experimental width of 0.89 +- 0.07 eV due to the 3p5 3d2 2F intermediate state is found at 12.31 +- 0.03 eV with a small experimental evidence for an asymmetric line shape. From R-Matrix and perturbative calculations we infer that the asymmetric line shape may not only be due to quantum mechanical interference between direct and resonant recombination channels as predicted by Gorczyca et al. [Phys. Rev. A 56, 4742 (1997)], but may partly also be due to the interaction with an adjacent overlapping DR resonance of the same symmetry. The overall agreement between theory and experiment is poor. Differences between our experimental and our theoretical resonance positions are as large as 1.4 eV. This illustrates the difficulty to accurately describe the structure of an atomic system with an open 3d-shell with state-of-the-art theoretical methods. Furthermore, we find that a relativistic theoretical treatment of the system under study is mandatory since the existence of experimentally observed strong 3p5 3d2 2D and 3p5 3d 4s 2D resonances can only be explained when calculations beyond LS-coupling are carried out.Comment: 11 pages, 7 figures, 3 tables, Phys. Rev. A (in print), see also: http://www.strz.uni-giessen.de/~k

    Screening of DUB activity and specificity by MALDI-TOF mass spectrometry

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    Deubiquitylases (DUBs) are key regulators of the ubiquitin system which cleave ubiquitin moieties from proteins and polyubiquitin chains. Several DUBs have been implicated in various diseases and are attractive drug targets. We have developed a sensitive and fast assay to quantify in vitro DUB enzyme activity using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Unlike other current assays, this method uses unmodified substrates, such as diubiquitin topoisomers. By analyzing 42 human DUBs against all diubiquitin topoisomers we provide an extensive characterization of DUB activity and specificity. Our results confirm the high specificity of many members of the OTU and JAMM DUB families and highlight that all USPs tested display low linkage selectivity. We also demonstrate that this assay can be deployed to assess the potency and specificity of DUB inhibitors by profiling 11 compounds against a panel of 32 DUBs
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