3,849 research outputs found

    A node-wise analysis of the uterine muscle networks for pregnancy monitoring

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    The recent past years have seen a noticeable increase of interest in the correlation analysis of electrohysterographic (EHG) signals in the perspective of improving the pregnancy monitoring. Here we propose a new approach based on the functional connectivity between multichannel (4x4 matrix) EHG signals recorded from the women abdomen. The proposed pipeline includes i) the computation of the statistical couplings between the multichannel EHG signals, ii) the characterization of the connectivity matrices, computed by using the imaginary part of the coherence, based on the graph-theory analysis and iii) the use of these measures for pregnancy monitoring. The method was evaluated on a dataset of EHGs, in order to track the correlation between EHGs collected by each electrode of the matrix (called node-wise analysis) and follow their evolution along weeks before labor. Results showed that the strength of each node significantly increases from pregnancy to labor. Electrodes located on the median vertical axis of the uterus seemed to be the more discriminant. We speculate that the network-based analysis can be a very promising tool to improve pregnancy monitoring.Comment: 4 pages, 3 figures, accepted in the IEEE EMBC conferanc

    A Note on the Edge Roman Domination in Trees

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    A subset XX of edges of a graph GG is called an \textit{edgedominating set} of GG if every edge not in XX is adjacent tosome edge in XX. The edge domination number γ(G)\gamma'(G) of GG is the minimum cardinality taken over all edge dominating sets of GG. An \textit{edge Roman dominating function} of a graph GG is a function f:E(G){0,1,2}f : E(G)\rightarrow \{0,1,2 \} such that every edgeee with f(e)=0f(e)=0 is adjacent to some edge ee' with f(e)=2.f(e') = 2.The weight of an edge Roman dominating function ff is the valuew(f)=eE(G)f(e)w(f)=\sum_{e\in E(G)}f(e). The edge Roman domination number of GG, denoted by γR(G)\gamma_R'(G), is the minimum weight of an edge Roman dominating function of GG. In this paper, we characterize trees with edge Roman domination number twice the edge domination number

    The Internet Use and Community Involvement in Tehran Iran

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    This is exploring the impact of the internet on local community involvement in Tehran, Iran. It investigates how the internet changes community involvement and argues that the Internet has created new forms of community involvement instead of local community involvement. This study has employed quantitative research methods. The sample for this research was drawn from the population of Internet users, namely people who accessed and used the Internet in Tehran, Iran. The results of the study indicate that there was no significant correlation between the amount of Internet use and local community involvement. People who spend more time online (high Internet user) do not have a greater local community involvement than people who use Internet less of the time. By contrast in terms of type of Internet use and social capital the study found that people who used the Internet for local news and reading newspapers online were more involved in the local community. The study illustrated that the Internet encourages people to some extent to become involved in the national or global community.nbs

    The Effect of Herbal Essential Oil in Preservative Solution, on Quantitative, Vase Life, Bacteria-induced Stem Xylem Blockage of Lisianthus Var. Echo

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    In this study the effect of essential oil taken from medicinal plant as antibacterial components in preservative solution of Lisianthus var. Echo (Eustoma grandiflorum) was investigated. The test was done with application of preservative solution. Cut flowers were treated with different concentrations of Thyme (Thymus vulgaris), Spearmint (Mentha spicata) and Lavender (Lavandula officinalis) essential oil in addition to Sucrose 2.5%. The results showed that there was the longest time in vase life with Thyme in 50 ppm (15.6 days) and the control treatment showed the shortest vase life (11.6 days). Moreover, Thyme with 50 ppm had the highest effect on relative fresh weight and solution uptake. In addition, bacteria-induced stem xylem blockage, extracted from the end of stem, was cultured in NA medium culture with several concentrations of essential oil. The result showed that in pure concentration (100%) inhibition was completed and in various concentrations of essential oil the bacterial population was reduced

    Circuit elements at optical frequencies: nano-inductors, nano-capacitors and nano-resistors

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    We present some ideas for synthesizing nanocircuit elements in the optical domain using plasmonic and non-plasmonic nanoparticles. Three basic circuit elements, i.e., nano-inductors, nano-capacitors, and nano-resistors, are discussed in terms of small nanostructures with different material properties. Coupled nanocircuits and parallel and series combinations are also envisioned, which may provide road maps for the synthesis of more complex nanocircuits in the IR and visible bands. Ideas for the optical implementation of right-handed and left-handed nano-transmission lines are also forecasted.Comment: 14 pages, 5 figures, submitted to Physical Review Letter

    What is unpaid female labour worth? Evidence from the Time Use Studies of Iran in 2008 and 2009

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    This paper uses the Time Use Survey of Iran of 2008 and 2009 to estimate the monetary value of unpaid domestic work of urban housewives. The surveys recorded domestic work activities such as cooking and cleaning and general care of household members as well as care of children and their education. Using the market-based approach to estimate the monetary value of unpaid domestic work we collected data on the cost of buying in services for domestic work and for education of children from ‘nursing agencies’ and private education colleges in main cities of Iran in the summer of 2011 that were adjusted to obtain the 2008 and 2009 prices. The market value of domestic work of urban housewives was estimated to be US25billionin2008andUS25 billion in 2008 and US29 billion in 2009. These were about 8.6 per cent of non-oil GDP in the same years. Our estimates complement other findings from around the world that confirm substantial contribution of housewives to the economy. These contributions have gone unrecorded and not compensated in most countries. At a minimum, housewives can be insured against basic contingencies of life such has health problems, poverty and disabilities and supported in old age. Our work and other studies do provide the economic and social arguments for costing and putting into practice the long overdue support for housewives; they have earned it

    FDTD analysis of the tunneling and growing exponential in a pair of epsilon-negative and mu-negative slabs

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    Pairing together material slabs with opposite signs for the real parts of their constitutive parameters has been shown to lead to interesting and unconventional properties that are not otherwise observable for single slabs. One such case was demonstrated analytically for the conjugate (i.e., complementary) pairing of infinite planar slabs of epsilon-negative (ENG) and mu-negative (MNG) media [A. Alu, and N. Engheta, IEEE Trans. Antennas Prop., 51, 2558 (2003)]. There it was shown that when these two slabs are juxtaposed and excited by an incident plane wave, resonance, complete tunneling, total transparency and reconstruction of evanescent waves may occur in the steady-state regime under a monochromatic excitation, even though each of the two slabs by itself is essentially opaque to the incoming radiation. This may lead to virtual imagers with sub-wavelength resolution and other anomalous phenomena overcoming the physical limit of diffraction. Here we explore how a transient sinusoidal signal that starts at t = 0 interacts with such an ENG-MNG pair of finite size using an FDTD technique. Multiple reflections and transmissions at each interface are shown to build up to the eventual steady state response of the pair, and during this process one can observe how the growing exponential phenomenon may actually occur inside this bilayer.Comment: 14 pages, 9 figures, submitted to Phys Rev

    A Metamaterial-Inspired Model for Electron Waves in Bulk Semiconductors

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    Based on an analogy with electromagnetic metamaterials, we develop an effective medium description for the propagation of electron matter waves in bulk semiconductors with a zincblende structure. It is formally demonstrated that even though departing from a different starting point, our theory gives results for the energy stationary states consistent with Bastard's envelope function approximation in the long-wavelength limit. Using the proposed approach, we discuss the time evolution of a wave packet in a bulk semiconductor with a zero-gap and linear energy-momentum dispersion.Comment: 43 pages, 4 figure

    Armed conflict and human behavior: a case study of the environmental management process in North Lebanon

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    This paper examines the variation in the effects of individuals’ vulnerability and trust on human behavior within five geographical areas (Akkar, Menieh, Tripoli, Koura, Batroun) along the northern coastline of Lebanon in the context of recurring armed conflict. Lebanon has been subject to regular episodes of armed conflict since 1975, with severe impacts on the social, economic, and political levels as well as on the environment. We argue that the episodes of armed conflict have increased individuals’ vulnerability and negatively affected citizens’ trust among themselves and between them and the stakeholders in the public sector at the national level involved in the environmental management process. The findings are based on 499 questionnaire surveys among citizens in the study area, 24 structured interviews with heads or representatives of heads of the villages and cities in the study area, and secondary literature including previous studies and official documents. The findings show spatial variation of citizens’ vulnerability to environmental damage caused by armed conflict. Citizens of Akkar, Menieh, and Tripoli show higher levels of vulnerability compared with citizens of Batroun and Koura. In addition, distrust between citizens themselves and between them and public sector stakeholders was one of the results of recurring armed conflict. Lack of trust between citizens and stakeholders of public sector is particularly relevant in environmental management in Lebanon
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