233 research outputs found

    Heavy metal accumulation in Artemisia and foliaceous lichen species from the Azerbaijan flora

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    Artemisia plants and foliaceous lichens are known to be capable of accumulating heavy metals (HM) from soil and air. These plant species are widespread on polluted sites of Azerbaijan. However, so far their capacity to accumulate HM in their shoots and roots has not been tested. Three Artemisia and two lichen species were collected from different contaminated sites of Azerbaijan. Plant and surface soil samples were measured for Cd, Cu, Pb, Ni and Zn concentrations by ICP-AES.The results indicated that among the Artemisia species A. scoparia showed the best HM accumulation properties. Lichen species were also distinguished by very high amounts of HM in their biomass, while in surrounding soil samples HM concentrations had higher contents than the soils occupied only with Artemisia species.The results indicate that on contaminated sites Artemisia and lichens accumulated metals in their biomass without toxicity symptoms. Taking large biomass and high adaptation ability into account, A. scoparia represents a good tool for a phytoremediation approach on polluted soils

    Multiband superconductivity in the correlated electron filled skutterudite system Pr(1-x)Ce(x)Pt4Ge12

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    Studies of superconductivity in multiband correlated electronic systems has become one of the central topics in condensed matter/materials physics. In this paper, we present the results of thermodynamic measurements on the superconducting filled skutterudite system Pr1−x_{1-x}Cex_xPt4_4Ge12_{12} (0≀x≀0.2 0 \leq x \leq 0.2) to investigate how substitution of Ce at Pr sites affects superconductivity. We find that an increase in Ce concentration leads to a suppression of the superconducting transition temperature from Tc∌7.9T_{c}\sim 7.9 K for x=0x=0 to Tc∌0.6T_c\sim 0.6 K for x=0.14x=0.14. Our analysis of the specific heat data for x≀0.07x\leq 0.07 reveals that superconductivity must develop in at least two bands: the superconducting order parameter has nodes on one Fermi pocket and remains fully gapped on the other. Both the nodal and nodeless gap values decrease, with the nodal gap being suppressed more strongly, with Ce substitution. Ultimately, the higher Ce concentration samples (x>0.07x>0.07) display a nodeless gap only.Comment: 6 pages, 6 figure

    Biembeddings of cycle systems using integer Heffter arrays

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    In this paper, we use constructions of Heffter arrays to verify the existence of face 2‐colorable embeddings of cycle decompositions of the complete graph. Specifically, for n ≡ 1 (mod 4) and k ≡3(mod 4), n k ≫ â©Ÿ 7 and when n ≡ 0(mod 3) then k ≡ 7(mod 12), there exist face 2-colorable embeddings of the complete graph K₂ₙₖ₊₁ onto an orientable surface where each face is a cycle of a fixed length k. In these embeddings the vertices of K₂ₙₖ₊₁ will be labeled with the elements of Z₂ₙₖ₊₁ in such a way that the group, (Z₂ₙₖ₊₁, +) acts sharply transitively on the vertices of the embedding. This result is achieved by verifying the existence of nonequivalent Heffter arrays, H (n ; k), which satisfy the conditions: (1) for each row and each column the sequential partial sums determined by the natural ordering must be distinct modulo 2nk + 1; (2) the composition of the natural orderings of the rows and columns is equivalent to a single cycle permutation on the entries in the array. The existence of Heffter arrays H (n ; k) that satisfy condition (1) was established earlier in Burrage et al. and in this current paper, we vary this construction and show, for k â©Ÿ 11, that there are at least (n − 2)[((k − 11)/4)!/ ]ÂČ such nonequivalent H (n ; k) that satisfy both conditions (1) and (2)

    Clinical spectrum of early onset “Mediterranean” (homozygous p.P131L mutation) mitochondrial neurogastrointestinal encephalomyopathy

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    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive mitochondrial disorder characterized by cumulative and progressive gastrointestinal and neurological findings. This retrospective observational study, aimed to explore the time of presentation, diagnosis and clinical follow-up of 13 patients with a confirmed MNGIE disease of Mediterranean origin. The mean age of symptom onset was 7 years (6 months−21 years) and the average diagnosis age was 15.4 years ±8.4. Four of 13 patients (30%) died before 30 years at the mean age of 19.7 years ±6.8. Cachexia and gastrointestinal symptoms were observed in all patients (100%). The mean body mass index standard deviation score at diagnosis was 4.8 ± 2.8. At least three subocclusive episodes were presented in patients who died in last year of their life. The main neurological symptom found in most patients was peripheral neuropathy (92%). Ten patients (77%) had leukoencephalopathy and the remaining three patients without were under 10 years of age. The new homozygous “Mediterranean” TYMP mutation, p.P131L (c.392 C > T) was associated with an early presentation and poor prognosis in nine patients (69%) from five separates families. Based on the observations from this Mediterranean MNGIE cohort, we propose that the unexplained abdominal pain combined with cachexia is an indicator of MNGIE. High-platelet counts and nerve conduction studies may be supportive laboratory findings and the frequent subocclusive episodes could be a negative prognostic factor for mortality. Finally, the homozygous p.P131L (c.392 C > T) mutation could be associated with rapid progressive disease with poor prognosis

    METIS research advances towards the 5G mobile and wireless system definition

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    [EN] The Mobile and wireless communications Enablers for the Twenty-twenty Information Society (METIS) project is laying the foundations of Fifth Generation (5G) mobile and wireless communication system putting together the point of view of vendors, operators, vertical players, and academia. METIS envisions a 5G system concept that efficiently integrates new applications developed in the METIS horizontal topics and evolved versions of existing services and systems. This article provides a first view on the METIS system concept, highlights the main features including architecture, and addresses the challenges while discussing perspectives for the further research work.Part of this work has been performed in the framework of the FP7 project ICT-317669 METIS, which is partly funded by the European Commission. The authors would like to acknowledge the contributions of their colleagues in METIS with special thanks to Petar Popovski, Peter Fertl, David Gozalvez-Serrano, Andreas Hoglund, Zexian Li, and Krystian Pawlak. Also thanks to Josef Eichinger and Malte Schellmann for the fruitful discussions during the revision of this article.Monserrat Del RĂ­o, JF.; Mange, G.; Braun, V.; Tullberg, H.; Zimmermann, G.; Bulakci, O. (2015). METIS research advances towards the 5G mobile and wireless system definition. EURASIP Journal on Wireless Communications and Networking. 2015(53):1-16. https://doi.org/10.1186/s13638-015-0302-9S116201553Cisco, in Global Mobile Data Traffic Forecast Update, 2014–2019 White Paper, February 2015. http://www.cisco.com/c/en/us/solutions/collateral/service-provider/visual-networking-index-vni/white_paper_c11-520862.pdfMETIS, in Mobile and wireless communications Enablers for the Twenty-twenty Information Society, EU 7th Framework Programme project, http://www.metis2020.com .ICT-317669 METIS project, in Scenarios, requirements and KPIs for 5G mobile and wireless system, Deliverable D1.1, May 2013, https://www.metis2020.com/documents/deliverables/B Ahlgren, C Dannewitz, C Imbrenda, D Kutscher, B Ohlman, A survey of information-centric networking. IEEE Commun Mag 50(7), 26–36 (2012)A Osseiran, F Boccardi, V Braun, K Kusume, P Marsch, M Maternia, O Queseth, M Schellmann, H Schotten, H Taoka, H Tullberg, MA Uusitalo, B Timus, M Fallgren, Scenarios for the 5G mobile and wireless communications: the vision of the METIS project. IEEE Commun Mag 52(5), 26–35 (2014)D Gomez-Barquero, D Calabuig, JF Monserrat, N Garcia and J Perez-Romero, Hopfield neural network - based approach for joint dynamic resource allocation in heterogeneous wireless networks, in Proceedings 64th IEEE Vehicular Technology Conference (VTC), Montreal. 2006JF Monserrat, P Sroka, G Auer, J Cabrejas, D Martin-Sacristan, A Mihovska, R Rossi, A. Saul, R. Schoenen, Advanced Radio Resource Management for IMT-Advanced in WINNER+ (II), in Proc. Future Network and Mobile Summit, pp.1-9, June 2010.F Boccardi, RW Heath, A Lozano, TL Marzetta, P Popovski, Five disruptive technology directions for 5G. IEEE Commun Mag 52(2), 74–80 (2014)JG Andrews, S Buzzi, C Wan, SV Hanly, A Lozano, ACK Soong, JC Zhang, What will 5G be? IEEE J Sel Area Comm 32(6), 1065–1082 (2014)MN Tehrani, M Uysal, H Yanikomeroglu, Device-to-device communication in 5G cellular networks: challenges, solutions, and future directions. IEEE Commun Mag 52(5), 86–92 (2014)N Bhushan, L Junyi, D Malladi, R Gilmore, D Brenner, A Damnjanovic, R Sukhavasi, C Patel, S Geirhofer, Network densification: the dominant theme for wireless evolution into 5G. IEEE Commun Mag 52(2), 82–89 (2014)K Okino, T Nakayama, C Yamazaki, H Sato, Y Kusano, Pico Cell Range Expansion with Interference Mitigation toward LTE-Advanced Heterogeneous Networks, in Proc. of IEEE International Conference on Communications (ICC), 2011.P Mugen, L Dong, W Yao, L Jian Li, C Hsiao-Hwa, Self-configuration and self-optimization in LTE-advanced heterogeneous networks. IEEE Commun Mag 51(5), 36–45 (2013)I Siomina, D Yuan, Load Balancing in Heterogeneous LTE: Range Optimization via Offset and Load-coupling Characterization, in Proc. of IEEE Int. Conference on Communications (ICC). June 2012.KI Pedersen, Y Wang, B Soret, F Frederiksen, eICIC Functionality and Performance for LTE HetNet Co-Channel Deployments, in Proc. of IEEE Vehicular Technology Conf, Sep 2012X Gu, X Deng, Q Li, L Zhang, W Li, Capacity Analysis and Optimization in Heterogeneous Network with Adaptive Cell Range Control, Int. J. Antennas. Propag. 2014(215803), 10 (2014)K Smiljkovikj, P Popovski, L Gavrilovska, Analysis of the Decoupled Access for DL and UL in Wireless Heterogeneous Networks, in IEEE Wireless Communications Letters, in press, doi:10.1109/LWC.2015.2388676.P Agyapong, M. Iwamura, D. Staehle, W. Kiess, A. Benjebbour, Design considerations for a 5G network architecture. IEEE Commun Mag 52(11), 65–75 (2014)L Yan, X Fang, Reliability Evaluation of 5G C/U-plane Decoupled Architecture for High-speed Railway. EURASIP J Wirel Commun Netw 2014, 127 (2014)B Zafar, S Gherekhloo, M Haardt, Analysis of multihop relaying networks: communication between range-limited and cooperative nodes. IEEE Veh Technol Mag 7(3), 40–47 (2012)Study on Mobile Relay for Evolved Universal Terrestrial Radio Access (E-UTRA), 3GPP TR 36.836, V2.0.2, July 2013.A Krendzel, LTE-A Mobile Relay Handling: Architecture Aspects, in Proc. of the 19th European Wireless Conference (EW), Guildford, UK, pp. 1–6, 2013.M Khanfouci, Y Sui, A Papadogiannis, and M FĂ€rber, Moving Relays and Mobility aspects, ARTIST4G project deliverable D3.5c-v2.0, 2012.F Haider, M Dianati, and R Tafazolli, A Simulation Based Study of Mobile Femtocell Assisted LTE Networks, in Proc. Of the 7th International Wireless Communications and Mobile Computing Conference (IWCMC), Istanbul, Turkey, pp. 2198–2203, 2011F Haider, W Haiming, H Haas, Y Dongfeng, W Haiming, G Xiqi, Y Xiao-Hu, E Hepsaydir, Spectral efficiency enalysis of mobile Femtocell based cellular systems, in Proc. of the 13th International Conference on Communication Technology (ICCT), Jinan, pp. 347–351, September 2011.ICT-317669 METIS project, Initial report on horizontal topics, first results and 5G system concept, Deliverable D6.2, April 2014, https://www.metis2020.com/documents/deliverables/Study on LTE Device to Device Proximity Services, 3GPP TR 36.843, 2014.V Yazıcı, UC Kozat, M Oguz, Sunay, A new control plane for 5G network architecture with a case study on unified handoff, mobility, and routing management. IEEE Commun Mag 52(11), 76–85 (2014)F Malandrino, C Casetti, C-F Chiasserini, Toward D2D-enhanced heterogeneous networks. IEEE Commun Mag 52(11), 94–100 (2014)A Asadi, Q Wang, V Mancuso, A survey on device-to-Device communication in cellular networks. IEEE Commun Surv Tutor 16(4), 1801–1819 (2014)D Feng, L Lu, YY Wu, GY Li, G Feng, S Li, Device-to-device communications underlaying cellular networks. IEEE Trans Commun 61(8), 3541–3551 (2013)C Xu, L Song, Z Han, Q Zhao, X Wang, X Cheng, B Jiao, Efficiency resource allocation for device-to-device underlay communication systems: a reverse iterative combinatorial auction based approach. IEEE J Sel Area Comm 31(9), 348–358 (2013)S Lingyang, D Niyato, H Zhu, E Hossain, Game-theoretic resource allocation methods for device-to-device communication. IEEE Wireless Commun 21(3), 136–144 (2014)G Aloi, M Di Felice, V LoscrĂŹ, P Pace, G Ruggeri, Spontaneous smartphone networks as a user-centric solution for the future internet. IEEE Commun Mag 52(12), 26–33 (2014)PA Frangoudis, GC Polyzos, Security and performance challenges for user-centric wireless networking. IEEE Commun Mag 52(12), 48–55 (2014)ITU-R M.2079, in Technical and operational information for identifying Spectrum for the terrestrial component of future development of IMT-2000 and IMT-Advanced, 2006AB MacKenzie, LA DaSilva, Application of signal processing to addressing wireless data demand [in the spotlight]. IEEE Signal Process Mag 29(6), 168–166 (2012)X Cheng, Y Koucheryavy, Y Li, F Zhao, T Znati (ed.), Dynamic Spectrum Access for Throughput, Delay, and Fairness Enhancement In Cognitive Radio Networks, EURASIP J Wirel Commun Netw, November 2014MR Akdeniz, Y Liu, MK Samimi, S Sun, S Rangan, TS Rappaport, E Erkip, Millimeter wave channel modeling and cellular capacity evaluation. IEEE J Sel Area Comm 32(6), 1164–1179 (2014)A Adhikary, E Al Safadi, M Samimi, R Wang, G Caire, TS Rappaport, AF Molisch, Joint spatial division and multiplexing for mm-wave channels. IEEE J Sel Area Comm 32(6), 1239–1255 (2014)K Pentikousis, Y Wang, W Hu, Mobileflow: toward software-defined mobile networks. IEEE Commun Mag 51(7), 44–53 (2013)E3 D2.4. Cognitive Function mapping to Networks Architectures, Standard Engineering and Software Technologies for Cognitive Radios, E3 Project Deliverable 2.4, December 2009.R Wang, H Hu, X Yang, Potentials and challenges of C-RAN supporting Multi-RATs toward 5G mobile networks. IEEE. Access. 2(1187), 1195 (2014)V Jungnickel, K Manolakis, W Zirwas, B Panzner, V Braun, M Lossow, M Sternad, R Apelfrojd, T Svensson, The role of small cells, coordinated multipoint, and massive MIMO in 5G. IEEE Commun Mag 52(5), 44–51 (2014)E Larsson, O Edfors, F Tufvesson, T Marzetta, Massive MIMO for next generation wireless systems. IEEE Commun Mag 52(2), 186–195 (2014)W Roh, S Ji-Yun, P Jeongho, L Byunghwan, L Jaekon, K Yungsoo, C Jaeweon, C Kyungwhoon, F Aryanfar, Millimeter-wave Beamforming as an Enabling Technology for 5G Cellular Communications: Theoretical Feasibility and Prototype Results. IEEE Commun Mag 2(2), 106–113 (2014)AL Swindlehust, E Ayanoglu, P Heydari, F Capolino, Millimeter-wave massive MIMO: the next wireless revolution? IEEE Commun Mag 52(9), 56–62 (2014)L Lu, GY Li, AL Swindlehurst, A Ashikhmin, Z Rui, An overview of massive MIMO: benefits and challenges. IEEE J Sel Top Signal Process 8(5), 742–758 (2014)S Roger, D Calabuig, J Cabrejas, JF Monserrat, Multi-user non-coherent detection for downlink MIMO communication. IEEE Signal Process Lett 21(10), 1225–1229 (2014)X Wang, M Chen, T Taleb, A Ksentini, V Leung, Cache in the air: exploiting content caching and delivery techniques for 5G systems. IEEE Commun Mag 52(2), 131–139 (2014)ETSI ISG NFV (Operator Group), Network Functions Virtualisation – Network Operator Perspectives on Industry Progress, Updated White Paper, October 2013NGMN Alliance, in Suggestions on potential solutions for C-RAN, White Paper, January 2013ETSI ISG NFV, Network Functions Virtualisation (NFV); Virtual Network Functions Architecture, v1.1.1, Dec 2014.A Tzanakaki, MP Anastasopoulos, GS Zervas, BR Rofoee, R Nejabati, D Simeonidou, Virtualization of heterogeneous wireless-optical network and IT infrastructures in support of cloud and mobile cloud services. IEEE Commun Mag 51(8), 155–161 (2013)A Manzalini, R Saracco, C Buyukkoc, P Chemuouil, S KukliƄski, A Gladisch, M Fukui, W Shen, M Fujiwara, K Shimano, E Dekel, D Soldani, M Ulema, W Cerroni, F Callegati, G Schembra, V Riccobene, C Mas Machuca, A Galis, J Mueller, Software-Defined Networks for Future Networks and Services: Main Technical Challenges and Business Implications, IEEE Workshop SDN4FNS, 1–16, 2013CEPT ECC, in Licensed Shared Access (LSA), ECC Report 205, February 2014IEEE 802.11, in IEEE 802.11-2012 Part11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications, IEEE Standard, March 2012D MartĂ­n-SacristĂĄn, JF Monserrat, J Cabrejas-Peñuelas, D Calabuig, S Garrigas, N Cardona, On the way towards fourth-generation mobile: 3GPP LTE and LTE-Advanced. EURASIP J Wirel Commun Netw 2009, 10 (2009)ICT-317669 METIS, Final report on architecture, Deliverable D6.4, January 2015, https://www.metis2020.com/documents/deliverables/ICT-317669 METIS, Report on simulation results and evaluations, Deliverable D6.5, February 2015, https://www.metis2020.com/documents/deliverables/Ö Bulakci, Z Ren, C Zhou, J Eichinger, P Fertl, S Stanczak, Dynamic Nomadic Node Selection for Performance Enhancement in Composite Fading/Shadowing Environments, (IEEE VTC 2014-Spring, Seoul, South Korea)ICT-317669 METIS, Final report on network-level solutions, Deliverable D4.3 Version 1, February 201
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