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Sample records for networks xin yao

  1. Characteristics of nitrogen retention along the river network of upper Xin'anjiang catchment in China

    Science.gov (United States)

    Wang, A.; Yang, D.; Tang, L.

    2014-12-01

    Nitrogen (N) originates mainly from the non-point source (NPS) in the headwaters of many rivers. Understanding the nitrogen retention characteristics along the river network is important for land management in order to implement water resources protection. This study employs a geomorphology based non-point source pollution (GBNP) model to simulate the hillslope hydrological processes, sediment and pollutants transportation in the upper Xin'anjiang catchment in recent 10 years from 2001 to 2010. Calibration and validation of the GBNP model are carried out carefully using the observed discharge, sediment and total nitrogen (TN) concentrations at several hydrological gauges, and then the simulated results of the whole catchment are used to analyze the spatial and temporal distribution of nitrogen along the river networks with emphasis on its retention characteristics. The simulated results indicate that annual TN loaded from the hillslopes in the study catchment ranges from nearly 4000 ton to 11,000 ton and relatively higher TN load occurred in spring and summer. Average TN loads from hillslopes have significant positive correlation with the irrigated-cropland area (correlation coefficient =0.820), and significant negative correlation with the area of forest and grassland (correlation coefficient =-0.427 and -0.246). Seasonal nitrogen retention ratio in the river networks of study catchment in last 10 years varies from 0%-81%, and the streams of order 1 in the Horton-Strahler ordering system has the highest retention ratio and is followed by order 2, order 3 and order 4. The results also indicate that nitrogen retention ratio has positive correlation with river length and negative correlation with discharge and velocity. Scenario analysis of fertilizer application demonstrates that the nitrogen retention ratio increases logarithmically with the TN load and reach a maximum value rapidly.

  2. On Yao's method of translation

    NARCIS (Netherlands)

    Liu, X; Hoede, C.

    2002-01-01

    Machine Translation, i.e., translating one kind of natural language to another kind of natural language by using a computer system, is a very important research branch in Artificial Intelligence. Yao developed a method of translation that he called ``Lexical-Semantic Driven". In his system he

  3. KOUADIO YAO P..pmd

    African Journals Online (AJOL)

    Administrateur

    1Laboratoire de Botanique U.F.R. Biosciences, Université de Cocody-Abidjan, 22 B.P. 582 Abidjan 22 Côte d'Ivoire. E-mail : k_yao_pros@yahoo. 2Laboratoire de Physiologie ... également conduites sur ces deux parcelles, en vue de suivre la dynamique des adventices au cours du cycle cultural des bananiers. Il ressort de ...

  4. 2168-IJBCS-Article-Yao Brou

    African Journals Online (AJOL)

    hp

    Original Paper http://indexmedicus.afro.who.int. Contamination des basidiomycètes (Volvariella volvacea et Termitomyces spp) des marchés abidjanais par le plomb, le cadmium, le mercure et le zinc. Gains Kouakou KPAN KPAN1*, Lazare Brou YAO2, Ardjouma DEMBELE2,. Sory Karim TRAORE3 et Francis MESSOUM4.

  5. 2367-IJBCS-Article-Koffi Mathias Yao

    African Journals Online (AJOL)

    hp

    10.4314/ijbcs.v9i3.6. Original Paper http://indexmedicus.afro.who.int. Evaluation des consommations excessives d'alcool (binge drinking) en Côte d'Ivoire : cas de la ville d'Abidjan. Koffi Mathias YAO*, Pierrette Célestine BADJO, Bessekon Denis ...

  6. New and improved spanning ratios for Yao graphs

    DEFF Research Database (Denmark)

    Barba, Luis; Bose, Prosenjit; Damian, Mirela

    2014-01-01

    For a set of points in the plane and a fixed integer κ > 0, the Yao graph Yκ partitions the space around each point into κ equiangular cones of angle θ = 2π/κ, and connects each point to a nearest neighbor in each cone. It is known for all Yao graphs, with the sole exception of Y5, whether or not...

  7. Emergence of Xin demarcates a key innovation in heart evolution.

    Directory of Open Access Journals (Sweden)

    Shaun E Grosskurth

    2008-08-01

    Full Text Available The mouse Xin repeat-containing proteins (mXinalpha and mXinbeta localize to the intercalated disc in the heart. mXinalpha is able to bundle actin filaments and to interact with beta-catenin, suggesting a role in linking the actin cytoskeleton to N-cadherin/beta-catenin adhesion. mXinalpha-null mouse hearts display progressively ultrastructural alterations at the intercalated discs, and develop cardiac hypertrophy and cardiomyopathy with conduction defects. The up-regulation of mXinbeta in mXinalpha-deficient mice suggests a partial compensation for the loss of mXinalpha. To elucidate the evolutionary relationship between these proteins and to identify the origin of Xin, a phylogenetic analysis was done with 40 vertebrate Xins. Our results show that the ancestral Xin originated prior to the emergence of lamprey and subsequently underwent gene duplication early in the vertebrate lineage. A subsequent teleost-specific genome duplication resulted in most teleosts encoding at least three genes. All Xins contain a highly conserved beta-catenin-binding domain within the Xin repeat region. Similar to mouse Xins, chicken, frog and zebrafish Xins also co-localized with beta-catenin to structures that appear to be the intercalated disc. A putative DNA-binding domain in the N-terminus of all Xins is strongly conserved, whereas the previously characterized Mena/VASP-binding domain is a derived trait found only in Xinalphas from placental mammals. In the C-terminus, Xinalphas and Xinbetas are more divergent relative to each other but each isoform from mammals shows a high degree of within-isoform sequence identity. This suggests different but conserved functions for mammalian Xinalpha and Xinbeta. Interestingly, the origin of Xin ca. 550 million years ago coincides with the genesis of heart chambers with complete endothelial and myocardial layers. We postulate that the emergence of the Xin paralogs and their functional differentiation may have played a key

  8. Cardioprotective roles of the Chinese medicinal formula Bao-Xin ...

    African Journals Online (AJOL)

    Background: Bao-Xin-Tang (BXT) is a traditional Chinese medicinal formula used for the treatment of coronary heart disease and known to have favorable therapeutic benefits. The current study was designed to determine whether BXT has a cardioprotective role for acute myocardial infarction. The underlying mechanisms ...

  9. New Insights into the Roles of Xin Repeat-Containing Proteins in Cardiac Development, Function, and Disease

    Science.gov (United States)

    Wang, Qinchuan; Lin, Jenny Li-Chun; Erives, Albert J.; Lin, Cheng-I; Lin, Jim Jung-Ching

    2016-01-01

    Since the discovery of Xin repeat-containing proteins in 1996, the importance of Xin proteins in muscle development, function, regeneration, and disease has been continuously implicated. Most Xin proteins are localized to myotendinous junctions of the skeletal muscle and also to intercalated discs (ICDs) of the heart. The Xin gene is only found in vertebrates, which are characterized by a true chambered heart. This suggests that the evolutionary origin of the Xin gene may have played a key role in vertebrate origins. Diverse vertebrates including mammals possess two paralogous genes, Xinα (or Xirp1) and Xinβ (or Xirp2), and this review focuses on the role of their encoded proteins in cardiac muscles. Complete loss of mouse Xinβ (mXinβ) results in the failure of forming ICD, severe growth retardation, and early postnatal lethality. Deletion of mouse Xinα (mXinα) leads to late-onset cardiomyopathy with conduction defects. Molecular studies have identified three classes of mXinα-interacting proteins: catenins, actin regulators/modulators, and ion-channel subunits. Thus, mXinα acts as a scaffolding protein modulating the N-cadherin-mediated adhesion and ion-channel surface expression. Xin expression is significantly upregulated in early stages of stressed hearts, whereas Xin expression is downregulated in failing hearts from various human cardiomyopathies. Thus, mutations in these Xin loci may lead to diverse cardiomyopathies and heart failure. PMID:24725425

  10. Xin-deficient mice display myopathy, impaired contractility, attenuated muscle repair and altered satellite cell functionality.

    Science.gov (United States)

    Al-Sajee, D; Nissar, A A; Coleman, S K; Rebalka, I A; Chiang, A; Wathra, R; van der Ven, P F M; Orfanos, Z; Hawke, T J

    2015-06-01

    Xin is an F-actin-binding protein expressed during development of cardiac and skeletal muscle. We used Xin-/- mice to determine the impact of Xin deficiency on different aspects of skeletal muscle health, including functionality and regeneration. Xin-/- skeletal muscles and their satellite cell (SC) population were investigated for the presence of myopathic changes by a series of histological and immunofluorescent stains on resting uninjured muscles. To further understand the effect of Xin loss on muscle health and its SCs, we studied SCs responses following cardiotoxin-induced muscle injury. Functional data were determined using in situ muscle stimulation protocol. Compared to age-matched wild-type (WT), Xin-/- muscles exhibited generalized myopathy and increased fatigability with a significantly decreased force recovery post-fatiguing contractions. Muscle regeneration was attenuated in Xin-/- mice. This impaired regeneration prompted an investigation into SC content and functionality. Although SC content was not different, significantly more activated SCs were present in Xin-/- vs. WT muscles. Primary Xin-/- myoblasts displayed significant reductions (approx. 50%) in proliferative capacity vs. WT; a finding corroborated by significantly decreased MyoD-positive nuclei in 3 days post-injury Xin-/- muscle vs. WT. As more activated SCs did not translate to more proliferating myoblasts, we investigated whether Xin-/- SCs displayed an exaggerated loss by apoptosis. More apoptotic SCs (TUNEL+/Pax7+) were present in Xin-/- muscle vs. WT. Furthermore, more Xin-/- myoblasts were expressing nuclear caspase-3 compared to WT at 3 days post-injury. Xin deficiency leads to a myopathic condition characterized by increased muscle fatigability, impaired regeneration and SC dysfunction. © 2015 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  11. Mao Was My Neighbour: Yao Zhongda and the "Opening" of Chinese Adult Education

    Science.gov (United States)

    Boshier, Roger

    2013-01-01

    After Deng Xiaoping's 1978 reform and opening, foreigners had a chance to see adult education in China. As a result, many met Yao Zhongda, Chief of the Bureau of Workers' and Peasants Education. From 1921 onwards, adult education has been a vital corollary of Communist revolution. Although Yao's biography was extremely relevant to what foreigners…

  12. [The cultural and medical significance of Xin an mingzuzhi(History of Famous Family in Xin'an)].

    Science.gov (United States)

    Hu, A H; Wan, S M

    2016-01-28

    History of Famous Family in Xin'an includes abundant information and important value of the medical cultural history, including the medical family, medical ethics and the number of the famous doctors and its distribution, the medical books and its outline the medical ethics, the diseases. As for the 115 famous doctors recorded in this book, Shexian county owns the most while Jixi county owns the least, and of the average number of famous doctors among the 10, 000 local people, Yixian county owns the most while Xiuning county owns the least. History of Famous Family in Xin'an includes 26 medical books, ranging from medical literature study, gynecological treatment, external medical treatment, diagnosis and treatment of pediatric diseases, ancient medical case records, medical education, acu-moxibustion and summary of other medical experiences. The book also demonstrates the noble morality of doctors, development of doctor' family, and records of paralytic stroke, epistaxis, tuberculous consumptive diseases, furunculosis, dystocia and some infectious diseases.

  13. Cardioprotective effects of Dan-Yang-Fu-Xin decoction on chronic ...

    African Journals Online (AJOL)

    Cardioprotective effects of Dan-Yang-Fu-Xin decoction on chronic heart failure in rats. ... including fractional shortening (FS), ejection fraction (EF), heart rate (HR) ... in body weight and increase in cardiac weight (p < 0.05) induced by CHF.

  14. [Dialectic research on family lineage of Wu Kun, a Xin'an famous physician].

    Science.gov (United States)

    Zhang, L; Yao, S

    2000-07-01

    The records on the family lineage of a personage in the medical circle should be as accurate as possible. In Textual Research on Xin'an Famous Doctor, it is said that the Xin'an famous physician Wu Kun was the grandson of Wu Znenglun. Through dialectic research, this saying was proved to be untrue. Wu Kun's grandfather is Wu Yuan - chang, who had no direct blood relationship with Wu Zhenglun.

  15. YAO is a nucleolar WD40-repeat protein critical for embryogenesis and gametogenesis in Arabidopsis.

    Science.gov (United States)

    Li, Hong-Ju; Liu, Nai-You; Shi, Dong-Qiao; Liu, Jie; Yang, Wei-Cai

    2010-08-11

    In flowering plants, gametogenesis generates multicellular male and female gametophytes. In the model system Arabidopsis, the male gametophyte or pollen grain contains two sperm cells and a vegetative cell. The female gametophyte or embryo sac contains seven cells, namely one egg, two synergids, one central cell and three antipodal cells. Double fertilization of the central cell and egg produces respectively a triploid endosperm and a diploid zygote that develops further into an embryo. The genetic control of the early embryo patterning, especially the initiation of the first zygotic division and the positioning of the cell plate, is largely unknown. Here we report the characterization of a mutation, yaozhe (yao), that causes zygote arrest and misplacement of cell plate of the zygote, leading to early embryo lethality. In addition, gametophyte development is partially impaired. A small portion of the mutant embryo sacs are arrested at four-nucleate stage with aberrant nuclear positioning. Furthermore, the competence of male gametophytes is also compromised. YAO encodes a nucleolar protein with seven WD-repeats. Its homologues in human and yeast have been shown to be components of the U3 snoRNP complex and function in 18S rRNA processing. YAO is expressed ubiquitously, with high level of expression in tissues under active cell divisions, including embryo sacs, pollen, embryos, endosperms and root tips. Phenotypic analysis indicated that YAO is required for the correct positioning of the first zygotic division plane and plays a critical role in gametogenesis in Arabidopsis. Since YAO is a nucleolar protein and its counterparts in yeast and human are components of the U3 snoRNP complex, we therefore postulate that YAO is most likely involved in rRNA processing in plants as well.

  16. Based on Gaussian Mixture Model to Explore the General Characteristic and Make Recognition of XinTianYou

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    Li Juan

    2016-01-01

    Full Text Available XinTianYou, a folk song style from Shannxi province in China, is considered to be a precious traditional culture heritage. Research about XinTianYou is important to the overall Chinese folk music theory and is potentially quite useful for the culture preservation and applications. In this paper, we analyze the general characteristics of XinTianYou by using the pitch, rhythm features and the combination of these two features. First, we use the Gaussian Mixture Model (GMM to cluster the XinTianYou audio based on pitch and rhythm respectively, and analyze the general characteristics of XinTianYou based on the clustering result. Second, we propose an improved Features Relative Contribution Algorithm (CFRCA to com-pare the contributions of pitch and rhythm. Third, the probability of a song being XinTianYou can be estimated based on the GMM and the cosine similarity distance. The experimental results show that XinTianYou has large pitch span and large proportion of high pitch value (about 22%. Regarding the rhythm, we find that moderato is dominated while lento-moderato keep a similar ratio as moderato-allegro. The similarity between pitch features of all XinTianYou songs is more significant than rhythm features. Additionally, the average accuracy of XinTianYou recognition reaches 92.4% based on our method

  17. Cardioprotective effects of Dan-Yang-Fu-Xin decoction on chronic ...

    African Journals Online (AJOL)

    Purpose: To evaluate the cardioprotective effects and possible mechanisms of Dan-Yang-Fu-Xin decoction (DYFX) in a rat chronic heart failure (CHF). Methods: A CHF rat model induced by ligation of the left anterior descending coronary artery was used to investigate the cardioprotective effects of DYFX. After intragastric ...

  18. Comment on P. Xin et al./ Advances in Water Resources 91 1-10

    NARCIS (Netherlands)

    Zaadnoordijk, W.J.

    2016-01-01

    Xin et al. (2016) present an approximate analytical solution to a variable saturated formulation of a drainage problem. They compared their solution to a saturated flow-based model and found a large discrepancy. However, the discrepancy is due to the value of the storage coefficient used and not to

  19. cardioprotective roles of the chinese medicinal formula bao-xin-tang ...

    African Journals Online (AJOL)

    Background: Bao-Xin-Tang (BXT) is a traditional Chinese medicinal formula used for the treatment of coronary heart disease and known to have favorable therapeutic benefits. The current study was designed to determine whether BXT has a cardioprotective role for acute myocardial infarction. The underlying mechanisms ...

  20. Traditional Chinese Medicine Shuang Shen Ning Xin Attenuates Myocardial Ischemia/Reperfusion Injury by Preserving of Mitochondrial Function

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    Xueli Li

    2014-01-01

    Full Text Available To investigate the potential cardioprotective effects of Shuang Shen Ning Xin on myocardial ischemia/reperfusion injury. Wistar rats were treated with trimetazidine (10 mg/kg/day, ig, Shuang Shen Ning Xin (22.5, 45 mg/kg/day, ig, or saline for 5 consecutive days. Myocardial ischemia/reperfusion injury was induced by ligation of the left anterior descending coronary artery for 40 min and reperfusion for 120 min on the last day of administration. It is found that Shuang Shen Ning Xin pretreatment markedly decreased infarct size and serum LDH levels, and this observed protection was associated with reduced myocardial oxidative stress and cardiomyocyte apoptosis after myocardial ischemia/reperfusion injury. In addition, further studies on mitochondrial function showed that rats treated with Shuang Shen Ning Xin displayed decreased mitochondrial swelling and cytosolic cytochrome c levels, which were accompanied by a preservation of complex I activities and inhibition of mitochondrial permeability transition. In conclusion, the mitochondrial protective effect of Shuang Shen Ning Xin could be a new mechanism, by which Shuang Shen Ning Xin attenuates myocardial ischemia/reperfusion injury.

  1. [Diversity of ectomycorrhizal fungi associated with Picea asperata in Xin Jiashan Forest of Qinling Mountains].

    Science.gov (United States)

    Geng, Rong; Geng, Zengchao; Huang, Jian; He, Wenxiang; Hou, Lin; She, Diao; Zhao, Jun; Shang, Jie

    2015-07-04

    To study the diversity of ectomycorrhizal fungi associated with Picea asperata in Xin Jiashan Forest of Qinling Mountains. This method combined the field investigation, morphological and molecular biology to identify ectomycorrhizal fungi. There were 37 different ectomycorrhizal fungi under 14 genera of 10 families on spruce in Xin Jiashan Forest of Qinling Mountains, 34 types belonged to Basidiomycetes, 1 to Ascomycete and 2 to unknown species. Among these identified ectomycorrhizal fungi types, Inocybe sp. was the dominant group; Russula nauseosa was the most dominant species; Hygrophorus sp., Tomentella coerulea, Inocybe sp. 1, Helotiaceae sp. and Lactarius deterrimus were common species; and the rest species were rare species. The large number but relatively rare species of dominant family and the small number but relatively more species of rare family survived in ectomycorrhizal fungal communities of Picea asperata. For the extreme degradation in arid area of western ecological system, identifing some rare family for further development and utilization had very important practical significance.

  2. Description of immature stages of Scymnus (Neopullus) sinuanodulus Yu and Yao (Coleoptera: Coccinellidae) with notes on life history

    Science.gov (United States)

    Wenhua Lu; Phetsamon Souphanya; Michael E. Montgomery

    2002-01-01

    We describe for the first time immature stages of the Scymnus subgenus Neopullus; namely the egg, larval (4 instars), and pupal stages of Scymnus (Neopullus) sinuanodulus Yu and Yao (Coleoptera: Coccinellidae), which is indigenous to China. This lady beetle was imported to...

  3. Bacterial diversity analysis of Zhenjiang Yao meat during refrigerated and vacuum-packed storage by 454 pyrosequencing.

    Science.gov (United States)

    Xiao, Xiang; Dong, Ying; Zhu, Ying; Cui, Henglin

    2013-04-01

    Zhenjiang Yao meat is a traditional variety of cooked marinated and jellied pork food in China. It is usually stored refrigerated to prevent gelatine liquefaction. Our understanding of the bacterial populations found in Zhenjiang Yao meat is limited. This study was designed to explore both the bacterial diversity and the main bacterial flora of Zhenjiang Yao meat using pyrosequencing of tagged amplicons from the V3 and V9 regions of the 16S rRNA gene. A total of 53,363 bacterial sequences from five samples and an average 10,672 reads of each sample were acquired and used in the analysis of microbial diversity. The bacterial diversity was observed to increase weekly, and the main bacterial flora changed significantly under refrigerated vacuum-packaged storage. The predominant bacteria were Vibrio during the first 7 days of storage, whereas Shewanella, Lactobacillus, Lactococcus, Yersinia, and other Enterobacteriaceae members were the main groups after 15 days in refrigerated storage. The bacterial population changed significantly after 15 days, and the bacterial communities in the 30 days sample were significantly different from all other samples. In comparison with culture-dependant method, pyrosequencing provides a more comprehensive estimate of bacterial diversity and more close to the real bacterial composition in Zhenjiang Yao meat.

  4. [Collation and research on the different texts in Qian jin yao fang (Precious essential formulary, PEF)].

    Science.gov (United States)

    Lin, Nan; Wang, Lizi

    2002-04-01

    There is considerable difference in the texts between PEF and the archaic editions Sun zhen ren qian jin fang (The Immortal Sun's Precious Formulary, ISPF) and the Song - revised edition Bei ji qian jin yao fang (Precious Essential Formulary for Emergency, PEFE). It is hoped that the real features of PEF can be worked out through collated studies on these two editions so as to offer a basis for systematic research on PEF. At the same time, it has been proved that during the revision and collation of PEF by the Song scholars, it is certain that dramatic revisions had been made on its medical materials, especially an abundant amount of medical materials were added. As a result, the current circulated edition of PEFE does have obvious differences with Sun's original work, while ISPF, in contrast, preserves the original features of Sun Simiao. Hence, ISPF is of important academic significance in the in - depth study of PEF.

  5. Polymorphism of rs1044925 in the acyl-CoA:cholesterol acyltransferase-1 gene and serum lipid levels in the Guangxi Bai Ku Yao and Han populations

    Directory of Open Access Journals (Sweden)

    Yan Ting-Ting

    2010-12-01

    Full Text Available Abstract Background The association of rs1044925 polymorphism in the acyl-CoA:cholesterol acyltransferase-1 (ACAT-1 gene and serum lipid profiles is not well known in different ethnic groups. Bai Ku Yao is a special subgroup of the Yao minority in China. The present study was carried out to clarify the association of rs1044925 polymorphism in the ACAT-1 gene and several environmental factors with serum lipid levels in the Guangxi Bai Ku Yao and Han populations. Methods A total of 626 subjects of Bai Ku Yao and 624 participants of Han Chinese were randomly selected from our previous stratified randomized cluster samples. Genotyping of rs1044925 polymorphism in the ACAT-1 gene was performed by polymerase chain reaction and restriction fragment length polymorphism combined with gel electrophoresis, and then confirmed by direct sequencing. Results The levels of serum total cholesterol (TC, high-density lipoprotein cholesterol (HDL-C, apolipoprotein (Apo AI and ApoB were lower in Bai Ku Yao than in Han (P P P P P P Conclusions These results suggest that the polymorphism of rs1044925 in the ACAT-1 gene is mainly associated with female serum TC, LDL-C and ApoB levels in the Bai Ku Yao population. The C allele carriers had lower serum TC, LDL-C and ApoB levels than the C allele noncarriers.

  6. Hydrological daily rainfall-runoff simulation with BTOPMC model and comparison with Xin'anjiang model

    Directory of Open Access Journals (Sweden)

    Hong-jun Bao

    2010-06-01

    Full Text Available A grid-based distributed hydrological model, the Block-wise use of TOPMODEL (BTOPMC, which was developed from the original TOPMODEL, was used for hydrological daily rainfall-runoff simulation. In the BTOPMC model, the runoff is explicitly calculated on a cell-by-cell basis, and the Muskingum-Cunge flow concentration method is used. In order to test the model's applicability, the BTOPMC model and the Xin'anjiang model were applied to the simulation of a humid watershed and a semi-humid to semi-arid watershed in China. The model parameters were optimized with the Shuffle Complex Evolution (SCE-UA method. Results show that both models can effectively simulate the daily hydrograph in humid watersheds, but that the BTOPMC model performs poorly in semi-humid to semi-arid watersheds. The excess-infiltration mechanism should be incorporated into the BTOPMC model to broaden the model's applicability.

  7. Topological phase transition in layered XIn2P2 (X = Ca, Sr)

    Science.gov (United States)

    Wang, Zhenwei; Wang, Guangtao; Shi, Xianbiao; Wang, Dongyang; Tian, Xin

    2017-11-01

    Based on fully relativistic first-principles calculations, we studied the topological properties of layered XIn2P2 (X = Ca, Sr). Band inversion can be induced by strain without SOC, forming one nodal ring in the kz = 0 plane, which is protected by the coexistence of time reversal and glide mirror symmetries. Including SOC, a substantial band gap is opened along the nodal line and the line-node semimetal would evolve into a topological insulator. These results reveal a category of materials showing quantum phase transition from trivial semiconductors and topologically nontrivial insulators by tuneable elastic strain engineering. Our investigations provide a new perspective about the formation of topological line-node semimetal under stain.

  8. Association of MYLIP rs3757354 SNP and several environmental factors with serum lipid levels in the Guangxi Bai Ku Yao and Han populations

    Directory of Open Access Journals (Sweden)

    Yan Ting-Ting

    2012-10-01

    Full Text Available Abstract Background The association of rs3757354 single nucleotide polymorphism (SNP in the E3 ubiquitin ligase myosin regulatory light chain-interacting protein (MYLIP, also known as IDOL gene and serum lipid levels is not well known in the general population. The present study aimed to detect the association of rs3757354 SNP and several environmental factors with serum lipid levels in the Guangxi Bai Ku Yao and Han populations. Method A total of 627 subjects of Bai Ku Yao minority and 614 participants of Han nationality were randomly selected from our stratified randomized cluster samples. Genotyping of the rs3757354 SNP was performed by polymerase chain reaction and restriction fragment length polymorphism combined with gel electrophoresis, and then confirmed by direct sequencing. Results The levels of serum total cholesterol (TC, high-density lipoprotein cholesterol (HDL-C, low-density lipoprotein cholesterol (LDL-C, apolipoprotein (Apo AI and ApoB were lower in Bai Ku Yao than in Han (P P P 0.05; respectively. There were no significant differences in the genotypic and allelic frequencies between males and females in both ethnic groups. The levels of HDL-C in Bai Ku Yao were different among the genotypes (P P P P Conclusions The present study suggests that the MYLIP rs3757354 SNP is associated with serum TC, HDL-C and ApoAI levels in the Bai Ku Yao and Han populations. But the association is different between the two ethnic groups.

  9. Sensing the quality parameters of Chinese traditional Yao-meat by using a colorimetric sensor combined with genetic algorithm partial least squares regression.

    Science.gov (United States)

    Huang, Xiaowei; Zou, Xiaobo; Zhao, Jiewen; Shi, Jiyong; Zhang, Xiaolei; Li, Zhihua; Shen, Lecheng

    2014-10-01

    Yao-meat is a traditional Chinese salted meat. Total volatile basic nitrogen content (TVB-N), total viable bacterial count (TVC), and residual nitrite (RN) level are important indexes of freshness for Yao-meat. This paper attempted the feasibility to determine TVB-N content, TVC and RN level in Yao-meat by a colorimetric sensor array chip. A color change profile for each sample was obtained by differentiating the image of sensor array before and after exposure to Yao-meat's volatile organic compounds. Genetic algorithm partial least squares regression (GA-PLS) was proposed to build the relationship between the TVB-N content, TVC, RN and the color change profiles of sensor array, and to select informative chemically responsive dyes for the three quality parameters. The GA-PLS models were achieved with RTVB-N=0.812, RTVC=0.856, RRN=0.855, in prediction set. This study demonstrated that colorimetric sensory array with GA-PLS algorithm could be used successfully to analyze the quality of Chinese traditional Yao-meat. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Neuroprotective mechanism of Kai Xin San: upregulation of hippocampal insulin-degrading enzyme protein expression and acceleration of amyloid-beta degradation

    Directory of Open Access Journals (Sweden)

    Na Wang

    2017-01-01

    Full Text Available Kai Xin San is a Chinese herbal formula composed of Radix Ginseng , Poria , Radix Polygalae and Acorus Tatarinowii Rhizome . It has been used in China for many years for treating amnesia. Kai Xin San ameliorates amyloid-β (Aβ-induced cognitive dysfunction and is neuroprotective in vivo , but its precise mechanism remains unclear. Expression of insulin-degrading enzyme (IDE, which degrades Aβ, is strongly correlated with cognitive function. Here, we injected rats with exogenous Aβ42 (200 μM, 5 μL into the hippocampus and subsequently administered Kai Xin San (0.54 or 1.08 g/kg/d intragastrically for 21 consecutive days. Hematoxylin-eosin and Nissl staining revealed that Kai Xin San protected neurons against Aβ-induced damage. Furthermore, enzyme-linked immunosorbent assay, western blot and polymerase chain reaction results showed that Kai Xin San decreased Aβ42 protein levels and increased expression of IDE protein, but not mRNA, in the hippocampus. Our findings reveal that Kai Xin San facilitates hippocampal Aβ degradation and increases IDE expression, which leads, at least in part, to the alleviation of hippocampal neuron injury in rats.

  11. Neuroprotective mechanism of Kai Xin San: upregulation of hippocampal insulin-degrading enzyme protein expression and acceleration of amyloid-beta degradation.

    Science.gov (United States)

    Wang, Na; Jia, Yong-Ming; Zhang, Bo; Xue, Di; Reeju, Maharjan; Li, Yan; Huang, Shu-Ming; Liu, Xue-Wei

    2017-04-01

    Kai Xin San is a Chinese herbal formula composed of Radix Ginseng, Poria, Radix Polygalae and Acorus Tatarinowii Rhizome. It has been used in China for many years for treating amnesia. Kai Xin San ameliorates amyloid-β (Aβ)-induced cognitive dysfunction and is neuroprotective in vivo, but its precise mechanism remains unclear. Expression of insulin-degrading enzyme (IDE), which degrades Aβ, is strongly correlated with cognitive function. Here, we injected rats with exogenous Aβ42 (200 μM, 5 μL) into the hippocampus and subsequently administered Kai Xin San (0.54 or 1.08 g/kg/d) intragastrically for 21 consecutive days. Hematoxylin-eosin and Nissl staining revealed that Kai Xin San protected neurons against Aβ-induced damage. Furthermore, enzyme-linked immunosorbent assay, western blot and polymerase chain reaction results showed that Kai Xin San decreased Aβ42 protein levels and increased expression of IDE protein, but not mRNA, in the hippocampus. Our findings reveal that Kai Xin San facilitates hippocampal Aβ degradation and increases IDE expression, which leads, at least in part, to the alleviation of hippocampal neuron injury in rats.

  12. [Remote sensing estimation of total suspended matter concentration in Xin'anjiang Reservoir using Landsat 8 data].

    Science.gov (United States)

    Zhang, Yi-bo; Zhang, Yun-lin; Zha, Yong; Shi, Kun; Zhou, Yong-qiang; Wang, Ming-zhu

    2015-01-01

    Total suspended matter (TSM) plays an important role in determining the underwater light climate, which then affects the lake primary production. Therefore, TSM concentration is an important parameter for lake water quality and water environment assessment. This study developed an empirical estimation model and presented the spatial distribution of TSM concentration for the relatively clear Xin'anjiang Reservoir based on the in situ ground data and the matching Landsat 8 data. The results showed that Band 2, Band 3 and Band 8 of Landsat 8 data were the sensitive bands of TSM estimation in Xin'anjiang Reservoir with the linear determination coefficients of 0.37, 0.51 and 0.42, respectively. However, the linear models using Band 2, Band 3 and Band 8 could not give a reasonable and satisfying estimation accuracy. Therefore, a three-band combination estimation model of TSM concentration using Band 2, Band 3 and Band. 8 was calibrated and validated to improve the TSM concentration estimation accuracy. The determination coefficient, mean relative error and root mean square error were 0.92, 11% and 0.16 mg x L(-1), respectively for the three-band combination model. Overall, the TSM concentration was relatively low in Xin'anjiang Reservoir, ranging from 0. 04 to 24. 54 mg x L(-1) with a mean value of 2.19 mg x L(-1). Higher TSM concentrations were distributed in the nearshore zones and small bays such as Fengshuling bay, Fenkou bay, Weiping bay, Anyang bay, Dashu bay and Linqi bay, which were affected by input rivers rainfall and human dredging activity. Therefore, this study demonstrated that the combination of three bands using Landsat 8 data could be used to estimate the TSM concentration in the relatively clear Xin'anjiang Reservoir.

  13. Processes affecting the spatial distribution of seagrass meadow sedimentary material on Yao Yai Island, Thailand

    Science.gov (United States)

    Quak, Michelle S. Y.; Ziegler, Alan D.; Benner, Shawn G.; Evans, Sam; Todd, Peter A.; Gillis, Lucy G.; Vongtanaboon, Sukanya; Jachowski, Nick; Bouma, Tjeerd J.

    2016-12-01

    Many islands throughout SE Asia are experiencing rapid development and land-cover conversion that potentially threaten sensitive coastal ecosystems, such as seagrasses, through increased loading of sediment and nutrients originating from disturbed catchments draining to the sea. To evaluate this threat for one such island in Southern Thailand (Yao Yai), we perform sediment source tracing via end-member mixing analysis using stable isotopes δ13C and δ15N in organic matter to explore sediment loading in a seagrass meadow. The analysis indicates that sedimentary material in the meadow originates mostly from ocean-associated sources (∼62% from seagrass detritus, seston, and ocean sediments). Terrestrial material comprises ∼19% of the organic material found in the seagrass meadow, with another 20% originating from an adjacent mangrove forest. Approximately one-fourth of the seagrass meadow material (24%) is detritus that has been (re)deposited internally. The high contribution of terrestrial-derived organic matter deposited near the river mouth demonstrates that substantial quantities of sediment are being transferred from upslope erosion sources into the seagrass meadow. However, only a small amount of this material is deposited throughout the entire bay because much of the terrestrial- and mangrove-derived sediment is transferred to the open ocean via channels that are periodically dredged to allow boat access to two small inland harbours. This positive affect of dredging has not received very much attention in existing literature. River water flowing to the channels during falling tide delivers sediment to these efficient pathways, where much of it bypasses the seagrass meadow at periods of time when sediment deposition would normally be the greatest. There is growing concern that ongoing land-cover changes and planned urbanization related to tourism and agriculture on the island may boost sediment/nutrients above a critical threshold, beyond that revealed in

  14. Standardized Chinese Formula Xin-Ke-Shu inhibits the myocardium Ca2+ overloading and metabolic alternations in isoproterenol-induced myocardial infarction rats

    Science.gov (United States)

    Liu, Yue-Tao; Zhou, Chao; Jia, Hong-Mei; Chang, Xing; Zou, Zhong-Mei

    2016-01-01

    Xin-Ke-Shu (XKS) is a traditional Chinese patent medicine used for treatment of coronary heart diseases in China. However, its mechanism of action is still unclear. In this paper, the mediation of XKS on the isoproterenol (ISO)-induced myocardial infarction (MI) rat were evaluated based on a tissue-targeted metabonomics in vitro/vivo. The result indicated that twelve metabolic pathways were involved in the therapeutic effect of XKS in vivo, where seven pathways were associated with the Ca2+ overloading mechanism. In agreement with regulation on metabolic variations, XKS markedly reversed the over-expressions of three involved proteins including phospholipase A2 IIA (PLA2 IIA), calcium/calmodulin-dependent protein kinase II (CaMK II) and Pro-Caspase-3. The metabolic regulations of XKS on H9c2 cell also partially confirmed its metabolic effect. These metabolic characteristics in vitro/vivo and western blotting analysis suggested that XKS protected from MI metabolic perturbation major via inhibition of Ca2+ overloading mechanism. Furthermore, 11 active ingredients of XKS exerted steady affinity with the three proteins through the molecular docking study. Our findings indicate that the metabonomics in vitro/vivo combined with western blotting analysis offers the opportunity to gain insight into the comprehensive efficacy of TCMs on the whole metabolic network. PMID:27457884

  15. Bu-Shen-Ning-Xin decoction suppresses osteoclastogenesis via increasing dehydroepiandrosterone to prevent postmenopausal osteoporosis.

    Science.gov (United States)

    Gui, Yuyan; Qiu, Xuemin; Xu, Yingping; Li, Dajin; Wang, Ling

    2015-06-01

    Bu-Shen-Ning-Xin decoction (BSNXD), a traditional Chinese medicine, has been used to prevent and treat age-related diseases such as postmenopausal osteoporosis (PMO) for decades. This study sought to investigate the underlying mechanisms of BSNXD in terms of receptor activation of nuclear factor κB ligand (RANKL)-induced osteoclastogenesis in vitro because of the critical roles of bone resorption in the development and progression of osteoporosis. In mice, serum levels of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), and 17-β-estradiol (E2) were evaluated with an enzyme immunoassay kit after ovariectomy. Levels of DHEA and DHEAS increased significantly following administration of BSNXD while the level of E2 did not. In addition, tartrate-resistance acid phosphatase staining showed that DHEA profoundly inhibited RANKL-induced osteoclastogenesis in vitro in a dose-dependent manner via estrogen receptor α (ERα) but not via estrogen receptor β or androgen receptors. Cytotoxicity was not detected in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. These data suggest that BSNXD prevents PMO by increasing DHEA via the ERαpathway to suppress osteoclastogenesis.

  16. Identification of Xin-repeat proteins as novel ligands of the SH3 domains of nebulin and nebulette and analysis of their interaction during myofibril formation and remodeling

    Science.gov (United States)

    Eulitz, Stefan; Sauer, Florian; Pelissier, Marie-Cecile; Boisguerin, Prisca; Molt, Sibylle; Schuld, Julia; Orfanos, Zacharias; Kley, Rudolf A.; Volkmer, Rudolf; Wilmanns, Matthias; Kirfel, Gregor; van der Ven, Peter F. M.; Fürst, Dieter O.

    2013-01-01

    The Xin actin-binding repeat–containing proteins Xin and XIRP2 are exclusively expressed in striated muscle cells, where they are believed to play an important role in development. In adult muscle, both proteins are concentrated at attachment sites of myofibrils to the membrane. In contrast, during development they are localized to immature myofibrils together with their binding partner, filamin C, indicating an involvement of both proteins in myofibril assembly. We identify the SH3 domains of nebulin and nebulette as novel ligands of proline-rich regions of Xin and XIRP2. Precise binding motifs are mapped and shown to bind both SH3 domains with micromolar affinity. Cocrystallization of the nebulette SH3 domain with the interacting XIRP2 peptide PPPTLPKPKLPKH reveals selective interactions that conform to class II SH3 domain–binding peptides. Bimolecular fluorescence complementation experiments in cultured muscle cells indicate a temporally restricted interaction of Xin-repeat proteins with nebulin/nebulette during early stages of myofibril development that is lost upon further maturation. In mature myofibrils, this interaction is limited to longitudinally oriented structures associated with myofibril development and remodeling. These data provide new insights into the role of Xin actin-binding repeat–containing proteins (together with their interaction partners) in myofibril assembly and after muscle damage. PMID:23985323

  17. Impact assessment of projected climate change on diffuse phosphorous loss in Xin'anjiang catchment, China.

    Science.gov (United States)

    Zhai, Xiaoyan; Zhang, Yongyong

    2017-11-30

    Diffuse nutrient loss is a serious threat to water security and has severely deteriorated water quality throughout the world. Xin'anjiang catchment, as a main drinking water source for Hangzhou City, has been a national concern for water environment protection with payment for watershed services construction. Detection of diffuse phosphorous (DP) pollution dynamics under climate change is significant for sustainable water quality management. In this study, the impact of projected climate change on DP load was analyzed using SWAT to simulate the future changes of diffuse components (carriers: water discharge and sediment; nutrient: DP) at both station and sub-catchment scales under three climate change scenarios (RCP2.6, RCP4.5, and RCP8.5). Results showed that wetting and warming years were expected with increasing tendencies of both precipitation and temperature in the two future periods (2020s: 2021~2030, 2030s: 2031~2040) except in the 2020s in the RCP2.6 scenario, and the annual average increasing ratios of precipitation and temperature reached - 1.79~3.79% and 0.48~1.27 °C, respectively, comparing with those in the baseline (2000s: 2001~2010). Climate change evidently altered annual and monthly average water discharge and sediment load, while it has a remarkable impact on the timing and monthly value of DP load at station scale. DP load tended to increase in the non-flood season at Yuliang due to strengthened nutrient flushing from rice land into rivers with increasing precipitation and enhanced phosphorous cycle in soil layers with increasing temperature, while it tended to decrease in the flood season at Yuliang and in most months at Tunxi due to restricted phosphorous reaction with reduced dissolved oxygen content and enhanced dilution effect. Spatial variability existed in the changes of sediment load and DP load at sub-catchment scale due to climate change. DP load tended to decrease in most sub-catchments and was the most remarkable in the RCP8

  18. Improving the Xin'anjiang hydrological model based on mass-energy balance

    Science.gov (United States)

    Fang, Yuan-Hao; Zhang, Xingnan; Corbari, Chiara; Mancini, Marco; Niu, Guo-Yue; Zeng, Wenzhi

    2017-07-01

    Conceptual hydrological models are preferable for real-time flood forecasting, among which the Xin'anjiang (XAJ) model has been widely applied in humid and semi-humid regions of China. Although the relatively simple mass balance scheme ensures a good performance of runoff simulation during flood events, the model still has some defects. Previous studies have confirmed the importance of evapotranspiration (ET) and soil moisture content (SMC) in runoff simulation. In order to add more constraints to the original XAJ model, an energy balance scheme suitable for the XAJ model was developed and coupled with the original mass balance scheme of the XAJ model. The detailed parameterizations of the improved model, XAJ-EB, are presented in the first part of this paper. XAJ-EB employs various meteorological forcing and remote sensing data as input, simulating ET and runoff yield using a more physically based mass-energy balance scheme. In particular, the energy balance is solved by determining the representative equilibrium temperature (RET), which is comparable to land surface temperature (LST). The XAJ-EB was evaluated in the Lushui catchment situated in the middle reach of the Yangtze River basin for the period between 2004 and 2007. Validation using ground-measured runoff data proves that the XAJ-EB is capable of reproducing runoff comparable to the original XAJ model. Additionally, RET simulated by XAJ-EB agreed well with moderate resolution imaging spectroradiometer (MODIS)-retrieved LST, which further confirms that the model is able to simulate the mass-energy balance since LST reflects the interactions among various processes. The validation results prove that the XAJ-EB model has superior performance compared with the XAJ model and also extends its applicability.

  19. Improving the Xin'anjiang hydrological model based on mass–energy balance

    Directory of Open Access Journals (Sweden)

    Y.-H. Fang

    2017-07-01

    Full Text Available Conceptual hydrological models are preferable for real-time flood forecasting, among which the Xin'anjiang (XAJ model has been widely applied in humid and semi-humid regions of China. Although the relatively simple mass balance scheme ensures a good performance of runoff simulation during flood events, the model still has some defects. Previous studies have confirmed the importance of evapotranspiration (ET and soil moisture content (SMC in runoff simulation. In order to add more constraints to the original XAJ model, an energy balance scheme suitable for the XAJ model was developed and coupled with the original mass balance scheme of the XAJ model. The detailed parameterizations of the improved model, XAJ-EB, are presented in the first part of this paper. XAJ-EB employs various meteorological forcing and remote sensing data as input, simulating ET and runoff yield using a more physically based mass–energy balance scheme. In particular, the energy balance is solved by determining the representative equilibrium temperature (RET, which is comparable to land surface temperature (LST. The XAJ-EB was evaluated in the Lushui catchment situated in the middle reach of the Yangtze River basin for the period between 2004 and 2007. Validation using ground-measured runoff data proves that the XAJ-EB is capable of reproducing runoff comparable to the original XAJ model. Additionally, RET simulated by XAJ-EB agreed well with moderate resolution imaging spectroradiometer (MODIS-retrieved LST, which further confirms that the model is able to simulate the mass–energy balance since LST reflects the interactions among various processes. The validation results prove that the XAJ-EB model has superior performance compared with the XAJ model and also extends its applicability.

  20. Antidepressant effects of Kai-Xin-San in fluoxetine-resistant depression rats

    Directory of Open Access Journals (Sweden)

    X.Z. Dong

    2017-08-01

    Full Text Available This study aimed to investigate the antidepressant effect and the mechanism of action of Kai-Xin-San (KXS in fluoxetine-resistant depressive (FRD rats. Two hundred male Wistar rats weighing 200±10 g were exposed to chronic and unpredictable mild stresses (CUMS for 4 weeks and given fluoxetine treatment simultaneously. The rats that did not show significant improvement in behavioral indexes were chosen as the FRD model rats. These rats were randomly divided into four groups: FRD model control; oral fluoxetine and aspirin; oral KXS at a dose of 338 mg·kg–1·day–1; and oral KXS at a dose of 676 mg·kg–1·day–1. Rats continued to be exposed to CUMS and underwent treatment once a day for 3 weeks, then cytokine (COX-2, IFN-γ, IL-1β, IL-2, IL-4, IL-6, IL-10, TGF-β, and TNF-α levels in the hippocampus and serum, and organ coefficients were measured. Both doses of KXS improved the crossing and rearing frequencies, sucrose-preference index, and body weight in FRD rats. KXS at a dose of 338 mg·kg–1·day–1reduced COX-2, IL-2, IL-6, TNF-α levels, increased IL-10 level in the hippocampus, and reduced IL-2 and TNF-α levels in serum. KXS at a dose of 676 mg·kg–1·day–1reduced TNF-α level in the hippocampus, reduced IL-2 and TNF-α levels in serum, and increased IFN-γ and IL-10 levels in the hippocampus and serum. There were no significant differences in organ-coefficients of the spleen among and between groups. The results suggested that oral administration of KXS in FRD rats was effective in improving behavior disorders by influencing various inflammatory pathways.

  1. [Yi lin cuo yao (Essentials of medical works) and its historical materials of medical exchanges between China and Korea].

    Science.gov (United States)

    Liang, Y

    2001-01-01

    Yi lin cuo yao, including 13 chapters and 128 categories, was written by Zheng Zhengxian and collated by Yang Lishou, both Korean imperial physicians in the 16 -- 17th centuries. With notation of a number of the Chinese and Korean medical books and materials in the first decade of the Li dynasty, this book is a comprehensive prescription work, very useful to clinical application. Especially with several points of the formulas from Zhong chao zhi wen fang (Sino -- Korean Prescriptions of Questioning) and zhong chao chuan xi fang (Sino -- Korean Prescriptions of Questioning) recorded in this book connected with Ren zhai zhi zhi fang lun (Renzhai's Comprehensive Prescriptions) in the Song dynasty. This book is an important record of the exchanges on medical ideas between China and Korea. However, it has nothing to do with Yi xue yi wen (Questions on Medicine) by Fu Maoguang, which records the questions and answers between Chinese and Korean officials.

  2. A Rutile Chevron Modulation in Delafossite-Like Ga3-xIn3TixO9+x/2.

    Science.gov (United States)

    Rickert, Karl; Boullay, Philippe; Malo, Sylvie; Caignaert, Vincent; Poeppelmeier, Kenneth R

    2016-05-02

    The structure solution of the modulated, delafossite-related, orthorhombic Ga3-xIn3TixO9+x/2 for x = 1.5 is reported here in conjunction with a model describing the modulation as a function of x for the entire system. Previously reported structures in the related A3-xIn3TixO9+x/2 (A = Al, Cr, or Fe) systems use X-ray diffraction to determine that the anion lattice is the source of modulation. Neutron diffraction, with its enhanced sensitivity to light atoms, offers a route to solving the modulation and is used here, in combination with precession electron diffraction tomography (PEDT), to solve the structure of Ga1.5In3Ti1.5O9.75. We construct a model that describes the anion modulation through the formation of rutile chevrons as a function of x. This model accommodates the orthorhombic phase (1.5 ≤ x ≤ 2.1) in the Ga3-xIn3TixO9+x/2 system, which transitions to a biphasic mixture (2.2 ≤ x ≤ 2.3) with a monoclinic, delafossite-related phase (2.4 ≤ x ≤ 2.5). The optical band gaps of this system are determined, and are stable at ∼3.4 eV before a ∼0.4 eV decrease between x = 1.9 and 2.0. After this decrease, stability resumes at ∼3.0 eV. Resistance to oxidation and reduction is also presented.

  3. Understanding the function of ancient Chinese calendar from The Book of History: Yao's Story - a discussion with the author of the truth of astronomy and astrology in ancient China.

    Science.gov (United States)

    Xuan, Huancan

    From his thorough study of The Book of History: Yao's Story, the author of The Truth of Astronomy and Astrology in Ancient China got his opinion that starting from the Yao's era (around 2200 B.C.) the ancient Chinese calendar was no longer made for farming, but was made "to arrange the governors' important political agenda". The follwing essay studies this question from several different points of view.

  4. The proprotein convertase subtilisin/kexin type 9 gene E670G polymorphism and serum lipid levels in the Guangxi Bai Ku Yao and Han populations

    Directory of Open Access Journals (Sweden)

    Li Qing

    2011-01-01

    Full Text Available Abstract Background Proprotein convertase subtilisin-like kexin type 9 (PCSK9 plays a key role in regulating plasma low-density lipoprotein cholesterol (LDL-C levels. However, the association of E670G (rs505151 polymorphism in the PCSK9 gene and serum lipid levels is inconsistent in several previous studies. The present study was undertaken to detect the association of PCSK9 E670G polymorphism and several environmental factors with serum lipid levels in the Guangxi Bai Ku Yao and Han populations. Methods A total of 649 subjects of Bai Ku Yao and 646 participants of Han were randomly selected from our previous samples. Genotypes of the PCSK9 E670G polymorphism were determined via polymerase chain reaction and restriction fragment length polymorphism combined with gel electrophoresis, and then confirmed by direct sequencing. Results Serum levels of total cholesterol, high-density lipoprotein cholesterol (HDL-C, LDL-C, and apolipoprotein (Apo AI were lower in Bai Ku Yao than in Han (P P P 3.20 mmol/L, P P P P P P P P Conclusions The PCSK9 E670G polymorphism is mainly associated with some serum lipid parameters in the Han population. The G allele carriers had higher serum HDL-C and ApoAI levels in males, and lower serum ApoB levels and higher the ApoAI/ApoB ratio in females than the G allele noncarriers.

  5. Effect of "Dang-Qui-Shao-Yao-San" a Chinese medicinal prescription for dysmenorrhea on uterus contractility in vitro.

    Science.gov (United States)

    Hsu, C-S; Yang, J-K; Yang, L-L

    2006-01-01

    Dysmenorrhea is directly related to elevated level of prostaglandin F(2)alpha (PGF(2)alpha), and is treated with nonsteroid anti-inflammatory drugs. Though efficacy of the latter is rapid, the effect is temporary, and they cause many side effects to the liver, kidney and digestive system. Because of this, Chinese medicinal therapy is being considered as a feasible alternative medicine. In this study, Dang-Qui-Shao-Yao-San (DQSYS), one of Chinese medicinal prescriptions was selected. A 50% alcohol solution was used to extract the active ingredients and create a freeze-dried product. Using rat uterine smooth muscle in vitro, DQSYS was used to suppress spontaneous contractions and PGF(2)alpha induced contractions. Then acetylcholine, ergonovine, propranolol, oxytocin and KCl were used to analyze the physiological mechanisms. The results show that DQSYS has the antagonistic action on both PGF(2)alpha and Ach induced uterine contraction. Furthermore, it has the antagonistic effect on contraction caused by KCl-depolarization. These actions may be the major mechanism of the beneficial effect of Chinese prescription in treating dysmenorrhea.

  6. A Chinese Herbal Medicine, Jia-Wei-Xiao-Yao-San, Prevents Dimethylnitrosamine-Induced Hepatic Fibrosis in Rats

    Directory of Open Access Journals (Sweden)

    Shu-Chen Chien

    2014-01-01

    Full Text Available Jia-wei-xiao-yao-san (JWXYS is a traditional Chinese herbal medicine that is widely used to treat neuropsychological disorders. Only a few of the hepatoprotective effects of JWXYS have been studied. The aim of this study was to investigate the hepatoprotective effects of JWXYS on dimethylnitrosamine- (DMN- induced chronic hepatitis and hepatic fibrosis in rats and to clarify the mechanism through which JWXYS exerts these effects. After the rats were treated with DMN for 3 weeks, serum glutamic oxaloacetic transaminase (SGOT and serum glutamic pyruvic transaminase (SGPT levels were significantly elevated, whereas the albumin level decreased. Although DMN was continually administered, after the 3 doses of JWXYS were orally administered, the SGOT and SGPT levels significantly decreased and the albumin level was significantly elevated. In addition, JWXYS treatment prevented liver fibrosis induced by DMN. JWXYS exhibited superoxide-dismutase-like activity and dose-dependently inhibited DMN-induced lipid peroxidation and xanthine oxidase activity in the liver of rats. Our findings suggest that JWXYS exerts antifibrotic effects against DMN-induced chronic hepatic injury. The possible mechanism is at least partially attributable to the ability of JWXYS to inhibit reactive-oxygen-species-induced membrane lipid peroxidation.

  7. Effects of Jia-Wei-Xiao-Yao-San on the Peripheral and Lymphatic Pharmacokinetics of Paclitaxel in Rats

    Directory of Open Access Journals (Sweden)

    Mei-Ling Hou

    2016-01-01

    Full Text Available Paclitaxel is effective against breast cancer. The herbal medicine, Jia-Wei-Xiao-Yao-San (JWXYS, is the most frequent prescription used to relieve the symptoms of breast cancer treatments. The aim of the study was to investigate the herb-drug interaction effects of a herbal medicine on the distribution of paclitaxel to lymph. A validated ultraperformance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS method was used to determine the paclitaxel levels in rat plasma and lymph after intravenous infusion of paclitaxel alone with or without 7 days of JWXYS pretreatment. The pharmacokinetic results indicate that paclitaxel concentrations in plasma exceeded those in lymph by approximately 3.6-fold. The biodistribution of paclitaxel from plasma to lymph was 39±5%; however, this increased to 45±4% with JWXYS pretreatment. With JWXYS pretreatment, the AUC and Cmax of paclitaxel in plasma were significantly reduced by approximately 1.5-fold, compared to paclitaxel alone. Additionally, JWXYS decreased the AUC and Cmax of paclitaxel in lymph. However, the lymph absorption rate of paclitaxel with or without JWXYS pretreatment was not significantly changed (27±3 and 30±2%, resp.. Our findings demonstrate that when paclitaxel is prescribed concurrently with herbal medicine, monitoring of the blood pharmacokinetics of paclitaxel is recommended.

  8. CARDIOPROTECTIVE ROLES OF THE CHINESE MEDICINAL FORMULA BAO-XIN-TANG ON ACUTE MYOCARDIAL INFARCTION IN RATS.

    Science.gov (United States)

    Wang, Yang; Wang, Weihao; Peng, Weijun; Liu, Weiping; Cai, Weijun; Xia, Zian; Zhang, Honggeng; Xing, And Zhihua

    2017-01-01

    Bao-Xin-Tang (BXT) is a traditional Chinese medicinal formula used for the treatment of coronary heart disease and known to have favorable therapeutic benefits. The current study was designed to determine whether BXT has a cardioprotective role for acute myocardial infarction. The underlying mechanisms were also explored. The Sprague-Dawley rat model of acute myocardial infarction was established by occluding the left anterior descending branch of the coronary artery. After a 3-h ischemic period, we determined the myocardial infarction size, inflammatory components, and antioxidant activities. The data showed that BXT could reduce the infarction size and lower the levels of C-reactive protein, interleukin-6, and myeloperoxidase, and increase the activities of superoxide dismutase and the anti-inflammatory cytokine, interleukin-10. These results indicate that administration of BXT, following acute myocardial infarction, could reduce infarct size. The effects of BXT may be related to its anti-inflammatory and anti-oxidative properties.

  9. U-Pb geochronology, geochemistry, and H-O-S-Pb isotopic compositions of the Leqingla and Xin'gaguo skarn Pb-Zn polymetallic deposits, Tibet, China

    Science.gov (United States)

    Wang, Liqiang; Cheng, Wenbin; Tang, Juxing; Kang, Haoran; Zhang, Yan; Li, Zhuang

    2016-01-01

    The Leqingla and Xin'gaguo deposits are two representative skarn Pb-Zn polymetallic deposits of the Gangdese Pb-Zn polymetallic belt, Tibet, China. LA-ICP-MS zircon U-Pb dating of the mineralization-related biotite granites from both the Leqingla and Xin'gaguo deposits yielded weighted mean ages of 60.8 Ma and 56.5 Ma, respectively, which can be inferred as their mineralization ages. The Leqingla biotite granite is characterized by high Al2O3, total Fe, Na2O, and low K2O. In comparison, the Xin'gaguo biotite granite is characterized by relative higher K2O but lower Al2O3, total Fe, and Na2O. Geochemical and mineralogical characteristics indicate that the Leqingla and Xin'gaguo biotite granites are calc-alkaline I-type granite and High K calc-alkaline I-type granite, respectively. Both the Leqingla and Xin'gaguo biotite granites are enrichment in LREE and LILEs and depletion in HFSEs, and they were formed at the India-Asia collision stage. δ18O and δD values for the Leqingla and Xin'gaguo deposits are -8.8‰ to 5.3‰ and -140.4‰ to -90.1‰, -4.5‰ to 7.0‰ and -117.3‰ to -81.0‰, respectively, indicating magma fluids mixed with meteoric water in ore-forming fluids. δ34S values (-11.6‰ to -0.3‰) of ore sulfides from the Leqingla deposit show characteristics of biogenetic sulfur isotope compositions, suggesting sulfur for the Leqingla deposit were sourced from wall rocks of the Mengla and Luobadui Formation, which are rich in organic materials. δ34S values of ore sulfides from the Xin'gaguo deposits show bimodal distribution (-5.0‰ to -1.6‰ and 1.6-2.1‰), indicating sulfur in the Xin'gaguo deposit were derived from both wall rocks and magma. In the Leqingla deposit, most ore sulfides have the similar Pb isotopic compositions with that of the mineralization-related biotite granite, suggesting the biotite granite supplied most of the ore-forming metals. Pb isotopic compositions of ore sulfides and Hf isotopic compositions of biotite granite show

  10. Large refrigeration capacities near room temperature in Ni{sub 2}Mn{sub 1−x}Cr{sub x}In

    Energy Technology Data Exchange (ETDEWEB)

    Brock, Jeffrey; Khan, Mahmud, E-mail: khanm2@miamioh.edu

    2017-03-01

    We report on the observation of large refrigeration capacities near room temperature in Ni{sub 2}Mn{sub 1−x}Cr{sub x}In Heusler alloys. The alloys exhibit the L2{sub 1} cubic crystal structure and undergo a second order ferromagnetic to paramagnetic phase transition. The respective Curie temperatures vary with Cr concentration from 315 K to 290 K. Net refrigerant capacities of up to 60 J/kg and 168 J/kg are observed in the alloys for applied magnetic fields of 20 kOe and 50 kOe, respectively. Due to the second order phase transition, the materials do not exhibit any hysteresis loss or other problems usually associated with materials exhibiting first order phase transitions. The observed refrigeration capacities in Ni{sub 2}Mn{sub 1−x}Cr{sub x}In are higher than those observed in many Heusler alloys with first order magnetic transitions. - Highlights: • The magnetic and magnetocaloric properties of Ni{sub 2}Mn{sub 1−x}Cr{sub x}In have been investigated. • The materials exhibit ferromagnetic transitions and associated magnetocaloric effects near room temperature. • The materials exhibit refrigeration capacities that are superior to those of Heusler alloys with first order phase transition.

  11. [Textual research on Guang dong xin yu (New Sayings of Guangdong) quoted in Ben cao gang mu shi yi (Supplements to Compendium of Materia Medica].

    Science.gov (United States)

    Zhang, Ruixian; Zhang, Wei; Li, Jian; Liang, Fei

    2014-05-01

    Altogether 15 terms for Guang dong xin yu (New Sayings of Guangdong) were used in Ben cao gang mu shi yi (Supplements to Compendium of Materia Medica), including Yue yu (Cantonese sayings), Chong yu (Sayings from Insect Drug), Jie yu (Sayings from Crustacean Drug), Xin yu (New Sayings), Yue hai xiang yu (Fragrant Sayings from Cantonese Region), Yue zhi mu yu (Sayings from Plants in Cantonese Annals), Guang dong suo yu (Trivial Sayings from Guangdong), Yue shan lu (Records of Cantonese Mountains), Yue lu (Cantonese Records), Jiao guang lu (Joint Guangdong Records), Yue cao zhi (Records of Cantonese Grasses), Guang guo lu (Records of Guangdong Fruits), Nan yue suo ji (Trivial Records of Southern Canton), Guang zhi (Guangdong Records), Yue zhi (Cantonese Records) etc. dealing with 57 sorts of drugs (with individual overlapping ones), the author of Xin yu was Qu Dajun, a surviving fogy of the Ming Dynasty actively involved in the activities to restore the old dynasty and resist the Qing Dynasty, and was persecuted in the literary inquisition in which his works were burnt so that Zhao Xuemin, when quoting his texts, had to go in a roundabout way.

  12. Donor states in a semimagnetic Cd1 -xinMnxin Te /Cd1 -xoutMnxout Te Double Quantum Well

    Science.gov (United States)

    Kalpana, Panneer Selvam; Nithiananthi, Perumal; Jayakumar, Kalyanasundaram

    2017-02-01

    The theoretical investigation has been carried out on the binding energy of donor associated with the electrons confined in a Cd1 -xinMnxin Te /Cd1 -xoutMnxout Te Double Quantum Well (DQW) as a function of central barrier width for various well dimensions and impurity locations in the barrier and the well. The magnetic field can act as a tool to continuously change the interwell coupling inside this DQW systems and its effect on donor binding has also been studied. Moreover, the polaronic corrections, which is due to the strong exchange interaction between the magnetic moment of Mn2+ ion and the spin of the confined carrier, to the binding energy of the hydrogenic donor impurity has also been estimated with and without the application of magnetic field. The binding energy of the donor impurity is determined by solving the Schrodinger equation variationally in the effective mass approximation and the effect due to Bound Magnetic Polaron (BMP) is included using mean field theory with the modified Brillouin function. The results are reported and discussed.

  13. Hybridizing scholastic psychology with Chinese medicine: a seventeenth-century Chinese Catholic's conceptions of xin (mind and heart).

    Science.gov (United States)

    Zhang, Qiong

    2008-01-01

    This paper explores the dynamics of cultural interactions between early modern China and Europe initiated by the Jesuits and other Catholic missionaries through a case study of Wang Honghan, a seventeenth-century Chinese Catholic who systematically sought to integrate European learning introduced by the missionaries with pre-modern Chinese medicine. Focusing on the ways in which Wang combined his Western and Chinese sources to develop and articulate his views on xin (mind and heart), this paper argues that Wang arrived at a peculiar hybrid between scholastic psychology and Chinese medicine, not so much through a course of haphazard misunderstanding as through his conscious and patterned use and abuse of his Western sources, which was motivated most possibly by a wish to define a theoretical position that most suited his social roles as a Catholic convert and a Chinese medical doctor. Thus, rather than seeing Wang as an epitome of"transmission failure," this paper offers it as a showcase for the tremendous dynamism and creativity occurring at this East-West "contact zone as representatives of both cultures sought to appropriate and transform the symbolic and textual resources of the other side.

  14. Effect of kai xin san on learning and memory in a rat model of paradoxical sleep deprivation.

    Science.gov (United States)

    Hu, Yuan; Liu, Ming; Liu, Ping; Yan, Juan-Juan; Liu, Ming-Yue; Zhang, Gang-Qiang; Zhou, Xiao-Jiang; Yu, Bing-Ying

    2013-04-01

    The present study aimed to evaluate the effect of kai xin san (KXS, at doses of 500, 250, and 125 mg/kg body weight per day), a well-known traditional Chinese medicine, on learning and memory in paradoxical sleep deprivation (PSD)-induced cognition deficit rats. Two behavior tests (the Open Field test and the Morris water maze task) were used for testing the effects of KXS on a PSD-induced learning and memory deficit model. Furthermore, its effect on the glutamic acid (GLU) and γ-amino-butyric acid (GABA) levels in the brain tissue, brain-derived neurotrophic factor (BDNF), cyclic AMP response element binding protein (CREB), and phosphorylated-CREB (p-CREB) expression in the hippocampus was also tested. KXS exerted the greatest cognition against the 48 h PSD-induced cognitive deficit and these effects may be mediated by decreasing the GLU and GABA levels and increasing the levels of BDNF, CREB, and p-CREB. This study indicates that the effect of KXS on learning and memory in a rat model of PSD could be associated with the modulation of neurotransmitter levels and the expression of some genes in the brain that contribute to memory functions.

  15. YAO NGUETTIA.pmd

    African Journals Online (AJOL)

    SECRETARIAT

    Le palmier à huile est une culture de rente bien développée dans la zone forestière du sud de la. Côte d'Ivoire ... Les différents programmes de développement de la culture du palmier à huile initiés par l'Etat n'ont jamais pris ... à la même Station désormais CNRA La Mé en. 1999 pour la plantation de 2000 et en 2001 pour.

  16. Efficacy of Modified Ban Xia Xie Xin Decoction on Functional Dyspepsia of Cold and Heat in Complexity Syndrome: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Luqing Zhao

    2013-01-01

    Full Text Available Background. Chinese herbal medicine (CHM has been used in China and elsewhere to treat patients with functional dyspepsia (FD. However, controlled studies supporting the efficacy of such treatment are lacking. Objective. To assess the efficacy and safety of modified Ban xia xie xin decoction in patients with FD of cold and heat in complexity syndrome. Methods. We performed a randomized, double-blind, placebo-controlled trial involving patients from five centers. Patients with FD of cold and heat in complexity syndrome (n=101 were randomly assigned to groups given either CHM modified Ban Xia Xie Xin decoction or placebo in a 2 : 1 ratio. Herbal or placebo granules were dissolved in 300 mL of boiled water cooled to 70°C. Patients in both groups were administered 150 mL (50°C twice daily. The trial included a 4-week treatment period and a 4-week followup period. The primary outcomes were dyspepsia symptom scores, measured by the total dyspepsia symptom scale and the single dyspepsia symptom scale at weeks 0, 1, 2, 3, 4, and 8. Results. Compared with patients in the placebo group, patients in the CHM group showed significant improvements according to the total and single dyspepsia symptom scores obtained from patients (P<0.01 and investigators (P<0.01. Conclusions. CHM modified Ban Xia Xie Xin decoction appears to offer symptomatic improvement in patients with FD of cold and heat in complexity syndrome. Trial Registration. Chinese Clinical Trial Registry (ChiCTR: ChiCTR-TRC-10001074.

  17. [Ecosystem service and economic valuation in the upper reaches of Xin' an River, Anhui, China for mitigating phosphorus nonpoint source pollution].

    Science.gov (United States)

    He, Fang; Wu, Nan; Fang, Xiang-long; Gao, Ji-xi; Zhou, Xiao-tie; Feng, Chao-yang

    2015-04-01

    A model of phosphorus purification in a watershed was established based on the export coefficient and purification index of phosphorus in different types of land cover. The model was employed to simulate the economic value of the ecosystem service with the expected water quality standard and marginal cost of pollutant purification of the upper reaches of Xin' an River of Anhui, China. The results revealed that from 2000 to 2010, some farmland outside the Tunxi, Jixi, Shexian, Yixian and Xiuning was converted to built-up land. The total amount of phosphorus exported to the upper Xin' an River decreased a little, and the main source of phosphorus pollution was farmland and built-up land. More than half of the exported phosphorus was efficiently purified by different types of land cover via flow accumulation. The pattern of purification and export of highly concentrated phosphorus showed the same trend which occurred in the northern part of the watershed including the Yangzhi River, Fengle River and Hengjiang River. Forestland and grassland did not efficiently purify phosphorus in the watershed owing to the irrational distribution of existing land cover. The total service value was 3.80 and 3.31 million Yuan in 2000 and 2010, respectively.

  18. Synthesis and Physical Properties of Nanocomposites (SnO2x(In2O31-x (x = 0 – 1 for Gas Sensors and Optoelectronics

    Directory of Open Access Journals (Sweden)

    Stanislav REMBEZA

    2010-11-01

    Full Text Available Experimental results on synthesis of thin film (< 1 μm nanocomposites (SnO2x(In2O31-x in the whole range of x = (0 – 1 mass. % are presented. Film nanocomposites were prepared by high-frequency magnetron sputtering of metal oxide targets in the controlled ambient Ar+O2. Films were deposited on the hot substrate (400 0C and investigated by X-ray phase analysis, atomic-force microscopy, optical and electrical methods. Influence of synthesis regimes and film composition on the grain size of crystals, the band-gap width, the transparency in the visible range of light, concentration and mobility of free charge carriers were determined. It was shown that films with composition (SnO2x(In2O31-x x = 0.9 are perspective for using as gas sensors, films of the same composition but with x = 0.1 can be applied as transparent current conducting electrodes for solar cells.

  19. Multimedia over cognitive radio networks algorithms, protocols, and experiments

    CERN Document Server

    Hu, Fei

    2014-01-01

    PrefaceAbout the EditorsContributorsNetwork Architecture to Support Multimedia over CRNA Management Architecture for Multimedia Communication in Cognitive Radio NetworksAlexandru O. Popescu, Yong Yao, Markus Fiedler , and Adrian P. PopescuPaving a Wider Way for Multimedia over Cognitive Radios: An Overview of Wideband Spectrum Sensing AlgorithmsBashar I. Ahmad, Hongjian Sun, Cong Ling, and Arumugam NallanathanBargaining-Based Spectrum Sharing for Broadband Multimedia Services in Cognitive Radio NetworkYang Yan, Xiang Chen, Xiaofeng Zhong, Ming Zhao, and Jing WangPhysical Layer Mobility Challen

  20. Effect of TongXie-YaoFang on Cl− and HCO3- Transport in Diarrhea-Predominant Irritable Bowel Syndrome Rats

    Directory of Open Access Journals (Sweden)

    Xiaofang Lu

    2016-01-01

    Full Text Available TongXie-YaoFang (TXYF can effectively alleviate the symptoms of diarrhea-predominant irritable bowel syndrome (D-IBS patients. However, the curative mechanism has not been fully clarified. The study was designed to investigate the effect of TXYF on the colonic ion transport induced by serotonin (5-HT in D-IBS rats. A method of multiple stress (neonatal maternal separation (NMS combined with restraint stress (RS was used to induce the D-IBS model. The model rats were randomly divided into two groups: NMS + RS group and TXYF-formula group, and the normal control (no handling rats were classified as NH group. In the NMS + RS group, the change of short-circuit current (ΔIsc induced by 5-HT was lower than that in the NH and TXYF-formula groups. After removing of the extracellular Cl− or HCO3- or basolateral Na+ or blocking the cystic fibrosis transmembrane conductance regulator (CFTR, Na+-K+-2Cl− cotransporter (NKCC, Na+-HCO3- cotransporter, Cl-/HCO3- exchanger, K+ channel, or Na+/K+-ATPase, respectively, there was no difference in 5-HT-induced ΔIsc among the three groups. These data suggest that TXYF can regulate 5-HT-induced Cl− and HCO3- secretion, possibly mediated by the combined action of CFTR, NKCC, Na+-HCO3- cotransporter, Cl-/HCO3- exchanger, K+ channel, and Na+/K+-ATPase.

  1. Xiao Yao San Improves Depressive-Like Behavior in Rats through Modulation of β-Arrestin 2-Mediated Pathways in Hippocampus

    Directory of Open Access Journals (Sweden)

    Xiaoxia Zhu

    2014-01-01

    Full Text Available Xiao Yao San (XYS is a classical Chinese medicine formula that has been widely used to treat mood disorders for hundreds of years. To confirm the effect of XYS and better understand its underlying mechanism, high-performance liquid chromatography-mass spectrometry analysis-based quality control of XYS extracts and proteomics-based identification of differential proteins in the hippocampus were adopted in social isolation and chronic unpredictable mild stress- (CUMS- treated rats. The depressive-like behavior of rats induced by CUMS resembled the manifestation of human depression. The upregulated corticosterone (CORT and urocortin 2 (UCN2 levels demonstrated the existence of hypothalamic-pituitary-adrenal (HPA axis hyperactivity. XYS was effective in ameliorating the depressive-like behavior and downregulating UCN2 and CORT. XYS decreased the expression of serine/threonine-protein phosphatase 2A subunit B and increased the expression of β-arrestin 2. The expressions of brain-derived neurotrophic factor (BDNF, tyrosine receptor kinase B (TrkB, and mammalian target of rapamycin (mTOR were also elevated by XYS. In conclusion, XYS improves social isolation and CUMS-induced depressive-like behavior and ameliorates HPA hyperactivation through the downregulation of corticotrophin releasing hormone (CRH receptor 2. The upregulation of BDNF/TrkB and the phosphorylation of mTOR require β-arrestin 2 as a scaffold to regulate stress signaling.

  2. Xiao Yao San Improves Depressive-Like Behaviors in Rats with Chronic Immobilization Stress through Modulation of Locus Coeruleus-Norepinephrine System

    Directory of Open Access Journals (Sweden)

    Xiu-Fang Ding

    2014-01-01

    Full Text Available Most research focuses on the hypothalamic-pituitary-adrenal (HPA axis, hypothalamus-pituitary-thyroid (HPT axis, and hypothalamus-pituitary-gonadal (HPGA axis systems of abnormalities of emotions and behaviors induced by stress, while no studies of Chinese herbal medicine such as Xiao Yao San (XYS on the mechanisms of locus coeruleus-norepinephrine (LC-NE system have been reported. Therefore, experiments were carried out to observe mechanism of LC-NE system in response to chronic immobilization stress (CIS and explore the antidepressant effect of XYS. Rat model was established by CIS. LC morphology in rat was conducted. The serum norepinephrine (NE concentrations and NE biosynthesis such as tyrosine hydroxylase (TH, dopamine-β-hydroxylase (DBH, and corticotrophin-releasing-factor (CRF in LC were determined. Results showed that there were no discernible alterations in LC in rats. The serum NE concentrations, positive neurons, mean optical density (MOD, and protein levels of TH, DBH, and CRF in model group were significantly increased compared to the control group. But XYS-treated group displayed a significantly decreased in NE levels and expressions of TH, DBH, and CRF compared to the model group. In conclusion, CIS can activate LC-NE system to release NE and then result in a significant decrease in rats. XYS treatment can effectively improve depressive-like behaviors in rats through inhibition of LC-NE neurons activity.

  3. Post-synthetic transformation of a Zn(ii) polyhedral coordination network into a new supramolecular isomer of HKUST-1.

    Science.gov (United States)

    Chen, Yao; Wojtas, Lukasz; Ma, Shengqian; Zaworotko, Michael J; Zhang, Zhenjie

    2017-08-03

    A Zn-based porphyrin containing metal-organic material (porphMOM-1) was transformed into a novel Cu-based porphyrin-encapsulating metal-organic material (porph@HKUST-1-β) via a one-pot post-synthetic modification (PSM) process involving both metal ion exchange and linker installation of trimesic acid. HKUST-1-β is the first example of yao topology and is to our knowledge the first supramolecular isomer of the archetypal coordination network HKUST-1.

  4. Verification of Correspondence Assertions in a Calculus for Mobile Ad Hoc Networks

    DEFF Research Database (Denmark)

    Hüttel, Hans; Kühnrich, Morten; Godskesen, Jens Christian

    2009-01-01

    We introduce a novel process calculus called DBSPI (distributed broadcast SPI-calculus) which models mobile ad hoc networks (MANET). The calculus is a cryptographic broadcast calculus with locations and migration. Communication and migration are limited to neighborhoods. Neighborhood definitions...... are explicitly part of the syntax allowing dynamic extension using bound identifiers. In this semantic setting we study authentication of agents in MANET protocols. A safety property dealing with authentication correspondence assertions is defined. Later a dependent type and effect system is given...... and it is shown to be sound, i.e. protocols which are typeable are also safe. This result is lifted to open systems which involves Dolev-Yao attackers. Our Dolev-Yao attacker may use public keys for encryption and can attack any neighborhood it wishes. Our technique is applied to the Mobile IP registration...

  5. [Comparative study of theoretical literature on cold pathogenic disease in Wai tai mi yao fang (Arcane Essentials from the Imperial Library) and Tai ping sheng hui fang (Taiping Holy Prescriptions for Universal Relief)].

    Science.gov (United States)

    Zhang, Huirui; Liang, Yongxuan

    2014-09-01

    In the Wai tai mi yao fang (Arcane Essentials from the Imperial Library) compiled in 752, its portion on cold pathogenic disorders embodies the achievements before the mid Tang Dynasty, whereas that in the Tai ping sheng hui fang (Taiping Holy Prescriptions for Universal Relief), compiled in 992 embodies those before the early Song Dynasty. Comparison on the theory of cold disorders in both books reveal that, during the 2 centuries period from mid Tang to early Song Dynasties, the texts as a carrier for the transmission of such theory in both show no distinct changes, but only with minor revisions and improvements.

  6. A Standardized Chinese Herbal Decoction, Kai-Xin-San, Restores Decreased Levels of Neurotransmitters and Neurotrophic Factors in the Brain of Chronic Stress-Induced Depressive Rats

    Directory of Open Access Journals (Sweden)

    Kevin Yue Zhu

    2012-01-01

    Full Text Available Kai-xin-san (KXS, a Chinese herbal decoction being prescribed by Sun Simiao in Beiji Qianjin Yaofang about 1400 years ago, contains Ginseng Radix et Rhizoma, Polygalae Radix, Acori tatarinowii Rhizoma, and Poria. KXS has been used to treat stress-related psychiatric disease with the symptoms of depression and forgetfulness in ancient China until today. However, the mechanism of its antidepression action is still unknown. Here, the chronic mild-stress-(CMS- induced depressive rats were applied in exploring the action mechanisms of KXS treatment. Daily intragastric administration of KXS for four weeks significantly alleviated the CMS-induced depressive symptoms displayed by enhanced sucrose consumption. In addition, the expressions of those molecular bio-markers relating to depression in rat brains were altered by the treatment of KXS. These KXS-regulated brain biomarkers included: (i the levels of dopamine, norepinephrine, and serotonin (ii the transcript levels of proteins relating to neurotransmitter metabolism; (iii the transcript levels of neurotrophic factors and their receptors. The results suggested that the anti-depressant-like action of KXS might be mediated by an increase of neurotransmitters and expression of neurotrophic factors and its corresponding receptors in the brain. Thus, KXS could serve as alternative medicine, or health food supplement, for patients suffering from depression.

  7. A Modified Chinese Herbal Decoction (Kai-Xin-San Promotes NGF-Induced Neuronal Differentiation in PC12 Cells via Up-Regulating Trk A Signaling

    Directory of Open Access Journals (Sweden)

    Lu Yan

    2017-12-01

    Full Text Available Kai-Xin-San (KXS, a Chinese herbal decoction, has been applied to medical care of depression for thousands of years. It is composed of two functional paired-herbs: Ginseng Radix et Rhizoma (GR-Polygalae Radix (PR and Acori Tatarinowii Rhizoma (ATR-Poria (PO. The compatibility of the paired-herbs has been frequently changed to meet the criteria of syndrome differentiation and treatment variation. Currently, a modified KXS (namely KXS2012 was prepared by optimizing the combinations of GR-PR and ATR-PO: the new herbal formula was shown to be very effective in animal studies. However, the cellular mechanism of KXS2012 against depression has not been fully investigated. Here, the study on KXS2012-induced neuronal differentiation in cultured PC12 cells was analyzed. In PC12 cultures, single application of KXS2012 showed no effect on the neuronal differentiation, but which showed robust effects in potentiating nerve growth factor (NGF-induced neurite outgrowth and neurofilament expression. The potentiating effect of KXS2012 was mediated through NGF receptor, tropomyosin receptor kinase (Trk A: because the receptor expression and activity was markedly up-regulated in the presence of KXS2012, and the potentiating effect was blocked by k252a, an inhibitor of Trk A. Our current results in cell cultures fully support the therapeutic efficacy of KXS2012 against depression.

  8. A High Content Screening Assay to Identify Compounds with Anti-Epithelial-Mesenchymal Transition Effects from the Chinese Herbal Medicine Tong-Mai-Yang-Xin-Wan

    Directory of Open Access Journals (Sweden)

    Ningning Liu

    2016-10-01

    Full Text Available Chronic kidney disease (CKD is a worldwide health problem with growing prevalence in developing countries. Renal tubular epithelial-mesenchymal transition (EMT is a critical step and key factor in the development of this condition. Renal tubulointerstitial fibrosis is a basic pathological change at the later stages of the disease. Therefore, blocking the development of EMT could be a critical factor in curing CKD. We have established a cell-based high-content screening (HCS method to identify inhibitors of EMT in human proximal tubular epithelial (HK-2 cells by automatic acquisition and processing of dual-fluorescent labeled images. With the aid of chromatographic separation and mass spectrometry, we achieved the rapid and reliable screening of active compounds from the Chinese herbal medicine Tong-Mai-Yang-Xin-Wan (TMYX for treating EMT. Five fractions were found to exert anti-EMT activity and were further identified by liquid chromatography coupled with tandem mass spectrometry. Glycyrrhizic acid, glyasperin A, and licorisoflavan A were found to inhibit EMT. The proposed approach was successfully applied to screen active compounds from TMYX on TGF-β1-stimulated HK-2 cells and may offer a new means for identifying lead compounds for treating EMT from registered Chinese herbal medicines.

  9. Protective effect of the ultra-filtration extract from Xin Mai Jia on human aortic smooth muscle cell injury induced by hydrogen peroxide

    Science.gov (United States)

    WAN, JIA; YIN, YALING; SUN, RUILI; PAN, GUOPIN; LI, PENG; JIA, YANLONG; WAN, GUANGRUI; LIU, ZHANG-SUO

    2014-01-01

    The aim of the present study was to explore whether an ultra-filtration extract from Xin Mai Jia (XMJ), a Chinese medicinal formulation, has a protective effect on human aortic smooth muscle cell (HASMC) injury models induced by hydrogen peroxide (H2O2), and to consider the mechanism and efficacy of the therapeutic action of XMJ on atherosclerosis. HASMCs were injured by H2O2 and then exposed to various concentrations of XMJ. The morphological changes, growth, proliferation, migration and cytokine release of HASMCs were detected using 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT), an enzyme-linked immunosorbent assay and a scratch adhesion test. H2O2 significantly promoted the proliferation of HASMCs. The ultra-filtration extract from XMJ was observed to significantly attenuate the morphological changes of injured HASMCs, reduce the expression levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), interleukin (IL)-1, IL-6 and nuclear factor (NF)-κB, and increase the expression levels of matrix metalloproteinase (MMP)-2 and tissue inhibitor of metalloproteinase (TIMP). XMJ has clear anti-inflammatory and antioxidant effects, and significantly inhibits the proliferation and migration of HASMCs. PMID:24348756

  10. Metabolism and Pharmacokinetics of San-Huang-Xie-Xin-Tang, a Polyphenol-Rich Chinese Medicine Formula, in Rats and Ex-Vivo Antioxidant Activity

    Directory of Open Access Journals (Sweden)

    Chi-Sheng Shia

    2011-01-01

    Full Text Available San-Huang-Xie-Xin-Tang (SHXXT, a widely used Chinese herbal formula, consists of rhizomes of Rheum officinale, roots of Scutellaria baicalensis and rhizomes of Coptis chinesis. This study investigated the metabolism and pharmacokinetics of polyphenols in SHXXT, including baicalin, baicalein, wogonin, emodin, aloe-emodin, rhein and chrysophanol. The quantitation methods of SHXXT decoction and rat serum using high performance liquid chromatography were developed and validated in this study. After oral administration of SHXXT decoction to rats, the parent forms of various constituents and their conjugated metabolites in serum were determined before and after hydrolysis with β-glucuronidase and sulfatase. The results showed that only free form of rhein can be quantitated, whereas the parent forms of coptisine, palmatine, berberine, baicalein, wogonin, emodin, aloe-emodin and chrysophanol were not detected in serum. The glucuronides of baicalein, wogonin, emodin, aloe-emodin, rhein and chrysophanol were the predominant forms in bloodstream. In order to evaluate the in vivo antioxidant activity of SHXXT, the serum metabolite of SHXXT was prepared, characterized and followed by evaluation of the effect on AAPH-induced hemolysis. The results indicated that metabolites of SHXXT exhibited significant free radical scavenging activity. We suggest that biologists redirect their focus to the bioactivity of the conjugated metabolites of these polyphenols.

  11. Migration, Displacement, and Movements in the Global Space: Ming-Yuen S. Ma’s Multi-Media Project Xin Lu: A Travelogue in Four Parts

    Directory of Open Access Journals (Sweden)

    Xiaojing Zhou

    2012-06-01

    Full Text Available In her recent work, Sau-ling Cynthia Wong draws critical attention to the implications of the formation of an Asian American “diaporic community” in cyberspace, where race still operates as an organizing principle of power relations. Although cyberspace is not confined by national borders, Wong examines how subversion of and intervention in race- and sex-based hierarchies in cyberspace can articulate Asian American identities in relation to diasporas and the nation-state. This essay explores the politics of artistic invention in diasporas as embedded in the disruption, dislocation, and fragmentation in Ming-Yuen S. Ma’s multi-media project, Xin Lu: A Travelogue in Four Parts—a series of four experimental videos about Chinese diasporas. It argues that by moving outside the nation-space into the experiential and virtual “global space” of diasporas, Ma’s work addresses Wong’s concerns and enacts a viable “virtual mediation” that situates Chinese diasporas in the historical contexts of British colonialism and American racial exploitation and exclusion. This movement also entails confronting other forms of oppression, including sexism and heterosexism in both the East and West. While giving voice and visibility to the struggles of racial and sexual minorities across national borders, Ma demonstrates the possibilities of a historicized critical approach to diasporas, one which underlies Wong’s insistence in critiquing gendered and racialized power structures both within and outside the nation-state.

  12. Kai Xin San aqueous extract improves Aβ1-40-induced cognitive deficits on adaptive behavior learning by enhancing memory-related molecules expression in the hippocampus.

    Science.gov (United States)

    Lu, Cong; Shi, Zhe; Sun, Xiuping; Pan, Ruile; Chen, Shanguang; Li, Yinghui; Qu, Lina; Sun, Lihua; Dang, Haixia; Bu, Lanlan; Chen, Lingling; Liu, Xinmin

    2017-04-06

    Kai Xin San (KXS), a traditional formula of Chinese medicine, has been used to treat dementia. The present study aimed to investigate its ameliorating effects on Aβ 1-40 -induced cognitive impairment in rats using a series of novel reward-directed instrumental learning tasks, and to determine its possible mechanism of action. Rats were pretreated with KXS aqueous extract (0.72 and 1.44g/kg, p.o.) for 10 days, and were trained to gain reward reinforcement by lever pressing at the meantime. Thereafter, rats received a bilateral microinjection of Aβ 1-40 in CA1 regions of the hippocampus. Cognitive performance was evaluated with the goal directed (higher response ratio) and habit (visual signal discrimination and extinction) learning tasks, as well as on the levels of memory-related biochemical parameters and molecules. Our findings first demonstrated that KXS can improve Aβ 1-40 -induced amnesia in RDIL via enhancing the comprehension of action-outcome association and the utilization of cue information to guide behavior. Then, its ameliorating effects should be attributed to the modulation of memory-related molecules in the hippocampus. In conclusion, KXS has the potential to prevent and/or delay the deterioration of cognitive impairment in AD. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  13. Genetics Home Reference: Yao syndrome

    Science.gov (United States)

    ... Oxford). 2014 May;53(5):958-60. doi: 10.1093/rheumatology/ket384. Epub 2013 Nov 19. Citation on ... Oxford). 2015 Oct;54(10):1904-12. doi: 10.1093/rheumatology/kev207. Epub 2015 Jun 11. Citation on ...

  14. Comparatively evaluating the pharmacokinetic of fifteen constituents in normal and blood deficiency rats after oral administration of Xin-Sheng-Hua Granule by UPLC-MS/MS.

    Science.gov (United States)

    Pang, Han-Qing; Tang, Yu-Ping; Cao, Yu-Jie; Tan, Ya-Jie; Jin, Yi; Shi, Xu-Qin; Huang, Sheng-Liang; Sun, Da-Zheng; Sun, Jin; Tang, Zhi-Shu; Duan, Jin-Ao

    2017-09-01

    Xin-Sheng-Hua Granule (XSHG), a famous traditional Chinese medicine prescription, are clinically applied for the treatment of postpartum disease through nourishing blood and promoting blood circulation. In this investigation, a multi-constituents (trigonelline, stachydrine hydrochloride, hydroxysafflor yellow A, chlorogenic acid, amygdalin, leonurine, liquiritin, ferulic acid, senkyunolide I, senkyunolide H, glycyrrhizic acid, senkyunolide A, ligustilide, butylidenephthalide and glycyrrhetinic acid) pharmacokinetic study of XSHG was conducted for the first time. These fifteen constituents in both normal and blood deficiency rat plasma were monitored by using the established and validated ultra-high-performance liquid chromatography coupled with a triple quadrupole electrospray tandem mass spectrometry (UPLC-TQ-MS/MS) method. The samples were prepared through removing protein from plasma with three volumes of methanol. Sufficient separation of target constituents and internal standards (chloramphenicol and clarithromycin) was obtained on a Thermo Scientific Hypersil GOLD column (100mm×3mm, 1.9μm) within a 20min gradient elution (0.1% formic acid aqueous - acetonitrile). Multiple reaction monitoring (MRM) mode was applied to monitor target analytes in both positive and negative electrospray ionization. For the fifteen selected target analytes, this method was fully validated with excellent linearity (r≥0.9925), satisfactory intra- and inter-day precisions (RSD≤11.87%), as well as good accuracies (RE, between -12.84 and 11.69). And the stabilities, matrix effects and extraction recoveries of the rat plasma samples were also within acceptable limits (RSD<15%). Compared to normal group, the pharmacokinetics of major active constituents (except liquiritin and glycyrrhetinic acid) had significant differences (P<0.05) in the model rats, indicated that several metabolite enzymes activities could be altered at disease condition. Copyright © 2017 Elsevier B.V. All

  15. Up-Regulation of CYP2C19 Expression by BuChang NaoXinTong via PXR Activation in HepG2 Cells.

    Directory of Open Access Journals (Sweden)

    Hong Sun

    Full Text Available Cytochrome P450 2C19 (CYP2C19 is an important drug-metabolizing enzyme (DME, which is responsible for the biotransformation of several kinds of drugs such as proton pump inhibitors, platelet aggregation inhibitors and antidepressants. Previous studies showed that Buchang NaoXinTong capsules (NXT increased the CYP2C19 metabolic activity in vitro and enhanced the antiplatelet effect of clopidogrel in vivo. However, the underlying molecular mechanism remained unclear. In the present study, we examined whether Pregnane X receptor (PXR plays a role in NXT-mediated regulation of CYP2C19 expression.We applied luciferase assays, real-time quantitative PCR (qPCR, Western blotting and cell-based analysis of metabolic activity experiments to investigate the NXT regulatory effects on the CYP2C19 promoter activity, the mRNA/ protein expression and the metabolic activity.Our results demonstrated that NXT significantly increased the CYP2C19 promoter activity when co-transfected with PXR in HepG2 cells. Mutations in PXR responsive element abolished the NXT inductive effects on the CYP2C19 promoter transcription. Additionally, NXT incubation (150 and 250μg/mL also markedly up-regulated endogenous CYP2C19 mRNA and protein levels in PXR-transfected HepG2 cells. Correspondingly, NXT leaded to a significant enhancement of the CYP2C19 catalytic activity in PXR-transfected HepG2 cells.In summary, this is the first study to suggest that NXT could induce CYP2C19 expression via PXR activation.

  16. Effects of indium on the intermetallic layer between low-Ag SAC0307-xIn lead-free solders and Cu substrate

    Energy Technology Data Exchange (ETDEWEB)

    Kanlayasiri, Kannachai, E-mail: kkkannac@kmitl.ac.th; Sukpimai, Kamtorn

    2016-05-25

    This research has investigated the effects of indium on the intermetallic layer formation attributable to the reaction between low-Ag SAC0307-xIn lead-free solder and a Cu substrate, where x = 0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 wt%. This study has also examined the post-soldering and post–thermal aging interfacial layers. Morphology parameters were utilized to represent the shape of total intermetallic layer at the interface. The findings indicated that indium had no effect on the pre- and post-aging intermetallic layer overall thicknesses but lowered the Cu{sub 3}Sn/Cu{sub 6}Sn{sub 5} thickness ratio; and that the concentrations of indium exhibited no influence over the post-soldering and post–thermal aging morphology parameter values. In the experiments, the morphology parameter value decreased with increase in the aging time. In addition, the suppression effect of indium on the growth of Cu{sub 3}Sn layer was evident in the post–thermal aging stage with the growth inversely correlated to the indium content. Discussion on the suppression mechanism of indium on the Cu{sub 3}Sn formation is also provided herein. - Highlights: • Indium has no effect on both thickness and morphology of intermetallic layer. • The morphology parameter decreases with the increase of aging time. • Cu{sub 3}Sn/Cu{sub 6}Sn{sub 5} thickness ratio is decreased with the increase of indium content. • Suppression mechanism of indium on the Cu{sub 3}Sn formation is proposed.

  17. Application of Stable Isotope in Hydrologic Analysis of a Rainfall-Runoff Event in the Xin'an Jiang River Basin

    Science.gov (United States)

    Chen, X.; Yi, P.; Chen, L.; Aldahan, A.

    2015-12-01

    Stable isotopes abundance of hydrogen (δ2H) and oxygen (δ18O) are very sensitive to environmental changes and can help understand the complex recharges between surface water and groundwater. However, details of variability in the different components of water supply to watersheds are generally missing. We present here evaluation of isotopic changes in small watershed (0.19 km2) in the upstream of Xin'an River, Anhui province, China based on daily sampling of rainfall events and runoff (river and soil water). The δ2H and δ18O of different water sources in the watershed were aimed in order explore interactions between different parts of the hydrological processes. The collected water samples were analyzed for δ2H and δ18O using Picarro L-2120i analyzer at a precision of 1.0 and 0.1 ‰, respectively. The results indicated higher abundance of 2H and 18O in precipitation than those in river. Additionally, the content of the heavy isotopes also decreases in soil water with depth, while surface soil water was enriched because of evaporation. The response of the watershed to the changes in δ2H and δ18O varied, where water in upstream gained more heavy isotopes rapidly, while in the downstream part the enrichment happened after a few days. This feature suggests a different but still strong hydraulic connection between surface water and groundwater in the small watershed tested here. Accordingly, variability of δ2H and δ18O should be carefully evaluated on a local scale before application in transport system of large rivers and exchange with groundwater.

  18. San-Huang-Xie-Xin-Tang constituents exert drug-drug interaction of mutual reinforcement at both pharmacodynamics and pharmacokinetic level: a review

    Directory of Open Access Journals (Sweden)

    Jiasi Wu

    2016-11-01

    Full Text Available Abstract Inflammatory disorders underlie varieties of human diseases. San-huang-xie-xin-tang (SHXXT, composed with Rhizoma Rhei (Rheum palmatum L., Rhizoma Coptidis (Coptis chinensis Franch, and Radix Scutellaria (Scutellaria baicalensis Georgi, is a famous formula which has been widely used in the fight against inflammatory abnormalities. Mutual reinforcement is one of the basic theories of traditional Chinese medicine. Here this article reviewed and analyzed the recent research on (1 How the main constituents of SHXXT impact on inflammation-associated signaling pathway molecules. (2 The interaction between the main constituents and efflux pumps or intestinal transporters. The goal of this work was to,(1 Provide evidence to support the theory of mutual reinforcement. (2 Clarify the key targets of SHXXT and suggest which targets need further investigation.(3 Give advice for the clinical use of SHXXT to elevated the absorption of main constituents and eventually promote oral bioavailability. We search literatures in scientific databases with key words of ‘each main SHXXT constituent’, in combination with ‘each main inflammatory pathway target molecule’ or each main intestinal transporter, respectively. We report the effect of five main constituents on target molecules which lies in three main inflammatory signaling pathways, we as well investigate the interaction between constituents and intestinal transporter.We conclude,(1The synergistic effect of constituents at both levels confirm the mutual reinforcement theory of TCM as it is proven in this work. (2 The effect of main constituents on downstream targets in nuclear need more further investigation. (3 Drug elevating the absorption of rhein, berberine and baicalein can be employed to promote oral bioavailability of SHXXT.

  19. Comprehensive Identification of Guan-Xin-Shu-Tong Capsule via a Mass Defect and Fragment Filtering Approach by High Resolution Mass Spectrometry: In Vitro and In Vivo Study.

    Science.gov (United States)

    Gao, Xun; Mu, Jingqing; Li, Qing; Guan, Shaoyi; Liu, Ran; Du, Yiyang; Zhang, Huifen; Bi, Kaishun

    2017-06-16

    The Guan-Xin-Shu-Tong capsule (GXSTC) is a well-known traditional Chinese medicine that is used for the treatment of coronary heart disease. Despite its common use in China, basic pharmacological research on its active components is limited. A comprehensive analytical method using quadrupole-time-of-flight mass spectrometry (Q-TOF/MS), specifically with the Triple TOF 5600 platform, was developed to characterize the compounds in the GXSTC powder itself (in vitro) as well as the active components in healthy and heart disease model rats after its oral administration (in vivo). The 5600 platform was operated in both positive and negative ion modes, before the raw data were processed using the extracted ion chromatography (EIC), mass defect filtering (MDF) and fragment filtering (FF) techniques. With the aid of reference compounds for retention time and fragment ion comparisons, 18 compounds were unambiguously identified in vitro. An additional 56 other compounds were tentatively characterized using the accurate quasi-molecular ion mass and Tandem mass spectrometry (MS/MS) fragmentation pattern strategies. Among them, 30 compounds were characterized based on the MDF and FF approaches. Normal rats in addition to hyperlipidemic (HL) and acute blood stasis (ABS) model rats were given a single oral dose of GXSTC solution for subsequent blood analysis at 1 and 2 h after administration. A total of 24 prototypecomponents and 20 metabolites derived from GXSTC were differentially detected across the three animal groups, including the absence of four phase II phenolic acid metabolites in the ABS group and the presence of three diterpenoid-related metabolites exclusive to the HL group. The use of reference compounds as well as the mass defect and fragment-filtering strategies were critical to identify GXSTC compounds in vitro and in vivo. This can be used for further quality control and pharmacological studies aimed at characterizing the active and potential beneficial compounds

  20. Electrophysiological effects of Chinese medicine Shen song Yang xin (SSYX) on Chinese miniature swine heart and isolated guinea pig ventricular myocytes.

    Science.gov (United States)

    Feng, Li; Gong, Jing; Jin, Zhen-yi; Li, Ning; Sun, Li-ping; Wu, Yi-ling; Pu, Jie-lin

    2009-07-05

    Shen song Yang xin (SSYX) is a compound of Chinese medicine with the effect of increasing heart rate (HR). This study aimed to evaluate its electrophysiological properties at heart and cellular levels. The Chinese miniature swines were randomly assigned to two groups, administered with SSYX or placebo for 4 weeks (n = 8 per group). Cardiac electrophysiological study (EPS) was performed before and after drug administration. The guinea pig ventricular myocytes were enzymatically isolated and whole cell voltage-clamp technique was used to evaluate the effect of SSYX on cardiac action potential (AP). SSYX treatment accelerated the HR from (141.8 +/- 36.0) beats per minute to (163.0 +/- 38.0) beats per minute (P = 0.013) without changing the other parameters in surface electrocardiogram. After blockage of the autonomic nervous system with metoprolol and atropin, SSYX had no effect on intrinsic HR (IHR), but decreased corrected sinus node recovery time (CSNRT) and sinus atrium conducting time (SACT). Intra cardiac EPS showed that SSYX significantly decreased the A-H and A-V intervals as well as shortened the atrial (A), atrioventricular node (AVN) and ventricular (V) effective refractory period (ERP). In isolated guinea pig ventricular myocytes, the most obvious effect of SSYX on action potential was a shortening of the action potential duration (APD) without change in shape of action potential. The shortening rates of APD(30), APD(50) and APD(90) were 19.5%, 17.8% and 15.3%, respectively. The resting potential (Em) and the interval between the end of APD(30) and APD(90) did not significantly change. The present study demonstrates that SSYX increases the HR and enhances the conducting capacity of the heart in the condition of the intact autonomic nervous system. SSYX homogenously decreases the ERP of the heart and shortens the APD of the myocytes, suggesting its antiarrhythmic effect without proarrhythmia.

  1. Bu-Shen-Ning-Xin Decoction ameliorated the osteoporotic phenotype of ovariectomized mice without affecting the serum estrogen concentration or uterus

    Directory of Open Access Journals (Sweden)

    Wang L

    2015-08-01

    Full Text Available Ling Wang,1,2,* Xue-Min Qiu,1,2,* Yu-Yan Gui,1,2 Ying-Ping Xu,1,2 Hans-Jürgen Gober,3 Da-Jin Li1 1Laboratory for Reproductive Immunology, Hospital and Institute of Obstetrics and Gynecology, IBS, Fudan University Shanghai Medical College, 2Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, People’s Republic of China; 3Department of Pharmacy, Wagner Jauregg Hospital and Children’s Hospital, Linz, Austria *These authors contributed equally to this work Introduction: Bu-Shen-Ning-Xin Decoction (BSNXD, a traditional Chinese medicinal composition, has been used as a remedy for postmenopausal osteoporosis, but its effects on bone metabolism and the uterus have not been reported.Purpose: We aimed to determine the respective effects of BSNXD on the bones and the uterus of ovariectomized (OVX mice to evaluate the efficacy and safety of this herbal formula.Materials and methods: Postmenopausal osteoporosis animal models that were generated by ovariectomy were treated with BSNXD. Dual-energy X-ray absorptiometry was performed to analyze the bone mineral density, and histomorphometric analysis was performed to measure the parameters related to bone metabolism. Calcein labeling was performed to detect bone formation. The uteruses from the mice were weighed, and the histomorphometry was analyzed. Drug-derived serum was prepared to assess the 17-β-estradiol concentration via enzyme immunoassay.Results: BSNXD administration ameliorated the osteoporotic phenotype of OVX mice, as evidenced by an increase in the bone mineral density and bone volume; these effects could not be abolished by the administration of the aromatase inhibitor letrozole. Moreover, BSNXD had no effect on the serum estrogen concentration or uterus.Conclusion: These results suggest that BSNXD has ameliorating effects on bone loss due to estrogen deprivation without affecting the peripheral blood estrogen concentration or the uterus in OVX mice. Keywords

  2. A novel family of RGD-containing disintegrin (Tablysin-15) from the salivary gland of the horsefly Tabanus yao targets integrins αIIbβ3 and αVβ3 and inhibits platelet aggregation and angiogenesis

    Science.gov (United States)

    Ma, Dongying; Xu, Xueqing; An, Su; Liu, Huan; Yang, Xuening; Andersen, John F.; Wang, Yipeng; Tokumasu, Fuyuki; Ribeiro, José M. C.; Francischetti, Ivo M. B.; Lai, Ren

    2012-01-01

    A novel family of RGD-containing molecule (Tablysin-15) has been molecularly characterized from the salivary gland of the hematophagous horsefly Tabanus yao. Tablysin-15 does not share primary sequence homology to any disintegrin discovered so far, and displays an RGD motif in the N-terminus of the molecule. It is also distinct from disintegrins from Viperidae since its mature form is not released from a metalloproteinase precursor. Tablysin-15 exhibits high affinity for platelet αIIbβ3 and endothelial cell αvβ3 integrins, but not for α5β1 or α2β1. Accordingly, it blocks endothelial cell adhesion to vitronectin (IC50 ~ 1 nM) and marginally to fibronectin (IC50 ~ 1 µM), but not to collagen. It also inhibits FGF-induced endothelial cell proliferation, and attenuates tube formation in vitro. In platelets, Tablysin-15 inhibits aggregation induced by collagen, ADP and convulxin, and prevents static platelet adhesion to immobilized fibrinogen. In addition, solid-phase assays and flow cytometry demonstrates that αIIbβ3 binds to Tablysin-15. Moreover, immobilized Tablysin-15 supports platelet adhesion by a mechanism which was blocked by anti-integrin αIIbβ3 monoclonal antibody (e.g. abciximab) or by EDTA. Furthermore, Tablysin-15 dose-dependently attenuates thrombus formation to collagen under flow, without affecting platelet adhesion to collagen fibrils. Consistent with these findings, Tablysin-15 displays antithrombotic properties in vivo suggesting that it is a useful tool to block αIIbβ3, or as a prototype to develop antithrombotics. The RGD motif in the unique sequence of Tablysin-15 represents a novel template for studying the structure-function relationship of the disintegrin family of inhibitors. PMID:21475772

  3. Magnetic properties and magnetocaloric effect in the HoNi{sub 1−x}Cu{sub x}In (x=0, 0.1, 0.3, 0.4) intermetallic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Mo, Zhao-Jun [School of Material Science and Engineering, Hebei University of Technology, Tianjin (China); Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing (China); Shen, Jun, E-mail: jshen@mail.ipc.ac.cn [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing (China); Yan, Li-Qin [State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter, Physics and Institute of Physics, Chinese Academy of Sciences, Beijing (China); Tang, Cheng-Chun [School of Material Science and Engineering, Hebei University of Technology, Tianjin (China); He, Xiao-Nan [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing (China); Zheng, Xinqi [State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter, Physics and Institute of Physics, Chinese Academy of Sciences, Beijing (China); Wu, Jian-Feng [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing (China); Sun, Ji-Rong; Shen, Bao-Gen [State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter, Physics and Institute of Physics, Chinese Academy of Sciences, Beijing (China)

    2014-03-15

    The magnetic properties and magnetocaloric effect (MCE) in HoNi{sub 1−x}Cu{sub x}In (x=0, 0.1, 0.3, 0.4) compounds have been investigated. With the substitution of Cu for Ni, the Ho magnetic moment will cant from the c-axis, and form a complicated magnetic structure. These compounds exhibit two successive magnetic transitions with the increase in temperature. The large reversible magnetocaloric effects have been observed in HoNi{sub 1−x}Cu{sub x}In compounds around T{sub ord}, with no thermal and magnetic hysteresis loss. The large reversible isothermal magnetic entropy change (−ΔS{sub M}) is 20.2 J/kg K and the refrigeration capacity (RC) reaches 356.7 J/kg for field changes of 5 T for HoNi{sub 0.7}Cu{sub 0.3}In. Especially, the value of −ΔS{sub M} (12.5 J/kg K) and the large RC (132 J/kg) are observed for field changes of 2 T for HoNi{sub 0.9}Cu{sub 0.1}In. Additionally, the values of RC are improved to 149 J/K for the field changes of 2 T due to a wide temperature span for the mix of HoNi{sub 0.9}Cu{sub 0.1}In and HoNi{sub 0.7}Cu{sub 0.3}In compounds with the mass ratio of 1:1. These compounds with excellent MCE are expected to have effective applications in magnetic refrigeration around 20 K. - Highlights: • For magnetic-field changes of 2 T, the values of RC are improved to 149 J/K. • MCEs of these compounds show no thermal and magnetic hysteresis. • Compounds show two successive magnetic transitions with the increase in temperature. • With the substitution of Cu for Ni, compounds form a complicated magnetic structure.

  4. Protective effect of Xin Mai Jia ultrafiltration extract on human umbilical vein endothelial cell injury induced by hydrogen peroxide and the effect on the NO-cGMP signaling pathway

    Science.gov (United States)

    YIN, YALING; WAN, JIA; LI, PENG; JIA, YANLONG; SUN, RUILI; PAN, GUOPIN; WAN, GUANGRUI

    2014-01-01

    The aim of the present study was to evaluate the protective effect of the ultrafiltration extract of Xin Mai Jia (XMJ) on a human umbilical vein endothelial cell (HUVEC) injury model induced by hydrogen peroxide (H2O2), by providing experimental data to investigate the mechanism and efficacy underlying the therapeutic effects on atherosclerosis. HUVECs were first injured by H2O2 and then varying final concentrations of the Chinese herb extract were added. Effects of the XMJ extract on morphology, activity, monolayer permeability, biochemical indicators, cytokines, endothelial nitric oxide synthase (eNOS) protein content and eNOS gene expression in the HUVECs were analyzed. H2O2 significantly promoted HUVEC injury. The XMJ ultrafiltration extract significantly improved the morphological changes in the injured HUVECs. In addition, XMJ treatment increased cell activity and decreased monolayer permeability. The expression levels of intracellular adhesion molecule-1, vascular adhesion molecule-1, interleukin-1 and -6 and nuclear factor-κB decreased, while the expression levels of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 increased with XMJ administration. Increased levels of nitric oxide (NO), eNOS protein and eNOS gene expression were also observed. Therefore, the XMJ ultrafiltration extract exhibits marked anti-inflammatory effects and antioxidant abilities. These properties significantly inhibited the H2O2-induced injury of HUVECs, which may be associated with the NO-cyclic guanosine monophosphate signaling pathway. PMID:24944594

  5. 1528-IJBCS-Article-Yao Kouakou

    African Journals Online (AJOL)

    hp

    Cette étude a évalué les performances zootechniques des hybrides F2 issus du croisement intergénérique entre Oreochromis niloticus et Sarotherodon melanotheron et comparé à celles des parents en élevage en milieu lagunaire. Des essais de pré grossissement en élevage monosexe mâle et femelle ont été réalisés ...

  6. 1881-IJBCS-Article-Yao Woegan

    African Journals Online (AJOL)

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    Aubrevillea kerstingii (A6), à Pentadesma butyracea (A5), à Dacryodes klaineana et. Parinari glabra (C4), à Dialium guineense et. Cola millenii (C1), à Anogeissus leiocarpus et Margaritaria dioscoidea (C2) et à Khaya senegalensis (C3). Dans les forêts claires, sont identifiés les groupements à Isoberlinia doka (B2) et à.

  7. 2483-IJBCS-Article-Dr Akpo Yao

    African Journals Online (AJOL)

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    demande sur le marché national est aujourd'hui en forte .... Analyse statistique. Le test bilatéral de Z du logiciel SAS. (Statistical Analysis System, 2010) était utilisé pour la comparaison des différents pourcentages. Un seuil de significativité de ... avaient évoqué les risques liés au caractère vivant du vaccin. Enfin, en matière.

  8. 1758-IJBCS-Article-Hoekou Yao

    African Journals Online (AJOL)

    hp

    Les activités antifongiques des extraits de Cassia alata L. et de Piliostigma thonningii (Schumach.) Milne Redh. ont été évaluées sur Candida albicans par la méthode de dilution en milieu liquide couplée à l'étalement sur milieu gélosé. Les résultats obtenus montrent que C. albicans est totalement inhibé par l'extrait.

  9. 341-IJBCS-Article-Yao Koffi Marcelin

    African Journals Online (AJOL)

    Dr Gatsing

    2 Laboratoire de Chimie Physique, Université de Cocody, 22 BP 582 Abidjan 22, Côte d'Ivoire. 2 Laboratoire de Chimie Physique, Université de Cocody, 22 BP 582 Abidjan 22, Côte ...... apports de solides en suspension par les eaux de ruissellement et les effluents domestiques industriels est maximale ; mais il semble ...

  10. 1809-IJBCS-Article-Hoekou Yao

    African Journals Online (AJOL)

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    Cette étude s'est appuyée sur des données d'enquêtes ethnobotaniques effectuées dans la. Région centrale du Togo dans un contexte de valorisation de la flore médicinale. L'étude a permis de ressortir la fréquente utilisation de Pterocarpus erinaceus et Daniella oliveri, dans le traitement de maladies infectieuses.

  11. 1420-IJBCS-Article-Theodore K. Yao

    African Journals Online (AJOL)

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    les conséquences de la pollution au nitrate et son corollaire. MATÉRIEL ET MÉTHODES. Cadre d'étude. Le domaine d'étude d'une superficie d'environ 8 590 km2, est ...... d'ordures, d'eaux stagnantes et verdâtres, etc. En outre, le vieillissement de certains ouvrages amène à penser que les équipements installés pour les ...

  12. 70994-179427-Yao et al- +DOI

    African Journals Online (AJOL)

    confo

    Résumé. Pour mieux comprendre la survenue de certaines anomalies chez des patients alcooliques chroniques, la recherche d'éventuelles relations entre les anomalies induites par l'alcoolisme chronique et le type d'alcools consommés, a été réalisée. 307 dossiers d'alcooliques chroniques ont été sélectionnés en ...

  13. 2367-IJBCS-Article-Koffi Mathias Yao

    African Journals Online (AJOL)

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    En vue d'estimer les consommations excessives d'alcool (binge drinking) en Côte d'Ivoire, une enquête mettant en parallèle les types ... et les employés subalternes (43,4%) sont plus touchés par ce phénomène de binge drinking. Par ailleurs, avec ...... students in 35 European countries. Stockholm, Swedish Council for.

  14. 2168-IJBCS-Article-Yao Brou

    African Journals Online (AJOL)

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    mg/kg de zinc dans l'Armillaria mellea, un champignon comestible. Evaluation du niveau de contamination des champignons. Les teneurs métalliques moyennes de toutes les espèces de champignon sont inférieures aux limites maximales de résidus. (LMR) du plomb (0,3 mg/kg) et du cadmium. (0,2 mg/kg), fixées par ...

  15. 2483-IJBCS-Article-Dr Akpo Yao

    African Journals Online (AJOL)

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    1Faculté d'Agronomie de l'Université de Parakou, Laboratoire d'Ecologie, de Santé et de Productions. Animales (LESPA), BP 123 Parakou, Bénin. 2Ecole Polytechnique d'Abomey-Calavi - Laboratoire de Recherche en Biologie Appliquée (LARBA),. Unité de Recherche Cunicole et Cavicole (URCC), 01 BP 2009 Cotonou, ...

  16. 2140-IJBCS-Article-Koffi Marcelin Yao

    African Journals Online (AJOL)

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    les pays développés et émergents. Les métaux lourds sont des éléments métalliques dont la densité est supérieure à 5 (Duffus, 2002). Ces métaux ne sont pas biodégradables et persistent donc dans l'environnement pendant de longues périodes (Morin et al., 2008;. Bonanno and Giudice, 2010; Baralkiewick et al., 2010).

  17. 1881-IJBCS-Article-Yao Woegan

    African Journals Online (AJOL)

    hp

    L'Atakora, ensemble tectonisé et plissé, marqué par un épiderme quartzitique ;. - Le Dahoméen, ancien plateau enrasé par l'érosion différentielle, formé de roches métamorphiques (micaschistes et gneiss). Le climat est de type tropical humide en altitude et soudanien dans les plaines à saison pluvieuse d'avril à octobre et ...

  18. 1001-IJBCS-Article- Prof Akpo Yao

    African Journals Online (AJOL)

    DR GATSING

    de Eimeria media issues du Bénin en vue de leur utilisation comme souches vaccinales. Y. AKPO 1*, M. T. ..... 1970. Coccidiosis of rabbits at. Ondersterpoort. J. S. Afr. Vet. Ass., 41: 189-194. Drouet-Viard F, Coudert P, Licois D, Boivin. M. 1995. Vaccination of rabbits against coccidiosis with precocious Eimeria lines. Vet.

  19. 1758-IJBCS-Article-Hoekou Yao

    African Journals Online (AJOL)

    hp

    laboratoires qui se tournent vers les plantes pour la recherche des composés actifs. (Pousset, 2006). Cet intérêt particulier est motivé par la résistance permanente de certains germes aux antibiotiques classiques qui suscite la recherche de nouveaux principes actifs à base de plantes comme sources de composés pour ...

  20. Optoelectronic properties of XIn{sub 2}S{sub 4} (X = Cd, Mg) thiospinels through highly accurate all-electron FP-LAPW method coupled with modified approximations

    Energy Technology Data Exchange (ETDEWEB)

    Yousaf, Masood [Department of Physics, Ulsan National Institute of Science and Technology, Ulsan 689-798 (Korea, Republic of); Physics Department, Faculty of Science, Universiti Teknologi Malaysia, Skudai 81310, Johor (Malaysia); Dalhatu, S.A. [Physics Department, Faculty of Science, Universiti Teknologi Malaysia, Skudai 81310, Johor (Malaysia); Murtaza, G. [Department of Physics, Islamia College, Peshawar, KPK (Pakistan); Khenata, R. [Laboratoire de Physique Quantique et de Modélisation Mathématique (LPQ3M), Département de Technologie, Université de Mascara, 29000 Mascara (Algeria); Sajjad, M. [School of Electronic Engineering, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Musa, A. [Physics Department, Faculty of Science, Universiti Teknologi Malaysia, Skudai 81310, Johor (Malaysia); Rahnamaye Aliabad, H.A. [Department of Physics, Hakim Sabzevari University (Iran, Islamic Republic of); Saeed, M.A., E-mail: saeed@utm.my [Physics Department, Faculty of Science, Universiti Teknologi Malaysia, Skudai 81310, Johor (Malaysia)

    2015-03-15

    Highlights: • Highly accurate all-electron FP-LAPW+lo method is used. • New physical parameters are reported, important for the fabrication of optoelectronic devices. • A comparative study that involves FP-LAPW+lo method and modified approximations. • Computed band gap values have good agreement with the experimental values. • Optoelectronic results of fundamental importance can be utilized for the fabrication of devices. - Abstract: We report the structural, electronic and optical properties of the thiospinels XIn{sub 2}S{sub 4} (X = Cd, Mg), using highly accurate all-electron full potential linearized augmented plane wave plus local orbital method. In order to calculate the exchange and correlation energies, the method is coupled with modified techniques such as GGA+U and mBJ-GGA, which yield improved results as compared to the previous studies. GGA+SOC approximation is also used for the first time on these compounds to examine the spin orbit coupling effect on the band structure. From the analysis of the structural parameters, robust character is predicted for both materials. Energy band structures profiles are fairly the same for GGA, GGA+SOC, GGA+U and mBJ-GGA, confirming the indirect and direct band gap nature of CdIn{sub 2}S{sub 4} and MgIn{sub 2}S{sub 4} materials, respectively. We report the trend of band gap results as: (mBJ-GGA) > (GGA+U) > (GGA) > (GGA+SOC). Localized regions appearing in the valence bands for CdIn{sub 2}S{sub 4} tend to split up nearly by ≈1 eV in the case of GGA+SOC. Many new physical parameters are reported that can be important for the fabrication of optoelectronic devices. Optical spectra namely, dielectric function (DF), refractive index n(ω), extinction coefficient k(ω), reflectivity R(ω), optical conductivity σ(ω), absorption coefficient α(ω) and electron loss function are discussed. Optical’s absorption edge is noted to be 1.401 and 1.782 for CdIn{sub 2}S{sub 4} and MgIn{sub 2}S{sub 4}, respectively. The

  1. Bu-Shen-Ning-Xin decoction: inhibition of osteoclastogenesis by abrogation of the RANKL-induced NFATc1 and NF-κB signaling pathways via selective estrogen receptor α

    Directory of Open Access Journals (Sweden)

    Wang L

    2015-07-01

    Full Text Available Ling Wang,1,2,* Xue-Min Qiu,1,2,* Yu-Yan Gui,1,2 Ying-Ping Xu,1,2 Hans-Jürgen Gober,3 Da-Jin Li11Laboratory for Reproductive Immunology, Hospital and Institute of Obstetrics and Gynecology, IBS, Fudan University Shanghai Medical College, 2Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, People’s Republic of China; 3Department of Pharmacy, Wagner Jauregg Hospital and Children’s Hospital, Wagner Jauregg Weg, Linz, Austria*These authors contributed equally to this workIntroduction: Bu-Shen-Ning-Xin decoction (BSNXD is a traditional Chinese medicinal composition that has been used as a remedy for postmenopausal osteoporosis, but the mechanisms affecting bone metabolism are not fully understood.Purpose: We investigated the molecular mechanism and signaling pathway underlying the effect of BSNXD on osteoclastogenesis.Materials and methods: A postmenopausal osteoporosis animal model generated by ovariectomy was administered BSNXD and drug-derived serum was prepared. An enzyme immunoassay was conducted to measure the 17-β-estradiol (E2 concentration in the drug-derived serum. Bone marrow-derived monocyte/macrophage precursor cells were treated with drug-derived serum, and tartrate-resistance acid phosphatase staining was conducted to observe osteoclastogenesis. A bone resorption assay was performed to analyze the effect on osteoclastic resorptive function. Real-time PCR, flow cytometry, Western blotting, transfection, and luciferase assays were conducted to explore the related mechanism.Results: E2 was not elevated in BSNXD-derived serum. BSNXD-derived serum suppressed receptor activation of nuclear factor κB ligand (RANKL-activated osteoclastogenesis in a dose-dependent manner; this effect could be reversed by estrogen receptor α antagonist methyl-piperidino-pyrazole. The serum suppressed RANKL-induced NF-κB transcription and inhibited the accumulation of nuclear factor of activated T-cells, cytoplasmic 1

  2. From Wireless Sensor Networks to Wireless Body Area Networks: Formal Modeling and Verification on Security Using PAT

    Directory of Open Access Journals (Sweden)

    Tieming Chen

    2016-01-01

    Full Text Available Model checking has successfully been applied on verification of security protocols, but the modeling process is always tedious and proficient knowledge of formal method is also needed although the final verification could be automatic depending on specific tools. At the same time, due to the appearance of novel kind of networks, such as wireless sensor networks (WSN and wireless body area networks (WBAN, formal modeling and verification for these domain-specific systems are quite challenging. In this paper, a specific and novel formal modeling and verification method is proposed and implemented using an expandable tool called PAT to do WSN-specific security verification. At first, an abstract modeling data structure for CSP#, which is built in PAT, is developed to support the node mobility related specification for modeling location-based node activity. Then, the traditional Dolev-Yao model is redefined to facilitate modeling of location-specific attack behaviors on security mechanism. A throughout formal verification application on a location-based security protocol in WSN is described in detail to show the usability and effectiveness of the proposed methodology. Furthermore, also a novel location-based authentication security protocol in WBAN can be successfully modeled and verified directly using our method, which is, to the best of our knowledge, the first effort on employing model checking for automatic analysis of authentication protocol for WBAN.

  3. In vitro evidence of possible influence of scutellarein towards bile ...

    African Journals Online (AJOL)

    In vitro evidence of possible influence of scutellarein towards bile acids' metabolism. Z Shu-Yao, J Hong, L Chao-Xian, Z Zhi-Wei, D Xin, C Lei. Abstract. Background: The glucuronidation process has been regarded as the key elimination process for toxic bile acids. UDPglucuronosyltransferase (UGT) 1A3 is one important ...

  4. Learning Networks, Networked Learning

    NARCIS (Netherlands)

    Sloep, Peter; Berlanga, Adriana

    2010-01-01

    Sloep, P. B., & Berlanga, A. J. (2011). Learning Networks, Networked Learning [Redes de Aprendizaje, Aprendizaje en Red]. Comunicar, XIX(37), 55-63. Retrieved from http://dx.doi.org/10.3916/C37-2011-02-05

  5. A network of networks.

    Science.gov (United States)

    Iedema, Rick; Verma, Raj; Wutzke, Sonia; Lyons, Nigel; McCaughan, Brian

    2017-04-10

    Purpose To further our insight into the role of networks in health system reform, the purpose of this paper is to investigate how one agency, the NSW Agency for Clinical Innovation (ACI), and the multiple networks and enabling resources that it encompasses, govern, manage and extend the potential of networks for healthcare practice improvement. Design/methodology/approach This is a case study investigation which took place over ten months through the first author's participation in network activities and discussions with the agency's staff about their main objectives, challenges and achievements, and with selected services around the state of New South Wales to understand the agency's implementation and large system transformation activities. Findings The paper demonstrates that ACI accommodates multiple networks whose oversight structures, self-organisation and systems change approaches combined in dynamic ways, effectively yield a diversity of network governances. Further, ACI bears out a paradox of "centralised decentralisation", co-locating agents of innovation with networks of implementation and evaluation expertise. This arrangement strengthens and legitimates the role of the strategic hybrid - the healthcare professional in pursuit of change and improvement, and enhances their influence and impact on the wider system. Research limitations/implications While focussing the case study on one agency only, this study is unique as it highlights inter-network connections. Contributing to the literature on network governance, this paper identifies ACI as a "network of networks" through which resources, expectations and stakeholder dynamics are dynamically and flexibly mediated and enhanced. Practical implications The co-location of and dynamic interaction among clinical networks may create synergies among networks, nurture "strategic hybrids", and enhance the impact of network activities on health system reform. Social implications Network governance requires more

  6. Declarative Networking

    CERN Document Server

    Loo, Boon Thau

    2012-01-01

    Declarative Networking is a programming methodology that enables developers to concisely specify network protocols and services, which are directly compiled to a dataflow framework that executes the specifications. Declarative networking proposes the use of a declarative query language for specifying and implementing network protocols, and employs a dataflow framework at runtime for communication and maintenance of network state. The primary goal of declarative networking is to greatly simplify the process of specifying, implementing, deploying and evolving a network design. In addition, decla

  7. The network researchers' network

    DEFF Research Database (Denmark)

    Henneberg, Stephan C.; Jiang, Zhizhong; Naudé, Peter

    2009-01-01

    The Industrial Marketing and Purchasing (IMP) Group is a network of academic researchers working in the area of business-to-business marketing. The group meets every year to discuss and exchange ideas, with a conference having been held every year since 1984 (there was no meeting in 1987). In thi......The Industrial Marketing and Purchasing (IMP) Group is a network of academic researchers working in the area of business-to-business marketing. The group meets every year to discuss and exchange ideas, with a conference having been held every year since 1984 (there was no meeting in 1987......). In this paper, based upon the papers presented at the 22 conferences held to date, we undertake a Social Network Analysis in order to examine the degree of co-publishing that has taken place between this group of researchers. We identify the different components in this database, and examine the large main...

  8. Network cosmology.

    Science.gov (United States)

    Krioukov, Dmitri; Kitsak, Maksim; Sinkovits, Robert S; Rideout, David; Meyer, David; Boguñá, Marián

    2012-01-01

    Prediction and control of the dynamics of complex networks is a central problem in network science. Structural and dynamical similarities of different real networks suggest that some universal laws might accurately describe the dynamics of these networks, albeit the nature and common origin of such laws remain elusive. Here we show that the causal network representing the large-scale structure of spacetime in our accelerating universe is a power-law graph with strong clustering, similar to many complex networks such as the Internet, social, or biological networks. We prove that this structural similarity is a consequence of the asymptotic equivalence between the large-scale growth dynamics of complex networks and causal networks. This equivalence suggests that unexpectedly similar laws govern the dynamics of complex networks and spacetime in the universe, with implications to network science and cosmology.

  9. Network Cosmology

    Science.gov (United States)

    Krioukov, Dmitri; Kitsak, Maksim; Sinkovits, Robert S.; Rideout, David; Meyer, David; Boguñá, Marián

    2012-01-01

    Prediction and control of the dynamics of complex networks is a central problem in network science. Structural and dynamical similarities of different real networks suggest that some universal laws might accurately describe the dynamics of these networks, albeit the nature and common origin of such laws remain elusive. Here we show that the causal network representing the large-scale structure of spacetime in our accelerating universe is a power-law graph with strong clustering, similar to many complex networks such as the Internet, social, or biological networks. We prove that this structural similarity is a consequence of the asymptotic equivalence between the large-scale growth dynamics of complex networks and causal networks. This equivalence suggests that unexpectedly similar laws govern the dynamics of complex networks and spacetime in the universe, with implications to network science and cosmology. PMID:23162688

  10. Telecommunication networks

    CERN Document Server

    Iannone, Eugenio

    2011-01-01

    Many argue that telecommunications network infrastructure is the most impressive and important technology ever developed. Analyzing the telecom market's constantly evolving trends, research directions, infrastructure, and vital needs, Telecommunication Networks responds with revolutionized engineering strategies to optimize network construction. Omnipresent in society, telecom networks integrate a wide range of technologies. These include quantum field theory for the study of optical amplifiers, software architectures for network control, abstract algebra required to design error correction co

  11. C:\\Users\\AISA\\Desktop\\G. ACAPOVI-YAO.xps

    African Journals Online (AJOL)

    AISA

    (une petite de juillet à Août, une grande de. Novembre à Mars). La température oscille entre. 25 et 33°C avec une forte pluviométrie de plus de. 1500 mm de pluie par an. Ces dernières années, il est noté un bouleversement dans la répartition des pluies et donc des saisons, consécutifs au réchauffement climatique de la ...

  12. 2547-IJBCS-Article-Dr Koffi Marcelin yao

    African Journals Online (AJOL)

    hp

    The impact of pesticides on environmental quality is of great concern in many developing countries. However, data on pesticide contamination levels in African estuaries has mainly focused on organochlorine compounds, although some among other pesticide families are able to persist in water for several days and pose ...

  13. 2547-IJBCS-Article-Dr Koffi Marcelin yao

    African Journals Online (AJOL)

    hp

    et crimidine ont été examinées dans les eaux et les sédiments autour de la décharge municipale d'Akouédo. (Côte d'Ivoire). ... sédiments par l'aldicarbe et la crimidine à des fréquences de détection très élevées, contrairement aux eaux lagunaires et ..... certains invertébrés en milieu marin et qu'une concentration de 1500 ...

  14. 1016-IJBCS-Article-Dr Koffi Mathias Yao

    African Journals Online (AJOL)

    DR GATSING

    le vieillissement de ces plantations ont contribué à l'utilisation préférentielle du vin de palme pour la production du Koutoukou. Dans une étude réalisée par Camara ..... montre que les modifications hormonales engendrées par le cycle menstruel, ne permettent pas de tirer des conclusions efficaces en cas de comparaisons.

  15. Interconnected networks

    CERN Document Server

    2016-01-01

    This volume provides an introduction to and overview of the emerging field of interconnected networks which include multi layer or multiplex networks, as well as networks of networks. Such networks present structural and dynamical features quite different from those observed in isolated networks. The presence of links between different networks or layers of a network typically alters the way such interconnected networks behave – understanding the role of interconnecting links is therefore a crucial step towards a more accurate description of real-world systems. While examples of such dissimilar properties are becoming more abundant – for example regarding diffusion, robustness and competition – the root of such differences remains to be elucidated. Each chapter in this topical collection is self-contained and can be read on its own, thus making it also suitable as reference for experienced researchers wishing to focus on a particular topic.

  16. Network maintenance

    CERN Multimedia

    IT Department

    2009-01-01

    A site wide network maintenance has been scheduled for Saturday 28 February. Most of the network devices of the General Purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites along this day. This upgrade will not affect: the Computer centre itself, building 613, the Technical Network and the LHC experiments dedicated networks at the pits. Should you need more details on this intervention, please contact Netops by phone 74927 or email mailto:Netops@cern.ch. IT/CS Group

  17. Network maintenance

    CERN Multimedia

    GS Department

    2009-01-01

    A site-wide network maintenance operation has been scheduled for Saturday 28 February. Most of the network devices of the general purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites throughout the day. This upgrade will not affect the Computer Centre itself, Building 613, the Technical Network and the LHC experiments, dedicated networks at the pits. For further details of this intervention, please contact Netops by phone 74927 or e-mail mailto:Netops@cern.ch. IT/CS Group

  18. Network Ambivalence

    Directory of Open Access Journals (Sweden)

    Patrick Jagoda

    2015-08-01

    Full Text Available The language of networks now describes everything from the Internet to the economy to terrorist organizations. In distinction to a common view of networks as a universal, originary, or necessary form that promises to explain everything from neural structures to online traffic, this essay emphasizes the contingency of the network imaginary. Network form, in its role as our current cultural dominant, makes scarcely imaginable the possibility of an alternative or an outside uninflected by networks. If so many things and relationships are figured as networks, however, then what is not a network? If a network points towards particular logics and qualities of relation in our historical present, what others might we envision in the future? In  many ways, these questions are unanswerable from within the contemporary moment. Instead of seeking an avant-garde approach (to move beyond networks or opting out of networks (in some cases, to recover elements of pre-networked existence, this essay proposes a third orientation: one of ambivalence that operates as a mode of extreme presence. I propose the concept of "network aesthetics," which can be tracked across artistic media and cultural forms, as a model, style, and pedagogy for approaching interconnection in the twenty-first century. The following essay is excerpted from Network Ambivalence (Forthcoming from University of Chicago Press. 

  19. Network neuroscience.

    Science.gov (United States)

    Bassett, Danielle S; Sporns, Olaf

    2017-02-23

    Despite substantial recent progress, our understanding of the principles and mechanisms underlying complex brain function and cognition remains incomplete. Network neuroscience proposes to tackle these enduring challenges. Approaching brain structure and function from an explicitly integrative perspective, network neuroscience pursues new ways to map, record, analyze and model the elements and interactions of neurobiological systems. Two parallel trends drive the approach: the availability of new empirical tools to create comprehensive maps and record dynamic patterns among molecules, neurons, brain areas and social systems; and the theoretical framework and computational tools of modern network science. The convergence of empirical and computational advances opens new frontiers of scientific inquiry, including network dynamics, manipulation and control of brain networks, and integration of network processes across spatiotemporal domains. We review emerging trends in network neuroscience and attempt to chart a path toward a better understanding of the brain as a multiscale networked system.

  20. Organizational Networks

    DEFF Research Database (Denmark)

    Grande, Bård; Sørensen, Ole Henning

    1998-01-01

    The paper focuses on the concept of organizational networks. Four different uses of the concept of organizational network are identified and critically discussed. Special focus is placed on how information and communication technologies as communication mediators and cognitive pictures influence...

  1. Network workshop

    DEFF Research Database (Denmark)

    Bruun, Jesper; Evans, Robert Harry

    2014-01-01

    This paper describes the background for, realisation of and author reflections on a network workshop held at ESERA2013. As a new research area in science education, networks offer a unique opportunity to visualise and find patterns and relationships in complicated social or academic network data...... research community. With this workshop, participants were offered a way into network science based on authentic educational research data. The workshop was constructed as an inquiry lesson with emphasis on user autonomy. Learning activities had participants choose to work with one of two cases of networks...... network methodology in one’s research might supersede the perceived benefits of doing so. As a response to that problem, we argue that workshops can act as a road towards meaningful engagement with networks and highlight that network methodology promises new ways of interpreting data to answer questions...

  2. Social Networks

    OpenAIRE

    Martí, Joan; Zenou, Yves

    2009-01-01

    We survey the literature on social networks by putting together the economics, sociological and physics/applied mathematics approaches, showing their similarities and differences. We expose, in particular, the two main ways of modeling network formation. While the physics/applied mathematics approach is capable of reproducing most observed networks, it does not explain why they emerge. On the contrary, the economics approach is very precise in explaining why networks emerge but does a poor jo...

  3. Network Coding

    Indian Academy of Sciences (India)

    Network coding is a technique to increase the amount of information °ow in a network by mak- ing the key observation that information °ow is fundamentally different from commodity °ow. Whereas, under traditional methods of opera- tion of data networks, intermediate nodes are restricted to simply forwarding their incoming.

  4. Technical Network

    CERN Multimedia

    2007-01-01

    In order to optimise the management of the Technical Network (TN), to facilitate understanding of the purpose of devices connected to the TN and to improve security incident handling, the Technical Network Administrators and the CNIC WG have asked IT/CS to verify the "description" and "tag" fields of devices connected to the TN. Therefore, persons responsible for systems connected to the TN will receive e-mails from IT/CS asking them to add the corresponding information in the network database at "network-cern-ch". Thank you very much for your cooperation. The Technical Network Administrators & the CNIC WG

  5. Network science

    CERN Document Server

    Barabasi, Albert-Laszlo

    2016-01-01

    Networks are everywhere, from the Internet, to social networks, and the genetic networks that determine our biological existence. Illustrated throughout in full colour, this pioneering textbook, spanning a wide range of topics from physics to computer science, engineering, economics and the social sciences, introduces network science to an interdisciplinary audience. From the origins of the six degrees of separation to explaining why networks are robust to random failures, the author explores how viruses like Ebola and H1N1 spread, and why it is that our friends have more friends than we do. Using numerous real-world examples, this innovatively designed text includes clear delineation between undergraduate and graduate level material. The mathematical formulas and derivations are included within Advanced Topics sections, enabling use at a range of levels. Extensive online resources, including films and software for network analysis, make this a multifaceted companion for anyone with an interest in network sci...

  6. Vulnerability of network of networks

    Science.gov (United States)

    Havlin, S.; Kenett, D. Y.; Bashan, A.; Gao, J.; Stanley, H. E.

    2014-10-01

    Our dependence on networks - be they infrastructure, economic, social or others - leaves us prone to crises caused by the vulnerabilities of these networks. There is a great need to develop new methods to protect infrastructure networks and prevent cascade of failures (especially in cases of coupled networks). Terrorist attacks on transportation networks have traumatized modern societies. With a single blast, it has become possible to paralyze airline traffic, electric power supply, ground transportation or Internet communication. How, and at which cost can one restructure the network such that it will become more robust against malicious attacks? The gradual increase in attacks on the networks society depends on - Internet, mobile phone, transportation, air travel, banking, etc. - emphasize the need to develop new strategies to protect and defend these crucial networks of communication and infrastructure networks. One example is the threat of liquid explosives a few years ago, which completely shut down air travel for days, and has created extreme changes in regulations. Such threats and dangers warrant the need for new tools and strategies to defend critical infrastructure. In this paper we review recent advances in the theoretical understanding of the vulnerabilities of interdependent networks with and without spatial embedding, attack strategies and their affect on such networks of networks as well as recently developed strategies to optimize and repair failures caused by such attacks.

  7. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

    Hansen, Jonas; Roetter, Daniel Enrique Lucani; Krigslund, Jeppe

    2015-01-01

    . The inherent flexibility of both SDN and NC provides fertile ground to envision more efficient, robust, and secure networking designs, which may also incorporate content caching and storage, all of which are key challenges of the upcoming 5G networks. This article not only proposes the fundamentals......Software defined networking has garnered large attention due to its potential to virtualize services in the Internet, introducing flexibility in the buffering, scheduling, processing, and routing of data in network routers. SDN breaks the deadlock that has kept Internet network protocols stagnant...... for decades, while applications and physical links have evolved. This article advocates for the use of SDN to bring about 5G network services by incorporating network coding (NC) functionalities. The latter constitutes a major leap forward compared to the state-of-the- art store and forward Internet paradigm...

  8. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

    Krigslund, Jeppe; Hansen, Jonas; Roetter, Daniel Enrique Lucani

    2015-01-01

    Software Defined Networking (SDN) and Network Coding (NC) are two key concepts in networking that have garnered a large attention in recent years. On the one hand, SDN's potential to virtualize services in the Internet allows a large flexibility not only for routing data, but also to manage....... This paper advocates for the use of SDN to bring about future Internet and 5G network services by incorporating network coding (NC) functionalities. The inherent flexibility of both SDN and NC provides a fertile ground to envision more efficient, robust, and secure networking designs, that may also...... incorporate content caching and storage, all of which are key challenges of the future Internet and the upcoming 5G networks. This paper proposes some of the keys behind this intersection and supports it with use cases as well as a an implementation that integrated the Kodo library (NC) into OpenFlow (SDN...

  9. Telecommunication Networks

    DEFF Research Database (Denmark)

    Olsen, Rasmus Løvenstein; Balachandran, Kartheepan; Hald, Sara Ligaard

    2014-01-01

    In this chapter, we look into the role of telecommunication networks and their capability of supporting critical infrastructure systems and applications. The focus is on smart grids as the key driving example, bearing in mind that other such systems do exist, e.g., water management, traffic control......, etc. First, the role of basic communication is examined with a focus on critical infrastructures. We look at heterogenic networks and standards for smart grids, to give some insight into what has been done to ensure inter-operability in this direction. We then go to the physical network, and look...... at the deployment of the physical layout of the communication network and the related costs. This is an important aspect as one option to use existing networks is to deploy dedicated networks. Following this, we look at some generic models that describe reliability for accessing dynamic information. This part...

  10. Networked Identities

    DEFF Research Database (Denmark)

    Ryberg, Thomas; Larsen, Malene Charlotte

    2008-01-01

    In this article we take up a critique of the concept of Communities of Practice (CoP) voiced by several authors, who suggest that networks may provide a better metaphor to understand social forms of organisation and learning. Through a discussion of the notion of networked learning and the critique...... of CoPs we shall argue that the metaphor or theory of networked learning is itself confronted with some central tensions and challenges that need to be addressed. We then explore these theoretical and analytic challenges to the network metaphor, through an analysis of a Danish social networking site. We...... argue that understanding meaning-making and ‘networked identities’ may be relevant analytic entry points in navigating the challenges....

  11. Wireless Networks

    OpenAIRE

    Samaka, Mohammed; Khan, Khaled M.D.

    2007-01-01

    Wireless communication is the fastest-growing field in the telecommunication industry. Wireless networks have grown significantly as an important segment of the communications industry. They have become popular networks with the potential to provide high-speed, high-quality information exchange between two or more portable devices without any wire or conductors. Wireless networks can simply be characterized as the technology that provides seamless access to information, anywhere, anyplace, an...

  12. Enterpreneurial network

    OpenAIRE

    Thoma, Antonela; Nguyen, Lien; Kupsyte, Valdone

    2014-01-01

    Network has become more and more indispensable in the entrepreneurial world. Especially in startup businesses, network is crucial for new entrepreneurs. This project looks at how entrepreneurs in different sectors use network to become successful. We chose to work with three entrepreneurs from three companies that have been operational for a few years and conducted face to face interviews with them. Through the data from the interviews, we analyzed firstly what type of entrepreneurs they are,...

  13. Network security

    CERN Document Server

    Perez, André

    2014-01-01

    This book introduces the security mechanisms deployed in Ethernet, Wireless-Fidelity (Wi-Fi), Internet Protocol (IP) and MultiProtocol Label Switching (MPLS) networks. These mechanisms are grouped throughout the book according to the following four functions: data protection, access control, network isolation, and data monitoring. Data protection is supplied by data confidentiality and integrity control services. Access control is provided by a third-party authentication service. Network isolation is supplied by the Virtual Private Network (VPN) service. Data monitoring consists of applying

  14. Networking Japan

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    HIDA). Many of these alumni have and will in the future exchange ideas and keep contact not only to Japan, but also to fellow alumni around the globe and, thereby, practice south-south exchanges, which are made possible and traceable by their established alumni network and the World Network of Friends...... (WNF). Through the alumni network, Japan continues to infuse ideas to participants and alumni, who interpret and disseminate these ideas through alumni society networks and activities, but their discussions nationally and regionally also get reported back to Japan and affect future policies...

  15. Technical Network

    CERN Multimedia

    2007-01-01

    In order to optimize the management of the Technical Network (TN), to ease the understanding and purpose of devices connected to the TN, and to improve security incident handling, the Technical Network Administrators and the CNIC WG have asked IT/CS to verify the "description" and "tag" fields of devices connected to the TN. Therefore, persons responsible for systems connected to the TN will receive email notifications from IT/CS asking them to add the corresponding information in the network database. Thank you very much for your cooperation. The Technical Network Administrators & the CNIC WG

  16. Overlay networks toward information networking

    CERN Document Server

    Tarkoma, Sasu

    2010-01-01

    With their ability to solve problems in massive information distribution and processing, while keeping scaling costs low, overlay systems represent a rapidly growing area of R&D with important implications for the evolution of Internet architecture. Inspired by the author's articles on content based routing, Overlay Networks: Toward Information Networking provides a complete introduction to overlay networks. Examining what they are and what kind of structures they require, the text covers the key structures, protocols, and algorithms used in overlay networks. It reviews the current state of th

  17. Heterodox networks

    DEFF Research Database (Denmark)

    Lala, Purnima; Kumar, Ambuj

    2016-01-01

    It is imperative for the service providers to bring innovation in the network design to meet the exponential growth of mobile subscribers for multi-technology future wireless networks. As a matter of research, studies on providing services to moving subscriber groups aka ‘Place Time Capacity (PTC...

  18. Sensor networks

    NARCIS (Netherlands)

    Chatterjea, Supriyo; Thurston, J.; Kininmonth, S.; Havinga, Paul J.M.

    2006-01-01

    This article describes the details of a sensor network that is currently being deployed at the Great Barrier Reef in Australia. The sensor network allows scientists to retrieve sensor data that has a high spatial and temporal resolution. We give an overview of the energy-efficient data aggregation

  19. Network Protocols

    NARCIS (Netherlands)

    Tanenbaum, A.S.

    1981-01-01

    Dunng the last ten years, many computer networks have been designed, implemented, and put into service in the United States, Canada, Europe, Japan, and elsewhere. From the experience obtamed with these networks, certain key design principles have begun to emerge, principles that can be used to

  20. Probabilistic Networks

    DEFF Research Database (Denmark)

    Jensen, Finn Verner; Lauritzen, Steffen Lilholt

    2001-01-01

    This article describes the basic ideas and algorithms behind specification and inference in probabilistic networks based on directed acyclic graphs, undirected graphs, and chain graphs.......This article describes the basic ideas and algorithms behind specification and inference in probabilistic networks based on directed acyclic graphs, undirected graphs, and chain graphs....

  1. Organizational Networks

    DEFF Research Database (Denmark)

    Sørensen, Ole Henning; Grande, Bård

    1996-01-01

    The paper focuses on the concept of organizational networks. Four different uses of the concept are identified and critically discussed.......The paper focuses on the concept of organizational networks. Four different uses of the concept are identified and critically discussed....

  2. Affective Networks

    OpenAIRE

    Jodi Dean

    2010-01-01

    This article sets out the idea of affective networks as a constitutive feature of communicative capitalism. It explores the circulation of intensities in contemporary information and communication networks, arguing that this circulation should be theorized in terms of the psychoanalytic notion of the drive. The article includes critical engagements with theorists such as Guy Debord, Jacques Lacan, Tiziana Terranova, and Slavoj Zizek.

  3. Network chemistry, network toxicology, network informatics, and network behavioristics: A scientific outline

    OpenAIRE

    WenJun Zhang

    2016-01-01

    In present study, I proposed some new sciences: network chemistry, network toxicology, network informatics, and network behavioristics. The aims, scope and scientific foundation of these sciences are outlined.

  4. Network Affordances

    DEFF Research Database (Denmark)

    Samson, Audrey; Soon, Winnie

    2015-01-01

    This paper examines the notion of network affordance within the context of network art. Building on Gibson's theory (Gibson, 1979) we understand affordance as the perceived and actual parameters of a thing. We expand on Gaver's affordance of predictability (Gaver, 1996) to include ecological...... and computational parameters of unpredictability. We illustrate the notion of unpredictability by considering four specific works that were included in a network art exhibiton, SPEED SHOW [2.0] Hong Kong. The paper discusses how the artworks are contingent upon the parameteric relations (Parisi, 2013......), of the network. We introduce network affordance as a dynamic framework that could articulate the experienced tension arising from the (visible) symbolic representation of computational processes and its hidden occurrences. We base our proposal on the experience of both organising the SPEED SHOW and participating...

  5. Social networks

    CERN Document Server

    Etaner-Uyar, A Sima

    2014-01-01

    The present volume provides a comprehensive resource for practitioners and researchers alike-both those new to the field as well as those who already have some experience. The work covers Social Network Analysis theory and methods with a focus on current applications and case studies applied in various domains such as mobile networks, security, machine learning and health. With the increasing popularity of Web 2.0, social media has become a widely used communication platform. Parallel to this development, Social Network Analysis gained in importance as a research field, while opening up many

  6. Network Warrior

    CERN Document Server

    Donahue, Gary

    2011-01-01

    Pick up where certification exams leave off. With this practical, in-depth guide to the entire network infrastructure, you'll learn how to deal with real Cisco networks, rather than the hypothetical situations presented on exams like the CCNA. Network Warrior takes you step by step through the world of routers, switches, firewalls, and other technologies based on the author's extensive field experience. You'll find new content for MPLS, IPv6, VoIP, and wireless in this completely revised second edition, along with examples of Cisco Nexus 5000 and 7000 switches throughout. Topics include: An

  7. Managing Networks

    DEFF Research Database (Denmark)

    Jørgensen, Heidi; Vintergaard, Christian

    Logically it seems that companies pursuing different business strategies wouldalso manage their relationships with other firms accordingly. Nevertheless, due tothe lack of research in the field of network strategies, this link still remainsinadequately examined. Based on the well-known framework...... isprovided, that the relation between a company's strategy, structure and processesin fact have a considerable influence on its pattern of network behaviour. Threecase studies from the Danish biotech industry exemplify and illustrate how acompany's strategy is directly correlated with how it manages its...... of organisationalbehaviour developed by Miles and Snow (1978), this paper argues that thepatterns of network behaviour practiced by firms greatly depend on the businesstypology of the company. That is, a company's business typology will to a certaindegree dictate the network identity of the company. In this paper evidence...

  8. Heterodox networks

    DEFF Research Database (Denmark)

    Lala, Purnima; Kumar, Ambuj

    2016-01-01

    architecture of ‘Hovering Ad-hoc Network (HANET)’ for the latter will be deployed to assist and manage the overloaded primary base stations enhancing the on-demand coverage and capacity of the entire system. Proposed modes can either operate independently or as a cascaded architecture to form a Heterodox......It is imperative for the service providers to bring innovation in the network design to meet the exponential growth of mobile subscribers for multi-technology future wireless networks. As a matter of research, studies on providing services to moving subscriber groups aka ‘Place Time Capacity (PTC......)’ have not been considered much in the literature. In this article we present Heterodox networks as an innovative and alternate approach to handle the PTC congestion. We describe two different approaches to combat the PTC congestion where the traditional terrestrial infrastructure fails to provide...

  9. Exchange Network

    Science.gov (United States)

    The Environmental Information Exchange Network (EIEN) is an Internet-based system used by state, tribal and territorial partners to securely share environmental and health information with one another and EPA.

  10. Sentinel Network

    Science.gov (United States)

    The Sentinel Network is an integrated, electronic, national medical product safety initiative that compiles information about the safe and effective use of medical products accessible to patients and healthcare practitioners.

  11. computer networks

    Directory of Open Access Journals (Sweden)

    N. U. Ahmed

    2002-01-01

    Full Text Available In this paper, we construct a new dynamic model for the Token Bucket (TB algorithm used in computer networks and use systems approach for its analysis. This model is then augmented by adding a dynamic model for a multiplexor at an access node where the TB exercises a policing function. In the model, traffic policing, multiplexing and network utilization are formally defined. Based on the model, we study such issues as (quality of service QoS, traffic sizing and network dimensioning. Also we propose an algorithm using feedback control to improve QoS and network utilization. Applying MPEG video traces as the input traffic to the model, we verify the usefulness and effectiveness of our model.

  12. Affective Networks

    Directory of Open Access Journals (Sweden)

    Jodi Dean

    2010-02-01

    Full Text Available This article sets out the idea of affective networks as a constitutive feature of communicative capitalism. It explores the circulation of intensities in contemporary information and communication networks, arguing that this circulation should be theorized in terms of the psychoanalytic notion of the drive. The article includes critical engagements with theorists such as Guy Debord, Jacques Lacan, Tiziana Terranova, and Slavoj Zizek.

  13. Friendship Networks

    OpenAIRE

    Jan K. Brueckner

    2004-01-01

    Building upon a long tradition in sociology, economists have recently turned their attention to the analysis of social networks. The present paper adds to this emerging literature by proposing a different approach to social-network formation. As in the model of Jackson and Wolinsky (1996), formation of a link between two individuals requires two-sided investments in the present framework. But in contrast to their approach, where the required investments are exogenously specified and link form...

  14. Developer Network

    Energy Technology Data Exchange (ETDEWEB)

    2012-08-21

    NREL's Developer Network, developer.nrel.gov, provides data that users can access to provide data to their own analyses, mobile and web applications. Developers can retrieve the data through a Web services API (application programming interface). The Developer Network handles overhead of serving up web services such as key management, authentication, analytics, reporting, documentation standards, and throttling in a common architecture, while allowing web services and APIs to be maintained and managed independently.

  15. Network Power Fault Detection

    OpenAIRE

    Siviero, Claudio

    2013-01-01

    Network power fault detection. At least one first network device is instructed to temporarily disconnect from a power supply path of a network, and at least one characteristic of the power supply path of the network is measured at a second network device connected to the network while the at least one first network device is temporarily disconnected from the network

  16. Complex Networks

    CERN Document Server

    Evsukoff, Alexandre; González, Marta

    2013-01-01

    In the last decade we have seen the emergence of a new inter-disciplinary field focusing on the understanding of networks which are dynamic, large, open, and have a structure sometimes called random-biased. The field of Complex Networks is helping us better understand many complex phenomena such as the spread of  deseases, protein interactions, social relationships, to name but a few. Studies in Complex Networks are gaining attention due to some major scientific breakthroughs proposed by network scientists helping us understand and model interactions contained in large datasets. In fact, if we could point to one event leading to the widespread use of complex network analysis is the availability of online databases. Theories of Random Graphs from Erdös and Rényi from the late 1950s led us to believe that most networks had random characteristics. The work on large online datasets told us otherwise. Starting with the work of Barabási and Albert as well as Watts and Strogatz in the late 1990s, we now know th...

  17. Sentient networks

    Energy Technology Data Exchange (ETDEWEB)

    Chapline, G.

    1998-03-01

    The engineering problems of constructing autonomous networks of sensors and data processors that can provide alerts for dangerous situations provide a new context for debating the question whether man-made systems can emulate the cognitive capabilities of the mammalian brain. In this paper we consider the question whether a distributed network of sensors and data processors can form ``perceptions`` based on sensory data. Because sensory data can have exponentially many explanations, the use of a central data processor to analyze the outputs from a large ensemble of sensors will in general introduce unacceptable latencies for responding to dangerous situations. A better idea is to use a distributed ``Helmholtz machine`` architecture in which the sensors are connected to a network of simple processors, and the collective state of the network as a whole provides an explanation for the sensory data. In general communication within such a network will require time division multiplexing, which opens the door to the possibility that with certain refinements to the Helmholtz machine architecture it may be possible to build sensor networks that exhibit a form of artificial consciousness.

  18. Network interruptions

    CERN Document Server

    2005-01-01

    On Sunday 12 June 2005, a site-wide security software upgrade will be performed on all CERN network equipment. This maintenance operation will cause at least 2 short network interruptions of 2 minutes on each equipment item. There are hundreds of such items across the CERN site (Meyrin, Prévessin and all SPS and LHC pits), and it will thus take the whole day to treat them all. All network users and services will be affected. Central batch computing services will be interrupted during this period, expected to last from 8 a.m. until late evening. Job submission will still be possible but no jobs will actually be run. It is hoped to complete the computer centre upgrades in the morning so that stable access can be restored to lxplus, afs and nice services as soon as possible; this cannot be guaranteed, however. The opportunity will be used to interrupt and perform upgrades on the CERN Document Servers.

  19. Network Survivability

    DEFF Research Database (Denmark)

    Marzo, José L.; Stidsen, Thomas Riis; Ruepp, Sarah Renée

    2010-01-01

    – are vital to modern services such as mobile telephony, online banking and VoIP. This book examines communication networking from a mathematical viewpoint. The contributing authors took part in the European COST action 293 – a four-year program of multidisciplinary research on this subject. In this book...... they offer introductory overviews and state-of-the-art assessments of current and future research in the fields of broadband, optical, wireless and ad hoc networks. Particular topics of interest are design, optimization, robustness and energy consumption. The book will be of interest to graduate students......, researchers and practitioners in the areas of networking, theoretical computer science, operations research, distributed computing and mathematics....

  20. Nuclear networking.

    Science.gov (United States)

    Xie, Wei; Burke, Brian

    2017-07-04

    Nuclear lamins are intermediate filament proteins that represent important structural components of metazoan nuclear envelopes (NEs). By combining proteomics and superresolution microscopy, we recently reported that both A- and B-type nuclear lamins form spatially distinct filament networks at the nuclear periphery of mouse fibroblasts. In particular, A-type lamins exhibit differential association with nuclear pore complexes (NPCs). Our studies reveal that the nuclear lamina network in mammalian somatic cells is less ordered and more complex than that of amphibian oocytes, the only other system in which the lamina has been visualized at high resolution. In addition, the NPC component Tpr likely links NPCs to the A-type lamin network, an association that appears to be regulated by C-terminal modification of various A-type lamin isoforms. Many questions remain, however, concerning the structure and assembly of lamin filaments, as well as with their mode of association with other nuclear components such as peripheral chromatin.

  1. Industrial Networks

    DEFF Research Database (Denmark)

    Karlsson, Christer

    2015-01-01

    the focus of operations management from managing the own organization to continuously developing and managing a network of external and internal resources forming a production system. This perspective may be called managing an “extraprise” rather than an “enterprise.” It should be noted that “an industrial...... network” should not be seen as an organizational form but as a perspective that can be used to enrich one's understanding of organizations. The industrial network perspective has three basic building blocks: actors, resources, and activities. The three building blocks and their relations constitute...

  2. Nepal Networking

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    that their personal networks engage not only their families, but also their home communities and by extension Nepal. The two women constitute weak links between their country and other countries and as such they function as bridges or channels for transmission of practices, ideas, knowledge, and artefacts. However...

  3. Network Society

    DEFF Research Database (Denmark)

    Clausen, Lars; Tække, Jesper

    2018-01-01

    the five strands of theory on the network society. Each theoretical position has its specific implications for acting toward strategic goals. In its entirety, the five perspectives give a thorough understanding of the conditions for successful strategic communication in the 21st century....

  4. Network Coding

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 7. Network Coding. K V Rashmi Nihar B Shah P Vijay Kumar. General Article Volume 15 Issue 7 July 2010 pp 604-621. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/015/07/0604-0621. Keywords.

  5. Network Society

    DEFF Research Database (Denmark)

    Clausen, Lars; Tække, Jesper

    2017-01-01

    the five strands of theory on the network society. Each theoretical position has its specific implications for acting toward strategic goals. In its entirety, the five perspectives give a thorough understanding of the conditions for successful strategic communication in the 21st century....

  6. distribution network

    African Journals Online (AJOL)

    user

    This paper examined the acidic properties of distribution transformer oil insulation in service at Jericho distribution network Ibadan, Nigeria. Five oil samples each from six distribution transformers (DT1, DT2, DT3, DT4 and DT5) making a total of thirty samples were taken from different installed distribution transformers all ...

  7. Social Networks and Network Structures

    Science.gov (United States)

    2006-11-01

    Research in Command & Control • Latent Semantic Analysis – Team communication – Emergent team dynamics – Shared situation awareness • Dynamic Network...requirements – Information technology requirements 28 LSA Essentials of Latent Semantic Analysis 29 Communication Analysis • Goal: Automatically monitor and

  8. Introduction to neural networks

    CERN Document Server

    James, Frederick E

    1994-02-02

    1. Introduction and overview of Artificial Neural Networks. 2,3. The Feed-forward Network as an inverse Problem, and results on the computational complexity of network training. 4.Physics applications of neural networks.

  9. Network gravity

    Science.gov (United States)

    Lombard, John

    2017-01-01

    We introduce the construction of a new framework for probing discrete emergent geometry and boundary-boundary observables based on a fundamentally a-dimensional underlying network structure. Using a gravitationally motivated action with Forman weighted combinatorial curvatures and simplicial volumes relying on a decomposition of an abstract simplicial complex into realized embeddings of proper skeletons, we demonstrate properties such as a minimal volume-scale cutoff, the necessity of a term playing the role of a positive definite cosmological constant as a regulator for nondegenerate geometries, and naturally emergent simplicial structures from Metropolis network evolution simulations with no restrictions on attachment rules or regular building blocks. We see emergent properties which echo results from both the spinfoam formalism and causal dynamical triangulations in quantum gravity, and provide analytical and numerical results to support the analogy. We conclude with a summary of open questions and intent for future work in developing the program.

  10. Neural Networks

    Directory of Open Access Journals (Sweden)

    Schwindling Jerome

    2010-04-01

    Full Text Available This course presents an overview of the concepts of the neural networks and their aplication in the framework of High energy physics analyses. After a brief introduction on the concept of neural networks, the concept is explained in the frame of neuro-biology, introducing the concept of multi-layer perceptron, learning and their use as data classifer. The concept is then presented in a second part using in more details the mathematical approach focussing on typical use cases faced in particle physics. Finally, the last part presents the best way to use such statistical tools in view of event classifers, putting the emphasis on the setup of the multi-layer perceptron. The full article (15 p. corresponding to this lecture is written in french and is provided in the proceedings of the book SOS 2008.

  11. Network Frontier Workshop 2013

    Science.gov (United States)

    2014-11-11

    networks, biological networks, cognitive and semantic networks and social networks. This field has received a major boost caused by the availability of huge...networks, which require new ways of thinking about the world. Part of the new cognition is provided by the fractional calculus description of temporal...structures in a wide range of examples—including road networks in large urban areas, a rabbit warren, a dolphin social network, a European interbank network

  12. Linear network theory

    CERN Document Server

    Sander, K F

    1964-01-01

    Linear Network Theory covers the significant algebraic aspect of network theory, with minimal reference to practical circuits. The book begins the presentation of network analysis with the exposition of networks containing resistances only, and follows it up with a discussion of networks involving inductance and capacity by way of the differential equations. Classification and description of certain networks, equivalent networks, filter circuits, and network functions are also covered. Electrical engineers, technicians, electronics engineers, electricians, and students learning the intricacies

  13. Surface Networks

    OpenAIRE

    Kostrikov, Ilya; Bruna, Joan; Panozzo, Daniele; Zorin, Denis

    2017-01-01

    We study data-driven representations for three-dimensional triangle meshes, which are one of the prevalent objects used to represent 3D geometry. Recent works have developed models that exploit the intrinsic geometry of manifolds and graphs, namely the Graph Neural Networks (GNNs) and its spectral variants, which learn from the local metric tensor via the Laplacian operator. Despite offering excellent sample complexity and built-in invariances, intrinsic geometry alone is invariant to isometr...

  14. Loss Networks

    OpenAIRE

    Kelly, F. P.

    1991-01-01

    This paper describes work on the stochastic modelling of loss networks. Such systems have long been of interest to telephone engineers and are becoming increasingly important as models of computer and information systems. Throughout the century problems from this field have provided an impetus to the development of probability theory, pure and applied. This paper provides an introduction to the area and a review of recent work.

  15. Modeling the citation network by network cosmology.

    Science.gov (United States)

    Xie, Zheng; Ouyang, Zhenzheng; Zhang, Pengyuan; Yi, Dongyun; Kong, Dexing

    2015-01-01

    Citation between papers can be treated as a causal relationship. In addition, some citation networks have a number of similarities to the causal networks in network cosmology, e.g., the similar in-and out-degree distributions. Hence, it is possible to model the citation network using network cosmology. The casual network models built on homogenous spacetimes have some restrictions when describing some phenomena in citation networks, e.g., the hot papers receive more citations than other simultaneously published papers. We propose an inhomogenous causal network model to model the citation network, the connection mechanism of which well expresses some features of citation. The node growth trend and degree distributions of the generated networks also fit those of some citation networks well.

  16. Modeling the citation network by network cosmology.

    Directory of Open Access Journals (Sweden)

    Zheng Xie

    Full Text Available Citation between papers can be treated as a causal relationship. In addition, some citation networks have a number of similarities to the causal networks in network cosmology, e.g., the similar in-and out-degree distributions. Hence, it is possible to model the citation network using network cosmology. The casual network models built on homogenous spacetimes have some restrictions when describing some phenomena in citation networks, e.g., the hot papers receive more citations than other simultaneously published papers. We propose an inhomogenous causal network model to model the citation network, the connection mechanism of which well expresses some features of citation. The node growth trend and degree distributions of the generated networks also fit those of some citation networks well.

  17. Open innovation in networks

    DEFF Research Database (Denmark)

    Hu, Yimei

    Open innovation in networks has been a popular topic for long, this paper rethinks the concepts of innovation network and network organization, and clarifies the differences between them based on the network perspective. Network perspective means that: network is the context of firms; market...... and hierarchy can be analyzed from a network approach. Within a network perspective, there are different levels of network, and a firm may not always has the power to “manage” innovation networks due to different levels of power. Based on the strength of a firm’s power, its role may varies from manager...

  18. ENLIGHT Network

    CERN Multimedia

    Ballantine, A; Dixon-Altaber, H; Dosanjh, M; Kuchina, L

    2011-01-01

    State-of-the-art techniques borrowed from particle accelerators and detectors are a key element in hadrontherapy and several European projects are actively fostering the collaboration amongst the various disciplines and countries. ENLIGHT was established in 2002 to coordinate these European efforts in hadron therapy. The ENLIGHT network is formed by the European hadrontherapy Community, with more than 300 participants from twenty European countries. A major achievement of ENLIGHT has been the blending of traditionally separate communities so that clinicians, physicists, biologists and engineers with experience and interest in particle therapy are working together.

  19. Local Social Networks

    OpenAIRE

    Sapuppo, Antonio; Sørensen, Lene Tolstrup

    2011-01-01

    Online social networks have become essential for many users in their daily communication. Through a combination of the online social networks with opportunistic networks, a new concept arises: Local Social Networks. The target of local social networks is to promote social networking benefits in physical environment in order to leverage personal affinities in the users' surroundings. The purpose of this paper is to present and discuss the concept of local social networks as a new social commun...

  20. Connectivity of communication networks

    CERN Document Server

    Mao, Guoqiang

    2017-01-01

    This book introduces a number of recent developments on connectivity of communication networks, ranging from connectivity of large static networks and connectivity of highly dynamic networks to connectivity of small to medium sized networks. This book also introduces some applications of connectivity studies in network optimization, in network localization, and in estimating distances between nodes. The book starts with an overview of the fundamental concepts, models, tools, and methodologies used for connectivity studies. The rest of the chapters are divided into four parts: connectivity of large static networks, connectivity of highly dynamic networks, connectivity of small to medium sized networks, and applications of connectivity studies.

  1. Network Science Experimentation Vision

    Science.gov (United States)

    2015-09-01

    capabilities and performance of a heterogeneous collection of interdependent networks . This report outlines and discusses an experimentation vision that...has been shown to depend upon the capabilities and performance of a heterogeneous collection of interdependent networks . Such a collection of networks ...well as tactical military networks . In particular, wireless tactical networks can be simulated with high fidelity, using off the shelf simulation

  2. Introduction to computer networking

    CERN Document Server

    Robertazzi, Thomas G

    2017-01-01

    This book gives a broad look at both fundamental networking technology and new areas that support it and use it. It is a concise introduction to the most prominent, recent technological topics in computer networking. Topics include network technology such as wired and wireless networks, enabling technologies such as data centers, software defined networking, cloud and grid computing and applications such as networks on chips, space networking and network security. The accessible writing style and non-mathematical treatment makes this a useful book for the student, network and communications engineer, computer scientist and IT professional. • Features a concise, accessible treatment of computer networking, focusing on new technological topics; • Provides non-mathematical introduction to networks in their most common forms today;< • Includes new developments in switching, optical networks, WiFi, Bluetooth, LTE, 5G, and quantum cryptography.

  3. Animal transportation networks

    Science.gov (United States)

    Perna, Andrea; Latty, Tanya

    2014-01-01

    Many group-living animals construct transportation networks of trails, galleries and burrows by modifying the environment to facilitate faster, safer or more efficient movement. Animal transportation networks can have direct influences on the fitness of individuals, whereas the shape and structure of transportation networks can influence community dynamics by facilitating contacts between different individuals and species. In this review, we discuss three key areas in the study of animal transportation networks: the topological properties of networks, network morphogenesis and growth, and the behaviour of network users. We present a brief primer on elements of network theory, and then discuss the different ways in which animal groups deal with the fundamental trade-off between the competing network properties of travel efficiency, robustness and infrastructure cost. We consider how the behaviour of network users can impact network efficiency, and call for studies that integrate both network topology and user behaviour. We finish with a prospectus for future research. PMID:25165598

  4. Visualization of Social Networks

    NARCIS (Netherlands)

    Boertjes, E.M.; Kotterink, B.; Jager, E.J.

    2011-01-01

    Current visualizations of social networks are mostly some form of node-link diagram. Depending on the type of social network, this can be some treevisualization with a strict hierarchical structure or a more generic network visualization.

  5. Collaborative networks: Reference modeling

    NARCIS (Netherlands)

    Camarinha-Matos, L.M.; Afsarmanesh, H.

    2008-01-01

    Collaborative Networks: Reference Modeling works to establish a theoretical foundation for Collaborative Networks. Particular emphasis is put on modeling multiple facets of collaborative networks and establishing a comprehensive modeling framework that captures and structures diverse perspectives of

  6. Computer networks monitoring

    OpenAIRE

    Antončič , Polona

    2012-01-01

    The present thesis entitled Computer Networks Monitoring introduces the basics of computer networks, the aim and the computer data reclamation from networking devices, software for the system follow-up together with the case of monitoring a real network with tens of network devices. The networks represent an important part in the modern information technology and serve for the exchange of data and sources which makes their impeccability of crucial importance. Correct and efficient sys...

  7. Packet Tracer network simulator

    CERN Document Server

    Jesin, A

    2014-01-01

    A practical, fast-paced guide that gives you all the information you need to successfully create networks and simulate them using Packet Tracer.Packet Tracer Network Simulator is aimed at students, instructors, and network administrators who wish to use this simulator to learn how to perform networking instead of investing in expensive, specialized hardware. This book assumes that you have a good amount of Cisco networking knowledge, and it will focus more on Packet Tracer rather than networking.

  8. Basics of Computer Networking

    CERN Document Server

    Robertazzi, Thomas

    2012-01-01

    Springer Brief Basics of Computer Networking provides a non-mathematical introduction to the world of networks. This book covers both technology for wired and wireless networks. Coverage includes transmission media, local area networks, wide area networks, and network security. Written in a very accessible style for the interested layman by the author of a widely used textbook with many years of experience explaining concepts to the beginner.

  9. Percolation in clustered networks

    OpenAIRE

    Miller, Joel C

    2009-01-01

    The social networks that infectious diseases spread along are typically clustered. Because of the close relation between percolation and epidemic spread, the behavior of percolation in such networks gives insight into infectious disease dynamics. A number of authors have studied clustered networks, but the networks often contain preferential mixing between high degree nodes. We introduce a class of random clustered networks and another class of random unclustered networks with the same prefer...

  10. Cyber Network Mission Dependencies

    Science.gov (United States)

    2015-09-18

    or she must make. Network Mapping System ( NeMS ) is a software-based tool created by the Lawrence Livermore National Laboratory to discover and map...network assets in support of cyber situational awareness [10]. NeMS combines both active probes and passive monitoring of network data to map the network...security settings in order to maximize efficiency without disrupting network activities. Tests of NeMS in control networks yielded great results, as

  11. The Economics of Networking

    DEFF Research Database (Denmark)

    Sørensen, Olav Jull

    The literature on business networks is often oversocialized. The economic side of business is implicitly assumed. This paper analyses the economics of network behavior by loking at each of the key concepts in the Network Theory.......The literature on business networks is often oversocialized. The economic side of business is implicitly assumed. This paper analyses the economics of network behavior by loking at each of the key concepts in the Network Theory....

  12. Stem Cell Networks

    OpenAIRE

    Werner, Eric

    2016-01-01

    We present a general computational theory of stem cell networks and their developmental dynamics. Stem cell networks are special cases of developmental control networks. Our theory generates a natural classification of all possible stem cell networks based on their network architecture. Each stem cell network has a unique topology and semantics and developmental dynamics that result in distinct phenotypes. We show that the ideal growth dynamics of multicellular systems generated by stem cell ...

  13. Statistical network analysis for analyzing policy networks

    DEFF Research Database (Denmark)

    Robins, Garry; Lewis, Jenny; Wang, Peng

    2012-01-01

    To analyze social network data using standard statistical approaches is to risk incorrect inference. The dependencies among observations implied in a network conceptualization undermine standard assumptions of the usual general linear models. One of the most quickly expanding areas of social...... and policy network methodology is the development of statistical modeling approaches that can accommodate such dependent data. In this article, we review three network statistical methods commonly used in the current literature: quadratic assignment procedures, exponential random graph models (ERGMs...

  14. Airborne Network Optimization with Dynamic Network Update

    Science.gov (United States)

    2015-03-26

    Faculty Department of Electrical and Computer Engineering Graduate School of Engineering and Management Air Force Institute of Technology Air University...require small amounts of network bandwidth to perform routing. This thesis advocates the use of Kalman filters to predict network congestion in...airborne networks. Intelligent agents can make use of Kalman filter predictions to make informed decisions to manage communication in airborne networks. The

  15. Next Generation Networks

    Directory of Open Access Journals (Sweden)

    Ladislav Schwartz

    2006-01-01

    Full Text Available Two network types had been existing in Slovakia by the end of the year 2004 – public switched telephone network – PSTN and packet switched data network – DCN. The other network, known as the next generation network – NGN, has been put into operation since the beginning of the year 2005. The role of the next generation network is to merge the both previous network types into one unified complex network with the full centralised control, based on routing and packet switching. The T-Com company (previous Slovak Telecom was the first who did it.

  16. Coded Network Function Virtualization

    DEFF Research Database (Denmark)

    Al-Shuwaili, A.; Simone, O.; Kliewer, J.

    2016-01-01

    Network function virtualization (NFV) prescribes the instantiation of network functions on general-purpose network devices, such as servers and switches. While yielding a more flexible and cost-effective network architecture, NFV is potentially limited by the fact that commercial off-the-shelf ha......Network function virtualization (NFV) prescribes the instantiation of network functions on general-purpose network devices, such as servers and switches. While yielding a more flexible and cost-effective network architecture, NFV is potentially limited by the fact that commercial off...

  17. Local Social Networks

    DEFF Research Database (Denmark)

    Sapuppo, Antonio; Sørensen, Lene Tolstrup

    2011-01-01

    in physical environment in order to leverage personal affinities in the users' surroundings. The purpose of this paper is to present and discuss the concept of local social networks as a new social communication system. Particularly, the preliminary architecture and the prototype of local social networks......Online social networks have become essential for many users in their daily communication. Through a combination of the online social networks with opportunistic networks, a new concept arises: Local Social Networks. The target of local social networks is to promote social networking benefits...

  18. Cesarean scar pregnancy treated by curettage and aspiration guided by laparoscopy

    Directory of Open Access Journals (Sweden)

    Shu S

    2015-08-01

    Full Text Available Shan-rong Shu, Xin Luo, Zhi-xin Wang, Yu-hong Yao Department of Obstetrics and Gynecology, The First Affiliated Hospital of JiNan University, HuangPu Road West, Guangzhou, People’s Republic of China Abstract: Pregnancy in a cesarean scar is the rarest form of an ectopic pregnancy. The treatment for cesarean scar pregnancy mainly includes systemic methotrexate and uterine artery embolization. Here, we reported a case of cesarean scar pregnancy treated by curettage and aspiration guided by laparoscopy. The treatment plan included two phases. Three days after a combination of methotrexate and mifepristone was administered, the gestational sac was removed under laparoscopy, which enabled a successful treatment for the unruptured ectopic pregnancy in a previous cesarean scar and made it possible to preserve the reproductive capability of the patient. Keywords: cesarean scar pregnancy, laparoscopy, curettage and aspiration 

  19. Formation of multiple networks

    DEFF Research Database (Denmark)

    Magnani, Matteo; Rossi, Luca

    2013-01-01

    While most research in Social Network Analysis has focused on single networks, the availability of complex on-line data about individuals and their mutual heterogenous connections has recently determined a renewed interest in multi-layer network analysis. To the best of our knowledge, in this paper...... we introduce the first network formation model for multiple networks. Network formation models are among the most popular tools in traditional network studies, because of both their practical and theoretical impact. However, existing models are not sufficient to describe the generation of multiple...... networks. Our model, motivated by an empirical analysis of real multi-layered network data, is a conservative extension of single-network models and emphasizes the additional level of complexity that we experience when we move from a single- to a more complete and realistic multi-network context....

  20. Noisy Network Coding

    CERN Document Server

    Lim, Sung Hoon; Gamal, Abbas El; Chung, Sae-Young

    2010-01-01

    A noisy network coding scheme for sending multiple sources over a general noisy network is presented. For multi-source multicast networks, the scheme naturally extends both network coding over noiseless networks by Ahlswede, Cai, Li, and Yeung, and compress-forward coding for the relay channel by Cover and El Gamal to general discrete memoryless and Gaussian networks. The scheme also recovers as special cases the results on coding for wireless relay networks and deterministic networks by Avestimehr, Diggavi, and Tse, and coding for wireless erasure networks by Dana, Gowaikar, Palanki, Hassibi, and Effros. The scheme involves message repetition coding, relay signal compression, and simultaneous decoding. Unlike previous compress--forward schemes, where independent messages are sent over multiple blocks, the same message is sent multiple times using independent codebooks as in the network coding scheme for cyclic networks. Furthermore, the relays do not use Wyner--Ziv binning as in previous compress-forward sch...

  1. Identity and Professional Networking.

    Science.gov (United States)

    Raj, Medha; Fast, Nathanael J; Fisher, Oliver

    2017-06-01

    Despite evidence that large professional networks afford a host of financial and professional benefits, people vary in how motivated they are to build such networks. To help explain this variance, the present article moves beyond a rational self-interest account to examine the possibility that identity shapes individuals' intentions to network. Study 1 established a positive association between viewing professional networking as identity-congruent and the tendency to prioritize strengthening and expanding one's professional network. Study 2 revealed that manipulating the salience of the self affects networking intentions, but only among those high in networking identity-congruence. Study 3 further established causality by experimentally manipulating identity-congruence to increase networking intentions. Study 4 examined whether identity or self-interest is a better predictor of networking intentions, providing support for the former. These findings indicate that identity influences the networks people develop. Implications for research on the self, identity-based motivation, and professional networking are discussed.

  2. Engineering technology for networks

    Science.gov (United States)

    Paul, Arthur S.; Benjamin, Norman

    1991-01-01

    Space Network (SN) modeling and evaluation are presented. The following tasks are included: Network Modeling (developing measures and metrics for SN, modeling of the Network Control Center (NCC), using knowledge acquired from the NCC to model the SNC, and modeling the SN); and Space Network Resource scheduling.

  3. Technologies for Home Networking

    DEFF Research Database (Denmark)

    A broad overview of the home networking field, ranging from wireless technologies to practical applications. In the future, it is expected that private networks (e.g. home networks) will become part of the global network ecosystem, participating in sharing their own content, running IP...

  4. Energy Efficient Digital Networks

    Energy Technology Data Exchange (ETDEWEB)

    Lanzisera, Steven [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Brown, Richard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-01-01

    Digital networks are the foundation of the information services, and play an expanding and indispensable role in our lives, via the Internet, email, mobile phones, etc. However, these networks consume energy, both through the direct energy use of the network interfaces and equipment that comprise the network, and in the effect they have on the operating patterns of devices connected to the network. The purpose of this research was to investigate a variety of technology and policy issues related to the energy use caused by digital networks, and to further develop several energy-efficiency technologies targeted at networks.

  5. Multilayer Social Networks

    DEFF Research Database (Denmark)

    Dickison, Mark; Magnani, Matteo; Rossi, Luca

    Multilayer networks, in particular multilayer social networks, where users belong to and interact on different networks at the same time, are an active research area in social network analysis, computer science, and physics. These networks have traditionally been studied within these separate...... social network systems, the evolution of interconnected social networks, and dynamic processes such as information spreading. A single real dataset is used to illustrate the concepts presented throughout the book, demonstrating both the practical utility and the potential shortcomings of the various...

  6. Networking for big data

    CERN Document Server

    Yu, Shui; Misic, Jelena; Shen, Xuemin (Sherman)

    2015-01-01

    Networking for Big Data supplies an unprecedented look at cutting-edge research on the networking and communication aspects of Big Data. Starting with a comprehensive introduction to Big Data and its networking issues, it offers deep technical coverage of both theory and applications.The book is divided into four sections: introduction to Big Data, networking theory and design for Big Data, networking security for Big Data, and platforms and systems for Big Data applications. Focusing on key networking issues in Big Data, the book explains network design and implementation for Big Data. It exa

  7. Epidemics on interconnected networks

    Science.gov (United States)

    Dickison, Mark; Havlin, S.; Stanley, H. E.

    2012-06-01

    Populations are seldom completely isolated from their environment. Individuals in a particular geographic or social region may be considered a distinct network due to strong local ties but will also interact with individuals in other networks. We study the susceptible-infected-recovered process on interconnected network systems and find two distinct regimes. In strongly coupled network systems, epidemics occur simultaneously across the entire system at a critical infection strength βc, below which the disease does not spread. In contrast, in weakly coupled network systems, a mixed phase exists below βc of the coupled network system, where an epidemic occurs in one network but does not spread to the coupled network. We derive an expression for the network and disease parameters that allow this mixed phase and verify it numerically. Public health implications of communities comprising these two classes of network systems are also mentioned.

  8. Network effects in railways

    DEFF Research Database (Denmark)

    Landex, Alex

    2012-01-01

    Railway operation is often affected by network effects as a change in one part of the network can influence other parts of the network. Network effects occur because the train runs may be quite long and since the railway system has a high degree of interdependencies as trains cannot cross....../overtake each other everywhere in the network. First this paper describes network effects in general (section 1). In section 2 the network effects for trains and how they can be measured by scheduled waiting time is described. When the trains are affected by network effects the passengers are also affected....... Therefore, sections 3 and 4 describe the network effects for passengers and how they can be measured using passenger delay models. Before the concluding remarks in section 6, section 5 discusses how the operation can be improved by examining network effects in the planning process. © 2012 WIT Press....

  9. Fundamentals of Stochastic Networks

    CERN Document Server

    Ibe, Oliver C

    2011-01-01

    An interdisciplinary approach to understanding queueing and graphical networks In today's era of interdisciplinary studies and research activities, network models are becoming increasingly important in various areas where they have not regularly been used. Combining techniques from stochastic processes and graph theory to analyze the behavior of networks, Fundamentals of Stochastic Networks provides an interdisciplinary approach by including practical applications of these stochastic networks in various fields of study, from engineering and operations management to communications and the physi

  10. Epidemic Network Failures in Optical Transport Networks

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Katsikas, Dimitrios; Fagertun, Anna Manolova

    2013-01-01

    This paper presents a failure propagation model for transport networks which are affected by epidemic failures. The network is controlled using the GMPLS protocol suite. The Susceptible Infected Disabled (SID) epidemic model is investigated and new signaling functionality of GMPLS to support epid...... epidemic failure resolution is proposed. The results provide important input to service recovery mechanisms under epidemic failures.......This paper presents a failure propagation model for transport networks which are affected by epidemic failures. The network is controlled using the GMPLS protocol suite. The Susceptible Infected Disabled (SID) epidemic model is investigated and new signaling functionality of GMPLS to support...

  11. COMPARISON OF WIRELESS NETWORK OVER WIRED NETWORK AND ITS TYPE

    OpenAIRE

    Shikha Shukla; Meghana K M; Manjunath C R; SantoshNaik

    2017-01-01

    Wireless network has become one of the major requirements in today world. People expect wireless network in home, shopping mall, university etc. Nowadays, we cannot imagine the life without network. In this paper focuses on what the different types of networks are. Why wired network is preferred over wireless network. We will further compare the wired network with the wireless network and also present different type of wireless network. This paper provides the basic knowledge about Wired, Wir...

  12. Computer network defense system

    Science.gov (United States)

    Urias, Vincent; Stout, William M. S.; Loverro, Caleb

    2017-08-22

    A method and apparatus for protecting virtual machines. A computer system creates a copy of a group of the virtual machines in an operating network in a deception network to form a group of cloned virtual machines in the deception network when the group of the virtual machines is accessed by an adversary. The computer system creates an emulation of components from the operating network in the deception network. The components are accessible by the group of the cloned virtual machines as if the group of the cloned virtual machines was in the operating network. The computer system moves network connections for the group of the virtual machines in the operating network used by the adversary from the group of the virtual machines in the operating network to the group of the cloned virtual machines, enabling protecting the group of the virtual machines from actions performed by the adversary.

  13. Morphological neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, G.X.; Sussner, P. [Univ. of Florida, Gainesville, FL (United States)

    1996-12-31

    The theory of artificial neural networks has been successfully applied to a wide variety of pattern recognition problems. In this theory, the first step in computing the next state of a neuron or in performing the next layer neural network computation involves the linear operation of multiplying neural values by their synaptic strengths and adding the results. Thresholding usually follows the linear operation in order to provide for nonlinearity of the network. In this paper we introduce a novel class of neural networks, called morphological neural networks, in which the operations of multiplication and addition are replaced by addition and maximum (or minimum), respectively. By taking the maximum (or minimum) of sums instead of the sum of products, morphological network computation is nonlinear before thresholding. As a consequence, the properties of morphological neural networks are drastically different than those of traditional neural network models. In this paper we consider some of these differences and provide some particular examples of morphological neural network.

  14. Dynamic ad hoc networks

    CERN Document Server

    Rashvand, Habib

    2013-01-01

    Motivated by the exciting new application paradigm of using amalgamated technologies of the Internet and wireless, the next generation communication networks (also called 'ubiquitous', 'complex' and 'unstructured' networking) are changing the way we develop and apply our future systems and services at home and on local, national and global scales. Whatever the interconnection - a WiMAX enabled networked mobile vehicle, MEMS or nanotechnology enabled distributed sensor systems, Vehicular Ad hoc Networking (VANET) or Mobile Ad hoc Networking (MANET) - all can be classified under new networking s

  15. Intelligent networked teleoperation control

    CERN Document Server

    Li, Zhijun; Su, Chun-Yi

    2015-01-01

    This book describes a unified framework for networked teleoperation systems involving multiple research fields: networked control systems for linear and nonlinear forms, bilateral teleoperation, trilateral teleoperation, multilateral teleoperation and cooperative teleoperation. It closely examines networked control as a field at the intersection of systems & control and robotics and presents a number of experimental case studies on testbeds for robotic systems, including networked haptic devices, robotic network systems and sensor network systems. The concepts and results outlined are easy to understand, even for readers fairly new to the subject. As such, the book offers a valuable reference work for researchers and engineers in the fields of systems & control and robotics.

  16. Social network data analytics

    CERN Document Server

    Aggarwal, Charu C

    2011-01-01

    Social network analysis applications have experienced tremendous advances within the last few years due in part to increasing trends towards users interacting with each other on the internet. Social networks are organized as graphs, and the data on social networks takes on the form of massive streams, which are mined for a variety of purposes. Social Network Data Analytics covers an important niche in the social network analytics field. This edited volume, contributed by prominent researchers in this field, presents a wide selection of topics on social network data mining such as Structural Pr

  17. Cisco networking essentials

    CERN Document Server

    McMillan, Troy

    2015-01-01

    Start a career in networking Cisco Networking Essentials, 2nd Edition provides the latest for those beginning a career in networking. This book provides the fundamentals of networking and leads you through the concepts, processes, and skills you need to master fundamental networking concepts. Thinking of taking the CCENT Cisco Certified Entry Networking Technician ICND1 Exam 100-101? This book has you covered! With coverage of important topics and objectives, each chapter outlines main points and provides clear, engaging discussion that will give you a sound understanding of core topics and c

  18. Bufferless transmission in complex networks

    OpenAIRE

    Pu, Cunlai; Cui, Wei; Wu, Jiexin; Yang, Jian

    2017-01-01

    Complex bufferless networks such as on-chip networks and optical burst switching networks haven't been paid enough attention in network science. In complex bufferless networks, the store and forward mechanism is not applicable, since the network nodes are not allowed to buffer data packets. In this paper, we study the data transmission process in complex bufferless networks from the perspective of network science. Specifically, we use the Price model to generate the underlying network topolog...

  19. Do Policy Networks lead to Network Governing?

    DEFF Research Database (Denmark)

    Damgaard, Bodil

    This paper challenges the notion that creation of local policy networks necessarily leads to network governing. Through actor-centred case studies in the area of municipally implemented employment policy in Denmark it was found that the local governing mode is determined mainly by the municipality...

  20. Networks and Networking: The Public Administrative Agendas

    NARCIS (Netherlands)

    O'Toole, Laurence J.

    2014-01-01

    Published in 1997, the article “Treating Networks Seriously: Practical and Research-Based Agendas in Public Administration” outlined the importance of networks for the field of public administration and suggested a series of research agendas that should be pursued. That argument has received

  1. Network biomarkers, interaction networks and dynamical network biomarkers in respiratory diseases

    OpenAIRE

    Wu, Xiaodan; Chen, Luonan; Wang, Xiangdong

    2014-01-01

    Identification and validation of interaction networks and network biomarkers have become more critical and important in the development of disease-specific biomarkers, which are functionally changed during disease development, progression or treatment. The present review headlined the definition, significance, research and potential application for network biomarkers, interaction networks and dynamical network biomarkers (DNB). Disease-specific interaction networks, network biomarkers, or DNB...

  2. Multilayer Social Networks

    DEFF Research Database (Denmark)

    Dickison, Mark; Magnani, Matteo; Rossi, Luca

    Multilayer networks, in particular multilayer social networks, where users belong to and interact on different networks at the same time, are an active research area in social network analysis, computer science, and physics. These networks have traditionally been studied within these separate...... social network systems, the evolution of interconnected social networks, and dynamic processes such as information spreading. A single real dataset is used to illustrate the concepts presented throughout the book, demonstrating both the practical utility and the potential shortcomings of the various...... research communities, leading to the development of several independent models and methods to deal with the same set of problems. This book unifies and consolidates existing practical and theoretical knowledge on multilayer networks including data collection and analysis, modeling, and mining of multilayer...

  3. Networks around entrepreneurs

    DEFF Research Database (Denmark)

    Bertelsen, Rasmus Gjedssø; Ashourizadeh, Shayegheh; Jensen, Kent Wickstrøm

    2017-01-01

    Purpose: Entrepreneurs are networking with others to get advice for their businesses. The networking differs between men and women; notably, men are more often networking in the public sphere and women are more often networking in the private sphere. The aim here is to account for how...... such gendering of entrepreneurs’ networks differ between societies and cultures. Research Design: Based on survey data from the Global Entrepreneurships Monitor, a sample of 16,365 entrepreneurs is used to compare the gendering of entrepreneurs’ networks in China, and five countries largely located around...... the Persian Gulf, namely Yemen, Iran, Saudi Arabia, Qatar and United Arab Emirates. Findings: Analyses show that female entrepreneurs tend to have slightly larger private sphere networks than male entrepreneurs. The differences between male and female entrepreneurs’ networking in the public sphere...

  4. Temporal network epidemiology

    CERN Document Server

    Holme, Petter

    2017-01-01

    This book covers recent developments in epidemic process models and related data on temporally varying networks. It is widely recognized that contact networks are indispensable for describing, understanding, and intervening to stop the spread of infectious diseases in human and animal populations; “network epidemiology” is an umbrella term to describe this research field. More recently, contact networks have been recognized as being highly dynamic. This observation, also supported by an increasing amount of new data, has led to research on temporal networks, a rapidly growing area. Changes in network structure are often informed by epidemic (or other) dynamics, in which case they are referred to as adaptive networks. This volume gathers contributions by prominent authors working in temporal and adaptive network epidemiology, a field essential to understanding infectious diseases in real society.

  5. Multilayer Social Networks

    DEFF Research Database (Denmark)

    Dickison, Mark; Magnani, Matteo; Rossi, Luca

    social network systems, the evolution of interconnected social networks, and dynamic processes such as information spreading. A single real dataset is used to illustrate the concepts presented throughout the book, demonstrating both the practical utility and the potential shortcomings of the various......Multilayer networks, in particular multilayer social networks, where users belong to and interact on different networks at the same time, are an active research area in social network analysis, computer science, and physics. These networks have traditionally been studied within these separate...... research communities, leading to the development of several independent models and methods to deal with the same set of problems. This book unifies and consolidates existing practical and theoretical knowledge on multilayer networks including data collection and analysis, modeling, and mining of multilayer...

  6. Networking for the Environment

    DEFF Research Database (Denmark)

    Dickel, Petra; Hörisch, Jacob; Ritter, Thomas

    2018-01-01

    from 248 technology-based start-ups shows that those firms with a strong external environmental orientation have significantly higher networking frequencies and build larger networks. Conversely, a strong internal environmental orientation is linked to smaller networks. Thus, the results highlight......Although the public debate on the environmental orientation of firms has intensified, there is a lack of understanding about the consequences of that orientation, especially in terms of its impact on firms' networking behavior. In order to fill this gap, this paper analyzes the impact of external...... and internal environmental orientation on start-ups’ network characteristics, because networks are both vital for the success of start-ups and resource demanding. More specifically, the effects of environmental orientation on networking frequency and network size among start-ups are analyzed. Empirical data...

  7. Virtualized Network Control (VNC)

    Energy Technology Data Exchange (ETDEWEB)

    Lehman, Thomas [Univ. of Southern California, Los Angeles, CA (United States); Guok, Chin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ghani, Nasir [Univ. of New Mexico, Albuquerque, NM (United States)

    2013-01-31

    The focus of this project was on the development of a "Network Service Plane" as an abstraction model for the control and provisioning of multi-layer networks. The primary motivation for this work were the requirements of next generation networked applications which will need to access advanced networking as a first class resource at the same level as compute and storage resources. A new class of "Intelligent Network Services" were defined in order to facilitate the integration of advanced network services into application specific workflows. This new class of network services are intended to enable real-time interaction between the application co-scheduling algorithms and the network for the purposes of workflow planning, real-time resource availability identification, scheduling, and provisioning actions.

  8. Wireshark network security

    CERN Document Server

    Verma, Piyush

    2015-01-01

    If you are network administrator or a security analyst with an interest in using Wireshark for security analysis, then this is the book for you. Basic familiarity with common network and application services terms and technologies is assumed.

  9. Energy Sciences Network (ESnet)

    Data.gov (United States)

    Federal Laboratory Consortium — The Energy Sciences Network is the Department of Energy’s high-speed network that provides the high-bandwidth, reliable connections that link scientists at national...

  10. Cooperative Hurricane Network Obs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Observations from the Cooperative Hurricane Reporting Network (CHURN), a special network of stations that provided observations when tropical cyclones approached the...

  11. Adaptive dynamical networks

    Science.gov (United States)

    Maslennikov, O. V.; Nekorkin, V. I.

    2017-10-01

    Dynamical networks are systems of active elements (nodes) interacting with each other through links. Examples are power grids, neural structures, coupled chemical oscillators, and communications networks, all of which are characterized by a networked structure and intrinsic dynamics of their interacting components. If the coupling structure of a dynamical network can change over time due to nodal dynamics, then such a system is called an adaptive dynamical network. The term ‘adaptive’ implies that the coupling topology can be rewired; the term ‘dynamical’ implies the presence of internal node and link dynamics. The main results of research on adaptive dynamical networks are reviewed. Key notions and definitions of the theory of complex networks are given, and major collective effects that emerge in adaptive dynamical networks are described.

  12. Determinants of Network Outcomes

    DEFF Research Database (Denmark)

    Ysa, Tamyko; Sierra, Vicenta; Esteve, Marc

    2014-01-01

    The literature on network management is extensive. However, it generally explores network structures, neglecting the impact of management strategies. In this article we assess the effect of management strategies on network outcomes, providing empirical evidence from 119 urban revitalization...... networks. We go beyond current work by testing a path model for the determinants of network outcomes and considering the interactions between the constructs: management strategies, trust, complexity, and facilitative leadership. Our results suggest that management strategies have a strong effect on network...... outcomes and that they enhance the level of trust. We also found that facilitative leadership has a positive impact on network management as well as on trust in the network. Our findings also show that complexity has a negative impact on trust. A key finding of our research is that managers may wield more...

  13. Bladder Cancer Advocacy Network

    Science.gov (United States)

    ... Grants Bladder Cancer Think Tank Bladder Cancer Research Network Bladder Cancer Genomics Consortium Get Involved Ways to ... us? Who we are The Bladder Cancer Advocacy Network (BCAN) is a community of patients, caregivers, survivors, ...

  14. Congenital Heart Information Network

    Science.gov (United States)

    ... heart defects. Important Notice The Congenital Heart Information Network website is temporarily out of service. Please join ... and Uwe Baemayr for The Congenital Heart Information Network Exempt organization under Section 501(c)3. Copyright © ...

  15. Class network routing

    Science.gov (United States)

    Bhanot, Gyan [Princeton, NJ; Blumrich, Matthias A [Ridgefield, CT; Chen, Dong [Croton On Hudson, NY; Coteus, Paul W [Yorktown Heights, NY; Gara, Alan G [Mount Kisco, NY; Giampapa, Mark E [Irvington, NY; Heidelberger, Philip [Cortlandt Manor, NY; Steinmacher-Burow, Burkhard D [Mount Kisco, NY; Takken, Todd E [Mount Kisco, NY; Vranas, Pavlos M [Bedford Hills, NY

    2009-09-08

    Class network routing is implemented in a network such as a computer network comprising a plurality of parallel compute processors at nodes thereof. Class network routing allows a compute processor to broadcast a message to a range (one or more) of other compute processors in the computer network, such as processors in a column or a row. Normally this type of operation requires a separate message to be sent to each processor. With class network routing pursuant to the invention, a single message is sufficient, which generally reduces the total number of messages in the network as well as the latency to do a broadcast. Class network routing is also applied to dense matrix inversion algorithms on distributed memory parallel supercomputers with hardware class function (multicast) capability. This is achieved by exploiting the fact that the communication patterns of dense matrix inversion can be served by hardware class functions, which results in faster execution times.

  16. National Lymphedema Network

    Science.gov (United States)

    ... 11-14 NLN Lymphedema Awareness Month National Lymphedema Network Lymphedema Overview Start Here! Get an overview of ... activities and goings-on. Follow the National Lymphedema Network newsfeed below. Also, see the following links for ...

  17. Linux Networking Cookbook

    CERN Document Server

    Schroder, Carla

    2008-01-01

    If you want a book that lays out the steps for specific Linux networking tasks, one that clearly explains the commands and configurations, this is the book for you. Linux Networking Cookbook is a soup-to-nuts collection of recipes that covers everything you need to know to perform your job as a Linux network administrator. You'll dive straight into the gnarly hands-on work of building and maintaining a computer network

  18. Social Networking and Health

    OpenAIRE

    Kevin Curran; Michael Mc Hugh

    2013-01-01

    The rise of social networking has revolutionised how people communicate on a daily basis. In a world where more people are connecting to the internet, social networking services create an immediate communication link between users. Social networking sites provide multiple services which include emailing, instant messaging, uploading files, gaming and finding friends. Just as social networking has become a more popular method of communication in recent years, the ways in which people look afte...

  19. Organization Virtual or Networked?

    OpenAIRE

    Rūta Tamošiūnaitė

    2013-01-01

    Purpose—to present distinction between “virtual organization” and “networked organization”; giving their definitions.Design/methodology/approach—review of previous researches, systemic analyses of their findings and synthesis of distinctive characteristics of ”virtual organization” and “networked organization.”Findings—the main result of the research is key diverse features separating ”virtual organization” and ”networked organization.” Definitions of “virtual organization” and “networked org...

  20. Dynamics of social networks

    OpenAIRE

    Ebel, Holger; Davidsen, Joern; Bornholdt, Stefan

    2003-01-01

    Complex networks as the World Wide Web, the web of human sexual contacts or criminal networks often do not have an engineered architecture but instead are self-organized by the actions of a large number of individuals. From these local interactions non-trivial global phenomena can emerge as small-world properties or scale-free degree distributions. A simple model for the evolution of acquaintance networks highlights the essential dynamical ingredients necessary to obtain such complex network ...

  1. Cognitive Dynamic Optical Networks

    DEFF Research Database (Denmark)

    de Miguel, Ignacio; Duran, Ramon J.; Lorenzo, Ruben M.

    2013-01-01

    Cognitive networks are a promising solution for the control of heterogeneous optical networks. We review their fundamentals as well as a number of applications developed in the framework of the EU FP7 CHRON project.......Cognitive networks are a promising solution for the control of heterogeneous optical networks. We review their fundamentals as well as a number of applications developed in the framework of the EU FP7 CHRON project....

  2. On the Performance Evaluation of Query-Based Wireless Sensor Networks

    Science.gov (United States)

    2012-01-01

    Specifically, ∆∞ = P(T̃ > X) = ∫ ∞ 0 P(T̃ > X|In = 0,X = x)P(In = 0)dH(x) = π0 ∫ ∞ 0 e−(1−π0)(µ−λq) xdH (x) = π0 H̃ [(1− π0)(µ − λq)] . Proposition 5...1 is the inverse Laplace transform operator. Finally, we obtain lim r→∞ ∆r = ∫ ∞ 0 π0 e −(1−π0)(µ−λq) xdH (x) = ∫ ∞ 0 P(T̃ > X|In = 0,X = x)π0dH(x) = P

  3. Securing Personal Network Clusters

    NARCIS (Netherlands)

    Jehangir, A.; Heemstra de Groot, S.M.

    2007-01-01

    A Personal Network is a self-organizing, secure and private network of a user’s devices notwithstanding their geographic location. It aims to utilize pervasive computing to provide users with new and improved services. In this paper we propose a model for securing Personal Network clusters. Clusters

  4. Measuring information networks

    Indian Academy of Sciences (India)

    of governance (CEO) defined by company executives in the USA where two CEOs are connected by a link if they are members of the same board [9]. One sees that IS > IS(random) for most networks, except for the fly network. Thus most networks have a topology that tends to hide nodes. In fact this can be quantified.

  5. OSI Network Management.

    Science.gov (United States)

    Harris, Ethan

    1990-01-01

    Management of heterogeneous networks is complicated by the persistence of proprietary management schemes. The need for integration of network management capabilities is pressing. The International Organization for Standardization is developing standards for managing networks as part of the Open Systems Interconnection (OSI) effort. OSI management…

  6. Managing Knowledge Networks.

    Science.gov (United States)

    Contractor, Noshir S.; Monge, Peter R.

    2002-01-01

    Describes a multitheoretical, multilevel (MTML) model to study the management of knowledge networks. Considers theoretical mechanisms for emergence of knowledge networks and presents empirical findings about the emergence of knowledge networks. Concludes that it is necessary to utilize MTML models to integrate multiple social and communication…

  7. Neural Network Ensembles

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Salamon, Peter

    1990-01-01

    We propose several means for improving the performance an training of neural networks for classification. We use crossvalidation as a tool for optimizing network parameters and architecture. We show further that the remaining generalization error can be reduced by invoking ensembles of similar...... networks....

  8. Information network architectures

    Science.gov (United States)

    Murray, N. D.

    1985-01-01

    Graphs, charts, diagrams and outlines of information relative to information network architectures for advanced aerospace missions, such as the Space Station, are presented. Local area information networks are considered a likely technology solution. The principle needs for the network are listed.

  9. Spanish Museum Libraries Network.

    Science.gov (United States)

    Lopez de Prado, Rosario

    This paper describes the creation of an automated network of museum libraries in Spain. The only way in which the specialized libraries in the world today can continue to be active and to offer valid information is to automate the service they offer, and create network libraries with cooperative plans. The network can be configured with different…

  10. Optimal Fragile Financial Networks

    NARCIS (Netherlands)

    Castiglionesi, F.; Navarro, N.

    2007-01-01

    We study a financial network characterized by the presence of depositors, banks and their shareholders. Belonging to a financial network is beneficial for both the depositors and banks' shareholders since the return to investment increases with the number of banks connected. However, the network is

  11. Underwater Acoustic Networking Techniques

    CERN Document Server

    Otnes, Roald; Casari, Paolo; Goetz, Michael; Husøy, Thor; Nissen, Ivor; Rimstad, Knut; van Walree, Paul; Zorzi, Michele

    2012-01-01

    This literature study presents an overview of underwater acoustic networking. It provides a background and describes the state of the art of all networking facets that are relevant for underwater applications. This report serves both as an introduction to the subject and as a summary of existing protocols, providing support and inspiration for the development of network architectures.

  12. Metallic nanowire networks

    Science.gov (United States)

    Song, Yujiang; Shelnutt, John A.

    2012-11-06

    A metallic nanowire network synthesized using chemical reduction of a metal ion source by a reducing agent in the presence of a soft template comprising a tubular inverse micellar network. The network of interconnected polycrystalline nanowires has a very high surface-area/volume ratio, which makes it highly suitable for use in catalytic applications.

  13. The Network Paradox

    National Research Council Canada - National Science Library

    David Rothkopf

    2015-01-01

    .... Call it the "network paradox," a phenomenon by which joining a network can both strengthen and create new vulnerabilities for those on the network. Setting aside hyperbole and simplistic visions is essential when planning for a future that is going to become dramatically different in many complex ways.

  14. Laws of Network Value

    Directory of Open Access Journals (Sweden)

    Juan M.C. Larrosa

    2016-12-01

    Full Text Available The valuation of a social network is an issue that has been addressed based on simplifying approaches. Various value laws have been stipulated, which are largely atheoretical but have been effectively used to estimate the potential economic value of social network-based firms. This review highlights the various contributions used in the recent literature on networks valuation laws.

  15. Networks and Economic Behavior

    OpenAIRE

    Jackson, Matthew O.

    2009-01-01

    Recent analyses of social networks, both empirical and theoretical, are discussed, with a focus on how social networks influence economic behavior, as well as how social networks form. Some challenges of such research are discussed as are some of the important considerations for the future.

  16. Animal transportation networks.

    Science.gov (United States)

    Perna, Andrea; Latty, Tanya

    2014-11-06

    Many group-living animals construct transportation networks of trails, galleries and burrows by modifying the environment to facilitate faster, safer or more efficient movement. Animal transportation networks can have direct influences on the fitness of individuals, whereas the shape and structure of transportation networks can influence community dynamics by facilitating contacts between different individuals and species. In this review, we discuss three key areas in the study of animal transportation networks: the topological properties of networks, network morphogenesis and growth, and the behaviour of network users. We present a brief primer on elements of network theory, and then discuss the different ways in which animal groups deal with the fundamental trade-off between the competing network properties of travel efficiency, robustness and infrastructure cost. We consider how the behaviour of network users can impact network efficiency, and call for studies that integrate both network topology and user behaviour. We finish with a prospectus for future research. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  17. Heterogeneous network architectures

    DEFF Research Database (Denmark)

    Christiansen, Henrik Lehrmann

    2006-01-01

    Future networks will be heterogeneous! Due to the sheer size of networks (e.g., the Internet) upgrades cannot be instantaneous and thus heterogeneity appears. This means that instead of trying to find the olution, networks hould be designed as being heterogeneous. One of the key equirements here...

  18. Synchronization of networks

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... We study the synchronization of coupled dynamical systems on networks. The dynamics is governed by a local nonlinear oscillator for each node of the network and interactions connecting different nodes via the links of the network. We consider existence and stability conditions for both single- and ...

  19. Network Descriptions and NEC

    NARCIS (Netherlands)

    Keus, H.E.; Ham, J.J. van der; Daal, M. van; Laat, C. de

    2008-01-01

    The network is one of the most important components of NEC. In order to achieve high levels of agility and flexibility it is important that all users and providers have a good overview of the capabilities and possibilities of the network. Historically network applications have used their own

  20. Is the immune network a complex network?

    CERN Document Server

    Souza-e-Silva, Hallan

    2012-01-01

    Some years ago a cellular automata model was proposed to describe the evolution of the immune repertoire of B cells and antibodies based on Jerne's immune network theory and shape-space formalism. Here we investigate if the networks generated by this model in the different regimes can be classified as complex networks. We have found that in the chaotic regime the network has random characteristics with large, constant values of clustering coefficients, while in the ordered phase, the degree distribution of the network is exponential and the clustering coefficient exhibits power law behavior. In the transition region we observed a mixed behavior (random-like and exponential) of the degree distribution as opposed to the scale-free behavior reported for other biological networks. Randomness and low connectivity in the active sites allow for rapid changes in the connectivity distribution of the immune network in order to include and/or discard information and generate a dynamic memory. However it is the availabil...

  1. Localizing and placement of network node functions in a network

    NARCIS (Netherlands)

    Strijkers, R.J.; Meulenhoff, P.J.

    2014-01-01

    The invention enables placement and use of a network node function in a second network node instead of using the network node function in a first network node. The network node function is e.g. a server function or a router function. The second network node is typically located in or close to the

  2. Biometrics for home networks security

    KAUST Repository

    Ansari, Imran Shafique

    2009-01-01

    Hacking crimes committed to the home networks are increasing. Advanced network protection is not always possible for the home networks. In this paper we will study the ability of using biometric systems for authentication in home networks. ©2009 IEEE.

  3. Dominating biological networks.

    Directory of Open Access Journals (Sweden)

    Tijana Milenković

    Full Text Available Proteins are essential macromolecules of life that carry out most cellular processes. Since proteins aggregate to perform function, and since protein-protein interaction (PPI networks model these aggregations, one would expect to uncover new biology from PPI network topology. Hence, using PPI networks to predict protein function and role of protein pathways in disease has received attention. A debate remains open about whether network properties of "biologically central (BC" genes (i.e., their protein products, such as those involved in aging, cancer, infectious diseases, or signaling and drug-targeted pathways, exhibit some topological centrality compared to the rest of the proteins in the human PPI network.To help resolve this debate, we design new network-based approaches and apply them to get new insight into biological function and disease. We hypothesize that BC genes have a topologically central (TC role in the human PPI network. We propose two different concepts of topological centrality. We design a new centrality measure to capture complex wirings of proteins in the network that identifies as TC those proteins that reside in dense extended network neighborhoods. Also, we use the notion of domination and find dominating sets (DSs in the PPI network, i.e., sets of proteins such that every protein is either in the DS or is a neighbor of the DS. Clearly, a DS has a TC role, as it enables efficient communication between different network parts. We find statistically significant enrichment in BC genes of TC nodes and outperform the existing methods indicating that genes involved in key biological processes occupy topologically complex and dense regions of the network and correspond to its "spine" that connects all other network parts and can thus pass cellular signals efficiently throughout the network. To our knowledge, this is the first study that explores domination in the context of PPI networks.

  4. Robustness of weighted networks

    Science.gov (United States)

    Bellingeri, Michele; Cassi, Davide

    2018-01-01

    Complex network response to node loss is a central question in different fields of network science because node failure can cause the fragmentation of the network, thus compromising the system functioning. Previous studies considered binary networks where the intensity (weight) of the links is not accounted for, i.e. a link is either present or absent. However, in real-world networks the weights of connections, and thus their importance for network functioning, can be widely different. Here, we analyzed the response of real-world and model networks to node loss accounting for link intensity and the weighted structure of the network. We used both classic binary node properties and network functioning measure, introduced a weighted rank for node importance (node strength), and used a measure for network functioning that accounts for the weight of the links (weighted efficiency). We find that: (i) the efficiency of the attack strategies changed using binary or weighted network functioning measures, both for real-world or model networks; (ii) in some cases, removing nodes according to weighted rank produced the highest damage when functioning was measured by the weighted efficiency; (iii) adopting weighted measure for the network damage changed the efficacy of the attack strategy with respect the binary analyses. Our results show that if the weighted structure of complex networks is not taken into account, this may produce misleading models to forecast the system response to node failure, i.e. consider binary links may not unveil the real damage induced in the system. Last, once weighted measures are introduced, in order to discover the best attack strategy, it is important to analyze the network response to node loss using nodes rank accounting the intensity of the links to the node.

  5. Managing Innovation Networks

    DEFF Research Database (Denmark)

    Awate, Snehal Suyash; Møller Larsen, Marcus; Mudambi, Ram

    In this article, we treat innovation as a multidimensional construct spanning people, technologies, and geographies. We study how these dimensions interact and impact firms' inventor networks and the ultimate innovation performance. We identify five distinct planes in which inventor networks reside...... of the costs and benefits of being centrally located on multiplex network versus having an equal distribution of ties between the different network layers. Using patent data on the global wind power industry, we find evidence suggesting that being centrally positioned on a multiplex network with an equal...

  6. Networks Technology Conference

    Science.gov (United States)

    Tasaki, Keiji K. (Editor)

    1993-01-01

    The papers included in these proceedings represent the most interesting and current topics being pursued by personnel at GSFC's Networks Division and supporting contractors involved in Space, Ground, and Deep Space Network (DSN) technical work. Although 29 papers are represented in the proceedings, only 12 were presented at the conference because of space and time limitations. The proceedings are organized according to five principal technical areas of interest to the Networks Division: Project Management; Network Operations; Network Control, Scheduling, and Monitoring; Modeling and Simulation; and Telecommunications Engineering.

  7. Learning conditional Gaussian networks

    DEFF Research Database (Denmark)

    Bøttcher, Susanne Gammelgaard

    This paper considers conditional Gaussian networks. The parameters in the network are learned by using conjugate Bayesian analysis. As conjugate local priors, we apply the Dirichlet distribution for discrete variables and the Gaussian-inverse gamma distribution for continuous variables, given...... a configuration of the discrete parents. We assume parameter independence and complete data. Further, to learn the structure of the network, the network score is deduced. We then develop a local master prior procedure, for deriving parameter priors in these networks. This procedure satisfies parameter...... independence, parameter modularity and likelihood equivalence. Bayes factors to be used in model search are introduced. Finally the methods derived are illustrated by a simple example....

  8. NASA's unique networking environment

    Science.gov (United States)

    Johnson, Marjory J.

    1988-01-01

    Networking is an infrastructure technology; it is a tool for NASA to support its space and aeronautics missions. Some of NASA's networking problems are shared by the commercial and/or military communities, and can be solved by working with these communities. However, some of NASA's networking problems are unique and will not be addressed by these other communities. Individual characteristics of NASA's space-mission networking enviroment are examined, the combination of all these characteristics that distinguish NASA's networking systems from either commercial or military systems is explained, and some research areas that are important for NASA to pursue are outlined.

  9. Computer-communication networks

    CERN Document Server

    Meditch, James S

    1983-01-01

    Computer- Communication Networks presents a collection of articles the focus of which is on the field of modeling, analysis, design, and performance optimization. It discusses the problem of modeling the performance of local area networks under file transfer. It addresses the design of multi-hop, mobile-user radio networks. Some of the topics covered in the book are the distributed packet switching queuing network design, some investigations on communication switching techniques in computer networks and the minimum hop flow assignment and routing subject to an average message delay constraint

  10. Microsoft Windows networking essentials

    CERN Document Server

    Gibson, Darril

    2011-01-01

    The core concepts and technologies of Windows networking Networking can be a complex topic, especially for those new to the field of IT. This focused, full-color book takes a unique approach to teaching Windows networking to beginners by stripping down a network to its bare basics, thereby making each topic clear and easy to understand. Focusing on the new Microsoft Technology Associate (MTA) program, this book pares down to just the essentials, showing beginners how to gain a solid foundation for understanding networking concepts upon which more advanced topics and technologies can be built.

  11. Networks in Cognitive Science

    CERN Document Server

    Baronchelli, Andrea; Pastor-Satorras, Romualdo; Chater, Nick; Christiansen, Morten H

    2013-01-01

    Networks of interconnected nodes have long played a key role in cognitive science, from artificial neural networks to spreading activation models of semantic memory. Recently, however, a new Network Science has been developed, providing insights into the emergence of global, system-scale properties in contexts as diverse as the Internet, metabolic reactions or collaborations among scientists. Today, the inclusion of network theory into cognitive sciences, and the expansion of complex systems science, promises to significantly change the way in which the organization and dynamics of cognitive and behavioral processes are understood. In this paper, we review recent contributions of network theory at different levels and domains within the cognitive sciences.

  12. Cisco Networking Essentials

    CERN Document Server

    McMillan, Troy

    2011-01-01

    An engaging approach for anyone beginning a career in networking As the world leader of networking products and services, Cisco products are constantly growing in demand. Yet, few books are aimed at those who are beginning a career in IT--until now. Cisco Networking Essentials provides a solid foundation on the Cisco networking products and services with thorough coverage of fundamental networking concepts. Author Troy McMillan applies his years of classroom instruction to effectively present high-level topics in easy-to-understand terms for beginners. With this indispensable full-color resour

  13. Manufacturing network evolution

    DEFF Research Database (Denmark)

    Yang, Cheng; Farooq, Sami; Johansen, John

    2011-01-01

    Purpose – This paper examines the effect of changes at the manufacturing plant level on other plants in the manufacturing network and also investigates the role of manufacturing plants on the evolution of a manufacturing network. Design/methodology/approach –The research questions are developed......, the complex phenomenon of a manufacturing network evolution is observed by combining the analysis of a manufacturing plant and network level. The historical trajectories of manufacturing networks that are presented in the case studies are examined in order to understand and determine the future shape...

  14. Wireless mesh networks

    CERN Document Server

    Held, Gilbert

    2005-01-01

    Wireless mesh networking is a new technology that has the potential to revolutionize how we access the Internet and communicate with co-workers and friends. Wireless Mesh Networks examines the concept and explores its advantages over existing technologies. This book explores existing and future applications, and examines how some of the networking protocols operate.The text offers a detailed analysis of the significant problems affecting wireless mesh networking, including network scale issues, security, and radio frequency interference, and suggests actual and potential solutions for each pro

  15. Innovation and network collaboration

    DEFF Research Database (Denmark)

    Kesting, Peter; Müller, Sabine; Jørgensen, Frances

    2011-01-01

    Research suggests that small and medium-sized enterprises (SMEs) can benefit from network collaboration by enhancing opportunities for innovation. Managing the necessary collaboration to benefit from network participation may however be particularly challenging for SMEs due to their size...... and their inherent shortage of resources. In this paper, we propose that human resource management (HRM) practices may provide a means by which SMEs can increase their innovation capacity through network collaboration. Following a brief presentation of the relevant literature on networks, and innovation in networks...

  16. Network structure of production

    Science.gov (United States)

    Atalay, Enghin; Hortaçsu, Ali; Roberts, James; Syverson, Chad

    2011-01-01

    Complex social networks have received increasing attention from researchers. Recent work has focused on mechanisms that produce scale-free networks. We theoretically and empirically characterize the buyer–supplier network of the US economy and find that purely scale-free models have trouble matching key attributes of the network. We construct an alternative model that incorporates realistic features of firms’ buyer–supplier relationships and estimate the model’s parameters using microdata on firms’ self-reported customers. This alternative framework is better able to match the attributes of the actual economic network and aids in further understanding several important economic phenomena. PMID:21402924

  17. Emergent complex network geometry.

    Science.gov (United States)

    Wu, Zhihao; Menichetti, Giulia; Rahmede, Christoph; Bianconi, Ginestra

    2015-05-18

    Networks are mathematical structures that are universally used to describe a large variety of complex systems such as the brain or the Internet. Characterizing the geometrical properties of these networks has become increasingly relevant for routing problems, inference and data mining. In real growing networks, topological, structural and geometrical properties emerge spontaneously from their dynamical rules. Nevertheless we still miss a model in which networks develop an emergent complex geometry. Here we show that a single two parameter network model, the growing geometrical network, can generate complex network geometries with non-trivial distribution of curvatures, combining exponential growth and small-world properties with finite spectral dimensionality. In one limit, the non-equilibrium dynamical rules of these networks can generate scale-free networks with clustering and communities, in another limit planar random geometries with non-trivial modularity. Finally we find that these properties of the geometrical growing networks are present in a large set of real networks describing biological, social and technological systems.

  18. Fulcrum Network Codes

    DEFF Research Database (Denmark)

    2015-01-01

    Fulcrum network codes, which are a network coding framework, achieve three objectives: (i) to reduce the overhead per coded packet to almost 1 bit per source packet; (ii) to operate the network using only low field size operations at intermediate nodes, dramatically reducing complexity...... in the network; and (iii) to deliver an end-to-end performance that is close to that of a high field size network coding system for high-end receivers while simultaneously catering to low-end ones that can only decode in a lower field size. Sources may encode using a high field size expansion to increase...... the number of dimensions seen by the network using a linear mapping. Receivers can tradeoff computational effort with network delay, decoding in the high field size, the low field size, or a combination thereof....

  19. Network topology analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Kalb, Jeffrey L.; Lee, David S.

    2008-01-01

    Emerging high-bandwidth, low-latency network technology has made network-based architectures both feasible and potentially desirable for use in satellite payload architectures. The selection of network topology is a critical component when developing these multi-node or multi-point architectures. This study examines network topologies and their effect on overall network performance. Numerous topologies were reviewed against a number of performance, reliability, and cost metrics. This document identifies a handful of good network topologies for satellite applications and the metrics used to justify them as such. Since often multiple topologies will meet the requirements of the satellite payload architecture under development, the choice of network topology is not easy, and in the end the choice of topology is influenced by both the design characteristics and requirements of the overall system and the experience of the developer.

  20. Internet protocol network mapper

    Science.gov (United States)

    Youd, David W.; Colon III, Domingo R.; Seidl, Edward T.

    2016-02-23

    A network mapper for performing tasks on targets is provided. The mapper generates a map of a network that specifies the overall configuration of the network. The mapper inputs a procedure that defines how the network is to be mapped. The procedure specifies what, when, and in what order the tasks are to be performed. Each task specifies processing that is to be performed for a target to produce results. The procedure may also specify input parameters for a task. The mapper inputs initial targets that specify a range of network addresses to be mapped. The mapper maps the network by, for each target, executing the procedure to perform the tasks on the target. The results of the tasks represent the mapping of the network defined by the initial targets.

  1. Networks in ATLAS

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00260714; The ATLAS collaboration

    2017-01-01

    Networks have played a critical role in high-energy physics (HEP), enabling us to access and effectively utilize globally distributed resources to meet the needs of our physicists. Because of their importance in enabling our grid computing infrastructure many physicists have taken leading roles in research and education (R&E) networking, participating in, and even convening, network related meetings and research programs with the broader networking community worldwide. This has led to HEP benefiting from excellent global networking capabilities for little to no direct cost. However, as other science domains ramp-up their need for similar networking it becomes less clear that this situation will continue unchanged. What this means for ATLAS in particular needs to be understood. ATLAS has evolved its computing model since the LHC started based upon its experience with using globally distributed resources. The most significant theme of those changes has been increased reliance upon, and use of, its networks....

  2. Networks in ATLAS

    CERN Document Server

    Mc Kee, Shawn Patrick; The ATLAS collaboration

    2016-01-01

    Networks have played a critical role in high-energy physics (HEP), enabling us to access and effectively utilize globally distributed resources to meet the needs of our physicists. Because of their importance in enabling our grid computing infrastructure many physicists have taken leading roles in research and education (R&E) networking, participating in, and even convening, network related meetings and research programs with the broader networking community worldwide. This has led to HEP benefiting from excellent global networking capabilities for little to no direct cost. However, as other science domains ramp-up their need for similar networking it becomes less clear that this situation will continue unchanged. What this means for ATLAS in particular needs to be understood. ATLAS has evolved its computing model since the LHC started based upon its experience with using globally distributed resources. The most significant theme of those changes has been increased reliance upon, and use of, its networks....

  3. Cognitive Dynamic Optical Networks

    DEFF Research Database (Denmark)

    de Miguel, Ignacio; Duran, Ramon J.; Jimenez, Tamara

    2013-01-01

    The use of cognition is a promising element for the control of heterogeneous optical networks. Not only are cognitive networks able to sense current network conditions and act according to them, but they also take into account the knowledge acquired through past experiences; that is, they include...... learning with the aim of improving performance. In this paper, we review the fundamentals of cognitive networks and focus on their application to the optical networking area. In particular, a number of cognitive network architectures proposed so far, as well as their associated supporting technologies......, are reviewed. Moreover, several applications, mainly developed in the framework of the EU FP7 Cognitive Heterogeneous Reconfigurable Optical Network (CHRON) project, are also described....

  4. Organization of complex networks

    Science.gov (United States)

    Kitsak, Maksim

    Many large complex systems can be successfully analyzed using the language of graphs and networks. Interactions between the objects in a network are treated as links connecting nodes. This approach to understanding the structure of networks is an important step toward understanding the way corresponding complex systems function. Using the tools of statistical physics, we analyze the structure of networks as they are found in complex systems such as the Internet, the World Wide Web, and numerous industrial and social networks. In the first chapter we apply the concept of self-similarity to the study of transport properties in complex networks. Self-similar or fractal networks, unlike non-fractal networks, exhibit similarity on a range of scales. We find that these fractal networks have transport properties that differ from those of non-fractal networks. In non-fractal networks, transport flows primarily through the hubs. In fractal networks, the self-similar structure requires any transport to also flow through nodes that have only a few connections. We also study, in models and in real networks, the crossover from fractal to non-fractal networks that occurs when a small number of random interactions are added by means of scaling techniques. In the second chapter we use k-core techniques to study dynamic processes in networks. The k-core of a network is the network's largest component that, within itself, exhibits all nodes with at least k connections. We use this k-core analysis to estimate the relative leadership positions of firms in the Life Science (LS) and Information and Communication Technology (ICT) sectors of industry. We study the differences in the k-core structure between the LS and the ICT sectors. We find that the lead segment (highest k-core) of the LS sector, unlike that of the ICT sector, is remarkably stable over time: once a particular firm enters the lead segment, it is likely to remain there for many years. In the third chapter we study how

  5. Cloud networking understanding cloud-based data center networks

    CERN Document Server

    Lee, Gary

    2014-01-01

    Cloud Networking: Understanding Cloud-Based Data Center Networks explains the evolution of established networking technologies into distributed, cloud-based networks. Starting with an overview of cloud technologies, the book explains how cloud data center networks leverage distributed systems for network virtualization, storage networking, and software-defined networking. The author offers insider perspective to key components that make a cloud network possible such as switch fabric technology and data center networking standards. The final chapters look ahead to developments in architectures

  6. Optical Access Networks

    Science.gov (United States)

    Zheng, Jun; Ansari, Nirwan

    2005-06-01

    Call for Papers: Optical Access Networks With the wide deployment of fiber-optic technology over the past two decades, we have witnessed a tremendous growth of bandwidth capacity in the backbone networks of today's telecommunications infrastructure. However, access networks, which cover the "last-mile" areas and serve numerous residential and small business users, have not been scaled up commensurately. The local subscriber lines for telephone and cable television are still using twisted pairs and coaxial cables. Most residential connections to the Internet are still through dial-up modems operating at a low speed on twisted pairs. As the demand for access bandwidth increases with emerging high-bandwidth applications, such as distance learning, high-definition television (HDTV), and video on demand (VoD), the last-mile access networks have become a bandwidth bottleneck in today's telecommunications infrastructure. To ease this bottleneck, it is imperative to provide sufficient bandwidth capacity in the access networks to open the bottleneck and thus present more opportunities for the provisioning of multiservices. Optical access solutions promise huge bandwidth to service providers and low-cost high-bandwidth services to end users and are therefore widely considered the technology of choice for next-generation access networks. To realize the vision of optical access networks, however, many key issues still need to be addressed, such as network architectures, signaling protocols, and implementation standards. The major challenges lie in the fact that an optical solution must be not only robust, scalable, and flexible, but also implemented at a low cost comparable to that of existing access solutions in order to increase the economic viability of many potential high-bandwidth applications. In recent years, optical access networks have been receiving tremendous attention from both academia and industry. A large number of research activities have been carried out or

  7. Symmetry in Complex Networks

    Directory of Open Access Journals (Sweden)

    Angel Garrido

    2011-01-01

    Full Text Available In this paper, we analyze a few interrelated concepts about graphs, such as their degree, entropy, or their symmetry/asymmetry levels. These concepts prove useful in the study of different types of Systems, and particularly, in the analysis of Complex Networks. A System can be defined as any set of components functioning together as a whole. A systemic point of view allows us to isolate a part of the world, and so, we can focus on those aspects that interact more closely than others. Network Science analyzes the interconnections among diverse networks from different domains: physics, engineering, biology, semantics, and so on. Current developments in the quantitative analysis of Complex Networks, based on graph theory, have been rapidly translated to studies of brain network organization. The brain's systems have complex network features—such as the small-world topology, highly connected hubs and modularity. These networks are not random. The topology of many different networks shows striking similarities, such as the scale-free structure, with the degree distribution following a Power Law. How can very different systems have the same underlying topological features? Modeling and characterizing these networks, looking for their governing laws, are the current lines of research. So, we will dedicate this Special Issue paper to show measures of symmetry in Complex Networks, and highlight their close relation with measures of information and entropy.

  8. Multilayer Brain Networks

    Science.gov (United States)

    Vaiana, Michael; Muldoon, Sarah Feldt

    2018-01-01

    The field of neuroscience is facing an unprecedented expanse in the volume and diversity of available data. Traditionally, network models have provided key insights into the structure and function of the brain. With the advent of big data in neuroscience, both more sophisticated models capable of characterizing the increasing complexity of the data and novel methods of quantitative analysis are needed. Recently, multilayer networks, a mathematical extension of traditional networks, have gained increasing popularity in neuroscience due to their ability to capture the full information of multi-model, multi-scale, spatiotemporal data sets. Here, we review multilayer networks and their applications in neuroscience, showing how incorporating the multilayer framework into network neuroscience analysis has uncovered previously hidden features of brain networks. We specifically highlight the use of multilayer networks to model disease, structure-function relationships, network evolution, and link multi-scale data. Finally, we close with a discussion of promising new directions of multilayer network neuroscience research and propose a modified definition of multilayer networks designed to unite and clarify the use of the multilayer formalism in describing real-world systems.

  9. Serial Network Flow Monitor

    Science.gov (United States)

    Robinson, Julie A.; Tate-Brown, Judy M.

    2009-01-01

    Using a commercial software CD and minimal up-mass, SNFM monitors the Payload local area network (LAN) to analyze and troubleshoot LAN data traffic. Validating LAN traffic models may allow for faster and more reliable computer networks to sustain systems and science on future space missions. Research Summary: This experiment studies the function of the computer network onboard the ISS. On-orbit packet statistics are captured and used to validate ground based medium rate data link models and enhance the way that the local area network (LAN) is monitored. This information will allow monitoring and improvement in the data transfer capabilities of on-orbit computer networks. The Serial Network Flow Monitor (SNFM) experiment attempts to characterize the network equivalent of traffic jams on board ISS. The SNFM team is able to specifically target historical problem areas including the SAMS (Space Acceleration Measurement System) communication issues, data transmissions from the ISS to the ground teams, and multiple users on the network at the same time. By looking at how various users interact with each other on the network, conflicts can be identified and work can begin on solutions. SNFM is comprised of a commercial off the shelf software package that monitors packet traffic through the payload Ethernet LANs (local area networks) on board ISS.

  10. Local dependency in networks

    Directory of Open Access Journals (Sweden)

    Kudĕlka Miloš

    2015-06-01

    Full Text Available Many real world data and processes have a network structure and can usefully be represented as graphs. Network analysis focuses on the relations among the nodes exploring the properties of each network. We introduce a method for measuring the strength of the relationship between two nodes of a network and for their ranking. This method is applicable to all kinds of networks, including directed and weighted networks. The approach extracts dependency relations among the network’s nodes from the structure in local surroundings of individual nodes. For the tasks we deal with in this article, the key technical parameter is locality. Since only the surroundings of the examined nodes are used in computations, there is no need to analyze the entire network. This allows the application of our approach in the area of large-scale networks. We present several experiments using small networks as well as large-scale artificial and real world networks. The results of the experiments show high effectiveness due to the locality of our approach and also high quality node ranking comparable to PageRank.

  11. Collaborative learning in networks.

    Science.gov (United States)

    Mason, Winter; Watts, Duncan J

    2012-01-17

    Complex problems in science, business, and engineering typically require some tradeoff between exploitation of known solutions and exploration for novel ones, where, in many cases, information about known solutions can also disseminate among individual problem solvers through formal or informal networks. Prior research on complex problem solving by collectives has found the counterintuitive result that inefficient networks, meaning networks that disseminate information relatively slowly, can perform better than efficient networks for problems that require extended exploration. In this paper, we report on a series of 256 Web-based experiments in which groups of 16 individuals collectively solved a complex problem and shared information through different communication networks. As expected, we found that collective exploration improved average success over independent exploration because good solutions could diffuse through the network. In contrast to prior work, however, we found that efficient networks outperformed inefficient networks, even in a problem space with qualitative properties thought to favor inefficient networks. We explain this result in terms of individual-level explore-exploit decisions, which we find were influenced by the network structure as well as by strategic considerations and the relative payoff between maxima. We conclude by discussing implications for real-world problem solving and possible extensions.

  12. VizieR Online Data Catalog: Mira stars discovered in LAMOST DR4 (Yao+, 2017)

    Science.gov (United States)

    Yao, Y.; Liu, C.; Deng, L.; de Grijs, R.; Matsunaga, N.

    2017-10-01

    By the end of 2016 March, the wide-field Large sky Area Multi-Object fiber Spectroscopic Telescope (LAMOST) DR4 catalog had accumulated 7681185 spectra (R=1800), of which 6898298 were of stars. We compiled a photometrically confirmed sample of Mira variables from the Kiso Wide-Field Camera (KWFC) Intensive Survey of the Galactic Plane (KISOGP; Matsunaga 2017, arXiv:1705.08567), the American Association of Variable Star Observers (AAVSO) International Database Variable Star Index (VSX; Watson 2006, B/vsx, version 2017-05-02; we selected stars of variability type "M"), and the SIMBAD Astronomical Database. We first cross-matched the KISOGP and VSX Miras with the LAMOST DR4 catalog. Finally, we cross-matched the DR4 catalog with the SIMBAD database. See section 2. (1 data file).

  13. Caractérisation hydrochimique de la nappe de Yao et ses environs ...

    African Journals Online (AJOL)

    relations entre eaux de surface (lac-Fitri) et eaux souterraines. Bichara LOUKMAN1*, Samuel NAKOLENDOUSSE1, Abdallah MAHAMAT NOUR2 and MberdoumNGUINAMBAYE MEMTI2. 1Laboratoire GEORESSOURCES, Unité de Formation et de Recherche/ Sciences de la Vie et de la Terre. Université Ouaga1 Pr.

  14. Processes affecting the spatial distribution of seagrass meadow sedimentary material on Yao Yai Island, Thailand

    NARCIS (Netherlands)

    Quak, M.S.Y.; Ziegler, A.D.; Benner, S.G.; Evans, S.; Todd, P.A.; Gillis, L.G.; Vongtanaboon, S.; Jachowski, N.; Bouma, T.J.

    2016-01-01

    Many islands throughout SE Asia are experiencing rapid development and land-cover conversion thatpotentially threaten sensitive coastal ecosystems, such as seagrasses, through increased loading ofsediment and nutrients originating from disturbed catchments draining to the sea. To evaluate this

  15. New Perspectives on Chinese Herbal Medicine (Zhong-Yao Research and Development

    Directory of Open Access Journals (Sweden)

    Si-Yuan Pan

    2011-01-01

    Full Text Available Synthetic chemical drugs, while being efficacious in the clinical management of many diseases, are often associated with undesirable side effects in patients. It is now clear that the need of therapeutic intervention in many clinical conditions cannot be satisfactorily met by synthetic chemical drugs. Since the research and development of new chemical drugs remain time-consuming, capital-intensive and risky, much effort has been put in the search for alternative routes for drug discovery in China. This narrative review illustrates various approaches to the research and drug discovery in Chinese herbal medicine. Although this article focuses on Chinese traditional drugs, it is also conducive to the development of other traditional remedies and innovative drug discovery.

  16. Yao et al., Afr J Tradit Complement Altern Med. (2014) 11(1):222-227

    African Journals Online (AJOL)

    cadewumi

    The treatment lasted for 56, days. The high-fat diet used in the present study includes 25% lard, 2%, cholesterol 0.5%, sodium cholate, and 25%, Tween-80. The hepatic levels of superoxide dismutase (SOD), and malondialdehyde (MDA); the serum levels of total cholesterol (TC), and low-density lipoprotein cholesterol.

  17. 1723-IJBCS-Article- Akoua Kouassi Yao Philomène

    African Journals Online (AJOL)

    hp

    Zepernick & Timber est très utilisé dans de nombreux maux comme vermifuge, frotte dents antiseptique, aphrodisiaque (Adjanohoun, 1986 ; Chaaib et al., 2003; Adesina, 2005 ; Queiroz et al.,. 2006). Cette plante s'est révélée également efficace contre la drépanocytose, les douleurs dentaires, l'angine, les hémorroïdes.

  18. [Investigation on the infection of Blastocystis hominis in populations in Bama Yao Autonomous County of Guangxi].

    Science.gov (United States)

    He, Shan-Shan; Wu, Ling-Yuan; Liu, Xiao-Quan; Shi, Huan-Huan; Chen, Zhi; Zhang, Hui; Pang, Cai-Ying; Li, Yu-Mei

    2013-02-01

    497 fecal specimens were collected from 5 randomly selected villages of Bama County in December 2011, and tested for Blastocystis hominis infection using improved centrifugal sedimentation with hydrochloric acid-ether. Data were analyzed by villages, gender, occupation, age groups and ethnic populations. The results showed that 215 people of 497 were positive, with a prevalence of 43.3% (215/497). Pandang village had the highest infection rate of 55.7% (68/122), significantly higher than the other villages (P0.05).

  19. Evaluation of the Abidjan lagoon pollution BRITON BI, G H; *YAO, B ...

    African Journals Online (AJOL)

    MICHAEL

    Those are finally driven in the urban lakes and lagoons. In addition, the conjugation of the failure of the systems of cleansing and the strong demographic growth of these cities involve strong pressures on these lakes by the polluted runoffs that flow there. The town of Abidjan, one of the most modern metropolises west Africa ...

  20. Evaluation of the Abidjan lagoon pollution BRITON BI, G H; *YAO, B ...

    African Journals Online (AJOL)

    MICHAEL

    Water pollution is a major problem in the great agglomerations in general and African in particular. Because of relatively lenient legislations, industries reject without .... values would be due to the use of detergents for scrubbing. These values could have a negative impact on the life of the watery species and would on the.

  1. Caractérisation hydrochimique de la nappe de Yao et ses environs ...

    African Journals Online (AJOL)

    approvisionnement en eau potable de la population du département de Fitri. Dans cette zone, aucune étude hydrochimique significative des eaux souterraines n'a été entreprise. C'est pourquoi, cette étude s'est fixée pour objectif principal de faire l'état de la ...

  2. Sensor Network Motes:

    DEFF Research Database (Denmark)

    Leopold, Martin

    . In addition, we present our results from porting the highly popular sensor network operating system TinyOS to a new and emerging system on a chip based platform. Moving the sensor network field towards the use of system-on- a-chip devices has large potential in terms of price and performance. We claim to have......This dissertation describes our efforts to improve sensor network performance evaluation and portability, within the context of the sensor network project Hogthrob. In Hogthrob, we faced the challenge of building an sensor network architecture for sow monitoring. This application has hard...... requirements on price and performance, and shows great potential for using sensor networks. Throughout the project we let the application requirements guide our design choices, leading us to push the technologies further to meet the specific goal of the application. In this dissertation, we attack two key...

  3. Liner Service Network Design

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard

    This thesis concerns design of liner shipping networks using operations research to optimize liner shipping networks at the strategic, tactical and operational level. Liner shipping networks are often compared to public transit networks as they consist of a set of scheduled sailings connecting....... The research field of liner shipping network design is relatively young and many open research questions exists. Among others, a unified and rich mathematical model formulating the main characteristics of the business domain has not been clearly described and exact methods for such mathematical models...... are still not able to solve significant instances of this complex optimization problem. In this thesis two research directions are explored within the field: The first research direction contributes to basic research on the liner shipping network design problem by describing the domain seen from...

  4. Green heterogeneous wireless networks

    CERN Document Server

    Ismail, Muhammad; Nee, Hans-Peter; Qaraqe, Khalid A; Serpedin, Erchin

    2016-01-01

    This book focuses on the emerging research topic "green (energy efficient) wireless networks" which has drawn huge attention recently from both academia and industry. This topic is highly motivated due to important environmental, financial, and quality-of-experience (QoE) considerations. Specifically, the high energy consumption of the wireless networks manifests in approximately 2% of all CO2 emissions worldwide. This book presents the authors’ visions and solutions for deployment of energy efficient (green) heterogeneous wireless communication networks. The book consists of three major parts. The first part provides an introduction to the "green networks" concept, the second part targets the green multi-homing resource allocation problem, and the third chapter presents a novel deployment of device-to-device (D2D) communications and its successful integration in Heterogeneous Networks (HetNets). The book is novel in that it specifically targets green networking in a heterogeneous wireless medium, which re...

  5. Managing Interorganizational Networks

    DEFF Research Database (Denmark)

    Gustafsson, Jeppe

    bold enough to predict that networks will become the dominant organisation form in future. Several authors maintain that the shift from traditional hierarchical structures to networks involves dramatic changes for managers and employees (Champy 2002, Rohlin 1994, Kanter 2002). This article seeks...... to isolate some of the forthcoming changes and outlines a map for network management. We will try to avoid summarising the increasingly extensive literature about organisations which are characterised by networks and restrict our focus to management in inter-organisational networks. Inter......Management literature’s many descriptions of the current and future challenges and new trends within organisation and management forms depict a motley and kaleidoscopic picture of the future. However, one idea reoccurs throughout most of the literature – the organisational network. Some are even...

  6. Software Defined Networking

    DEFF Research Database (Denmark)

    Caba, Cosmin Marius

    resources are limited. Hence, to counteract this trend, current QoS mechanisms must become simpler to deploy and operate, in order to motivate NSPs to employ QoS techniques instead of overprovisioning. Software Defined Networking (SDN) represents a paradigm shift in the way telecommunication and data...... networks are designed and managed. This thesis argues that SDN can greatly simplify QoS provisioning in communication networks, and even improve QoS in various ways. To this end, the impact of SDN on QoS is assessed from both a network performance perspective (e.g. bandwidth, delay), and also from a more...... generic perspective (e.g. service provisioning speed, resources availability). As a result, new mechanisms for providing QoS are proposed, solutions for SDN-specific QoS challenges are designed and tested, and new network management concepts are prototyped, all aiming to improve QoS for network services...

  7. Bio-inspired networking

    CERN Document Server

    Câmara, Daniel

    2015-01-01

    Bio-inspired techniques are based on principles, or models, of biological systems. In general, natural systems present remarkable capabilities of resilience and adaptability. In this book, we explore how bio-inspired methods can solve different problems linked to computer networks. Future networks are expected to be autonomous, scalable and adaptive. During millions of years of evolution, nature has developed a number of different systems that present these and other characteristics required for the next generation networks. Indeed, a series of bio-inspired methods have been successfully used to solve the most diverse problems linked to computer networks. This book presents some of these techniques from a theoretical and practical point of view. Discusses the key concepts of bio-inspired networking to aid you in finding efficient networking solutions Delivers examples of techniques both in theoretical concepts and practical applications Helps you apply nature's dynamic resource and task management to your co...

  8. Macroecology of pollination networks

    DEFF Research Database (Denmark)

    Nielsen, Kristian Trøjelsgaard; Olesen, Jens Mogens

    2013-01-01

    Aim Interacting communities of species are organized into complex networks, and network analysis is reckoned to be a strong tool for describing their architecture. Many species assemblies show strong macroecological patterns, e.g. increasing species richness with decreasing latitude, but whether...... towards the tropics, and that network topology would be affected by current climate. Location Global. Methods Each network was organized as a presence/absence matrix, consisting of P plant species, A pollinator species and their links. From these matrices, network parameters were estimated. Additionally......, data about geography (latitude, elevation), climate at the network site (temperature, precipitation) and sampling effort (observation days) and extent (study-plot size) were gathered. Analyses were done using simultaneous autoregressive modelling (SAR). Results Species richness did not vary strongly...

  9. Social cognitive radio networks

    CERN Document Server

    Chen, Xu

    2015-01-01

    This brief presents research results on social cognitive radio networks, a transformational and innovative networking paradigm that promotes the nexus between social interactions and cognitive radio networks. Along with a review of the research literature, the text examines the key motivation and challenges of social cognitive radio network design. Three socially inspired distributed spectrum sharing mechanisms are introduced: adaptive channel recommendation mechanism, imitation-based social spectrum sharing mechanism, and evolutionarily stable spectrum access mechanism. The brief concludes with a discussion of future research directions which ascertains that exploiting social interactions for distributed spectrum sharing will advance the state-of-the-art of cognitive radio network design, spur a new line of thinking for future wireless networks, and enable novel wireless service and applications.

  10. Professional social networking.

    Science.gov (United States)

    Rowley, Robert D

    2014-12-01

    We review the current state of social communication between healthcare professionals, the role of consumer social networking, and some emerging technologies to address the gaps. In particular, the review covers (1) the current state of loose social networking for continuing medical education (CME) and other broadcast information dissemination; (2) social networking for business promotion; (3) social networking for peer collaboration, including simple communication as well as more robust data-centered collaboration around patient care; and (4) engaging patients on social platforms, including integrating consumer-originated data into the mix of healthcare data. We will see how, as the nature of healthcare delivery moves from the institution-centric way of tradition to a more social and networked ambulatory pattern that we see emerging today, the nature of health IT has also moved from enterprise-centric systems to more socially networked, cloud-based options.

  11. Reconfigureable network node

    Science.gov (United States)

    Vanderveen, Keith B [Tracy, CA; Talbot, Edward B [Livermore, CA; Mayer, Laurence E [Davis, CA

    2008-04-08

    Nodes in a network having a plurality of nodes establish communication links with other nodes using available transmission media, as the ability to establish such links becomes available and desirable. The nodes predict when existing communications links will fail, become overloaded or otherwise degrade network effectiveness and act to establish substitute or additional links before the node's ability to communicate with the other nodes on the network is adversely affected. A node stores network topology information and programmed link establishment rules and criteria. The node evaluates characteristics that predict existing links with other nodes becoming unavailable or degraded. The node then determines whether it can form a communication link with a substitute node, in order to maintain connectivity with the network. When changing its communication links, a node broadcasts that information to the network. Other nodes update their stored topology information and consider the updated topology when establishing new communications links for themselves.

  12. Security for multihop wireless networks

    CERN Document Server

    Khan, Shafiullah

    2014-01-01

    Security for Multihop Wireless Networks provides broad coverage of the security issues facing multihop wireless networks. Presenting the work of a different group of expert contributors in each chapter, it explores security in mobile ad hoc networks, wireless sensor networks, wireless mesh networks, and personal area networks.Detailing technologies and processes that can help you secure your wireless networks, the book covers cryptographic coprocessors, encryption, authentication, key management, attacks and countermeasures, secure routing, secure medium access control, intrusion detection, ep

  13. Clustering signatures classify directed networks

    Science.gov (United States)

    Ahnert, S. E.; Fink, T. M. A.

    2008-09-01

    We use a clustering signature, based on a recently introduced generalization of the clustering coefficient to directed networks, to analyze 16 directed real-world networks of five different types: social networks, genetic transcription networks, word adjacency networks, food webs, and electric circuits. We show that these five classes of networks are cleanly separated in the space of clustering signatures due to the statistical properties of their local neighborhoods, demonstrating the usefulness of clustering signatures as a classifier of directed networks.

  14. Countering Threat Networks

    Science.gov (United States)

    2016-12-21

    throughout Latin America , and their licit and illicit activities span Asia, Europe, and Africa. e. As the power and influence of these organizations has...networks not bound by geography . Intelligence efforts within the shaping phase show threat network linkages in terms of leadership, organization, size...flow of drugs from Central and South America and the Caribbean into the US from threat networks. From the onset, it became readily apparent that

  15. Networks in ATLAS

    Science.gov (United States)

    McKee, Shawn; ATLAS Collaboration

    2017-10-01

    Networks have played a critical role in high-energy physics (HEP), enabling us to access and effectively utilize globally distributed resources to meet the needs of our physicists. Because of their importance in enabling our grid computing infrastructure many physicists have taken leading roles in research and education (R&E) networking, participating in, and even convening, network related meetings and research programs with the broader networking community worldwide. This has led to HEP benefiting from excellent global networking capabilities for little to no direct cost. However, as other science domains ramp-up their need for similar networking it becomes less clear that this situation will continue unchanged. What this means for ATLAS in particular needs to be understood. ATLAS has evolved its computing model since the LHC started based upon its experience with using globally distributed resources. The most significant theme of those changes has been increased reliance upon, and use of, its networks. We will report on a number of networking initiatives in ATLAS including participation in the global perfSONAR network monitoring and measuring efforts of WLCG and OSG, the collaboration with the LHCOPN/LHCONE effort, the integration of network awareness into PanDA, the use of the evolving ATLAS analytics framework to better understand our networks and the changes in our DDM system to allow remote access to data. We will also discuss new efforts underway that are exploring the inclusion and use of software defined networks (SDN) and how ATLAS might benefit from: • Orchestration and optimization of distributed data access and data movement. • Better control of workflows, end to end. • Enabling prioritization of time-critical vs normal tasks • Improvements in the efficiency of resource usage

  16. Personal Network (PN) Applications

    DEFF Research Database (Denmark)

    Prasad, Ramjee; Skouby, K.

    2005-01-01

    The applications of PN will be realised under many scenarios where users can have access to their personal network all the time. This network will enable the user to share critical information, play games, control their home remotely, etc. All this will be achieved with seamless interworking...... and handover between networks and user devices. This paper presents an array of use case scenarios that validates the ubiquitous usage of PN....

  17. Personal network (PN) applications

    DEFF Research Database (Denmark)

    Prasad, R.; Skouby, Knud Erik

    2005-01-01

    The applications of PN will be realised under many scenarios where users can have access to their personal network all the time. This network will enable the user to share critical information, play games, control their home remotely, etc. All this will be achieved with seamless interworking...... and handover between networks and user devices. This paper presents an array of use case scenarios that validates the ubiquitous usage of PN....

  18. Evolution of Social networks

    OpenAIRE

    Hellmann, Tim; Staudigl, Mathias

    2014-01-01

    Modeling the evolution of networks is central to our understanding of modern large communication systems, such as theWorld-Wide-Web, as well as economic and social networks. The research on social and economic networks is truly interdisciplinary and the number of modeling strategies and concepts is enormous. In this survey we present some modeling approaches, covering classical random graph models and game-theoretic models, which may be used to provide a unified framework to model an...

  19. Handbook of networking & connectivity

    CERN Document Server

    McClain, Gary R

    1994-01-01

    Handbook of Networking & Connectivity focuses on connectivity standards in use, including hardware and software options. The book serves as a guide for solving specific problems that arise in designing and maintaining organizational networks.The selection first tackles open systems interconnection, guide to digital communications, and implementing TCP/IP in an SNA environment. Discussions focus on elimination of the SNA backbone, routing SNA over internets, connectionless versus connection-oriented networks, internet concepts, application program interfaces, basic principles of layering, proto

  20. Advanced Polymer Network Structures

    Science.gov (United States)

    2016-02-01

    characteristic time 02 /UmaLJ =τ . Topologically bound monomers interact through the sum of the purely repulsive LJ potential ( arc 6/12= ) or so-called Weeks...3 Content of the simulated polymer double network. Self- attraction coefficient between particles within a network (first or second) is fixed at 1...technique to the study the microscopic topology and dynamics of a wide variety of polymer networks and gels.5–8 The pair interaction between

  1. Network operating system

    Science.gov (United States)

    1985-01-01

    Long-term and short-term objectives for the development of a network operating system for the Space Station are stated. The short-term objective is to develop a prototype network operating system for a 100 megabit/second fiber optic data bus. The long-term objective is to establish guidelines for writing a detailed specification for a Space Station network operating system. Major milestones are noted. Information is given in outline form.

  2. Network Virtualization Protocols

    OpenAIRE

    Fornazarič, Nejc

    2014-01-01

    Server virtualization is a widespread and well known technology that has fundamentally changed the operations in data centers. Virtual servers and data storage can be fast and easily provisioned. On the other hand network requires a lot of administrative changes and configurations that increase time of adoption. The consequences of server virtualization are changed requirements for network resources therefore the next logical step is network virtualization. The different approaches for netwo...

  3. Modeling semiflexible polymer networks

    OpenAIRE

    Broedersz, Chase P.; MacKintosh, Fred C.

    2014-01-01

    Here, we provide an overview of theoretical approaches to semiflexible polymers and their networks. Such semiflexible polymers have large bending rigidities that can compete with the entropic tendency of a chain to crumple up into a random coil. Many studies on semiflexible polymers and their assemblies have been motivated by their importance in biology. Indeed, crosslinked networks of semiflexible polymers form a major structural component of tissue and living cells. Reconstituted networks o...

  4. Stochastic Pooling Networks

    OpenAIRE

    McDonnell, Mark D; Amblard, Pierre-Olivier; Stocks, Nigel G.

    2009-01-01

    We introduce and define the concept of a stochastic pooling network (SPN), as a model for sensor systems where redundancy and two forms of 'noise' -- lossy compression and randomness -- interact in surprising ways. Our approach to analyzing SPNs is information theoretic. We define an SPN as a network with multiple nodes that each produce noisy and compressed measurements of the same information. An SPN must combine all these measurements into a single further compressed network output, in a w...

  5. Information networks and links

    Science.gov (United States)

    Davydov, G. B.

    The basic operating principles of a telecommunications network are described. The technical characteristics of three types of telecommunications network are discussed, including voice-based (telephone) systems; television networks; and data (digital) communications. Among the specific transmission and channeling systems described are: satellite relays; microwae relays; ground based microwave relays; and pulse code modulation; (PCM). The integration of world wide systems for coordinating voice data, and video communications is also discussed.

  6. Airborne Network Camera Standard

    Science.gov (United States)

    2015-06-01

    Optical Systems Group Document 466-15 AIRBORNE NETWORK CAMERA STANDARD DISTRIBUTION A: APPROVED FOR PUBLIC RELEASE...Airborne Network Camera Standard 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER...without the focus of standardization for interoperable command and control, storage, and data streaming has been the airborne network camera systems used

  7. Affinity driven social networks

    Science.gov (United States)

    Ruyú, B.; Kuperman, M. N.

    2007-04-01

    In this work we present a model for evolving networks, where the driven force is related to the social affinity between individuals of a population. In the model, a set of individuals initially arranged on a regular ordered network and thus linked with their closest neighbors are allowed to rearrange their connections according to a dynamics closely related to that of the stable marriage problem. We show that the behavior of some topological properties of the resulting networks follows a non trivial pattern.

  8. Bibliometrics/Citation networks

    OpenAIRE

    Leydesdorff, Loet

    2015-01-01

    In addition to shaping social networks, for example, in terms of co-authorship relations, scientific communications induce and reproduce cognitive structures. Scientific literature is intellectually organized in terms of disciplines and specialties; these structures are reproduced and networked reflexively by making references to the authors, concepts and texts embedded in these literatures. The concept of a cognitive structure was introduced in social network analysis (SNA) in 1987 by David ...

  9. Friendly network robotics; Friendly network robotics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This paper summarizes the research results on the friendly network robotics in fiscal 1996. This research assumes an android robot as an ultimate robot and the future robot system utilizing computer network technology. The robot aiming at human daily work activities in factories or under extreme environments is required to work under usual human work environments. The human robot with similar size, shape and functions to human being is desirable. Such robot having a head with two eyes, two ears and mouth can hold a conversation with human being, can walk with two legs by autonomous adaptive control, and has a behavior intelligence. Remote operation of such robot is also possible through high-speed computer network. As a key technology to use this robot under coexistence with human being, establishment of human coexistent robotics was studied. As network based robotics, use of robots connected with computer networks was also studied. In addition, the R-cube (R{sup 3}) plan (realtime remote control robot technology) was proposed. 82 refs., 86 figs., 12 tabs.

  10. Heterogeneous cellular networks

    CERN Document Server

    Hu, Rose Qingyang

    2013-01-01

    A timely publication providing coverage of radio resource management, mobility management and standardization in heterogeneous cellular networks The topic of heterogeneous cellular networks has gained momentum in industry and the research community, attracting the attention of standardization bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are looking into increasing the capacity and coverage of the cellular networks. This book focuses on recent progresses,  covering the related topics including scenarios of heterogeneous network deployment, interference management i

  11. Networked Instrumentation Element

    Data.gov (United States)

    National Aeronautics and Space Administration — Armstrong researchers have developed a networked instrumentation system that connects modern experimental payloads to existing analog and digital communications...

  12. Power-functional network

    Science.gov (United States)

    Sun, Yong; Kurths, Jürgen; Zhan, Meng

    2017-08-01

    Power grids and their properties have been studied broadly in many aspects. In this paper, we propose a novel concept, power-flow-based power grid, as a typical power-functional network, based on the calculation of power flow distribution from power electrical engineering. We compare it with structural networks based on the shortest path length and effective networks based on the effective electrical distance and study the relationship among these three kinds of networks. We find that they have roughly positive correlations with each other, indicating that in general any close nodes in the topological structure are actually connected in function. However, we do observe some counter-examples that two close nodes in a structural network can have a long distance in a power-functional network, namely, two physically connected nodes can actually be separated in function. In addition, we find that power grids in the structural network tend to be heterogeneous, whereas those in the effective and power-functional networks tend to be homogeneous. These findings are expected to be significant not only for power grids but also for various other complex networks.

  13. Network security risk level

    Directory of Open Access Journals (Sweden)

    Emil BURTESCU

    2006-01-01

    Full Text Available The advantages of the existence of a computers network within any company with pretensions are obvious. But the construction and the existence of a network without meeting some minimum security requirements, although it would be preferable to be optimal, can lead to bad functioning in the performance of the company’s business. The vulnerability of a grouping, such as a network, is given by the weakest point in its competence. The establishing of the risk level of each component of the network, and implicitly of the grouping, is highly necessary

  14. Networks and Interactivity

    DEFF Research Database (Denmark)

    Considine, Mark; Lewis, Jenny

    2012-01-01

    The systemic reform of employment services in OECD countries was driven by New Public Management (NPM) and then post-NPM reforms, when first-phase changes such as privatization were amended with `joined up' processes to help manage fragmentation. This article examines the networking strategies...... of `street-level' employment services staff for the impacts of this. Contrary to expectations, networking has generally declined over the last decade. There are signs of path dependence in networking patterns within each country, but also a convergence of patterns for the UK and Australia......, but not The Netherlands. Networking appears to be mediated by policy and regulatory imperatives....

  15. Seven Deadliest Network Attacks

    CERN Document Server

    Prowell, Stacy; Borkin, Mike

    2010-01-01

    Do you need to keep up with the latest hacks, attacks, and exploits effecting networks? Then you need Seven Deadliest Network Attacks. This book pinpoints the most dangerous hacks and exploits specific to networks, laying out the anatomy of these attacks including how to make your system more secure. You will discover the best ways to defend against these vicious hacks with step-by-step instruction and learn techniques to make your computer and network impenetrable. Attacks detailed in this book include: Denial of Service War Dialing Penetration "Testing" Protocol Tunneling Spanning Tree At

  16. Drawing rooted phylogenetic networks.

    Science.gov (United States)

    Huson, Daniel H

    2009-01-01

    The evolutionary history of a collection of species is usually represented by a phylogenetic tree. Sometimes, phylogenetic networks are used as a means of representing reticulate evolution or of showing uncertainty and incompatibilities in evolutionary datasets. This is often done using unrooted phylogenetic networks such as split networks, due in part, to the availability of software (SplitsTree) for their computation and visualization. In this paper we discuss the problem of drawing rooted phylogenetic networks as cladograms or phylograms in a number of different views that are commonly used for rooted trees. Implementations of the algorithms are available in new releases of the Dendroscope and SplitsTree programs.

  17. Mixing navigation on networks

    Science.gov (United States)

    Zhou, Tao

    2008-05-01

    In this article, we propose a mixing navigation mechanism, which interpolates between random-walk and shortest-path protocol. The navigation efficiency can be remarkably enhanced via a few routers. Some advanced strategies are also designed: For non-geographical scale-free networks, the targeted strategy with a tiny fraction of routers can guarantee an efficient navigation with low and stable delivery time almost independent of network size. For geographical localized networks, the clustering strategy can simultaneously increase efficiency and reduce the communication cost. The present mixing navigation mechanism is of significance especially for information organization of wireless sensor networks and distributed autonomous robotic systems.

  18. Mobile ad hoc networking

    CERN Document Server

    John Wiley & Sons

    2004-01-01

    "Assimilating the most up-to-date information on research and development activities in this rapidly growing area, Mobile Ad Hoc Networking covers physical, data link, network, and transport layers, as well as application, security, simulation, and power management issues in sensor, local area, personal, and mobile ad hoc networks. Each of the book's sixteen chapters has been written by a top expert and discusses in-depth the most important topics in the field. Mobile Ad Hoc Networking is an excellent reference and guide for professionals seeking an in-depth examination of topics that also provides a comprehensive overview of the current state-of-the-art."--Jacket.

  19. Physical Layer Network Coding

    DEFF Research Database (Denmark)

    Fukui, Hironori; Yomo, Hironori; Popovski, Petar

    2013-01-01

    Physical layer network coding (PLNC) has the potential to improve throughput of multi-hop networks. However, most of the works are focused on the simple, three-node model with two-way relaying, not taking into account the fact that there can be other neighboring nodes that can cause/receive inter......Physical layer network coding (PLNC) has the potential to improve throughput of multi-hop networks. However, most of the works are focused on the simple, three-node model with two-way relaying, not taking into account the fact that there can be other neighboring nodes that can cause...

  20. Optical network democratization.

    Science.gov (United States)

    Nejabati, Reza; Peng, Shuping; Simeonidou, Dimitra

    2016-03-06

    The current Internet infrastructure is not able to support independent evolution and innovation at physical and network layer functionalities, protocols and services, while at same time supporting the increasing bandwidth demands of evolving and heterogeneous applications. This paper addresses this problem by proposing a completely democratized optical network infrastructure. It introduces the novel concepts of the optical white box and bare metal optical switch as key technology enablers for democratizing optical networks. These are programmable optical switches whose hardware is loosely connected internally and is completely separated from their control software. To alleviate their complexity, a multi-dimensional abstraction mechanism using software-defined network technology is proposed. It creates a universal model of the proposed switches without exposing their technological details. It also enables a conventional network programmer to develop network applications for control of the optical network without specific technical knowledge of the physical layer. Furthermore, a novel optical network virtualization mechanism is proposed, enabling the composition and operation of multiple coexisting and application-specific virtual optical networks sharing the same physical infrastructure. Finally, the optical white box and the abstraction mechanism are experimentally evaluated, while the virtualization mechanism is evaluated with simulation. © 2016 The Author(s).

  1. Global Operations Networks

    DEFF Research Database (Denmark)

    In the current context of global economic liberalisation and technological advancements, industrial companies are less likely to generate value in the traditional vertically integrated chain. Instead, they are doing so by means of elaborate cross-border and cross-organisational networks. As a rule...... and processes in global operations networks, and • Trajectories and reconfiguration of global operations networks. The themes are intended to incorporate elements which in combination provide a comprehensive multidisciplinary view on operations networks. Behind these themes lay clusters of questions and topics...

  2. Transportation network reduction

    Directory of Open Access Journals (Sweden)

    Stanislav PALÚCH

    2015-06-01

    Full Text Available Network reduction problem is formulated as follows: We are given a transportation network T, a set of important origin – destination relations R and a number q greater than 1. The goal is to find a subnetwork S of the given network T such that all shortest paths between all origin – destination pairs from R using only subnetwork S are not longer than q-multiple of the corresponding distance in original network T. A mathematical model and an exact algorithm of just mentioned task is presented.

  3. Network Monitoring with Nagios

    CERN Document Server

    Dondich, Taylor

    2006-01-01

    Network monitoring can be a complex task to implement and maintain in your IT infrastructure. Nagios, an open-source host, service and network monitoring program can help you streamline your network monitoring tasks and reduce the cost of operation.With this shortcut guide, we'll go over how Nagios fits in the overall network monitoring puzzle. We'll also cover installation and basic usage. Finally, we'll show you how to extend Nagios with other tools to extend functionality.

  4. Sharing network resources

    CERN Document Server

    Parekh, Abhay

    2014-01-01

    Resource Allocation lies at the heart of network control. In the early days of the Internet the scarcest resource was bandwidth, but as the network has evolved to become an essential utility in the lives of billions, the nature of the resource allocation problem has changed. This book attempts to describe the facets of resource allocation that are most relevant to modern networks. It is targeted at graduate students and researchers who have an introductory background in networking and who desire to internalize core concepts before designing new protocols and applications. We start from the fun

  5. Sustainable wireless networks

    CERN Document Server

    Zheng, Zhongming; Xuemin

    2013-01-01

    This brief focuses on network planning and resource allocation by jointly considering cost and energy sustainability in wireless networks with sustainable energy. The characteristics of green energy and investigating existing energy-efficient green approaches for wireless networks with sustainable energy is covered in the first part of this brief. The book then addresses the random availability and capacity of the energy supply. The authors explore how to maximize the energy sustainability of the network and minimize the failure probability that the mesh access points (APs) could deplete their

  6. Mobile Virtual Private Networking

    Science.gov (United States)

    Pulkkis, Göran; Grahn, Kaj; Mårtens, Mathias; Mattsson, Jonny

    Mobile Virtual Private Networking (VPN) solutions based on the Internet Security Protocol (IPSec), Transport Layer Security/Secure Socket Layer (SSL/TLS), Secure Shell (SSH), 3G/GPRS cellular networks, Mobile IP, and the presently experimental Host Identity Protocol (HIP) are described, compared and evaluated. Mobile VPN solutions based on HIP are recommended for future networking because of superior processing efficiency and network capacity demand features. Mobile VPN implementation issues associated with the IP protocol versions IPv4 and IPv6 are also evaluated. Mobile VPN implementation experiences are presented and discussed.

  7. Exploring complex networks.

    Science.gov (United States)

    Strogatz, S H

    2001-03-08

    The study of networks pervades all of science, from neurobiology to statistical physics. The most basic issues are structural: how does one characterize the wiring diagram of a food web or the Internet or the metabolic network of the bacterium Escherichia coli? Are there any unifying principles underlying their topology? From the perspective of nonlinear dynamics, we would also like to understand how an enormous network of interacting dynamical systems-be they neurons, power stations or lasers-will behave collectively, given their individual dynamics and coupling architecture. Researchers are only now beginning to unravel the structure and dynamics of complex networks.

  8. International Rehabilitation Network

    National Research Council Canada - National Science Library

    Smith, William

    2001-01-01

    The International Rehabilitation Network's goal is to improve the quality of services for land mine survivors and other amputee's through the dissemination of educational programs to rehabilitation professionals...

  9. Mobile networks architecture

    CERN Document Server

    Perez, Andre

    2013-01-01

    This book explains the evolutions of architecture for mobiles and summarizes the different technologies:- 2G: the GSM (Global System for Mobile) network, the GPRS (General Packet Radio Service) network and the EDGE (Enhanced Data for Global Evolution) evolution;- 3G: the UMTS (Universal Mobile Telecommunications System) network and the HSPA (High Speed Packet Access) evolutions:- HSDPA (High Speed Downlink Packet Access),- HSUPA (High Speed Uplink Packet Access),- HSPA+;- 4G: the EPS (Evolved Packet System) network.The telephone service and data transmission are the

  10. Effective professional networking.

    Science.gov (United States)

    Goolsby, Mary Jo; Knestrick, Joyce M

    2017-08-01

    The reasons for nurse practitioners to develop a professional network are boundless and are likely to change over time. Networking opens doors and creates relationships that support new opportunities, personal development, collaborative research, policy activism, evidence-based practice, and more. Successful professional networking involves shared, mutually beneficial interactions between individuals and/or individuals and groups, regardless of whether it occurs face to face or electronically. This article combines nuggets from the literature with guidance based on the authors' combined experience in networking activities at the local, national, and international levels. ©2017 American Association of Nurse Practitioners.

  11. Modeling network technology deployment rates with different network models

    OpenAIRE

    Chung, Yoo

    2011-01-01

    To understand the factors that encourage the deployment of a new networking technology, we must be able to model how such technology gets deployed. We investigate how network structure influences deployment with a simple deployment model and different network models through computer simulations. The results indicate that a realistic model of networking technology deployment should take network structure into account.

  12. Forman curvature for directed networks

    CERN Document Server

    Sreejith, R P; Saucan, Emil; Samal, Areejit

    2016-01-01

    A goal in network science is the geometrical characterization of complex networks. In this direction, we have recently introduced the Forman's discretization of Ricci curvature to the realm of undirected networks. Investigation of Forman curvature in diverse model and real-world undirected networks revealed that this measure captures several aspects of the organization of complex undirected networks. However, many important real-world networks are inherently directed in nature, and the Forman curvature for undirected networks is unsuitable for analysis of such directed networks. Hence, we here extend the Forman curvature for undirected networks to the case of directed networks. The simple mathematical formula for the Forman curvature in directed networks elegantly incorporates node weights, edge weights and edge direction. By applying the Forman curvature for directed networks to a variety of model and real-world directed networks, we show that the measure can be used to characterize the structure of complex ...

  13. Network Coding for Wireless Cooperative Networks

    DEFF Research Database (Denmark)

    Khamfroush, Hana; Roetter, Daniel Enrique Lucani; Barros, João

    2014-01-01

    We consider the problem of finding an optimal packet transmission policy that minimizes the total cost of transmitting M data packets from a source S to two receivers R1,R2 over half-duplex, erasure channels. The source can either broadcast random linear network coding (RLNC) packets to the recei......We consider the problem of finding an optimal packet transmission policy that minimizes the total cost of transmitting M data packets from a source S to two receivers R1,R2 over half-duplex, erasure channels. The source can either broadcast random linear network coding (RLNC) packets...

  14. Graph measures and network robustness

    NARCIS (Netherlands)

    Ellens, W.; Kooij, R.E.

    2013-01-01

    Network robustness research aims at finding a measure to quantify network robustness. Once such a measure has been established, we will be able to compare networks, to improve existing networks and to design new networks that are able to continue to perform well when it is subject to failures or

  15. Entrepreneurial orientation and network board diversity in network organizations

    National Research Council Canada - National Science Library

    Wincent, Joakim; Thorgren, Sara; Anokhin, Sergey

    2014-01-01

    This study extends the concept of entrepreneurial orientation (EO) to the network level to investigate how diversity among officers serving on network organization boards affects network-level entrepreneurial orientation (NEO...

  16. Network Routing Using the Network Tasking Order, a Chron Approach

    Science.gov (United States)

    2015-03-26

    iv BATMAN Better Approach to Mobile Ad-hoc Networks...routing in wireless mesh networks. MicroTik has created MME based on the Better Approach to Mobile Ad-hoc Network ( BATMAN ) routing protocol. MME

  17. Security-Enhanced Autonomous Network Management for Space Networking Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's Space Communications and Navigation (SCaN) program is integrating its three current agency networks: Space Network (SN), Deep Space Network (DSN), and Near...

  18. KNOWLEDGE TRANSFER THROUGH NETWORKS

    Directory of Open Access Journals (Sweden)

    GYÖRGY ATTILA

    2012-06-01

    Full Text Available Knowledge is a vital intangible asset for any organization and cannot be valued exactly due its special form of materialization. Although we have this drawback, a scientifically established value should be used in order to measure the performance of knowledge holders. A correct valuation helps to know the worth of assets offered in exploitation. Exploitation of this resource could be done in several different ways, but integration in knowledge networks seems to generate best efficiency ratio. Networks offer the possibility to change information, to obtain new information, to build further ideas arose from network partners or to develop together new ideas. Thus, networks assure conditions to optimize the members’ knowledge portfolios. Optimization of knowledge usage creates benefits for network members. These benefits could be profits (if members are private companies or social welfare (if members are looking after collective purposes. Taxonomy of knowledge networks is diverse, permitting an adaptation to the needs of members. Networks permit a large scale of heterogeneity. Since an important part of new knowledge creating costs is covered from public budgetary resources, a special development is recorded at those networks which are exclusively or partly organized in the public sector or benefit by participation from the public sector.

  19. Integrating networks with Mathematica

    NARCIS (Netherlands)

    Strijkers, R.J.; Meijer, R.J.

    2008-01-01

    We have developed a concept that considers network behavior as a collection of software objects, which can be used or modified in computer programs. The interfaces of these software objects are exposed as web services and enable applications to analyze and manipulate networks, e.g. to find

  20. Home Network Security

    NARCIS (Netherlands)

    Scholten, Johan; van Dijk, H.W.

    2008-01-01

    Service discovery and secure and safe service usage are essential elements in the deployment of home and personal networks. Because no system administrator is present, setup and daily operation of such a network has to be automated as much as possible with a high degree of user friendliness. To

  1. Triangulation positioning system network

    Directory of Open Access Journals (Sweden)

    Sfendourakis Marios

    2017-01-01

    Full Text Available This paper presents ongoing work on localization and positioning through triangulation procedure for a Fixed Sensors Network - FSN.The FSN has to work as a system.As the triangulation problem becomes high complicated in a case with large numbers of sensors and transmitters, an adequate grid topology is needed in order to tackle the detection complexity.For that reason a Network grid topology is presented and areas that are problematic and need further analysis are analyzed.The Network System in order to deal with problems of saturation and False Triangulations - FTRNs will have to find adequate methods in every sub-area of the Area Of Interest - AOI.Also, concepts like Sensor blindness and overall Network blindness, are presented. All these concepts affect the Network detection rate and its performance and ought to be considered in a way that the network overall performance won’t be degraded.Network performance should be monitored contentiously, with right algorithms and methods.It is also shown that as the number of TRNs and FTRNs is increased Detection Complexity - DC is increased.It is hoped that with further research all the characteristics of a triangulation system network for positioning will be gained and the system will be able to perform autonomously with a high detection rate.

  2. Wireless networked music performance

    CERN Document Server

    Gabrielli, Leonardo

    2016-01-01

    This book presents a comprehensive overview of the state of the art in Networked Music Performance (NMP) and a historical survey of computer music networking. It introduces current technical trends in NMP and technical issues yet to be addressed. It also lists wireless communication protocols and compares these to the requirements of NMP. Practical use cases and advancements are also discussed.

  3. Network Collaboration with UNIX.

    Science.gov (United States)

    Horn, Wm. Dennis

    1993-01-01

    Discusses networking as a collaboration tool in the teaching of technical writing. Argues that some degree of collaboration is innate to all writing, that word processing already facilitates that collaboration, and that networking is the next enhancement to the collaborative process. (RS)

  4. Innovation in Virtual Networks

    DEFF Research Database (Denmark)

    Hu, Yimei; Sørensen, Olav Jull

    2011-01-01

    The purpose of this article is to explore and highlight the particular innovation characteristics and modes of the chinese game industry from a networking perspective......The purpose of this article is to explore and highlight the particular innovation characteristics and modes of the chinese game industry from a networking perspective...

  5. Untangle network security

    CERN Document Server

    El-Bawab, Abd El-Monem A

    2014-01-01

    If you are a security engineer or a system administrator and want to secure your server infrastructure with the feature-rich Untangle, this book is for you. For individuals who want to start their career in the network security field, this book would serve as a perfect companion to learn the basics of network security and how to implement it using Untangle NGFW.

  6. Weaponizing Wireless Networks

    DEFF Research Database (Denmark)

    Giannetsos, Athanasios; Tassos, Dimitriou; Prasad, Neeli R.

    2010-01-01

    of a sensor network. Results show that our tool can be flexibly applied to different sensor network operating systems and protocol stacks giving an adversary privileges to which she is not entitled to. We hope that our tool will be used proactively, to study the weaknesses of new security protocols, and......, hopefully, to enhance the level of security provided by these solutions even further....

  7. Information Theory of Networks

    Directory of Open Access Journals (Sweden)

    Matthias Dehmer

    2011-11-01

    Full Text Available The paper puts the emphasis on surveying information-theoretic network measures for analyzing the structure of networks. In order to apply the quantities interdisciplinarily, we also discuss some of their properties such as their structural interpretation and uniqueness.

  8. Understanding telecommunications networks

    CERN Document Server

    Valdar, Andy

    2017-01-01

    A telecommunications network is an electronic system of links, nodes and the controls that govern their operations to allow voice and data transfer among users and devices. This fully revised, updated and expanded second edition covers all aspects of today's networks, including how they are planned, formed and operated.

  9. Clustering of correlated networks

    OpenAIRE

    Dorogovtsev, S. N.

    2003-01-01

    We obtain the clustering coefficient, the degree-dependent local clustering, and the mean clustering of networks with arbitrary correlations between the degrees of the nearest-neighbor vertices. The resulting formulas allow one to determine the nature of the clustering of a network.

  10. Recurrent Spatial Transformer Networks

    DEFF Research Database (Denmark)

    Sønderby, Søren Kaae; Sønderby, Casper Kaae; Maaløe, Lars

    2015-01-01

    We integrate the recently proposed spatial transformer network (SPN) [Jaderberg et. al 2015] into a recurrent neural network (RNN) to form an RNN-SPN model. We use the RNN-SPN to classify digits in cluttered MNIST sequences. The proposed model achieves a single digit error of 1.5% compared to 2...

  11. Network cities and externalities

    Directory of Open Access Journals (Sweden)

    Rafael Boix Domènech

    2004-01-01

    Full Text Available The concept of «agglomeration economies» explains the existence of advantages derived from the concentration of population and activity. However, it does not explain the existence of spatially dynamic external economies. Network economies generated in networks of cities correspond to this last type, since they are generated from the interaction between urban units, linked by a network relationship. The objective of this research is to advance in the study of the relationship between the networks of cities and the generation of external economies. The research is divided in four parts: first we expose the link between networks of cities and external economies. The second part outlines a model for the combined measuring of the concentration and network economies. The third part explains the results of applying the model to a case of study: the network of cities of Catalonia. The results suggest that there is a causal relationship between the organization of the urban units forming networks of cities and the generation of external economies that affect growth and economic development. Finally, conclusions and policy implications are drawn up.

  12. Community Wireless Networks

    Science.gov (United States)

    Feld, Harold

    2005-01-01

    With increasing frequency, communities are seeing the arrival of a new class of noncommercial broadband providers: community wireless networks (CWNs). Utilizing the same wireless technologies that many colleges and universities have used to create wireless networks on campus, CWNs are creating broadband access for free or at costs well below…

  13. Synchronization of networks

    Indian Academy of Sciences (India)

    with time. Such a time-varying topology can occur in social networks, computer networks, WWW, biological systems, spread of epidemics etc. Here, we investigate ... this periodic rotation is to take projections of different expansions and contrac- tions along different directions. This has the effect of reducing the spread of the.

  14. Teacher Networks Companion Piece

    Science.gov (United States)

    Hopkins, Ami Patel; Rulli, Carolyn; Schiff, Daniel; Fradera, Marina

    2015-01-01

    Network building vitally impacts career development, but in few professions does it impact daily practice more than in teaching. Teacher networks, known as professional learning communities, communities of practice, peer learning circles, virtual professional communities, as well as other names, play a unique and powerful role in education. In…

  15. Wireless Sensors Network (Sensornet)

    Science.gov (United States)

    Perotti, J.

    2003-01-01

    The Wireless Sensor Network System presented in this paper provides a flexible reconfigurable architecture that could be used in a broad range of applications. It also provides a sensor network with increased reliability; decreased maintainability costs, and assured data availability by autonomously and automatically reconfiguring to overcome communication interferences.

  16. Next Generation Social Networks

    DEFF Research Database (Denmark)

    Sørensen, Lene Tolstrup; Skouby, Knud Erik

    2008-01-01

    When it comes to discussing the future of electronic communication, social networking is the buzzword. The Internet has become a platform where new social networks emerge and the Internet it itself support the more traditional computer supported communication. The way users build and verifies...

  17. Robustness Envelopes of Networks

    NARCIS (Netherlands)

    Trajanovski, S.; Martín-Hernández, J.; Winterbach, W.; Van Mieghem, P.

    2013-01-01

    We study the robustness of networks under node removal, considering random node failure, as well as targeted node attacks based on network centrality measures. Whilst both of these have been studied in the literature, existing approaches tend to study random failure in terms of average-case

  18. Convergence of Networks

    DEFF Research Database (Denmark)

    Prasad, Ramjee; Ruggieri, Marina

    2008-01-01

    The paper focuses on the revolutionary changes that could characterise the future of networks. Those changes involve many aspects in the conceivement and exploitation of networks: architecture, services, technologies and modeling. The convergence of wired and wireless technologies along with the ...

  19. International tourism network

    Science.gov (United States)

    Miguéns, Joana I. L.; Mendes, José F. F.; Costa, Carlos M. M.

    2007-06-01

    The interest in tourism has always been strong, for its important role in economic flows among nations. On this study we analyze the arrivals of international tourism (edges) over 206 countries and territories (nodes) around the world, on the year 2004. International tourist arrivals reached a record of 763 million in 2004. We characterize analytically the topological and weighted properties of the resulting network. International tourist arrivals are analyzed over in strength and out strength flows, resulting on a highly directed network, with a very heterogeneity of weights and strengths. The inclusion of edge weights and directions on the analysis of network architecture allows a more realistic insight on the structure of the networks. Centrality, assortativity and disparity are measured for the topological and weighted structure. Assortativity measures the tendency of having a high weight edges connecting two nodes with similar degrees. ITN is disassortative, opposite to social network. Disparity quantifies the how similar are the flows on a node neighborhood, measuring the heterogeneity of weights for in flows and out flows of tourism. These results provide an application of the recent methods of weighted and directed networks, showing that weights are relevant and that in general the modeling of complex networks must go beyond topology. The network structure may influence how tourism hubs, distribution of flows, and centralization can be explored on countries strategic positioning and policy making.

  20. Personalized Home-Networks

    DEFF Research Database (Denmark)

    Soler, José; Gandy, Michael

    2007-01-01

    The paper provides details of a home-networking architecture based on an enhanced residential gateway. Initially the need for mechanisms allowing user-dependent network behavior is described and afterwards details of an initial implementation are provided in terms of architectural description...

  1. Online Social Network Interactions:

    Directory of Open Access Journals (Sweden)

    Hui-Jung Chang

    2018-01-01

    Full Text Available A cross-cultural comparison of social networking structure on McDonald’s Facebook fan sites between Taiwan and the USA was conducted utilizing the individualism/collectivism dimension proposed by Hofstede. Four network indicators are used to describe the network structure of McDonald’s Facebook fan sites: size, density, clique and centralization. Individuals who post on both Facebook sites for the year of 2012 were considered as network participants for the purpose of the study. Due to the huge amount of data, only one thread of postings was sampled from each month of the year of 2012. The final data consists of 1002 postings written by 896 individuals and 5962 postings written by 5532 individuals from Taiwan and the USA respectively. The results indicated that the USA McDonald’s Facebook fan network has more fans, while Taiwan’s McDonald’s Facebook fan network is more densely connected. Cliques did form among the overall multiplex and within the individual uniplex networks in two countries, yet no significant differences were found between them. All the fan networks in both countries are relatively centralized, mostly on the site operators.

  2. Networking: OFFLU example

    Science.gov (United States)

    World Organization for Animal Health (OIE) and Food and Agriculture Organization (FAO) for the United Nations Influenza Network (OFFLU) is the joint OIE-FAO global network of expertise on animal influenzas: equine, swine, poultry and wild birds. OFFLU aims to reduce negative impacts of animal influ...

  3. Networking wireless sensors

    National Research Council Canada - National Science Library

    Krishnamachari, Bhaskar

    2005-01-01

    ... by networking techniques across multiple layers. The topics covered include network deployment, localization, time synchronization, wireless radio characteristics, medium-access, topology control, routing, data-centric techniques, and transport protocols. Ideal for researchers and designers seeking to create new algorithms and protocols and enginee...

  4. Networking in Academia.

    Science.gov (United States)

    Fattig, W. Donald

    1984-01-01

    Discusses the use of microcomputers as communication devices and presents features of several national bibliographic networks, together with examples of searches for information of interest to academics. The status of electronic publishing is discussed and differences between national and local area networks are described. (Author)

  5. Deep Spiking Networks

    NARCIS (Netherlands)

    O'Connor, P.; Welling, M.

    2016-01-01

    We introduce an algorithm to do backpropagation on a spiking network. Our network is "spiking" in the sense that our neurons accumulate their activation into a potential over time, and only send out a signal (a "spike") when this potential crosses a threshold and the neuron is reset. Neurons only

  6. Brain Network Modelling

    DEFF Research Database (Denmark)

    Andersen, Kasper Winther

    Three main topics are presented in this thesis. The first and largest topic concerns network modelling of functional Magnetic Resonance Imaging (fMRI) and Diffusion Weighted Imaging (DWI). In particular nonparametric Bayesian methods are used to model brain networks derived from resting state f...... for their ability to reproduce node clustering and predict unseen data. Comparing the models on whole brain networks, BCD and IRM showed better reproducibility and predictability than IDM, suggesting that resting state networks exhibit community structure. This also points to the importance of using models, which...... allow for complex interactions between all pairs of clusters. In addition, it is demonstrated how the IRM can be used for segmenting brain structures into functionally coherent clusters. A new nonparametric Bayesian network model is presented. The model builds upon the IRM and can be used to infer...

  7. Hidden neural networks

    DEFF Research Database (Denmark)

    Krogh, Anders Stærmose; Riis, Søren Kamaric

    1999-01-01

    A general framework for hybrids of hidden Markov models (HMMs) and neural networks (NNs) called hidden neural networks (HNNs) is described. The article begins by reviewing standard HMMs and estimation by conditional maximum likelihood, which is used by the HNN. In the HNN, the usual HMM probability...... parameters are replaced by the outputs of state-specific neural networks. As opposed to many other hybrids, the HNN is normalized globally and therefore has a valid probabilistic interpretation. All parameters in the HNN are estimated simultaneously according to the discriminative conditional maximum...... likelihood criterion. The HNN can be viewed as an undirected probabilistic independence network (a graphical model), where the neural networks provide a compact representation of the clique functions. An evaluation of the HNN on the task of recognizing broad phoneme classes in the TIMIT database shows clear...

  8. Complex Networks IX

    CERN Document Server

    Coronges, Kate; Gonçalves, Bruno; Sinatra, Roberta; Vespignani, Alessandro; Proceedings of the 9th Conference on Complex Networks; CompleNet 2018

    2018-01-01

    This book aims to bring together researchers and practitioners working across domains and research disciplines to measure, model, and visualize complex networks. It collects the works presented at the 9th International Conference on Complex Networks (CompleNet) 2018 in Boston, MA in March, 2018. With roots in physical, information and social science, the study of complex networks provides a formal set of mathematical methods, computational tools and theories to describe prescribe and predict dynamics and behaviors of complex systems. Despite their diversity, whether the systems are made up of physical, technological, informational, or social networks, they share many common organizing principles and thus can be studied with similar approaches. This book provides a view of the state-of-the-art in this dynamic field and covers topics such as group decision-making, brain and cellular connectivity, network controllability and resiliency, online activism, recommendation systems, and cyber security.

  9. Optical Access Networks

    Science.gov (United States)

    Zheng, Jun; Ansari, Nirwan

    2005-01-01

    Call for Papers: Optical Access Networks Guest Editors Jun Zheng, University of Ottawa Nirwan Ansari, New Jersey Institute of Technology Submission Deadline: 1 June 2005 h2>Backgroundh2> With the wide deployment of fiber-optic technology over the past two decades, we have witnessed a tremendous growth of bandwidth capacity in the backbone networks of today's telecommunications infrastructure. However, access networks, which cover the "last-mile" areas and serve numerous residential and small business users, have not been scaled up commensurately. The local subscriber lines for telephone and cable television are still using twisted pairs and coaxial cables. Most residential connections to the Internet are still through dial-up modems operating at a low speed on twisted pairs. As the demand for access bandwidth increases with emerging high-bandwidth applications, such as distance learning, high-definition television (HDTV), and video on demand (VoD), the last-mile access networks have become a bandwidth bottleneck in today's telecommunications infrastructure. To ease this bottleneck, it is imperative to provide sufficient bandwidth capacity in the access networks to open the bottleneck and thus present more opportunities for the provisioning of multiservices. Optical access solutions promise huge bandwidth to service providers and low-cost high-bandwidth services to end users and are therefore widely considered the technology of choice for next-generation access networks. To realize the vision of optical access networks, however, many key issues still need to be addressed, such as network architectures, signaling protocols, and implementation standards. The major challenges lie in the fact that an optical solution must be not only robust, scalable, and flexible, but also implemented at a low cost comparable to that of existing access solutions in order to increase the economic viability of many potential high-bandwidth applications. In recent years, optical access

  10. Minimum cost connection networks

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    2015-01-01

    In the present paper we consider the allocation of costs in connection networks. Agents have connection demands in form of pairs of locations they want to have connected. Connections between locations are costly to build. The problem is to allocate costs of networks satisfying all connection...... demands. We use a few axioms to characterize allocation rules that truthfully implement cost minimizing networks satisfying all connection demands in a game where: (1) a central planner announces an allocation rule and a cost estimation rule; (2) every agent reports her own connection demand as well...... as all connection costs; (3) the central planner selects a cost minimizing network satisfying reported connection demands based on the estimated costs; and, (4) the planner allocates the true costs of the selected network. It turns out that an allocation rule satisfies the axioms if and only if relative...

  11. High-Performance Networking

    CERN Document Server

    CERN. Geneva

    2003-01-01

    The series will start with an historical introduction about what people saw as high performance message communication in their time and how that developed to the now to day known "standard computer network communication". It will be followed by a far more technical part that uses the High Performance Computer Network standards of the 90's, with 1 Gbit/sec systems as introduction for an in depth explanation of the three new 10 Gbit/s network and interconnect technology standards that exist already or emerge. If necessary for a good understanding some sidesteps will be included to explain important protocols as well as some necessary details of concerned Wide Area Network (WAN) standards details including some basics of wavelength multiplexing (DWDM). Some remarks will be made concerning the rapid expanding applications of networked storage.

  12. Networks in cognitive science.

    Science.gov (United States)

    Baronchelli, Andrea; Ferrer-i-Cancho, Ramon; Pastor-Satorras, Romualdo; Chater, Nick; Christiansen, Morten H

    2013-07-01

    Networks of interconnected nodes have long played a key role in Cognitive Science, from artificial neural networks to spreading activation models of semantic memory. Recently, however, a new Network Science has been developed, providing insights into the emergence of global, system-scale properties in contexts as diverse as the Internet, metabolic reactions, and collaborations among scientists. Today, the inclusion of network theory into Cognitive Sciences, and the expansion of complex-systems science, promises to significantly change the way in which the organization and dynamics of cognitive and behavioral processes are understood. In this paper, we review recent contributions of network theory at different levels and domains within the Cognitive Sciences. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Modular Brain Networks.

    Science.gov (United States)

    Sporns, Olaf; Betzel, Richard F

    2016-01-01

    The development of new technologies for mapping structural and functional brain connectivity has led to the creation of comprehensive network maps of neuronal circuits and systems. The architecture of these brain networks can be examined and analyzed with a large variety of graph theory tools. Methods for detecting modules, or network communities, are of particular interest because they uncover major building blocks or subnetworks that are particularly densely connected, often corresponding to specialized functional components. A large number of methods for community detection have become available and are now widely applied in network neuroscience. This article first surveys a number of these methods, with an emphasis on their advantages and shortcomings; then it summarizes major findings on the existence of modules in both structural and functional brain networks and briefly considers their potential functional roles in brain evolution, wiring minimization, and the emergence of functional specialization and complex dynamics.

  14. Reworking the language network.

    Science.gov (United States)

    Fedorenko, Evelina; Thompson-Schill, Sharon L

    2014-03-01

    Prior investigations of functional specialization have focused on the response profiles of particular brain regions. Given the growing emphasis on regional covariation, we propose to reframe these questions in terms of brain 'networks' (collections of regions jointly engaged by some mental process). Despite the challenges that investigations of the language network face, a network approach may prove useful in understanding the cognitive architecture of language. We propose that a language network plausibly includes a functionally specialized 'core' (brain regions that coactivate with each other during language processing) and a domain-general 'periphery' (a set of brain regions that may coactivate with the language core regions at some times but with other specialized systems at other times, depending on task demands). Framing the debate around network properties such as this may prove to be a more fruitful way to advance our understanding of the neurobiology of language. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Decentralized Online Social Networks

    Science.gov (United States)

    Datta, Anwitaman; Buchegger, Sonja; Vu, Le-Hung; Strufe, Thorsten; Rzadca, Krzysztof

    Current Online social networks (OSN) are web services run on logically centralized infrastructure. Large OSN sites use content distribution networks and thus distribute some of the load by caching for performance reasons, nevertheless there is a central repository for user and application data. This centralized nature of OSNs has several drawbacks including scalability, privacy, dependence on a provider, need for being online for every transaction, and a lack of locality. There have thus been several efforts toward decentralizing OSNs while retaining the functionalities offered by centralized OSNs. A decentralized online social network (DOSN) is a distributed system for social networking with no or limited dependency on any dedicated central infrastructure. In this chapter we explore the various motivations of a decentralized approach to online social networking, discuss several concrete proposals and types of DOSN as well as challenges and opportunities associated with decentralization.

  16. Online social support networks.

    Science.gov (United States)

    Mehta, Neil; Atreja, Ashish

    2015-04-01

    Peer support groups have a long history and have been shown to improve health outcomes. With the increasing familiarity with online social networks like Facebook and ubiquitous access to the Internet, online social support networks are becoming popular. While studies have shown the benefit of these networks in providing emotional support or meeting informational needs, robust data on improving outcomes such as a decrease in health services utilization or reduction in adverse outcomes is lacking. These networks also pose unique challenges in the areas of patient privacy, funding models, quality of content, and research agendas. Addressing these concerns while creating patient-centred, patient-powered online support networks will help leverage these platforms to complement traditional healthcare delivery models in the current environment of value-based care.

  17. Visualization of Social Networks

    Science.gov (United States)

    Chen, Ing-Xiang; Yang, Cheng-Zen

    With the ubiquitous characteristic of the Internet, today many online social environments are provided to connect people. Various social relationships are thus created, connected, and migrated from our real lives to the Internet environment from different social groups. Many social communities and relationships are also quickly constructed and connected via instant personal messengers, blogs, Twitter, Facebook, and a great variety of online social services. Since social network visualizations can structure the complex relationships between different groups of individuals or organizations, they are helpful to analyze the social activities and relationships of actors, particularly over a large number of nodes. Therefore, many studies and visualization tools have been investigated to present social networks with graph representations. In this chapter, we will first review the background of social network analysis and visualization methods, and then introduce various novel visualization applications for social networks. Finally, the challenges and the future development of visualizing online social networks are discussed.

  18. Managing Cisco network security

    CERN Document Server

    Knipp, Eric

    2002-01-01

    An in-depth knowledge of how to configure Cisco IP network security is a MUST for anyone working in today''s internetworked world"There''s no question that attacks on enterprise networks are increasing in frequency and sophistication..."-Mike Fuhrman, Cisco Systems Manager, Security ConsultingManaging Cisco Network Security, Second Edition offers updated and revised information covering many of Cisco''s security products that provide protection from threats, detection of network security incidents, measurement of vulnerability and policy compliance and management of security policy across an extended organization. These are the tools that network administrators have to mount defenses against threats. Chapters also cover the improved functionality and ease of the Cisco Secure Policy Manger software used by thousands of small-to-midsized businesses and a special section on the Cisco Aironet Wireless Security Solutions.Security from a real-world perspectiveKey coverage of the new technologies offered by the Cisc...

  19. Hierarchical Network Design

    DEFF Research Database (Denmark)

    Thomadsen, Tommy

    2005-01-01

    design. The papers have all been submitted for journals, and except for two papers, are awaiting review. The papers are mostly concerned with optimal methods and, in a few cases, heuristics for designing hierarchical and ring networks. All papers develop bounds which are used in the optimal methods...... danne grundlag for et studie af design af hierarkiske netværk. Afhandlings vigtigste bidrag best ar af syv artikler, der er inkluderet i appendiks. Artiklerne handler om design af hierarkisk netværk og ring netværk. Artiklerne er alle indsendt til videnskablige journaler og afventer bedømmelse, bortset......Communication networks are immensely important today, since both companies and individuals use numerous services that rely on them. This thesis considers the design of hierarchical (communication) networks. Hierarchical networks consist of layers of networks and are well-suited for coping...

  20. Network ties and survival

    DEFF Research Database (Denmark)

    Acheampong, George; Narteh, Bedman; Rand, John

    2017-01-01

    Poultry farming has been touted as one of the major ways by which poverty can be reduced in low-income economies like Ghana. Yet, anecdotally there is a high failure rate among these poultry farms. This current study seeks to understand the relationship between network ties and survival chances...... of small commercial poultry farms (SCPFs). We utilize data from a 2-year network survey of SCPFs in rural Ghana. The survival of these poultry farms are modelled using a lagged probit model of farms that persisted from 2014 into 2015. We find that network ties are important to the survival chances...... but this probability reduces as the number of industry ties increases but moderation with dynamic capability of the firm reverses this trend. Our findings show that not all network ties aid survival and therefore small commercial poultry farmers need to be circumspect in the network ties they cultivate and develop....

  1. Collective network routing

    Science.gov (United States)

    Hoenicke, Dirk

    2014-12-02

    Disclosed are a unified method and apparatus to classify, route, and process injected data packets into a network so as to belong to a plurality of logical networks, each implementing a specific flow of data on top of a common physical network. The method allows to locally identify collectives of packets for local processing, such as the computation of the sum, difference, maximum, minimum, or other logical operations among the identified packet collective. Packets are injected together with a class-attribute and an opcode attribute. Network routers, employing the described method, use the packet attributes to look-up the class-specific route information from a local route table, which contains the local incoming and outgoing directions as part of the specifically implemented global data flow of the particular virtual network.

  2. Minimum cost connection networks

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    In the present paper we consider the allocation of cost in connection networks. Agents have connection demands in form of pairs of locations they want to be connected. Connections between locations are costly to build. The problem is to allocate costs of networks satisfying all connection demands....... We use three axioms to characterize allocation rules that truthfully implement cost minimizing networks satisfying all connection demands in a game where: (1) a central planner announces an allocation rule and a cost estimation rule; (2) every agent reports her own connection demand as well as all...... connection costs; and, (3) the central planner selects a cost minimizing network satisfying reported connection demands based on estimated connection costs and allocates true connection costs of the selected network....

  3. Network Management of the SPLICE Computer Network.

    Science.gov (United States)

    1982-12-01

    and the Lawrence Livermore Nttionl Laboratory Octopus lietwork [Ref. 24]. Additionally, the :oiex Distributed Network Coatrol Systems 200 and 330...Alexander A., litftqiifivl 93 24. University of Calif~cnia Lavr i ce LJ~vermoce Laboratory Letter Wloe Requa): to -aptN -1raq. Ope, maya & Postgraduaate

  4. Innovation networks : Managing the networked organization

    NARCIS (Netherlands)

    Aalbers, Rick; Dolfsma, Wilfred

    2015-01-01

    Organizations are complex social systems that are not easy to understand, yet they must be managed if a company is to succeed. This book explains networks and how managers and organizations can navigate them to produce successful strategic innovation outcomes. Although managers are increasingly

  5. Tinnitus: Network pathophysiology-network pharmacology

    Directory of Open Access Journals (Sweden)

    Ana Belen eElgoyhen

    2012-01-01

    Full Text Available Tinnitus, the phantom perception of sound, is a prevalent disorder. One in 10 adults has clinically significant subjective tinnitus, and for 1 in 100, tinnitus severely affects their quality of life. Despite the significant unmet clinical need for a safe and effective drug targeting tinnitus relief, there is currently not a single FDA-approved drug on the market. The search for drugs that target tinnitus is hampered by the lack of a deep knowledge of the underlying neural substrates of this pathology. Recent studies are increasingly demonstrating that, as described for other central nervous system disorders, tinnitus is a pathology of brain networks. The application of graph theoretical analysis to brain networks has recently provided new information concerning their topology, their robustness and their vulnerability to attacks. Moreover, the philosophy behind drug design and pharmacotherapy in central nervous system pathologies is changing from that of magic bullets that target individual chemoreceptors or disease-causing genes into that of magic shotguns, promiscuous or dirty drugs that target disease-causing networks, also known as network pharmacology. In the present work we provide some insight into how this knowledge could be applied to tinnitus pathophysiology and pharmacotherapy.

  6. Network of networks in Linux operating system

    Science.gov (United States)

    Wang, Haoqin; Chen, Zhen; Xiao, Guanping; Zheng, Zheng

    2016-04-01

    Operating system represents one of the most complex man-made systems. In this paper, we analyze Linux Operating System (LOS) as a complex network via modeling functions as nodes and function calls as edges. It is found that for the LOS network and modularized components within it, the out-degree follows an exponential distribution and the in-degree follows a power-law distribution. For better understanding the underlying design principles of LOS, we explore the coupling correlations of components in LOS from aspects of topology and function. The result shows that the component for device drivers has a strong manifestation in topology while a weak manifestation in function. However, the component for process management shows the contrary phenomenon. Moreover, in an effort to investigate the impact of system failures on networks, we make a comparison between the networks traced from normal and failure status of LOS. This leads to a conclusion that the failure will change function calls which should be executed in normal status and introduce new function calls in the meanwhile.

  7. Networks : Empowering Communities through Telecentre Networking

    International Development Research Centre (IDRC) Digital Library (Canada)

    In 2006 IDRC's telecentre.org commissioned a survey entitled, Telecentre Scoping Study in North Africa and the Middle East (103537), the first of its kind in the region. The study revealed that although there are no formal telecentre networking activities in the region, those countries in which telecentres are strongest - Egypt, ...

  8. Mobility Network and Safety

    Directory of Open Access Journals (Sweden)

    Adriana Galderisi

    2010-04-01

    Full Text Available Mobility network is crucial for ensuring territorial safety with respect to natural and technological hazards. They represent a basic support to community’s everyday life although being exposed elements often characterized by high vulnerability to different hazards and, in the meanwhile, strategic equipments for emergency management. Physical damages or the lack in functioning of those networks may greatly increase the loss of human lives caused by hazardous events as well as produce relevant economic damages at medium and long term. Although the relevance of the mobility networks in assuring territorial safety is at present largely recognized, risk analyses have been long focused on buildings’ vulnerability or, even where they have paid attention to mobility network, they have been mainly focused on the physical damages that a given hazard could may induce on individual elements of such network. It is recent the awareness that mobility network represents a system, characterized by relevant interdependences both among its elements and among network infrastructures and urban systems. Based on these assumptions, this paper points out the heterogeneous aspects of the mobility network vulnerability and their relevance in increasing the overall territorial or urban vulnerability to hazardous events. Therefore, an in-depth investigation of the concept of mobility network vulnerability is provided, in order to highlight the aspects mostly investigated and more recent research perspectives. Finally, a case study in the Campania Region is presented in order to point out how traditional risk analyses, generally referred to individual hazards, can sometimes led to invest in the mobility network improvement or development which, targeted to increase the security of a territory result, on the opposite, in an increase of the territorial vulnerability.

  9. A Network Traffic Control Enhancement Approach over Bluetooth Networks

    DEFF Research Database (Denmark)

    Son, L.T.; Schiøler, Henrik; Madsen, Ole Brun

    2003-01-01

    This paper analyzes network traffic control issues in Bluetooth data networks as convex optimization problem. We formulate the problem of maximizing of total network flows and minimizing the costs of flows. An adaptive distributed network traffic control scheme is proposed as an approximated...... solution of the stated optimization problem that satisfies quality of service requirements and topologically induced constraints in Bluetooth networks, such as link capacity and node resource limitations. The proposed scheme is decentralized and complies with frequent changes of topology as well...... as capacity limitations and flow requirements in the network. Simulation shows that the performance of Bluetooth networks could be improved by applying the adaptive distributed network traffic control scheme...

  10. Extracting information from multiplex networks.

    Science.gov (United States)

    Iacovacci, Jacopo; Bianconi, Ginestra

    2016-06-01

    Multiplex networks are generalized network structures that are able to describe networks in which the same set of nodes are connected by links that have different connotations. Multiplex networks are ubiquitous since they describe social, financial, engineering, and biological networks as well. Extending our ability to analyze complex networks to multiplex network structures increases greatly the level of information that is possible to extract from big data. For these reasons, characterizing the centrality of nodes in multiplex networks and finding new ways to solve challenging inference problems defined on multiplex networks are fundamental questions of network science. In this paper, we discuss the relevance of the Multiplex PageRank algorithm for measuring the centrality of nodes in multilayer networks and we characterize the utility of the recently introduced indicator function Θ̃(S) for describing their mesoscale organization and community structure. As working examples for studying these measures, we consider three multiplex network datasets coming for social science.

  11. Neural Networks: Implementations and Applications

    NARCIS (Netherlands)

    Vonk, E.; Veelenturf, L.P.J.; Jain, L.C.

    1996-01-01

    Artificial neural networks, also called neural networks, have been used successfully in many fields including engineering, science and business. This paper presents the implementation of several neural network simulators and their applications in character recognition and other engineering areas

  12. Models of educational institutions' networking

    OpenAIRE

    Shilova Olga Nikolaevna

    2015-01-01

    The importance of educational institutions' networking in modern sociocultural conditions and a definition of networking in education are presented in the article. The results of research levels, methods and models of educational institutions' networking are presented and substantially disclosed.

  13. Articulation points in complex networks

    Science.gov (United States)

    Tian, Liang; Bashan, Amir; Shi, Da-Ning; Liu, Yang-Yu

    2017-01-01

    An articulation point in a network is a node whose removal disconnects the network. Those nodes play key roles in ensuring connectivity of many real-world networks, from infrastructure networks to protein interaction networks and terrorist communication networks. Despite their fundamental importance, a general framework of studying articulation points in complex networks is lacking. Here we develop analytical tools to study key issues pertinent to articulation points, such as the expected number of them and the network vulnerability against their removal, in an arbitrary complex network. We find that a greedy articulation point removal process provides us a different perspective on the organizational principles of complex networks. Moreover, this process results in a rich phase diagram with two fundamentally different types of percolation transitions. Our results shed light on the design of more resilient infrastructure networks and the effective destruction of terrorist communication networks.

  14. Flow whitelisting in SCADA networks

    DEFF Research Database (Denmark)

    Barbosa, Rafael Ramos Regis; Sadre, Ramin; Pras, Aiko

    2013-01-01

    Supervisory control and data acquisition (SCADA) networks are commonly deployed in large industrial facilities. Modern SCADA networks are becoming more vulnerable to cyber attacks due to the common use of standard communications protocols and increased interconnections with corporate networks and...

  15. Flow whitelisting in SCADA networks

    NARCIS (Netherlands)

    Barbosa, R.R.R.; Sadre, R.; Pras, Aiko

    2013-01-01

    Supervisory control and data acquisition (SCADA) networks are commonly deployed in large industrial facilities. Modern SCADA networks are becoming more vulnerable to cyber attacks due to the common use of standard communications protocols and increased interconnections with corporate networks and

  16. Decomposition of Network Communication Games

    NARCIS (Netherlands)

    Dietzenbacher, Bas; Borm, Peter; Hendrickx, Ruud

    2015-01-01

    Using network control structures this paper introduces network communication games as a generalization of vertex games and edge games corresponding to communication situations and studies their decomposition into unanimity games. We obtain a relation between the dividends of the network

  17. Leadership Networking Connect, Collaborate, Create

    CERN Document Server

    (CCL), Center for Creative Leadership; Baldwin, David

    2011-01-01

    Networking is essential to effective leadership in today's organizations. Leaders who are skilled networkers have access to people, information, and resources to help solve problems and create opportunities. Leaders who neglect their networks are missing out on a critical component of their role as leaders. This book will help leaders take a new view of networking and provide insight into how to enhance their networks and become effective at leadership networking.

  18. Network coding at different layers in wireless networks

    CERN Document Server

    2016-01-01

    This book focuses on how to apply network coding at different layers in wireless networks – including MAC, routing, and TCP – with special focus on cognitive radio networks. It discusses how to select parameters in network coding (e.g., coding field, number of packets involved, and redundant information ration) in order to be suitable for the varying wireless environments. The book explores how to deploy network coding in MAC to improve network performance and examines joint network coding with opportunistic routing to improve the successful rate of routing. In regards to TCP and network coding, the text considers transport layer protocol working with network coding to overcome the transmission error rate, particularly with how to use the ACK feedback of TCP to enhance the efficiency of network coding. The book pertains to researchers and postgraduate students, especially whose interests are in opportunistic routing and TCP in cognitive radio networks.

  19. Optical Network Testbeds Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Joe Mambretti

    2007-06-01

    This is the summary report of the third annual Optical Networking Testbed Workshop (ONT3), which brought together leading members of the international advanced research community to address major challenges in creating next generation communication services and technologies. Networking research and development (R&D) communities throughout the world continue to discover new methods and technologies that are enabling breakthroughs in advanced communications. These discoveries are keystones for building the foundation of the future economy, which requires the sophisticated management of extremely large qualities of digital information through high performance communications. This innovation is made possible by basic research and experiments within laboratories and on specialized testbeds. Initial network research and development initiatives are driven by diverse motives, including attempts to solve existing complex problems, the desire to create powerful new technologies that do not exist using traditional methods, and the need to create tools to address specific challenges, including those mandated by large scale science or government agency mission agendas. Many new discoveries related to communications technologies transition to wide-spread deployment through standards organizations and commercialization. These transition paths allow for new communications capabilities that drive many sectors of the digital economy. In the last few years, networking R&D has increasingly focused on advancing multiple new capabilities enabled by next generation optical networking. Both US Federal networking R&D and other national R&D initiatives, such as those organized by the National Institute of Information and Communications Technology (NICT) of Japan are creating optical networking technologies that allow for new, powerful communication services. Among the most promising services are those based on new types of multi-service or hybrid networks, which use new optical networking

  20. SBA Network Components & Software Inventory

    Data.gov (United States)

    Small Business Administration — SBA’s Network Components & Software Inventory contains a complete inventory of all devices connected to SBA’s network including workstations, servers, routers,...

  1. Assimilation Dynamic Network (ADN) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Assimilation Dynamic Network (ADN) is a dynamic inter-processor communication network that spans heterogeneous processor architectures, unifying components,...

  2. G-Networks with Adders

    National Research Council Canada - National Science Library

    Jean-Michel Fourneau; Erol Gelenbe

    2017-01-01

    .... Composed of service stations where customers receive service, and then move to another service station till they leave the network, queueing networks are based on probabilistic assumptions concerning...

  3. Energy efficiency in wireless networks

    CERN Document Server

    Jumira, Oswald

    2013-01-01

    The last decade has witnessed an unprecedented development and growth in global wireless communications systems, technologies and network "traffic" generated over network infrastructures.This book presents state-of-the-art energy-efficient techniques, designs and implementations that pertain to wireless communication networks such as cellular networks, wireless local area networks (WLANs) and wireless ad hoc networks (WAHNs) including mobile ad hoc networks (MANETs), and wireless sensor networks (WSNs) as they are deployed across the world to facilitate "always on" reliable high-speed

  4. Robustness of airline route networks

    Science.gov (United States)

    Lordan, Oriol; Sallan, Jose M.; Escorihuela, Nuria; Gonzalez-Prieto, David

    2016-03-01

    Airlines shape their route network by defining their routes through supply and demand considerations, paying little attention to network performance indicators, such as network robustness. However, the collapse of an airline network can produce high financial costs for the airline and all its geographical area of influence. The aim of this study is to analyze the topology and robustness of the network route of airlines following Low Cost Carriers (LCCs) and Full Service Carriers (FSCs) business models. Results show that FSC hubs are more central than LCC bases in their route network. As a result, LCC route networks are more robust than FSC networks.

  5. Launch Control Network Engineer

    Science.gov (United States)

    Medeiros, Samantha

    2017-01-01

    The Spaceport Command and Control System (SCCS) is being built at the Kennedy Space Center in order to successfully launch NASA’s revolutionary vehicle that allows humans to explore further into space than ever before. During my internship, I worked with the Network, Firewall, and Hardware teams that are all contributing to the huge SCCS network project effort. I learned the SCCS network design and the several concepts that are running in the background. I also updated and designed documentation for physical networks that are part of SCCS. This includes being able to assist and build physical installations as well as configurations. I worked with the network design for vehicle telemetry interfaces to the Launch Control System (LCS); this allows the interface to interact with other systems at other NASA locations. This network design includes the Space Launch System (SLS), Interim Cryogenic Propulsion Stage (ICPS), and the Orion Multipurpose Crew Vehicle (MPCV). I worked on the network design and implementation in the Customer Avionics Interface Development and Analysis (CAIDA) lab.

  6. Networked Microgrids Scoping Study

    Energy Technology Data Exchange (ETDEWEB)

    Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dobriansky, Larisa [General MicroGrids, San Diego, CA (United States); Glover, Steve [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Liu, Chen-Ching [Washington State Univ., Pullman, WA (United States); Looney, Patrick [Brookhaven National Lab. (BNL), Upton, NY (United States); Mashayekh, Salman [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Pratt, Annabelle [National Renewable Energy Lab. (NREL), Golden, CO (United States); Schneider, Kevin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stadler, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Starke, Michael [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Jianhui [Argonne National Lab. (ANL), Argonne, IL (United States); Yue, Meng [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-12-05

    Much like individual microgrids, the range of opportunities and potential architectures of networked microgrids is very diverse. The goals of this scoping study are to provide an early assessment of research and development needs by examining the benefits of, risks created by, and risks to networked microgrids. At this time there are very few, if any, examples of deployed microgrid networks. In addition, there are very few tools to simulate or otherwise analyze the behavior of networked microgrids. In this setting, it is very difficult to evaluate networked microgrids systematically or quantitatively. At this early stage, this study is relying on inputs, estimations, and literature reviews by subject matter experts who are engaged in individual microgrid research and development projects, i.e., the authors of this study The initial step of the study gathered input about the potential opportunities provided by networked microgrids from these subject matter experts. These opportunities were divided between the subject matter experts for further review. Part 2 of this study is comprised of these reviews. Part 1 of this study is a summary of the benefits and risks identified in the reviews in Part 2 and synthesis of the research needs required to enable networked microgrids.

  7. Simulated Associating Polymer Networks

    Science.gov (United States)

    Billen, Joris

    Telechelic associating polymer networks consist of polymer chains terminated by endgroups that have a different chemical composition than the polymer backbone. When dissolved in a solution, the endgroups cluster together to form aggregates. At low temperature, a strongly connected reversible network is formed and the system behaves like a gel. Telechelic networks are of interest since they are representative for biopolymer networks (e.g. F-actin) and are widely used in medical applications (e.g. hydrogels for tissue engineering, wound dressings) and consumer products (e.g. contact lenses, paint thickeners). In this thesis such systems are studied by means of a molecular dynamics/Monte Carlo simulation. At first, the system in rest is studied by means of graph theory. The changes in network topology upon cooling to the gel state, are characterized. Hereto an extensive study of the eigenvalue spectrum of the gel network is performed. As a result, an in-depth investigation of the eigenvalue spectra for spatial ER, scale-free, and small-world networks is carried out. Next, the gel under the application of a constant shear is studied, with a focus on shear banding and the changes in topology under shear. Finally, the relation between the gel transition and percolation is discussed.

  8. Balanced Centrality of Networks

    Science.gov (United States)

    Sciriha, Irene

    2014-01-01

    There is an age-old question in all branches of network analysis. What makes an actor in a network important, courted, or sought? Both Crossley and Bonacich contend that rather than its intrinsic wealth or value, an actor's status lies in the structures of its interactions with other actors. Since pairwise relation data in a network can be stored in a two-dimensional array or matrix, graph theory and linear algebra lend themselves as great tools to gauge the centrality (interpreted as importance, power, or popularity, depending on the purpose of the network) of each actor. We express known and new centralities in terms of only two matrices associated with the network. We show that derivations of these expressions can be handled exclusively through the main eigenvectors (not orthogonal to the all-one vector) associated with the adjacency matrix. We also propose a centrality vector (SWIPD) which is a linear combination of the square, walk, power, and degree centrality vectors with weightings of the various centralities depending on the purpose of the network. By comparing actors' scores for various weightings, a clear understanding of which actors are most central is obtained. Moreover, for threshold networks, the (SWIPD) measure turns out to be independent of the weightings. PMID:27437494

  9. A quantum access network.

    Science.gov (United States)

    Fröhlich, Bernd; Dynes, James F; Lucamarini, Marco; Sharpe, Andrew W; Yuan, Zhiliang; Shields, Andrew J

    2013-09-05

    The theoretically proven security of quantum key distribution (QKD) could revolutionize the way in which information exchange is protected in the future. Several field tests of QKD have proven it to be a reliable technology for cryptographic key exchange and have demonstrated nodal networks of point-to-point links. However, until now no convincing answer has been given to the question of how to extend the scope of QKD beyond niche applications in dedicated high security networks. Here we introduce and experimentally demonstrate the concept of a 'quantum access network': based on simple and cost-effective telecommunication technologies, the scheme can greatly expand the number of users in quantum networks and therefore vastly broaden their appeal. We show that a high-speed single-photon detector positioned at a network node can be shared between up to 64 users for exchanging secret keys with the node, thereby significantly reducing the hardware requirements for each user added to the network. This point-to-multipoint architecture removes one of the main obstacles restricting the widespread application of QKD. It presents a viable method for realizing multi-user QKD networks with efficient use of resources, and brings QKD closer to becoming a widespread technology.

  10. Towards Optimal Transport Networks

    Directory of Open Access Journals (Sweden)

    Erik P. Vargo

    2010-08-01

    Full Text Available Our ultimate goal is to design transportation net- works whose dynamic performance metrics (e.g. pas- senger throughput, passenger delay, and insensitivity to weather disturbances are optimized. Here the fo- cus is on optimizing static features of the network that are known to directly affect the network dynamics. First, we present simulation results which support a connection between maximizing the first non-trivial eigenvalue of a network's Laplacian and superior air- port network performance. Then, we explore the ef- fectiveness of a tabu search heuristic for optimizing this metric by comparing experimental results to the- oretical upper bounds. We also consider generating upper bounds on a network's algebraic connectivity via the solution of semidefinite programming (SDP relaxations. A modification of an existing subgraph extraction algorithm is implemented to explore the underlying regional structures in the U.S. airport net- work, with the hope that the resulting localized struc- tures can be optimized independently and reconnected via a "backbone" network to achieve superior network performance.

  11. Scalable Virtual Network Mapping Algorithm for Internet-Scale Networks

    Science.gov (United States)

    Yang, Qiang; Wu, Chunming; Zhang, Min

    The proper allocation of network resources from a common physical substrate to a set of virtual networks (VNs) is one of the key technical challenges of network virtualization. While a variety of state-of-the-art algorithms have been proposed in an attempt to address this issue from different facets, the challenge still remains in the context of large-scale networks as the existing solutions mainly perform in a centralized manner which requires maintaining the overall and up-to-date information of the underlying substrate network. This implies the restricted scalability and computational efficiency when the network scale becomes large. This paper tackles the virtual network mapping problem and proposes a novel hierarchical algorithm in conjunction with a substrate network decomposition approach. By appropriately transforming the underlying substrate network into a collection of sub-networks, the hierarchical virtual network mapping algorithm can be carried out through a global virtual network mapping algorithm (GVNMA) and a local virtual network mapping algorithm (LVNMA) operated in the network central server and within individual sub-networks respectively with their cooperation and coordination as necessary. The proposed algorithm is assessed against the centralized approaches through a set of numerical simulation experiments for a range of network scenarios. The results show that the proposed hierarchical approach can be about 5-20 times faster for VN mapping tasks than conventional centralized approaches with acceptable communication overhead between GVNCA and LVNCA for all examined networks, whilst performs almost as well as the centralized solutions.

  12. Attractor metabolic networks.

    Science.gov (United States)

    De la Fuente, Ildefonso M; Cortes, Jesus M; Pelta, David A; Veguillas, Juan

    2013-01-01

    The experimental observations and numerical studies with dissipative metabolic networks have shown that cellular enzymatic activity self-organizes spontaneously leading to the emergence of a Systemic Metabolic Structure in the cell, characterized by a set of different enzymatic reactions always locked into active states (metabolic core) while the rest of the catalytic processes are only intermittently active. This global metabolic structure was verified for Escherichia coli, Helicobacter pylori and Saccharomyces cerevisiae, and it seems to be a common key feature to all cellular organisms. In concordance with these observations, the cell can be considered a complex metabolic network which mainly integrates a large ensemble of self-organized multienzymatic complexes interconnected by substrate fluxes and regulatory signals, where multiple autonomous oscillatory and quasi-stationary catalytic patterns simultaneously emerge. The network adjusts the internal metabolic activities to the external change by means of flux plasticity and structural plasticity. In order to research the systemic mechanisms involved in the regulation of the cellular enzymatic activity we have studied different catalytic activities of a dissipative metabolic network under different external stimuli. The emergent biochemical data have been analysed using statistical mechanic tools, studying some macroscopic properties such as the global information and the energy of the system. We have also obtained an equivalent Hopfield network using a Boltzmann machine. Our main result shows that the dissipative metabolic network can behave as an attractor metabolic network. We have found that the systemic enzymatic activities are governed by attractors with capacity to store functional metabolic patterns which can be correctly recovered from specific input stimuli. The network attractors regulate the catalytic patterns, modify the efficiency in the connection between the multienzymatic complexes, and stably

  13. Attractor metabolic networks.

    Directory of Open Access Journals (Sweden)

    Ildefonso M De la Fuente

    Full Text Available BACKGROUND: The experimental observations and numerical studies with dissipative metabolic networks have shown that cellular enzymatic activity self-organizes spontaneously leading to the emergence of a Systemic Metabolic Structure in the cell, characterized by a set of different enzymatic reactions always locked into active states (metabolic core while the rest of the catalytic processes are only intermittently active. This global metabolic structure was verified for Escherichia coli, Helicobacter pylori and Saccharomyces cerevisiae, and it seems to be a common key feature to all cellular organisms. In concordance with these observations, the cell can be considered a complex metabolic network which mainly integrates a large ensemble of self-organized multienzymatic complexes interconnected by substrate fluxes and regulatory signals, where multiple autonomous oscillatory and quasi-stationary catalytic patterns simultaneously emerge. The network adjusts the internal metabolic activities to the external change by means of flux plasticity and structural plasticity. METHODOLOGY/PRINCIPAL FINDINGS: In order to research the systemic mechanisms involved in the regulation of the cellular enzymatic activity we have studied different catalytic activities of a dissipative metabolic network under different external stimuli. The emergent biochemical data have been analysed using statistical mechanic tools, studying some macroscopic properties such as the global information and the energy of the system. We have also obtained an equivalent Hopfield network using a Boltzmann machine. Our main result shows that the dissipative metabolic network can behave as an attractor metabolic network. CONCLUSIONS/SIGNIFICANCE: We have found that the systemic enzymatic activities are governed by attractors with capacity to store functional metabolic patterns which can be correctly recovered from specific input stimuli. The network attractors regulate the catalytic patterns

  14. COalitions in COOperation Networks (COCOON): Social Network Analysis and Game Theory to Enhance Cooperation Networks

    NARCIS (Netherlands)

    Sie, Rory

    2012-01-01

    Sie, R. L. L. (2012). COalitions in COOperation Networks (COCOON): Social Network Analysis and Game Theory to Enhance Cooperation Networks (Unpublished doctoral dissertation). September, 28, 2012, Open Universiteit in the Netherlands (CELSTEC), Heerlen, The Netherlands.

  15. The Space Mobile Network

    Science.gov (United States)

    Israel, David

    2017-01-01

    The definition and development of the next generation space communications and navigation architecture is underway. The primary goals are to remove communications and navigations constraints from missions and to enable increased autonomy. The Space Mobile Network (SMN) is an architectural concept that includes new technology and operations that will provide flight systems with an similar user experience to terrestrial wireless mobile networks. This talk will describe the SMN and its proposed new features, such as Disruption Tolerant Networking (DTN), optical communications, and User Initiated Services (UIS).

  16. Wireless rechargeable sensor networks

    CERN Document Server

    Yang, Yuanyuan

    2015-01-01

    This SpringerBrief provides a concise guide to applying wireless energy transfer techniques in traditional battery-powered sensor networks. It examines the benefits and challenges of wireless power including efficiency and reliability. The authors build a wireless rechargeable sensor networks from scratch and aim to provide perpetual network operation. Chapters cover a wide range of topics from the collection of energy information and recharge scheduling to joint design with typical sensing applications such as data gathering. Problems are approached using a natural combination of probability

  17. BES Science Network Requirements

    Energy Technology Data Exchange (ETDEWEB)

    Biocca, Alan; Carlson, Rich; Chen, Jackie; Cotter, Steve; Tierney, Brian; Dattoria, Vince; Davenport, Jim; Gaenko, Alexander; Kent, Paul; Lamm, Monica; Miller, Stephen; Mundy, Chris; Ndousse, Thomas; Pederson, Mark; Perazzo, Amedeo; Popescu, Razvan; Rouson, Damian; Sekine, Yukiko; Sumpter, Bobby; Dart, Eli; Wang, Cai-Zhuang -Z; Whitelam, Steve; Zurawski, Jason

    2011-02-01

    The Energy Sciences Network (ESnet) is the primary provider of network connectivityfor the US Department of Energy Office of Science (SC), the single largest supporter of basic research in the physical sciences in the United States. In support of the Office ofScience programs, ESnet regularly updates and refreshes its understanding of the networking requirements of the instruments, facilities, scientists, and science programs that it serves. This focus has helped ESnet to be a highly successful enabler of scientific discovery for over 20 years.

  18. The Photograph as Network

    DEFF Research Database (Denmark)

    Wiegand, Frauke Katharina

    2017-01-01

    tool for reading the net-work of images. The case is two visitor snapshots at the photographic exhibition, ‘The Story of Soweto’, in the famous Regina Mundi Church in Soweto, South Africa. I demonstrate that, when slightly adjusted for research engaging with visual materials, Latourian concepts......Inspired by actor-network theory (ANT), this article develops a theoretical framework to grasp the dynamic visual work of memory. It introduces three sensitizing concepts of actor-network methodology, namely entanglement, relationality and traceability, and operationalizes them in a methodological...

  19. Beyond the networks

    DEFF Research Database (Denmark)

    Andreasen, Manja Hoppe; Møller-Jensen, Lasse

    2016-01-01

    through applications, co-financing of network extensions as well as lobbying efforts towards urban authorities and service providers. The formal service providers primarily take a reactive role, responding to demand, requests and political pressure from residents. Post-settlement network extensions...... are often complicated and impeded by costly and cumbersome land-acquisition processes, and because of the reactive and often piecemeal approach to network extensions, society may be missing out on potential benefits of scale. The way urban services work also means that the provision of services...

  20. Design of survivable networks

    CERN Document Server

    Stoer, Mechthild

    1992-01-01

    The problem of designing a cost-efficient network that survives the failure of one or more nodes or edges of the network is critical to modern telecommunications engineering. The method developed in this book is designed to solve such problems to optimality. In particular, a cutting plane approach is described, based on polyhedral combinatorics, that is ableto solve real-world problems of this type in short computation time. These results are of interest for practitioners in the area of communication network design. The book is addressed especially to the combinatorial optimization community, but also to those who want to learn polyhedral methods. In addition, interesting new research problemsare formulated.

  1. Wireless network pricing

    CERN Document Server

    Huang, Jianwei

    2013-01-01

    Today's wireless communications and networking practices are tightly coupled with economic considerations, to the extent that it is almost impossible to make a sound technology choice without understanding the corresponding economic implications. This book aims at providing a foundational introduction on how microeconomics, and pricing theory in particular, can help us to understand and build better wireless networks. The book can be used as lecture notes for a course in the field of network economics, or a reference book for wireless engineers and applied economists to understand how pricing

  2. Introduction to network emulation

    CERN Document Server

    Beuran, Razvan

    2012-01-01

    ""Since network emulation permits investigation of how higher-level protocols interact with the underlying network behaviour, it will be of particular interest to anyone tasked with designing and rolling out new applications and services, especially those aimed at wireless transport. This book represents a comprehensive survey of the current state of the art. It will give the readers a good sense of the various techniques available, allowing them to make an informed decision as to which are appropriate to their particular problem.""-Dr. Neil Davies - Predictable Network Solutions, UK""The Inte

  3. Multilayer Social Networks

    DEFF Research Database (Denmark)

    Dickison, Mark; Magnani, Matteo; Rossi, Luca

    social network systems, the evolution of interconnected social networks, and dynamic processes such as information spreading. A single real dataset is used to illustrate the concepts presented throughout the book, demonstrating both the practical utility and the potential shortcomings of the various...... research communities, leading to the development of several independent models and methods to deal with the same set of problems. This book unifies and consolidates existing practical and theoretical knowledge on multilayer networks including data collection and analysis, modeling, and mining of multilayer...

  4. Body Area Networks

    Directory of Open Access Journals (Sweden)

    G. Prabhakara Reddy

    2013-01-01

    Full Text Available Recent technological advances in integrated circuits, wireless networks, and physiological sensing have enabled miniature, lightweight, low power, intelligent monitoring devices to be integrated into a Body Area Network (BAN. This new type of technology hold much promise for future patient health monitoring. BANs promise inexpensive, unobtrusive, and unsupervised ambulatory monitoring during normal daily activities for long periods of time. However, in order for BANs to become ubiquitous and affordable, a number of challenging issues must be resolved, such as integration, standardisation, system design, customisation, security and privacy, and social issues. This paper presents an overview of many of these issues and indeed the background and rationale of body area networks.

  5. Self-organizing networks

    DEFF Research Database (Denmark)

    Marchetti, Nicola; Prasad, Neeli R.; Johansson, Johan

    2010-01-01

    In this paper, a general overview of Self-Organizing Networks (SON), and the rationale and state-of-the-art of wireless SON are first presented. The technical and business requirements are then briefly treated, and the research challenges within the field of SON are highlighted. Thereafter......, the relation between SON and Cognitive Networks (CN) is covered. At last, the application of Algorithmic Information Theory (AIT) as a possible theoretical tool to support SON in addressing the growing complexity of networks is discussed....

  6. Data Exchange Network

    DEFF Research Database (Denmark)

    Grau Larsen, Anton; Ellersgaard, Christoph

    2015-01-01

    networks such as social clubs or royal events. Data were gathered through an inclusion principle, adding all potentially interesting affiliations. Procedures of name-matching and quality control are presented. Finally, the data are introduced: made available through a package for R, which enables......This article presents the extensive Danish elite network. Collected during 2012 and 2013, the data comprises 56,536 positions within 5,079 affiliations, and connects 37,750 individuals. The network consists of the largest Danish corporations, state institutions, NGO’s, and other integrative...

  7. Connected networks economy

    Energy Technology Data Exchange (ETDEWEB)

    Hamerak, K.

    1981-05-05

    Two foremost requirements for interconnected power systems are: constancy of frequency and constancy of voltage. Because there is a rigid relation between main frequency and the number of revolutions of the synchronous generators, and this leads to active load alterations in the case of frequency changes of the network, there is a need for control systems for power networks. In practice they are designed for automatic operation. For control of the number of revolutions of turbines proportional controllers are the most useful. Autocontrol also has an advantageous influence on frequency stability. Peak loads in connected networks are covered by pumping storage power plants.

  8. Evolving production network structures

    DEFF Research Database (Denmark)

    Grunow, Martin; Gunther, H.O.; Burdenik, H.

    2007-01-01

    When deciding about future production network configurations, the current structures have to be taken into account. Further, core issues such as the maturity of the products and the capacity requirements for test runs and ramp-ups must be incorporated. Our approach is based on optimization...... modelling and assigns products and capacity expansions to production sites under the above constraints. It also considers the production complexity at the individual sites and the flexibility of the network. Our implementation results for a large manufacturing network reveal substantial possible cost...... reductions compared to the traditional manual planning results of our industrial partner....

  9. Networks and Transaction Costs

    OpenAIRE

    Henning, Christian; Henningsen, Geraldine; Henningsen, Arne

    2011-01-01

    Based on the well-known fact that social networks can provide effective mechanisms that help to increase the trust level between two trade partners, we apply a simple game-theoretical framework to derive transaction costs as a high risk of opportunistic behavior in a repeated trade relation determined by the density and size of trading networks. In the empirical part of the paper we apply a two stage procedure to estimate the impact of social network structures on farm’s transaction costs obs...

  10. The EH network

    DEFF Research Database (Denmark)

    Santolini, E; Salcini, A E; Kay, B K

    1999-01-01

    . Moreover, a number of cellular ligands of the domain have been identified and demonstrated to define a complex network of protein-protein interactions in the eukaryotic cell. Interestingly, many of the EH-containing and EH-binding proteins display characteristics of endocytic "accessory" proteins......, suggesting that the principal function of the EH network is to regulate various steps in endocytosis. In addition, recent evidence suggests that the EH network might work as an "integrator" of signals controlling cellular pathways as diverse as endocytosis, nucleocytosolic export, and ultimately cell...

  11. Molecular ecological network analyses

    Directory of Open Access Journals (Sweden)

    Deng Ye

    2012-05-01

    Full Text Available Abstract Background Understanding the interaction among different species within a community and their responses to environmental changes is a central goal in ecology. However, defining the network structure in a microbial community is very challenging due to their extremely high diversity and as-yet uncultivated status. Although recent advance of metagenomic technologies, such as high throughout sequencing and functional gene arrays, provide revolutionary tools for analyzing microbial community structure, it is still difficult to examine network interactions in a microbial community based on high-throughput metagenomics data. Results Here, we describe a novel mathematical and bioinformatics framework to construct ecological association networks named molecular ecological networks (MENs through Random Matrix Theory (RMT-based methods. Compared to other network construction methods, this approach is remarkable in that the network is automatically defined and robust to noise, thus providing excellent solutions to several common issues associated with high-throughput metagenomics data. We applied it to determine the network structure of microbial communities subjected to long-term experimental warming based on pyrosequencing data of 16 S rRNA genes. We showed that the constructed MENs under both warming and unwarming conditions exhibited topological features of scale free, small world and modularity, which were consistent with previously described molecular ecological networks. Eigengene analysis indicated that the eigengenes represented the module profiles relatively well. In consistency with many other studies, several major environmental traits including temperature and soil pH were found to be important in determining network interactions in the microbial communities examined. To facilitate its application by the scientific community, all these methods and statistical tools have been integrated into a comprehensive Molecular Ecological

  12. Social Networks and Health.

    Science.gov (United States)

    Perdiaris, Christos; Chardalias, Konstantinos; Magita, Andrianna; Mechili, Aggelos E; Diomidous, Marianna

    2015-01-01

    Nowadays the social networks have been developed into an advanced communications tool, which is important for all people to contact each other. These specific networks do offer lots of options as well as plenty of advantages and disadvantages. The social websites are many in number and titles, such as the facebook, the twitter, the bandoo etc. One of the most important function-mechanisms for the social network websites, are the marketing tools. The future goal is suggested to be the evolution of these programs. The development of these applications, which is going to lead into a new era for the social digital communication between the internet users, all around the globe.

  13. Quantifying randomness in real networks

    Science.gov (United States)

    Orsini, Chiara; Dankulov, Marija M.; Colomer-de-Simón, Pol; Jamakovic, Almerima; Mahadevan, Priya; Vahdat, Amin; Bassler, Kevin E.; Toroczkai, Zoltán; Boguñá, Marián; Caldarelli, Guido; Fortunato, Santo; Krioukov, Dmitri

    2015-10-01

    Represented as graphs, real networks are intricate combinations of order and disorder. Fixing some of the structural properties of network models to their values observed in real networks, many other properties appear as statistical consequences of these fixed observables, plus randomness in other respects. Here we employ the dk-series, a complete set of basic characteristics of the network structure, to study the statistical dependencies between different network properties. We consider six real networks--the Internet, US airport network, human protein interactions, technosocial web of trust, English word network, and an fMRI map of the human brain--and find that many important local and global structural properties of these networks are closely reproduced by dk-random graphs whose degree distributions, degree correlations and clustering are as in the corresponding real network. We discuss important conceptual, methodological, and practical implications of this evaluation of network randomness, and release software to generate dk-random graphs.

  14. Network virtualization as enabler for cloud networking

    OpenAIRE

    Turull, Daniel

    2016-01-01

    The Internet has exponentially grown and now it is part of our everyday life. Internet services and applications rely on back-end servers that are deployed on local servers and data centers. With the growing use of data centers and cloud computing, the locations of these servers have been externalized and centralized, taking advantage of economies of scale. However, some applications need to define complex network topologies and require more than simple connectivity to the remote sites. Ther...

  15. Holographic spin networks from tensor network states

    Science.gov (United States)

    Singh, Sukhwinder; McMahon, Nathan A.; Brennen, Gavin K.

    2018-01-01

    In the holographic correspondence of quantum gravity, a global on-site symmetry at the boundary generally translates to a local gauge symmetry in the bulk. We describe one way how the global boundary on-site symmetries can be gauged within the formalism of the multiscale renormalization ansatz (MERA), in light of the ongoing discussion between tensor networks and holography. We describe how to "lift" the MERA representation of the ground state of a generic one dimensional (1D) local Hamiltonian, which has a global on-site symmetry, to a dual quantum state of a 2D "bulk" lattice on which the symmetry appears gauged. The 2D bulk state decomposes in terms of spin network states, which label a basis in the gauge-invariant sector of the bulk lattice. This decomposition is instrumental to obtain expectation values of gauge-invariant observables in the bulk, and also reveals that the bulk state is generally entangled between the gauge and the remaining ("gravitational") bulk degrees of freedom that are not fixed by the symmetry. We present numerical results for ground states of several 1D critical spin chains to illustrate that the bulk entanglement potentially depends on the central charge of the underlying conformal field theory. We also discuss the possibility of emergent topological order in the bulk using a simple example, and also of emergent symmetries in the nongauge (gravitational) sector in the bulk. More broadly, our holographic model translates the MERA, a tensor network state, to a superposition of spin network states, as they appear in lattice gauge theories in one higher dimension.

  16. Specifying Orchestrating Capability in Network Organization and Interfirm Innovation Networks

    DEFF Research Database (Denmark)

    Hu, Yimei; Sørensen, Olav Jull

    implements its blue ocean strategy through purposively build multi-level networks, i.e. an intra network organization and interfirm innovation networks. In order to get more innovation output from external and internal networks, orchestration capability is needed and should be applied both externally...

  17. Routing strategies in traffic network and phase transition in network ...

    Indian Academy of Sciences (India)

    Routing strategy; network traffic flow; hysteretic loop; phase transition from free flow state to congestion state; scale-free network; bi-stable state; traffic dynamics. PACS Nos 89.75.Hc; 89.20.Hh; 05.10.-a; 89.75.Fb. 1. Traffic dynamics based on local routing strategy on scale-free networks. Communication networks such as ...

  18. Stability from Structure : Metabolic Networks Are Unlike Other Biological Networks

    NARCIS (Netherlands)

    Van Nes, P.; Bellomo, D.; Reinders, M.J.T.; De Ridder, D.

    2009-01-01

    In recent work, attempts have been made to link the structure of biochemical networks to their complex dynamics. It was shown that structurally stable network motifs are enriched in such networks. In this work, we investigate to what extent these findings apply to metabolic networks. To this end, we

  19. Konstruksi Bayesian Network Dengan Algoritma Bayesian Association Rule Mining Network

    OpenAIRE

    Octavian

    2015-01-01

    Beberapa tahun terakhir, Bayesian Network telah menjadi konsep yang populer digunakan dalam berbagai bidang kehidupan seperti dalam pengambilan sebuah keputusan dan menentukan peluang suatu kejadian dapat terjadi. Sayangnya, pengkonstruksian struktur dari Bayesian Network itu sendiri bukanlah hal yang sederhana. Oleh sebab itu, penelitian ini mencoba memperkenalkan algoritma Bayesian Association Rule Mining Network untuk memudahkan kita dalam mengkonstruksi Bayesian Network berdasarkan data ...

  20. Emergence of robustness in networks of networks

    Science.gov (United States)

    Roth, Kevin; Morone, Flaviano; Min, Byungjoon; Makse, Hernán A.

    2017-06-01

    A model of interdependent networks of networks (NONs) was introduced recently [Proc. Natl. Acad. Sci. (USA) 114, 3849 (2017), 10.1073/pnas.1620808114] in the context of brain activation to identify the neural collective influencers in the brain NON. Here we investigate the emergence of robustness in such a model, and we develop an approach to derive an exact expression for the random percolation transition in Erdös-Rényi NONs of this kind. Analytical calculations are in agreement with numerical simulations, and highlight the robustness of the NON against random node failures, which thus presents a new robust universality class of NONs. The key aspect of this robust NON model is that a node can be activated even if it does not belong to the giant mutually connected component, thus allowing the NON to be built from below the percolation threshold, which is not possible in previous models of interdependent networks. Interestingly, the phase diagram of the model unveils particular patterns of interconnectivity for which the NON is most vulnerable, thereby marking the boundary above which the robustness of the system improves with increasing dependency connections.

  1. Logistical networking: a global storage network

    Science.gov (United States)

    Beck, Micah; Moore, Terry

    2005-01-01

    The absence of an adequate distributed storage infrastructure for data buffering has become a significant impediment to the flow of work in the wide area, data intensive collaborations that are increasingly characteristic of leading edge research in several fields. One solution to this problem, pioneered under DOE's SciDAC program, is Logistical Networking, which provides a framework for a globally scalable, maximally interoperable storage network based on the Internet Backplane Protocol (IBP). This paper provides a brief overview of the Logistical Networking (LN) architecture, the middleware developed to exploit its value, and a few of the applications that some of research communities have made of it. This work is supported by the Department of Energy SciDAC Program (esp. Terascale Supernova Initiative) under grant #DE-FC02-01ER25465 and by the Center for Gyokinetic Particle Simulation of Turbulent Transport in Burning Plasmas, under award #DE-FG02-04ER25651. Additional support was provided by the Center for Information Technology Research (CITR) of the University of Tennessee. The infrastructure used in this work was supported by the NSF CISE Research Infrastructure program, EIA-9972889 and Research Resources program EIA-022444.

  2. Network Security Visualization

    National Research Council Canada - National Science Library

    1999-01-01

    The application of interactive, three-dimensional viewing techniques to the representation of security-related, computer network status and events is expected to improve the timeliness and efficiency...

  3. Phytoplankton Monitoring Network (PMN)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Phytoplankton Monitoring Network (PMN) is a part of the National Centers for Coastal Ocean Science (NCCOS). The PMN was created as an outreach program to connect...

  4. Polyampholyte Ionomer Networks

    Science.gov (United States)

    Cavicchi, Kevin; Deng, Guodong

    Novel materials that can reversibly adapt to their environment are important as functional materials. In polymer networks, dynamic bonding of the crosslinks, which can break and reform under an external stimuli (e.g. heat or mechanical stress) are of interest for functional material properties (e.g. self-healing or shape memory) and enhanced mechanical properties (e.g. toughness, strength). One general route to introduce dynamic bonds is through non-covalent interactions. In this work, poly(butyl acrylate) networks crosslinked by vinyl benzyl tri-n-octyl ammonium/phosphonium styrene sulfonate ion pairs were prepared as model system to study the thermo-mechanical properties of polyampholyte networks as a function of the network parameters, including ion-pair chemistry and crosslink density. Results of rheological behavior, mechanical and thermal properties of these materials will be presented and compared to other ionic systems, such as ionomers with pendant counter ions.

  5. Bioprinting: Functional droplet networks

    Science.gov (United States)

    Durmus, Naside Gozde; Tasoglu, Savas; Demirci, Utkan

    2013-06-01

    Tissue-mimicking printed networks of droplets separated by lipid bilayers that can be functionalized with membrane proteins are able to spontaneously fold and transmit electrical currents along predefined paths.

  6. Network-Based Effectiveness

    National Research Council Canada - National Science Library

    Friman, Henrik

    2006-01-01

    ... (extended from Leavitt, 1965). This text identifies aspects of network-based effectiveness that can benefit from a better understanding of leadership and management development of people, procedures, technology, and organizations...

  7. Animal Telemetry Network (ATN)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data (updated daily) are from the Animal Telemetry Network (ATN) program. Begun as one of the field projects in the international Census of Marine Life, the...

  8. Autocatalysis in reaction networks.

    Science.gov (United States)

    Deshpande, Abhishek; Gopalkrishnan, Manoj

    2014-10-01

    The persistence conjecture is a long-standing open problem in chemical reaction network theory. It concerns the behavior of solutions to coupled ODE systems that arise from applying mass-action kinetics to a network of chemical reactions. The idea is that if all reactions are reversible in a weak sense, then no species can go extinct. A notion that has been found useful in thinking about persistence is that of "critical siphon." We explore the combinatorics of critical siphons, with a view toward the persistence conjecture. We introduce the notions of "drainable" and "self-replicable" (or autocatalytic) siphons. We show that: Every minimal critical siphon is either drainable or self-replicable; reaction networks without drainable siphons are persistent; and nonautocatalytic weakly reversible networks are persistent. Our results clarify that the difficulties in proving the persistence conjecture are essentially due to competition between drainable and self-replicable siphons.

  9. Lymphatic Education & Research Network

    Science.gov (United States)

    Lymphatic Education & Research Network Donate Now Become a Supporting Member X Living with LYMPHEDEMA AND Lymphatic Disease FAQs About ... December 8, 2017 11.08.2017 The Lymphatic Education & Research Network… Read More > ASRM LE&RN Combined ...

  10. Circuit switched optical networks

    DEFF Research Database (Denmark)

    Kloch, Allan

    2003-01-01

    -connects can substitute the electrical nodes that today connect the installed optical fibres. This substitution will enable a massive increase in capacity since the bandwidth of the individual wavelength channels can be increased drastically when the electronic bit processing can be omitted. Furthermore......, it is expected that the optical solution will offer an economical benefit for hight bit rate networks. This thesis begins with a discussion of the expected impact on communications systems from the rapidly growing IP traffic, which is expected to become the dominant source for traffic. IP traffic has some...... characteristics, which are best supported by an optical network. The interest for such an optical network is exemplified by the formation of the ACTS OPEN project which aim was to investigate the feasibility of an optical network covering Europe. Part of the work presented in this thesis is carried out within...

  11. Networks / Tiia Johannson

    Index Scriptorium Estoniae

    Johannson, Tiia, 1965-2002

    2002-01-01

    11.-25. IV Kanadas Newfoundlandi saare pealinnas St. Johnis toimunud meediakunstifestivalist "Networks" alapealkirjaga "A Placeless Space". Kuraator Andrea Cooper. Pikemalt Liz Pickardi installatsioonist "Museum of the Mind". Virtuaalse ruumina kasutati virtuaalmaailma "OnLive Traveller"

  12. Delay tolerant networks

    CERN Document Server

    Gao, Longxiang; Luan, Tom H

    2015-01-01

    This brief presents emerging and promising communication methods for network reliability via delay tolerant networks (DTNs). Different from traditional networks, DTNs possess unique features, such as long latency and unstable network topology. As a result, DTNs can be widely applied to critical applications, such as space communications, disaster rescue, and battlefield communications. The brief provides a complete investigation of DTNs and their current applications, from an overview to the latest development in the area. The core issue of data forward in DTNs is tackled, including the importance of social characteristics, which is an essential feature if the mobile devices are used for human communication. Security and privacy issues in DTNs are discussed, and future work is also discussed.

  13. Managing collaborative innovation networks

    DEFF Research Database (Denmark)

    Stevens, Vidar; Agger, Annika

    2017-01-01

    . Empirical research on the management of collaborative policy innovation processes is, however, scarce. Therefore, we review in this article a case to add new insights to the causal link between collaboration, management, and innovation. Specifically, we examine the management strategies which helped......Collaborative innovation networks are increasingly used as vehicles for fostering innovative policy solutions. However, scholars have noted that the extent to which collaborative networks can actually contribute to the development of innovative policy solutions depends on how they are managed...... a Flemish administrative network to develop a radical new Spatial Planning Policy Plan. This study shows that the best way to manage collaborative innovation networks is not to press directly for results, but take the time to invest in relationship-building and together agree on a planning and clear process...

  14. Metabolic networks of longevity

    NARCIS (Netherlands)

    Houtkooper, Riekelt H.; Williams, Robert W.; Auwerx, Johan

    2010-01-01

    Molecular and cellular networks implicated in aging depend on a multitude of proteins that collectively mount adaptive and contingent metabolic responses to environmental challenges. Here, we discuss the intimate links between metabolic regulation and longevity and outline new approaches for

  15. The Human Disease Network

    National Research Council Canada - National Science Library

    Kwang-Il Goh; Michael E. Cusick; David Valle; Barton Childs; Marc Vidal; Albert-László Barabási

    2007-01-01

    A network of disorders and disease genes linked by known disordergene associations offers a platform to explore in a single graphtheoretic framework all known phenotype and disease gene associations...

  16. NIDDK Information Network (DKnet)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The NIDDK Information Network serves the needs of basic and clinical investigators by providing seamless access to large pools of data relevant to the mission of...

  17. NP Science Network Requirements

    Energy Technology Data Exchange (ETDEWEB)

    Dart, Eli [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Rotman, Lauren [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Tierney, Brian [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

    2011-08-26

    The Energy Sciences Network (ESnet) is the primary provider of network connectivity for the U.S. Department of Energy (DOE) Office of Science (SC), the single largest supporter of basic research in the physical sciences in the United States. To support SC programs, ESnet regularly updates and refreshes its understanding of the networking requirements of the instruments, facilities, scientists, and science programs it serves. This focus has helped ESnet to be a highly successful enabler of scientific discovery for over 20 years. In August 2011, ESnet and the Office of Nuclear Physics (NP), of the DOE SC, organized a workshop to characterize the networking requirements of the programs funded by NP. The requirements identified at the workshop are summarized in the Findings section, and are described in more detail in the body of the report.

  18. CRCHD Integrated Networks

    Science.gov (United States)

    INB supports the National Outreach Network, the Geographic Management of Cancer Health Disparities Program, and advises on women’s health and sexual and gender minority opportunities within and across NCI.

  19. Multitasking associative networks.

    Science.gov (United States)

    Agliari, Elena; Barra, Adriano; Galluzzi, Andrea; Guerra, Francesco; Moauro, Francesco

    2012-12-28

    We introduce a bipartite, diluted and frustrated, network as a sparse restricted Boltzmann machine and we show its thermodynamical equivalence to an associative working memory able to retrieve several patterns in parallel without falling into spurious states typical of classical neural networks. We focus on systems processing in parallel a finite (up to logarithmic growth in the volume) amount of patterns, mirroring the low-level storage of standard Amit-Gutfreund-Sompolinsky theory. Results obtained through statistical mechanics, the signal-to-noise technique, and Monte Carlo simulations are overall in perfect agreement and carry interesting biological insights. Indeed, these associative networks pave new perspectives in the understanding of multitasking features expressed by complex systems, e.g., neural and immune networks.

  20. Maintenance of family networks

    DEFF Research Database (Denmark)

    marsico, giuseppina; Chaudhary, N; Valsiner, Jaan

    2015-01-01

    collective of persons linked with one another by a flexible social network. Within such networks, Peripheral Communication Patterns set the stage for direct everyday life activities within the family context. Peripheral Communication Patterns are conditions where one family network member (A) communicates...... relatives, ancestors’ spirits, etc.) in efforts that use Peripheral Communication Patterns creates a highly redundant social context for human development over life course which is the basis for family members’ resilience during critical life events. Examples from the social contexts of Greenland, Italy......Families are social units that expand in time (across generations) and space (as a geographically distributed sub-structures of wider kinship networks). Understanding of intergenerational family relations thus requires conceptualization of communication processes that take place within a small...

  1. Learning Python network programming

    CERN Document Server

    Sarker, M O Faruque

    2015-01-01

    If you're a Python developer or a system administrator with Python experience and you're looking to take your first steps in network programming, then this book is for you. Basic knowledge of Python is assumed.

  2. Stochastic network calculus

    CERN Document Server

    Jiang, Yuming

    2009-01-01

    This book is devoted to a comprehensive treatment of this important field, a grand challenge for future networking research. It covers results from the authors as well as other researchers. Topics covered include Independent Case Analysis and its applications.

  3. The Colombia Seismological Network

    Science.gov (United States)

    Blanco Chia, J. F.; Poveda, E.; Pedraza, P.

    2013-05-01

    The latest seismological equipment and data processing instrumentation installed at the Colombia Seismological Network (RSNC) are described. System configuration, network operation, and data management are discussed. The data quality and the new seismological products are analyzed. The main purpose of the network is to monitor local seismicity with a special emphasis on seismic activity surrounding the Colombian Pacific and Caribbean oceans, for early warning in case a Tsunami is produced by an earthquake. The Colombian territory is located at the South America northwestern corner, here three tectonic plates converge: Nazca, Caribbean and the South American. The dynamics of these plates, when resulting in earthquakes, is continuously monitored by the network. In 2012, the RSNC registered in 2012 an average of 67 events per day; from this number, a mean of 36 earthquakes were possible to be located well. In 2010 the network was also able to register an average of 67 events, but it was only possible to locate a mean of 28 earthquakes daily. This difference is due to the expansion of the network. The network is made up of 84 stations equipped with different kind of broadband 40s, 120s seismometers, accelerometers and short period 1s sensors. The signal is transmitted continuously in real-time to the Central Recording Center located at Bogotá, using satellite, telemetry, and Internet. Moreover, there are some other stations which are required to collect the information in situ. Data is recorded and processed digitally using two different systems, EARTHWORM and SEISAN, which are able to process and share the information between them. The RSNC has designed and implemented a web system to share the seismological data. This innovative system uses tools like Java Script, Oracle and programming languages like PHP to allow the users to access the seismicity registered by the network almost in real time as well as to download the waveform and technical details. The coverage

  4. The Users’ Survey of Network Ethics in Taiwan Academic Network

    Directory of Open Access Journals (Sweden)

    Tao-Ming Chuang

    1998-12-01

    Full Text Available The research using the questionnaire methods is to survey the status of users in TANet and to investigate users' valuing system on network moral norms. The purposes have following: 1. analyzing and comparing different kinds of network policies, computing policies, or codes of information ethics in order to conceive the new rules on the information superhighway; 2. investigating users' background, motivation, and valuing system on network ethics; 3. analyzing network educator's attitudes on network moral norms and the methodology of ethical education in network courses; and 4. establishing the course's foundation of network ethics. [Article content in Chinese

  5. Modelling dendritic ecological networks in space: anintegrated network perspective

    Science.gov (United States)

    Peterson, Erin E.; Ver Hoef, Jay M.; Isaak, Dan J.; Falke, Jeffrey A.; Fortin, Marie-Josée; Jordon, Chris E.; McNyset, Kristina; Monestiez, Pascal; Ruesch, Aaron S.; Sengupta, Aritra; Som, Nicholas; Steel, E. Ashley; Theobald, David M.; Torgersen, Christian E.; Wenger, Seth J.

    2013-01-01

    Dendritic ecological networks (DENs) are a unique form of ecological networks that exhibit a dendritic network topology (e.g. stream and cave networks or plant architecture). DENs have a dual spatial representation; as points within the network and as points in geographical space. Consequently, some analytical methods used to quantify relationships in other types of ecological networks, or in 2-D space, may be inadequate for studying the influence of structure and connectivity on ecological processes within DENs. We propose a conceptual taxonomy of network analysis methods that account for DEN characteristics to varying degrees and provide a synthesis of the different approaches within

  6. Living Dead Networks

    Directory of Open Access Journals (Sweden)

    Eugene Thacker

    2005-01-01

    Full Text Available This essay explores, through a series of condensed modules, the ways in which contagion operates in both biological and informational networks.Through an examination of the fields of information security and medical surveillance, computer viruses and mathematical epidemiology, and pathogenic information and informed pathogens, this essay asks how the political relation between 'control' and 'emergence' is formed in networks in which the distinction between information and biology breaks down.

  7. Why Networking matters?

    Directory of Open Access Journals (Sweden)

    Romulus OPRICA

    2012-01-01

    Full Text Available The business bureaucracy, in general, makes the majority of the managers (both top and middle management neglect a key matter of success (both personal and businesslike: networking. The present paper wishes to raise a series of questions regarding Herminia Ibarra’s theory referring to the networking styles of managers on the basis of her own research on a series of managers included in the „100 top young managers” catalogue of Business Magazin.

  8. Spectrum and network measurements

    CERN Document Server

    Witte, Robert A

    2014-01-01

    This new edition of Spectrum and Network Measurements enables readers to understand the basic theory, relate it to measured results, and apply it when creating new designs. This comprehensive treatment of frequency domain measurements successfully consolidates all the pertinent theory into one text. It covers the theory and practice of spectrum and network measurements in electronic systems. It also provides thorough coverage of Fourier analysis, transmission lines, intermodulation distortion, signal-to-noise ratio and S-parameters.

  9. NETWORKS OF QUALITY IMPROVEMENT

    OpenAIRE

    Cevallos A., Juan; Universidad Nacional Mayor de San Marcos

    2014-01-01

    This article deals about the need of better highly-powered tools for quality improvement. A creative combination of Continuous Improvement Philosophy, Systems General Theory and Network General Theory is used, with the purpose of developing a Quality Improvement Network allowing an optimization of systems and processes within organizations. El artículo trata sobre la necesidad de herramientas con mayor potencia para la mejora de la calidad. Se utiliza la combinación, de manera creativa, de...

  10. Inter-organizational networks

    DEFF Research Database (Denmark)

    Bergenholtz, Carsten

    2012-01-01

    Strong and trust-based ties are usually related to homogeneous and complex knowledge, while weak ties are associated with heterogeneous and simple knowledge. Interfirm communities have been shown to depend on trust-based ties, while also relying on getting access to heterogeneous knowledge. These...... goes beyond a mere structural approach to the organization of social networks and hence proposes a tighter integration between research on social networks and organizational design....

  11. OPTIMAL NETWORK TOPOLOGY DESIGN

    Science.gov (United States)

    Yuen, J. H.

    1994-01-01

    This program was developed as part of a research study on the topology design and performance analysis for the Space Station Information System (SSIS) network. It uses an efficient algorithm to generate candidate network designs (consisting of subsets of the set of all network components) in increasing order of their total costs, and checks each design to see if it forms an acceptable network. This technique gives the true cost-optimal network, and is particularly useful when the network has many constraints and not too many components. It is intended that this new design technique consider all important performance measures explicitly and take into account the constraints due to various technical feasibilities. In the current program, technical constraints are taken care of by the user properly forming the starting set of candidate components (e.g. nonfeasible links are not included). As subsets are generated, they are tested to see if they form an acceptable network by checking that all requirements are satisfied. Thus the first acceptable subset encountered gives the cost-optimal topology satisfying all given constraints. The user must sort the set of "feasible" link elements in increasing order of their costs. The program prompts the user for the following information for each link: 1) cost, 2) connectivity (number of stations connected by the link), and 3) the stations connected by that link. Unless instructed to stop, the program generates all possible acceptable networks in increasing order of their total costs. The program is written only to generate topologies that are simply connected. Tests on reliability, delay, and other performance measures are discussed in the documentation, but have not been incorporated into the program. This program is written in PASCAL for interactive execution and has been implemented on an IBM PC series computer operating under PC DOS. The disk contains source code only. This program was developed in 1985.

  12. Artificial neural network modelling

    CERN Document Server

    Samarasinghe, Sandhya

    2016-01-01

    This book covers theoretical aspects as well as recent innovative applications of Artificial Neural networks (ANNs) in natural, environmental, biological, social, industrial and automated systems. It presents recent results of ANNs in modelling small, large and complex systems under three categories, namely, 1) Networks, Structure Optimisation, Robustness and Stochasticity 2) Advances in Modelling Biological and Environmental Systems and 3) Advances in Modelling Social and Economic Systems. The book aims at serving undergraduates, postgraduates and researchers in ANN computational modelling. .

  13. Wireless Computational Networking Architectures

    Science.gov (United States)

    2013-12-01

    2] T. Ho, M. Medard, R. Kotter , D. Karger, M. Effros, J. Shi, and B. Leong, “A Random Linear Network Coding Approach to Multicast,” IEEE...218, January 2008. [10] R. Kotter and F. R. Kschischang, “Coding for Errors and Erasures in Random Network Coding,” IEEE Transactions on...Systems, Johns Hopkins University, Baltimore, Maryland, 2011. 6. B. W. Suter and Z. Yan U.S. Patent Pending 13/949,319 Rank Deficient Decoding

  14. Avi Sorting Network

    OpenAIRE

    Avinash Bansal; Kamal Gupta

    2012-01-01

    Sorting network is an abstract mathematical modelwhich can be used as a multiple-input, multiple-output switchingnetwork to sort the data in ascending or descending order [1].Sorting has been one of the most critical applications on parallelcomputing machines. Many classic textbooks on algorithms likeThomas H. Cormen, therefore consider this problem in greatdetail and list many sorting network for this purpose [2]. Thereare many sorting algorithms as the Bubble / Insertion sorter,Odd-Even sor...

  15. Bayesian Networks An Introduction

    CERN Document Server

    Koski, Timo

    2009-01-01

    Bayesian Networks: An Introduction provides a self-contained introduction to the theory and applications of Bayesian networks, a topic of interest and importance for statisticians, computer scientists and those involved in modelling complex data sets. The material has been extensively tested in classroom teaching and assumes a basic knowledge of probability, statistics and mathematics. All notions are carefully explained and feature exercises throughout. Features include:.: An introduction to Dirichlet Distribution, Exponential Families and their applications.; A detailed description of learni

  16. Network Security Visualization

    Science.gov (United States)

    1999-09-27

    Internet Scanner 5.2 User Guide for Windows NT”, Internet Security Systems, Inc., 1998. “SBIR Topic AF97-043 Network Security Visualization...to the Server application to import into the NSV system database data that gets queried from ISS Internet Security Scanner 5.4. Objective #5 was... Internet Security Scanner scan of a live network and imported through a Cartridge component. The data was accessed through the Server component and

  17. Network Formation and Cooperation

    OpenAIRE

    Felipe Balmaceda

    2004-01-01

    In this paper we adopt Granovetter's view expressed in his famous article ''Economic Action and Social Structure: The Problem of Embeddedness'' , where he argues that the concept of man in economics is extremely undersocialized because it ignores the importance of social networks. In so doing the incentives to mutual cooperation in social matching games in which the social network is endogenously determined are studied. The main result shows that in atomized societies where there is no inform...

  18. Revisiting Friendship Networks

    OpenAIRE

    Aditi Roy; Sudipta Sarangi

    2009-01-01

    We extend the model of friendship networks developed by Brueck- ner (2006) in two ways. First, we extend the level of indirect benefits by incorporating benefits from up to three links and explore its impli- cation for the socially optimal and individual e¤ort levels. Next, we generalize the magnetic agent problem by allowing for more than 3 players by restricting ourselves to regular networks that include pay- o¤s from the magnetic agent.

  19. Fixed Access Network Sharing

    Science.gov (United States)

    Cornaglia, Bruno; Young, Gavin; Marchetta, Antonio

    2015-12-01

    Fixed broadband network deployments are moving inexorably to the use of Next Generation Access (NGA) technologies and architectures. These NGA deployments involve building fiber infrastructure increasingly closer to the customer in order to increase the proportion of fiber on the customer's access connection (Fibre-To-The-Home/Building/Door/Cabinet… i.e. FTTx). This increases the speed of services that can be sold and will be increasingly required to meet the demands of new generations of video services as we evolve from HDTV to "Ultra-HD TV" with 4k and 8k lines of video resolution. However, building fiber access networks is a costly endeavor. It requires significant capital in order to cover any significant geographic coverage. Hence many companies are forming partnerships and joint-ventures in order to share the NGA network construction costs. One form of such a partnership involves two companies agreeing to each build to cover a certain geographic area and then "cross-selling" NGA products to each other in order to access customers within their partner's footprint (NGA coverage area). This is tantamount to a bi-lateral wholesale partnership. The concept of Fixed Access Network Sharing (FANS) is to address the possibility of sharing infrastructure with a high degree of flexibility for all network operators involved. By providing greater configuration control over the NGA network infrastructure, the service provider has a greater ability to define the network and hence to define their product capabilities at the active layer. This gives the service provider partners greater product development autonomy plus the ability to differentiate from each other at the active network layer.

  20. Why Networking matters?

    OpenAIRE

    Romulus OPRICA

    2012-01-01

    The business bureaucracy, in general, makes the majority of the managers (both top and middle management) neglect a key matter of success (both personal and businesslike): networking. The present paper wishes to raise a series of questions regarding Herminia Ibarra’s theory referring to the networking styles of managers on the basis of her own research on a series of managers included in the „100 top young managers” catalogue of Business Magazin.