871 resultados para Decoupling and matching networks


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The human brainstem is a densely packed, complex but highly organised structure. It not only serves as a conduit for long projecting axons conveying motor and sensory information, but also is the location of multiple primary nuclei that control or modulate a vast array of functions, including homeostasis, consciousness, locomotion, and reflexive and emotive behaviours. Despite its importance, both in understanding normal brain function as well as neurodegenerative processes, it remains a sparsely studied structure in the neuroimaging literature. In part, this is due to the difficulties in imaging the internal architecture of the brainstem in vivo in a reliable and repeatable fashion. A modified multivariate mixture of Gaussians (mmMoG) was applied to the problem of multichannel tissue segmentation. By using quantitative magnetisation transfer and proton density maps acquired at 3 T with 0.8 mm isotropic resolution, tissue probability maps for four distinct tissue classes within the human brainstem were created. These were compared against an ex vivo fixated human brain, imaged at 0.5 mm, with excellent anatomical correspondence. These probability maps were used within SPM8 to create accurate individual subject segmentations, which were then used for further quantitative analysis. As an example, brainstem asymmetries were assessed across 34 right-handed individuals using voxel based morphometry (VBM) and tensor based morphometry (TBM), demonstrating highly significant differences within localised regions that corresponded to motor and vocalisation networks. This method may have important implications for future research into MRI biomarkers of pre-clinical neurodegenerative diseases such as Parkinson's disease.

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Sleep-wake cycle is characterized by changes in neuronal network activity. However, for the last decade there is increasing evidence that neuroglial interaction may play a role in the modulation of sleep homeostasis and that astrocytes have a critical impact in this process. Interestingly, astrocytes are organized into communicating networks based on their high expression of connexins, which are the molecular constituents of gap junction channels. Thus, neuroglial interactions should also be considered as the result of the interplay between neuronal and astroglial networks. Here, we investigate the effect of modafinil, a wakefulness-promoting agent, on astrocyte gap junctional communication. We report that in the cortex modafinil injection increases the expression of mRNA and protein of connexin 30 but not those of connexin 43, the other major astroglial connexin. These increases are correlated with an enhancement of intercellular dye coupling in cortical astrocytes, which is abolished when neuronal activity is silenced by tetrodotoxin. Moreover, gamma-hydroxybutyric acid, which at a millimolar concentration induces sleep, has an opposite effect on astroglial gap junctions in an activity-independent manner. These results support the proposition that astroglia may play an important role in complex physiological brain functions, such as sleep regulation, and that neuroglial networking interaction is modified during sleep-wake cycle. This article is part of the Special Issue Section entitled 'Current Pharmacology of Gap Junction Channels and Hemichannels'.

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The motivation for this research initiated from the abrupt rise and fall of minicomputers which were initially used both for industrial automation and business applications due to their significantly lower cost than their predecessors, the mainframes. Later industrial automation developed its own vertically integrated hardware and software to address the application needs of uninterrupted operations, real-time control and resilience to harsh environmental conditions. This has led to the creation of an independent industry, namely industrial automation used in PLC, DCS, SCADA and robot control systems. This industry employs today over 200'000 people in a profitable slow clockspeed context in contrast to the two mainstream computing industries of information technology (IT) focused on business applications and telecommunications focused on communications networks and hand-held devices. Already in 1990s it was foreseen that IT and communication would merge into one Information and communication industry (ICT). The fundamental question of the thesis is: Could industrial automation leverage a common technology platform with the newly formed ICT industry? Computer systems dominated by complex instruction set computers (CISC) were challenged during 1990s with higher performance reduced instruction set computers (RISC). RISC started to evolve parallel to the constant advancement of Moore's law. These developments created the high performance and low energy consumption System-on-Chip architecture (SoC). Unlike to the CISC processors RISC processor architecture is a separate industry from the RISC chip manufacturing industry. It also has several hardware independent software platforms consisting of integrated operating system, development environment, user interface and application market which enables customers to have more choices due to hardware independent real time capable software applications. An architecture disruption merged and the smartphone and tablet market were formed with new rules and new key players in the ICT industry. Today there are more RISC computer systems running Linux (or other Unix variants) than any other computer system. The astonishing rise of SoC based technologies and related software platforms in smartphones created in unit terms the largest installed base ever seen in the history of computers and is now being further extended by tablets. An underlying additional element of this transition is the increasing role of open source technologies both in software and hardware. This has driven the microprocessor based personal computer industry with few dominating closed operating system platforms into a steep decline. A significant factor in this process has been the separation of processor architecture and processor chip production and operating systems and application development platforms merger into integrated software platforms with proprietary application markets. Furthermore the pay-by-click marketing has changed the way applications development is compensated: Three essays on major trends in a slow clockspeed industry: The case of industrial automation 2014 freeware, ad based or licensed - all at a lower price and used by a wider customer base than ever before. Moreover, the concept of software maintenance contract is very remote in the app world. However, as a slow clockspeed industry, industrial automation has remained intact during the disruptions based on SoC and related software platforms in the ICT industries. Industrial automation incumbents continue to supply systems based on vertically integrated systems consisting of proprietary software and proprietary mainly microprocessor based hardware. They enjoy admirable profitability levels on a very narrow customer base due to strong technology-enabled customer lock-in and customers' high risk leverage as their production is dependent on fault-free operation of the industrial automation systems. When will this balance of power be disrupted? The thesis suggests how industrial automation could join the mainstream ICT industry and create an information, communication and automation (ICAT) industry. Lately the Internet of Things (loT) and weightless networks, a new standard leveraging frequency channels earlier occupied by TV broadcasting, have gradually started to change the rigid world of Machine to Machine (M2M) interaction. It is foreseeable that enough momentum will be created that the industrial automation market will in due course face an architecture disruption empowered by these new trends. This thesis examines the current state of industrial automation subject to the competition between the incumbents firstly through a research on cost competitiveness efforts in captive outsourcing of engineering, research and development and secondly researching process re- engineering in the case of complex system global software support. Thirdly we investigate the industry actors', namely customers, incumbents and newcomers, views on the future direction of industrial automation and conclude with our assessments of the possible routes industrial automation could advance taking into account the looming rise of the Internet of Things (loT) and weightless networks. Industrial automation is an industry dominated by a handful of global players each of them focusing on maintaining their own proprietary solutions. The rise of de facto standards like IBM PC, Unix and Linux and SoC leveraged by IBM, Compaq, Dell, HP, ARM, Apple, Google, Samsung and others have created new markets of personal computers, smartphone and tablets and will eventually also impact industrial automation through game changing commoditization and related control point and business model changes. This trend will inevitably continue, but the transition to a commoditized industrial automation will not happen in the near future.

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Drinking habits are socially patterned and social networks influence individuals' drinking behaviors. Previous studies have focused primarily upon the influence from family members to drink less. Those studies that have focused upon peer influence have been largely confined to social norms among adolescent and college-age drinkers. By contrast, based in adult populations, this article examines exhortations from friends not only to reduce alcohol consumption but also to increase it. Survey data in 15 countries that participate in the Gender, Alcohol and Culture: An International Study project (GENACIS) were used to test whether there were country and gender differences concerning the influence to drink less or to drink more by friends and examine if this was affected by the drinking behavior. The findings revealed that those influenced to drink less had more heavy episodic drinking (HED) occasions than those who did not report such influence. By contrast, influence to drink more, originating mainly from same-sex friends, may be more the result of social situations that encourage all drinkers, regardless of their frequency of HED occasions. At the country level, influence to drink less for both sexes decreased with the proportion of drinkers in a country. Similarly, influence to drink less for both sexes also decreased in countries where gender roles were more egalitarian. Thus, in countries where alcohol use is more widespread and fewer differences are observed between male and female gender role expectations, fewer people were influenced to drink less. These findings have implications for social and behavioral strategies designed to reduce alcohol-related harm across a wide range of cultures.

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Artifacts are present in most of the electroencephalography (EEG) recordings, making it difficult to interpret or analyze the data. In this paper a cleaning procedure based on a multivariate extension of empirical mode decomposition is used to improve the quality of the data. This is achieved by applying the cleaning method to raw EEG data. Then, a synchrony measure is applied on the raw and the clean data in order to compare the improvement of the classification rate. Two classifiers are used, linear discriminant analysis and neural networks. For both cases, the classification rate is improved about 20%.

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Les protestes socials esdevingudes en nombrosos països durant els últims tres anys –des de Tunísia i l’anomenada “Primavera àrab” fins a les recents mobilitzacions a Turquia o Brasil– han fet aflorar un debat sobre la possible dimensió global i transestatal de totes elles. El present article pretén realitzar una aproximació descriptiva i analítica a aquest intens cicle de protestes, reflexionant sobre les diferències i similituds existents entre elles, el paper que Internet i les xarxes socials han tingut en el curs de les diferents mobilitzacions o, entre altres aspectes, el repertori d’accions que han emprat. Més enllà d’aquests trets compartits o no, l’article mira d’emfasitzar la importància d’entendre aquest cicle de mobilitzacions com un procés de repolitització social que combina les contradiccions i conflictes locals de cada context en particular amb l’aparent existència d’una demanda global per major democratització política, regeneració institucional, justícia social i reapropiació d’allò comú.

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Metabolic homeostasis is achieved by complex molecular and cellular networks that differ significantly among individuals and are difficult to model with genetically engineered lines of mice optimized to study single gene function. Here, we systematically acquired metabolic phenotypes by using the EUMODIC EMPReSS protocols across a large panel of isogenic but diverse strains of mice (BXD type) to study the genetic control of metabolism. We generated and analyzed 140 classical phenotypes and deposited these in an open-access web service for systems genetics (www.genenetwork.org). Heritability, influence of sex, and genetic modifiers of traits were examined singly and jointly by using quantitative-trait locus (QTL) and expression QTL-mapping methods. Traits and networks were linked to loci encompassing both known variants and novel candidate genes, including alkaline phosphatase (ALPL), here linked to hypophosphatasia. The assembled and curated phenotypes provide key resources and exemplars that can be used to dissect complex metabolic traits and disorders.

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Key Points: • Iowa’s exceptional agricultural productivity is dependent upon nutrient‐rich soils with high carbon and nitrogen stocks. • Soil carbon and nitrogen stocks in Iowa corn‐soybean rotations are at significant risk of long‐term decline. • Soil carbon and nitrogen stocks are a function of crop residue inputs. • Nutrient input levels that do not maximize crop yield and residue production are likely to reduce soil carbon and nitrogen stocks. • If soil carbon and nitrogen stocks decline, water quality improvements become more difficult. • Soil carbon and nitrogen balances are extremely difficult to measure, but positive balances are essential to the future of Iowa agriculture. Recommended Actions: • Accurate measurement of soil carbon and nitrogen balances is exceptionally difficult, but can be accomplished with sufficient investment and long‐term planning. • The ideal approach will include a combination of measurements from farms and experimental networks that manipulate nutrient inputs. • With proper planning and cooperation, Iowa State University and the Iowa Department of Agriculture and Land Stewardship can address the concerns raised in this report regarding the future of Iowa’s soil resource and agricultural productivity.

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The present paper advocates for the creation of a federated, hybrid database in the cloud, integrating law data from all available public sources in one single open access system - adding, in the process, relevant meta-data to the indexed documents, including the identification of social and semantic entities and the relationships between them, using linked open data techniques and standards such as RDF. Examples of potential benefits and applications of this approach are also provided, including, among others, experiences from of our previous research, in which data integration, graph databases and social and semantic networks analysis were used to identify power relations, litigation dynamics and cross-references patterns both intra and inter-institutionally, covering most of the World international economic courts.

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Suomen Viestintävirasto Ficora on antanut määräyksen 13/2005M, jonka mukaan internet-palveluntarjoajalla tulee olla ennalta määritellyt prosessit ja toimintamallit sen omista asiakasliittymistä internetiin lähtevän haitallisen liikenteen havaitsemiseksi ja suodattamiseksi. Määräys ei sinällään aseta ehtoja, kuinka asetetut vaatimukset kukin internet-palveluntarjoaja täyttää. Tässä diplomityössä annetaan määritelmät haitalliselle liikenteelle ja tutkitaan menetelmiä, joilla sitä voidaan havainnoida ja suodattaa paikallisen internet-palveluntarjoajan operaattoriverkoissa. Suhteutettunapaikallisen internet-palveluntarjoajan asiakasliittymien määrään, uhkien vakavuuteen ja tällaisen systeemin kustannuksiin, tullaan tämän työn pohjalta ehdottamaan avoimen lähdekoodin tunkeutumisenhavaitsemistyökalua nopeaa reagointia vaativiin tietoturvaloukkauksiin ja automatisoitua uudelleenreitititystä suodatukseen. Lisäksi normaalin työajan puitteissa tapahtuvaan liikenteen seurantaan suositetaan laajennettua valvontapöytää, jossa tarkemmat tutkimukset voidaan laittaa alulle visualisoitujen reaaliaikaisten tietoliikenneverkon tietovoiden kautta.

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Työn tavoitteena on selvittää kuinka yritykset osallistuvat työvoimakoulutuksen suunnitteluun. Kyselyn avulla on selvitetty suunnitteluprosessia, johon osallistui osa TE-keskuksista ja työvoimatoimistoista. Kirjallisuustutkimuksessa tarkastellaan osaamisintensiivisiä liike-elämän palveluita, tiedon hallintaa, miljöön analysointia, liiketoimintasuhteita sekä verkostoitumista. Tutkimuksen empiirisessä osassa tarkastellaan työhallinnon tavoitteita ja kyselyn avulla selvitettyjätoimintatapoja yritysten osallistumisesta työvoimakoulutuksen suunnitteluun. Tuloksena saatiin runsaasti yhteistyötapoja yritysten kanssa, mutta Lappeenrannan työvoimatoimiston näkökulmasta ei mitään uutta noussut esille. Suoran yhteistyön esteenä on edelleen yrityksien sekä myös työvoimahallinnon motivaationpuute.

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Tämän työn tavoitteena on tutkia born global -yhtiön resursseja ¿ erityisesti perustajan näkökulmasta - ja kuinka he ovat selviytyneet rajoitettujen resurssien ongelmasta yritystä perustettaessa. Born global - yritykset ovat nuoria, tietointensiivisiä ja nopeasti kansainvälistyviä pieniä ja keskisuuria yrityksiä. Niiden resurssit ovat usein vajavaisia ja ristiriidassa niiden maailmanlaajuisen vision kanssa. Myös born global - yrityksen piirteet ja strategia asettavat paineita yhtiön resursseille. Tämän tutkimuksen empirinen osa perustuu tapaustutkimukselle, jossa analysoidaan kahden born global -tapauksen resursseja ja yrittäjiä. Born global -tutkijat ovat pyrkineet löytämään syytä viime aikaiselle born global -yrityksien lisääntymiselle ja hahmottamaan born global -yrityksen resursseja ja born global -yrittäjien ominaisuuksia. Tutkimuksesta käy ilmi, että born global -ilmiön kasvanutta määrää ei voida selittää yhdellä tai kahdella muuttujalla. Mutta kuitenkin eräitä kriittisiä tekijöitä löytyi case-organisaatioista, jotka ovat laskeneet rimaa perustaa born global -yritys. Erityisesti ulkomaankokemus, kielitaito ja käytännölliset verkostot nähtiin tärkeiksi molemmissacase-organisaatioissa. Kävi myös ilmi, että molemmat perustaja-yrittäjät olivat vahvasti motivoituneita. Kuitenkin motivaation lähde vaihteli perustajien kesken ollen kuitenkin vahvasti yhteydessä omaan persoonaan. Mitään kattavampaa johtopäätöstä ei kyetty tekemään, joten jatkotutkimus tämän alueenosalta on tarvittavaa. Tulokset näyttävät siltä, että born global -yrityksen perustajat omaavat tärkeän roolin yhtiön suorituskykyyn liittyen. Erityisesti erintyyppisten verkostojen rooli nähtiin elintärkeänä born global-yrityksen menestykselle ¿ verkostot nähtiin keinona haalia kriittisiä resursseja. Tulokset tukevat teoriaa born global -yrityksen resursseista.

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Tutkimuksen tarkoitus on tuottaa ajantasaista tietoutta siitä, millainen käsitys laskenta-alan tradenomi- ja maisteriopiskelijoilla on tämän päivän tilitoimistotyöstä ja koetaanko tilitoimisto kiinnostavana työpaikkana. Asiaa tarkasteltiin tietotyön monipuolisuuden ja motivaation näkökulmasta. Tutkimuksen empiirinen osuus toteutettiin nettikyselynä, joka kohdistettiin viimeisen vuoden taloushallinnon tai laskentatoimen pääainetta Suomessa opiskeleville tradenomi- ja maisteriopiskelijoille. Vastauksia saatiin 182, joista 162 oli tradenomi- ja 20 kauppatieteiden maisteriopiskelijoilta. Tutkimus toteutettiin kvantitatiivisena. Vastaajista 55 prosenttia pititilitoimistoa kiinnostavana ja 25 prosenttia melko kiinnostavana työpaikkana. Tulokset osoittavat, että tilitoimistotyö on kiinnostava vaihtoehto henkilöille, jotka kokevat työn itseään sisäisesti motivoivaksi. Sisäistä motivaatiota voidaan parantaa ulkoiseen motivaatioon vaikuttavia, kuten rahallisia ja sosiaalisia palkkioita, lisäämällä. Myös asiakaslähtöiset työtehtävät ja verkostomainen toimintatapa vaikuttavat sisäiseen motivaatioon. Työntekijän vaikutusmahdollisuudet omaan työhönsä lisäävät puolestaan ulkoista motivaatiota. Tieto- ja viestintätekniikan monipuolinen hyödyntäminen selittää ulkoisesta motivaatiosta pienen osan. Tietotyön ulottuvuuksista ainoastaan koulutus- ja kehittämismahdollisuudet eivätvaikuta motivaatioon eivätkä tilitoimiston kiinnostavuuteen työpaikkana. Tulokset osoittavat tilitoimistotyön olevan tulevien tietotyöntekijöiden näkemyksen mukaan monipuolista tietotyötä. Tilitoimistotyössä hyödynnetääntieto- ja viestintätekniikkaa monipuolisesti, ja se sisältää omaa suunnittelua vaativia työtehtäviä. Työ vaatii tekijältään korkeaa ja laaja-alaista osaamista sekä jatkuvaa itsensä kehittämistä. Tilitoimistot toimivat sekä sisäisissä että ulkoisissa verkostoissa, joten työntekijät tarvitsevat myös sosiaalisia taitoja.Tilitoimistot tarjoavat työntekijöille melko hyvät vaikutusmahdollisuudet omaantyöhönsä. Tilitoimistotyön arvioitiin tarjoavan muuta tietotyötä paremmat koulutus- ja itsensä kehittämismahdollisuudet. Huolimatta monipuolisuudesta tietotyönnäkökulmasta, tilitoimistotyötä pidettiin yleensä liian säännöllisenä rutiinityönä.

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Increasing evidence suggests that working memory and perceptual processes are dynamically interrelated due to modulating activity in overlapping brain networks. However, the direct influence of working memory on the spatio-temporal brain dynamics of behaviorally relevant intervening information remains unclear. To investigate this issue, subjects performed a visual proximity grid perception task under three different visual-spatial working memory (VSWM) load conditions. VSWM load was manipulated by asking subjects to memorize the spatial locations of 6 or 3 disks. The grid was always presented between the encoding and recognition of the disk pattern. As a baseline condition, grid stimuli were presented without a VSWM context. VSWM load altered both perceptual performance and neural networks active during intervening grid encoding. Participants performed faster and more accurately on a challenging perceptual task under high VSWM load as compared to the low load and the baseline condition. Visual evoked potential (VEP) analyses identified changes in the configuration of the underlying sources in one particular period occurring 160-190 ms post-stimulus onset. Source analyses further showed an occipito-parietal down-regulation concurrent to the increased involvement of temporal and frontal resources in the high VSWM context. Together, these data suggest that cognitive control mechanisms supporting working memory may selectively enhance concurrent visual processing related to an independent goal. More broadly, our findings are in line with theoretical models implicating the engagement of frontal regions in synchronizing and optimizing mnemonic and perceptual resources towards multiple goals.