926 resultados para BASIS FUNCTION NETWORK
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Abstract Background: Many complex systems can be represented and analysed as networks. The recent availability of large-scale datasets, has made it possible to elucidate some of the organisational principles and rules that govern their function, robustness and evolution. However, one of the main limitations in using protein-protein interactions for function prediction is the availability of interaction data, especially for Mollicutes. If we could harness predicted interactions, such as those from a Protein-Protein Association Networks (PPAN), combining several protein-protein network function-inference methods with semantic similarity calculations, the use of protein-protein interactions for functional inference in this species would become more potentially useful. Results: In this work we show that using PPAN data combined with other approximations, such as functional module detection, orthology exploitation methods and Gene Ontology (GO)-based information measures helps to predict protein function in Mycoplasma genitalium. Conclusions: To our knowledge, the proposed method is the first that combines functional module detection among species, exploiting an orthology procedure and using information theory-based GO semantic similarity in PPAN of the Mycoplasma species. The results of an evaluation show a higher recall than previously reported methods that focused on only one organism network.
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Assessing the contribution of promoters and coding sequences to gene evolution is an important step toward discovering the major genetic determinants of human evolution. Many specific examples have revealed the evolutionary importance of cis-regulatory regions. However, the relative contribution of regulatory and coding regions to the evolutionary process and whether systemic factors differentially influence their evolution remains unclear. To address these questions, we carried out an analysis at the genome scale to identify signatures of positive selection in human proximal promoters. Next, we examined whether genes with positively selected promoters (Prom+ genes) show systemic differences with respect to a set of genes with positively selected protein-coding regions (Cod+ genes). We found that the number of genes in each set was not significantly different (8.1% and 8.5%, respectively). Furthermore, a functional analysis showed that, in both cases, positive selection affects almost all biological processes and only a few genes of each group are located in enriched categories, indicating that promoters and coding regions are not evolutionarily specialized with respect to gene function. On the other hand, we show that the topology of the human protein network has a different influence on the molecular evolution of proximal promoters and coding regions. Notably, Prom+ genes have an unexpectedly high centrality when compared with a reference distribution (P = 0.008, for Eigenvalue centrality). Moreover, the frequency of Prom+ genes increases from the periphery to the center of the protein network (P = 0.02, for the logistic regression coefficient). This means that gene centrality does not constrain the evolution of proximal promoters, unlike the case with coding regions, and further indicates that the evolution of proximal promoters is more efficient in the center of the protein network than in the periphery. These results show that proximal promoters have had a systemic contribution to human evolution by increasing the participation of central genes in the evolutionary process.
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In the administration, planning, design, and maintenance of road systems, transportation professionals often need to choose between alternatives, justify decisions, evaluate tradeoffs, determine how much to spend, set priorities, assess how well the network meets traveler needs, and communicate the basis for their actions to others. A variety of technical guidelines, tools, and methods have been developed to help with these activities. Such work aids include design criteria guidelines, design exception analysis methods, needs studies, revenue allocation schemes, regional planning guides, designation of minimum standards, sufficiency ratings, management systems, point based systems to determine eligibility for paving, functional classification, and bridge ratings. While such tools play valuable roles, they also manifest a number of deficiencies and are poorly integrated. Design guides tell what solutions MAY be used, they aren't oriented towards helping find which one SHOULD be used. Design exception methods help justify deviation from design guide requirements but omit consideration of important factors. Resource distribution is too often based on dividing up what's available rather than helping determine how much should be spent. Point systems serve well as procedural tools but are employed primarily to justify decisions that have already been made. In addition, the tools aren't very scalable: a system level method of analysis seldom works at the project level and vice versa. In conjunction with the issues cited above, the operation and financing of the road and highway system is often the subject of criticisms that raise fundamental questions: What is the best way to determine how much money should be spent on a city or a county's road network? Is the size and quality of the rural road system appropriate? Is too much or too little money spent on road work? What parts of the system should be upgraded and in what sequence? Do truckers receive a hidden subsidy from other motorists? Do transportation professions evaluate road situations from too narrow of a perspective? In considering the issues and questions the author concluded that it would be of value if one could identify and develop a new method that would overcome the shortcomings of existing methods, be scalable, be capable of being understood by the general public, and utilize a broad viewpoint. After trying out a number of concepts, it appeared that a good approach would be to view the road network as a sub-component of a much larger system that also includes vehicles, people, goods-in-transit, and all the ancillary items needed to make the system function. Highway investment decisions could then be made on the basis of how they affect the total cost of operating the total system. A concept, named the "Total Cost of Transportation" method, was then developed and tested. The concept rests on four key principles: 1) that roads are but one sub-system of a much larger 'Road Based Transportation System', 2) that the size and activity level of the overall system are determined by market forces, 3) that the sum of everything expended, consumed, given up, or permanently reserved in building the system and generating the activity that results from the market forces represents the total cost of transportation, and 4) that the economic purpose of making road improvements is to minimize that total cost. To test the practical value of the theory, a special database and spreadsheet model of Iowa's county road network was developed. This involved creating a physical model to represent the size, characteristics, activity levels, and the rates at which the activities take place, developing a companion economic cost model, then using the two in tandem to explore a variety of issues. Ultimately, the theory and model proved capable of being used in full system, partial system, single segment, project, and general design guide levels of analysis. The method appeared to be capable of remedying many of the existing work method defects and to answer society's transportation questions from a new perspective.
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The Iowa Department of Education (DE) was appropriated $1.45 million for the development and implementation of a statewide work-based learning intermediary network. This funding was awarded on a competitive basis to 15 regional intermediary networks. Funds received by the regional intermediary networks from the state through this grant are to be used to develop and expand work-based learning opportunities within each region. A match of resources equal to 25 percent was a requirement of the funding. This match could include private donations, in-kind contributions, or public moneys. Funds may be used to support personnel responsible for the implementation of the intermediary network program components.
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Neuronal networks in vitro are prominent systems to study the development of connections in living neuronal networks and the interplay between connectivity, activity and function. These cultured networks show a rich spontaneous activity that evolves concurrently with the connectivity of the underlying network. In this work we monitor the development of neuronal cultures, and record their activity using calcium fluorescence imaging. We use spectral analysis to characterize global dynamical and structural traits of the neuronal cultures. We first observe that the power spectrum can be used as a signature of the state of the network, for instance when inhibition is active or silent, as well as a measure of the network's connectivity strength. Second, the power spectrum identifies prominent developmental changes in the network such as GABAA switch. And third, the analysis of the spatial distribution of the spectral density, in experiments with a controlled disintegration of the network through CNQX, an AMPA-glutamate receptor antagonist in excitatory neurons, reveals the existence of communities of strongly connected, highly active neurons that display synchronous oscillations. Our work illustrates the interest of spectral analysis for the study of in vitro networks, and its potential use as a network-state indicator, for instance to compare healthy and diseased neuronal networks.
Abnormalities of sodium excretion and other disorders of renal function in fulminant hepatic failure
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Renal function was evaluated in 40 patients with fulminant hepatic failure, They were divided into two groups on the basis of glomerular filtration rates greater than 40 ml/min or less than 25 ml/min. A number of patients in group 1 had markedly abnormal renal retention of sodium together with a reduced free water clearance and low potassium excretion which could be explained by increased proximal tubular reabsorption of sodium. The patients in group 2 had evidence that renal tubular integrity was maintained when the glomerular filtration rate was greater than or equal ml/min (functional renal failure), but evidence of tubular damage was present when this was less than 3 ml/min (acute tubular necrosis).
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Here we report that the kinesin-5 motor Klp61F, which is known for its role in bipolar spindle formation in mitosis, is required for protein transport from the Golgi complex to the cell surface in Drosophila S2 cells. Disrupting the function of its mammalian orthologue, Eg5, in HeLa cells inhibited secretion of a protein called pancreatic adenocarcinoma up-regulated factor (PAUF) but, surprisingly, not the trafficking of vesicular stomatitis virus G protein (VSV-G) to the cell surface. We have previously reported that PAUF is transported from the trans-Golgi network (TGN) to the cell surface in specific carriers called CARTS that exclude VSV-G. Inhibition of Eg5 function did not affect the biogenesis of CARTS; however, their migration was delayed and they accumulated near the Golgi complex. Altogether, our findings reveal a surprising new role of Eg5 in nonmitotic cells in the facilitation of the transport of specific carriers, CARTS, from the TGN to the cell surface.
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Cortical electrical stimulation mapping was used to study neural substrates of the function of writing in the temporoparietal cortex. We identified the sites involved in oral language (sentence reading and naming) and writing from dictation, in order to spare these areas during removal of brain tumours in 30 patients (23 in the left, and 7 in the right hemisphere). Electrostimulation of the cortex impaired writing ability in 62 restricted cortical areas (.25 cm2). These were found in left temporoparietal lobes and were mostly located along the superior temporal gyrus (Brodmann's areas 22 and 42). Stimulation of right temporoparietal lobes in right-handed patients produced no writing impairments. However there was a high variability of location between individuals. Stimulation resulted in combined symptoms (affecting oral language and writing) in fourteen patients, whereas in eight other patients, stimulation-induced pure agraphia symptoms with no oral language disturbance in twelve of the identified areas. Each detected area affected writing in a different way. We detected the various different stages of the auditory-to-motor pathway of writing from dictation: either through comprehension of the dictated sentences (word deafness areas), lexico-semantic retrieval, or phonologic processing. In group analysis, barycentres of all different types of writing interferences reveal a hierarchical functional organization along the superior temporal gyrus from initial word recognition to lexico-semantic and phonologic processes along the ventral and the dorsal comprehension pathways, supporting the previously described auditory-to-motor process. The left posterior Sylvian region supports different aspects of writing function that are extremely specialized and localized, sometimes being segregated in a way that could account for the occurrence of pure agraphia that has long-been described in cases of damage to this region.
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Music is a highly complex and versatile stimulus for the brain that engages many temporal, frontal, parietal, cerebellar, and subcortical areas involved in auditory, cognitive, emotional, and motor processing. Regular musical activities have been shown to effectively enhance the structure and function of many brain areas, making music a potential tool also in neurological rehabilitation. In our previous randomized controlled study, we found that listening to music on a daily basis can improve cognitive recovery and improve mood after an acute middle cerebral artery stroke. Extending this study, a voxel-based morphometry (VBM) analysis utilizing cost function masking was performed on the acute and 6-month post-stroke stage structural magnetic resonance imaging data of the patients (n = 49) who either listened to their favorite music [music group (MG), n = 16] or verbal material [audio book group (ABG), n = 18] or did not receive any listening material [control group (CG), n = 15] during the 6-month recovery period. Although all groups showed significant gray matter volume (GMV) increases from the acute to the 6-month stage, there was a specific network of frontal areas [left and right superior frontal gyrus (SFG), right medial SFG] and limbic areas [left ventral/subgenual anterior cingulate cortex (SACC) and right ventral striatum (VS)] in patients with left hemisphere damage in which the GMV increases were larger in the MG than in the ABG and in the CG. Moreover, the GM reorganization in the frontal areas correlated with enhanced recovery of verbal memory, focused attention, and language skills, whereas the GM reorganization in the SACC correlated with reduced negative mood. This study adds on previous results, showing that music listening after stroke not only enhances behavioral recovery, but also induces fine-grained neuroanatomical changes in the recovering brain.
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Tässä työssä käsitellään niitä motiiveja, haasteita ja menestystekijöitä, jotka vaikuttavat lisäarvoatuottavassa liiketoimintaverkostossa. Työssä on selvitetty sitä, miten partneriverkostot syntyvät sekä mitkä seikat vaikuttavat siihen jatkuuko yhteistyö vai ei. Motiiveja partneruuteen on tutkittu kirjallisuudesta sekä analysoimalla työssä esitettyä tapausta. Tässä työssä käydään keskustelua myös partneruuden elinkaaresta, jota ei ole käsitellyssä kirjallisuudessa tuotu esille. Työssä esitettyä tapausta arvioitiin lähettämällä siihen liittyneille henkilöille kysely. Kyselyiden lähettämisen jälkeen järjestettiin haastattelu kyselyyn vastanneiden kanssa. Lopputulokset perustuvat pitkälti haastateltujen henkilöiden kanssa käytyihin keskusteluihin. Kävi ilmi, että arvoa tuottavan partneriverkoston yksi tärkeimpiä tavoitteita on saavuttaa jatkuvuutta liiketoiminnallaan. Ainoastaan pitkäaikaisella partneruudella voidaan saavuttaa merkittäviä etuja markkinoilla. Siksi on tärkeätä, jo partnerin valinnassa, kiinnittää huomiota partneruuden jatkuvuuteen pitkällä tähtäimellä. Liiketoimintaverkostossa partneruudesta syntyvät tuotot ja niiden jakaminen on tärkein yksittäinen osaalue. Oleellista partneruuden jatkuvuudelle pitkällä tähtäimellä on jo partneria valittaessa se, että kyetään arvioimaan miten partneruudesta syntyvät tuotot jaetaan tasapuolisesti ja onko partneruudesta syntyvälle liiketoiminnalle jatkuvuutta. Jotta partneriverkostolle asetetut tavoitteet voitaisiin saavuttaa, on tärkeää suunnitella partneriverkoston hallintaa myös operatiivisella tasolla. Lisäksi tärkeää on jakaa verkostolle asetetut yhteiset tavoitteet organisaatioiden sisällä. Jos ylemmänja operatiivisen tason johdon yhteistyö on riittämätöntä, se vaikeuttaa oleellisesti asetettujen tavoitteiden saavuttamista. Tiedon jakaminen aikaisessa vaiheessa sitouttaa eri sidosryhmät paremmin yhteisiin tavoitteisiin.
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Integration of biological data of various types and the development of adapted bioinformatics tools represent critical objectives to enable research at the systems level. The European Network of Excellence ENFIN is engaged in developing an adapted infrastructure to connect databases, and platforms to enable both the generation of new bioinformatics tools and the experimental validation of computational predictions. With the aim of bridging the gap existing between standard wet laboratories and bioinformatics, the ENFIN Network runs integrative research projects to bring the latest computational techniques to bear directly on questions dedicated to systems biology in the wet laboratory environment. The Network maintains internally close collaboration between experimental and computational research, enabling a permanent cycling of experimental validation and improvement of computational prediction methods. The computational work includes the development of a database infrastructure (EnCORE), bioinformatics analysis methods and a novel platform for protein function analysis FuncNet.
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Perfusion experiments with horseradish peroxidase have established that the morphological substrate of the blood-brain barrier is represented by microvascular endothelial cells. They are characterized by complexly arranged tight junctions and a very low rate of transcytotic vesicular transport. They express transport enzymes, carrier systems and brain endothelial cell-specific molecules of unknown function not expressed by any other endothelial cell population. These blood-brain barrier properties are not intrinsic to these cells but are inducible by the surrounding brain tissue. Type I astrocytes injected into the anterior eye chamber of the rat or onto the chick chorioallantoic membrane are able to induce a host-derived angiogenesis and some blood-brain barrier properties in endothelial cells of non-neural origin. Recently we have shown that this cellular interaction is due to the secretion of a soluble astrocyte derived factor(s). Astrocytes are also implicated in the maintenance, functional regulation and the repair of the blood-brain barrier. Complex interactions between other constituents of the microenvironment surrounding the endothelial cells, such as the basement membrane, pericytes, nerve endings, microglial cells and the extracellular fluid, take place and are required for the proper functioning of the blood-brain barrier, which in addition is regionally different as reflected by endothelial cell heterogeneity.
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The major objective of this thesis is to describe and analyse how a railcarrier is engaged in an intermodal freight transportation network through its role and position. Because of the fact that the role as a conceptualisation has a lot of parallels with the position, both these phenomena are evaluated theoretically and empirically. VR Cargo (a strategical business unitof the Finnish railway company VR Ltd.) was chosen to be the focal firm surrounded by the actors of the focal net. Because of the fact that networks are sets of relationships rather than sets of actors, it is essential to describe the dimensions of the relationships created through the time thus having a past, presentand future. The roles are created during long common history shared by the actors especially when IM networks are considered. The presence of roles is embeddedin the tasks, and the future is anchored to the expectations. Furthermore, in this study role refers to network dynamics, and to incremental and radical changes in the network, in a similar way as position refers to stability and to the influences of bonded structures. The main purpose of the first part of the study was to examine how the two distinctive views that have a dominant position in modern logistics ¿ the network view (particularly IMP-based network approach) and the managerial view (represented by Supply Chain Management) differ, especially when intermodalism is under consideration. In this study intermodalism was defined as a form of interorganisational behaviour characterized by the physical movement of unitized goods with Intermodal Transport Units, using more than one mode as performed by the net of operators. In this particular stage the study relies mainly on theoretical evaluation broadened by some discussions with the practitioners. This is essential, because the continuous dialogue between theory and practice is highly emphasized. Some managerial implications are discussed on the basis of the theoretical examination. A tentative model for empirical analysis in subsequent research is suggested. The empirical investigation, which relies on the interviews among the members in the focal net, shows that the major role of the focal company in the network is the common carrier. This role has some behavioural and functional characteristics, such as an executive's disclosure expressing strategic will attached with stable and predictable managerial and organisational behaviour. Most important is the notion that the focal company is neutral for all the other operators, and willing to enhance and strengthen the collaboration with all the members in the IM network. This also means that all the accounts are aimed at being equal in terms of customer satisfaction. Besides, the adjustments intensify the adopted role. However, the focal company is also obliged tosustain its role as it still has a government-erected right to maintain solely the railway operations on domestic tracks. In addition, the roles of a dominator, principal, partner, subcontractor, and integrator were present appearing either in a dyadic relationship or in net(work) context. In order to reveal differentroles, a dualistic interpretation of the concept of role/position was employed.
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Activity decreases, or deactivations, of midline and parietal cortical brain regions are routinely observed in human functional neuroimaging studies that compare periods of task-based cognitive performance with passive states, such as rest. It is now widely held that such task-induced deactivations index a highly organized"default-mode network" (DMN): a large-scale brain system whose discovery has had broad implications in the study of human brain function and behavior. In this work, we show that common task-induced deactivations from rest also occur outside of the DMN as a function of increased task demand. Fifty healthy adult subjects performed two distinct functional magnetic resonance imaging tasks that were designed to reliably map deactivations from a resting baseline. As primary findings, increases in task demand consistently modulated the regional anatomy of DMN deactivation. At high levels of task demand, robust deactivation was observed in non-DMN regions, most notably, the posterior insular cortex. Deactivation of this region was directly implicated in a performance-based analysis of experienced task difficulty. Together, these findings suggest that task-induced deactivations from rest are not limited to the DMN and extend to brain regions typically associated with integrative sensory and interoceptive processes.
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Tässä diplomityössä on oletettu että neljännen sukupolven mobiiliverkko on saumaton yhdistelmä olemassa olevia toisen ja kolmannen sukupolven langattomia verkkoja sekä lyhyen kantaman WLAN- ja Bluetooth-radiotekniikoita. Näiden tekniikoiden on myös oletettu olevan niin yhteensopivia ettei käyttäjä havaitse saanti verkon muuttumista. Työ esittelee neljännen sukupolven mobiiliverkkoihin liittyvien tärkeimpien langattomien tekniikoiden arkkitehtuurin ja perustoiminta-periaatteet. Työ kuvaa eri tekniikoita ja käytäntöjä tiedon mittaamiseen ja keräämiseen. Saatuja transaktiomittauksia voidaan käyttää tarjottaessa erilaistettuja palvelutasoja sekä verkko- ja palvelukapasiteetin optimoimisessa. Lisäksi työssä esitellään Internet Business Information Manager joka on ohjelmistokehys hajautetun tiedon keräämiseen. Sen keräämää mittaustietoa voidaan käyttää palvelun tason seurannassa j a raportoinnissa sekä laskutuksessa. Työn käytännön osuudessa piti kehittää langattoman verkon liikennettä seuraava agentti joka tarkkailisi palvelun laatua. Agentti sijaitsisi matkapuhelimessa mitaten verkon liikennettä. Agenttia ei kuitenkaan voitu toteuttaa koska ohjelmistoympäristö todettiin vajaaksi. Joka tapauksessa työ osoitti että käyttäjän näkökulmasta tietoa kerääville agenteille on todellinen tarve.