Quantitative Analysis of Myelin and Axonal Remodeling in the Uninjured Motor Network After Stroke.

Contralesional brain connectivity plasticity was previously reported after stroke. This study aims at disentangling the biological mechanisms underlying connectivity plasticity in the uninjured motor network after an ischemic lesion. In particular, we measured generalized fractional anisotropy (GFA) and magnetization transfer ratio (MTR) to assess whether poststroke connectivity remodeling depends on axonal and/or myelin changes. Diffusion-spectrum imaging and magnetization transfer MRI at 3T were performed in 10 patients in acute phase, at 1 and 6 months after stroke, which was affecting motor cortical and/or subcortical areas. Ten age- and gender-matched healthy volunteers were scanned 1 month apart for longitudinal comparison. Clinical assessment was also performed in patients prior to magnetic resonance imaging (MRI). In the contralesional hemisphere, average measures and tract-based quantitative analysis of GFA and MTR were performed to assess axonal integrity and myelination along motor connections as well as their variations in time. Mean and tract-based measures of MTR and GFA showed significant changes in a number of contralesional motor connections, confirming both axonal and myelin plasticity in our cohort of patients. Moreover, density-derived features (peak height, standard deviation, and skewness) of GFA and MTR along the tracts showed additional correlation with clinical scores than mean values. These findings reveal the interplay between contralateral myelin and axonal remodeling after stroke.

Maintenance process development for remote administration of network servers

Maintenance is a part of system development and it is possible to develop operation models for accomplishing maintenance tasks. These models can be applied to individual maintenance tasks, maintenance projects and version management. Beneficial operation models makes maintenance more effective and they assist in managing various changes. The purpose of this thesis was to develop a maintenance process which can be used to remote administer network servers. This consisted of defining those operation models and technical specifications which enable to set up, manage changes, maintain and monitor resources of information systems that are located in several different sites. At first in this thesis the needs of the process were determined and requirements were defined based on those needs. The meaning of processes in maintenance of information systems, maintenance workflows and challenges were studied. Then current practical problems and disadvantages of maintenance work were analyzed in order to focus the development to proper issues. Because available operation models did not cover all the recent needs, new maintenance process which fulfilled the requirements was developed.

Platform Architectures for Policy-Based Network Access Control

Tämä diplomityö käsittelee sääntöpohjaisen verkkoon pääsyn hallinnan (NAC) ratkaisuja arkkitehtonisesta näkökulmasta. Työssä käydään läpi Trusted Computing Groupin, Microsoft Corporationin, Juniper Networksin sekä Cisco Systemsin NAC-ratkaisuja. NAC koostuu joukosta uusia sekä jo olemassa olevia teknologioita, jotka auttavat ennalta määriteltyyn sääntökantaan perustuen hallitsemaan suojattuun verkkoon pyrkivien laitteiden tietoliikenneyhteyksiä. Käyttäjän tunnistamisen lisäksi NAC pystyy rajoittamaan verkkoon pääsyä laitekohtaisten ominaisuuksien perusteella, esimerkiksi virustunnisteisiin ja käyttöjärjestelmäpäivityksiin liittyen ja paikkaamaan tietyin rajoituksin näissä esiintyviä puutteita verkkoon pääsyn sallimiseksi. NAC on verraten uusi käsite, jolta puuttuu tarkka määritelmä. Tästä johtuen nykymarkkinoilla myydään ominaisuuksiltaan puutteellisia tuotteita NAC-nimikkeellä. Standardointi eri valmistajien NAC-komponenttien yhteentoimivuuden takaamiseksi on meneillään, minkä perusteella ratkaisut voidaan jakaa joko avoimia standardeja tai valmistajakohtaisia standardeja noudattaviksi. Esitellyt NAC-ratkaisut noudattavat standardeja joko rajoitetusti tai eivät lainkaan. Mikään läpikäydyistä ratkaisuista ei ole täydellinen NAC, mutta Juniper Networksin ratkaisu nousee niistä potentiaalisimmaksi jatkokehityksen ja -tutkimuksen kohteeksi TietoEnator Processing & Networks Oy:lle. Eräs keskeinen ongelma NAC-konseptissa on työaseman tietoverkolle toimittama mahdollisesti valheellinen tietoturvatarkistuksen tulos, minkä perusteella pääsyä osittain hallitaan. Muun muassa tähän ongelmaan ratkaisuna voisi olla jo nykytietokoneista löytyvä TPM-siru, mikä takaa tiedon oikeellisuuden ja koskemattomuuden.

Synaptic depression and slow oscillatory activity in a biophysical network model of the cerebral cortex

Short-term synaptic depression (STD) is a form of synaptic plasticity that has a large impact on network computations. Experimental results suggest that STD is modulated by cortical activity, decreasing with activity in the network and increasing during silent states. Here, we explored different activity-modulation protocols in a biophysical network model for which the model displayed less STD when the network was active than when it was silent, in agreement with experimental results. Furthermore, we studied how trains of synaptic potentials had lesser decay during periods of activity (UP states) than during silent periods (DOWN states), providing new experimental predictions. We next tackled the inverse question of what is the impact of modifying STD parameters on the emergent activity of the network, a question difficult to answer experimentally. We found that synaptic depression of cortical connections had a critical role to determine the regime of rhythmic cortical activity. While low STD resulted in an emergent rhythmic activity with short UP states and long DOWN states, increasing STD resulted in longer and more frequent UP states interleaved with short silent periods. A still higher synaptic depression set the network into a non-oscillatory firing regime where DOWN states no longer occurred. The speed of propagation of UP states along the network was not found to be modulated by STD during the oscillatory regime; it remained relatively stable over a range of values of STD. Overall, we found that the mutual interactions between synaptic depression and ongoing network activity are critical to determine the mechanisms that modulate cortical emergent patterns.

Minun, sinun vai meidän? Corporate governance osuustoiminnallisissa pankeissa

Omistajalähtöisen kulttuurin voimistumisen myötä yritysten corporate governance -järjestelmät ovat nousseet keskeiseen asemaan yritysten toiminnassa. Osuustoiminnallisissa yrityksissä demokraattinen hallintotapa ja jäsenten tarpeista nouseva yrityksen tarkoitus luo corporate governance -järjestelmiin haasteita. Tutkielmassa tarkastellaan näitä haasteita osuustoiminnallisissa pankeissa. Keskeinen tutkimustulos oli, että osuustoiminnallisten pankkien corporate governance -järjestelmät eivät täysin huomioi osuuspankkien tarkoitusta.

Making SENSE - Sustained Effort Network for treatment of Status Epilepticus as a multicenter prospective registry.

BACKGROUND: Evidence regarding the different treatment options of status epilepticus (SE) in adults is scarce. Large randomized trials cover only one treatment at early stage and suggest the superiority of benzodiazepines over placebo, of intravenous lorazepam over intravenous diazepam or over intravenous phenytoin alone, and of intramuscular midazolam over intravenous lorazepam. However, many patients will not be treated successfully with the first treatment step. A large randomized trial covering the treatment of established status (ESETT) has just been funded recently by the NIH and will not start before 2015, with expected results in 2018; a trial on the treatment of refractory status with general anesthetics was terminated early due to insufficient recruitment. Therefore, a prospective multicenter observational registry was set up; this may help in clinical decision-making until results from randomized trials are available. METHODS/DESIGN: SENSE is a prospective, multicenter registry for patients treated for SE. The primary objective is to document patient characteristics, treatment modalities and in-house outcome of consecutive adults admitted for SE treatment in each of the participating centres and to identify predictors of outcome. Pre-treatment, treatment-related and outcome variables are documented systematically. To allow for meaningful multivariate analysis in the patient subgroups with refractory SE, a cohort size of 1000 patients is targeted. DISCUSSION: The results of the study will provide information about risks and benefits of specific treatment steps in different patient groups with SE at different points of time. Thus, it will support clinical decision-making and, furthermore, it will be helpful in the planning of treatment trials. TRIAL REGISTRATION: DRKS00000725.

IN DUBIO PRO NATURA? A Philosophical Analysis of the Precautionary Principle in Environmental and Health Risk Governance

In this book, I apply a philosophical approach to study the precautionary principle in environmental (and health) risk decision-making. The principle says that unacceptable environmental and health risks should be anticipated, and they ought to be forestalled before the damage comes to fruition even if scientific understanding of the risks is inadequate. The study consists of introductory chapters, summary and seven original publications which aim at explicating the principle, critically analysing the debate on the principle, and constructing a basis for the well-founded use of the principle. Papers I-V present the main thesis of this research. In the two last papers, the discussion is widened to new directions. The starting question is how well the currently embraced precautionary principle stands up to critical philosophical scrutiny. The approach employed is analytical: mainly conceptual, argumentative and ethical. The study draws upon Anglo-American style philosophy on the one hand, and upon sources of law as well as concrete cases and decision-making practices at the European Union level and in its member countries on the other. The framework is environmental (and health) risk governance, including the related law and policy. The main thesis of this study is that the debate on the precautionary principle needs to be shifted from the question of whether the principle (or its weak or strong interpretation) is well-grounded in general to questions about the theoretical plausibility and ethical and socio-political justifiability of specific understandings of the principle. The real picture of the precautionary principle is more complex than that found (i.e. presumed) in much of the current academic, political and public debate surrounding it. While certain presumptions and interpretations of the principle are found to be sound, others are theoretically flawed or include serious practical problems. The analysis discloses conceptual and ethical presumptions and elementary understandings of the precautionary principle, critically assesses current practices invoked in the name of the precautionary principle and public participation, and seeks to build bridges between precaution, engagement and philosophical ethics. Hence, it is intended to provide a sound basis upon which subsequent academic scrutiny can build.

Building an Access Network for Triple-Play Services

This final project was made for the Broadband department of TeliaSonera. This project gives an overview on how internet service provider might build an access network so that they can offer triple-play services. It also gives information on what equipment is needed and what is required from the access, aggregation and edge networks. The project starts by describing the triple-play service. Then it moves on to optical fiber cables, the network technology and network architecture. At the end of the project there is an example of the process and construction of the access network. It will give an overview of the total process and problems that a network planner might face during the planning phase of the project. It will give some indication on how one area is built from the start to finish. The conclusion of the project presents some points that must be taken into consideration when building an access network. The building of an access network has to be divided to a time span of eight to ten years, where one year is one phase in the project. One phase is divided into three parts; Selecting the areas and targets, Planning the areas and targets, and Documentation. The example area gives indication on the planning of an area. It is almost impossible to connect all targets at the same time. This means that the service provider has to complete the construction in two or three parts. The area is considered to be complete when more than 80% of the real estates have fiber.

Beyond pure public and pure private management models: Partial privatization in the European airport industry

The use of private funding and management is enjoying an increasing trend in airports. The literature has not paid enough attention to the mixed management models in this industry, although many European airports take the form of mixed public-private companies, where ownership is shared between public and private sectors. We examine the determinants of the degree of private participation in the European airport sector. Drawing on a sample of the 100 largest European airports, we estimate a multivariate equation in order to determine the role of airport characteristics, fiscal variables, and political factors on the extent of private involvement. Our results confirm the alignment between public and private interests in partially privatized airports. Fiscal constraints and market attractiveness promote private participation. Integrated governance models and the share of network carriers prevent the presence of private ownership, while the degree of private participation appears to be pragmatic rather than ideological.

International STakeholder NETwork (ISTNET): creating a developmental neurotoxicity (DNT) testing road map for regulatory purposes.

A major problem in developmental neurotoxicity (DNT) risk assessment is the lack of toxicological hazard information for most compounds. Therefore, new approaches are being considered to provide adequate experimental data that allow regulatory decisions. This process requires a matching of regulatory needs on the one hand and the opportunities provided by new test systems and methods on the other hand. Alignment of academically and industrially driven assay development with regulatory needs in the field of DNT is a core mission of the International STakeholder NETwork (ISTNET) in DNT testing. The first meeting of ISTNET was held in Zurich on 23-24 January 2014 in order to explore the concept of adverse outcome pathway (AOP) to practical DNT testing. AOPs were considered promising tools to promote test systems development according to regulatory needs. Moreover, the AOP concept was identified as an important guiding principle to assemble predictive integrated testing strategies (ITSs) for DNT. The recommendations on a road map towards AOP-based DNT testing is considered a stepwise approach, operating initially with incomplete AOPs for compound grouping, and focussing on key events of neurodevelopment. Next steps to be considered in follow-up activities are the use of case studies to further apply the AOP concept in regulatory DNT testing, making use of AOP intersections (common key events) for economic development of screening assays, and addressing the transition from qualitative descriptions to quantitative network modelling.

Corporate governance ja omistajaohjaus - valtioenemmistöiset yhtiöt ja valtion osakkuusyhtiöt

Tutkimuksessa muodostetaan osakeyhtiön corporate governance - viitekehys lähtien sen taustateorioista ja -malleista sekä käsitteistä. Tutkimuksessa tarkastellaan osakeyhtiön yhtiöoikeudellisia toimielimiä sekä niiden tehtäviä ja keskinäisiä suhteita. Tutkimusmetodina käytetään oikeustaloustieteellistä lainoppia. Erityisenä tutkimuskohteena ovat valtioenemmistöiset yhtiöt ja valtion osakkuusyhtiöt. Julkisen sektorin uudelleenorganisoinnin ja tehokkuusvaatimuksien vuoksi valtion omistamien yhtiöiden merkitys tullenee jatkossa kasvamaan. Osakkeenomistajien residuaalisen vaateen perusteella yhtiökokouksella on osakeyhtiön ylin päätösvalta. Yhtiökokous voi kuitenkin lähtökohtaisesti päättää vain sille lain tai yhtiöjärjestyksen mukaan kuuluvista tehtävistä. Hallituksella on yleistoimivalta, jonka perusteella hallitus vastaa kaikista niistä hallinnon tehtävistä, joita ei ole osoitettu muille toimielimille. Toimitusjohtaja vastaa juoksevan hallinnon hoitamisesta sekä kirjanpidon lainmukaisuudesta ja varainhoidon järjestämisestä luotettavalla tavalla. Hallintoneuvoston tehtävät rajoittuvat nykyisin lähinnä yhtiön muun johdon valvontaan. Useimmissa osakeyhtiöissä on oltava myös tilintarkastaja, jonka on tarkastettava yhtiön kirjanpito, tilinpäätös, toimintakertomus ja hallinto. Valtioenemmistöisten yhtiöiden ja valtion osakkuusyhtiöiden yhtiöoikeudellisten toimielinten asema ei lainsäädännön tai corporate governance - suositusten perusteella poikkea muista yhtiöistä. Vaikka yhtiön toimielinten vastuuketju on aiempaa selkeämpi, niin yhtiökäytännössä toimielinten tehtävien tosiasialliset rajat vaihtelevat suuresti riippuen erityisesti yhtiön toiminnan laajuudesta, omistusrakenteesta ja toimialasta.