Control of Coulomb blockade in a mesoscopic Josephson junction using single electron tunneling

We study a circuit where a mesoscopic Josephson junction (JJ) is embedded in an environment consisting of a large bias resistor and a normal metal - superconductor tunnel junction (NIS). The effective Coulomb blockade of the JJ can be controlled by the tunneling current through the NIS junction leading to transistor-like characteristics. We show using phase correlation theory and numerical simulations that substantial current gain with low current noise ($i_{n}\lesssim 1$ fA/$\sqrt{\text{Hz}}$) and noise temperature ($\lesssim$ 0.1 K) can be achieved. Good agreement between our numerical simulations and experimental results is obtained.Comment: 5 pages, 4 figures, RevTE

Description of self-synchronization effects in distributed Josephson junction arrays using harmonic analysis and power balance

Power generation and synchronisation in Josephson junction arrays have attracted attention for a long time. This stems from fundamental interest in nonlinear coupled systems as well as from potential in practical applications. In this paper we study the case of an array of junctions coupled to a distributed transmission line either driven by an external microwave or in a self-oscillating mode. We simplify the theoretical treatment in terms of harmonic analysis and power balance. We apply the model to explain the large operation margins of SNS- and SINIS-junction arrays. We show the validity of the approach by comparing with experiments and simulations with self-oscillating es-SIS junction arrays.Comment: 5 pages, 3 figure

Preface

Non peer reviewe

The Cognitive Atlas: Employing Interaction Design Processes to Facilitate Collaborative Ontology Creation

The Cognitive Atlas is a collaborative knowledge-building project that aims to develop an ontology that characterizes the current conceptual framework among researchers in cognitive science and neuroscience. The project objectives from the beginning focused on usability, simplicity, and utility for end users. Support for Semantic Web technologies was also a priority in order to support interoperability with other neuroscience projects and knowledge bases. Current off-the-shelf semantic web or semantic wiki technologies, however, do not often lend themselves to simple user interaction designs for non-technical researchers and practitioners; the abstract nature and complexity of these systems acts as point of friction for user interaction, inhibiting usability and utility. Instead, we take an alternate interaction design approach driven by user centered design processes rather than a base set of semantic technologies. This paper reviews the initial two rounds of design and development of the Cognitive Atlas system, including interactive design decisions and their implementation as guided by current industry practices for the development of complex interactive systems

Linking past cultural developments to palaeoenvironmental changes in Estonia

Connections between environmental and cultural changes are analysed in Estonia during the past c. 4,500 years. Records of cereal-type pollen as (agri)cultural indices are compared with high-resolution palaeohydrological and annual mean temperature reconstructions from a selection of Estonian bogs and lakes (and Lake Igelsjön in Sweden). A broad-scale comparison shows increases in the percentage of cereal-type pollen during a decreasing trend in annual mean temperatures over the past c. 4,300 years, suggesting a certain independence of agrarian activities from environmental conditions at the regional level. The first cereal-type pollen in the region is found from a period with a warm and dry climate. A slow increase in pollen of cultivated land is seen around the beginning of the late Bronze Age, a slight increase at the end of the Roman Iron Age and a significant increase at the beginning of the Middle Ages. In a few cases increases in agricultural pollen percentages occur in the periods of warming. Stagnation and regression occurs in the periods of cooling, but regression at individual sites may also be related to warmer climate episodes. The cooling at c. 400–300 cal b.p., during the ‘Little Ice Age’ coincides with declines in cereal-type and herb pollen curves. These may not, however, be directly related to the climate change, because they coincide with war activities in the region

What are domestic apples worth? Hedonic responses and sensory information as drivers of willingness to pay

The effects of written information of key sensory characteristics of apple cultivars on hedonic ratings and willingness to pay (WTP) were measured in an experimental auction. Participants (n = 118, 95F, 23M, mean age 37y.) rated, in three subsequent rounds, pleasantness and WTP based on (1) appearance only (n = 25), (2) appearance, written information and tasting (n = 44), or (3) appearance, tasting and written information (n = 49). Four domestic cultivars were described as medium sour and crispy ('Amorosa'), sour and medium crispy ('Konsta'), medium sweet and medium crispy ('Lobo') and sweet and medium crispy ('Tobias'). The differences between the cultivars in pleasantness and WTP were minimal when the evaluation was based on appearance only. The effect of tasting after visual inspection was positive in three cultivars and negative in one ('Konsta'). Written information after tasting did not affect pleasantness or WTP. For one cultivar ('Tobias'), information given before tasting created expectations that were not fulfilled, thus tasting decreased hedonic ratings and WTP. Mean WTP was 2.36 euro/kg. When pleasantness increased by one point, WTP increased by 0.31-0.45 euro/kg. Regression models showed that pleasantness explained 38-55% of WTP. Respondents who reported consuming domestic apples more often than once a week had 0.52-0.74 euro/kg higher WTP than those who consumed them less frequently, suggesting that familiarity with the product increases WTP. Results indicate that both written information and tasting contribute to the ratings of pleasantness and WTP. (C) 2015 Elsevier Ltd. All rights reserved.Postprint (published version

GLP 1 retseptori agonisti liraglutiidi neuroprotektiivne toime Wolframi sündroomi roti mudelis

Väitekirja elektrooniline versioon ei sisalda publikatsiooneWolframi sündroom on haruldane autosomaalse retsessiivse pärandumismustriga haigus, mida põhjustab Wfs1 geeni poolt kodeeritud Wolframiini valgu düsfunktsioon. Wolframi sündroomi esimene sümptom on insuliinist sõltuv diabeet ning sellele järgnevad nägemisnärvi atroofia, magediabeet ja neuroloogilised komplikatsioonid. Insuliinist sõltuv diabeet on kontrollitav insuliini asendusraviga, seega on Wolframi sündroomiga patsientidele enim muret valmistav neurodegeneratsioon, millel puudub ravi. Seepärast on oluline välja töötada neuroprotektiivseid ravimeetodeid, mis oleksid võimelised aeglustama haiguse kulgu ja seeläbi pikendama Wolframi sündroomiga patsientide eluiga. Wolframiini valgu düsfunktsioonist põhjustatud Wolframi sündroomi uurimiseks on meie uurimisrühm loonud Wfs1 KO roti, kelle Wfs1 geeni viies kodeeriv ekson on deleteeritud. Antud doktoritöö eesmärk oli iseloomustada Wfs1 KO roti fenotüüpi, eesmärgiga kasutada seda uute ravistrateegiate väljatöötamisel. Antud töös pöörati erilist tähelepanu Wolframi sündroomiga seotud neurodegeneratsioonile, mida on insuliinist sõltuva diabeediga võrreldes vähe uuritud. Käesolevas doktoritöös selgus, et Wfs1 KO rottidel tekkisid Wolframi sündroomi peamised sümptomid: insuliinist sõltuv diabeet ja neurodegeneratsioon. See näitab, et Wfs1 KO rott on tõepoolest Wolframi sündroomi loommudel ja seda saab kasutada Wolframi sündroomi ravistrateegiate testimiseks. Diabeedivastane ravim liraglutiid kaitses Wfs1 KO rotte glükoositalumatuse tekke eest. Lisaks vähendas ravi liraglutiidiga neuropõletikku oliivituumades, ER-stressi ja neuronite ruumala suurenemist (neuronal swelling). Lisaks oli BDNF-i mimeetikul 7,8-dihüdroksüflavoonil (7,8-DHF) põletikuvastastane toime hipokampusele ja säilitas kognitiivse funktsiooni Wfs1 KO loomadel, kuigi 7,8-DHF-il diabeedivastast toimet ei tuvastatud. Seetõttu võib ravi liraglutiidiga, või liraglutiidi ja 7,8-DHF-i koosmanustamine Wolframi sündroomiga patsientidel olla paljutõotavaks ravistrateegiaks. Prekliinilistest uuringutest inspireerituna on alustatud kliinilist uuringut liraglutiidiga, seega selgitavad edasised uuringud välja liraglutiidi toime Wolframi sündroomiga patsientidele.Wolfram syndrome is a rare hereditary disorder that is caused by biallelic mutations in the WFS1 gene, from which WFS1 (Wolframin) protein is encoded. Wolfram syndrome starts with diabetes mellitus followed by optic nerve atrophy and neurodegeneration. As no effective therapy is available, drug repurposing could be the best therapeutic option because the drugs are already approved and thereby reach patients faster. GLP-1 receptor agonists are used for the treatment of diabetes mellitus and have neuroprotective properties in addition to glucose-lowering effects. Hence, they could also have a potential therapeutic effect for the main symptoms of Wolfram syndrome. In addition to GLP-1 receptor agonists, the neurotrophic factor, such as BDNF mimetic 7,8-dihydroxyflavone (7,8-DHF), has not been studied in connection with Wolfram syndrome. In vivo investigations for drug repurposing would not be possible without well-characterized animal models. Therefore, our research group has created Wfs1 KO rats with an exon 5 disruption. The aim of this dissertation is (i) to evaluate the symptoms of Wolfram syndrome in Wfs1 KO rats and (ii) to use it to test novel treatment strategies for Wolfram syndrome with an emphasis on neurodegeneration. The current thesis demonstrates that Wfs1 KO rats developed the main symptoms of Wolfram syndrome: diabetes mellitus and neurodegeneration. This indicates that the Wfs1 KO rat is indeed a Wolfram syndrome animal model, and it can be used to test treatment strategies for Wolfram syndrome. The anti-diabetic drug liraglutide protected Wfs1 KO rats against development of glucose intolerance. Moreover, liraglutide treatment had a neuroprotective effect in the olive nucleus, as measured by decreased neuroinflammation, ER stress and neuronal swelling. Additionally, BDNF mimetic 7,8-DHF had an anti-inflammatory effect on the hippocampus and maintained cognitive function in Wfs1 KO animals. However, an anti-diabetic effect of 7,8-DHF was not detected. Therefore, liraglutide treatment alone or co-treatment with liraglutide and 7,8-DHF could be promising treatment strategies for Wolfram syndrome patients. Inspired by preclinical studies, a liraglutide clinical trial has been initiated, and further investigations will clarify the effect of liraglutide in Wolfram syndrome patientshttps://www.ester.ee/record=b544988

The Future of Co-Creation

The objective of this article is to provide a brief summary of the key directions in value co-creation research that have emerged in the last 10 years. It points to several emerging streams in value co-creation research including: i) general management perspective; ii) new product development and innovation; iii) virtual customer environments; iv) service science and service-dominant logic (SDL) of marketing; and v) international markets and entrepreneurship, with a focus on the general management and innovation perspectives. In addition, the article points to another emerging new direction focusing on business co-creation. The development of business co-creation frameworks integrating the participatory role of both universities and vibrantly emerging business ecosystems represents a valuable alternative to traditional technology transfer and business administration approaches

The Future of Co-Creation

The objective of this article is to provide a brief summary of the key directions in value co-creation research that have emerged in the last 10 years. It points to several emerging streams in value co-creation research including: i) general management perspective; ii) new product development and innovation; iii) virtual customer environments; iv) service science and service-dominant logic (SDL) of marketing; and v) international markets and entrepreneurship, with a focus on the general management and innovation perspectives. In addition, the article points to another emerging new direction focusing on business co-creation. The development of business co-creation frameworks integrating the participatory role of both universities and vibrantly emerging business ecosystems represents a valuable alternative to traditional technology transfer and business administration approaches