Increasing thermoelectric performance using coherent transport

We show that coherent electron transport through zero-dimensional systems can be used to tailor the shape of the system's transmission function. This quantum-engineering approach can be used to enhance the performance of quantum dots or molecules in thermal-to-electric power conversion. Specifically, we show that electron interference in a two-level system can substantially improve the maximum thermoelectric power and the efficiency at maximum power by suppressing parasitic charge flow near the Fermi energy, and by reducing electronic heat conduction. We discuss possible realizations of this approach in molecular junctions or quantum dots.Comment: 4+ pages, 4 figure

The value of reliability

We derive the value of reliability in the scheduling of an activity of random duration, such as travel under congested conditions. We show that the minimal expected cost is linear in the mean and standard deviation of duration, regardless of the form of the standardized distribution of durations. This insight provides a unification of the scheduling model and models that include the standard deviation of duration directly as an argument in the cost or utility function. The results generalize approximately to the case where the mean and standard deviation of duration depend on the starting time. Empirical illustration is provided.

A new information theoretical measure of global and local spatial association

In this paper a new measure of spatial association, the S statistics, is developed. The proposed measure is based on information theory by defining a spatially weighted information measure (entropy measure) that takes the spatial configuration into account. The proposed S-statistics has an intuitive interpretation, and furthermore fulfills properties that are expected from an entropy measure. Moreover, the S statistics is a global measure of spatial association that can be decomposed into Local Indicators of Spatial Association (LISA). This new measure is tested using a dataset of employment in the culture sector that was attached to the wards over Stockholm County and later compared with the results from current global and local measures of spatial association. It is shown that the proposed S statistics share many properties with Moran's I and Getis-Ord Gi statistics. The local Si statistics showed significant spatial association similar to the Gi statistic, but has the advantage of being possible to aggregate to a global measure of spatial association. The statistics can also be extended to bivariate distributions. It is shown that the commonly used Bayesian empirical approach can be interpreted as a Kullback-Leibler divergence measure. An advantage of S-statistics is that this measure select only the most robust clusters, eliminating the contribution of smaller ones composed by few observations and that may inflate the global measure.Global and local measure of spatial association, LISA, S-statistics, Gi statistics, Moran's I, Kullback-Leibler divergence,

Understanding the length dependence of molecular junction thermopower

Thermopower of molecular junctions is sensitive to details in the junction and may increase, decrease, or saturate with increasing chain length, depending on the system. Using McConnell's theory for exponentially suppressed transport together with a simple and easily interpretable tight binding model, we show how these different behaviors depend on the molecular backbone and its binding to the contacts. We distinguish between resonances from binding groups or undercoordinated electrode atoms, and those from the periodic backbone. It is demonstrated that while the former gives a length-independent contribution to the thermopower, possibly changing its sign, the latter determines its length dependence. This means that the question of which orbitals from the periodic chain that dominate the transport should not be inferred from the sign of the thermopower but from its length dependence. We find that the same molecular backbone can, in principle, show four qualitatively different thermopower trends depending on the binding group: It can be positive or negative for short chains, and it can either increase or decrease with length

Kyselytutkimus Vaasan kaupungin pilaantuneiden maa-alueiden rekisterin kehittämiseksi

Tämä kyselytutkimus on tehty Vaasan kiinteistötoimen toimeksiannosta. Kiinteistötoimi hallinnoi Vaasan kaupungin omistuksessa olevien pilaantuneiksi epäiltyjen ja pilaantuneiden maa-alueiden kunnostuksia ja tutkimuksia. Selvityksen tarkoitus on perehtyä Vaasan pilaantuneiden maa-alueiden rekisterin toimivuuteen ja ongelmakohtiin, ja muodostaa sille kehitysehdotuksia. Teoriaosuudessa on käsitelty pilaantuneita maa-alueita sekä niiden hallinnan ja tutkimisen nykytilaa sekä Suomessa että Vaasassa. Teoriaosuudessa on kuvattu myös tämän selvityksen olennaiset käsitteet. Kyselytutkimuksen avulla tutustuttiin kyselykaupunkien pilaantuneiden maa-alueiden rekistereihin ja -hallintaan. Kyselyn tuloksia verrattiin Vaasan vastaaviin ratkaisuihin ja muodostettiin niistä johtopäätöksiä Vaasan rekisterin kehittämiseksi. Vaasan pilaantuneiden maa-alueiden rekisterin teknisiä ominaisuuksia sekä sen käytettävyyttä on mahdollista kehittää. Samalla yhteistyötä valtion viranomaisten kanssa tulee lisätä ja sitä kautta laajentaa rekisterin osuutta pilaantuneita maa-alueita koskevassa päätöksenteossa. Pilaantuneiden maa-alueiden rekisterin kehittämistyötä ei Vaasassa kannata varsinaisesti aloittaa, ennen kuin valtion Maaperän tilan tietojärjestelmän rajapintapalvelu on otettu käyttöön.This survey was made by the commission of Vaasa city’s real-estate unit. The real-estate unit governs the land areas owned by the city that are suspected to be contaminated as well as the restoration and investigation of the contaminated lands. The aim of this survey was to examine the functionality and problems of the register maintained by the real-estate unit and create suggestions for development. The theory part discusses contaminated lands and their current state of control and research, both in Finland and Vaasa. The theory part also includes the relevant ideas of this thesis. The registers of the contaminated lands and the management of the registers in various cities was studied using a questionnaire. The results of this questionnaire were compared with the corresponding results of Vaasa and conclusions were formed for the possible improvement of the register in Vaasa. The technical properties and the user-friendliness of the contaminated land register in Vaasa can be improved. At the same time, the co-operation with the government officials must be increased and through that increase the part of the register in decision-making considering the contaminated lands. It is not necessarily reasonable to start the development of the register in Vaasa before the interface of the national soil information system is in use

Platelet transfusions in hematological disorders

Platelets are important for clot formation and vascular integrity. Thrombocytopenic patients with hematological disorders are at risk of bleeding and platelet transfusions are important in supportive care and treatment of lite-threatening bleedings. Transfusion response in terms of platelet increment is highly variable and hard to predict in the individual patient. Platelet transfusion refractoriness is often due to non-immune factors such as fever, bleeding or infection. Of the immune-causes, antibodies against Human Leukocyte Antigen (HLA) class I is the most common, and these patients can receive HLA-matched platelet transfusions. In a more experimental approach HLA deficient platelets are created by acid treatment. The overall aim of this thesis was to gain a better knowledge of factors affecting platelet transfusion outcome and platelet function, and to improve transfusion practice to patients with platelet refractoriness due to anti-HLA antibodies. In the included research papers, we focused on platelet function and clot formation in patients before and after platelet transfusion (paper I), response to HLA matched platelet transfusions (paper II) and function and survival of HLA deficient platelets (paper III and IV). In paper I, we evaluated the effect of platelet transfusions in 40 hematology patients, measuring platelet count increment, clot formation and response to agonist activation. Platelet count increment correlated with improved clot formation, but the response was highly variable and 34 % of the patients did not respond to the transfusion. In responder patients, efficient clot formation was predicted by good platelet responsiveness to agonist stimulation, but transfusion did not, however, restore platelet function to that of healthy controls. In paper II we evaluated HLA matched platelet transfusions to platelet refractory hematology patients. We found that selection of platelets with either a complete HLA match, or an acceptable HLA mismatch, was highly predictable for a successful transfusion response. For HLA- mismatched transfusions, the degree of matching correlated with the fraction of successful transfusions. Many transfusions were successful despite the presence of donor-specific antibodies (DSAs). In paper III we evaluated the function of HLA deficient platelets after acid treatment and found that they were viable with a normal upregulation of activation markers. The HLA deficient platelets aggregated to a similar extent as untreated platelets in response to stimulation with agonists. Acid treatment removed 70 to 90% of all HLA Class I complexes, which was followed by protection from anti-HLA antibody-mediated complement lysis and reduced phagocytosis by monocytes in vitro. In paper IV we further evaluated the function of HLA deficient platelets in whole transfusion units and investigated the survival of HLA deficient platelets in a mouse model. Recovery, HLA reduction, and viability in acid-treated platelet bags were comparable to the small-scale treatment protocol, and platelets contributed normally to clot formation. The HLA deficient platelets also contributed to endothelial integrity. Acid-treated platelets showed a lower in vivo recovery compared to untreated platelets in the mouse model. They were protected from rejection by single HLA allele-specific antibodies, but still cleared by a pan-HLA antibody. In summary, the results and conclusions presented in this thesis provide a basis for adjusted transfusion practices and several hypotheses for future research. Our results also take HLA deficient platelets closer to a clinical trial

QmeQ 1.0: An open-source Python package for calculations of transport through quantum dot devices

QmeQ is an open-source Python package for numerical modeling of transport through quantum dot devices with strong electron-electron interactions using various approximate master equation approaches. The package provides a framework for calculating stationary particle or energy currents driven by differences in chemical potentials or temperatures between the leads which are tunnel coupled to the quantum dots. The electronic structures of the quantum dots are described by their single-particle states and the Coulomb matrix elements between the states. When transport is treated perturbatively to lowest order in the tunneling couplings, the possible approaches are Pauli (classical), first-order Redfield, and first-order von Neumann master equations, and a particular form of the Lindblad equation. When all processes involving two-particle excitations in the leads are of interest, the second-order von Neumann approach can be applied. All these approaches are implemented in QmeQ. We here give an overview of the basic structure of the package, give examples of transport calculations, and outline the range of applicability of the different approximate approaches.Comment: 34 pages, 10 figure

Розвиток апаратного забезпечення інформатизації педагогічних вищих навчальних закладів України (кінець ХХ - початок ХХІ століття)

У статті проводиться дослідження історії комплектування комп’ютерною технікою, телекомунікаційним обладнанням та технологічним забезпеченням характерних представників педагогічних вищих навчальних закладів України протягом 1980-2010 років. З’ясовані причини прийняття та реалізації рішень у таких вишах про використання інформаційних систем навчального закладу. Встановленні часові рамки основних періодів розвитку апаратного забезпечення інформатизації педагогічних вишів у визначеному історичному періоді

Diplomats or Defendants? Defining the Future of Head-of-State Immunity

Fluorescence nanoscopy provides means to discernthe finer details of protein localization and interaction in cells by offeringan order of magnitude higher resolution than conventional optical imagingtechniques. However, these super resolution techniques put higher demands onthe optical system as well as on the fluorescent probes, making multicolorfluorescence nanoscopy a challenging task. Here we present a new and simpleprocedure which exploits the photostability and excitation spectra of dyes toincrease the number of simultaneous recordable targets in STED nanoscopy. Weuse this procedure to demonstrate four color STED imaging of platelets with ≤40 nm resolution and low crosstalk. Platelets can selectively store, sequesterand release a multitude of different proteins, and in a manner specific fordifferent physiological and disease states. By applying multicolor nanoscopy tostudy platelets, we can achieve spatial mapping of the protein organizationwith a high resolution, for multiple proteins at the same time and in the samecell. This provides a means to identify specific platelet activation states fordiagnostic purposes and to understand the underlying protein storage andrelease mechanisms. We studied the organization of the pro- and anti-angiogenicproteins VEGF and PF-4 together with fibrinogen and filamentous actin, andfound distinct features in their respective protein localization. Further,colocalization analysis revealed only minor overlap between the proteins VEGFand PF-4 indicating that they have separate storage and release mechanisms,corresponding well with their opposite rules as pro- and anti-angiogenicproteins, respectively.Updated from "Submitted" to "Published". QC 20140630</p