Conditions for waveguide decoupling in square-lattice photonic crystals

We study coupling and decoupling of parallel waveguides in two-dimensional square-lattice photonic crystals. We show that the waveguide coupling is prohibited at some wavelengths when there is an odd number of rows between the waveguides. In contrast, decoupling does not take place when there is even number of rows between the waveguides. Decoupling can be used to avoid cross talk between adjacent waveguides.Comment: 6 pages, 2 figure

Numerical investigation of the conditioning for plane wave discontinuous Galerkin methods

We present a numerical study to investigate the conditioning of the plane wave discontinuous Galerkin discretization of the Helmholtz problem. We provide empirical evidence that the spectral condition number of the plane wave basis on a single element depends algebraically on the mesh size and the wave number, and exponentially on the number of plane wave directions; we also test its dependence on the element shape. We show that the conditioning of the global system can be improved by orthogonalization of the local basis functions with the modified Gram-Schmidt algorithm, which results in significantly fewer GMRES iterations for solving the discrete problem iteratively.Comment: Submitted as a conference proceeding; minor revisio

Satelliittitoiminnan sääntely Suomessa : oikeudellinen käsikirja

Käsikirjassa esitellään keskeisimmät oikeudelliset reunaehdot, jotka koskevat Suomessa tapahtuvaa satelliittitoimintaa. Käsiteltäviä sääntelyn osa-alueita ovat avaruustoiminta (satelliittien lähettäminen avaruuteen, käyttö siellä ja palauttaminen maahan), kaukokartoitus (avaruudesta käsin tapahtuva kuvaaminen), maa-asema- ja tutkatoiminta (maan pinnalla sijaitsevien asemien ja tutkien käyttö) sekä radiotoiminta (satelliittien tietoliikenne). Selvityksen pääpaino on Suomen lainsäädännössä sekä tähän liittyvissä kansainvälisissä määräyksissä. Sääntelyä tarkastellaan yksityisen sektorin ja tutkimuslaitosten satelliittitoiminnan näkökulmasta

Prolyl Oligopeptidase Enhances α-synuclein Dimerization via Direct Protein-Protein Interaction

Peer reviewe

Valta ja rikosoikeudellinen vastuu – tuomioistuinten toimivalta käsitellä valtiojohdon tekemiä kansainvälisiä rikoksia

The criminal jurisdiction of national and international courts over the international crimes of state leadership There are several instances where state leadership can be held criminally liable for international core crimes. In terms of national courts, state leaders can be tried either in their home state or another state. International alternatives include the International Criminal Court, an ad hoc criminal tribunal, a hybrid tribunal or a so-called internationalised tribunal. The jurisdictional basis of each  court rests either in customary law or international arrangements, depending on the court concerned. Each alternative has its pros and cons. The home state typically has numerous jurisdictional bases over crimes perpetrated by its leaders, but its capacity is restricted by politics and the leadership’s constitutional privileges. Trials in home states are also subject to bias. Other states, while being able to ground their jurisdiction in the universality principle, must consider the immunity of foreign state leaders. The significance of  international tribunals has greatly risen since the 1990s, but establishing jurisdiction and securing arrests remain major concerns. International procedures are also often delayed and continue to face challenges based on the principle of legality. The issues noted in the article emphasize that international criminal law is not an effective way to influence present conflicts, and that discussions on criminal liability pertaining to present conflicts are bound to remain speculative

Methane dynamics in different boreal lake types

This study explores the variability in concentrations of dissolved CH<sub>4</sub> and annual flux estimates in the pelagic zone in a statistically defined sample of 207 lakes in Finland. The lakes were situated in the boreal zone, in an area where the mean annual air temperature ranges from −2.8 to 5.9°C. We examined how lake CH<sub>4</sub> dynamics related to regional lake types assessed according to the EU water framework directive. Ten lake types were defined on the basis of water chemistry, color, and size. Lakes were sampled for dissolved CH<sub>4</sub> concentrations four times per year, at four different depths at the deepest point of each lake. We found that CH<sub>4</sub> concentrations and fluxes to the atmosphere tended to be high in nutrient rich calcareous lakes, and that the shallow lakes had the greatest surface water concentrations. Methane concentration in the hypolimnion was related to oxygen and nutrient concentrations, and to lake depth or lake area. The surface water CH<sub>4</sub> concentration was related to the depth or area of lake. Methane concentration close to the bottom can be viewed as proxy of lake status in terms of frequency of anoxia and nutrient levels. The mean pelagic CH<sub>4</sub> release from randomly selected lakes was 49 mmol m<sup>−2</sup> a<sup>−1</sup>. The sum CH<sub>4</sub> flux (storage and diffusion) correlated with lake depth, area and nutrient content, and CH<sub>4</sub> release was greatest from the shallow nutrient rich and humic lakes. Our results support earlier lake studies regarding the regulating factors and also the magnitude of global emission estimate. These results propose that in boreal region small lakes have higher CH<sub>4</sub> fluxes per unit area than larger lakes, and that the small lakes have a disproportionate significance regarding to the CH<sub>4</sub> release

Erosion-oxidation of pressure vessel steel P265GH

The behaviour of pressure vessel steel P265GH was studied in a centrifugal high-temperature erosion apparatus under impacts by silica (SiO2) particles moving at velocities ranging from 20 to 60 m s-1 and contacting the surface at the angles of 30° and 90°. Besides particle impacts, the steel was simultaneously exposed to air and elevated temperatures of 350 and 450°C. For comparison, the tests were also performed in the absence of erodent particles. After the tests, the material behaviour was evaluated in terms of occurred weight changes and surface characteristics, the latter ones of which were investigated by using, for example, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). In the analysis of the test results, special attention was paid to the composition and microstructure of the used silica particles and how these influence the elemental distribution on the exposed surfaces. The results show that the particle impacts introduce weight losses that follow a ductile angle-dependency, i.e., relatively greater weight losses at the shallow than at the steep impact angle. Although evident oxide scales developed on the surfaces at the test temperatures, they did not provide the steel with protection against particle impacts. Particle debris was detected embedded in the surfaces particularly under impacts at 90°, with softer particle constituents being preferentially deposited. These results are discussed in terms of the erosion-oxidation behaviour of the steel and the consequences of the heterogeneous erodent particle quality