Search results for "APS"

Hall effect and electronic structure of films

2010

Abstract Tunneling experiments have shown that in order to retain half-metallicity at room temperature not only a large gap is required but also a Fermi energy considerably distant from the minority band edges. We correlate the position of the Fermi energy in the spin minority gap obtained from band structure calculations to Hall effect experiments. As a model system we chose Co 2 Fe x Mn 1 - x Si , where the Fermi energy was calculated to move from the valence band edge of the minority states to the conduction band edge with increasing x . On high quality laser ablated epitaxial films we observe a sign change of both the normal and the anomalous Hall effect with doping. The experimental da…

A comprehensive study of structure and properties of nanocrystalline zinc peroxide

2022

Abstract Nanocrystalline zinc peroxide (nano-ZnO2) was synthesized through a hydrothermal process and comprehensively studied using several experimental techniques. Its crystal structure was characterized by X-ray diffraction, and the average crystallite size of 22 nm was estimated by Rietveld refinement. The temperature-dependent local environment around zinc atoms was reconstructed using reverse Monte Carlo (RMC) analysis from the Zn K-edge X-ray absorption spectra. The indirect band gap of about 4.6 eV was found using optical absorption spectroscopy. Lattice dynamics of nano-ZnO2 was studied by infrared and Raman spectroscopy. In situ Raman measurements indicate the stability of nano-ZnO…

Traps N' Clots: NET-Mediated Thrombosis and Related Diseases.

2020

Lasten ja nuorten aikuisten kokemuksia vuoroasumiseen liittyvästä päätöksenteosta

2020

Artikkeli keskittyy lasten kokemuksiin ja osallisuuteen vuoroasumiseen liittyvässä päätöksenteossa. Laadullinen pitkittäisaineisto koostuu vuoroasuvien lasten ja samoille henkilöille nuorina aikuisina tehdyistä haastatteluista. Teoreettisena lähtökohtana on John Agnew’n (2002) ajattelu ihmisen päätöksentekoon samanaikaisesti vaikuttavista yksilöllisistä ja yhteisöllisistä motiiveista. Vuoroasuminen näyttäytyi moninaisena ja muuttuvana järjestelynä. Haastatellut kokivat olleensa mukana vaikuttamassa vuoroasumista koskevassa päätöksenteossa, vaikka vanhemmat olivatkin useimmiten päättäneet asumisen periaatteesta. He pitivät tärkeänä, että lapset saavat halutessaan osallistua päätöksentekoon j…

Adolescent use of social media and associations with sleep patterns across 18 European and North American countries

2023

Objective Over the past decade, concurrent with increasing social media use (SMU), there has been a shift toward poorer sleep among adolescents in many countries. The purpose of this study was to examine the cross-national associations between adolescent SMU and sleep patterns, by comparing 4 different categories of SMU (nonactive, active, intense, and problematic use). Design, setting, and participants Data were from 86,542 adolescents in 18 European and North American countries that participated in the 2017/18 Health Behaviour in School-aged study. Measurements Mixed-effects linear regression models were used to examine cross-national associations between 4 SMU categories and adolescent s…

Tutkimusta lasten kanssa

2023

Artikkelissa tarkastellaan lasten ja tutkijoiden välisiä sukupolvisuhteita tutkimustoiminnassa. Tutkimusmenetelmänä ja tutkijoihin kohdistuvana pedagogisena menetelmänä käytetään kollaboratiivista autoetnografiaa. Artikkelissa hyödynnetään Pierre Bourdieun episteemisen refleksiivisyyden ajatusta eli tutkijan ja tutkittavien suhteiden ja asemien kriittistä arviointia. Lisäksi tutkimustoiminnassa toteutuvia sukupolvisuhteita tarkastellaan eksistentiaalisen, episteemisen ja juridis-eettisen ulottuvuuden avulla. Tutkimusaineisto koostuu tutkijoiden kirjoittamista autoetnografisista teksteistä sekä lapsille suunnattujen työpajojen litteraateista. Analyysi osoittaa, miten tärkeää on hahmottaa las…

Determination of type A and type B trichothecenes in paprika and chili pepper using LC-triple quadrupole-MS and GC-ECD.

2011

There is a need to develop sensitive and accurate analytical methods for determining deoxynivalenol (DON), HT-2 toxin and T-2 toxin in paprika to properly assess the relevant risk of human exposure. An optimized analytical method for determination of HT-2 toxin and T-2 toxin using capillary gas chromatography with electron capture detection and another method for determination of DON by liquid chromatography-mass spectrometry in paprika was developed. The method for determination of HT-2 toxin and T-2 toxin that gave the best recoveries involved extraction of the sample with acetonitrile-water (84:16, v/v), clean-up by solid-phase extraction on a cartridge made of different sorbent material…

Quaternary transition pathway in sol–gel encapsulated haemoglobin tracked by NIR and UV spectral relaxations

2008

→T structural transition of haemoglobin (hb), the protein responsible for oxygen (o) transport in the red blood cells of vertebrates, is the hall mark example. This transition, which regu lates o2 uptake in the lungs and o2 release in the tissues, is a switch in the quaternary structure of the protein from a low-affinity state (T) to a high-affinity state (R), two well-characterised structures. The struc tural pathway connecting the end states of this transition remains unclear, however, although recently several experimental 1 or

Strain differences in the ratio of synaptic body types in photoreceptors of the rat retina.

1993

In the retinal outer plexiform layer of seven different rat strains, synaptic bodies (SB) were counted and, according to their morphology, characterized as synaptic ribbons (SR), synaptic spheres (SS) or intermediate structures. It was found that absolute SB numbers showed relatively small variations while SR/SS ratios differed considerably between the strains investigated. These results are discussed with respect to retinal pigmentation and to formation and degradation, respectively, of synaptic ribbons.

Airborne birch pollen in Poland and Latvia in the light of data obtained from aerobiological monitoring and tauber traps in relation to mean air temp…

2012

Birch pollen contains allergens belonging to those with the strongest allergenic properties. In order to trace pollen season patterns of this taxon and pollen annual sums at a wider regional scale, cooperation was established with the University of Latvia in Riga (Latvia). A comparison of the results obtained in the years 2003-2008 in Lublin and in Riga, using volumetric samplers, shows that there was a similar trend in the abundance of birch pollen. The highest sums were noted at both sites in 2003. In all the study years, more birch pollen grains were recorded in Lublin than in Riga, on the average by 7110. The birch pollen seasons started earlier in Lublin than in Riga, on the average by…