Ga Sublattice Defects in (Ga,Mn)As: Thermodynamical and Kinetic Trends

We have used positron annihilation spectroscopy and infrared absorption measurements to study the Ga sublattice defects in epitaxial Ga1−xMnxAs with Mn content varying from 0% to 5%. We show that the Ga vacancy concentration decreases and As antisite concentration increases with increasing Mn content. This is in agreement with thermodynamical considerations for the electronic part of the formation energy of the Ga sublattice point defects. However, the absolute defect concentrations imply that they are determined rather by the growth kinetics than by the thermodynamical equilibrium. The As antisite concentrations in the samples are large enough to be important for compensation and magnetic properites. In addition, the Ga vacancies are likely to be involved in the diffusion and clustering of Mn at low annealing temperatures.Peer reviewe

Evolutionary multi-stage financial scenario tree generation

Multi-stage financial decision optimization under uncertainty depends on a careful numerical approximation of the underlying stochastic process, which describes the future returns of the selected assets or asset categories. Various approaches towards an optimal generation of discrete-time, discrete-state approximations (represented as scenario trees) have been suggested in the literature. In this paper, a new evolutionary algorithm to create scenario trees for multi-stage financial optimization models will be presented. Numerical results and implementation details conclude the paper

Jätebunkkerin rakennesuunnittelun lähtötiedot ja erityiskysymykset

Tiivistelmä. Tämän opinnäytetyön tavoitteena oli tarkentaa jätteenpolttolaitoksien jätebunkkereiden rakennesuunnittelun lähtötietoja ja selvittää niiden taustalla olevaa teoriaa. Lähtötietojen konservatiiviset arviot eivät mahdollista rakenteiden optimointia. Tarvittavia jätteen ominaisuuksia on suomen- ja englanninkielisessä kirjallisuudessa käsitelty vain perinteisen kaatopaikkaläjityksen kontekstissa, joten työ on aihepiirin ensimmäinen. Arvioiden mukaan Euroopan nykyinen jätteenpolttolaitoskapasiteetti mahdollistaa noin 330 uuden jätevoimalaitoksen rakentamisen, joten aihe on ajankohtainen. Työssä käsitellään siiloja koskevan standardin teoriapohjaa ja sen mukaisten painelaskujen soveltuvuutta jätebunkkerin suunnitteluun. Tämän jälkeen selvitetään jätteen mekaanisia ominaisuuksia ja niiden määrittämisen problematiikka. Toisessa osiossa selvitetään jätteen kompostoitumisen tuottamaa lämpöä, jätteen lämmönjohtavuutta ja ominaislämpökapasiteettia sekä näiden määrittämiseen liittyviä ongelmia. Kolmanneksi käsitellään jätteen aiheuttaman kemiallisen rasituksen määrää ja arvioinnin vaikeutta sekä rasituksen vaikutusta bunkkerin betonirakenteisiin. Työ rajautuu näiden lähtötietojen määritykseen eurooppalaisten standardien puitteissa. Lähtötietojen tarkennuksen ei katsottu olevan mahdollista pelkän aiemman tutkimuksen pohjalta, vaan myös käytännön mittauksia jätteen mekaanisista ja lämpöteknisistä ominaisuuksista sekä kemiallisen rasituksen aggressiivisuudesta tulee rakenteiden optimoinnin mahdollistamiseksi suorittaa. Työn tulokseksi muodostui kattava selvitys eri aiheiden ongelmakentistä, teoriasta, tutkimuksen tilasta ja jatkotutkimustarpeista.Initial data and special questions for structural design of waste bunker. Abstract. The goal of this thesis was to define initial data for structural design of waste bunkers in waste incineration plants more accurately and to clarify the underlying theory. Mere conservative estimates of initial data don’t enable structural optimizing. In Finnish and English literature, the needed properties of waste are only discussed in a traditional landfilling context, hence this work is a first on the subject. According to estimates, Europe’s current waste incineration power plant capacity allows about 330 new waste power plants to be build, so the topic is timely. The thesis first discusses a theory base of standard of silos and a suitability of waste load calculations for waste bunker design made according to it. After this, waste’s mechanical properties and problematics of defining them are discussed. Secondly discussed are waste’s heat generation due to composting, thermal conductivity, specific heat capacity and issues to define them. Thirdly, amount of chemical load from waste and difficulties to estimate it, are discussed with their effect on bunker’s concrete structures. The study is limited to a definition of above-mentioned initial data in a frame of European standards. More accurate definition of initial data was not seen possible when it’s only based on prior research. Hence, measurements in practice are needed from waste’s mechanical properties, thermal properties and chemical aggressivity to enable structural optimization. Outcome of the thesis formed to be an extensive study about issues, theories, state of research and about further needs of research on the subject

Impact of gestational diabetes mellitus on the duration of breastfeeding in primiparous women : an observational cohort study

Background The impact of gestational diabetes mellitus (GDM) on the duration of breastfeeding varies between shortening and no impact. Breastfeeding seems to reduce both maternal and offspring risk for type 2 diabetes and offspring risk for overweight or obesity later in life. The aim of our study was to evaluate in primiparous women whether GDM had an influence on the duration of breastfeeding, and further, to evaluate the factors that influenced on the duration of breastfeeding. Methods The study cohort (N = 1089) consisted of all primiparous women with a Finnish background excluding women with pre-existing diabetes mellitus who lived in the city of Vantaa, Finland, gave birth to a singleton living child between 2009 and 2015, and with valid data on breastfeeding available. The diagnosis of GDM was based on a standard 75 g 2-h oral glucose tolerance test. Data were obtained from Finnish national registers and from the medical records of the city of Vantaa. Results No differences were observed in the duration of breastfeeding between women diagnosed with GDM and without GDM, 7.5 (Standard Deviation [SD] 3.7) months versus 7.9 (SD 3.5) months (p = 0.17). Women diagnosed with GDM breastfed boys for a longer duration than girls (maternal age, pre-pregnancy body mass index, marital status, educational attainment, duration of pregnancy, and smoking habits adjusted p = 0.042). Women who breastfed <6 months were younger, were more likely smokers, had shorter education, and higher pre-pregnancy body mass index than women who breastfed over 6 months (p <0.001 for linearity). Conclusions In primiparous women GDM did not influence breastfeeding duration. The positive health effects of breastfeeding should be emphasized especially in young, overweight and less educated women in order to minimize the risk of obesity and type 2 diabetes for themselves and their offspring.Peer reviewe

Impact of sunshine on the risk of gestational diabetes mellitus in primiparous women

ABSTRACTThere is a lack of data about the influence of sunshine hours on the prevalence for gestational diabetes mellitus (GDM). The aim of this study was to evaluate whether the prevalence of GDM varied according to hours of daily sunshine during the first trimester. The study cohort (N = 6189) consists of all primiparous women with a Finnish background who delivered between 2009 and 2015 living in Vantaa city, Finland. Data on births and maternal characteristics were obtained from National Health Registers. Data on sunshine hours were obtained from the Finnish Meteorological Institute. Individual daily sunshine hours during the first trimester of pregnancy were calculated for each woman. Diagnosis of GDM was based on a standard 75-g 2-h glucose tolerance test (OGTT). No relationship was observed between month of conception and GDM. Daily sunshine hours during the first trimester and GDM showed a U-shaped association (adjusted p-value 0.019). In OGTT, a U-shaped association was observed between 0-h glucose value and daily sunshine hours during the first trimester (p = 0.039) as well as with the 1-h glucose value (p = 0.012), respectively. In primiparous women daily sunshine hours during the first trimester showed a U-shaped association with the prevalence of GDM independent of pre-pregnancy risk factors.Abbreviations: BMI: body mass index; GDM: gestational diabetes mellitus; OGTT: standard 75 g 2-h glucose tolerance test; SD: standard deviationPeer reviewe

Drug purchases prior to conception and the risk of gestational diabetes mellitus

Publisher Copyright: © The Author(s) 2022.Objective: Some drugs have adverse effects on glucose metabolism, but it is unknown whether prescription drugs used prior to conception influence the future risk of gestational diabetes mellitus (GDM). Our study evaluated whether the purchase of prescription drugs 6 months prior to conception was associated with the occurrence of GDM. Methods: This cohort study enrolled women with a Finnish background who delivered between 2009 and 2015 in the city of Vantaa, Finland (N = 10,455). Data on maternal characteristics and prescription drug purchases were obtained from national health registers. The use of a unique personal identification number enabled us to combine the register data on an individual level. Results: Six months prior to conception, women who had pregnancies complicated by GDM purchased more prescription drugs than women without GDM (1.38 ± 2.04 vs. 1.11 ± 1.80). The GDM risk was higher in women with higher numbers of prescription purchases and those with more than three deliveries. Conclusions: Multiparous women who purchase several prescription drugs should be given personalized counseling to prevent GDM.Peer reviewe

Impact of smoking on gestational diabetes mellitus and offspring birthweight in primiparous women

Introduction Smoking has been shown to affect glucose homeostasis and increase the risk for type 2 diabetes mellitus. Further, gestational diabetes mellitus (GDM) and smoking are known to influence offspring birthweight. The effect of smoking on glucose homeostasis in pregnancy is less studied and the findings are inconsistent. The aim of this study was to evaluate the effect of smoking on risk for GDM and to evaluate the impact of smoking and GDM on offspring birthweight. Material and methods This is an observational cohort study encompassing 4111 Finnish primiparous women from the city of Vantaa, Finland, who delivered a singleton child between 2009 and 2015. Data were obtained from Finnish national registers. Study participants had complete oral glucose tolerance test results and were divided into three groups according to smoking status: non-smokers (I), smokers who quit during first trimester (II), and smokers who continued after first trimester (III). Results Prevalence of GDM was 19.8%, 24.3%, and 26.6% in non-smokers, those who quit, and those who continued after the first trimester, respectively (P = .004 for differences between groups). The odds ratio for GDM in smokers who continued after the first trimester compared with non-smokers was 1.65 (95% CI 1.09-2.57) after adjustments for age, prepregnancy body mass index, education, and cohabitation. In women without GDM, offspring birthweight was lowest in those who continued smoking after the first trimester (P = .010 for differences between groups). In women with GDM, smoking status did not influence offspring birthweight. Conclusions Smoking during pregnancy is associated with an increased risk for GDM. Offspring birthweight is lowest in women who continue smoking after the first trimester. If pregnancy is complicated by GDM, offspring birthweight is not influenced by smoking.Peer reviewe

Impact of maternal height and gestational diabetes mellitus on offspring birthweight

Aims: To evaluate the impact of gestational diabetes mellitus (GDM) and maternal height on offspring birthweight. Methods: This is an observational cohort study, encompassing 4 111 Finnish primiparous women from Vantaa city, Finland, with singleton deliveries between 2009 and 2015. Data were obtained from the Finnish Medical Birth Register. The study population was divided into five groups according to maternal height. Cut-offs for height levels were I = 173 cm. The main outcome measure was offspring birthweight, expressed as Z-scores according to sex and gestational age. Results: Independently, both maternal height and GDM increased offspring birthweight (p <0.001 for height and GDM). When studying the interaction, a significant increase in offspring birthweight was noted only in extreme height categories; group I = 173 cm (p <0.001) and the impact was similar in both sexes. Maternal height had no impact on offspring ponderal index (p = 0.20 for trend). Conclusions: In extreme height categories, short and tall primiparous women with GDM are at risk for delivering larger offspring compared to women without GDM of similar height. (C) 2019 Elsevier B.V. All rights reserved.Peer reviewe

Lamina-associated polypeptide 2 alpha is required for intranuclear MRTF-A activity

Myocardin-related transcription factor A (MRTF-A), a coactivator of serum response factor (SRF), regulates the expression of many cytoskeletal genes in response to cytoplasmic and nuclear actin dynamics. Here we describe a novel mechanism to regulate MRTF-A activity within the nucleus by showing that lamina-associated polypeptide 2 alpha (Lap2 alpha), the nucleoplasmic isoform of Lap2, is a direct binding partner of MRTF-A, and required for the efficient expression of MRTF-A/SRF target genes. Mechanistically, Lap2 alpha is not required for MRTF-A nuclear localization, unlike most other MRTF-A regulators, but is required for efficient recruitment of MRTF-A to its target genes. This regulatory step takes place prior to MRTF-A chromatin binding, because Lap2 alpha neither interacts with, nor specifically influences active histone marks on MRTF-A/SRF target genes. Phenotypically, Lap2 alpha is required for serum-induced cell migration, and deregulated MRTF-A activity may also contribute to muscle and proliferation phenotypes associated with loss of Lap2 alpha. Our studies therefore add another regulatory layer to the control of MRTF-A-SRF-mediated gene expression, and broaden the role of Lap2 alpha in transcriptional regulation.Peer reviewe

A Study of Degenerate Four-quark states in SU(2) Lattice Monte Carlo

The energies of four-quark states are calculated for geometries in which the quarks are situated on the corners of a series of tetrahedra and also for geometries that correspond to gradually distorting these tetrahedra into a plane. The interest in tetrahedra arises because they are composed of {\bf three } degenerate partitions of the four quarks into two two-quark colour singlets. This is an extension of earlier work showing that geometries with {\bf two} degenerate partitions (e.g.\ squares) experience a large binding energy. It is now found that even larger binding energies do not result, but that for the tetrahedra the ground and first excited states become degenerate in energy. The calculation is carried out using SU(2) for static quarks in the quenched approximation with $\beta=2.4$ on a $16^3\times 32$ lattice. The results are analysed using the correlation matrix between different euclidean times and the implications of these results are discussed for a model based on two-quark potentials.Comment: Original Raw PS file replace by a tarred, compressed and uuencoded PS fil