Patterns of twinning for Swedish women, 1961-1999

The Nordic population registers provide a unique possibility to study the demographic behavior of small population groups and rare events. In this paper, we study the childbearing behavior of Swedish mothers of twins between 1961 and 1999, inclusive. The twinning rate has increased since the mid-1970s in response to a growing use of fertility-stimulating treatments such as in-vitro fertilization. Such medical procedures are applied mainly to women beyond prime childbearing ages. Nevertheless, we find no simple age pattern in twinning rates. They do not just increase with the woman´s age. Our most consistent finding is that mothers of twins wait noticeably longer than women with singletons before they have another child. This apart, mothers with twins at their first birth have next-birth fertility patterns very similar to women who have two singletons at their first two births. This commonality in childbearing behavior does not extend to higher-order births, though. For mothers with a singleton and a pair of twins, the progression to a third birth depends very much on whether the twins came first or second. We also discover that at parities beyond 3, twinning rates increase with parity, especially at very short durations since the previous birth.vital events

Childbearing patterns for Swedish mothers of twins, 1961-1999

The Nordic population registers provide a unique possibility to study the demographic behavior of very small population groups and rare events. In this paper, we study the childbearing behavior of Swedish mothers of twins between 1961 and 1999, inclusive. Our most consistent finding is that mothers of twins wait noticeably longer than women with singletons before they have another child. This apart, mothers with twins at their first birth have next-birth fertility patterns very similar to women who have two singletons at their first two births. This commonality in child-bearing behavior does not extend to higher-order births. For mothers with a singleton and a pair of twins, the progression to a third birth depends very much on whether the twins came first or second. Beside these main results our fascinating material also provides a number of descriptive findings. The Swedish twinning rate has increased since the mid-1970s in response to a growing use of fertility-stimulating treatments such as in-vitro fertilization, in parallel with similar developments in many other countries. Such medical procedures are applied mainly to women beyond prime childbearing ages. Nevertheless, we find no simple age pattern in twinning rates. Even in recent years they do not just in-crease with the woman’s age. By way of contrast, at parities beyond 3 twinning rates increase with parity when we control for calendar period, time since last previous birth, and (NB) the woman’s own age.Sweden, twin studies

Genetic variation in competition traits at different ages and time periods and correlations with traits at field tests of 4-year-old Swedish Warmblood horses

For many years, the breeding value estimation for Swedish riding horses has been based on results from Riding Horse Quality Tests (RHQTs) of 4-year-olds only. Traits tested are conformation, gaits and jumping ability. An integrated index including competition results is under development to both get as reliable proofs as possible and increases the credibility of the indexes among breeders, trainers and riders. The objectives of this study were to investigate the suitability of competition data for use in genetic evaluations of horses and to examine how well young horse performance agrees with performance later in life. Competition results in dressage and show jumping for almost 40 000 horses from the beginning of the 1960s until 2006 were available. For RHQT data of 14 000 horses judged between 1988 and 2007 were used. Genetic parameters were estimated for accumulated competition results defined for different age groups (4 to 6 years of age, 4 to 9 years of age and lifetime), and for different birth year groups. Genetic correlations were estimated between results at RHQT and competitions with a multi-trait animal model. Heritabilities were higher for show jumping than dressage and increased with increasing age of the horse and amount of information. For dressage, heritabilities increased from 0.11 for the youngest group to 0.16 for lifetime results. For show jumping corresponding values increased from 0.24 to 0.28. Genetic correlations between competition results for the different age groups were highly positive (0.84 to 1.00), as were those between jumping traits at RHQT and competition results in show jumping (0.87 to 0.89). For dressage-related traits as 4-year-old and dressage competition results the estimated genetic correlations were between 0.47 and 0.77. We suggest that lifetime results from competitions should be integrated into the genetic evaluation system. However, genetic parameters showed that traits had changed during the over 35-year period covered due to the development of the sport, which needs to be considered in future genetic evaluations

Inrush Current Management During Medium Voltage Microgrid Black Start with Battery Energy Storage System

This paper addresses the black start of medium voltage distribution networks (MV-DNs) by a battery energy storage system (BESS). The BESS consists of a two-level voltage source inverter interfacing MV-DN which has limited overcurrent capability. On the other hand, MV-DN normally includes several step-up and step-down transformers that are drawing sympathetic inrush current in energizing stage. Therefore, the major difficulty to perform black start by BESS during MV-DN island operation lies in the fact that the inverter has to simultaneous control the network voltage and its output current. This paper presents two control approaches for a BESS in order to control the inrush current during MV-DN black start. The proposed control schemes consist of droop, voltage and current loops in the stationary reference frame. The droop loop is used to generate the voltage reference. An intermediate voltage and inner current loops are designed for output voltage regulation, current reference generation as well as current tracking, respectively. New reference modifiers are included into droop and voltage loops to limit inrush current. The proposed control schemes are experimentally tested for energizing Ingå MV-DN in Finland by 1 MVA BESS, and their performance is compared in terms of inrush current value and voltage quality. The obtained results prove that both methods are able to feed the load with a fixed voltage in the steady-state as well as to limit the transformer inrush current considering the inverter overcurrent limit.© 2022 authors. Published by IEEE. This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see https://creativecommons.org/licenses/by/4.0/fi=vertaisarvioitu|en=peerReviewed

Ei sanat salahan joua : fennistiikan murteenkeruun historiaa 1868–1925

Pro gradu -tutkielmani käsittelee Suomen murteiden sanakirjan taustaksi kerätyn Suomen murteiden sana-arkiston kartuttamisen historiaa; fennistisen murteenkeruun alkuvaiheita. Lähestyn murresanakirjan pitkää hanketta tutkimus- ja kulttuurihistoriallisesta näkökulmasta. Kansankielen sanakirja on fennistiikan merkittävimpiä tutkimushankkeita. Suo-men kielen vanhojen pitäjänmurteiden sanasto on ällistyttävän laaja aineisto, jonka keräämiseen ja julkaisemiseen on kulunut toista vuosisataa, ja sanakirjan toimitustyö jatkuu edelleen. Kansanmurteemme sisältävät paitsi kielitieteellisesti mielenkiintoista aineistoa myöskin runsaasti tietoa agraarisen elinkeinorakenteen aikakaudelta. Dialektologia ja kansatiede kulkevat käsikkäin. Murresanakirja on niin ollen merkittävä kansallinen omaisuus, jonka arvo koko suomalaiselle yhteiskunnalle on eittämättä suuri. Murteiden sanakirjan syntysanat on ajoitettavissa vuoteen 1868, vaikka toki fennistiikassa oli leksikografisia pyrintöjä jo ennen sitä (mm. Lönnrotin Suomalais-ruotsalainen sanakirja). Sanakirjahankkeessa on hahmotettavissa kolme vaihetta, joita kutsun ryhdistäytymisiksi. Nämä tapahtuivat noin vuosina 1896, 1916 ja 1925. Valotan työni aluksi hieman kansallisten tieteiden ja 1800-luvun alun aatehistoriallista taustaa (luku 2), jonka jälkeen tutkin murresanakirjahankkeen alkuvaiheita ja ensimmäisten sanastonkeruiden käynnistymistä (luku 3). Käsittelen kutakin hankkeen organisatorista muutosvaihetta ja hallinnollisten puitteiden kehittymistä luvuissa 4-6. Lopuksi pohdin murresanakirjan ja murteenkeruun historiallista merkitystä fennistiikalle ja yhteiskunnalle (luku 7). Tutkimukseni lähteinä on oppihistoriallista kirjallisuutta sekä murteiden keruusta vastanneiden yhteisöjen asiakirjoja. Erityisen kiinnostaviksi osoittautuivat Kotimaisten kielten tutkimuskeskuksessa säilytettävät sanakirjahankkeen hallinnolliset asiakirjat 1916-1925. Tuon esiin varhaisempiakin pöytäkirjamainintoja. Hankkeen alussa Suomalaisen Kirjallisuuden Seuran Kielitieteellinen Osakunta ja Kotikielen Seura keräsivät ensimmäisiä sanastokokoelmia. Tämän jälkeen ensimmäinen ryhdistäytyminen tapahtui vuodesta 1896 lähtien, jolloin Suomalaisen Kirjallisuuden Seura otti vastuun hankkeesta, E. N. Setälän tunnettua sanakirjaohjelmaa ja E. A. Ekmanin Suomen kielen keräilysanastoa noudattaen. Keruu oli kuitenkin liian hidasta, joten 1916 perustettiin Suomen kielen sanakirjaosakeyhtiö, jotta toimintaan saataisiin enemmän varoja. Ensimmäinen maailmansota ja sisällissota kuitenkin romahduttivat rahan arvon, ja kolmannen kerran hanke jouduttiin organisoimaan uudelleen vuonna 1925, Sanakirjasäätiön muodossa. Vuonna 1976 Sanakirjasäätiö liittyi Kotimaisten kielten tutkimuskeskukseen. Kansanmurteiden keräämisessä korostuu kaikissa keruun vaiheissa kaksi asiaa. Ensinnäkin sanastuksella oli aina kiire. Vanhat murteet olivat katoamassa, ja ne piti saada nopeasti talteen. Tähän kiinnitettiin huomiota jo varhain, ja vielä 1900-luvun loppupuoliskollakin, kun keruuhanke hiljalleen saatiin loppuunviedyksi. Toiseksi sanakirjahanke on aina joutunut elämään kädestä suuhun, toisin sanoen taloudelliset puitteet ovat sanelleet keruumahdollisuudet. Vakaalle taloudelliselle pohjalle hanke pääsi vasta 1930-luvulla Sanakirjasäätiön aikana, jolloin siihen alettiin saada valtion rahoitusta. Murresanakirjahankkeen läpi kulkee punaisena lankana kansallisromanttinen innostus ja isänmaallis-tieteellinen pyrkimys suomen kirjakielen kehittämiseen, joka vielä 1800-luvun puolivälissä oli meneillään. Kansalliset tieteet lujittivat itsenäistymistä ja suoma-laistumista. Aatehistorian kautta sanakirjahanke asettuu laajempaan yhteyteen

On the Variability of the Temperature Coefficients of mc-Si Solar Cells with Irradiance

The temperature sensitivity of silicon solar cells is in general assumed to be constant with irradiance in PV forecasting models, although it has been demonstrated experimentally that this is not true. In this study a theoretical model is established that describes the variation of the temperature coefficients of a silicon solar cell as a function of the irradiance. It is shown that the temperature sensitivity of the solar cell efficiency is decreasing with the irradiance and that the main reason for this behavior comes from the increase of the open-circuit voltage with light intensity. Moreover, a dependency of the cell's ideality factor on the irradiance has to be assumed to receive good modelling results that can be confirmed experimentally

Temperature coefficients of compensated silicon solar cells - influence of ingot position and blend-in-ratio

Published version of an article in the journal: Energy Procedia. Also available on Science Direct: http://dx.doi.org/10.1016/j.egypro.2015.07.004Solar-grade silicon made from a metallurgical route presents boron and phosphorus compensation. Earlier work has shown that cells made from such material produce more energy than reference polysilicon modules when the temperature and irradiance is high. In the present study, solar cells from two different ingots with different blend-in-ratios were made from wafers at varying ingot heights in order to investigate how the temperature coefficients vary with compensation level and ingot height. The results suggest that solar modules made with solar cells from different ingot heights will perform differently at high temperature. It was also observed that the compensation level seems to have a smaller impact on the temperature coefficients than the ingot height

Koagulationsfaktor XIII – inte bara ett kongenitalt blödningsproblem

Factor XIII (FXIII) cross-links fibrin monomers to strengthen clots. The congenital severe autosomal type of FXIII deficiency wit

Design and Development of OECT Logic Circuits for Electrical Stimulation Applications

This paper presents the first successful implementation of fully printed electronics for flexible and wearable smart multi-pad stimulation electrodes intended for use in medical, sports and lifestyle applications. The smart multi-pad electrodes with the electronic circuits based on organic electrochemical transistor (OECT)-based electronic circuits comprising the 3–8 decoder for active pad selection and high current throughput transistors for switching were produced by multi-layer screen printing. Devices with different architectures of switching transistors were tested in relevant conditions for electrical stimulation applications. An automated testbed with a configurable stimulation source and an adjustable human model equivalent circuit was developed for this purpose. Three of the proposed architectures successfully routed electrical currents of up to 15 mA at an output voltage of 30 V, while one was reliably performing even at 40 V. The presented results demonstrate feasibility of the concept in a range of conditions relevant to several applications of electrical stimulation.This research is part of the WEARPLEX project, funded by the European Commission’s Horizon 2020 research program under grant agreement number 825339

Sustainable breeding strategies for the Red Maasai sheep

How could we conserve Red Maasai sheep and increase productivity for better livelihood for livestock keepers