Professori Lennart Simons ja Suomen ydinenergiateknologian alkuvaiheet

The establishment of the Energy Committee in 1955 is considered the starting point of Finland's nuclear history. The initiative was taken by the President of the Academy of Finland, A.I. Virtanen, who won the Nobel Prize in Chemistry in 1945, and Erkki Laurila, Professor of Technical Physics at the Helsinki University of Technology, was elected Chairman of the Committee. Almost everywhere in the world, nuclear physics experts led research into nuclear technology, while Finland's only nuclear physicist, Professor Lennart Simons of the University of Helsinki, did not participate at all in the work of the Energy Committee. However, he was a pioneer in basic nuclear physics research in Finland and played a major role in the introduction of medical applications of nuclear physics in Finland. The so-called Simons case, in which the University of Helsinki accused Simons of misconduct in his position and embezzlement of state funds, has been completely forgotten. The accusation led to Simons' suspension. He received a relatively light sentence for his offences. The case was ongoing at the time the Energy Committee was set up, and Mr Simons was not allowed to return to his post until more than six months after the Energy Committee was set up.Suomen atomihistorian lähtölaukauksena pidetään energiakomitean perustamista vuonna 1955. Aloitteen siihen teki Suomen Akatemian puheenjohtaja, kemian Nobelin palkinnon vuonna 1945 voittanut A.I. Virtanen, ja komitean puheenjohtajaksi valittiin Teknillisen Korkeakoulun teknillisen fysiikan professori Erkki Laurila. Lähes kaikkialla maailmassa atomitekniikan tutkimusta johtivat ydinfysiikan asiantuntijat, kun taas Suomen ainoa ydinfyysikko, Helsingin yliopiston professori Lennart Simons ei osallistunut lainkaan energiakomitean työhön. Hän oli kuitenkin suomalaisen ydinfysiikan perustutkimuksen pioneeri ja näytteli merkittävää osaa, kun ydinfysiikan lääketieteellisiä sovellutuksia alettiin ottaa Suomessa käyttöön. Kokonaan unohduksiin on jäänyt nk. Simonsin juttu, jossa Helsingin yliopisto syytti Simonsia väärinkäytöksistä virassaan ja valtion varojen kavaltamisesta. Syyte johti Simonsin viralta pidättämiseen. Hän sai varsin lievän tuomion rikkeistään. Oikeusjuttu oli käynnissä silloin, kun energiakomiteaa perustettiin, ja Simons sai palata virkaansa vasta yli puoli vuotta energiakomitean asettamisen jälkeen

Multiwalled carbon nanotubes as single electron transistors

Single electron transistors (SET) are fabricated from multiwalled carbon nanotubes (MWNT) by manipulation with an atomic force microscope. The devices consist of either a single MWNT with Au contacts at the ends or of two crossing tubes. In the latter device, the lower nanotube acted as the central island of a single electron transistor while the upper one functioned as a gate electrode. Coulomb blockade oscillations were observed on the nanotube at low temperatures. The voltage noise of the nanotube-SET was gain dependent as in conventional SETs. The charge sensitivity at 10 Hz was 6x10 exp -4 e/√Hz. Furthermore, in another device where the MWNT is suspended above the substrate between the electrodes, we measure an extremely high charge sensitivity of 6x 10 exp -6 e/√Hz at 45 Hz, comparable to the best of the conventional SETs.Peer reviewe

Polygenic prediction of educational attainment within and between families from genome-wide association analyses in 3 million individuals

Publisher Copyright: © 2022, The Author(s).We conduct a genome-wide association study (GWAS) of educational attainment (EA) in a sample of ~3 million individuals and identify 3,952 approximately uncorrelated genome-wide-significant single-nucleotide polymorphisms (SNPs). A genome-wide polygenic predictor, or polygenic index (PGI), explains 12–16% of EA variance and contributes to risk prediction for ten diseases. Direct effects (i.e., controlling for parental PGIs) explain roughly half the PGI’s magnitude of association with EA and other phenotypes. The correlation between mate-pair PGIs is far too large to be consistent with phenotypic assortment alone, implying additional assortment on PGI-associated factors. In an additional GWAS of dominance deviations from the additive model, we identify no genome-wide-significant SNPs, and a separate X-chromosome additive GWAS identifies 57.Peer reviewe

Polygenic prediction of educational attainment within and between families from genome-wide association analyses in 3 million individuals

We conduct a genome-wide association study (GWAS) of educational attainment (EA) in a sample of ~3 million individuals and identify 3,952 approximately uncorrelated genome-wide-significant single-nucleotide polymorphisms (SNPs). A genome-wide polygenic predictor, or polygenic index (PGI), explains 12-16% of EA variance and contributes to risk prediction for ten diseases. Direct effects (i.e., controlling for parental PGIs) explain roughly half the PGI's magnitude of association with EA and other phenotypes. The correlation between mate-pair PGIs is far too large to be consistent with phenotypic assortment alone, implying additional assortment on PGI-associated factors. In an additional GWAS of dominance deviations from the additive model, we identify no genome-wide-significant SNPs, and a separate X-chromosome additive GWAS identifies 57

Katsaus Suomen varhaiseen atomihistoriaan

Nykyisellä ydinteknologialla on lähinnä kaksi haaraa joita ovat ydinenergia ja lääketieteellinen isotooppitekniikka. Ensin mainitun lähtölaukauksena Suomessa pidetään nk. energiakomitean perustamista vuonna 1955. Tämän historian tutkimuksen painopiste on ollut 1960-ja 1970-luvun tapahtumissa, jotka liittyvät nykyisten ydinvoimalaitosten hankintakuvioihin. Professori Lennart Simons aloitti vakavasti otettavan ydinfysiikan tutkimuksen Suomessa ja oli alan ykkösnimi 1940- ja 1950-luvuilla kun koko länsimaailman yli pyyhkäisi atomiteknologian huuma, jota ehkä voi sanoa ensimmäiseksi teknologiahypeksi modernissa mielessä. Kirjan tarkoituksena on antaa lisävalaistusta suomalaisen ydinteknologian varhaiseen historiaan. Asiaa katsotaan luonnontieteen näkökulmasta, mutta esiin tuodaan myös se, miten aikakauden suuret poliittiset jännitteet vaikuttivat nousevan atomiteknologian kehitykseen Suomessa.The development of civilian nuclear technolog y began with full speed right after World War II, and has gone through an extremely shifting set of fortunes over the decades since then. The 1950’s were characterized by a huge public enthusiasm for the possibilities of atomic tech-nolog y, as there were unrealistic expectations that the new technolog y would lead to another industrial revolution. In the 1960’s the hype was replaced by realism, and the emergence of the anti-nuclear movement as a significant political force in the 1970’s made the progress of the nuclear power industry very cumbersome. In the early days of nuclear technolog y, it’s development was significantly connected to the general political climate. Particular examples can be seen in the careers of the communist nuclear physicist Frederic Joliot-Curie in France and the scientific leader of the Manhattan Project, Robert Oppenheimer in the USA.The current established history of atomic energ y in Finland sets the beginning to the initiative in 1955 of the Chairman of the Academy of Finland, the Nobel Prize awarded biochemist A.I. Virtanen, who recommended for the government the formation of the so called Energ y Committee. This committee worked under the chairmanship of the material physicist Erkki Laurila. It’s recommendations led to the purchase of an American research reactor and several other investments into research on atomic technolog y. Ten years later Finland decided on the purchase of its first commercial nuclear power stations. However, serious scientific activity in nuclear physics in Finland began after the successful research visit of the physicist Lennart Simons to the Niels Bohr Institute in 1938-1940, and his nomination to Professor of Physics at the University of Helsinki in 1941. Beginning in 1947, the research group of Simons constructed largely by their own effort a Van de Graaff-accelerator which was in active use until the 1980’s. Simons also took the initiative already in 1946 for embarking on the use of radioactive isotopes in medical diagnostics, which was the starting point for this field in Finland.Despite being the sole independent researcher in Finland of international significance in nuclear physics until the late 1950’s, Simons and his group had no part in the work of the Energ y Committee. Practically all developed nations had some atomic program in the 1950’s. Such an arrangement, where a government put aside its existing available expertise in nuclear physics, and instead relied on scientists from other fields, probably did not happen elsewhere. It is argued, that the basic explanation for this state of affairs can be sought in the political circumstances of the post-war years in Finland, and more precisely, in the fact that Lennart Simons clearly expressed his commitment to the progressive ideas and the peace movement of his time. The main focus of the book is on the period 1945 – 1960. Later developments are briefly discussed in light of the main events of this period.peerReviewe