"Meidän oma Yrjö" : Eemil Nestor Setälä ja Yrjö Wichmann yhteistyökumppaneina

E. N. Setälä ja Yrjö Wichmann työskentelivät kollegoina sekä Helsingin Yliopistossa että useissa tieteellisissä seuroissa suomen ja sen sukukielten tutkimuksen arvostettuina edustajina. Varsinkin uransa alkutaipaleella he olivat perheystäviä ja yhteistyökumppaneita, kuitenkin niin, että Setälällä oli aina selvä johtoasema. Sen suomin valtuuksin hän ohjasi ja määräsi Wichmannia ja muitakin nuorempia kollegoitaan omasta näkökulmastaan tarkoituksenmukaisiin työtehtäviin ja luottamustoimiin, jotka saattoivat olla hyvinkin työläitä ja pitkäkestoisia. Artikkelissa ei kuvata Setälän ja Wichmannin tieteellisen tutkimustyön sisältöjä eikä sen tuloksia. Sen sijaan käsitellään heidän tieteenalansa yleistä tilannetta ja kuvataan heidän työskentelyään tieteellisinä kollegoina 1800-luvun lopun ja 1900-luvun ensimmäisten vuosikymmenten aikana. Artikkeli perustuu esitelmään, joka pidettiin Suomalais-Ugrilaisen Seuran järjestämässä Yrjö Wichmann -seminaarissa Helsingissä 19.10.2018.</p

Matias Aleksanteri Castrén ja Kalevalan ruotsinnos

Kun Elias Lönnrotin kokoama runoeepos, ns. Vanha Kalevala, ilmestyi vuonna 1835, se käänsi suomen kielen ja suomalaisen kulttuurin arvostuksen huimaan nousuun. Kalevala innosti myös maisteriopintojaan viimeistelevää, alkuaan pappisuralle aikonutta Matias Aleksanteri Castrénia suuntaamaan huomionsa suomen ja sen sukukielten tutkimukseen. Koska alkuperäistä Kalevalaa pystyivät lukemaan vain muutamat harvat oppineiston edustajat, Suomalaisen Kirjallisuuden Seura julisti kilpailun runomuotoisen ruotsin- tai saksankielisen käännöksen aikaansaamiseksi. Tällaisia ei kuitenkaan ilmaantunut. Helsingin yliopiston suomen kielen lehtori Carl Niclas Keckman luennoi Kalevalasta ja laati siitä sanatarkan ruotsinnoksen, mutta ei runomittaista versiota. Muutaman vuoden odotuksen jälkeen Kalevalasta jo aiemmin kiinnostunut Castrén ryhtyi kääntämään eeposta. Suomalaisen Kirjallisuuden Seuran stipendiaattina hän keräsi kesällä 1839 taustatietoa ja uutta kansanperinneaineistoa Vienan Karjalassa. Aktiivinen kääntäminen kesti noin kaksi vuotta. Käännöstyön ohella Castrén julkaisi dosentinväitöskirjan ja joitakin pienempiä tieteellisiä tutkimuksia. Kevätlukukaudella 1841 Castrén luennoi Helsingin yliopistossa Kalevalasta ja viimeisteli käännöstään. Se ilmestyi kesäkuussa 1841 ja sai hyvän vastaanoton. Esimerkiksi historiallis-vertailevan kielentutkimuksen kärkiedustajiin kuulunut Jacob Grimm perehtyi Kalevalaan ja luennoi siitä Berliinin tiedeakatemiassa Castrénin ruotsinnoksen perusteella. Castrénin ruotsinnos avasi uusia mahdollisuuksia Kalevalaa koskevalle tieteelliselle keskustelulle, koska eepos oli nyt aiempaa merkittävästi laajempien piirien luettavissa. Tärkeä rooli tässä keskustelussa oli itse Castrénilla ja hänen Kalevala-tulkinnoillaan. Kalevalan käännöksen myötä Castrén sai pysyvän kansainvälisen maineen arvostettuna kansanperinteen ja mytologian asiantuntijana. Kirjoitus perustuu Suomalais-Ugrilaisessa Seurassa 15.2.2019 pidettyyn esitelmään.] </li

Electronic-structure-induced deformations of liquid metal clusters

Ab initio molecular dynamics is used to study deformations of sodium clusters at temperatures $500\cdots 1100$ K. Open-shell Na$_{14}$ cluster has two shape isomers, prolate and oblate, in the liquid state. The deformation is stabilized by opening a gap at the Fermi level. The closed-shell Na$_8$ remains magic also at the liquid state.Comment: REVTex, 11 pages, no figures, figures (2) available upon request (e-mail to hakkinen at jyfl.jyu.fi), submitted to Phys. Rev.

Energy relaxation in graphene and its measurement with supercurrent

We study inelastic energy relaxation in graphene for low energies to find out how electrons scatter with acoustic phonons and other electrons. By coupling the graphene to superconductors, we create a strong dependence of the measured signal, i.e.,\ critical Josephson current, on the electron population on different energy states. Since the relative population of high- and low-energy states is determined by the inelastic scattering processes, the critical current becomes an effective probe for their strength. We argue that the electron-electron interaction is the dominant relaxation method and, in our model of two-dimensional electron-electron scattering, we find a scattering time $\tau_{e-e}=5... 13$ ps at T=500 mK, 1-2 orders of magnitude smaller than predicted by theory.Comment: 10 pages, 13 figures submitted to Physical Review

Stability of conductance oscillations in monatomic sodium wires

We study the stability of conductance oscillations in monatomic sodium wires with respect to structural variations. The geometry, the electronic structure and the electronic potential of sodium wires suspended between two sodium electrodes are obtained from self-consistent density functional theory calculations. The conductance is calculated within the framework of the Landauer-B\"utttiker formalism, using the mode-matching technique as formulated recently in a real-space finite-difference scheme [Phys. Rev. B \textbf{70}, 195402 (2004)]. We find a regular even-odd conductance oscillation as a function of the wire length, where wires comprising an odd number of atoms have a conductance close to the quantum unit $G_0=e^2/\pi\hbar$, and even-numbered wires have a lower conductance. The conductance of odd-numbered wires is stable with respect to geometry changes in the wire or in the contacts between the wire and the electrodes; the conductance of even-numbered wires is more sensitive. Geometry changes affect the spacing and widths of the wire resonances. In the case of odd-numbered wires the transmission is on-resonance, and hardly affected by the resonance shapes, whereas for even-numbered wires the transmission is off-resonance and sensitive to the resonance shapes. Predicting the amplitude of the conductance oscillation requires a first-principles calculation based upon a realistic structure of the wire and the leads. A simple tight-binding model is introduced to clarify these results.Comment: 16 pages, 20 figure

Effect of neck strength training on health-related quality of life in females with chronic neck pain: a randomized controlled 1-year follow-up study

Abstract Background Chronic neck pain is a common condition associated not only with a decrease in neck muscle strength, but also with decrease in health-related quality of life (HRQoL). While neck strength training has been shown to be effective in improving neck muscle strength and reducing neck pain, HRQoL among patients with neck pain has been reported as an outcome in only two short-term exercise intervention studies. Thus, reports on the influence of a long-term neck strength training intervention on HRQoL among patients with chronic neck pain have been lacking. This study reports the effect of one-year neck strength training on HRQoL in females with chronic neck pain. Methods One hundred eighty female office workers, 25 to 53 years of age, with chronic neck pain were randomized to a strength training group (STG, n = 60), endurance training group (ETG, n = 60) or control group (CG, n = 60). The STG performed high-intensity isometric neck strengthening exercises with an elastic band while the ETG performed lighter dynamic neck muscle training. The CG received a single session of guidance on stretching exercises. HRQoL was assessed using the generic 15D questionnaire at baseline and after 12 months. Statistical comparisons among the groups were performed using bootstrap-type analysis of covariance (ANCOVA) with baseline values as covariates. Effect sizes were calculated using the Cohen method for paired samples. Results Training led to statistically significant improvement in the 15D total scores for both training groups, whereas no changes occurred for the control group (P = 0.012, between groups). The STG improved significantly in five of 15 dimensions, while the ETG improved significantly in two dimensions. Effect size (and 95% confidence intervals) for the 15D total score was 0.39 (0.13 to 0.72) for the STG, 0.37 (0.08 to 0.67) for the ETG, and -0.06 (-0.25 to 0.15) for the CG. Conclusions One year of either strength or endurance training seemed to moderately enhance the HRQoL. Neck and upper body training can be recommended to improve HRQoL of females with neck pain if they are motivated for long-term regular exercise. Trial Registration ClinicalTrials.gov NCT01057836peerReviewe

Broken Symmetry in Density-Functional Theory: Analysis and Cure

We present a detailed analysis of the broken-symmetry mean-field solutions using a four-electron rectangular quantum dot as a model system. Comparisons of the density-functional theory predictions with the exact ones show that the symmetry breaking results from the single-configuration wave function used in the mean-field approach. As a general cure we present a scheme that systematically incorporates several configurations into the density-functional theory and restores the symmetry. This cure is easily applicable to any density-functional approach.Comment: 4 pages, 4 figures, submitted to PR

Structure and Magnetism of Neutral and Anionic Palladium Clusters

The properties of neutral and anionic Pd_N clusters were investigated with spin-density-functional calculations. The ground state structures are three-dimensional for N>3 and they are magnetic with a spin-triplet for 2<=N<=7 and a spin nonet for N=13 neutral clusters. Structural- and spin-isomers were determined and an anomalous increase of the magnetic moment with temperature is predicted for a Pd_7 ensemble. Vertical electron detachment and ionization energies were calculated and the former agree well with measured values for anionic Pd_N clusters.Comment: 5 pages, 3 figures, fig. 2 in color, accepted to Phys. Rev. Lett. (2001

Close-Packing of Clusters: Application to Al_100

The lowest energy configurations of close-packed clusters up to N=110 atoms with stacking faults are studied using the Monte Carlo method with Metropolis algorithm. Two types of contact interactions, a pair-potential and a many-atom interaction, are used. Enhanced stability is shown for N=12, 26, 38, 50, 59, 61, 68, 75, 79, 86, 100 and 102, of which only the sizes 38, 75, 79, 86, and 102 are pure FCC clusters, the others having stacking faults. A connection between the model potential and density functional calculations is studied in the case of Al_100. The density functional calculations are consistent with the experimental fact that there exist epitaxially grown FCC clusters starting from relatively small cluster sizes. Calculations also show that several other close-packed motifs existwith comparable total energies.Comment: 9 pages, 7 figure