From one-dimensional charge conserving superconductors to the gapless Haldane phase

We develop a framework to analyze one-dimensional topological superconductors with charge conservation. In particular, we consider models with $N$ flavors of fermions and $(\mathbb{Z}_2)^N$ symmetry, associated with the conservation of the fermionic parity of each flavor. For a single flavor, we recover the result that a distinct topological phase with exponentially localized zero modes does not exist due to absence of a gap to single particles in the bulk. For $N>1$, however, we show that the ends of the system can host low-energy, exponentially-localized modes. The analysis can readily be generalized to systems in other symmetry classes. To illustrate these ideas, we focus on lattice models with $SO\left(N\right)$ symmetric interactions, and study the phase transition between the trivial and the topological gapless phases using bosonization and a weak-coupling renormalization group analysis. As a concrete example, we study in detail the case of $N=3$. We show that in this case, the topologically non-trivial superconducting phase corresponds to a gapless analogue of the Haldane phase in spin-1 chains. In this phase, although the bulk is gapless to single particle excitations, the ends host spin-$1/2$ degrees of freedom which are exponentially localized and protected by the spin gap in the bulk. We obtain the full phase diagram of the model numerically, using density matrix renormalization group calculations. Within this model, we identify the self-dual line studied by Andrei and Destri [Nucl. Phys. B, 231(3), 445-480 (1984)], as a first-order transition line between the gapless Haldane phase and a trivial gapless phase. This allows us to identify the propagating spin-$1/2$ kinks in the Andrei-Destri model as the topological end-modes present at the domain walls between the two phases

Leikkauksen ihanuudesta ja kurjuudesta

Leikkaajan vastuulla on rakentaa elokuvan materiaaleista toimiva kokonaisuus, olipa elokuva ohjattu, näytelty tai kuvattu miten hyvin tai huonosti tahansa. Tämä vastuu on suuri ja joskus raskas kantaa, varsinkin kun työskentelee aloittelevana leikkaajana harjoituselokuvien parissa elokuvakoulussa, kun omat odotukset ja suorituspaineet ovat korkealla. Leikkaaminen on aikaa vievää ja kärsivällisyyttä vaativaa: elokuvan valmistuminen vaatii yleensä useita leikkauskierroksia. Kierrokset kirkastavat kerrontaa ja tislaavat elokuvan ajatusta esiin pikkuhiljaa. Leikkaaminen on katsojan kokemuksen muotoilua ja ennen kaikkea kommunikointia, tarinankerrontaa. Leikkaaminen on tasapainottelua katsojan roolin ja elokuvan kaikkien ongelmien ratkaisijan roolin välillä. Leikkausversiota katsellessa leikkaaja pyrkii reagoimaan näkemäänsä kuin ensikertalainen katsoja ja tarkkailee tunteitaan: miltä mikäkin elokuvan kohta tuntuu. Mikä toimii ja mikä ei, miksi? Tämän perusteella leikkaaja tietää, mitä kohtaa työstää ja kuinka. Leikkauksen toimivuuteen ei ole tarkkoja sääntöjä ja leikkaajat tekevätkin leikkauksellisia valintoja usein intuitionsa varassa. Intuitiivista leikkaamista leimaa sen helppous ja keveys. Intuitiivinen päätöksenteko tuntuu syntyvän ilman tietoista järkeilyä, vaikka sen taustalla lienee paljon tiedostamatonta tietoa ja kokemusta. Leikkaajan sokeutuminen on sitä, kun hän turtuu ja kyllästyy työstämänsä elokuvan materiaaleihin niin, että arvostelukyky elokuvan suhteen hämärtyy. Tämä johtuu ensinnäkin siitä, että leikkaaja on työstänyt elokuvaa kauan aikaa ja nähnyt sen lukuisia kertoja. Sokeutumista aiheuttaa myös leikkaajan uupuminen leikkausprosessissa. Leikkaajan on tärkeää osata palautua sokeutumisen tilasta esimerkiksi pitämällä taukoa leikkaamisesta. Leikkaajan työssä tärkeää on omien erityispiirteiden tunteminen ja arvostaminen, sekä leikkaajan työnkuvan ymmärtäminen. Keskeistä on myös luottamus muihin työryhmän jäseniin, jotta leikkaajan suorituspaineet olisivat mahdollisimman pienet. Tällöin keskeneräisen työn näyttäminen muille on helpompaa. Erityisesti ohjaajan ja leikkaajan välinen luottamus on tärkeää

Faster Transition to the Second Child in late 20th Century Finland: A Study of Birth Intervals

Birth intervals are known to influence child and parental health and wellbeing, yet studies on the recent development of birth intervals in contemporary developed societies are scarce. We used individual-level representative register data from Finland (N=26,120; 54% women) to study the first interbirth interval of singleton births in cohorts born in 1955, 1960, 1965, 1970, and 1975. In women, the average interbirth interval has shortened by 7.8 months and in men by 6.2 months between the cohorts of 1955 and 1975. A higher age at first birth was associated with shorter birth intervals (in women, b = -1.68, p<.001; in men, b = -1.77, p<.001 months per year). Educational level moderated the effect of age at first on the first birth interval in both sexes. Due to rising ages at first birth in developed societies and the manifold ramifications of shorter birth intervals, this topic deserves more scholarly attention and studies from other countries

Implicit attitudes and personnel selection : a phenomenological study regarding the implicit attitudes of personnel selectors'in relation to their work and job-applicants

The purpose of this study is to describe and understand how personnel recruiters reason when they select new co-workers to an organisation. A focus is on the implicit thoughts and characteristics the personnel recruiters ascribe to the job-applicant. Another aim is to generate new knowledge in relation to how personnel selection is done in real life. A phenomenological approach is proposed as a way to reach the personnel recruiters' subjective perceptions and feelings about their work. Eleven recruiters from companies and municipalities in Sweden answered two questions each regarding the interview process, of which ten protocols were analyzed. To achieve a better understanding of the meaning constitution and the specific thoughts recruiters have in employment situations we used the qualitative software MCA-Minerva. The results showed a tendency among the recruiters to characterise the applicants on the basis of their own earlier experiences and perceptions, implying that some of the participants manifest implicit attitudes that could, in specific situations, lead to implicit discrimination

Microbiological Surveillance of Biogas Plants: Targeting Acetogenic Community

Acetogens play a very important role in anaerobic digestion and are essential in ensuring process stability. Despite this, targeted studies of the acetogenic community in biogas processes remain limited. Some efforts have been made to identify and understand this community, but the lack of a reliable molecular analysis strategy makes the detection of acetogenic bacteria tedious. Recent studies suggest that screening of bacterial genetic material for formyltetrahydrofolate synthetase (FTHFS), a key marker enzyme in the Wood-Ljungdahl pathway, can give a strong indication of the presence of putative acetogens in biogas environments. In this study, we applied an acetogen-targeted analyses strategy developed previously by our research group for microbiological surveillance of commercial biogas plants. The surveillance comprised high-throughput sequencing of FTHFS gene amplicons and unsupervised data analysis with the AcetoScan pipeline. The results showed differences in the acetogenic community structure related to feed substrate and operating parameters. They also indicated that our surveillance method can be helpful in the detection of community changes before observed changes in physico-chemical profiles, and that frequent high-throughput surveillance can assist in management towards stable process operation, thus improving the economic viability of biogas plants. To our knowledge, this is the first study to apply a high-throughput microbiological surveillance approach to visualise the potential acetogenic population in commercial biogas digesters

The Company You Keep : Personality and Friendship Characteristics

Studies on personality and friendship have focused on similarities between friends, while differences in friendship patterns have received less attention. We used data from the British Household Panel Survey data (N = 12,098) to investigate how people's personalities are related to various characteristics of their three closest friends. All personality traits of the five-factor model were associated with several friendship characteristics with effect sizes corresponding to correlations between .06 and .09. Openness was especially prominent and idiosyncratic; individuals with high (vs. low) openness were about 3% more likely to have friends who live further away, are of the opposite sex and another ethnicity, and whom they meet less often. Agreeableness and extroversion were related to more traditional friendship ties. Individuals with high agreeableness had known their friends for a longer time, lived close to them, and had more "stay-at-homes" among their friends.Peer reviewe