Creation and dynamics of two-dimensional skyrmions in antiferromagnetic spin-1 Bose-Einstein condensates

We numerically simulate the creation process of two-dimensional skyrmionic excitations in antiferromagnetic spin-1 Bose--Einstein condensates by solving the full three-dimensional dynamics of the system from the Gross--Pitaevskii equation. Our simulations reproduce quantitatively the experimental results of [Choi et al., Phys. Rev. Lett. 108, 035301 (2012)] without any fitting parameters. Furthermore, we examine the stability of the skyrmion by computing the temporal evolution of the condensate in a harmonic potential. The presence of both the quadratic Zeeman effect and dissipation in the simulations is vital for reproducing the experimentally observed decay time.Comment: 6 pages, 7 figure

Quantum knots in Bose-Einstein condensates created by counterdiabatic control

We theoretically study the creation of knot structures in the polar phase of spin-1 BECs using the counterdiabatic protocol in an unusual fashion. We provide an analytic solution to the evolution of the external magnetic field that is used to imprint the knots. As confirmed by our simulations using the full three-dimensional spin-1 Gross-Pitaevskii equation, our method allows for the precise control of the Hopf charge as well as the creation time of the knots. The knots with Hopf charge exceeding unity display multiple nested Hopf links.Comment: 7 pages, 6 figure

Experimental realization of a Dirac monopole through the decay of an isolated monopole

We experimentally observe the decay dynamics of deterministically created isolated monopoles in spin-1 Bose-Einstein condensates. As the condensate undergoes a change between magnetic phases, the isolated monopole gradually evolves into a spin configuration hosting a Dirac monopole in its synthetic magnetic field. We characterize in detail the Dirac monopole by measuring the particle densities of the spin states projected along different quantization axes. Importantly, we observe the spontaneous emergence of nodal lines in the condensate density that accompany the Dirac monopole. We also demonstrate that the monopole decay accelerates in weaker magnetic field gradients.Comment: 10 pages, 7 figure

Musiikki autismikirjon lapsen tukena varhaiskasvatuksessa

Tiivistelmä. Niin varhaiskasvatuksen kentällä kuin mediassa saattaa kohdata autismikirjon henkilöitä, joille musiikki on yksi ilmaisun keino tai suuri mielenkiinnon kohde. Kandidaatintutkielmamme käsittelee autismikirjon lasta ja musiikin tukikeinoja varhaiskasvatuksessa. Tutkielman avulla tuomme esille autismikirjon lapsen vahvuuksia sekä haasteita käyttäytymisen, vuorovaikutuksen ja kommunikaation näkökulmista. Näiden samojen osa-alueiden valossa kartoitamme musiikillisia tukikeinoja varhaiskasvatuksen piirissä. Valtakunnallisen varhaiskasvatussuunnitelman perusteissa oppimisen alueisiin kuuluva musiikki on osa monipuolista pedagogista toimintaa, johon jokaisella lapsella on oikeus. Autismikirjo on neurobiologinen kehityshäiriö ja se vaikuttaa laaja-alaisesti lapsen älylliseen, sosiaaliseen sekä toiminnalliseen kehitykseen. Autismikirjo toimii yläkäsitteenä monille oireyhtymille. Tuella pyritään helpottamaan autismikirjon henkilön kehityspolkua. Tärkeää on nähdä jokainen henkilö omana yksilönä vahvuuksineen ja haasteineen. Tutkielmassamme näemme tärkeänä opettajan roolin tuen tarjoajana. Tutkimusmenetelmämme on kuvaileva, integroiva kirjallisuuskatsaus, joka mahdollistaa lähdekirjallisuuden monipuolisen tarkastelun. Olemme käyttäneet tutkielmassamme kotimaista sekä kansainvälistä lähdekirjallisuutta. Kirjallisuuden ja tutkimusten perusteella merkittävinä tekijöinä nähdään varhaiskasvatuksen opettajan mahdollistamat musiikilliset elämykset sekä vuorovaikutukselliset tilanteet autismikirjon lapsille. Erilaisilla musiikillisilla keinoilla voidaan tukea vuorovaikutustaitoja ja kommunikointikykyä

Self-reported health problems and obesity predict sickness absence during a 12-month follow-up : a prospective cohort study in 21 608 employees from different industries

Objectives To study whether self-reported health problems predict sickness absence (SA) from work in employees from different industries. Methods The results of a health risk appraisal (HRA) were combined with archival data of SA of 21 608 employees (59% female, 56% clerical). Exposure variables were self-reported health problems, labelled as ' work disability (WD) risk factors' in the HRA, presence of problems with occupational well-being and obesity. Age, socioeconomic grading and the number of SA days 12 months before the survey were treated as confounders. The outcome measure was accumulated SA days during 12-month follow-up. Data were analysed separately for males and females. A Hurdle model with negative binomial response was used to analyse zero-inflated count data of SA. Results The HRA results predicted the number of accumulated SA days during the 12-month follow-up, regardless of occupational group and gender. The ratio of means of SA days varied between 2.7 and 4.0 among those with ' WD risk factors' and the reference category with no findings, depending on gender and occupational group. The lower limit of the 95% CI was at the lowest 2.0. In the Hurdle model, ' WD risk factors', SA days prior to the HRA and obesity were additive predictors for SA and/or the accumulated SA days in all occupational groups. Conclusion Self-reported health problems and obesity predict a higher total count of SA days in an additive fashion. These findings have implications for both management and the healthcare system in the prevention of WD. © Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.Peer reviewe

Myeloperoxidase Associates With Degenerative Remodeling and Rupture of the Saccular Intracranial Aneurysm Wall

Rupture of a saccular intracranial aneurysm (sIA) is often fatal. Thus, early detection of rupture-prone sIAs is vital. Myeloperoxidase (MPO), derived mainly from neutrophils, associates with sIA rupture, and therefore its role in sIA pathogenesis warrants further studies. We analyzed MPO and its association with other histological markers in 36 (16 unruptured and 20 ruptured) sIA samples by immunohistochemistry. MPO was present in all studied sIAs, and its expression associated with wall inflammatory cell infiltrations (r = 0.50, 0.63, and 0.75, all p <0.002), degenerative remodeling (p = 0.002) and rupture (p = 0.003). MPO associated strongly with the presence of organized luminal thrombi (p <0.001), which also stained positive for MPO. Polymorphonuclear MPO+ cells were detected in the sIA walls, indicating neutrophils as MPO-source. MPO correlated strongly with accumulation of oxidized lipids (r = 0.67, p <0.001) and loss of smooth muscle cells (r = -0.68, p <0.001), suggesting that MPO is a relevant source of oxidative stress leading to cell death in the sIA wall. Furthermore, MPO associated with erythrocyte fragmentation (r = 0.74, p <0.001) and iron deposition (p = 0.041), 2 outcomes known to amplify MPO-dependent oxidative stress. Taken together, these results suggest that MPO associates with degenerative remodeling predisposing to sIA wall rupture and may serve as a biomarker of a rupture-prone sIA wall.Peer reviewe

Neuregulin signaling pathway in smoking behavior

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Data mining applied to linkage disequilibrium mapping

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Could continuous cover forestry be an economically and environmentally feasible management option on drained boreal peatlands?

Environmental and economic performance of forestry on drained peatlands was reviewed to consider whether continuous cover forestry (CCF) could be a feasible alternative to even-aged management (EM). CCF was regarded feasible particularly because continuously maintaining a tree stand with significant transpiration and interception capacity would decrease the need for ditch network maintenance. Managing CCF forests in such a way that the ground water levels are lower than in clear-cut EM forests but higher than in mature EM forests could decrease greenhouse gas emissions and negative water quality impacts caused both by anoxic redox reactions and oxidation and mineralization of deep peat layers. Regeneration studies indicated potential for satisfactory natural regeneration under CCF on drained peatlands. An economic advantage in CCF over EM is that fewer investments are needed to establish the forest stand and sustain its growth. Thus, even if the growth of trees in CCF forests were lower than in EM forests, CCF could at least in some peatland sites turn out to be a more profitable forest management regime. An advantage of CCF from the viewpoint of socially optimal forest management is that it plausibly reduces the negative externalities of management compared to EM. We propose that future research in drained peatland forests should focus on assessing the economic and environmental feasibility of CCF.Peer reviewe