Pairing instabilities in quasi-two-dimensional Fermi gases

We study non-equilibrium dynamics of ultracold two-component Fermi gases in low-dimensional geometries after the interactions are quenched from weakly interacting to strongly interacting regime. We develop a T-matrix formalism that takes into account the interplay between Pauli blocking and tight confinement in low-dimensional geometries. We employ our formalism to study the formation of molecules in quasi-two-dimensional Fermi gases near Feshbach resonance and show that the rate at which molecules form depends strongly on the transverse confinement. Furthermore, Pauli blocking gives rise to a sizable correction to the binding energy of molecules.Comment: 6 pages, 3 figure

Matemaattisten aineiden aineenopettajien täydennyskoulutustarpeet ja -toiveet sekä täydennyskoulutustarjonta

Tiivistelmä. Muuttuvassa maailmassa jatkuvan oppimisen merkitys korostuu, sillä ammattitaitovaatimukset päivittyvät maailman kehityksen mukana. Opettajan ammatissa jatkuva oppiminen tarkoittaa sitä, että opettajan tulee päivittää omaa osaamistaan vastaamaan tämän päivän osaamisvaatimuksia, jotta hän kykenee opettamaan oppilailleen tulevaisuuden taitoja. On tärkeää, että opettaja osaa tunnistaa tarpeen uuden oppimiselle ja kehittää omaa osaamistaan. Vaikka opettajan työ sisältää jatkuvan oppimisen, on mielenkiintoista tietää, kuinka halukkaita opettajat ovat päivittämään ja täydentämään omaa osaamistaan esimerkiksi täydennyskoulutuksilla tai opintojen täydentämisellä. Tutkielmassa selvitettiin, millainen tarve matemaattisten aineiden aineenopettajilla on opintojen täydentämiselle ja täydennyskoulutuksille sekä mitä he näiltä toivoivat. Tutkielmassa selvitettiin lisäksi, mitä opettajien tarpeiden ja toiveiden mukaisia koulutuksia on jo ennestään tarjolla. Tutkielmassa haluttiin myös verrata vasta valmistuvan ja kokeneen opettajan valmiuksia tietotekniikan opetuskäyttöön. Tutkimusta varten tehtiin kyselytutkimus Pohjois-Pohjanmaan, Kainuun sekä Lapin alueella toimiville matemaattisten aineiden aineenopettajille. Kyselytutkimukseen vastasi yhteensä 76 opettajaa ja heistä 28 opettajaa on mahdollisesti kiinnostuneita täydentämään opintojaan opetettavan aineen laajuisiksi. Pienemmän aihekokonaisuuden täydennyskoulutuksesta kiinnostuneita olivat 44 opettajaa. Tutkimuksessa selvisi, että vastanneilla opettajilla ei ole kovin suurta tarvetta fysiikan opintojen täydentämiselle, mutta fysiikkaan liittyvät täydennyskoulutukset heitä kuitenkin kiinnostavat. Tarjolla olevat täydennyskoulutukset liittyvät vahvasti matematiikan opettamiseen. Fysiikan aiheisiin ja opettamiseen liittyviä täydennyskoulutuksia on hyvin vähän tarjolla

Molecular mechanics force fields from ab initio calculations

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87595/2/224_1.pd

Splitting times of doubly quantized vortices in dilute Bose-Einstein condensates

Recently, the splitting of a topologically created doubly quantized vortex into two singly quantized vortices was experimentally investigated in dilute atomic cigar-shaped Bose-Einstein condensates [Y. Shin et al., Phys. Rev. Lett. 93, 160406 (2004)]. In particular, the dependency of the splitting time on the peak particle density was studied. We present results of theoretical simulations which closely mimic the experimental set-up. Contrary to previous theoretical studies, claiming that thermal excitations are the essential mechanism in initiating the splitting, we show that the combination of gravitational sag and time dependency of the trapping potential alone suffices to split the doubly quantized vortex in time scales which are in good agreement with the experiments. We also study the dynamics of the resulting singly quantized vortices which typically intertwine--especially, a peculiar vortex chain structure appears for certain parameter values.Comment: 5 pages, 5 figure

Effect of Inhaled Xenon on Cerebral White Matter Damage in Comatose Survivors of Out-of-Hospital Cardiac Arrest: A Randomized Clinical Trial

IMPORTANCE: Evidence from preclinical models indicates that xenon gas can prevent the development of cerebral damage after acute global hypoxic-ischemic brain injury but, thus far, these putative neuroprotective properties have not been reported in human studies. OBJECTIVE: To determine the effect of inhaled xenon on ischemic white matter damage assessed with magnetic resonance imaging (MRI). DESIGN, SETTING, AND PARTICIPANTS: A randomized single-blind phase 2 clinical drug trial conducted between August 2009 and March 2015 at 2 multipurpose intensive care units in Finland. One hundred ten comatose patients (aged 24-76 years) who had experienced out-of-hospital cardiac arrest were randomized. INTERVENTIONS: Patients were randomly assigned to receive either inhaled xenon combined with hypothermia (33°C) for 24 hours (n = 55 in the xenon group) or hypothermia treatment alone (n = 55 in the control group). MAIN OUTCOMES AND MEASURES: The primary end point was cerebral white matter damage as evaluated by fractional anisotropy from diffusion tensor MRI scheduled to be performed between 36 and 52 hours after cardiac arrest. Secondary end points included neurological outcome assessed using the modified Rankin Scale (score 0 [no symptoms] through 6 [death]) and mortality at 6 months. RESULTS: Among the 110 randomized patients (mean age, 61.5 years; 80 men [72.7%]), all completed the study. There were MRI data from 97 patients (88.2%) a median of 53 hours (interquartile range [IQR], 47-64 hours) after cardiac arrest. The mean global fractional anisotropy values were 0.433 (SD, 0.028) in the xenon group and 0.419 (SD, 0.033) in the control group. The age-, sex-, and site-adjusted mean global fractional anisotropy value was 3.8% higher (95% CI, 1.1%-6.4%) in the xenon group (adjusted mean difference, 0.016 [95% CI, 0.005-0.027], P = .006). At 6 months, 75 patients (68.2%) were alive. Secondary end points at 6 months did not reveal statistically significant differences between the groups. In ordinal analysis of the modified Rankin Scale, the median (IQR) value was 1 (1-6) in the xenon group and 1 (0-6) in the control group (median difference, 0 [95% CI, 0-0]; P = .68). The 6-month mortality rate was 27.3% (15/55) in the xenon group and 34.5% (19/55) in the control group (adjusted hazard ratio, 0.49 [95% CI, 0.23-1.01]; P = .053). CONCLUSIONS AND RELEVANCE: Among comatose survivors of out-of-hospital cardiac arrest, inhaled xenon combined with hypothermia compared with hypothermia alone resulted in less white matter damage as measured by fractional anisotropy of diffusion tensor MRI. However, there was no statistically significant difference in neurological outcomes or mortality at 6 months. These preliminary findings require further evaluation in an adequately powered clinical trial designed to assess clinical outcomes associated with inhaled xenon among survivors of out-of-hospital cardiac arrest. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00879892

Pulmonary manifestations and the effectiveness of enzyme replacement therapy in Fabry Disease with the p. Arg227Ter (p.R227*) mutation

Background: Fabry disease (FD) is caused by a defect in α-galactosidase A gene (GLA) which leads to a progressive accumulation of neutral shingolipids, mainly globotriaosylceramide and its metabolites in several organs. Pulmonary manifestations of FD mimic chronic obstructive pulmonary disease and are disproportionate to smoking status. The effect of enzyme replacement therapy (ERT) on pulmonary function is inconclusive. We studied the effect of ERT on pulmonary function in FD with a mutation p. Arg227Ter (p.R227*) which is one of the most common mutations causing classical FD in Finland and worldwide.Methods: Patients were annually examined by multidisciplinary team. Based on the maximal pulmonary oxygen consumption at the baseline, either cardiopulmonary exercise test or combination of spirometry and 6-minute walking test were performed annually during 5-year follow-up.Results: Four males and eight females met the criteria for ERT and were included in this study. Three of 12 patients had obstruction by GOLD criterion before ERT, and one had a borderline obstruction. In 5 years, five patients were classified as obstructive, although the real change in FEV1/FVC was unchanged in the whole cohort. Only one patient was an active smoker.Conclusion: In nonsmokers, pulmonary manifestations in classical FD are mild and might be stabilized by ERT.</p

Production of qqQQ final states in ee collisions in the left-right symmetric model

We consider the reaction ee ->qqQQ as a test of lepton number non-conservation in the framework of the left-right-symmetric electroweak model. The main contributions to this process are due to Majorana neutrino exchange in t-channel and doubly charged Higgs (Delta{--}) exchange in s-channel with a pair of right-handed weak bosons (WR) as intermediate state. We show that in a linear ee collider with the collision energy of 1 TeV (1.5 TeV) the cross section of this process is 0.01 fb (1 fb), and it will, for the anticipated luminosity of 10**{35} cm**{-2}, be detectable below the WR threshold. We study the sensitivity of the reaction on the masses of the heavy neutrino, WR and Delta{--}.Comment: 24 pages, 9 eps figures, uses axodraw.st

Incidence of Sudden Cardiac Death and Life-Threatening Arrhythmias in Clinically Manifest Cardiac Sarcoidosis With and Without Current Indications for an Implantable Cardioverter Defibrillator

Background: Cardiac sarcoidosis (CS) predisposes to sudden cardiac death (SCD). Guidelines for implantable cardioverter defibrillators (ICDs) in CS have been issued by the Heart Rhythm Society in 2014 and the American College of Cardiology/American Heart Association/Heart Rhythm Society consortium in 2017. How well they discriminate high from low risk remains unknown. Methods: We analyzed the data of 398 patients with CS detected in Finland from 1988 through 2017. All had clinical cardiac manifestations. Histological diagnosis was myocardial in 193 patients (definite CS) and extracardiac in 205 (probable CS). Patients with and without Class I or IIa ICD indications at presentation were identified, and subsequent occurrences of SCD (fatal or aborted) and sustained ventricular tachycardia were recorded, as were ICD indications emerging first on follow-up. Results: Over a median of 4.8 years, 41 patients (10.3%) had fatal (n=8) or aborted (n=33) SCD, and 98 (24.6%) experienced SCD or sustained ventricular tachycardia as the first event. By the Heart Rhythm Society guideline, Class I or IIa ICD indications were present in 339 patients (85%) and absent in 59 (15%), of whom 264 (78%) and 30 (51%), respectively, received an ICD. Cumulative 5-year incidence of SCD was 10.7% (95% CI, 7.4%-15.4%) in patients with ICD indications versus 4.8% (95% CI, 1.2%-19.1%) in those without (chi(2)=1.834, P=0.176). The corresponding rates of SCD were 13.8% (95% CI, 9.1%-21.0%) versus 6.3% (95% CI, 0.7%-54.0%; chi(2)=0.814, P=0.367) in definite CS and 7.6% (95% CI, 3.8%-15.1%) versus 3.3% (95% CI, 0.5%-22.9%; chi(2)=0.680, P=0.410) in probable CS. In multivariable regression analysis, SCD was predicted by definite histological diagnosis (P=0.033) but not by Class I or IIa ICD indications (P=0.210). In patients without ICD indications at presentation, 5-year incidence of SCD, sustained ventricular tachycardia, and emerging Class I or IIa indications was 53% (95% CI, 40%-71%). By the American College of Cardiology/American Heart Association/Heart Rhythm Society guideline, all patients with complete data (n=245) had Class I or IIa indications for ICD implantation. Conclusions: Current ICD guidelines fail to distinguish a truly low-risk group of patients with clinically manifest CS, the 5-year risk of SCD approaching 5% despite absent ICD indications. Further research is needed on prognostic factors, including the role of diagnostic histology. Meanwhile, all patients with CS presenting with clinical cardiac manifestations should be considered for an ICD implantation.Peer reviewe

Dientamoeba fragilis - the most common intestinal protozoan in the Helsinki Metropolitan Area, Finland, 2007 to 2017

Despite the global distribution of the intestinal protozoan Dientamoeba fragilis, its clinical picture remains unclear. This results from underdiagnosis: microscopic screening methods either lack sensitivity (wet preparation) or fail to reveal Dientamoeba (formalin-fixed sample). Aim: In a retrospective study setting, we characterised the clinical picture of dientamoebiasis and compared it with giardiasis. In addition, we evaluated an improved approach to formalin-fixed samples for suitability in Dientamoeba diagnostics. Methods: This study comprised four parts: (i) a descriptive part scrutinising rates of Dientamoeba findings; (ii) a methodological part analysing an approach to detect Dientamoebalike structures in formalin samples; (iii) a clinical part corn paring demographics and symptoms between patients with dientamoebiasis (n = 352) and giardiasis (n = 272), and (iv) a therapeutic part (n = 89 patients) investigating correlation between faecal eradication and clinical improvement. Results: The rate of Dientamoeba findings increased 20-fold after introducing criteria for Dientamoeba-like structures in formalin-fixed samples (88.9% sensitivity and 83.3% specificity). A further increase was seen after implementing faecal PCR. Compared with patients with giardiasis, the symptoms in the Dientamoeba group lasted longer and more often included abdominal pain, cramping, faecal urgency and loose rather than watery stools. Resolved symptoms correlated with successful faecal eradication (p<0.001). Conclusions: Previously underdiagnosed, Dientamoeba has become the most frequently recorded pathogenic enteroparasite in Finland. This presumably results from improved diagnostics with either PCR or detection of Dientamoeba-like structures in formalin-fixed samples, an approach applicable also in resource-poor settings. Symptoms of dientamoebiasis differ slightly from those of giardiasis; patients with distressing symptoms require treatment.Peer reviewe