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Introduction: Obstructive sleep apnea (OSA) has been associated with an elevated rate of cardiovascular mortality. However, this issue has not been investigated in patients with elevated proneness to cardiovascular diseases. Our hypothesis was that OSA would have an especially adverse effect on the risk of cardiovascular mortality in Finnish individuals exhibiting elevated proneness for coronary heart diseases. Methods: Ambulatory polygraphic recordings from 405 men having suspected OSA were retrospectively analyzed. The patients were categorized regarding sleep disordered breathing into a normal group (apnea hypopnea index (AHI) < 5, n = 104), mild OSA group ( 5 ≤ AHI < 15, n = 100), and moderate to severe OSA group (AHI ≥ 15, n = 201). In addition, basic anthropometric and health data were collected. In patients who died during the follow-up period (at least 12 years and 10 months), the primary and secondary causes of death were recorded. Results: After adjustment for age, BMI, and smoking, the patients with moderate to severe OSA suffered significantly ( p < 0.05) higher mortality (hazard ratio 3.13) than their counterparts with normal recordings. The overall mortality in the moderate to severe OSA group was 26.4 %, while in the normal group it was 9.7 %. Hazard ratio for cardiovascular mortality was 4.04 in the moderate to severe OSA and 1.87 in the mild OSA group. Conclusions: OSA seems to have an especially adverse effect on the cardiovascular mortality of patients with an elevated genetic susceptibility to coronary heart diseases. When considering that all our patients had possibility of continuous positive airway pressure treatment and our reference group consisted of patients suffering from daytime somnolence, the hazard ratio of 4.04 for cardiovascular mortality in patients with moderate to severe disease is disturbingly high. [ABSTRACT FROM AUTHOR]

In-beam gamma-ray and conversion electron spectroscopic studies have been performed on the 253 No nucleus. A strongly coupled rotational band has been identified and the improved statistics allows an assignment of the band structure as built on the $\ensuremath 9/2^-[734]_{\nu}$ ground state. The results agree with previously known transition energies but disagree with the tentative structural assignments made in earlier work. [ABSTRACT FROM AUTHOR]

A long-standing prediction of nuclear models is the emergence of a region of long-lived, or even stable, superheavy elements beyond the actinides. These nuclei owe their enhanced stability to closed shells in the structure of both protons and neutrons. However, theoretical approaches to date do not yield consistent predictions of the precise limits of the ‘island of stability’; experimental studies are therefore crucial. The bulk of experimental effort so far has been focused on the direct creation of superheavy elements in heavy ion fusion reactions, leading to the production of elements up to proton number Z = 118 (refs 4, 5). Recently, it has become possible to make detailed spectroscopic studies of nuclei beyond fermium (Z = 100), with the aim of understanding the underlying single-particle structure of superheavy elements. Here we report such a study of the nobelium isotope 254No, with 102 protons and 152 neutrons—the heaviest nucleus studied in this manner to date. We find three excited structures, two of which are isomeric (metastable). One of these structures is firmly assigned to a two-proton excitation. These states are highly significant as their location is sensitive to single-particle levels above the gap in shell energies predicted at Z = 114, and thus provide a microscopic benchmark for nuclear models of the superheavy elements. [ABSTRACT FROM AUTHOR]

An in-beam study of the transfermium nucleus 252No has been performed using the JUROSPHERE II array of germanium detectors coupled to the gas-filled recoil separator RITU. A new technique of recoil-fission tagging was used to extract tagged γ-ray data. Having significant spontaneous fission and α-decay branches, 252No is an ideal candidate for a comparative study. In a similar manner to α-decay tagging the fission events can be used to obtain γ-ray data. The recoil-fission tagged γ-ray spectrum showed a similar structure to the α-decay tagged γ-ray spectrum. By comparing the α-tagged and fission-tagged spectra and decay curves, it was shown that the spontaneous fission originates from the same initial state as the α decay. This extension of the tagging method allows in-beam spectroscopic data to be obtained from heavy nuclei with significant spontaneous-fission branches. [ABSTRACT FROM AUTHOR]

Evidence for the decay of non-yrast states in 254No has been observed for the first time in an experiment performed at the University of Jyväskylä. The experiment employed the JUROGAM array of germanium detectors coupled to the gas-filled recoil separator RITU and the focal-plane spectrometer GREAT. The ground-state rotational band has been tentatively extended up to a spin of 24ℏ and has a smoothly behaving dynamical moment of inertia. It is speculated that the observation of high-energy γ-rays is due to the decay of a K = 3 band-head state. [ABSTRACT FROM AUTHOR]

Over the past few years a great deal of new spectroscopic data has been obtained for transfermium nuclei. Recoil separators, coupled with modern target position and focal-plane spectrometers, allow detailed studies of the structure and decay properties of transfermium nuclei to be peformed. In-beam studies using the recoil-gating and recoil-decay tagging techniques mainly provide information on yrast states, whilst complementary focal-plane decay studies give access to non-yrast and isomeric structures. In-beam studies of nuclei in this region have largely been performed at ANL and JYFL, and decay experiments at GSI, JYFL, GANIL and ANL. The present contribution is focussed on recent developments and experiments carried out by a number of collaborating institutes at JYFL. [ABSTRACT FROM AUTHOR]

In recent years (1996-2001) the recoil-decay tagging technique has been employed with great success at the Department of Physics of the University of Jyväskylä. Various arrays of germanium detectors have been coupled to the RITU gas-filled separator in order to study nuclei far from stability. An overview of the physics studied with these arrays, along with discussion of technical development of the RITU separator, is presented. Even with a comparatively modest array of germanium detectors it has been possible to study nuclei produced with cross-sections as low as 200 nb. [ABSTRACT FROM AUTHOR]

: Gamma rays from excited states of 190Po have been observed using the Jurosphere Ge-detector array coupled to the RITU gas-filled separator. They were associated with a collective band which from spin 4&plank; onwards resembles the prolate rotational bands known in the isotones 188Pb and 186Hg. This indicates that in 190Po the prolate configuration becomes yrast above I = 2&plank;. The experimental results are interpreted in a two-band mixing calculation and are in agreement with α-decay data and potential energy surface calculations. [ABSTRACT FROM AUTHOR]

The low-energy nuclear structure and decay properties of the neutron-deficient isotopes195At and191Bi have been studied.195At was produced in the reaction142Nd(56Fe,p2n)195At and191Bi as the daughter activity of195At. The activities were implanted in a position-sensitive silicon detector after being separated from the primary beam by a gas-filled recoil separator. The 1/2+ intruder state was determined to be the ground state in195At with an alpha-decay energy of Eα = 6953(3) keV and a half-life T1/2 = 328(20) ms. Another state with an alpha-decay energy Eα = 7075(4) keV and a half-life T1/2 = 147(5) ms was found to decay to a 148.7(5) keV excited state in191Bi for which a spin and parity of 7/2- were deduced. Consequently, the same 7/2- character was assigned to the initial state at 32(7) keV in195At on the basis of unhindered alpha-decay. The 9/2- state, being the ground state in heavier odd-mass astatine isotopes, was not observed. [ABSTRACT FROM AUTHOR]

In-beam conversion electron spectroscopy experiments have been performed on the transfermium nuclei 253, 254No using the conversion electron spectrometer SACRED in nearly collinear geometry in conjunction with the gas-filled separator RITU at the University of Jyväskylä. The experimental setup is discussed and the spectra are compared to Monte Carlo simulations. The implications for the ground-state configuration of 253No are discussed. [ABSTRACT FROM AUTHOR]

Excited states of the Z = 102 nuclide 254No have been studied in the reaction 208Pb(48Ca,2n) by means of in-beam γ -ray spectroscopy in combination with recoil gating and recoil decay tagging. A Ge detector array, consisting of four clover detectors, and a gas-filled separator were used. Six γ-ray lines were observed and associated with E2 transitions in the ground state band of 254No, the highest-lying of these being the 16+→ 14+ transition. Based on global systematics and the extrapolated 2+ 1 excitation energy, the value β2= 0.27 ± 0.03 was extracted for the quadrupole deformation. An improved value for the half-life of 254No, T1/2= (48 ± 3) s, was determined. [ABSTRACT FROM AUTHOR]

A framework for including shadowing effects to quark and gluon production in very high energy nucleus-nucleus collisions is given. A formalism for impact parameter dependent nuclear structure functions of partons is introduced and, using two models to describe the average shadowing corrections to the parton number densities, the average numbers and the transverse energy spectrum of hard partons produced in U+U collisions at RHIC and LHC energies are computed. We conclude that shadowing and also the impact parameter dependence of structure functions should be taken into account at very high energies. [ABSTRACT FROM AUTHOR]

The time development of the fields associated with a straight cosmic string in the local U(1) model is studied numerically in an expanding universe. The effective potential is time dependent due to the cooling of the universe. After the spontaneous breaking of the U(1) symmetry the fields start to oscillate as the system tends towards the static state of the stable Nielsen-Olesen string. It is shown that energy flows out of the comoving cylinder in the form of electromagnetic waves. Due to Hubble damping and energy outflow the oscillation amplitudes decrease but static fields are not obtained without additional damping terms originating, e.g., from particle production. [ABSTRACT FROM AUTHOR]

We present a space-time formulation for the rescattering of hard partons produced in primary QCD subcollisions within a nucleus-nucleus collision. As an application we calculate the rescattering rate for dilepton production in 100 GeV/ A+100 GeV/ A uranium-uranium collisions. [ABSTRACT FROM AUTHOR]

Neutron-deficient isotopes of radium have been produced in the reactionsCl+Lu,Ar+Yb, andAr+Yb and separated in-flight with a gas-filled recoil separator. The activities have been identified on the basis of correlated alpha decay chains. The alpha particle energy E and the half-life T of an isomeric state of the new isotope,Ra, have been determined to be (7615±20) keV and (33) ms, respectively. An assignment of another decay with E = (7577±20) keV and T=(1.1) ms toRa is made on the basis of one observed three-decay chain. Tentative evidence for the production of the new isotopeRa is also given. The values E = (7860±60) keV and T=(0.7) ms were measured. Improved decay data have been obtained forRa. The results are E = (7484±10) keV and T=(59) ms. Earlier findings concerning the decay of two states inRa and an isomer inRa have been confirmed. Approximate values for cross sections have been determined forRa, produced using theAr+Yb reaction and forRa,Ra, andRa using theCl+Lu reaction. The results are 2 nb (Ra), 4 nb (Ra), 40 nb (Ra), and 800 nb (Ra). [ABSTRACT FROM AUTHOR]

Neutron-rich nuclidesRu andRu produced in symmetric fission ofU by 20 MeV protons have been studied at the IGISOL facility by means of β-ray, γ-ray and conversion electron spectroscopy. A total of 12 and 6 γ-transitions were observed in the decays ofRu andRu, respectively. Multipolarities were determined for a few transitions. The beta decay half-life was determined to be 11.6±0.6 s forRu and 1.75±0.07 s forRu. As a side product, a new value of 2.1±0.3 s for the β half-life of theRh 1 state was obtained. The decay energy measured with the plastic scintillator was 2.81 ±0.05 MeV forRu and 4.52 ±0.08 MeV forRu. The beta decay schemes ofRu andRu isotopes indicate that the main fraction of their beta strength resides in two 0→1 spin-flip transitions with their log f t values between 4.4 and 4.7. The decay energies and the energies of the 1 GT states are compared with the macroscopic-microscopic model calculations. The observed GT-strengths are discussed in the framework of the deformed single-particle model. [ABSTRACT FROM AUTHOR]

In this paper we wish to report the first direct observations of the beta decays ofPd and of a new isotopePd. The measured β-half-life is 4.3±0.3 s forPd. ForPd, the existence of two beta-decaying states with the same half-life but of opposite parity cannot be excluded. The measured half-life forPd is 0.92±0.13 s. The observed beta half-lifes are in good agreement with the QRPA predictions. The observed level structure ofAg andAg are discussed in the frame of the level systematics of the known odd Ag isotopes closer to stability. [ABSTRACT FROM AUTHOR]

PostacceleratedNi beams from the Munich tandem have been used to study the residual activities of the compound reactionsNi→Zr,Zr,Zr,Nb,Mo,Mo with the help of γ excitation functions, multi spectrum analyses of γ radiation, γγ coincidences and the measurement of the ratio EC/ gb. Beta decay schemes for the following new isotopes or isomers have been derived:Tb (6, 7) 4.5±0.5 sTb 1 1.5±1 sTb (11/2) 29 sTb 1 8±4 sDy 13.6±1 sDy 0 29±3 sHo (11/2) 5.8±0.4 sHo 1 2.2±1.1 sHo (2) 72±4 sEr 0 4.5±0.4 sEr 0 18.5±0.7 sTm J≧6 0.7±0.2 sTm (4, 5) 3.5±0.6 s The Q value for the β decay ofEr toHo has been measured to be 4,010±80 keV with respect to the 2 state inHo. [ABSTRACT FROM AUTHOR]

Alpha-decay properties of the isotope 191At were investigated for the first time and the decay properties of 193At and 195At were studied with improved accuracy. The nuclei were produced in fusion-evaporation reactions of 54Fe and 56Fe ions with 141Pr and 142Nd targets. The fusion products were separated in-flight using the gas-filled recoil separator RITU and implanted into a position-sensitive silicon detector. The isotopes were identified using position, time and energy correlations between the implants and subsequent alpha decays. New information concerning the low-lying states in the corresponding alpha-decay daughter nuclei 187Bi, 189Bi and 191Bi was also gained using alpha-gamma coincidences. [ABSTRACT FROM AUTHOR]

Neutron-deficient uranium isotopes were studied via α spectroscopic methods. A low-lying α-decaying isomeric state was found in 218U. The new isomeric state was assigned spin and parity Iπ=8+. The isomer decays by α emission with an energy E = 10678(17)keV and with a half-life T1/2 = (0.56+0.26-0.14)ms. The known alpha-decay properties of the ground state of 218U was measured with improved statistics. The ground-state α-decay has an energy E = 8612(9)keV and a half-life T1/2 = (0.51+0.17-0.10)ms. [ABSTRACT FROM AUTHOR]

Neutron-deficient α-decaying nuclei have been produced using fusion-evaporation reactions. A gas-filled recoil separator was used to separate the fusion products from the scattered beam. The activities were implanted in a position sensitive silicon detector. The isotopes were identified using spatial and time correlations between implants and decays. During ten years of operation time about twenty new α-decaying isotopes have been identified in the translead region. In addition numerous α-decay studies have been performed on already known isotopes yielding much improved precision for the measured decay properties. An overview of the α-decay studies performed for the translead nuclei employing the gas-filled recoil separator will be given. [ABSTRACT FROM AUTHOR]

Atiyah and Manton have shown how one can simply construct a Skyrmion-like configuration from an instanton. We generalise their ansatz to a thermal instanton and derive from it a thermal Skyrmion-like configuration. [ABSTRACT FROM AUTHOR]

Neutron deficient mercury isotopes were produced in the reaction 36Ar + 144Sm using bombarding energies of 180–230 MeV. Fusion products were separated in-flight from the primary beam using a gas-filled recoil separator. An alpha line with the alpha particle energy and half-life of (7069±11) keV and (2.1−0.7+1.8) ms, respectively, was assigned to the new mercury isotope 174Hg. [ABSTRACT FROM AUTHOR]

The new radon isotopeRn was produced in the reactionTm(Cl, 7n)Rn using bombarding energies from 5.6 to 6.1 MeV/nucleon. Fusion products were separated in-flight from the primary beam using a gas-filled recoil separator. The alpha particle energy and half-life ofRn were measured to be (7260±7) keV and (65) ms, respectively. Another new alpha line was assigned to an isomeric state inRn for which an alpha particle energy of (7356±7) keV and a half-life of (19) ms were obtained. [ABSTRACT FROM AUTHOR]

The francium isotopesFr were produced in the reactionCl+Yb using bombarding energies of 4.9-5.3 MeV/nucleon. Fusion products were separated in-flight from the primary beam using a gas-filled recoil separator. An alpha line with the alpha particle energy and half-life of (7468±9) keV and (19) ms, respectively, was assigned toFr. Previously reported decay properties ofFr were confirmed. [ABSTRACT FROM AUTHOR]

Two new neutron-deficient isotopesAc have been produced in fusion reactions with 5.2-5.6 MeV/nucleonAr ions onLu and identified on the basis of genetic correlations. The fusion evaporation products were separated on-line using a gas-filled magnetic recoil separator. The alpha energy and half-life ofAc were determined to be (7572±15) keV and (95) ms, respectively. A new alpha line with a half-life of (25) ms and an energy of (7758±20) keV is assigned to the decay of an isomeric state inAc. Another new activity with a half-life of (22) ms and an alpha energy of (7712±25) keV is assigned toAc. [ABSTRACT FROM AUTHOR]