| 1. |
- Alenius Dahlqvist, Jenny, et al.
(författare)
-
Heart rate variability in children with fontan circulation : lateral tunnel and extracardiac conduit
- 2012
-
Ingår i: Pediatric Cardiology. - New York : Springer-Verlag New York. - 0172-0643 .- 1432-1971. ; 33:2, s. 307-315
-
Tidskriftsartikel (refereegranskat)abstract
- The technique in Fontan surgery has developed from the lateral tunnel (LT) toward the extracardiac conduit (EC) used to reduce long-term complications such as atrial arrhythmia and sinus node dysfunction. Heart rate variability (HRV) examines cardiac nervous activity controlling the sinus node. This study aimed to investigate HRV in a cohort of children with univentricular hearts, focusing on the relation between HRV and surgical procedure. For 112 children with Fontan circulation, HRV was analyzed using power spectral analysis. Spectral power was determined in three regions: very-low-frequency (VLF), low-frequency (LF), and high-frequency (HF) regions. Patients were compared with 66 healthy controls subject. Patients with LT were compared with patients who had EC. The children with Fontan circulation showed a significantly reduced HRV including total power (P < 0.0001), VLF (P < 0.0001), LF (P < 0.0001), and HF (P = 0.001) compared with the control subjects. The LT and EC patients did not differ significantly. Reduced HRV was found in both the LT and EC patients. In terms of HRV reduction, EC was not superior to LT.
|
|
| 2. |
- Bengtsson, G. J, et al.
(författare)
-
Determination of Radiative Lifetimes In Neutral Arsenic Using Time-resolved Laser Spectroscopy In the Vuv Region
- 1992
-
Ingår i: Astronomy & Astrophysics. - 0004-6361. ; 263:1-2, s. 440-442
-
Tidskriftsartikel (refereegranskat)abstract
- Inspired by the recent Hubble Space Telescope first observations of arsenic in an astrophysical object we have determined the natural radiative lifetime of the upper states of two of the three resonance lines of As I. Short pulse laser excitation at 193.7 and 197.2 nm was achieved using different non-linear optical mixing schemes. Using time-resolved spectroscopy we obtain tau(4p(2)5s P-4(3/2))=4.3(5) ns and T(4p(2)5s P-4(1/2)=4.5(5)ns yielding the absorption oscillator strengths f(abs)(193.7 nm) =0.123 (17) and f(abs)(1 97.2 nm)=0.059(8).
|
|
| 3. |
- Bengtsson, G. J, et al.
(författare)
-
Determination of Radiative Lifetimes In Neutral Nitrogen Using Short Laser-pulses From A Distributed Feedback Dye-laser
- 1991
-
Ingår i: Zeitschrift für Physik D Atoms, Molecules and Clusters. - 0178-7683. ; 22:1, s. 397-399
-
Tidskriftsartikel (refereegranskat)abstract
- Radiative lifetimes were determined for two short-lived states in neutral nitrogen. Following photodissociation and two-photon excitation employing the same UV source, excitation to higher states was performed with a distributed feedback dye laser (DFDL). The lifetimes were found to be tau(2p2 4d4D7/2) = 17(3) ns and tau(2p2 5s4P5/2) = 22(3) ns.
|
|
| 4. |
- Bengtsson, G. J, et al.
(författare)
-
Natural Lifetimes of Excited-states of Neutral Nitrogen Determined By Time-resolved Laser Spectroscopy
- 1992
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 45:5, s. 2712-2715
-
Tidskriftsartikel (refereegranskat)abstract
- Radiative lifetimes were determined for three quartet states of neutral nitrogen, and sequences of Rydberg states were studied using depletion spectroscopy. Free nitrogen atoms were generated by photodissociation of N2O using frequency-tripled dye-laser radiation that was two-photon resonant with the 2p(2)3p 4S or 4D states. Further quartet states were reached by a subsequent single-photon absorption. We obtain tau(2p(2)3p 4D7/2) = 44(2) ns, tau(2p(2)3p 4S3/2) = 26.0(1.5) ns, and tau(2p(2)6s4P5/2) = 41(7) ns.
|
|
| 5. |
- Bengtsson, G. J, et al.
(författare)
-
Oscillator-strengths For Resonance Transitions In Neutral Selenium and Tellurium Derived From Time-resolved Laser Spectroscopy
- 1992
-
Ingår i: Zeitschrift für Physik D Atoms, Molecules and Clusters. - 0178-7683. ; 23:1, s. 29-32
-
Tidskriftsartikel (refereegranskat)abstract
- We have measured radiative lifetimes for selenium and tellurium resonance levels by using short pulse laser excitation in differentially heated resonance cells. We obtained tau(3S1 Se I) = 2.9(5) ns and tau(3S1 Te I) = 3.1(5) ns, which together with branching ratio values given by Ubelis and Berzinsh yield the absorption oscillator strength f(abs)(Se I, 196.0 nm) = 0.074(16) and f(abs)(Te I, 214.3 nm) = 0.098(17).
|
|
| 6. |
- Bengtsson, G. J, et al.
(författare)
-
Radiative-lifetime and Lande-factor Measurements of the Se-i 4p(3)5s (5)s(2) Level Using Pulsed Laser Spectroscopy
- 1992
-
Ingår i: Journal de Physique II. - : EDP Sciences. - 1155-4312 .- 1286-4870. ; 2:4, s. 773-779
-
Tidskriftsartikel (refereegranskat)abstract
- First laser spectroscopic investigations on atomic selenium are reported. Natural selenium was thermally dissociated in a quartz resonance cell keeping the background pressure of abundant selenium molecules low by differential heating. The 4p35s5S2 level was excited by frequency-tripled pulsed-dye laser radiation at 207 nm. From time-resolved recordings of the fluorescence decay at 216 nm a natural radiative lifetime of 493(15) ns was determined, while quantum-beat and optical double-resonance measurements in an external magnetic field yielded g(J) = 2.0004(10) for the Lande factor. The results are compared with previous theoretical and experimental data.
|
|
| 7. |
- Bengtsson, G. J, et al.
(författare)
-
Time-resolved Spectroscopic Studies of the 7p 2p States of Neutral Silver Following Vuv Excitation
- 1991
-
Ingår i: Zeitschrift für Physik D Atoms, Molecules and Clusters. - 0178-7683. ; 22:1, s. 437-439
-
Tidskriftsartikel (refereegranskat)abstract
- The radiative lifetimes of the 7 p2P3/2, 1/2 states of silver and the hyperfine structure of the 7 p2P3/2 state have been measured using pulsed laser excitation and direct observation of the induced fluorescence light decay. In order to excite this doublet, VUV radiation at 185 nm was applied, as generated by frequency tripling and anti-Stokes Raman shifting of the output of a Nd: YAG laser pumped dye laser. The lifetimes were found to be tau = 255(20) ns and tau = 285(25) ns for the J = 3/2 state and J = 1/2 state, respectively. The hyperfine structure of the 7 p2P3/2 state was measured by the quantum beat method. The magnetic dipole interaction constant for the Ag-107 isotope was found to be a = - 4.5(2) MHZ.
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
|
|
