| 1. |
- Aberg, Jonas, et al.
(författare)
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In vivo evaluation of an injectable premixed radiopaque calcium phosphate cement.
- 2011
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Ingår i: International journal of biomaterials. - : Hindawi Limited. - 1687-8795 .- 1687-8787. ; 2011
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Tidskriftsartikel (refereegranskat)abstract
- In this work a radiopaque premixed calcium phosphate cement (pCPC) has been developed and evaluated in vivo. Radiopacity was obtained by adding 0-40 % zirconia to the cement paste. The effects of zirconia on setting time, strength and radiopacity were evaluated. In the in vivo study a 2 by 3.5mm cylindrical defect in a rat vertebrae was filled with either the pCPC, PMMA or bone chips. Nano-SPECT CT analysis was used to monitor osteoblast activity during bone regeneration. The study showed that by adding zirconia to the cement the setting time becomes longer and the compressive strength is reduced. All materials evaluated in the in vivo study filled the bone defect and there was a strong osteoblast activity at the injury site. In spite of the osteoblast activity, PMMA blocked bone healing and the bone chips group showed minimal new bone formation. At 12 weeks the pCPC was partially resorbed and replaced by new bone with good bone ingrowth. The radiopaque pCPC may be considered to be used for minimal invasive treatment of vertebral fractures since it has good handling, radiopacity and allows healing of cancellous bone in parallel with the resorption of the cement.
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| 2. |
- Akre [Fall], Katja, 1971-, et al.
(författare)
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Risk for gastric cancer after antibiotic prophylaxis in patients undergoing hip replacement
- 2000
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Ingår i: Cancer Research. - Birmingham, USA : American Asoociation for Cancer Research. - 0008-5472 .- 1538-7445. ; 60, s. 6376-
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Tidskriftsartikel (refereegranskat)abstract
- Despite strong evidence of an association between Helicobacter pylori and gastric cancer, the benefit of eradicating H. pylori infection is unknown. Our aim was to test the hypothesis that exposure to high doses of antibiotics reduces risk for gastric cancer via possible eradication of H. pylori We conducted a nationwide case-control study nested in a cohort of 39,154 patients who underwent hip replacement surgery between 1965 and 1983. Such patients frequently receive prophylactic antibiotic treatment. During follow-up through 1989, we identified 189 incident cases of gastric cancer. For each case, three controls were selected from the cohort. Exposure data were abstracted from hospital records. Blood samples from a separate cohort undergoing hip replacement surgery were analyzed for anti-H. pylori IgG before and after surgery. Both long-term antibiotic treatment before surgery [odds ratio (OR), 0.3; 95% confidence interval (CI), 0.1-0.7] and prophylactic antibiotic treatment (OR, 0.7; 95% CI, 0.5-1.1) conferred a reduction in gastric cancer risk. The reduction appeared stronger after 5 years (OR, 0.6; 95% CI, 0.3-1.2) than during shorter follow-up after hip replacement (OR, 0.8; 95% CI, 0.4-1.7). There was an apparent decrease in risk with increasing body weight-adjusted doses of antibiotics (P = 0.13). However, the rate of H. pylori antibody disappearance was not strikingly higher in the cohort of patients undergoing hip replacement than in a control cohort. Our findings provide indirect support for the hypothesis that treatment with antibiotics at a relatively advanced age reduces the risk of gastric cancer.
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| 3. |
- Alenius Dahlqvist, Jenny, et al.
(författare)
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Heart rate variability in children with fontan circulation : lateral tunnel and extracardiac conduit
- 2012
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Ingår i: Pediatric Cardiology. - New York : Springer-Verlag New York. - 0172-0643 .- 1432-1971. ; 33:2, s. 307-315
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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.
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| 4. |
- Atturo, Francesca, et al.
(författare)
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The Human Cochlear Aqueduct and Accessory Canals : a Micro-CT Analysis Using a 3D Reconstruction Paradigm
- 2018
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Ingår i: Otology and Neurotology. - 1531-7129 .- 1537-4505. ; 39:6, s. e429-e435
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Tidskriftsartikel (refereegranskat)abstract
- Objective: We sought to study the anatomic variations of the cochlear aqueduct and its accessory canals in human temporal bones using micro-CT and a 3D reconstruction paradigm. More knowledge about the anatomic variations of these structures, particularly at the basal turn of the cochlea and round window niche, may be important to better preserve residual hearing as well as the neural supply during cochlear implant surgery.Methods: An archival collection of 30 human temporal bones underwent micro-CT and 3D reconstruction. A surface enhancement paradigm was applied. The application displays reconstructed slices as a 3D object with realistic 3D visualization of scanned objects. Virtual sectioning or cropping of the petrous bone presented subsequent areas. Thereby, the bony canals could be followed from inside the basal turn of cochlea and middle ear to the jugular foramen.Results: The cochlear aqueduct was always paralleled by an accessory canal containing the inferior cochlear vein. It ran from the basal turn of the cochlea and exited laterally in the jugular foramen. In 70% of the cases, a secondary accessory canal was observed and it derived mostly from a depression or infundibulum located in the floor of the round window niche. This canal also exited in the jugular foramen. The secondary accessory canal occasionally anastomosed with the primary accessory canal suggesting that it contains a vein that drains middle ear blood to the cranial sinus.Conclusion: Micro-CT with 3D surface reconstruction paradigm offers new possibilities to study the topographic anatomy of minor details in the human inner ear. The technique creates simulated transparent castings of the labyrinth with a coinciding surface view through enhancement of contrast between boundaries. Accessory canals that drain blood from the cochlea, spiral ganglion, and middle ear could be characterized three-dimensionally.
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| 5. |
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| 6. |
- Bajammal, Sohail S., et al.
(författare)
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The use of calcium phosphate bone cement in fracture treatment : A meta-analysis of randomized trials
- 2008
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Ingår i: Journal of Bone and Joint Surgery. American volume. - 0021-9355 .- 1535-1386. ; 90:6, s. 1186-96
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Available options to fill fracture voids include autogenous bone, allograft bone, and synthetic bone materials. The objective of this meta-analysis was to determine whether the use of calcium phosphate bone cement improves clinical and radiographic outcomes and reduces fracture complications as compared with conventional treatment (with or without autogenous bone graft) for the treatment of fractures of the appendicular skeleton in adult patients. METHODS: Multiple databases, online registers of randomized controlled trials, and the proceedings of the meetings of major national orthopaedic associations were searched. Published and unpublished randomized controlled trials were included, and data on methodological quality, population, intervention, and outcomes were abstracted in duplicate. Data were pooled across studies, and relative risks for categorical outcomes and weighted mean differences for continuous outcomes, weighted according to study sample size, were calculated. Heterogeneity across studies was determined, and sensitivity analyses were conducted. RESULTS: We identified eleven published and three unpublished randomized controlled trials. Of the fourteen studies, six involved distal radial fractures, two involved femoral neck fractures, two involved intertrochanteric femoral fractures, two involved tibial plateau fractures, one involved calcaneal fractures, and one involved multiple types of metaphyseal fractures. All of the studies evaluated the use of calcium phosphate cement for the treatment of metaphyseal fractures occurring primarily through trabecular, cancellous bone. Autogenous bone graft was used in the control group in three studies, and no graft material was used in the remaining studies. Patients managed with calcium phosphate had a significantly lower prevalence of loss of fracture reduction in comparison with patients managed with autograft (relative risk reduction, 68%; 95% confidence interval, 29% to 86%) and had less pain at the fracture site in comparison with controls managed with no graft (relative risk reduction, 56%; 95% confidence interval, 14% to 77%). We were unable to compare pain at the bone-graft donor site between the studies because of methodological reasons. Three studies independently demonstrated improved functional outcomes when the use of calcium phosphate was compared with the use of no grafting material. CONCLUSIONS: The use of calcium phosphate bone cement for the treatment of fractures in adult patients is associated with a lower prevalence of pain at the fracture site in comparison with the rate in controls (patients managed with no graft material). Loss of fracture reduction is also decreased in comparison with that in patients managed with autogenous bone graft.
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| 7. |
- Bengtsson, G. J, et al.
(författare)
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Determination of Radiative Lifetimes In Neutral Arsenic Using Time-resolved Laser Spectroscopy In the Vuv Region
- 1992
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Ingår i: Astronomy & Astrophysics. - 0004-6361. ; 263:1-2, s. 440-442
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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).
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| 8. |
- Bengtsson, G. J, et al.
(författare)
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Determination of Radiative Lifetimes In Neutral Nitrogen Using Short Laser-pulses From A Distributed Feedback Dye-laser
- 1991
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Ingår i: Zeitschrift für Physik D Atoms, Molecules and Clusters. - 0178-7683. ; 22:1, s. 397-399
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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.
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| 9. |
- Bengtsson, G. J, et al.
(författare)
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Natural Lifetimes of Excited-states of Neutral Nitrogen Determined By Time-resolved Laser Spectroscopy
- 1992
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Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 45:5, s. 2712-2715
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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.
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| 10. |
- Bengtsson, G. J, et al.
(författare)
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Oscillator-strengths For Resonance Transitions In Neutral Selenium and Tellurium Derived From Time-resolved Laser Spectroscopy
- 1992
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Ingår i: Zeitschrift für Physik D Atoms, Molecules and Clusters. - 0178-7683. ; 23:1, s. 29-32
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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).
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| 11. |
- Bengtsson, G. J, et al.
(författare)
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Radiative-lifetime and Lande-factor Measurements of the Se-i 4p(3)5s (5)s(2) Level Using Pulsed Laser Spectroscopy
- 1992
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Ingår i: Journal de Physique II. - : EDP Sciences. - 1155-4312 .- 1286-4870. ; 2:4, s. 773-779
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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.
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| 12. |
- Bengtsson, G. J, et al.
(författare)
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Time-resolved Spectroscopic Studies of the 7p 2p States of Neutral Silver Following Vuv Excitation
- 1991
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Ingår i: Zeitschrift für Physik D Atoms, Molecules and Clusters. - 0178-7683. ; 22:1, s. 437-439
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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.
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| 13. |
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| 14. |
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| 15. |
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| 16. |
- Bengtsson, Magnus, et al.
(författare)
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Fluorescence lidar imaging of fungal growth on high-voltage outdoor composite insulators
- 2005
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Ingår i: Optics and Lasers in Engineering. - : Elsevier BV. - 0143-8166 .- 1873-0302. ; 43:6, s. 624-632
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Tidskriftsartikel (refereegranskat)abstract
- Remote fluorescence imaging of fungal growth on polymeric high-voltage insulators was performed using a mobile lidar system with a laser wavelength of 355 nm. Insulator areas contaminated by fungal growth could be distinguished from clean surfaces and readily be imaged. The experiments were supported by detailed spectral studies performed in laboratory using a fibre-optic fluorosensor incorporating an optical multi-channel analyser system (OMA) and a nitrogen laser emitting radiation at 33 7 nm.
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| 17. |
- Bengtsson, Magnus, et al.
(författare)
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Fungus covered insulator materials studied with laser-induced fluorescence and principal component analysis
- 2005
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Ingår i: Applied Spectroscopy. - : SAGE Publications. - 0003-7028 .- 1943-3530. ; 59:8, s. 1037-1041
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Tidskriftsartikel (refereegranskat)abstract
- A method combining laser-induced fluorescence and principal component analysis to detect and discriminate between algal and fungal growth on insulator materials has been studied. Eight fungal cultures and four insulator materials have been analyzed. Multivariate classifications were utilized to characterize the insulator material, and fungal growth could readily be distinguished from a clean surface. The results of the principal component analyses make it possible to distinguish between algae infected, fungi infected, and clean silicone rubber materials. The experiments were performed in the laboratory using a fiber-optic fluorosensor that consisted of a nitrogen laser and an optical multi-channel analyzer system.
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| 18. |
- Bengtsson, Magnus, et al.
(författare)
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Remote laser-induced breakdown spectroscopy for the detection and removal of salt on metal and polymeric surfaces
- 2006
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Ingår i: Applied Spectroscopy. - : SAGE Publications. - 1943-3530 .- 0003-7028. ; 60:10, s. 1188-1191
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Tidskriftsartikel (refereegranskat)abstract
- The detection of contamination such as salt in outdoor high-voltage insulator systems and its subsequent removal are vital for a reliable transmission of electric power. Remote detection of salt on a copper metal surface was carried out by using a mobile laser-induced breakdown spectroscopy (LIBS) Lidar system with a laser wavelength of 355 nm. Detection of salt on a polymeric high-voltage insulator was obtained when an additional lens was inserted into the beam path, and the number of photons that was detected could be calculated by using a calibrated white light source. Ablative cleaning could readily be carried out with LIBS and was verified by observing the disappearance of the sodium D-line emission.
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| 19. |
- Bhandari, Mohit, et al.
(författare)
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Resolving controversies in hip fracture care : the need for large collaborative trials in hip fractures
- 2009
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Ingår i: Journal of Orthopaedic Trauma. - 0890-5339 .- 1531-2291. ; 23:6, s. 479-484
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Tidskriftsartikel (refereegranskat)abstract
- Hip fractures are a significant cause of morbidity and mortality worldwide and the burden of disability associated with hip fractures globally vindicate the need for high-quality research to advance the care of patients with hip fractures. Historically, large, multi-centre randomized controlled trials have been rare in the orthopaedic trauma literature. Similar to other medical specialties, orthopaedic research is currently undergoing a paradigm shift from single centre initiatives to larger collaborative groups. This is evident with the establishment of several collaborative groups in Canada, in the United States, and in Europe, which has proven that multi-centre trials can be extremely successful in orthopaedic trauma research.Despite ever increasing literature on the topic of his fractures, the optimal treatment of hip fractures remains unknown and controversial. To resolve this controversy large multi-national collaborative randomized controlled trials are required. In 2005, the International Hip Fracture Research Collaborative was officially established following funding from the Canadian Institute of Health Research International Opportunity Program with the mandate of resolving controversies in hip fracture management. This manuscript will describe the need, the information, the organization, and the accomplishments to date of the International Hip Fracture Research Collaborative.
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| 20. |
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| 21. |
- Borg, Tomas, 1963-, et al.
(författare)
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Development of a pelvic discomfort index to evaluate outcome following fixation for pelvic ring injury
- 2015
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Ingår i: Journal of Orthopaedic Surgery. - : Sage Publications. - 1022-5536 .- 2309-4990. ; 23:2, s. 146-149
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To develop a pelvic discomfort index (PDI) to evaluate outcome following fixation for pelvic ring injury.METHODS: 29 female and 44 male consecutive patients (mean age, 36 years) underwent internal fixation for pelvic ring injury of type B1 (n=10), B2 (n=22), B3 (n=15), C1 (n=18), C2 (n=5), and C3 (n=3), based on the AO/OTA classification. At postoperative 6, 12, and 24 months, patients were asked to assess their discomfort in the pelvis using a 14-item questionnaire. Three questions were open-ended, and responses were categorised by a single assessor. The remaining 11 questions were closed-ended and had 6 ordinal options from 'no discomfort' (score=0) to 'extremely severe discomfort' (score=5). The content validity and relevance of the 11 closed-ended questions was determined. The 14-item questionnaire was compared with the 36-item Short Form Health Survey (SF-36).RESULTS: Respectively at postoperative 6, 12, and 24 months, 78%, 71%, and 71% of the patients completed the 14-item questionnaire. Based on the factor analysis and responses to the open-ended questions, the number of items was reduced to 6 including pain, walking, mobility of the hips, loss of sensation in the legs, sexual life, and operation scar. Four factors could explain 96% of the total variance. The first factor involved the first 3 items (pain, walking, and hip motion) and addressed 'pelvis', whereas 3 factors involved the remaining items and each addressed peripheral neurology, sexual life, and operation scar. A PDI was developed using these 6 items. The PDI had high internal reliability (α=0.89), adequate content and criterion validity, and moderate correlation with the SF-36 total score or scores of physical function, bodily pain, and general health (r=0.50-0.77).CONCLUSION: The PDI provides valid, specific, and relevant information to assess outcome following fixation for pelvic ring injury.
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| 22. |
- Borg, Tomas, 1963-, et al.
(författare)
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Health-related quality of life and life satisfaction in patients following surgically treated pelvic ring fractures. A prospective observational study with two years follow-up
- 2010
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Ingår i: Injury. - : Elsevier. - 0020-1383 .- 1879-0267. ; 41:4, s. 400-404
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Pelvic ring fractures caused by high-energy trauma are severe injuries with well described radiological and clinical outcomes, whereas description from the patient's perspective is less well documented. The purpose of this study was to investigate patient-reported outcome following surgical treatment of pelvic fractures using quality of life instruments.METHODS: All 54 patients (28 male/26 female, ages 16-68) with pelvic fractures referred to our institution for surgical treatment 2003-2005 were prospectively included. The most common trauma was motor vehicle accident (44%). Additional injuries were seen in 74% and in 31% the ISS was >or=16. There were 31 B and 23 C type fractures. Patients were followed for two years using two validated questionnaires, SF-36 and LiSat-11, the latter an instrument consisting of 11 questions for evaluation of satisfaction with different aspects of life.RESULTS: 45 patients could be followed according to the study protocol for two years while 2 were untraceable and 1 died from unrelated causes. Of 6 nonresponders, 5 were unable due to psychiatric disorder. At two years pelvic fracture patients scored lower than the reference population in both physical and mental domains (SF-36). Highest mean score, 68, was in the domain Social Function (norm 89) while lowest mean score, 38, was in the domain Role Physical (norm 86). The mean score closest to the normative was for general health with 61 for patients and 78 for the normative group. In LiSat-11 pelvic fracture patients scored lower than the reference population in all areas. Satisfaction with life as a whole was 31% compared with 60% in the normative group.CONCLUSIONS: Two years after surgical treatment of pelvic ring fractures, patients reported substantially lower quality of life for both physical and mental domains, when compared with a reference population, even when radiological and clinical outcomes were considered favourable.
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| 23. |
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| 24. |
- Borg, Tomas
(författare)
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Pelvic Ring Injuries and Acetabular Fractures : Quality of Life Following Surgical Treatment
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim was to study outcome following surgery of the injured pelvis with focus on assessment from the patient’s perspective. All adult patients operatively treated for pelvic ring injuries or acetabular fractures at the Department of Orthopaedics, Uppsala University, starting 2003 were prospectively included and followed with quality of life (QoL) instruments for 2 years. The most common trauma mechanism was motor vehicle accident (MVA). Study I included 54 patients with pelvic ring injuries during the three-year period 2003-2005. The two instruments, SF-36 and LiSat-11, were used. In 45 responders lower than normative QoL and life satisfaction prevailed at two years after the injury. Study II included 12 patients with pelvic ring injuries or acetabular fractures sustained following a jump from height in an attempt to commit suicide. At four years all patients were still alive and SCID-interviews performed by a psychiatrist revealed low recurrence of self-destructive behaviour and high QoL in the younger patients. Study III included 136 patients with acetabular fractures where 52 had elementary and 84 associated fracture patterns. Fracture reduction was 0-1 mm in 106 patients and 2 mm or more in 30. QoL was significantly higher in patients with anatomically reduced fractures. Physical SF-36 domains improved with time, albeit QoL was lower than norm. Study IV had the aim to construct a condition-specific outcome instrument for patients with acetabular fractures. Closed and open questions were sent to 127 consecutive acetabular fracture patients at 6, 12 and 24 months following surgery. Responses were validated through factor analysis, scree tests, item reduction and principal component analysis which resulted in a multi-item verbal descriptive scale (VDS) with six condition-specific questions related to “Pain”, “Walking”, “Hip motion”, “Leg numbness”, “Sexual life”, “Operation scar” and a global question concerning impact on daily life activities for acetabular fracture assessment.
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| 25. |
- Borg, Tomas, et al.
(författare)
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Quality of Life After Operative Fixation of Displaced Acetabular Fractures
- 2012
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Ingår i: Journal of Orthopaedic Trauma. - : Lippincott Williams & Wilkins. - 0890-5339 .- 1531-2291. ; 26:8, s. 445-450
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The aim of this study was to determine quality of life (QoL) changes over time after internal fixation of acetabular fractures.Design: This pertains to a prospective cohort study, which was single centered.Setting: The study was conducted at the University Hospital.Patients: One hundred thirty-six patients (108 men, 28 women), age 17-83 years operated for an acetabular fracture during 2004-2008 were prospectively included and followed up for 2 years.Main Outcome Measures: QoL was evaluated via Short Form-36 (SF-36) and Life Satisfaction-11 at 6, 12, and 24 months. Radiographs were evaluated according to Matta at 2 years.Results: The most frequent fracture types were posterior wall (n31), associated anterior-posterior hemitransverse (n34), and associated both column (n29). One hundred twenty-nine patients could be assessed at 2 years, 4 did not respond, and 3 had died. The patients scored lower than norms in all 8 SF-36 domains with improvement over time for Physical Function (P < 0.0001) and Role Physical (P < 0.0001). The patients with postop reduction 0-1 mm scored better (P < 0.001-0.039) in 7 domains, all except vitality (P = 0.07), when compared with patients with residual displacement of >= 2 mm. Life satisfaction did not change with time and showed lower scores than normative in 9 of 11 items. Nineteen patients had undergone total hip replacement, and the strongest predictor was acetabular or femoral head impaction.Conclusions: QoL in surgically treated patients with displaced acetabular fracture keeps improving in physical SF-36 domains over a 2-year period although still lower than norms, and anatomical reduction results in better QoL outcome in most dimensions.
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| 26. |
- Borg, Tomas, et al.
(författare)
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Quality of life in patients operated for pelvic fractures caused by suicide attempt by jumping
- 2010
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Ingår i: Scandinavian Journal of Surgery. - : Sage Publications. - 1457-4969 .- 1799-7267. ; 99:3, s. 180-186
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Tidskriftsartikel (refereegranskat)abstract
- Background and Aims: Jumping from great height is an aggressive method of suicide attempt where the frequent combination of psychiatric disorder and somatic injuries makes treatment difficult. Our aim was to evaluate survival rate and get patient-reported outcome in patients operated for a pelvic or acetabular fracture sustained when jumping from a height as a suicide attempt. Patients and Methods: During the period 2003-2004, 12 patients (11 women) of whom eight were below 30 years of age, were prospectively included. At two years HRQoL (Health-Related Quality of Life) questionnaires (SF-36 and LiSat-11) were used to describe outcome, and at four years a structured psychiatric interview SCID-I (Structured Clinical Interview for DSM-IV Axis I Disorders) was done. Results: At four years all patients were alive. One patient had made a new suicide attempt. Eight patients gave adequate reply on SF-36 and LiSat-11 at two years. In all domains patients scored lower than a norm group with the relatively lowest values in physical domains. Younger patients assessed life as better when compared with middle aged patients. Conclusions: This study showed a very low recurrence rate into suicidal behaviour in a group of jumpers and all patients were alive at four years after a suicidal attempt by jumping. The high proportion of psychiatric disorder in these patients highlights the need for a combined treatment effort between orthopaedic and psychiatric expertise.
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| 27. |
- Borg, Tomas, et al.
(författare)
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Questionnaire to assess treatment outcomes of acetabular fractures
- 2012
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Ingår i: Journal of Orthopaedic Surgery. - : SAGE Publications. - 1022-5536 .- 2309-4990. ; 20:1, s. 55-60
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSETo construct a questionnaire to assess outcomes in patients who underwent internal fixation for acetabular fractures.METHODS27 female and 100 male consecutive patients (mean age, 50 years) who underwent internal fixation for acetabular fractures were included. Patients were asked to report their outcomes at months 6, 12, and 24 using a questionnaire. The initial questionnaire was constructed by an expert group. There were 11 closed questions, each came with 6 responses from ?no discomfort? to ?very severe discomfort?. Three open questions were added to cover topics that were not included. The content validity and relevance of the 11 closed questions was determined using factor analysis to determine the number of factors involved. Factorability of the correlation matrix was measured via the Bartlett test of sphericity and Kaiser-Meyer- Olkin (KMO) measure of sampling sufficiency. Factor loadings of <0.50 were considered acceptable for factor representation. Reliability in terms of internal consistency was expressed as Cronbach alpha coefficients. The responses to the 3 open questions were analysed and categorised by a single assessor.RESULTS120 (94%) of the patients completed at least one questionnaire, and 92 (72%) completed all 3 questionnaires during the follow-up period. Based on responses to the 6-month questionnaire, responses to the 11 closed questions were significantly intercorrelated (Spearman 0.17-0.80). After factor analysis and analysis of responses to open questions, the number of questions was reduced to 6 and included questions related to pain, walking, hip motion, leg numbness, sexual life, and operation scar. Reliability of the questionnaire was estimated to alpha=0.89. Criterion validity was adequate with a high correlation with the Short Form 36 (r=0.56-0.80).CONCLUSIONPatients treated with acetabular fractures can be adequately assessed using the 6-item questionnaire and one global question concerning impact on activities of daily living.
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| 28. |
- Brydegaard, Mikkel, et al.
(författare)
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Short-Wave infrared atmospheric scheimpflug lidar
- 2018
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Ingår i: EPJ Web of Conferences. - : EDP Sciences. ; 176
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Konferensbidrag (refereegranskat)abstract
- Atmospheric dual-band Scheimpflug lidar is demonstrated at 980 and 1550 nm. Signals are compared during three weather conditions, and the spatio-temporal resolution of the atmospheric structure is considered. The potential for aerosol classification is evaluated, and future directions are discussed.
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| 29. |
- Buciuto, Robert
(författare)
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Treatment of unstable trochanteric hip fractures : A clinical, mechanical and radiographic evaluation of the RAB-plate
- 2000
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The problems associated with the management of proximal femoral fractures gain more attention as the elderly population continue to increase. It has been estimated that the total number of hip fractures in the world will increase from 1.7 million per year in 1990 to 6.3 million per year in 2050 (Cooper et al 1992). Operative treatment of these fractures is a challenge for the orthopaedic surgeon mainly due to poor bone quality, which increases the risk of fixation failure.More than 50% of the total number of hip fractures are extracapsular fractures. Mortality, morbidity and costs as a result of trochanteric fracture are higher than those for a cervical fracture. The consequence is increased resource consumption in the national health-care system. The estimated total cost of treatment increase 3-fold in case of a complication. Therefore, a variety of different devices have been designed in order to decrease the ratio of complications. However, in spite of this, the reported ratio of fixation failure continues be high and may reach 25% following treatment of unstable trochanteric fractures. We evaluated a new type of fixation device, the RAB-plate (Rigidity Augmentation Baixauli), for the treatment of unstable trochanteric hip fractures. The RAB-plate is a fixed 120-degree angle blade-plate with a buttress rod.We performed three clinical trials where 391 unstable trochanteric fractures were stabilised with the RAB-plate or a Sliding Hip Screw (SHS). The results showed a statistically significant lower number of complications in fractures stabilised with the RAB-plate.The fatigue resistance of the RAB-plate was evaluated in a cyclic loading test model. The RAB-plate had a statistically significant higher fatigue strength than two different designs of the SHS.Stability of the fixation and modes of failure were radiographically analysed in a series of 218 unstable trochanteric fractures treated with the RAB-plate or the SHS. The RAB-plate provided a more stable fixation especially with regard to maintained postoperative alignment. However, positive predictors for fixation failure e.g.implant position within the femoral head, varus reduction in anteroposterior projection and screw/neck angle deviation in the lateral projection were identical for both devices.Spontaneous femoral neck fracture after removal of the fixation device in healed unstable trochanteric fractures was investigated in a series of 7 patients. Our results indicate that implant-induced osteoporosis (stress protection) is a possible cause of subsequent fracture.Our conclusions are that the RAB-plate is a safe implant for fixation of unstable trochanteric hip fractures and results in lower incidence of complications compared to SHS. Therefore, the RAB can be recommended for fixation of unstable trochanteric fractures.
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| 30. |
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| 31. |
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| 32. |
- Carlsson, Elin, et al.
(författare)
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In vitro and in vivo response to low-modulus PMMA-based bone cement
- 2015
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Ingår i: BioMed Research International. - : Hindawi Limited. - 2314-6133 .- 2314-6141.
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Tidskriftsartikel (refereegranskat)abstract
- The high stiffness of acrylic bone cements has been hypothesized to contribute to the increased number of fractures encountered after vertebroplasty, which has led to the development of low-modulus cements. However, there is no data available on the in vivo biocompatibility of any low-modulus cement. In this study, the in vitro cytotoxicity and in vivo biocompatibility of two types of low-modulus acrylic cements, one modified with castor oil and one with linoleic acid, were evaluated using human osteoblast-like cells and a rodent model, respectively. While the in vitro cytotoxicity appeared somewhat affected by the castor oil and linoleic acid additions, no difference could be found in the in vivo response to these cements in comparison to the base, commercially available cement, in terms of histology and flow cytometry analysis of the presence of immune cells. Furthermore, the in vivo radiopacity of the cements appeared unaltered. While these results are promising, the mechanical behavior of these cements in vivo remains to be investigated.
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| 33. |
- Christersson, Albert, et al.
(författare)
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Clinical outcome after plaster cast fixation for 10 days versus 1 month in reduced distal radius fractures : A prospective randomized study
- 2018
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Ingår i: Scandinavian Journal of Surgery. - : SAGE Publications. - 1457-4969 .- 1799-7267. ; 107:1, s. 82-90
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: this study aimed to evaluate clinical results after plaster cast fixation for 10 days versus 1 month of moderately displaced and reduced distal radius fractures.Material and Methods: in a prospective randomized study, 109 patients with moderately displaced and conservatively treated distal radius fractures (age ≥50 years) were randomized 10 days after reduction to either removal of the plaster cast and immediate mobilization (active group) or to continued plaster cast fixation for another 3 weeks (control group). Grip strength, pincer strength, range of motion, and pain were assessed at 1, 4, and 12 months after reduction. Clinical outcome was evaluated using three functional assessment scores at 12 months.Results: treatment failed in 3/54 (6%) patients in the active group. one of these patients had the plaster cast reinstituted because of feelings of instability. the fractures in the other two patients displaced severely after mobilization and were therefore treated surgically. for the remaining 51 patients in the active group, the range of wrist motion was slightly better at 1 month compared with the controls, but there were no differences in grip or pincer strength or pain at the 1-month follow-up. there were no differences between the active and control group in any outcome at 4 or 12 months, including functional assessment scores at 12 months.Conclusion: treatment with mobilization 10 days after reduction of moderately displaced distal radius fractures resulted in a few treatment failures compared with none among controls. the only functional benefit for the remaining patients was a small and transient increase in range of motion at the 1-month follow-up. plaster cast removal 10 days after reduction in moderately displaced distal radius fractures is therefore not recommended.
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| 34. |
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| 35. |
- Christersson, Albert, et al.
(författare)
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Comparison of 2D radiography and a semi-automatic CT-based 3D method for measuring change in dorsal angulation over time in distal radius fractures
- 2016
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Ingår i: Skeletal Radiology. - : Springer Science and Business Media LLC. - 0364-2348 .- 1432-2161. ; 45:6, s. 763-769
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Tidskriftsartikel (refereegranskat)abstract
- Objective The aim of the present study was to compare the reliability and agreement between a computer tomography-based method (CT) and digitalised 2D radiographs (XR) when measuring change in dorsal angulation over time in distal radius fractures. Materials and methods Radiographs from 33 distal radius fractures treated with external fixation were retrospectively analysed. All fractures had been examined using both XR and CT at six times over 6 months postoperatively. The changes in dorsal angulation between the first reference images and the following examinations in every patient were calculated from 133 follow-up measurements by two assessors and repeated at two different time points. The measurements were analysed using Bland-Altman plots, comparing intra- and inter-observer agreement within and between XR and CT. Results The mean differences in intra- and inter-observer measurements for XR, CT, and between XR and CT were close to zero, implying equal validity. The average intra- and inter-observer limits of agreement for XR, CT, and between XR and CT were +/- 4.4 degrees, +/- 1.9 degrees and +/- 6.8 degrees respectively. Conclusions For scientific purpose, the reliability of XR seems unacceptably low when measuring changes in dorsal angulation in distal radius fractures, whereas the reliability for the semi-automatic CT-based method was higher and is therefore preferable when a more precise method is requested.
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| 36. |
- Christersson, Albert
(författare)
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Fractures of the distal radius : Factors related to radiographic evaluation, conservative treatment and fracture healing
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Distal radius fractures (DRFs) are one of the most common injuries encountered in orthopaedic practise. Such fractures are most often treated conservatively, but surgical treatment has become increasingly common. This trend is not entirely scientifically basedThe aims of this thesis were threefold: to increase measurement precision in dorsal angulation (DA) on radiographs and computer tomographies (CTs); to assess the results after shortened plaster cast fixation time in reduced DRFs; and to evaluate the feasibility and safety of applying Augment® (rhPDGF-BB/β-TCP) in DRFs.In Paper I and Appendix 1 and 2, a semi-automatic CT-based three-dimensional method was developed to measure change in DA over time in DRFs. This approach proved to be a better (more sensitive) method than radiography in determining changes in DA in fractures of the distal radius.In Paper II, a CT model was used to simulate lateral radiographic views of different radial directions in relation to the X-ray. Using an alternative reference point on the distal radius, precision and accuracy in measuring DA was increased.Paper III and IV are based on a prospective and randomised clinical study (the GitRa trial) that compares clinical and radiographic outcomes after plaster cast removal at 10 days versus 1 month in 109 reduced DRFs. Three patients in the early mobilised group were excluded because of fracture dislocation (n=2) or a feeling of fracture instability (n=1). For the remaining patients in the early mobilised group (51/54) a limited but temporary gain in range of motion, but a slight increase in radiographic displacement were observed. Our results suggest that plaster cast removal at 10 days after reduction of DRFs is not feasible.Paper V is based on a prospective, randomised clinical study (the GEM trial) in which 40 externally fixated DRFs were randomised to rhPDGF-BB/β-TCP into the fracture gap or to the control group. Augment® proved to be convenient and safe during follow-up (24 weeks). However, because of the nature of the study design, the effect on fracture healing could not be determined. A decrease in pin infections was seen in the Augment® group, a finding we could not explain.
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| 37. |
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| 38. |
- Christersson, Albert, et al.
(författare)
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Presurgical localization of infected avascular bone segments in chronic complicated posttraumatic osteomyelitis in the lower extremity using dual-tracer PET/CT.
- 2018
-
Ingår i: EJNMMI Research. - : Springer Science and Business Media LLC. - 2191-219X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Localizing and removing the infected sequestrum in long-standing trauma-related chronic osteomyelitis remains a clinical challenge. PET/CT with 18F-fluorodeoxyglucose (FDG-PET) has a high sensitivity for chronic osteomyelitis and 18F-sodium-fluoride PET/CT (NaF-PET) has a high specificity for identifying non-viable bone. Combining both, high signal on FDG-PET in the bone without signal on NaF-PET could potentially guide surgery to become more precise with curative intent. Eight patients with long-standing (average 22 years) posttraumatic (n = 7) or postoperative (n = 1) chronic osteomyelitis in the lower extremity and with multiple futile attempts for curative surgery were recruited in this prospective pilot study. FDG-PET and NaF-PET were performed within a week in between using standard scanning protocols. The most likely location of the culprit sequestrum was identified and was surgically removed. Based on perioperative tissue cultures, antibiotics were given for 6-8 months. Dual-tracer (FDG- and NaF-PET/CT) was performed again after 12 months to rule out persisting signs of infection.RESULTS: A likely culprit sequestrum could preoperatively be identified by dual-tracer PET in all eight cases and in four cases an additional sequestrum was identified at a location with no clinical sign of infection. The infected necrotic tissue was removed during surgery. Follow-up dual-tracer PET revealed no signs of persistent infection. All patients recovered with no clinical signs of recurrence for a follow-up of mean 4.5 (SD 1.3) years.CONCLUSIONS: Dual-tracer PET/CT with FDG and NaF allows successful precise surgery with curative intent in patients with long-standing complicated posttraumatic chronic osteomyelitis with severely deranged anatomy.
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| 39. |
- Christersson, Albert, et al.
(författare)
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Prospective randomized feasibility trial to assess the use of rhPDGF-BB in treatment of distal radius fractures
- 2015
-
Ingår i: Journal of Orthopaedic Surgery and Research. - : Springer Science and Business Media LLC. - 1749-799X. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Recombinant human platelet-derived growth factor BB (rhPDGF-BB) combined with an osteoconductive scaffold (β-TCP) has been demonstrated to increase bone formation, but rhPDGF-BB has not been studied in human fractures. The purpose of this study was to evaluate the safety and potential use of locally administered rhPDGF-BB/β-TCP (Augment®) in acute wrist fractures.METHODS: Forty patients with unstable distal radial fracture were randomized to closed reduction and external fixation alone (n = 20) or combined with injection of rhPDGF-BB/β-TCP (Augment®) into the fracture (n = 20). All patients were followed for 24 weeks. Outcome was based on adverse events, fracture displacement on radiographs, fracture healing, range of motion, grip strength, pain, and the disability of the arm, shoulder and hand (DASH) score.RESULTS: There were no serious adverse events in the study, but the pin tract infection rate was significantly lower in the Augment® group. There was no difference between the groups in fracture healing time, based on number of healed cortices or fracture displacement. The Augment® group had an early temporary significant decrease in wrist flexion, but no difference in range of motion at 24 weeks. There were no differences between the two treatment groups for any other outcome variables.CONCLUSION: rhPDGF-BB/β-TCP (Augment®) is safe and convenient for local administration into wrist fractures. In this pilot study, we could not detect any reduced healing time in the Augment® group although potential efficacy should be addressed in larger studies.CLINICAL TRIAL REGISTRATION NUMBER: The clinical trial registration number for the study protocol is BMPI-2014-02-E.
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| 40. |
- Christersson, Albert, et al.
(författare)
-
Radiographic results after plaster cast fixation for 10 days versus 1 month in reduced distal radius fractures : a prospective randomised study
- 2016
-
Ingår i: Journal of Orthopaedic Surgery and Research. - : Springer Science and Business Media LLC. - 1749-799X. ; 11
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The aim of this study was to examine whether reduced distal radius fractures can be treated with early mobilisation without affecting the radiographic results.METHODS: In a prospective randomised study, 109 patients (mean age 65.8 (range 50-92)) with moderately displaced distal radius fractures were treated with closed reduction and plaster cast fixation for about 10 days (range 8-13 days) followed by randomisation to one of two groups: early mobilisation (n = 54, active group) or continued plaster cast fixation for another 3 weeks (n = 55, control group).RESULTS: For three patients in the active group (6%), treatment proved unsuccessful because of severe displacement of the fracture (n = 2) or perceived instability (n = 1). From 10 days to 1 month, i.e. the only period when the treatment differed between the two groups, the active group displaced significantly more in dorsal angulation (4.5°, p < 0.001), radial angulation (2.0°, p < 0.001) and axial compression (0.5 mm, p = 0.01) compared with the control group. However, during the entire study period (i.e. from admission to 12 months), the active group displaced significantly more than the controls only in radial angulation (3.2°, p = 0.002) and axial compression (0.7 mm, p = 0.02).CONCLUSIONS: Early mobilisation 10 days after reduction of moderately displaced distal radius fractures resulted in both an increased number of treatment failures and increased displacement in radial angulation and axial compression as compared with the control group. Mobilisation 10 days after reduction cannot be recommended for the routine treatment of reduced distal radius fractures.TRIAL REGISTRATION: ClinicalTrail.gov, NCT02798614 . Retrospectively registered 16 June 2016.
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| 41. |
- Ekström, Wilhelmina, et al.
(författare)
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Functional outcome in treatment of unstable trochanteric and subtrochanteric fractures with the proximal femoral nail and the Medoff sliding plate
- 2007
-
Ingår i: Journal of Orthopaedic Trauma. - 0890-5339 .- 1531-2291. ; 21:1, s. 18-25
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To compare outcome between the proximal femoral nail (PFN) and the Medoff sliding plate (MSP) in patients with unstable trochanteric or subtrochanteric fractures. Methods: This was a consecutive prospective randomized clinical study. In all, 203 patients admitted to two university hospitals with an unstable trochanteric or a subtrochanteric fracture type were included. Surgery was performed with a short intramedullary nail or a dual-sliding plate device. Follow up visits occurred at 6 weeks, 4 months, and 12 months. Functional outcome was measured by walking ability, rising from a chair, curb test, and additional assessments of abductor strength, pain, living conditions, and complications. Results: The ability to walk 15 m at 6 weeks was significantly better in the PFN group compared to the MSP group with an odds ratio 2.2 (P = 0.04, 95% confidence limits 1.03-4.67). No statistical difference in walking ability could be found between trochanteric and subtrochanteric fractures. The major complication rate (8% in the PFN group and 4% in the MSP group) did not differ statistically (P = 0.50) but reoperations were more frequent in the PFN group (9%) compared to the MSP group (1%; P < 0.02). Conclusions: There were no major differences in functional outcome or major complications between the treatment groups. Reasons other than the operated fracture seem to be equally important in determining the long-term functional ability of the patients in our study. An advantage with the MSP was the lower reoperation rate.
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| 42. |
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| 43. |
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| 44. |
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| 45. |
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| 46. |
- Fill, E, et al.
(författare)
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Xuv Spectra of Optical-field-ionized Plasmas
- 1995
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Ingår i: Physical Review E: covering statistical, nonlinear, biological, and soft matter physics. - 1063-651X. ; 51:6, s. 6016-6027
-
Tidskriftsartikel (refereegranskat)
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| 47. |
- Forsgren, Johan, et al.
(författare)
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In Vivo Evaluation of Functionalized Biomimetic Hydroxyapatite for Local Delivery of Active Agents
- 2011
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Ingår i: Journal of Biomaterials and Nanobiotechnology. - : Scientific Research Publishing, Inc.. - 2158-7027 .- 2158-7043. ; 2:2, s. 149-154
-
Tidskriftsartikel (refereegranskat)abstract
- This study was carried out to investigate the biological response in vivo to biomimetic hydroxyapatite implant coatings functionalized with bisphosphonates and bone morphogenetic proteins. The functionalization was carried out by a simple soaking procedure in the operating room immediately prior to surgery. Cylindrical titanium samples with and without coatings were implanted in the distal femoral epiphysis of sheep and retrieved after 6 weeks. The histological analysis proved that all samples were integrated well in the tissue with no signs of intolerance. Fewer osteoclasts were observed in the vicinity of bisphosphonate-functionalized samples and the bone was denser around these samples compared to the other samples. Samples functionalized with bone morphogenetic protein induced more bone/implant contact but showed a more inconsistent outcome with reduced bone density around the samples. This study demonstrates a simple method to functionalize implant coatings, which provides surgeons with an option of patient-specific functionalization of implants. The observed biological impact due to the delivery of active molecules from the coatings suggests that this strategy may also be employed to deliver antibiotics from similar coatings.
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| 48. |
- Fox, Glen A, et al.
(författare)
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Health of herring gulls (Larus argentatus) in relation to breeding location in the early 1990s : III. Effects on the bone tissue
- 2008
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Ingår i: Journal of Toxicology and Environmental Health. - : Informa UK Limited. - 1528-7394 .- 1087-2620. ; 71:21, s. 1448-1456
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Tidskriftsartikel (refereegranskat)abstract
- Health effects associated with the Great Lakes environment were assessed in adult herring gulls (Larus argentatus) in the early 1990s, including the size and quality of their bones. Femurs were excised from 140 individuals from 10 colonies distributed throughout the Great Lakes and 2 reference colonies in Lake Winnipeg (freshwater) and the Bay of Fundy (marine). Femurs of gulls from the Great Lakes differed from the freshwater or marine reference for 9 of 12 variables of size, composition, and strength assessed using peripheral quantitative computed tomography (pQCT) and biomechanical testing. Femurs of Great Lakes gulls were significantly smaller in length (-2.9%), periosteal circumference (-2.4%), and cross-sectional area (-5.4%) than freshwater reference birds. Femurs of the Great Lakes gulls had a lower significant cortical bone mineral content (-8.1%) and density (-2%) than the marine reference. A significant increase in the amount the bone could bend before it broke (+34%) and the energy required to break it (+44%) and a significant decrease (-16.3%) in stiffness during three-point biomechanical bending test were also detected in Great Lakes versus the freshwater gulls. These differences are indicative of impaired mineralization. When divided into high and low 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity equivalent (TCDD-TEQ) colonies, the amount the bone could bend before it broke and the energy required to break it were significantly higher in the high TEQ colonies, but not high polychlorinated biphenyl (PCB) colonies. Breeding location and dietary choices of Great Lakes herring gulls in the early 1990s resulted in modulations of physiological processes that affected the size, mineralization, and biomechanical properties of bone.
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| 49. |
- Gaarde, Mette, et al.
(författare)
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Determination of Radiative Lifetimes of Excited-states In Neutral Gold Using Time-resolved Vacuum-ultraviolet Laser Spectroscopy
- 1994
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Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 50:1, s. 209-213
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Tidskriftsartikel (refereegranskat)abstract
- Natural radiative lifetimes of the states in the highly perturbed 5d10np 2P sequence in neutral gold, Au I, for n = 6-9, as well as of four of the perturbing 5d(9)6s6p 2P states, have been measured. This was done by direct excitation from the ground state with short-pulse vacuum-ultraviolet laser light and time-resolved detection of the laser-induced fluorescence. We found the lifetimes to be tau(6p P-2(1/2))=6.2(2) ns, tau(6p P-2(3/2))=4.7(2) ns, tau(7p P-2(1/2))=6.4(7) ns, tau(7p P-2(3/2))=5.3(7) ns, tau(8p P-2(1/2))=63(3) ns, tau(8p P-2(3/2))=24(2) ns, tau(9p P-2(1/2))=28(2) ns, and tau(9p P-2(3/2))=75(4) ns. For the perturbing states (two states of each term have been observed) we found tau(P-2(1/2), 60983.05 cm-1)=17.5(10) ns, tau(P-2(1/2), 62540.65 cm-1)=6.7(7) ns, tau(P-2(3/2), 58826.30 cm-1)=2.1(15) ns, and tau(P-2(3/2), 63005.62 cm-1)=2.7(15) ns. Furthermore, we have investigated the hyperfine structure of the 6p P-2(3/2) State.
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| 50. |
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