| 1. |
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| 2. |
- Bargholtz, Chr., et al.
(author)
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The WASA detector facility at CELSIUS
- 2008
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In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 594:3, s. 339-350
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Journal article (peer-reviewed)abstract
- The WASA 4 pi multidetector system, aimed at investigating light meson production in light ion collisions and eta meson rare decays at the CELSIUS storage ring in Uppsala is presented. A unique feature of the system is the use of hydrogen pellets as internal targets for the first time. A detailed description of the design, together with the anticipated and achieved performance parameters are given. (C) 2008 Elsevier B.V. All rights reserved.
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| 3. |
- Calén, H., et al.
(author)
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Detector setup for a storage ring with an internal target
- 1996
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In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 379:1, s. 57-75
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Journal article (peer-reviewed)abstract
- A detector setup for the cooler storage ring CELSIUS is described. The setup detects particles produced in interactions between the internal beam and a cluster-jet target. Particles emitted in the forward direction are measured by means of arrays of plastic scintillators and proportional counters. Particles, particularly photons, emitted more isotropically are measured by means of two calorimeters containing CsI(Na) crystals. The performance of the setup is given for neutral meson production in proton-proton and proton-deuteron interactions in the energy range 290-1360 MeV.
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| 4. |
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| 5. |
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| 6. |
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| 7. |
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| 8. |
- Calén, H, et al.
(author)
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Detector setup for a storage ring with an internal target
- 1996
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In: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - : ELSEVIER SCIENCE BV. - 0168-9002. ; 379:1, s. 57-75
-
Journal article (peer-reviewed)abstract
- A detector setup for the cooler storage ring CELSIUS is described. The setup detects particles produced in interactions between the internal beam and a cluster-jet target. Particles emitted in the forward direction are measured by means of arrays of plast
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| 9. |
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| 10. |
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| 11. |
- Meyer, E., et al.
(author)
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The state of the art in beyond 5G distributed massive multiple-input multiple-output communication system solutions
- 2022
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In: Open Research Europe. - : F1000 Research Ltd. - 2732-5121. ; 2
-
Research review (peer-reviewed)abstract
- Beyond fifth generation (5G) communication systems aim towards data rates in the tera bits per second range, with improved and flexible coverage options, introducing many new technological challenges in the fields of network architecture, signal pro- cessing, and radio frequency front-ends. One option is to move towards cell-free, or distributed massive Multiple-Input Multiple-Output (MIMO) network architectures and highly integrated front-end solutions. This paper presents an outlook on be- yond 5G distributed massive MIMO communication systems, the signal processing, characterisation and simulation challenges, and an overview of the state of the art in millimetre wave antennas and electronics.
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| 12. |
- Patel, T. J., et al.
(author)
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Sarcomere strain and heterogeneity correlate with injury to frog skeletal muscle fiber bundles
- 2004
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In: J Appl Physiol. - : American Physiological Society. - 8750-7587. ; 97:5, s. 1803-13
-
Journal article (peer-reviewed)abstract
- Sarcomere length and first-order diffraction line width were measured by laser diffraction during elongation of activated frog tibialis anterior muscle fiber bundles (i.e., eccentric contraction) at nominal fiber strains of 10, 25, or 35% (n = 18) for 10 successive contractions. Tetanic tension, measured just before each eccentric contraction, differed significantly among strain groups and changed dramatically during the 10-contraction treatment (P < 0.01). Average maximum tetanic tension for the three groups measured before any treatment was 203.7 +/- 6.8 kN/m2, but after the 10-eccentric contraction sequence decreased to 180.3 +/- 3.8, 125.1 +/- 7.8, and 78.3 +/- 5.1 kN/m2 for the 10, 25, and 35% strain groups, respectively (P < 0.0001). Addition of 10 mM caffeine to the bathing medium decreased the loss of tetanic tension in the 10% strain group but had only a minimal effect on either the 25 or 35% strain groups. Diffraction pattern line width, a measure of sarcomere length heterogeneity, increased significantly with muscle activation and then continued to increase with successive stretches of the activated muscle. Line width increase after each stretch was significantly correlated with the lower yield tension of the successive contractile record. These data demonstrate a direct association and, perhaps, a causal relationship between sarcomere strain and fiber bundle injury. They also demonstrate that muscle injury is accompanied by a progressive increase in sarcomere length heterogeneity, yielding lower yield tension as injury progresses.
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| 13. |
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| 14. |
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| 15. |
- Andersson, Jonny K, 1972, et al.
(author)
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Patients with triangular fibrocartilage complex injuries and distal radioulnar joint instability have reduced rotational torque in the forearm.
- 2016
-
In: The Journal of hand surgery, European volume. - : SAGE Publications. - 2043-6289. ; 41:7, s. 732-8
-
Journal article (peer-reviewed)abstract
- A total of 20 patients scheduled for wrist arthroscopy, all with clinical signs of rupture to the triangular fibrocartilage complex and distal radioulnar joint instability, were tested pre-operatively by an independent observer for strength of forearm rotation. During surgery, the intra-articular pathology was documented by photography and also subsequently individually analysed by another independent hand surgeon. Arthroscopy revealed a type 1-B injury to the triangular fibrocartilage complex in 18 of 20 patients. Inter-rater reliability between the operating surgeon and the independent reviewer showed absolute agreement in all but one patient (95%) in terms of the injury to the triangular fibrocartilage complex and its classification. The average pre-operative torque strength was 71% of the strength of the non-injured contralateral side in pronation and supination. Distal radioulnar joint instability with an arthroscopically verified injury to the triangular fibrocartilage complex is associated with a significant loss of both pronation and supination torque.
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| 16. |
- Bae, Juhee, et al.
(author)
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Towards a methodological framework to address data challenges in lake water quality predictions
- 2024
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In: 3rd International Conference on Water Management in Changing Conditions. - : European Water Association; IFAT. ; , s. 5-8
-
Conference paper (peer-reviewed)abstract
- Climate change has impacted global temperatures, triggering extreme weather and adverse environmental effects. In Sweden, these changes have caused shifts in weather patterns, leading to disruptions in infrastructure. This, in turn, has influenced water turbidity levels, negatively impacting water quality. To tackle these issues, a study was conducted using machine learning to predict turbidity with six meteorological variables collected for two years. Our preliminary research showed a substantial influence of seasonal changes on water turbidity, especially air temperature. Identifying supporting indicators such as lagged features is crucial and considerably improved the turbidity prediction performance for two of the machine learning models used. However, the study also identified challenges like data collection and uncertainty issues. We recommend improving data collection quality with higher frequency, minimizing geographical gaps between data collection points, sharing calibration assumptions, checking the sensors regularly, and accounting for data anomalies. Understanding these challenges and their potential implications could lead to more methodological enhancements.
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| 17. |
- Bersch, Ines, et al.
(author)
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Long-term effect of task-oriented functional electrical stimulation in chronic Guillain Barre syndrome-a single-subject study
- 2021
-
In: Spinal Cord Series and Cases. - : Springer Science and Business Media LLC. - 2058-6124. ; 7:1
-
Journal article (peer-reviewed)abstract
- Objective Functional electrical stimulation (FES) can enhance motor learning of hand fine motor skills in neurological diseases with upper motoneuron lesions. Nevertheless, FES is rarely applied in patients with chronic Guillan-Barre syndrome (GBS) with preserved deep tendon reflexes allowing for stimulation via nerve. This single case report documents the results of an FES-supported, task-oriented grasp training to regain hand closure and pinch grip. Study design Single-subject repeated measures study. Setting International FES Centre (R), Swiss Paraplegic Centre Nottwil. Methods Three individually defined goals were formulated and scored by using the goal attainment scale. With a focus on these goals, FES was applied bilaterally to improve hand closure and pinch grip. Based on principles of motor learning FES was executed together with task-oriented movements. The hand closure distance (cm) between the tip of the middle finger and the palmar side of the hand was measured and the achievement of personal, predefined goals evaluated. Results After 16 weeks of daily stimulation, hand closure could be voluntarily performed. Regained opposition of the thumb to the index finger enabled improved individually defined fine motor control. Restored function remained unchanged in the follow-up at 6 months without stimulation. Conclusion Improving fine motor skills in chronic GBS with intact deep tendon reflexes was possible utilizing FES combined with task-oriented grasp training. These improvements were maintained over time indicating the combination was effective in promoting functionally meaningful motor gains.
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| 18. |
- Biering-Sørensen, F, et al.
(author)
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International Spinal Cord Injury Upper Extremity Basic Data Set.
- 2014
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In: Spinal cord. - : Springer Science and Business Media LLC. - 1476-5624 .- 1362-4393. ; 52:9, s. 652-657
-
Journal article (peer-reviewed)abstract
- Objective:To develop an International Spinal Cord Injury (SCI) Upper Extremity Basic Data Set as part of the International SCI Data Sets, which facilitates consistent collection and reporting of basic upper extremity findings in the SCI population.Setting:International.Methods:A first draft of a SCI Upper Extremity Data Set was developed by an international working group. This was reviewed by many different organisations, societies and individuals over several months. A final version was created.Variables:The final version of the International SCI Upper Extremity Data Set contains variables related to basic hand-upper extremity function, use of assistive devices, SCI-related complications to upper extremity function and upper extremity/hand reconstructive surgery. Instructions for data collection and the data collection form are freely available on the ISCoS website (www.iscos.org.uk).Conclusion:The International SCI Upper Extremity Basic Data Set will facilitate consistent collection and reporting of basic upper extremity findings in the SCI population.
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| 19. |
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| 20. |
- Bunketorp Käll, Lina, 1975, et al.
(author)
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Adaptive motor cortex plasticity following grip reconstruction in individuals with tetraplegia
- 2018
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In: Restorative Neurology and Neuroscience. - : IOS Press. - 0922-6028 .- 1878-3627. ; 36:1, s. 73-82
-
Journal article (peer-reviewed)abstract
- Background: Tendon transfer is a surgical technique for restoring upper limb motor control in patients with cervical spinal cord injuries (SCI), and offers a rare window into cortical neuroplasticity following regained arm and hand function. Objective: Here, we aimed to examine neuroplasticity mechanisms related to re-established voluntary motor control of thumb flexion following tendon transfer. Methods: We used functional Magnetic Resonance Imaging (fMRI) to test the hypothesis that restored limb control following tendon transfer is mediated by activation of that limb's area of the primary motor cortex. We examined six individuals with tetraplegia who underwent right-sided surgical grip reconstruction at Sahlgrenska University Hospital, Sweden. All were right-handed males, with a SCI at the C6 or C7 level, and a mean age of 40 years (range = 31-48). The average number of years elapsed since the SCI was 13 (range = 6-26). Six right-handed gender-and age-matched control subjects were included (mean age 39 years, range = 29-46). Restoration of active thumb flexion in patients was achieved by surgical transfer of one of the functioning elbow flexors (brachioradialis), to the paralyzed thumb flexor (flexor pollicis longus). We studied fMRI responses to isometric right-sided elbow flexion and key pinch, and examined the cortical representations within the left hemisphere somatomotor cortex a minimum of one year after surgery. Results: Cortical activations elicited by elbow flexion did not differ in topography between patients and control participants. However, in contrast to control participants, patients' cortical thumb flexion activations were not topographically distinct from their elbow flexion activations. Conclusion: This result speaks against a topographic reorganization in which the thumb region regains thumb control following surgical tendon transfer. Instead, our findings suggest a neuroplastic mechanism in which motor cortex resources previously dedicated to elbow flexion adapt to control the thumb.
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| 21. |
- Bäckström, Erica, et al.
(author)
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Uncovering the regional localization of inhaled salmeterol retention in the lung
- 2018
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In: Drug Delivery. - : Taylor & Francis Group. - 1071-7544 .- 1521-0464. ; 25:1, s. 838-845
-
Journal article (peer-reviewed)abstract
- Treatment of respiratory disease with a drug delivered via inhalation is generally held as being beneficial as it provides direct access to the lung target site with a minimum systemic exposure. There is however only limited information of the regional localization of drug retention following inhalation. The aim of this study was to investigate the regional and histological localization of salmeterol retention in the lungs after inhalation and to compare it to systemic administration. Lung distribution of salmeterol delivered to rats via nebulization or intravenous (IV) injection was analyzed with high-resolution mass spectrometry imaging (MSI). Salmeterol was widely distributed in the entire section at 5 min after inhalation, by 15 min it was preferentially retained in bronchial tissue. Via a novel dual-isotope study, where salmeterol was delivered via inhalation and d(3)-salmeterol via IV to the same rat, could the effective gain in drug concentration associated with inhaled delivery relative to IV, expressed as a site-specific lung targeting factor, was 5-, 31-, and 45-fold for the alveolar region, bronchial sub-epithelium and epithelium, respectively. We anticipate that this MSI-based framework for quantifying regional and histological lung targeting by inhalation will accelerate discovery and development of local and more precise treatments of respiratory disease.
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| 22. |
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| 23. |
- Ekström, C, et al.
(author)
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Hydrogen pellet targets for circulating particle beams
- 1996
-
In: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - 0168-9002. ; 371:3, s. 572-574
-
Journal article (peer-reviewed)abstract
- A novel internal-target system producing a stream of frozen hydrogen microspheres (pellets) has been installed at the CELSIUS ion storage ring. From test experiments in which the pellet stream crosses the beam of stored protons and deuterons it is conclud
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| 24. |
- Farid, N., et al.
(author)
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Exploring Uniformity of Reverberation Chambers: Insights from Antenna Reflection Coefficient
- 2024
-
In: 18th European Conference on Antennas and Propagation, EuCAP 2024.
-
Conference paper (peer-reviewed)abstract
- Reverberation chambers are widely recognized as a time-efficient testing facility for various applications. The spatial uniformity based on the power transfer function is a critical characteristic of the chamber that affects the measurement uncertainty. To gain more insights into the chamber behavior we introduce a complementary metric: the K-gamma factor. This metric, inspired by the well-established K-factor, quantifies the unstirred contributions of the chamber for each antenna individually and is highly sensitive to the chamber configuration and antenna placement. Analyzing this metric can help identify any undesired effect, such as specular reflections, and, ultimately, improve measurement accuracy. To highlight the usefulness of this metric, two different loading configurations of a reverberation chamber at millimeter-wave frequencies are evaluated as examples.
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| 25. |
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| 26. |
- Fridén, B, et al.
(author)
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The effect of estramustine derivatives on microtubule assembly in vitro depends on the charge of the substituent.
- 1991
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In: Biochemical pharmacology. - 0006-2952. ; 42:5, s. 997-1006
-
Journal article (peer-reviewed)abstract
- Estramustine, and derivatives of estramustine with a charged substituent at position 17 on the estrogen moiety, have been investigated for their effects on bovine brain microtubules in vitro. The negatively charged estramustine phosphate has been found previously to be a microtubule-associated protein (MAP)-dependent microtubule inhibitor [Wallin M, Deinum J and Fridén B, FEBS Lett 179: 289-293, 1985]. In the present study the binding of estramustine phosphate to MAP2 and tau was investigated. Both these MAPs were found to have two to three binding sites for estramustine phosphate which is compatible with the reported number of basic amino acid repeats of these MAPs, considered to be the ultimate tubulin binding domains. The Kd for the binding of estramustine phosphate to MAP2 was estimated to be 20 microM at 4 degrees, and for the binding of tau, 200 microM. The rate of dissociation was very low (T1/2 greater than 2 hr), which indicates that the binding of estramustine phosphate may stabilize the protein-drug complex by changing the protein conformation. Two new negatively charged estramustine derivatives, estramustine sulphate and estramustine glucuronide, were found to be similar MAP-dependent microtubule inhibitors. The concentration for 50% inhibition of assembly was 100 microM for the sulphate derivative, the same as found previously for estramustine phosphate, and 250 microM for the more bulky estramustine glucuronide. A positively charged derivative, estramustine sarcosinate, did not inhibit microtubule assembly or alter the composition of the coassembled MAPs. The morphology of the microtubules was, however, affected. The uncharged estramustine bound to both tubulin and MAPs, but no effects were seen on microtubule assembly, the composition of coassembled MAPs or the microtubule morphology. Our results suggest that only negatively charged estramustine derivatives have a MAP-dependent microtubule inhibitory effect. The two new negatively charged derivatives could therefore be valuable tools in the study of tubulin-MAP interactions. The results also confirm that these interactions between tubulin and MAPs are mainly electrostatic.
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| 27. |
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| 28. |
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| 29. |
- Fridén, H, et al.
(author)
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Low temperature EPR and MCD studies on cytochrome b-558 of the Bacillus subtilis succinate: quinone oxidoreductase indicate bis-histidine coordination of the heme iron
- 1990
-
In: Biochimica et Biophysica Acta - Bioenergetics. - 0005-2728. ; 1041:2, s. 207-215
-
Journal article (peer-reviewed)abstract
- Bacillus subtilis cytochrome b-558 was expressed in high amounts in Escherichia coli, solubilized from membranes with detergent and purified free from other hemoproteins. The cytochrome possibly contains two heme groups. To determine the axial ligands to the low-spin heme and the heme rhombicity, the cytochrome was analyzed using low-temperature electron paramagnetic resonance (EPR) and magnetic circular dichroism (MCD) spectroscopy. The combined results exclude bis-methionine, bis-lysine and histidine-methionine coordination. Bis-histidine coordination of the heme(s) with a near perpendicular orientation of the imidazole planes is strongly suggested by the highly axial low-spin EPR signals and the intense near infrared MCD spectrum (Δϵ=380 M−1·cm−1 at 4.2 K and 5 T) of the charge-transfer band at 1600 nm.
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| 30. |
- Fridén, Jan, 1953, et al.
(author)
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Mechanical feasibility of immediate mobilization of the brachioradialis muscle after tendon transfer
- 2010
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In: The Journal of Hand Surgery. - : Elsevier BV. - 1531-6564 .- 0363-5023. ; 35:9, s. 1473-1478
-
Journal article (peer-reviewed)abstract
- PURPOSE: Tendon transfer is often used to restore key pinch after cervical spinal cord injury. Current postoperative recommendations include elbow immobilization in a flexed position to protect the brachioradialis-flexor pollicis longus (BR-FPL) repair. The purpose of this study was to measure the BR-FPL tendon tension across a range of wrist and elbow joint angles to determine whether joint motion could cause repair rupture. METHODS: We performed BR-to-FPL tendon transfers on fresh-frozen cadaveric arms (n = 8) and instrumented the BR-FPL tendon with a buckle transducer. Arms were ranged at 4 wrist angles from 45 degrees of flexion to 45 degrees of extension and 8 elbow angles from 90 degrees of flexion to full extension, measuring tension across the BR-FPL repair at each angle. Subsequently, the BR-FPL tendon constructs were removed and elongated to failure. RESULTS: Over a wide wrist and elbow range of motion, BR-FPL tendon tension was under 20 N. Two-way analysis of variance with repeated measures revealed a significant effect of wrist joint angle (p<.001) and elbow joint angle (p<.001) with significant interaction between elbow and joint angles (p<.001). Because the failure load of the repair site was 203 +/- 19 N, over 10 times the loads that would be expected to occur at the repair site, our results demonstrate that the repair has a safety factor of at least 10. CONCLUSIONS: Our tendon force measurements support the assertion that the elbow joint need not be immobilized when the BR is used as a donor muscle in tendon transfer to the FPL. This is based on the fact that maximum passive tendon tension was only about 20 N in our cadaveric model and the failure strength of this specific repair was over 200 N. We suggest that it is possible to consider performing multiple tendon transfers in a single stage, avoiding immobilization, which may adversely affect functional recovery. These results must be qualified by the fact that issues unique to living tissues such as postoperative edema and tendon gliding cannot be accounted for by this cadaveric model.
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| 31. |
- Fridén, Jan, 1953, et al.
(author)
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Simultaneous powering of forearm pronation and key pinch in tetraplegia using a single muscle-tendon unit.
- 2012
-
In: The Journal of hand surgery, European volume. - 2043-6289. ; 37:4, s. 323-328
-
Journal article (peer-reviewed)abstract
- This study clinically assessed the concept that both thumb flexion and forearm pronation can be restored by brachioradialis (BR)-to-flexor pollicis longus (FPL) tendon transfer if the BR is passed dorsal to the radius. Six patients [two women and four men, mean age 32.3 years (SD 4.9, range 23-56)] underwent BR-to-FPL transfer dorsal to the radius and through the interosseous membrane (IOM). Lateral key pinch strength and pronation range of motion (ROM) were measured 1 year after surgery. A group of six patients [two women and four men, mean age 31.2 years (SD 5.0, range 19-52)] who underwent traditional palmar BR-to-FPL was included for comparison. Postoperative active pronation was significantly greater in the dorsal transfer group compared to the palmar group [149 (SD 6) and 75 (SD 3), respectively] and pinch strength was similar in the two groups [1.28 (SD 0.16) kg and 1.20 (SD0.21) kg, respectively]. We conclude that it is feasible to reconstruct lateral key pinch and forearm pronation simultaneously using only the BR motor.
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| 32. |
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| 33. |
- Fridén, Mikael E, 1984-
(author)
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Development of Methods for Analysis of Valuable Compounds in By-products from Agricultural and Forestry Industrial Sectors
- 2015
-
Doctoral thesis (other academic/artistic)abstract
- A growing interest in sustainable development has made efficient utilisation of starting materials and, if they occur, by-products become increasingly important. Vast amounts of by-products are generated by the forestry and food industry. Incineration for energy production is one way to make use of these by-products but some of them contain compounds that would have an increased value if they were extracted, so called “high value species”. The by-products are often very complex, so reliable methods for analysis of the high value species are required in the development of processes to utilise them. A wide range of compounds can be analysed using chromatographic separation coupled to mass spectrometry, making it a powerful tool in the evaluation of methods for extracting high value species from industry by-products.This thesis is based on four studies of potential high value species. In the first study, methods were developed to differentiate isobaric flavonoids and then use this knowledge to determine the identity of the flavonoids in three different plant extracts. In the second study, three different methods to extract betulin from birch bark were evaluated regarding extracted amount and purity of betulin. One of the methods was then investigated in industrial scale using a model approach. In the third study, the flavonoid contents of lovage were determined and other major extracted compounds were investigated by high performance liquid chromatography coupled to electrospray ionisation mass spectrometry. Gas chromatography and supercritical fluid chromatography were used to obtain complementary information about major components. In the fourth study, high resolution mass spectrometry utilising two different types of fragmentation was used with the purpose of overcoming the shortcomings of the methods developed in the first study. The results indicated that it would be possible to develop methods compatible with chromatographic separation for differentiating different types of isobaric substituents. The ability of performing sequential fragmentation was used to investigate some isobaric aglycones by creating spectral trees, and unique pathways were found for each of them.
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| 34. |
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| 35. |
- Fridén, Mikael E, 1984-, et al.
(author)
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Evaluation and analysis of environmentally sustainable methodologies for extraction of betulin from birch bark with a focus on industrial feasibility
- 2016
-
In: Green Chemistry. - : Royal Society of Chemistry (RSC). - 1463-9262 .- 1463-9270. ; 18:2, s. 516-523
-
Journal article (peer-reviewed)abstract
- Betulin from birch bark was extracted using two principally different extraction methodologies - classical Reflux Boiling (RB) and Pressurized Liquid Extraction (PLE). The extraction methods were analyzed based on both recovery and purity as well as for RB industrial feasibility. The purity and recovery for the different extraction methods were analyzed using High Performance Liquid Chromatography (HPLC) coupled with three different detection principles: Diode Array Detection (DAD), Mass Spectrometry (MS) and Charged Aerosol Detection (CAD). The chromatographic purity was determined by all detections whereas the DAD was used also for complementary gravimetric calculations of the purity of the extracts. The MS detection (in MS and MS/MS modes) was mainly used to characterize the impurities. Two steps to increase the purity of RB extracts were evaluated - pre-boiling the bark in water and precipitation by adding water to the extract. Finally, the methods were compared in terms of amounts of betulin produced and solvent consumed. The RB method including a precipitation step produced the highest purity of betulin. However, results indicate that PLE using three cycles with the precipitation step gives similar purities as for RB. The PLE method produced up to 1.6 times higher amount of extract compared to the RB method. However, the solvent consumption (liter solvent per gram product) for PLE was around 4.5 times higher as compared to the classical RB. PLE performed with only one extraction cycle gave results more similar to RB with 1.2 times higher yield and 1.4 times higher solvent consumption. The RB process was investigated on an industrial scale using a model approach and several important key-factors could be identified. The most energy demanding step was the recycling of extraction solvent which motivates that solvent consumption should be kept low and calculations show a great putative energy reduction by decreasing the ethanol concentration used in the RB process to lower than 90%.
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| 36. |
- Fridén, Mikael E., et al.
(author)
-
Strategies for differentiation of isobaric flavonoids using liquid chromatography coupled to electrospray ionization mass spectrometry
- 2014
-
In: Journal of Mass Spectrometry. - : Wiley. - 1076-5174 .- 1096-9888. ; 49:7, s. 646-663
-
Journal article (peer-reviewed)abstract
- Flavonoids are a class of secondary plant metabolites existing in great variety in nature. Due to this variety, identification can be difficult, especially as overlapping compounds in both chromatographic separations and mass spectrometric detection are common. Methods for distinguishing isobaric flavonoids using MS2 and MS3 have been developed. Chromatographic separation of various plant extracts was done with RP-HPLC and detected with positive ESI-MS operated in information-dependent acquisition (IDA) mode. Two methods for the determination of flavonoid identity and substitution pattern, both featuring IDA criteria, were used together with the HPLC equipment. A third method where the collision energy was ramped utilized direct infusion. With the developed strategies, it is possible to differentiate between many isobaric flavonoids. Various classes of flavonoids were found in all of the plant extracts, in the red onion extract 45 components were detected and for 29 of them the aglycone was characterized, while the substituents were tentatively identified for 31 of them. For the strawberry extract, those numbers were 66, 30 and 60, and for the cherry extract 99, 56 and 71. The great variety of flavonoids, several of them isobaric, found in each of the extracts highlights the need for reliable methods for flavonoid characterization. Methods capable of differentiating between most of the isobars analyzed have been developed.
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| 37. |
- Gerdle, Björn, 1953-, et al.
(author)
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The influences of muscle fibre proportions and areas upon EMG during maximal dynamic knee extensions
- 2000
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In: European Journal of Applied Physiology and Occupational Physiology. - 0301-5548 .- 1432-1025. ; 81:1-2
-
Journal article (peer-reviewed)abstract
- This study is an investigation of the relationship between muscle morphology and surface electromyographic (EMG) parameters [mean frequency of the power spectrum (MNF), signal amplitude (root mean square, RMS) and the signal amplitude ratio (SAR, i.e. the ratio between the RMS level during the passive part of the contraction cycle and the RMS level during the active part of the contraction cycle)] during 100 maximal dynamic knee extensions at 90░.s-1. Each contraction cycle comprised of 1 s of active knee extension and 1 s of passive knee flexion. The surface EMG was recorded from the vastus lateralis muscle. Twenty clinically healthy subjects participated in the study, and muscle biopsy samples of the vastus lateralis were obtained from 19 of those subjects. The relationships between muscle morphology and EMG were investigated at three stages of the test: initially, during the fatigue phase (initial 40 contractions), and at the endurance level (the final 50 contractions). Major findings on correlations are that SAR and MNF tended to correlate positively with the proportion of type 1 fibres, and RMS correlated positively with the proportion of type 2 muscle fibres. The muscle fibre areas showed little correlation with the EMG variables under investigation. The results of the present study showed that the three EMG variables of a dynamic endurance test that were investigated (RMS, MNF and SAR were clearly correlated with the proportions of the different fibre types, but only to a small extent with fibre areas. These findings contradict some of the theoretical models of the EMG, especially for parameters in the frequency domain.
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| 38. |
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| 39. |
- Hamm, Gregory R., et al.
(author)
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Revealing the Regional Localization and Differential Lung Retention of Inhaled Compounds by Mass Spectrometry Imaging
- 2020
-
In: Journal of Aerosol Medicine. - : Mary Ann Liebert Inc. - 1941-2711 .- 1941-2703. ; 33:1, s. 43-53
-
Journal article (peer-reviewed)abstract
- Background: For the treatment of respiratory disease, inhaled drug delivery aims to provide direct access to pharmacological target sites while minimizing systemic exposure. Despite this long-held tenet of inhaled therapeutic advantage, there are limited data of regional drug localization in the lungs after inhalation. The aim of this study was to investigate the distribution and retention of different chemotypes typifying available inhaled drugs [slowly dissolving neutral fluticasone propionate (FP) and soluble bases salmeterol and salbutamol] using mass spectrometry imaging (MSI).Methods: Salmeterol, salbutamol, and FP were simultaneously delivered by inhaled nebulization to rats. In the same animals, salmeterol-d(3), salbutamol-d(3), and FP-d(3) were delivered by intravenous (IV) injection. Samples of lung tissue were obtained at 2- and 30-minute postdosing, and high-resolution MSI was used to study drug distribution and retention.Results: IV delivery resulted in homogeneous lung distribution for all molecules. In comparison, while inhalation also gave rise to drug presence in the entire lung, there were regional chemotype-dependent areas of higher abundance. At the 30-minute time point, inhaled salmeterol and salbutamol were preferentially retained in bronchiolar tissue, whereas FP was retained in all regions of the lungs.Conclusion: This study clearly demonstrates that inhaled small molecule chemotypes are differentially distributed in lung tissue after inhalation, and that high-resolution MSI can be applied to study these retention patterns.
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| 40. |
- Hedlund, E., et al.
(author)
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A new test stand for heavy ion induced gas desorption measurements at TSL
- 2008
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In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 586:3, s. 377-381
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Journal article (peer-reviewed)abstract
- In several experiments at CERN, GSI and BNL it has been found that the lifetime of highly energetic heavy ions in synchrotrons decreases with increasing number of injected ions. This phenomenon occurs due to the collisions of beam ions and residual gas molecules leading to the change of charge of the ions and their loss on the vacuum chamber walls, which in turn cause ion-induced gas desorption and further pressure increase. To gain a deeper understanding of the ion-induced desorption process in the energy range 5-45 MeV/u, a dedicated test stand was built at the end of the K beamline at The Svedberg Laboratory (TSL) in Uppsala, Sweden. The energy range was chosen due to the fact that the injection energy of the heavy ion synchrotron SIS18 at GSI will be 10 MeV/u, and that there are insufficient data in this energy range. A Test Particle Monte-Carlo model of the experimental set-up was build-up, run and analysed for different sample configurations. An important result is that for the same sample material the desorption yield from a flat sample causes a 1.58 times larger pressure increase than that of a tubular sample. A detailed explanation of the set-up is presented.
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| 43. |
- Huisstede, Bionka M A, et al.
(author)
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Consensus on a Multidisciplinary Treatment Guideline for De Quervain Disease: Results From the European HANDGUIDE Study.
- 2014
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In: Physical therapy. - : Oxford University Press (OUP). - 1538-6724 .- 0031-9023. ; 94:8, s. 1095-1110
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Journal article (peer-reviewed)abstract
- ObjectiveTo achieve consensus on a multidisciplinary treatment guideline for De Quervain's disease.MethodsA European Delphi consensus strategy was initiated. A systematic review reporting on the effectiveness of surgical and non-surgical interventions was conducted and published, and used as an evidence-based starting point for this study. In total, 35 experts (hand therapists/hand surgeons selected by the national member associations of their European federations, and Physical Medicine & Rehabilitation physicians) participated in the Delphi consensus strategy. Each Delphi round consisted of a questionnaire, an analysis and a feedback report.ResultsConsensus was achieved on the description, symptoms and diagnosis of De Quervain's disease. The experts agreed that patients with this disorder should always receive instructions and that these instructions should be combined with another form of treatment and should not be used as a sole treatment. Instructions combined with NSAIDs, splinting, NSAIDs plus splinting, corticosteroid injection, corticosteroid injections plus splinting, or surgery were considered suitable treatment options. Details on the use of instructions, NSAIDs, splinting, corticosteroid injections, and surgery were described. Main factors for selecting one of the above-mentioned treatment options were identified: severity and duration of the disorder, and previous treatments given. A relation between the severity and duration, and choice of therapy was indicated by the experts and reported in the guideline.ConclusionsThis multidisciplinary treatment guideline may help in the treatment of and research on De Quervain's disease.
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| 44. |
- Huisstede, Bionka M A, et al.
(author)
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Dupuytren disease : european hand surgeons, hand therapists, and physical medicine and rehabilitation physicians agree on a multidisciplinary treatment guideline: results from the HANDGUIDE Study
- 2013
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In: Plastic and reconstructive surgery (1963). - : Ovid Technologies (Wolters Kluwer Health). - 0032-1052 .- 1529-4242. ; 132:6, s. 964e-976e
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Journal article (peer-reviewed)abstract
- BACKGROUND:Multidisciplinary treatment guidelines for Dupuytren disease can aid in optimizing the quality of care for patients with this disorder. Therefore, this study aimed to achieve consensus on a multidisciplinary treatment guideline for Dupuytren disease.METHODS:A European Delphi consensus strategy was initiated. A systematic review reporting on the effectiveness of interventions was conducted and used as an evidence-based starting point for this study. In total, 39 experts (hand surgeons, hand therapists, and physical medicine and rehabilitation physicians) participated in the Delphi consensus strategy. Each Delphi round consisted of a questionnaire, an analysis, and a feedback report.RESULTS:After four Delphi rounds, consensus was achieved on the description, symptoms, and diagnosis of Dupuytren disease. No nonsurgical interventions were included in the guideline. Needle and open fasciotomy, and a limited fasciectomy and dermofasciectomy, were seen as suitable surgical techniques for Dupuytren disease. Factors relevant for choosing one of these surgical techniques were identified and divided into patient-related (age, comorbidity), disease-related (palpable cord, previous surgery in the same area, skin involvement, time of recovery, recurrences), and surgeon-related (years of experience) factors. Associations of these factors with the choice of a specific surgical technique were reported in the guideline. Postsurgical rehabilitation should always include instructions and exercise therapy; postsurgical splinting should be performed on indication. Relevant details for the use of surgical and postsurgical interventions were described.CONCLUSION:This treatment guideline is likely to promote further discussion on related clinical and scientific issues and may therefore contribute to better treatment of patients with Dupuytren disease.
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| 45. |
- Huisstede, Bionka M A, et al.
(author)
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Multidisciplinary Consensus Guideline for Managing Trigger Finger: Results From the European HANDGUIDE Study.
- 2014
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In: Physical therapy. - : Oxford University Press (OUP). - 1538-6724 .- 0031-9023. ; 94:10, s. 1421-1433
-
Journal article (peer-reviewed)abstract
- BackgroundTrigger finger is characterized by -sometimes painful- snapping or locking when flexing the finger. Although trigger finger is frequently seen in clinical practice, no standard treatment protocol has been established as 'best practice'.ObjectiveTo achieve consensus on a multidisciplinary treatment guideline for trigger finger.DesignA European Delphi consensus strategy was initiated. Systematic reviews reporting on the effectiveness of surgical and non-surgical interventions were conducted and used as an evidence-based starting point for this study.SettingIn total, 35 experts (hand therapists /hand surgeons selected by the national member associations of their European federations, and Physical Medicine & Rehabilitation (PM&R) physicians) participated in the Delphi consensus strategy.MeasurementsEach Delphi round consisted of a questionnaire, an analysis and a feedback report.ResultsAfter four Delphi rounds, consensus was achieved on the description, symptoms, and diagnosis of trigger finger. The experts agreed that splinting, corticosteroid injections, corticosteroid injections plus splinting, and surgery are suitable treatment options. Relevant details for the use of splinting, corticosteroid injections, and surgery were described. Main factors for selecting one of these treatment options were identified as severity and duration of the disease, and previous treatments received. A relation between the severity/duration and choice of therapy was indicated by the experts and reported on in the guideline.LimitationsThe results represent a group's opinion at a given point in time. When the evidence for the effectiveness of interventions increases, experts' opinions will change and the guideline should be re-evaluated and adjusted in view of these new insights.ConclusionsThis multidisciplinary treatment guideline may help involved therapists and physicians in the treatment of trigger finger, and indicate areas requiring additional research.
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| 48. |
- Iupikov, Oleg, 1983, et al.
(author)
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Hybrid OTA Chamber for Multi-Directional Testing of Wireless Devices: Plane Wave Spectrum Generator Design and Experimental Demonstration
- 2022
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In: IEEE Transactions on Antennas and Propagation. - 0018-926X .- 1558-2221. ; 70:11, s. 10974-10987
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Journal article (peer-reviewed)abstract
- This paper investigates practical implementation aspects of a novel hybrid chamber concept that has been recently introduced for over-the-air testing of wireless devices. The chamber allows to synthesize a spectrum of plane waves (PWs) incident on a device under test from a wide range of angles-of-arrival (AoAs) through exploiting multiple field scattering inside the overmoded waveguide chamber. An optimal design approach for the plane wave spectrum generator (PWSG) array inside the chamber is presented considering: (i) array antenna impedance matching for the desired test zone (TZ) quality and AoAs range; (ii) an operational frequency bandwidth of the test environment and an instantaneous signal bandwidth; and (iii) the impact of the PWSG excitation errors. A robust linearly constrained minimum variance (LCMV) beamformer is formulated to realize the desired test environment over a wide frequency band, while accounting for the varying number of the waveguide propagating modes as excited by the PWSG array. Numerical simulations and measurements with the first prototype of the hybrid chamber for FR1 frequency band (~3.5 GHz) are presented. This prototype includes a 7 × 7 bowtie antenna element PWSG array, a 1.00 × 1.25 × 1.75 m metal waveguide chamber, an off-line optimal array beamforming setup, and a planar scanner for the TZ characterization.
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| 49. |
- Iupikov, Oleg, 1983, et al.
(author)
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The Hybrid Chamber for OTA measurements: Plane Wave Spectrum Quality Vs. Dynamic Range Trade-off
- 2022
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In: 2022 16th European Conference on Antennas and Propagation, EuCAP 2022.
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Conference paper (peer-reviewed)abstract
- In this paper, the trade-off between the quality of the plane wave spectrum synthesized in the test zone of the hybrid over-the-air (OTA) chamber and factors affecting the dynamic range of this measurement system is investigated. The hybrid chamber performance is compared to a plane wave generator (PWG) in free space. The performance evaluation is focused on the field radiated into the test zone (TZ) while maintaining its quality according to 3GPP specification. It is demonstrated that a good quality can be achieved for the synthesized plane wave spectrum.
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