| 41. |
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| 42. |
- Hedsten, Karin, 1964, et al.
(författare)
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MEMS-based VCSEL beam steering using replicated polymer diffractive lens
- 2008
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Ingår i: Sensors and Actuators, A: Physical. - : Elsevier BV. - 0924-4247 .- 1873-3069. ; 142:1, s. 336-345
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Tidskriftsartikel (refereegranskat)abstract
- Abstract. This paper describes a fully integrated micro-optical system, in which dynamic angular control of the beam from a VCSEL (vertical cavity surface emitting laser) is realized by laterally moving a collimat¬ing diffractive lens in the light path. The lens is mounted on a translatable silicon stage, which consists of a frame with an opening for the light to traverse the lens and electro-statically driven comb actuators, by which the lateral movement is achieved. Devices implementing both 1D and 2D scanning have been fabricated and evaluated. Integration of the lens onto the translatable silicon stage is done using a newly developed fabrication process based on hot embossing of an amorphous fluorocarbon polymer. This fabrication process relies on a reversed-order protocol, where the structuring of the optical element precedes the silicon microstructuring. Assembly and packaging of the VCSEL-MOEMS system, using LTCC (low temperature cofired ceramic) technique, is also demonstrated. Optical evaluation of the system and beam steering function shows significant beam deflection for a relatively low driving voltage (~70 V).
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| 43. |
- Hellström, Björn, 1959-, et al.
(författare)
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Acoustic Design Artifacts and Methods for Urban Soundscapes
- 2008
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Ingår i: The 15th International Congress on Sound and Vibration In: International Journal of Acoustics & Vibration. ; , s. 52-52
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Konferensbidrag (refereegranskat)abstract
- The research question is: “How to develop and apply acoustic artifacts and design methodologies for improving soundscapes in urban outdoor spaces?” In the project, this research question is limited to two specific types of urban outdoor spaces – city-park and city-square – and to two types of acoustic design artifacts. These are: I. Dynamic promotion of qualitative site specific sounds (e.g., the overall site specific sonic atmosphere, sounds from human activities, birds and fountains), which creates an improved soundscape. II. Sound-art installations, that creates delimited auditory sub-spaces within the park/square. The purpose and method is: 1. To provide two case-studies of artistic soundscape improvement, one in a noise polluted city-park and one in a city-square. The case-studies will serve as models for future applications of the new acoustic design artifacts. 2. To create and validate an innovative acoustic design methodology based on state-of-the-art real-time acoustic simulation tools integrated into the design process. The methodology will be validated in psychoacoustic listening experiments and field studies. 3. To determine the potential of the two acoustic design artifacts (I Dynamic promotion of qualitative site specific sounds, and II Sound-art installations) for providing pleasant and restorative soundscapes, in order to strengthening the social interaction as well as the spatial and aesthetical qualities in noise polluted city parks/squares. The present project beats a new track by combining acoustic design with sound art research, integrating methodologies based on real-time acoustic simulation and application of psychoacoustic methodology for validating simulations and for evaluating perceptual, emotional and behavioural effects on visitors to public open spaces. The ongoing research project, financed by the Swedish Research Council, is executed by the University College of Arts, Crafts and Design (Konstfack), Gösta Ekman Laboratory – Stockholm University and Karolinska Institutet and the Interactive Institute, all in Stockholm, Sweden.
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| 44. |
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| 45. |
- Herland, Anna, et al.
(författare)
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Synthesis of a regioregular zwitterionic conjugated oligoelectrolyte, usable as an optical probe for detection of amyloid fibril formation at acidic pH
- 2005
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 127:7, s. 2317-2323
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Tidskriftsartikel (refereegranskat)abstract
- Changes of the optical properties of conjugated polyelectrolytes have been utilized to monitor noncovalent interactions between biomolecules and the conjugated polyelectrolytes in sensor applications. A regioregular, zwitterionic conjugated oligoelectrolyte was synthesized in order to create a probe with a defined set of optical properties and hereby facilitate interpretation of biomolecule−oligoelectrolyte interactions. The synthesized oligoelectrolyte was used at acidic pH as a novel optical probe to detect amyloid fibril formation of bovine insulin and chicken lysozyme. Interaction of the probe with formed amyloid fibrils results in changes of the geometry and the electronic structure of the oligoelectrolyte chains, which were monitored with absorption and emission spectroscopy.
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| 46. |
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| 47. |
- Holmberg, Anna H, et al.
(författare)
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Risk factors for hip fractures in a middle-aged population: a study of 33,000 men and women.
- 2005
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Ingår i: Osteoporosis International. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 16:Sep22, s. 2185-2194
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Tidskriftsartikel (refereegranskat)abstract
- Knowledge about subjects who sustain hip fractures in middle age is poor. This study prospectively investigated risk factors for hip fracture in middle age and compared risk factors for cervical and trochanteric hip fractures. The Malmo Preventive Project consists of 22,444 men, mean age 44 years, and 10,902 women, mean age 50 years at inclusion. Baseline assessment included multiple examinations and lifestyle information. Follow-up was up to 16 years with regard to occurrence of fracture. One hundred thirty-five women had one low-energy hip fracture each, 93 of which were cervical and 42 trochanteric. One hundred sixty-three men had 166 hip fractures, of which 81 were cervical and 85 trochanteric. In the final Cox regression model for women, the risk factors with the strongest associations with hip fracture were diabetes (risk ratio (RR) 3.89, 95% confidence interval (CI) 1.69-8.93, p=0.001) and poor self-rated health (RR 1.74, 95% CI 1.22-2.48, p=0.002). A history of previous fracture (RR 4.76, 95%CI 2.74-8.26, p=0.0001) was also a significant risk factor. In men, diabetes had the strongest association with hip fracture (RR 6.13, 95%CI 3.19-11.8, p=0.001). Smoking (RR 2.20, 95%CI 1.54-3.15, p=0.001), high serum gamma-glutamyl transferase (RR 1.84, 95%CI 1.50-2.26, p=0.001), poor self-rated health (RR 1.49, 95%CI 1.06-2.10, p=0.02) and reported sleep disturbances (RR 1.52, 95%CI 1.03-2.27, p=0.04) were other significant risk factors. The strongest risk factor for hip fracture for both women and men in middle age was diabetes. Many risk factors were similar for men and women, although the risk ratio differed. The risk factor pattern for cervical versus trochanteric fractures differed in both men and women. The findings indicate that those suffering a hip fracture before the age of 75 have a shorter life expectancy, suggesting that hip fractures affect the less healthy segment of the population.
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| 48. |
- Holmkvist, Johan, et al.
(författare)
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Common variants in maturity-onset diabetes of the young genes and future risk of type 2 diabetes
- 2008
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Ingår i: Diabetes. - : American Diabetes Association. - 1939-327X .- 0012-1797. ; 57:6, s. 1738-1744
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE-Mutations in the hepatocyte nuclear factor (HNF)-1 alpha, HNF-4 alpha, glucokinase (GCK), and HNF-1 beta genes cause maturity-onset diabetes of the young (MODY), but it is not known whether common variants in these genes predict future type 2 diabetes. RESEARCH DESIGN AND METHODS-We tested 14 previously associated polymorphisms in HNF-1 alpha, HNF-4 alpha, GCK, and HNF-1 beta for association with type 2 diabetes-related traits and future risk of type 2 diabetes in 2,293 individuals from the Botnia study (Finland) and in 15,538 individuals from the Malmo Preventive Project (Sweden) with a total follow-up >360,000 years. RESULTS-The polymorphism rs1169288 in HNF-1 alpha strongly predicted future type 2 diabetes (hazard ratio [HR] 1.2, P = 0.0002). Also, SNPs rs4810424 and rs3212198 in HNF-4a nominally predicted future type 2 diabetes (HR 1.3 [95% CI 1.0-1.6], P = 0.03; and 1.1 [1.0-1.2], P = 0.04). The rs2144908 polymorphism in HNF-4 alpha was associated with elevated rate of hepatic glucose production during a hyperinsulinemic-euglycemic clamp (P = 0.03) but not with deterioration of insulin secretion over time. The SNP rs1799884 in the GCK promoter was associated with elevated fasting plasma glucose (fPG) concentrations that remained unchanged during the follow-up period (P = 0.4; SE 0.004 [-0.003-0.007]) but did not predict future type 2 diabetes (HR 0.9 [0.8 -1.0], P = 0.1). Polymorphisms in HNF-1 beta (transcription factor 2 [TCF2]) did not significantly influence insulin or glucose values nor did they predict future type 2 diabetes. CONCLUSIONS-In conclusion, genetic variation in both HNF-1 alpha and HNF-4 alpha predict future type 2 diabetes, whereas variation in the GCK promoter results in a sustained but subtle elevation of fPG that is not sufficient to increase risk for future type 2 diabetes.
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| 49. |
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| 50. |
- Johansson, Stefan, et al.
(författare)
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An OFDM Timing Synchronization ASIC
- 2000
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Ingår i: The 7th IEEE International Conference on Electronics, Circuits and Systems, ICECS 2000.. - 0780365429 ; 1, s. 324-327
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Konferensbidrag (refereegranskat)abstract
- In this paper an OFDM timing synchronization ASIC is presented. The proposed synchronization unit can be used in any OFDM system. The algorithm is based on the correlation introduced by the cyclic prefix, which is exploited in the time domain where the time offset is estimated. Although the algorithm is too complex to be implemented on today's most powerful standard DSP, a hardware architecture that is optimized for the algorithm is implemented with moderate complexity. The unit contains 32 kbit RAM and 3000 gates. At the sample rate of 25 Msamples/s the power consumption is 16 mW, which is small for such a complex algorithm
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