1. |
- Abramowicz, Marek A, 1945, et al.
(författare)
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No Observational Constraints from Hypothetical Collisions of Hypothetical Dark Halo Primordial Black Holes with Galactic Objects
- 2009
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 705:1, s. 659-669
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Tidskriftsartikel (refereegranskat)abstract
- It was suggested by several authors that hypothetical primordial black holes (PBHs) may contribute to the dark matter (DM) in our Galaxy. There are strong constraints based on the Hawking evaporation that practically exclude PBHs with masses m pbh ~ 1015to1016 g and smaller as significant contributors to the Galactic DM. Similarly, PBHs with masses greater than about 1026 g are practically excluded by the gravitational lensing observation. The mass range between 1016 g
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2. |
- Adamovic, Tatjana, 1974, et al.
(författare)
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Nonrandom pattern of chromosome aberrations in 17beta-estradiol-induced rat mammary tumors: indications of distinct pathways for tumor development.
- 2007
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Ingår i: Genes, chromosomes & cancer. - : Wiley. - 1045-2257 .- 1098-2264. ; 46:5, s. 459-69
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Tidskriftsartikel (refereegranskat)abstract
- Estrogens play an important role in breast cancer etiology and the ACI rat provides a novel animal model for defining the mechanisms through which estrogens contribute to mammary cancer development. In crossing experiments between the susceptible ACI strain and two resistant strains, COP (Copenhagen) and BN (Brown Norway), several quantitative trait loci (QTL) that affect development of 17beta-estradiol (E2)-induced mammary tumors have been defined. Using comparative genomic hybridization (CGH), we have analyzed cytogenetic aberrations in E2-induced mammary cancers and have found clear patterns of nonrandom chromosomal involvement. Approximately two thirds of the tumors exhibited copy number changes. Losses of rat chromosome 5 (RNO5) and RNO20 were particularly common, and it was found that these two aberrations often occurred together. A third recurrent aberration involving proximal gain and distal loss in RNO6 probably defined a distinct subgroup of tumors, since it never occurred in combination with RNO5 loss. Interestingly, QTL with powerful effects on mammary cancer development have been mapped to RNO5 and RNO6. These findings suggest that there were at least two genetic pathways to tumor formation in this rat model of E2-induced mammary cancer. By performing CGH on mammary tumors from ACI rats, F1 rats from crosses between the ACI and COP or BN strains and ACI.BN-Emca8 congenic rats, which carry the BN allele of the Emca8 QTL on RNO5 on the ACI genetic background, we were able to determine that the constitution of the germ line influences the pattern of chromosomal aberrations.
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3. |
- Allison, J, et al.
(författare)
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Geant4 developments and applications
- 2006
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Ingår i: IEEE TRANSACTIONS ON NUCLEAR SCIENCE. - 0018-9499. ; 53:1, s. 270-278
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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4. |
- Alström, Per, et al.
(författare)
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Phylogeny and classification of the Old World Emberizini (Aves, Passeriformes)
- 2008
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 47:3, s. 960-973
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Tidskriftsartikel (refereegranskat)abstract
- The phylogeny of the avian genus Emberiza and the monotypic genera Latoucheornis, Melophus and Miliaria (collectively the Old World Emberizini), as well as representatives for the New World Emberizini, the circumpolar genera Calcarius and Plectrophertax and the four other generally recognized tribes in the subfamily Emberizinae was estimated based on the mitochondrial cytochrome b gene and introns 6-7 of the nuclear ornithine decarboxylase (ODC) gene. Our results support monophyly of the Old World Emberizini, but do not corroborate a sister relationship to the New World Emberizini. Calcarius and Plectrophenax form a clade separated from the other Emberizini. This agrees with previous studies, and we recommend the use of the name Calcariini. Latoucheornis, Melophus and Miliaria are nested within Emberiza, and we therefore propose they be synonymized with Emberiza. Emberiza is divided into four main clades, whose relative positions are uncertain, although a sister relation between a clade with six African species and one comprising the rest of the species (30, all Palearctic) is most likely. Most clades agree with traditional, morphology-based, classifications. However, four sister relationships within Emberiza, three of which involve the previously recognized Latoucheornis, Melophus and Miliaria, are unpredicted, and reveal cases of strong morphological divergence. In contrast, the plumage similarity between adult male Emberiza (formerly Latoucheornis) siemsseni and the nominate subspecies of the New World Junco hyemalis is shown to be the result of parallel evolution. A further case of parallel plumage evolution, between African and Eurasian taxa, is pointed out. Two cases of discordance between the mitochondrial and nuclear data with respect to branch lengths and genetic divergences are considered to be the result of introgressive hybridization.
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5. |
- Anthony, Richard, et al.
(författare)
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Autonomic Middleware for Automotive Embedded Systems
- 2009
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Ingår i: Autonomic Communication. - Boston, MA : Springer US. - 9780387097527 ; , s. 169-210
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Bokkapitel (refereegranskat)abstract
- This chapter describes DySCAS: an advanced autonomic platform-independent middleware framework for automotive embedded systems. The concepts and architecture are motivated and described in detail, focusing on the need for, and achievement of, high flexibility and automatic run-time reconfiguration. The design of the middleware is positioned with respect to the way it overcomes the specific technical, environmental, and performance challenges of the automotive domain. Self-management is achieved in terms of automatic configuration for context-aware behavior, resource-use efficiency, and self-healing to handle run-time detected faults. The self-management is governed by the use of policies distributed throughout the middleware components. The simulation techniques that have been used for extensive validation are described and some key results presented. A reference implementation is presented, illustrating the way in which the various concepts and mechanisms can be realized and orchestrated.
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6. |
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7. |
- Baldock, Paul A., et al.
(författare)
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Novel role of Y1 receptors in the coordinated regulation of bone and energy homeostasis
- 2007
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Ingår i: Journal of Biological Chemistry. - 1083-351X .- 0021-9258. ; 282:26, s. 19092-19102
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Tidskriftsartikel (refereegranskat)abstract
- The importance of neuropeptide Y (NPY) and Y2 receptors in the regulation of bone and energy homeostasis has recently been demonstrated. However, the contributions of the other Y receptors are less clear. Here we show that Y1 receptors are expressed on osteoblastic cells. Moreover, bone and adipose tissue mass are elevated in Y1(-/-) mice with a generalized increase in bone formation on cortical and cancellous surfaces. Importantly, the inhibitory effects of NPY on bone marrow stromal cells in vitro are absent in cells derived from Y1(-/-) mice, indicating a direct action of NPY on bone cells via this Y receptor. Interestingly, in contrast to Y2 receptor or germ line Y1 receptor deletion, conditional deletion of hypothalamic Y1 receptors in adult mice did not alter bone homeostasis, food intake, or adiposity. Furthermore, deletion of both Y1 and Y2 receptors did not produce additive effects in bone or adiposity. Thus Y1 receptor pathways act powerfully to inhibit bone production and adiposity by nonhypothalamic pathways, with potentially direct effects on bone tissue through a single pathway with Y2 receptors.
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8. |
- Bao, Lei, et al.
(författare)
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A scheme for joint quantization, error protection and feedback control over noisy channels
- 2007
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Ingår i: 2007 AMERICAN CONTROL CONFERENCE, VOLS 1-13. - : IEEE. - 9781424409884 ; , s. 2456-2461
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Konferensbidrag (refereegranskat)abstract
- We study a closed-loop scalar control system with feedback transmitted over a discrete noisy channel. For this problem, we propose a joint design of the state measurement quantization, protection against channel errors, and control. The goal is to minimize a linear quadratic cost function over a finite horizon. In particular we focus on a special case where we verify that certainty equivalence holds, and for this case we design joint source-channel encoder and decoder/estimator pairs. The proposed algorithm leads to a practically feasible design of time-varying non-uniform quantization and control. Numerical results demonstrate the promising performance obtained by employing the proposed iterative optimization algorithm.
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9. |
- Bao, Lei, 1976-
(författare)
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Control over Low-Rate Noisy Channels
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Networked embedded control systems are present almost everywhere. A recent trendis to introduce radio communication in these systems to increase mobility and flex-ibility. Network nodes, such as the sensors, are often simple devices with limitedcomputing and transmission power and low storage capacity, so an important prob-lem concerns how to optimize the use of resources to provide sustained overall sys-tem performance. The approach to this problem taken in the thesis is to analyzeand design the communication and control application layers in an integrated man-ner. We focus in particular on cross-layer design techniques for closed-loop controlover non-ideal communication channels, motivated by future control systems withvery low-rate and highly quantized sensor communication over noisy links. Severalfundamental problems in the design of source–channel coding and optimal controlfor these systems are discussed.The thesis consists of three parts. The first and main part is devoted to the jointdesign of the coding and control for linear plants, whose state feedback is trans-mitted over a finite-rate noisy channel. The system performance is measured by afinite-horizon linear quadratic cost. We discuss equivalence and separation proper-ties of the system, and conclude that although certainty equivalence does not holdin general it can still be utilized, under certain conditions, to simplify the overalldesign by separating the estimation and the control problems. An iterative opti-mization algorithm for training the encoder–controller pairs, taking channel errorsinto account in the quantizer design, is proposed. Monte Carlo simulations demon-strate promising improvements in performance compared to traditional approaches.In the second part of the thesis, we study the rate allocation problem for statefeedback control of a linear plant over a noisy channel. Optimizing a time-varyingcommunication rate, subject to a maximum average-rate constraint, can be viewedas a method to overcome the limited bandwidth and energy resources and to achievebetter overall performance. The basic idea is to allow the sensor and the controllerto communicate with a higher data rate when it is required. One general obstacle ofoptimal rate allocation is that it often leads to a non-convex and non-linear problem.We deal with this challenge by using high-rate theory and Lagrange duality. It isshown that the proposed method gives a good performance compared to some otherrate allocation schemes.In the third part, encoder–controller design for Gaussian channels is addressed.Optimizing for the Gaussian channel increases the controller complexity substan-tially because the channel output alphabet is now infinite. We show that an efficientcontroller can be implemented using Hadamard techniques. Thereafter, we proposea practical controller that makes use of both soft and hard channel outputs.
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10. |
- Bao, Lei, et al.
(författare)
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Encoder-decoder design for event-triggered feedback control over bandlimited channels
- 2006
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Ingår i: 2006 American Control Conference. - : IEEE. - 1424402093 ; , s. 4183-4188
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Konferensbidrag (refereegranskat)abstract
- Bandwidth limitations and energy constraints set severe restrictions on the design of control systems that utilize wireless sensor and actuator networks. It is common in these systems that a sensor node needs not be continuously monitored, but communicates to the controller only at certain instances when it detects a disturbance event. In this paper, such a scenario is studied and particular emphasis is on efficient utilization of the shared communication resources. Encoder-decoder design for an event-based control system with the plant affected by pulse disturbances is considered. A new iterative procedure is proposed which can jointly optimize encoder-decoder pairs for a certainty equivalent controller. The goal is to minimize a design criterion, in particular, a linear quadratic cost over a finite horizon. The algorithm leads to a feasible design of time-varying non-uniform encoder-decoder pairs. Numerical results demonstrate significant improvements in performance compared to a system using uniform quantization.
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11. |
- Bao, Lei, et al.
(författare)
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On Iterative System Design and Separation in Control Over Noisy Channels
- 2008
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Ingår i: IFAC World Congress, Volume 17, Part 1. - : IFAC.
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Konferensbidrag (refereegranskat)abstract
- We study a closed-loop control system with feedback transmitted over a noisy discrete memoryless channel. We design encoder-controller pairs that jointly optimize the sensor measurement quantization, protection against channel errors, and control. The designgoal is to minimize an expected linear quadratic cost over a finite horizon. As a result of deriving optimality criteria for this problem, we present new results on the validity of theseparation principle subject to certain assumptions. More precisely, we show that the certainty equivalence controller is optimal when the encoder is optimal and has full side-information about the symbols received at the controller. We then use this result to formulate tractable design criteria in the general case. Finally, numerical experiments are carried out to demonstrate the performance obtained by various design methods.
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12. |
- Bao, Lei, et al.
(författare)
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On optimal system design for feedback control over noisy channels
- 2007
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Ingår i: 2007 IEEE INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY PROCEEDINGS, VOLS 1-7. - : IEEE. - 9781424413973 ; , s. 2486-2490
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Konferensbidrag (refereegranskat)abstract
- We study a closed-loop multivariable control system with sensor feedback transmitted over a discrete noisy channel. For this problem, we propose a joint design of the state measurement quantization, protection against channel errors, and control. The proposed algorithm leads to a practically feasible design of time-varying non-uniform encoding and control. Numerical results demonstrate the performance obtained by employing the proposed iterative optimization algorithm.
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13. |
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14. |
- Bao, Lei, et al.
(författare)
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Optimized Rate Allocation for State Estimation over Noisy Channels
- 2009
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Ingår i: 2009 IEEE INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY. - NEW YORK : IEEE. ; , s. 2684-2688
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Konferensbidrag (refereegranskat)abstract
- Optimal rate allocation in a networked control system with limited communication resources is instrumental to achieve satisfactory overall performance. In this paper, a practical rate allocation technique for state estimation in linear dynamic systems over a noisy channel is proposed. The method consists of two steps: (i) the overall distortion is expressed as a function of rates at all time instants by means of high-rate quantization theory, and (ii) a constrained optimization problem to minimize the overall distortion is solved by using Lagrange duality. Monte Carlo simulations illustrate the proposed scheme, which is shown to have good performance when compared to arbitrarily selected rate allocations.
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15. |
- Bao, Lei, et al.
(författare)
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Optimized rate allocation for state feedback control over noisy channels
- 2009
-
Ingår i: Decision and Control, 2009 held jointly with the 2009 28th Chinese Control Conference. CDC/CCC 2009. Proceedings of the 48th IEEE Conference on. - : IEEE. - 9781424438716 ; , s. 573-578
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Konferensbidrag (refereegranskat)abstract
- Optimal rate allocation in a networked control system with highly limited communication resources is instrumental to achieve satisfactory overall performance. In this paper, we propose a rate allocation technique for state feedback control in linear dynamic systems over a noisy channel. Our method consists of two steps: (i) the overall distortion is expressed as a function of rates at all time instants by means of high-rate quantization theory, and (ii) a constrained optimization problem to minimize the overall distortion is solved. We show that a non-uniform quantization is in general the best strategy for state feedback control over noisy channels. Monte Carlo simulations illustrate the proposed scheme, which is shown to have good performance compared to arbitrarily selected rate allocations.
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16. |
- Bao, Lei, et al.
(författare)
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Rate allocation for quantized control over noisy channels
- 2009
-
Ingår i: Final Proceedings of the 2009 7th International Symposium on Modeling and Optimization in Mobile, Ad Hoc and Wireless Networks. - 9781424449200 ; , s. 595-603
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Konferensbidrag (refereegranskat)abstract
- To achieve satisfactory overall performance, optimal rate allocation in a networked control system with highly limited communication resources is instrumental. In this paper, a rate allocation technique for state feedback control in linear dynamic systems over a noisy channel is proposed. The method consists of two steps: (i) the overall cost is expressed as a function of rates at all time instants by means of high-rate quantization theory, and (ii) a constrained optimization problem to minimize the overall distortion is solved. It is shown that a non-uniform quantization is in general the best strategy for state feedback control over noisy channels. Monte Carlo simulations illustrate the proposed scheme, which is shown to have good performance when compared to arbitrarily selected rate allocations.
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17. |
- Bao, Lei, 1976-
(författare)
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Source-channel coding for closed-loop control
- 2006
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Networked embedded control systems are present almost everywhere. A recent trend is to introduce wireless sensor networks in these systems, to take advantage of the added mobility and flexibility offered by wireless solutions. In such networks, the sensor observations are typically quantized and transmitted over noisy links. Concerning the problem of closed-loop control over such non-ideal communication channels, relatively few works have appeared so far. This thesis contributes to this field, by studying some fundamentally important problems in the design of joint source--channel coding and optimal control. The main part of the thesis is devoted to joint design of the coding and control for scalar linear plants, whose state feedbacks are transmitted over binary symmetric channels. The performance is measured by a finite-horizon linear quadratic cost function. The certainty equivalence property of the studied systems is utilized, since it simplifies the overall design by separating the estimation and the control problems. An iterative optimization algorithm for training the encoder--decoder pairs, taking channel errors into account in the quantizer design, is proposed. Monte Carlo simulations demonstrate promising improvements in performance compared to traditional approaches. Event-triggered control strategies are a promising solution to the problem of efficient utilization of communication resources. The basic idea is to let each control loop communicate only when necessary. Event-triggered and quantized control are combined for plants affected by rarely occurring disturbances. Numerical experiments show that it is possible to achieve good control performance with limited control actuation and sensor communication.
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18. |
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19. |
- Boonpangrak, Somchai, et al.
(författare)
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Molecularly emprinted polymer microspheres prepared by precipitation polymerization using a sacrificial covalent bond
- 2006
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Ingår i: Journal of Applied Polymer Science. - : Wiley. - 1097-4628 .- 0021-8995. ; 99:4, s. 1390-1398
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Tidskriftsartikel (refereegranskat)abstract
- Molecularly imprinted polymer microspheres were prepared by precipitation polymerization using a sacrificial covalent bond. In the present model, cholesteryl (4-vinyl)phenyl carbonate was used as a template monomer. The imprinted microspheres were prepared using ethylene glycol dimethacrylate (EDMA) and divinylbenzene (DVB) as crosslinker. The base-labile carbonate ester bond was easily hydrolyzed to leave imprinted cavities in the resulting polymers. Radioligand binding analysis, elemental analysis, and scanning electron microscopy were used to characterize the imprinted materials. Imprinted microspheres prepared from DVB crosslinker had larger and more defined spherical shape, and displayed better imprinting effect than did the EDMA-based microparticles. For comparison, imprinted bulk polymers were also prepared in the same reaction solvent as that used in precipitation polymerization. Elemental analysis results indicated that imprinted microspheres contained more template monomer units than bulk materials. The efficiency of template removal by hydrolysis treatment for microspheres was also higher than that for bulk polymers. For DVB-based polymers, imprinted microspheres displayed higher specific cholesterol uptake than did the corresponding bulk polymer. (c) 2005 Wiley Periodicals, Inc.
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20. |
- Boonpangrak, Somchai, et al.
(författare)
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Preparation of molecularly imprinted polymers using nitroxide-mediated living radical polymerization
- 2006
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Ingår i: Biosensors & Bioelectronics. - : Elsevier BV. - 1873-4235 .- 0956-5663. ; 22:3, s. 349-354
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Tidskriftsartikel (refereegranskat)abstract
- The use of molecularly imprinted polymers (MIPs) in chemical and bioanalytical applications has been gaining in interest in recent years. Compared to their biological receptor counterparts, MIP's are easy to prepare, have long shelf stability and can be used under a variety of harsh conditions. The majority of MIPs currently used are produced by traditional free radical polymerization. One drawback with the use of standard free radical initiators is that little control can be exerted over the chemical processes that form the final imprinted cavities. In this study we set out to investigate the application of controlled (living) free radical polymerization to the preparation of MIPs. This was exemplified by the synthesis of cholesterol-imprinted bulk polymers by nitroxide-mediated polymerization (NMP). A sacrificial covalent bond was employed to maintain imprinting fidelity at elevated temperature. Selective uptake of cholesterol from solutions in hexane was studied with imprinted polymers prepared under different conditions. The imprinted hydrolyzed MIP prepared by NMP displayed higher selective cholesterol binding than that prepared by a traditional radical polymerization. (c) 2006 Elsevier B.V. All rights reserved.
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21. |
- Brendle, Annika, et al.
(författare)
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Polymorphisms in predicted microRNA-binding sites in integrin genes and breast cancer ITGB4 as prognostic marker.
- 2008
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Ingår i: Carcinogenesis. - : Oxford University Press. - 0143-3334 .- 1460-2180. ; 29:7, s. 1394-1399
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Tidskriftsartikel (refereegranskat)abstract
- Integrins control the cell attachment to the extracellular matrix and play an important role in mediating cell proliferation, migration and survival. A number of important cancer-associated integrin genes can be regulated by microRNAs (miRNAs) that bind to their target sites in the 3' untranslated regions. We examined the effect of single-nucleotide polymorphisms (SNPs) in predicted miRNA target sites of six integrin genes (ITGA3, ITGA6, ITGAv, ITGB3, ITGB4 and ITGB5) on breast cancer (BC) risk and clinical outcome. Six SNPs were genotyped in 749 Swedish incident BC cases with detailed clinical data and up to 15 years of follow-up together with 1493 matched controls. We evaluated associations between genotypes and BC risk and clinical tumour characteristics. Survival probabilities were compared between different subgroups. As a novel finding, several SNPs seemed to associate with the hormone receptor status. The strongest association was observed between the A allele of the SNP rs743554 in the ITGB4 gene and oestrogen receptor-negative tumours [odds ratio 2.09, 95% confidence intervals (CIs) 1.19-3.67]. The same SNP was associated with survival. The A allele carriers had a worse survival compared with the wild-type genotype carriers (hazard ratio 2.11, 95% CIs 1.21-3.68). The poor survival was significantly associated with the aggressive tumour characteristics: high grade, lymph node metastasis and high stage. None of the SNPs was significantly associated with BC risk. As the ITGB4 SNP seems to influence tumour aggressiveness and survival, it may have prognostic value in the clinic.
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22. |
- Cai, Yangjian, et al.
(författare)
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Coherent and partially coherent dark hollow beams with rectangular symmetry and paraxial propagation properties
- 2006
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Ingår i: Journal of the Optical Society of America. B, Optical physics. - 0740-3224 .- 1520-8540. ; 23:7, s. 1398-1407
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Tidskriftsartikel (refereegranskat)abstract
- A theoretical model is proposed to describe coherent dark hollow beams (DHBs) with rectangular symmetry. The electric field of a coherent rectangular DHB is expressed as a superposition of a series of the electric field of a finite series of fundamental Gaussian beams. Analytical propagation formulas for a coherent rectangular DHB passing through paraxial optical systems are derived in a tensor form. Furthermore, for the more general case, we propose a theoretical model to describe a partially coherent rectangular DHB. Analytical propagation formulas for a partially coherent rectangular DHB passing through paraxial optical systems are derived. The beam propagation factor (M-2 factor) for both coherent and partially coherent rectangular DHBs are studied. Numerical examples are given by using the derived formulas. Our models and method provide an effective way to describe and treat the propagation of coherent and partially coherent rectangular DHBs.
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23. |
- Cai, Yangjian, et al.
(författare)
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Propagation of a hollow Gaussian beam through a paraxial misaligned optical system
- 2006
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Ingår i: Optics Communications. - : Elsevier BV. - 0030-4018 .- 1873-0310. ; 265:2, s. 607-615
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Tidskriftsartikel (refereegranskat)abstract
- Based on the generalized diffraction integral formula for treating the propagation of a laser beam through a paraxial misaligned optical system in the cylindrical coordinate system, we obtain an analytical formula for a hollow Gaussian beam passing through a paraxial misaligned optical system. Furthermore, we also obtain the approximate analytical formula for a hollow Gaussian beam passing through a paraxial circularly apertured misaligned optical system by expanding the hard aperture function into a finite sum of complex Gaussian functions. As a numerical example, the propagation properties a hollow Gaussian beam through a misaligned thin lens are studied numerically.
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24. |
- Cavdar, Cicek, 1977-, et al.
(författare)
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Holding-Time-Aware and Availability-Guaranteed Connection Provisioning in Optical WDM Mesh Networks
- 2007
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Ingår i: 2007 International Symposium on High Capacity Optical Networks and Enabling Technologies, HONET. - 9781424418282 ; , s. 243-249
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Konferensbidrag (refereegranskat)abstract
- In optical wavelength-division multiplexing (WDM) networks, the progress in new technologies is paving the road towards dynamic optical transport networks in which leasable circuits can be set up and released on a short-term basis while providing huge capacities to bandwidth-hungry applications. Since interruption of a high-speed optical connection means a huge loss of data information, such connections need to be protected against failures. On the other hand, the explosive growth of different traffic types such as data, voice and video requires differentiated services besides availability-guaranteed bandwidth. Therefore, future network carriers need to meet strict SLA (Service Level Agreement) guidelines, thus guaranteeing a level of service, as well as achieving efficient resource utilization. Unprotected, shared-path, and dedicated-path protection techniques can be used to meet the differentiated availability requirements. Recently, among the other Service Level Specifications (SLSs), many new applications are identified by a predictable or known-in-advance holding-time. So, for dynamic provisioning of availabitity-guaranteed connections in an optical mesh network, we investigate a new algorithm which exploits the knowledge of connection holding times to accomplish minimum backup capacity allocation as compared to the previous holding-time-unaware approach.
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25. |
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