| 1. |
- Brittberg, Mats, 1953, et al.
(författare)
-
Autolog broskcellstransplantation. Smärtlindring och återställd ledfunktion är målet : Autologous cartilage cell transplantation. The goal is pain relief and restored joint function
- 1995
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Ingår i: Nordisk medicin. - 0029-1420. ; 110:12, s. 330-4
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Tidskriftsartikel (refereegranskat)abstract
- Chondral and osteochondral damage is a common result of trauma to the joints. The capacity of cartilage to heal such damage is poor, and repetitive wear on joint surfaces that do not heal results in impaired joint function, which can culminate in full blown arthrosis. Thus, it is important to improve our knowledge of cartilage regenerative potential, and develop methods to forestall progression to arthrosis by promoting the early healing of cartilage damage. Autologous cartilage cell transplantation may be a mean of healing cartilage damage. A method of cultivating autologous chondrocytes for transplantation in the treatment of isolated damage to articular cartilage of the knee is presented in the article.
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| 2. |
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| 3. |
- Brittberg, Mats, 1953, et al.
(författare)
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Rabbit articular cartilage defects treated with autologous cultured chondrocytes.
- 1996
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Ingår i: Clinical orthopaedics and related research. - 0009-921X. ; :326, s. 270-83
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Tidskriftsartikel (refereegranskat)abstract
- Adult New Zealand rabbits were used to transplant autologously harvested and in vitro cultured chondrocytes into patellar chondral lesions that had been made previously and were 3 mm in diameter, extending down to the calcified zone. Healing of the defects was assessed by gross examination, light microscope, and histological-histochemical scoring at 8, 12, and 52 weeks. Chondrocyte transplantation significantly increased the amount of newly formed repair tissue compared to the found in control knees in which the lesion was solely covered by a periosteal flap. In another experiment, carbon fiber pads seeded with chondrocytes were used as scaffolds, and repair significantly increased at both 12 and 52 weeks compared to knees in which scaffolds without chondrocytes were implanted. The histologic quality scores of the repair tissue were significantly better in all knees in which defects were treated with chondrocytes compared to knees treated with periosteum alone and better at 52 weeks compared to knees in which defects were treated with carbon scaffolds seeded with chondrocytes. The repair tissue, however, tended to incomplete the bonding to adjacent cartilage. This study shows that isolated autologous articular chondrocytes that have been expanded for 2 weeks in vitro can stimulate the healing phase of chondral lesions. A gradual maturation of the hyalinelike repair with a more pronounced columnarization was noted as late as 1 year after surgery.
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| 4. |
- Brittberg, Mats, 1953, et al.
(författare)
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Treatment of deep cartilage defects in the knee with autologous chondrocyte transplantation.
- 1994
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Ingår i: The New England journal of medicine. - 0028-4793. ; 331:14, s. 889-95
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND. Full-thickness defects of articular cartilage in the knee have a poor capacity for repair. They may progress to osteoarthritis and require total knee replacement. We performed autologous chondrocyte transplantation in 23 people with deep cartilage defects in the knee. METHODS. The patients ranged in age from 14 to 48 years and had full-thickness cartilage defects that ranged in size from 1.6 to 6.5 cm2. Healthy chondrocytes obtained from an uninvolved area of the injured knee during arthroscopy were isolated and cultured in the laboratory for 14 to 21 days. The cultured chondrocytes were then injected into the area of the defect. The defect was covered with a sutured periosteal flap taken from the proximal medial tibia. Evaluation included clinical examination according to explicit criteria and arthroscopic examination with a biopsy of the transplantation site. RESULTS. Patients were followed for 16 to 66 months (mean, 39). Initially, the transplants eliminated knee locking and reduced pain and swelling in all patients. After three months, arthroscopy showed that the transplants were level with the surrounding tissue and spongy when probed, with visible borders. A second arthroscopic examination showed that in many instances the transplants had the same macroscopic appearance as they had earlier but were firmer when probed and similar in appearance to the surrounding cartilage. Two years after transplantation, 14 of the 16 patients with femoral condylar transplants had good-to-excellent results. Two patients required a second operation because of severe central wear in the transplants, with locking and pain. A mean of 36 months after transplantation, the results were excellent or good in two of the seven patients with patellar transplants, fair in three, and poor in two; two patients required a second operation because of severe chondromalacia. Biopsies showed that 11 of the 15 femoral transplants and 1 of the 7 patellar transplants had the appearance of hyaline cartilage. CONCLUSION. Cultured autologous chondrocytes can be used to repair deep cartilage defects in the femorotibial articular surface of the knee joint.
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| 5. |
- Evans Axelsson, Susan, et al.
(författare)
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Targeting free prostate-specific antigen for in vivo imaging of prostate cancer using a monoclonal antibody specific for unique epitopes accessible on free prostate-specific antigen alone
- 2012
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Ingår i: Cancer Biotherapy and Radiopharmaceuticals. - : Mary Ann Liebert Inc. - 1084-9785 .- 1557-8852. ; 27:4, s. 243-251
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Tidskriftsartikel (refereegranskat)abstract
- This study investigated the feasibility of targeting the free, unbound forms of prostate-specific antigen (fPSA) for in vivo imaging of prostate adenocarcinomas (PCa), as PSA is produced and secreted at abundance during every clinical stage and grade of PCa, including castration-resistant disease. We injected 125I-labeled monoclonal antibody PSA30 (specific for an epitope uniquely accessible on fPSA alone) intravenously in male nude mice carrying subcutaneous xenografts of LNCaP tumors (n=36). Mice were sacrificed over a time course from 4 hours to 13 days after injecting 125I-labeled PSA30. Tissue uptake of 125I-PSA30 at 48 and 168 hours after intravenous injection was compared with two clinically used positron emission tomography radiopharmaceuticals, 18F-fluoro-deoxy-glucose (18F-FDG) or 18F-choline, in cryosections using Digital AutoRadiography (DAR) and also compared with immunohistochemical staining of PSA and histopathology. On DAR, the areas with high 125I-PSA30 uptake corresponded mainly to morphologically intact and PSA-producing LNCaP cells, but did not associate with the areas of high uptake of either 18F-FDG or 18F-choline. Biodistribution of 125I-PSA30 measured in dissected organs ex vivo during 4 to 312 hours after intravenous injection demonstrated maximum selective tumor uptake 24–48 hours after antibody injection. Our data showed selective uptake in vivo of a monoclonal antibody highly specific for fPSA in LNCaP cells. Hence, in vivo imaging of fPSA may be feasible with putative usefulness in disseminated PCa.
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| 6. |
- Johansson, Fredrik, 1983-
(författare)
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Microscopic Simulation of Pedestrian Traffic
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There has recently been a renewed interest in planning for pedestrian traffic, primarily in connection to public transport interchange stations, since these are important for public transport to constitute an attractive alternative to car usage. This thesis concerns microscopic simulation of pedestrian traffic, which is a promising tool for analyzing and predicting the traffic situation in a given pedestrian facility; particularly powerful when the traffic is congested. Important applications of microscopic simulation include comparison of possible infrastructure designs such as proposed interchange stations, and evaluations of various traffic management solutions, for example information systems.The purpose of this thesis is to advance the capabilities of pedestrian microsimulation toward a level at which it can be reliably applied for quantitative analysis by practitioners in the field. The work is based on an established microscopic model of pedestrian dynamics, the Social Force Model (sfm), and the advances are made in a number of different areas.To be able to evaluate and compare simulated traffic situations suitable performance measures are needed. A set of local performance measures are proposed that quantifies the local delay rate density and estimates the discomfort perceived by the pedestrians.The sfm is extended to include waiting pedestrians through the introduction of a waiting model, demonstrated to be stable and free from oscillations. The inclusion of waiting pedestrians in the model is critical for accurate modelling of public transport interchange stations, where large groups of waiting pedestrians may hinder passing pedestrians if the design of the station is poor.The relaxation time of the adaptation to the preferred velocity is an important parameter in force based models of pedestrian traffic since it affects several behaviors of the simulated pedestrians, two of which are linear acceleration and turning movements. A comparison of observations of accelerating pedestrians reported in the literature and new observations of turning pedestrians indicates that no value of the relaxation time can give model behavior consistent with both sets of observations. This indicates that modifications of the model is needed to accurately reproduce the observed behavior.An important input to simulations is the preferred speed of the simulated pedestrians. The common assumption that the preferred speed distribution at a location does not vary during the day is tested through observations of pedestrian traffic at Stockholm Central Station. The results demonstrate that the preferred speeds are lower in the afternoon than in the morning, implying that the preferred speed should be treated as a source of uncertainty when applying pedestrian microsimulation.Finally, a sensitivity analysis of a simulation of the lower hall of Stockholm Central Station is performed to find the most important sources of uncertainty in the model predictions, given the available data. The results indicate that the uncertainty related to calibration is the largest of the considered potential error sources.
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| 7. |
- Peterson, Lars, 1936, et al.
(författare)
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Two- to 9-year outcome after autologous chondrocyte transplantation of the knee.
- 2000
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Ingår i: Clinical orthopaedics and related research. - 0009-921X. ; :374, s. 212-34
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Tidskriftsartikel (refereegranskat)abstract
- Autologous cultured chondrocyte transplantation was introduced in Sweden in 1987 for the treatment of large (1.5-12.0 cm2) full thickness chondral defects of the knee. The clinical, arthroscopic, and histologic results from the first 101 patients treated using this technique are reported in this study. Patients were assessed retrospectively using three types of endpoints: patient and physician derived clinical rating scales (five validated and two new); arthroscopic assessment of cartilage fill, integration, and surface hardness; and standard histochemical techniques. Ninety-four patients with 2- to 9-years followup were evaluable. Good to excellent clinical results were seen in individual groups as follows: isolated femoral condyle (92%), multiple lesions (67%), osteochondritis dissecans (89%), patella (65%), and femoral condyle with anterior cruciate ligament repair (75%). Arthroscopic findings in 53 evaluated patients showed good repair tissue fill, good adherence to underlying bone, seamless integration with adjacent cartilage, and hardness close to that of the adjacent tissue. Hypertrophic response of the periosteum or graft or both was identified in 26 arthroscopies; seven were symptomatic and resolved after arthroscopic trimming. Graft failure occurred in seven (four of the first 23 and three of the next 78) patients. Histologic analysis of 37 biopsy specimens showed a correlation between hyalinelike tissue (hyaline matrix staining positive for Type II collagen and lacking a fibrous component) and good to excellent clinical results. The good clinical outcomes of autologous chondrocyte transplantation in this study are encouraging, and clinical trials are being done to assess the outcomes versus traditional fibrocartilage repair techniques.
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| 8. |
- Ruber, Roger, et al.
(författare)
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Accelerator development at the FREIA Laboratory
- 2021
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Ingår i: Journal of Instrumentation. - : Institute of Physics Publishing (IOPP). - 1748-0221. ; 16:7
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Tidskriftsartikel (refereegranskat)abstract
- The FREIA Laboratory at Uppsala University focuses on superconducting technology and accelerator development. It actively supports the development of the European Spallation Source, CERN, and MAX IV, among others. FREIA has developed test facilities for superconducting accelerator technology such as a double-cavity horizontal test cryostat, a vertical cryostat with a novel magnetic field compensation scheme, and a test stand for short cryomodules. Accelerating cavities have been tested in the horizontal cryostat, crab-cavities cavities in the vertical cryostat, and cryomodules for ESS on the cryomodule test stand. High power radio-frequency amplifier prototypes based on vacuum tube technology were developed for driving spoke cavities. Solid-state amplifiers and power combiners are under development for future projects. We present the status of the FREIA Laboratory complemented with results of recent projects and future prospects.
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| 9. |
- Ait Ali, Abderrahman, 1991-, et al.
(författare)
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A disaggregate bundle method for train timetabling problems
- 2020
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Ingår i: Journal of Rail Transport Planning & Management. - : Elsevier BV. - 2210-9706 .- 2210-9714. ; 16
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Tidskriftsartikel (refereegranskat)abstract
- The train timetabling problem (TTP) consists of finding a feasible timetable for a number of trains which minimises some objective function, e.g., sum of running times or deviations from ideal departure times. One solution approach is to solve the dual problem of the TTP using so-called bundle methods. This paper presents a new bundle method that uses disaggregate data, as opposed to the standard bundle method which in a certain sense relies on aggregate data. We compare the disaggregate and aggregate methods on realistic train timetabling scenarios from the Iron Ore line in Northern Sweden. Numerical results indicate that the proposed disaggregate method reaches better solutions faster than the standard aggregate approach.
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| 10. |
- Ait Ali, Abderrahman, 1991-
(författare)
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Methods for Capacity Allocation in Deregulated Railway Markets
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Faced with increasing challenges, railways around Europe have recently undergone major reforms aiming to improve the efficiency and competitiveness of the railway sector. New market structures such as vertical separation, deregulation and open access can allow for reduced public expenditures, increased market competition, and more efficient railway systems.However, these structures have introduced new challenges for managing infrastructure and operations. Railway capacity allocation, previously internally performed within monopolistic national companies, are now conferred to an infrastructure manager. The manager is responsible for transparent and efficient allocation of available capacity to the different (often competing) licensed railway undertakings.This thesis aims at developing a number of methods that can help allocate capacity in a deregulated (vertically separated) railway market. It focuses on efficiency in terms of social welfare, and transparency in terms of clarity and fairness. The work is concerned with successive allocation of capacity for publicly controlled and commercial traffic within a segmented railway market.The contributions include cost benefit analysis methods that allow public transport authorities to assess the social welfare of their traffic, and create efficient schedules. The thesis also describes a market-based transparent capacity allocation where infrastructure managers price commercial train paths to solve capacity conflicts with publicly controlled traffic. Additionally, solution methods are developed to help estimate passenger demand, which is a necessary input both for resolving conflicts, and for creating efficient timetables.Future capacity allocation in deregulated markets may include solution methods from this thesis. However, further experimentations are still required to address concerns such as data, legislation and acceptability. Moreover, future works can include prototyping and pilot projects on the proposed solutions, and investigating legal and digitalisation strategies to facilitate the implementation of such solutions.
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| 11. |
- Ait-Ali, Abderrahman, 1991-, et al.
(författare)
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Värdering av trafikinformationsnyttor i tågtrafiken (VTT) : slutrapport
- 2024
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Tågförseningar tillsammans med ökande efterfrågan leder till betydande sociala kostnader. Ett sätt att minska dessa kostnader är genom effektiv kommunikation av olika typer av trafikinformation till passagerare. Beroende på vilken/när information tas emot minskar passagerarnas beteendeanpassningar deras resekostnader, särskilt vid förseningar.Detta projekt syftar till att beräkna de samhällsekonomiska nyttor som sådan trafikinformation ger. Detta åstadkoms genom att utveckla en kvantitativ modell för att kvantifiera värdet av att kommunicera information till resenärerna vid tågförseningar.Genom att studera olika störningsscenarier i ett studiefall från Stockholmspendeltåg, ger studien insikter till infrastrukturförvaltaren om samhällsnytta av sådana informationssystem som en del av de stora infrastrukturinvesteringarna. Dessa insikter kan också hjälpa till att utforma effektivare informationsstrategier för att minska samhällsekonomiska kostnader för tågstörningar.
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| 12. |
- Andersson, Emma, 1983-, et al.
(författare)
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Improved Railway Timetable Robustness for Reduced Traffic Delays – a MILP approach
- 2015
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Ingår i: 6th International Conference on Railway Operations Modelling and Analysis, Tokyo, Mars 23-26, 2015..
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Konferensbidrag (refereegranskat)abstract
- Maintaining high on-time performance and at the same time having high capacity utilization is a challenge for several railway traffic systems. The system becomes sensitive to disturbances and delays are easily propagating in the network. One way to handle this problem is to create more robust timetables; timetables that can absorb delays and prevent them from propagating. This paper presents an optimization approach to reduce the propagating of delays with a more efficient margin allocation in the timetable. A Mixed Integer Linear Programming (MILP) model is proposed in which the existing margin time is re-allocated to increase the robustness for an existing timetable. The model re-allocates both runtime margin time and headway margin time to increase the robustness at specific delay sensitive points in a timetable. We illustrate the model’s applicability for a real-world case where an initial, feasible timetable is modified to create new timetables with increased robustness. These new timetables are then evaluated and compared to the initial timetable. We evaluate how the MILP approach affects the initial timetable structure and its capability to handle disturbances by exposing the initial and the modified timetables to some minor initial disturbances of the range 1 up to 7 minutes. The results show that it is possible to reduce the delays by re-allocating margin time, for example, the total delay at end station decreases with 28 % in our real-world example.
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| 13. |
- Andersson, Emma, 1983-, et al.
(författare)
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Increasing robustness at single-track lines using the indicator robustness in passing pointss
- 2023
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- When several trains are planned to use the same infrastructure resource, there is always a risk for spreading of delays, which can be hard to recover from. It is a challenge for the Infrastructure Manager to make timetables that accommodate as much traffic as possible, without causing bad on-time performance. Timetable planners are in need of quantitative indicators to assess timetable robustness and accurate methods for how to make the timetable more robust.In this paper we assess the robustness for single-track lines with non-periodic timetables. At single-track lines, trains use the line for running in both directions and the trains can only pass or overtake each other at passing loops. This makes the system more sensitive for delays. In this paper we present a robustness indicator which captures the dependencies between trains at a single-track line. The indicator can be used to illustrate weaknesses in a timetable and also to indicate where and how to insert more robustness. In a simulation study, we show that it is possible to improve the performance by making small timetable adjustments according the indicator, without increasing runtimes or capacity utilization.
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| 14. |
- Andersson, Emma, 1983-, et al.
(författare)
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Introducing a New Quantitative Measure of Railway Timetable Robustness Based on Critical Points
- 2013
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Ingår i: 5th International Seminar on Railway Operations Modelling and Analysis - RailCopenhagen 2013. - 9788773272466
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Konferensbidrag (refereegranskat)abstract
- The growing demand for railway capacity has led to high capacity consumption at times and a delay-sensitive network with insufficient robustness. The fundamental challenge is therefore to decide how to increase the robustness. To do so there is a need for accurate measures that return whether the timetable is robust or not and indicate where improvements should be made. Previously presented measures are useful when comparing different timetable candidates with respect to robustness, but less useful to decide where and how robustness should be inserted. In this paper, we focus on points where trains enter a line, or where trains are being overtaken, since we have observed that these points are critical for the robustness. The concept of critical points can be used in the practical timetabling process to identify weaknesses in a timetable and to provide suggestions for improvements. In order to quantitatively assess how crucial a critical point may be, we have defined the measure RCP (Robustness in Critical Points). A high RCP value is preferred, and it reflects a situation at which train dispatchers will have higher prospects of handling a conflict effectively. The number of critical points, the location pattern and the RCP values constitute an absolute value for the robustness of a certain train slot, as well as of a complete timetable. The concept of critical points and RCP can be seen as a contribution to the already defined robustness measures which combined can be used as guidelines for timetable constructors.
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| 15. |
- Andersson, Emma, et al.
(författare)
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Robustness in Swedish Railway Traffic Timetables
- 2011
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Ingår i: Railrome 2011.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A tendency seen for quite some time in the Swedish railway network is a growing demand for capacity which no longer can be accommodated. This causes congestion and delays, and the relationships between the trains and how they affect eachother are significantly harder to overview and analyse. Railway traffic timetables normally contain margins to make them robust, and enable trains to recover from certain delays. How effective these margins are, depends on their size and location as well as the frequency and magnitude of the disturbances that occur. Hence, it is important to include marigns so, that they can be used operationally to recover from a variety of disturbances and not restricted to a specific part of the line and/or the timetable. In a case study we compare the performance of a selection of passenger train services to the different prerequisites given by the timetable (e.g. available margins and their location, critical train dependencies). The study focuses on the Swedish Southern mainline between Stockholm and Malmö on which a wide variety of train services operate, e.g. freight trains, local and regional commuter train services as well as long-distance trains with different speed profiles. The analysis shows a clear mismatch between where margins are placed and where delays occur. We also believe that the most widely used performance measure, which is related to the delay when arriving at the final destination, might give rise to an unnecessarily high delay rate at intermediate stations.
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| 16. |
- Andersson, Emma V.
(författare)
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Assessment of Robustness in Railway Traffic Timetables
- 2014
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A tendency seen for the last decades in many European railway networks is a growing demand for capacity. An increased number of operating trains has led to a delay sensitive system where it is hard to recover from delays, where even relatively small delays are easily propagating to other traffic.The overall aim of this thesis is to analyse the robustness of railway traffic timetables; why delays are propagating in the network and how the timetable design and dispatching strategies influence the delays. In this context we want to establish quantitative measures of timetable robustness. There is a need for measures that can be used by the timetable constructors. Measures that identify where and how to improve the robustness and thereby indicating how and where margin time should be inserted. It is also important that the measures can capture interdependencies between different trains.In this thesis we introduce the concept of critical points, which is a practical approach to identify robustness weaknesses in a timetable. In contrast to other measures, critical points can be used to identify specific locations in both time and space. The corresponding measure, Robustness in Critical Points (RCP) provides the timetable constructors with concrete suggestions for which trains that should be given more runtime or headway margin. The measure also identifies where the margin time should be allocated to achieve a higher robustness.In a case study we show that the delay propagation is highly related to the operational train dispatching. This study shows that the current prioritisation rule used in Sweden results in an economic inefficiency and therefore should be revised. This statement is further supported by RCP and the importance of giving the train dispatchers more flexibility to efficiently solve conflict situations.
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| 17. |
- Andersson, Emma V., 1983-, et al.
(författare)
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Quantifying railway timetable robustness in critical points
- 2013
-
Ingår i: Journal of Rail Transport Planning and Management. - : Elsevier. - 2210-9706 .- 2210-9714. ; 3:3, s. 95-110
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Tidskriftsartikel (refereegranskat)abstract
- Several European railway traffic networks experience high capacity consumption during large parts of the day resulting in delay-sensitive traffic system with insufficient robustness. One fundamental challenge is therefore to assess the robustness and find strategies to decrease the sensitivity to disruptions. Accurate robustness measures are needed to determine if a timetable is sufficiently robust and suggest where improvements should be made.Existing robustness measures are useful when comparing different timetables with respect to robustness. They are, however, not as useful for suggesting precisely where and how robustness should be increased. In this paper, we propose a new robustness measure that incorporates the concept of critical points. This concept can be used in the practical timetabling process to find weaknesses in a timetable and to provide suggestions for improvements. In order to quantitatively assess how crucial a critical point may be, we have defined the measure robustness in critical points (RCP). In this paper, we present results from an experimental study where a benchmark of several measures as well as RCP has been done. The results demonstrate the relevance of the concept of critical points and RCP, and how it contributes to the set of already defined robustness measures
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| 18. |
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| 19. |
- Attié, David, et al.
(författare)
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A time projection chamber with GEM-based readout
- 2017
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Ingår i: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - : Elsevier BV. - 0168-9002. ; 856, s. 109-118
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Tidskriftsartikel (refereegranskat)abstract
- For the International Large Detector concept at the planned International Linear Collider, the use of time projection chambers (TPC) with micro-pattern gas detector readout as the main tracking detector is investigated. In this paper, results from a prototype TPC, placed in a 1. T solenoidal field and read out with three independent Gas Electron Multiplier (GEM) based readout modules, are reported. The TPC was exposed to a 6. GeV electron beam at the DESY II synchrotron. The efficiency for reconstructing hits, the measurement of the drift velocity, the space point resolution and the control of field inhomogeneities are presented.
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| 20. |
- Axholt, Magnus, et al.
(författare)
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Optical See-Through Head Mounted Display : Direct Linear Transformation Calibration Robustness in the Presence of User Alignment Noise
- 2010
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Ingår i: Proceedings of the 54th Annual Meeting of the Human Factors and Ergonomics Society. - Linköping : Linköping University Electronic Press. - 9780945289371
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Konferensbidrag (refereegranskat)abstract
- The correct spatial registration between virtual and real objects in optical see-through augmented reality implies accurate estimates of the user’s eyepoint relative to the location and orientation of the display surface. A common approach is to estimate the display parameters through a calibration procedure involving a subjective alignment exercise. Human postural sway and targeting precision contribute to imprecise alignments, which in turn adversely affect the display parameter estimation resulting in registration errors between virtual and real objects. The technique commonly used has its origin incomputer vision, and calibrates stationary cameras using hundreds of correspondence points collected instantaneously in one video frame where precision is limited only by pixel quantization and image blur. Subsequently the input noise level is several order of magnitudes greater when a human operator manually collects correspondence points one by one. This paper investigates the effect of human alignment noise on view parameter estimation in an optical see-through head mounted display to determine how well astandard camera calibration method performs at greater noise levels than documented in computer vision literature. Through Monte-Carlo simulations we show that it is particularly difficult to estimate the user’s eyepoint in depth, but that a greater distribution of correspondence points in depth help mitigate the effects of human alignment noise.
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| 21. |
- Berbyuk, Viktor, 1953, et al.
(författare)
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Energy-optimal control of bipedal locomtion systems
- 2002
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Ingår i: J. Stability and Control: Theory and Application, (SACTA).. - 1563-3276. ; 4:2, s. 74-89
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Tidskriftsartikel (refereegranskat)abstract
- The mathematical statement of the problem of energy-optimal control for a bipedal locomotion system is given. The proposed statement of the problem is characterized by broad utilization of experimental data of normal human locomotion. It is done mainly by means of the mathematical formulation of the constraints imposed both on the phase coordinates and on the controlling stimuli of a system. A numerical method for the solution of optimal control problems for highly nonlinear and complex bipedal locomotion systems is proposed. The method is based on a special procedure of converting the initial optimal control problem into a standard nonlinear programming problem. This is made by an approximation of the independent variable functions using smoothing cubic splines and by the solution of inverse dynamics problem. The key features of the method are its high numerical effectiveness and the possibility to satisfy a lot of restrictions imposed on the phase coordinates of the system automatically and accurately. The proposed method is illustrated by computer simulation of the energy-optimal anthropomorphic motion of the bipedal walking robot over a horizontal surface.
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| 22. |
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| 23. |
- Berbyuk, Viktor, 1953, et al.
(författare)
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Modeling an design of robotic systems having spring-damper actuators
- 2000
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Ingår i: Proceedings of the 7th Mechatronics Forum International Conference, 6-8 September 2000, Atlanta, Georgia, USA, PERGAMON, 2000.. - 0080437036
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The role of inherent dynamics for the improvement of control strategies of robotic systems is studied. A mathematical formulation of the optimal control problem that is suitable for this investigation is proposed. In solving this problem closed-form expressions have been obtained for the optimal control strategies for n degrees-of-freedom robotic systems with passive (unpowered) drives and no restrictions upon their controlling stimuli, and with non-linear viscoelastic spring-damper actuators. The obtained results can be used in designing optimal spring-damper-like passive drives for robotic systems.
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| 24. |
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| 25. |
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| 26. |
- Berbyuk, Viktor, 1953, et al.
(författare)
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Optimization of control laws of the bipedal locomotion systems
- 1999
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Ingår i: In Advances in Computational Multibody Dynamics, Jorge A.C. Ambrósio and Werner O. Schiehlen (Eds.), IDMEC/IST, Lisbon, Portugal, September 20-23, 1999. ; , s. 713-728
-
Konferensbidrag (refereegranskat)abstract
- The mathematical statement of the problem of energy-optimal control for a bipedal locomotion system is given. The proposed statement of the problem is characterized by broad utilization of experimental data of normal human locomotion. It is done mainly by means of the mathematical formulation of the constraints imposed both on the phase coordinates and on the controlling stimuli of a system. A numerical method for the solution of the optimal control problems for highly nonlinear and complex bipedal locomotion systems is proposed. The method is based on a special procedure of converting the initial optimal control problem into a standard nonlinear programming problem. This is made by an approximation of the independent variable functions using smoothing cubic splines and by the solution of an inverse dynamics problem. The key features of the method are its high numerical effectiveness and the possibility to satisfy a lot of restrictions imposed on the phase coordinates of the system automatically and accurately. The proposed method is illustrated by computer simulation of the energy-optimal anthropomorphic motion of the bipedal walking robot over a horizontal surface.
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| 27. |
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| 28. |
- Björgvinsson, Erling, et al.
(författare)
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Prototyping Futures
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Prototyping Futures gives you a glimpse of what collaborating with academia might look like. Medea and its co-partners share their stories about activities happening at the research centre – projects, methods, tools, and approaches – what challenges lie ahead, and how these can be tackled. Examples of highlighted topics include: What is a living lab and how does it work? What are the visions behind the Connectivity Lab at Medea? And, how can prototyping-methods be used when sketching scenarios for sustainable futures? Other topics are: What is the role of the body when designing technology? What is collaborative media and how can this concept help us understand contemporary media practices? Prototyping Futures also discusses the open-hardware platform Arduino, and the concepts of open data and the Internet of Things, raising questions on how digital media and connected devices can contribute to more sustainable lifestyles, and a better world.
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| 29. |
- Boström, Anders E, 1951, et al.
(författare)
-
Scattering of acoustic waves by a circular disc in the interface between two fluids
- 1991
-
Ingår i: Journal of the Acoustical Society of America. - 1520-8524 .- 0001-4966. ; 90, s. 3338-3343
-
Tidskriftsartikel (refereegranskat)abstract
- The scattering of acoustic waves by a sound-hard circular disc situated in the planar interface between two different fluids is considered. The incident wave is taken as a plane wave and a Hankel transform representation of the scattered field is used. After some manipulations using the boundary conditions, this leads to an integral equation over the disc for the potential jump across the disc. This jump is expanded in a series of Legendre functions which fulfill the correct edge condition and the integral equation is projected on the same set of Legendre functions. The far fields are calculated and the implications of energy conservation are explored and used as a numerical check. A few numerical computations showing the disc-scattered far field amplitude and the total scattering cross section are given and are shown to compare favorably with the expectations from simple ray theory at higher frequencies.
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| 30. |
- Breyer, Nils, et al.
(författare)
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Attraktivare tågresor med byten genom trafikinformation om anslutningssäkerheten
- 2024
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Ingår i: Sammanställning av referat från Transportforum 2024. - Linköping : Statens väg- och transportforskningsinstitut. ; , s. 114-115
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Resenärer upplever byten som oattraktiva vilket leder till att färre väljer att resa kollektivt om resan kräver byten. Färdmedelsvalet påverkas inte bara av den faktiska tiden som krävs för bytet, utan resenärer upplever också ytterligare ett bytesmotstånd på mellan 5 och 13 minuter eftersom varje byte tillför osäkerhet och komplexitet till resan. Ett sätt att minska bytesmotsståndet är att under resans gång tillhandahålla resenärer bättre information om kommande byten. Vi har därför belyst följande frågeställningar: Hur kan anslutningssäkerheten mellan tåg analyseras baserad på historiska data?Hur kan anslutningssäkerheten mellan tåg skattas utifrån aktuell trafiksituation?På vilket sätt kan anslutningssäkerheten och annan relevant information kommuniceras till resenären för att underlätta resor med byten?Vi definierar en potentiell anslutning som ett par av tåg a och b, där den planerade avgången för tåg b är mellan 3 och 60 minuter efter den planerade ankomsten av tåg a. Anslutningssäkerheten mellan tågen är sannolikheten att det utifrån den faktiska ankomsten för tåg a går att nå den faktiska avgången för tåg b. Vi använder flera månaders historisk tågtrafikinformation om tågens ankomst- och avgångstider för att analysera faktorer som påverkar anslutnigssäkerheten. För att få en uppfattning i realtid om en kommande anslutningen nås kan resenärer idag titta på de beräknade tider för tågen som kommuniceras till resenärer i händelse av förseningar. Dessa tider kan dock vara svåra att leta fram, ändras ofta i efterhand och osäkerheten är okänd för resenärerna. Vi presenterar i stället modeller som i realtid uppskattar anslutningssäkerheten för ett specifikt byte som en resenär ska göra. Modeller använder sig dels av historiska utfall, dels av aktuella trafikinformationsdata. Genom att dela upp datasetet i tränings- och valideringsperioder utvärderas den modellerna för att beräkna anslutningssäkerheten.Vi använder Alvesta station som fallstudie. Stationen är en viktig nod i Sverige där Södra stambanan och den enkelspåriga linjen Göteborg - Kalmar möts. Totalt innehåller datasetet 16413 passagerartåg och 60619 potentiella anslutningar. Analysen av denna historiska data visar att anslutningssäkerheten generellt minskar under dagen och är särskilt låg på kvällen. En första trädbaserad modell indikerar även att anslutningar från fjärrtåg är mer osäkra då dessa tåg i högre grad är försenade.
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| 31. |
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| 32. |
- Brittberg, Mats, 1953, et al.
(författare)
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Autologous chondrocytes used for articular cartilage repair: an update.
- 2001
-
Ingår i: Clinical orthopaedics and related research. - 0009-921X. ; :391 Suppl
-
Forskningsöversikt (refereegranskat)abstract
- Articular cartilage in adults has a poor ability to self-repair after a substantial injury; however, it is not known whether there is a cartilage resurfacing technique superior to the existing techniques. It is not satisfactory that at the beginning of the new millennium, there still is a lack of randomized studies comparing different cartilage repair techniques and there still is little knowledge of the natural course of a cartilaginous lesion. To date, various articular cartilage resurfacing techniques have the potential to improve the repair of cartilage defects and reduce the patient's disability. One such cartilage repair technique is autologous chondrocyte transplantation combined with a periosteal graft. Since the first patient was operated on in 1987, much interest in cartilage repair and cell engineering has emerged. The experience with autologous chondrocyte transplantation during the past 13 years with in vitro chondrocyte expansion, cartilage harvest, and postoperative biopsy technique is discussed, and the latest followup of 213 consecutive patients in different subgroups with 2 to 10 years followup is presented. The technique gives stable long-term results with a high percentage of good to excellent results (84%-90%) in patients with different types of single femoral condyle lesions, whereas patients with other types of lesions have a lower degree of success (mean, 74%).
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| 33. |
- Brittberg, Mats, 1953, et al.
(författare)
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Clonal growth of human articular cartilage and the functional role of the periosteum in chondrogenesis.
- 2005
-
Ingår i: Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society. - : Elsevier BV. - 1063-4584. ; 13:2, s. 146-53
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Clinical cartilage repair with transplantation of cultured chondrocytes, the first described technique introduced in 1994, includes a periosteal membrane but today cells are also implanted without the periosteal combination. The aim of this study was to see if the periosteum had more than a biomechanical function and if the periosteum had a biological effect on the seeded cells tested in an agarose system in which the clonal growth in agarose and the external growth stimulation could be analysed. METHODS: Four different experiments were used to study the growth of human chondrocytes in agarose and the periosteal influence. Human chondrocytes were isolated and transferred to either primary or secondary agarose culture. After 4 weeks, the total number of clones >50 microm was counted. Cocultures of chondrocytes and periosteal tissue, cultures of chondrocytes with conditioned medium from chondrocytes, periosteal cells and fibroblast were used to study a potential stimulatory effect on growth and different cytokines and growth factors were analysed. RESULTS: It was found that the human chondrocytes had different growth properties in agarose with the formation of four different types of clones: a homogenous clone without matrix production, a homogenous clone with matrix production, a differentiated clone with matrix production and finally a differentiated clone without matrix production. The periosteum exerted a paracrine effect on cultured chondrocytes in agarose resulting in a higher degree of cloning. The chondrocytes produced significant amounts of interleukin (IL)-6, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF) and transforming growth factor (TGF)-beta. The periosteum produced significant amounts of IL-6, IL-8 and TGF-beta. Cocultures of chondrocytes and periosteum demonstrated a potentiation of IL-6 and IL-8 release but not of TGF-beta and GM-CSF. CONCLUSION: Articular chondrocytes are able to form clones of different properties in agarose and the periosteum has a capacity of stimulating chondrocyte clonal growth and differentiation and secretes significant amounts of IL-6, IL-8, GM-CSF and TGF-beta. It may be that the repair of cartilage defects with seeded chondrocytes could benefit from the combination with a periosteal graft. The production of TGF-beta by implanted chondrocytes could influence the chondrogenic cells in the periosteum to start a periosteal chondrogenesis and together with the matrix from implanted chondrocyte production, a repair of cartilaginous appearance may develop; a dual chondrogenic response is possible.
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| 34. |
- Carey, J. L., et al.
(författare)
-
Autologous Chondrocyte Implantation as Treatment for Unsalvageable Osteochondritis Dissecans: 10- to 25-Year Follow-up
- 2020
-
Ingår i: American Journal of Sports Medicine. - : SAGE Publications. - 0363-5465 .- 1552-3365. ; 48:5, s. 1134-1140
-
Tidskriftsartikel (refereegranskat)abstract
- Background: An unsalvageable osteochondritis dissecans (OCD) fragment has been defined as one that cannot be saved. Unsalvageable OCD lesions have been treated with various techniques, including fragment excision, microfracture, osteochondral autograft transfer, fresh osteochondral allograft transplantation, and autologous chondrocyte implantation (ACI). Hypothesis: Patients who underwent ACI as treatment for unsalvageable OCD more than 10 years ago would maintain satisfactory patient-oriented outcome measures and have a low need for additional open surgery, especially arthroplasty. Study Design: Case series; Level of evidence, 4. Methods: All Swedish and Norwegian patients (59 patients with 67 OCD lesions) who underwent ACI for OCD under the direction of the senior author between 1990 and 2005 were identified through manual chart review. Features of the patient, OCD lesion, and surgery were extracted from the medical record and intraoperative photographs. Patients were sent questionnaires to assess the Knee injury and Osteoarthritis Outcome Score, Tegner-Wallgren activity score, and Lysholm score. In addition, patients were asked whether they had to undergo further surgery, including knee replacement, of the knee that underwent ACI. They were asked whether they would have the surgery again if in the same situation. Results: A total of 55 patients (93%) with 61 OCD lesions (91%) responded. The median follow-up duration was 19 years (range, 10-26 years) and the median age at follow-up was 43 years (range, 28-69 years). Subsequent arthroscopy was performed in the majority of cases, although many of these were scheduled “second looks” as part of a study. With respect to other subsequent surgery, 12 knees (20%) underwent any additional open surgery, but only 2 knees (3%) underwent arthroplasty. Eight knees (13%) underwent revision ACI. Most patients reached their preinjury activity level (62%) and would undergo ACI again if in the same situation (85%). If failure is defined as revision of the graft or conversion to arthroplasty, then survivorship after ACI for OCD in the current study would be 87% at 10 years, 85% at 15 years, and 82% at 20 years. Conclusion: ACI for OCD provides a durable treatment option. At a median follow-up of 19 years, there was a very low (~3%) conversion to total knee arthroplasty. © 2020 The Author(s).
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| 35. |
- Carlander, Anders, 1979, et al.
(författare)
-
Choices of savings options related to trust in banks’ competence, benevolence and stability
- 2013
-
Ingår i: Journal of Financial Services Marketing. - : Springer Science and Business Media LLC. - 1363-0539 .- 1479-1846. ; 18:2, s. 121-136
-
Tidskriftsartikel (refereegranskat)abstract
- The study investigates whether beliefs in professional investor skill in conjunction with trust in banks and other fund managers explain choices of options for long-term savings. From questionnaire data obtained for a population-based sample (n=178) and a sample of undergraduates (n=186), two index measures were constructed, one of beliefs in the skill of professional investors and another of trust in fund managers. The trust index was aggregated for the three interrelated components: competence, benevolence and stability. Regression analyses of the likelihood of savings in an actively managed fund showed an expected effect of investor-skill beliefs that was mediated by trust in the fund manager. In addition, self-reported knowledge played a larger role than trust for choices of passively managed index funds and in particular for own investment in stocks.
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| 36. |
- Carlsson, Anders, et al.
(författare)
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Molecular serum portraits in patients with primary breast cancer predict the development of distant metastases.
- 2011
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Ingår i: Proceedings of the National Academy of Sciences. - : Proceedings of the National Academy of Sciences. - 1091-6490 .- 0027-8424. ; 108:34, s. 14252-14257
-
Tidskriftsartikel (refereegranskat)abstract
- The risk of distant recurrence in breast cancer patients is difficult to assess with current clinical and histopathological parameters, and no validated serum biomarkers currently exist. Using a recently developed recombinant antibody microarray platform containing 135 antibodies against 65 mainly immunoregulatory proteins, we screened 240 sera from 64 patients with primary breast cancer. This unique longitudinal sample material was collected from each patient between 0 and 36 mo after the primary operation. The velocity for each serum protein was determined by comparing the samples collected at the primary operation and then 3-6 mo later. A 21-protein signature was identified, using leave-one-out cross-validation together with a backward elimination strategy in a training cohort. This signature was tested and evaluated subsequently in an independent test cohort (prevalidation). The risk of developing distant recurrence after primary operation could be assessed for each patient, using her molecular portraits. The results from this prevalidation study showed that patients could be classified into high- versus low-risk groups for developing metastatic breast cancer with a receiver operating characteristic area under the curve of 0.85. This risk assessment was not dependent on the type of adjuvant therapy received by the patients. Even more importantly, we demonstrated that this protein signature provided an added value compared with conventional clinical parameters. Consequently, we present here a candidate serum biomarker signature able to classify patients with primary breast cancer according to their risk of developing distant recurrence, with an accuracy outperforming current procedures.
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| 37. |
- Cossarizza, A., et al.
(författare)
-
Guidelines for the use of flow cytometry and cell sorting in immunological studies (second edition)
- 2019
-
Ingår i: European Journal of Immunology. - : Wiley. - 0014-2980 .- 1521-4141. ; 49:10, s. 1457-1973
-
Tidskriftsartikel (refereegranskat)abstract
- These guidelines are a consensus work of a considerable number of members of the immunology and flow cytometry community. They provide the theory and key practical aspects of flow cytometry enabling immunologists to avoid the common errors that often undermine immunological data. Notably, there are comprehensive sections of all major immune cell types with helpful Tables detailing phenotypes in murine and human cells. The latest flow cytometry techniques and applications are also described, featuring examples of the data that can be generated and, importantly, how the data can be analysed. Furthermore, there are sections detailing tips, tricks and pitfalls to avoid, all written and peer-reviewed by leading experts in the field, making this an essential research companion.
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| 38. |
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| 39. |
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| 40. |
- De Beeck, Michiel Op, et al.
(författare)
-
Elucidating fungal decomposition of organic matter at sub-micrometer spatial scales using optical photothermal infrared (O-PTIR) microspectroscopy
- 2024
-
Ingår i: Applied and Environmental Microbiology. - 0099-2240. ; 90:2
-
Tidskriftsartikel (refereegranskat)abstract
- In microbiological studies, a common goal is to link environmental factors to microbial activities. Both environmental factors and microbial activities are typically derived from bulk samples. It is becoming increasingly clear that such bulk environmental parameters poorly represent the microscale environments microorganisms experience. Using infrared (IR) microspectroscopy, the spatial distribution of chemical compound classes can be visualized, making it a useful tool for studying the interactions between microbial cells and their microenvironments. The spatial resolution of conventional IR microspectroscopy has been limited by the diffractionlimit of IR light. The recent development of optical photothermal infrared (O-PTIR) microspectroscopy has pushed the spatial resolution of IR microspectroscopy beyond this diffractionlimit, allowing the distribution of chemical compound classes to be visualized at sub-micrometer spatial scales. To examine the potential and limitations of O-PTIR microspectroscopy to probe the interactions between fungal cells and their immediate environments, we imaged the decomposition of cellulose filmsby cells of the ectomycorrhizal fungus Paxillus involutus and compared O-PTIR results using conventional IR microspectroscopy. Whereas the data collected with conventional IR microspectroscopy indicated that P. involutus has only a very limited ability to decompose cellulose films,O-PTIR data suggested that the ability of P. involutus to decompose cellulose was substantial. Moreover, the O-PTIR method enabled the identificationof a zone located outside the fungal hyphae where the cellulose was decomposed by oxidation. We conclude that O-PTIR can provide valuable new insights into the abilities and mechanisms by which microorganisms interact with their surrounding environments.
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| 41. |
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| 42. |
- Erlandson, William, et al.
(författare)
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Meta-Heuristic for inserting a robust train path in a non-cyclic timetable
- 2023
-
Ingår i: Transportation planning and technology (Print). - : TAYLOR & FRANCIS LTD. - 0308-1060 .- 1029-0354. ; 46:7, s. 842-863
-
Tidskriftsartikel (refereegranskat)abstract
- Many freight trains depart Swedish marshalling yards before or after their planned departure times. Today, a deviating departure time is allowed if no conflicting train path can be found a few stations ahead. This increases the risk that the train might be delayed to its destination and cause delays to other trains. We present a meta-heuristic that modifies a timetable by adding a train path (for our freight train) and, if necessary, adjusting surrounding train paths. The aim of the insertion of the additional train path and the adjustments of the existing ones is to obtain a large bottleneck robustness, that is, the largest possible minimal temporal distance to any other train in the timetable. We provide experimental results for a Swedish railway stretch with a non-cyclic timetable and heterogeneous traffic. We show that we quickly add a train path, while improving the robustness of the timetable.
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| 43. |
- Fornstedt, Torgny, et al.
(författare)
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HPLC vs UHPLC - a comparison of peak asymmetry and plan to step forward using Quality by Design (QbD) related to analytical methods
- 2012
-
Konferensbidrag (refereegranskat)abstract
- The purpose of this study is to demonstrate, with experiments and with computer simulations based on a firm chromatographic theory, that the wide spread perception of that the United States Pharmacopeia tailing factor must be lower than 2 (Tf < 2) is questionable when using the latest generation of LC equipment. It is shown that highly efficient LC separations like those obtained with sub-2 ïm porous and 2.7 ïm superficially porous particles (UHPLC) produce significantly higher Tf-values than the corresponding separation based on 3 ïm porous particles (HPLC) when the same amount of sample is injected. Still UHPLC separations provide a better resolution to adjacent peaks. Expressions have been derived that describe how the Tf-value changes with particle size or number of theoretical plates. Expressions have also been derived that can be used to scale the injection volume based on particle size or number of theoretical plates to maintain the Tf-value when translating a HPLC separation to the corresponding UHPLC separation. This aspect has been ignored in previous publications. Finally, data obtained from columns with different age/condition indicate that Tf-values should be complemented by a peak width measure to provide a more objective quality measure. A plan to take a further step for using Quality by Design (QbD) related to analytical methods will also be presented [Ref 1]. Continuous improvement of an original HPLC method to an UHPLC method will be the used as a case study. The capability of the two methods will be deeply studied using mechanistic comparisons. Method criteria that must be fulfilled for the two chromatographic methods will be stated. [1] 2012 PDA Europe Workshop Quality by Design The Role of Analytical Science in Implementing QbD − Technical and Regulatory Aspects, Liverpool UK 6-7 March. This is an industrial – academic cooperation in the Fundamental Separation S
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| 44. |
- Forouzanfar, Mohammad H, et al.
(författare)
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Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks in 188 countries, 1990-2013 : a systematic analysis for the Global Burden of Disease Study 2013.
- 2015
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Ingår i: The Lancet. - 0140-6736 .- 1474-547X. ; 386:10010, s. 2287-2323
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The Global Burden of Disease, Injuries, and Risk Factor study 2013 (GBD 2013) is the first of a series of annual updates of the GBD. Risk factor quantification, particularly of modifiable risk factors, can help to identify emerging threats to population health and opportunities for prevention. The GBD 2013 provides a timely opportunity to update the comparative risk assessment with new data for exposure, relative risks, and evidence on the appropriate counterfactual risk distribution.METHODS: Attributable deaths, years of life lost, years lived with disability, and disability-adjusted life-years (DALYs) have been estimated for 79 risks or clusters of risks using the GBD 2010 methods. Risk-outcome pairs meeting explicit evidence criteria were assessed for 188 countries for the period 1990-2013 by age and sex using three inputs: risk exposure, relative risks, and the theoretical minimum risk exposure level (TMREL). Risks are organised into a hierarchy with blocks of behavioural, environmental and occupational, and metabolic risks at the first level of the hierarchy. The next level in the hierarchy includes nine clusters of related risks and two individual risks, with more detail provided at levels 3 and 4 of the hierarchy. Compared with GBD 2010, six new risk factors have been added: handwashing practices, occupational exposure to trichloroethylene, childhood wasting, childhood stunting, unsafe sex, and low glomerular filtration rate. For most risks, data for exposure were synthesised with a Bayesian meta-regression method, DisMod-MR 2.0, or spatial-temporal Gaussian process regression. Relative risks were based on meta-regressions of published cohort and intervention studies. Attributable burden for clusters of risks and all risks combined took into account evidence on the mediation of some risks such as high body-mass index (BMI) through other risks such as high systolic blood pressure and high cholesterol.FINDINGS: All risks combined account for 57·2% (95% uncertainty interval [UI] 55·8-58·5) of deaths and 41·6% (40·1-43·0) of DALYs. Risks quantified account for 87·9% (86·5-89·3) of cardiovascular disease DALYs, ranging to a low of 0% for neonatal disorders and neglected tropical diseases and malaria. In terms of global DALYs in 2013, six risks or clusters of risks each caused more than 5% of DALYs: dietary risks accounting for 11·3 million deaths and 241·4 million DALYs, high systolic blood pressure for 10·4 million deaths and 208·1 million DALYs, child and maternal malnutrition for 1·7 million deaths and 176·9 million DALYs, tobacco smoke for 6·1 million deaths and 143·5 million DALYs, air pollution for 5·5 million deaths and 141·5 million DALYs, and high BMI for 4·4 million deaths and 134·0 million DALYs. Risk factor patterns vary across regions and countries and with time. In sub-Saharan Africa, the leading risk factors are child and maternal malnutrition, unsafe sex, and unsafe water, sanitation, and handwashing. In women, in nearly all countries in the Americas, north Africa, and the Middle East, and in many other high-income countries, high BMI is the leading risk factor, with high systolic blood pressure as the leading risk in most of Central and Eastern Europe and south and east Asia. For men, high systolic blood pressure or tobacco use are the leading risks in nearly all high-income countries, in north Africa and the Middle East, Europe, and Asia. For men and women, unsafe sex is the leading risk in a corridor from Kenya to South Africa.INTERPRETATION: Behavioural, environmental and occupational, and metabolic risks can explain half of global mortality and more than one-third of global DALYs providing many opportunities for prevention. Of the larger risks, the attributable burden of high BMI has increased in the past 23 years. In view of the prominence of behavioural risk factors, behavioural and social science research on interventions for these risks should be strengthened. Many prevention and primary care policy options are available now to act on key risks.FUNDING: Bill & Melinda Gates Foundation.
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| 45. |
- Fowler, Scott, et al.
(författare)
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An Empirical Evaluation of Web System Access for Smartphone Clients
- 2012
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Ingår i: Journal of Networks. - : Academy Publisher. - 1796-2056. ; 7:11, s. 1700-1713
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Tidskriftsartikel (refereegranskat)abstract
- As smartphone clients are restricted in computational power and bandwidth, it is important to minimise the overhead of transmitted messages. This paper identifies and studies methods that reduce the amount of data being transferred via wireless links between a web service client and a web service. Measurements were performed in a real environment based on a web service prototype providing public transport information for the city of Hamburg in Germany, using actual wireless links with a mobile smartphone device. REST based web services using the data exchange formats JSON, XML and Fast Infoset were evaluated against the existing SOAP based web service.
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| 46. |
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| 47. |
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| 48. |
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| 49. |
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| 50. |
- Gestrelius, Sara, et al.
(författare)
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A MILP-based heuristic for a commercial train timetabling problem
- 2017
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Ingår i: Transp. Res. Procedia. - : Elsevier BV. ; , s. 569-576, s. 569-576
-
Konferensbidrag (refereegranskat)abstract
- Using mathematical methods to support the yearly timetable planning process has many advantages. Unfortunately, the train timetabling problem for large geographical areas and many trains is intractable for optimization models alone. In this paper, we therefore present a MILP-based heuristic that has been designed to generate good-enough timetables for large geographical areas and many trains. In the incremental fix and release heuristic (IFRH), trains are added to the timetable in batches. For each batch of trains, a reduced timetable problem is solved using a mathematical integer program and CPLEX. Based on the solution, the binary variables defining meeting locations and stops are fixed, and the next batch of trains is added to the timetable. If previously fixed variables make the problem infeasible, a recovery algorithm iteratively releases fixed variables to regain feasibility. The paper also introduces a simple improvement heuristic (IH) that uses the same idea of working with batches of trains. The heuristics are tested on a real case-study from Sweden consisting of both small problem instances (approximately 300 trains and 1400 possible interactions) and large problem instances (approximately 600 trains and 5500 possible interactions). IFRH returns a feasible timetable within 30 minutes for all problem instances, and after running IH the optimality gaps are less than 5%. Meanwhile, if CPLEX is used without the heuristic framework to solve the total optimization problem, a feasible timetable is not returned within 2 hours for the large problem instances. © 2017 The Authors.
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