| 1. |
|
|
| 2. |
- Jakobsson, Gunnar
(author)
-
On Complications to Cataract Surgery
- 2015
-
Doctoral thesis (other academic/artistic)abstract
- Cataract surgery, meaning exchange of the opaque lens in the eye with an artificial lens, is nowadays one of the most successful surgical procedures ever known. It is also the most frequent surgery performed in the Western world. In Sweden alone, more than 100,000 cataract operations are performed annually. Severe complications are rare, occurring only in a few percent of the patients, but owing to the large number of surgeries even infrequent complications amount to a substantial number of patients. The aim of this thesis was to study two different complications – retinal detachment (RD) and late artificial intraocular lens (IOL) dislocation – and to analyze inflammatory mediators in the vitreous of phakic (no previous cataract surgery) and pseudophakic (previous cataract surgery with IOL) eyes. Methods: Paper I is a multicenter case-control study evaluating the incidence and outcome of RD in eyes experiencing a perioperative complication with rupture of the lens capsule. Paper II and III are studies on patients with late IOL dislocation with a retrospective and a prospective observational design respectively. In paper IV the level of inflammatory immune mediators was measured in vitreous from phakic and pseudophakic patients. Results: The risk of developing RD after cataract surgery with a capsular rupture increased more than ten fold during the three-year follow-up period. Multivariate analyzes showed an odds ratio (OR) of 14.8 for RD. Additional risk factors were male sex (OR = 8.5) and lens remnants in the vitreous (OR = 14.4). The majority (62%) of eyes experiencing RD had a poor visual outcome of 0.1 or less. In patients with late IOL dislocation the median time to repositioning surgery was 6.5 years. This interval was significantly shorter in older patients and in eyes with perioperative complications (3.2 years). Pseudoexfoliations (PXF) were present in 60% of the patients and 36% had glaucoma. The annual incidence of late IOL dislocation in the pseudophakic population was calculated to 0.05%. Repositioning of the dislocated IOL with scleral sutures and a high frequency of pars plana vitrectomy procedures resulted in few complications and 59% of the patients obtained a visual acuity of ≥0.5. In patients with IOL dislocation and glaucoma, improved intraocular pressure (IOP) control was observed. Vitreous samples revealed significantly higher and sustained levels of immune mediators in pseudophakic eyes compared to phakic eyes. Conclusions: RD following capsule rupture results in profound visual loss in the majority of patients. Late IOL dislocation requiring reconstructive surgery occurs annually in 1/2000 pseudophakic patients. Risk factors are initially complicated cataract surgery, PXF and old age. The prognosis after repositioning surgery is good and IOP control in glaucoma patients is improved. Cataract surgery and pseudophakia induce elevated and sustained levels of inflammatory immune mediators in the vitreous.
|
|
| 3. |
- Ravinet, Mark, 1986, et al.
(author)
-
Unique mitochondrial DNA lineages in Irish stickleback populations: cryptic refugium or rapid recolonization?
- 2014
-
In: Ecology and Evolution. - : Wiley. - 2045-7758. ; 4:12, s. 2488-2504
-
Journal article (peer-reviewed)abstract
- Repeated recolonization of freshwater environments following Pleistocene glaciations has played a major role in the evolution and adaptation of anadromous taxa. Located at the western fringe of Europe, Ireland and Britain were likely recolonized rapidly by anadromous fishes from the North Atlantic following the last glacial maximum (LGM). While the presence of unique mitochondrial haplotypes in Ireland suggests that a cryptic northern refugium may have played a role in recolonization, no explicit test of this hypothesis has been conducted. The three-spined stickleback is native and ubiquitous to aquatic ecosystems throughout Ireland, making it an excellent model species with which to examine the biogeographical history of anadromous fishes in the region. We used mitochondrial and microsatellite markers to examine the presence of divergent evolutionary lineages and to assess broad-scale patterns of geographical clustering among postglacially isolated populations. Our results confirm that Ireland is a region of secondary contact for divergent mitochondrial lineages and that endemic haplotypes occur in populations in Central and Southern Ireland. To test whether a putative Irish lineage arose from a cryptic Irish refugium, we used approximate Bayesian computation (ABC). However, we found no support for this hypothesis. Instead, the Irish lineage likely diverged from the European lineage as a result of postglacial isolation of freshwater populations by rising sea levels. These findings emphasize the need to rigorously test biogeographical hypothesis and contribute further evidence that postglacial processes may have shaped genetic diversity in temperate fauna.
|
|
| 4. |
- Juhlin, Greger
(author)
-
Development and Application of Laser Diagnostics for Studies of Phenomena Related to IC Engine Combustion
- 2003
-
Doctoral thesis (other academic/artistic)abstract
- Various laser diagnostic techniques have been developed and demonstrated for engine, or engine-related measurements. The experimental work is presented in Chapter 3 and in Papers I-VII. In Chapter 3, imaging of soot in a running compression-ignition (CI) is described. Four different approaches were applied with the aim of investigating the applicability of these approaches in a running engine. In Paper I, Planar Laser-Induced Fluorescence (PLIF) was applied in a running spark ignition (SI) engine for measurements of the fuel concentration and homogeneity in the vicinity of the spark gap prior to ignition. The aim was to find out how the fuel distribution influences the cycle-to-cycle variations of the engine. In Paper II, PLIF of water was applied in a running engine to investigate the influence of residual gases in the vicinity of the spark gap prior to ignition. In Paper III is reported a basic investigation of the potential of PLIF for the study of water as a marker for residual gas in engines. Special care was taken in studying the effects of a focused laser beam in combination with a two-photon transition which arises in the excitation of water at 248 nm. In Paper IV is described how a combination of PLIF and spontaneous Raman scattering can be used for simultaneous imaging of vapour and liquid phase water. In Paper V, the application of PLIF to investigate the emissions of hydrocarbons in the exhaust of small two-stroke engines is described. Cycle-resolved, 2D measurements were conducted in order to find out when, during the stroke, the hydrocarbons are emitted. Cycle-resolved spectral measurements gave information on the species emitted at different crank angle positions. In Paper VI is demonstrated how phosphor thermometry can be applied to measure the temperature of a falling water droplet. Finally, in Paper VII, phosphor thermometry was applied to perform two-dimensional surface temperature measurements in a running optically accessible engine.
|
|
| 5. |
- Rodriguez-Rojas, F., et al.
(author)
-
Oxidation behaviour of pressureless liquid-phase-sintered α-SiC with additions of 5Al2O3 + 3RE2O3 (RE = La, Nd, Y, Er, Tm, or Yb)
- 2010
-
In: Journal of the European Ceramic Society. - : Elsevier BV. - 0955-2219 .- 1873-619X. ; 30:15, s. 3209-3217
-
Journal article (peer-reviewed)abstract
- The oxidation behaviour of pressureless liquid-phase-sintered (PLPS) α-SiC was investigated as a function of the sintering additives of 5Al2O3 + 3RE2O3 (RE = La, Nd, Y, Er, Tm, or Yb) by thermogravimetry experiments in oxygen at 1075–1400 °C for up to 22 h. It was found that the oxidation is in all cases passive and protective, with kinetics governed by the arctan-rate law. This is because the PLPS SiC ceramics develop oxide scales having no cracks or open porosity and accordingly prevent the parent material from direct contact with oxygen. In addition, these oxide scales crystallize gradually during the exposure to the oxidizing atmosphere with the attendant reduction in the amorphous cross-section available for oxygen diffusion. It was also found that the rate-limiting mechanism of the oxidation is outward diffusion of RE3+ cations from the intergranular phase into the oxide scale, and that the activation energy of the oxidation increases with increasing size of the RE3+ cation. It was also observed that the oxidation of PLPS SiC increases with increasing size of the RE3+ cation, an effect that is especially marked for cation sizes above 0.9 Å because the oxidation rate becomes several orders of magnitude faster. This trend is attributable to the oxide scales being more crystalline, and containing crystals that are more refractory and amorphous residual phases that are more viscous as the size of the RE3+ cation decreases. Finally, implications for the design of PLPS SiC ceramics with superior oxidation resistance are discussed.
|
|
| 6. |
- Szabo, Attila
(author)
-
Matematikundervisning för begåvade elever – en forskningsöversikt
- 2017
-
In: Nordisk matematikkdidaktikk, NOMAD. - 1104-2176. ; 22:1, s. 21-44
-
Research review (other academic/artistic)abstract
- Artikeln redovisar de huvudsakliga pedagogiska och organisatoriska metoder relaterade till begåvade elevers matematikundervisning som fokuseras i forskningslitteraturen – även könsskillnader, motivation och matematiskt begåvade elevers sociala situation i klassrummet diskuteras. Översikten visar att det finns åtgärder – t.ex. frivillig acceleration i ämnet där undervisningen är anpassad till elevens förkunskaper och kapacitet eller arbete med utmanande uppgifter i prestationshomogena grupper – som antas ha goda effekter på begåvade elevers kunskapsutveckling i matematik. Analysen visar också att det kan uppfattas som problematiskt att vara begåvad i matematik samt att begåvade flickor upplever vissa aspekter av matematikundervisningen annorlunda jämfört med motsvarande grupp pojkar.
|
|
| 7. |
- Szabo, Attila, 1965-
(author)
-
Matematiska förmågors interaktion och det matematiska minnets roll vid lösning av matematiska problem
- 2013
-
Licentiate thesis (other academic/artistic)abstract
- The thesis deals with the interaction of mathematical abilities and the mathematical memory's role in problem-solving. To examine those phenomena, I analyzed the expression of mathematical abilities for high achieving students from upper secondary school. The study shows that the mathematical memory accounts for a relatively small proportion of time of the problem-solving process and that the mathematical memory emerges mainly during the initial phase of the process. Although the mathematical memory accounts for a small percentage of the time of the problem-solving process, the mathematical memory has a decisive role for the choice of problem-solving methods, because the students choose their solution methods in the initial phase of their problem-solving activity. The study shows that the choice of problem-solving method has significant consequences for the students' problem-solving activity; if the chosen methods did not lead to the desired outcome, so the students found it very difficult to change their initially chosen problem-solving methods. The study also shows that students who use general problem-solving methods perform better than students who use numerical methods.
|
|
| 8. |
- Bitoun, R. E., et al.
(author)
-
A methodological framework for capturing marine small-scale fisheries' contributions to the sustainable development goals
- 2024
-
In: SUSTAINABILITY SCIENCE. - 1862-4065 .- 1862-4057. ; 19, s. 1119-1137
-
Journal article (peer-reviewed)abstract
- Small-scale fisheries (SSF) receive increasing international attention for landing around 40% of global marine fisheries catches and employing millions of people globally. Their contributions to food security and poverty alleviation, especially in developing countries, make it relevant to consider them when discussing sustainable development goals (SDGs). Achieving SDGs by supporting SSF means understanding fisheries in their broader context, from the health of marine ecosystems to social and economic features such as employment, public health, culture, and the effects of global change. Social-ecological relationships in SSF are complex and poorly understood, thus challenging the identification of policies that could improve and preserve the contributions of SSF to sustainable development. Here, we developed an expert-based rapid appraisal framework to identify and characterize the relationships between SSF and SDGs. The framework serves as a diagnostic tool for identifying strengths and gaps in SSF potential in enhancing SDG achievement in data-limited situations. Our structured approach extends beyond SDG 14 and target 14.b, offering insights into SSF's contributions to 11 other SDGs. As a proof of concept, we illustrate the approach and its potential contributions in two case studies in Madagascar. The method effectively captured the multiple dimensions of the SSF through the SDG lens, providing a contextually relevant understanding of how global UN goals can be achieved locally. Further research is needed to define mechanisms for aggregating and reporting the multiple, case-specific contributions of SSF to monitor progress toward the SDGs at national and global levels.
|
|
| 9. |
- Good, Lars, 1953-
(author)
-
Anterior cruciate ligament reconstruction : Anatomic and biomechanical considerations of graft placement and fixation
- 1993
-
Doctoral thesis (other academic/artistic)abstract
- This study, comprising 7 separate papers, is concerned with the mechanical causes of graft failure after intraarticular reconstruction of the anterior cruciate ligament (ACL). The study is predominantly experimental in design, but a clinical follow-up is also included to test a causal hypothesis of secondary graft elongation.Fixations of synthetic ACL substitutes with ligament staples had low security and the maximum tolerance loads were in parity with forces generated during daily activities, while screw fixations of looped ligaments had higher load to failure than a normal ACL.A stenosis, caused by osteophyte formation, was found at the intercondylar notch less than 2 years after an ACL tear, strongly suggesting impingement and wear as a possible mechanism of ACL substitute failure. The intercondylar notch was also found to be narrowed in patients with an acute tear of the ACL compared to a normal control group, thus implying causality.A standardized technique of graft placement, using a guide to aid bone drilling, was found more accurate and reproducible in achieving desired graft insertions compared to freehand drilling. This was evaluated by a new method for detennining the graft insertion locations on the femur and tibia, using a ratio related to the sagittal depth of the condyles.The ability to restore knee kinematics from an ACL deficient state, was evaluated for a drill guided graft route and an over-the-top route. The only effect of both methods, using a dacron graft tensioned in full extension, was restoring or partially restoring the increased anterior -posterior translation.A good in vitro and in vivo correlation was found between the patterns of change in dynamic fixation distance, as measured intraoperatively with an isometer, and tension in the fixed ACL substitute. The isometry measurement could not predict the magnitude of the frnal tension due to the biological variability in soft tissue compliance.Sagittal knee stability was measured at regular intervals for 2 years on patients who had an intraarticular ACL reconstruction with a patellar tendon substitute. Increasing anterior-posterior displacement was found for all patients as a group, and more for patients with an anterior femoralligament insertion location.A standardized treatment including aided bone drilling, notch plasty, isometry measurement, and restricted postoperative rehabilitation is recommended.
|
|
| 10. |
- Schwaag-Serger, Sylvia
(author)
-
China’s 15-year plan for scientific and technological development – a critical assessment
- 2007
-
In: Asia Policy. ; :4, s. 135-164
-
Journal article (peer-reviewed)abstract
- The latest long-term plan for science and technology reflects China’s determination both to overcome growing domestic social and environmental problems through technology and to become a world leader in innovation. This latest fifteen-year plan presents no radical departure from earlier strategies and continues to define policymaking by Beijing’s strong belief that innovation can be “decreed” top-down or steered by the government. The plan relies heavily both on supply-side policies for research and education and on a technology-driven view of innovation, rather than tackling less tangible and more complex issues such as deficits in social capital, institution-building, and building an innovation-friendly environment. New features in the plan include a clear emphasis on energy, environment, and water resources. New targets in the plan to strengthen “independent” or “indigenous” innovation raise concerns abroad over the emergence of “techno-nationalism” and implications for China’s future economic openness.
|
|
