| 11. |
|
|
| 12. |
- Lannek, Joakim
(författare)
-
Stråkvis inventering av Vänerns strandvegetation : Övervakningssystem för framtida kontroll av igenväxning och vegetationsförändringar
- 2001
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Föreligande arbete utgör basen i ett kontrollprogram för att följa vegetationsutvecklingeni Vänerns strandnära områden. Tanken är att återinventeringar skall ske regelbundet medca 5 års intervall.Inventeringen har inriktats på växter av igenväxningskaraktär, d v s vedartade växter samtvass, säv och flytbladsväxter. Vegetationen har inventerats i stråk, 1 m breda och med enlängd varierande mellan ca 30 m och 150 m. Totalt har 61 stråk fördelat på 25 områdeninventerats. Områdena har valts ut i IR-flygbilder och med tanke på att de skall varalättillgängliga samt att mänsklig påverkan inte skall vara allt för stor. Områdena är avskiftande typ och exponeringsgrad. Stråkens placering och riktning inom de olika områdenaär markerade med i marken nedslagna kopparrör. Vidare är placering och riktning inmättamed GPS-mottagare i Rikets nät RT 90 och dessutom finns stråken beskrivna i bildoch text. Vid stråkinventeringen har förekommande vegetation noterats liksom dess utbredningoch avstånd från startpunkten.
|
|
| 13. |
- Lannemyr, Lukas, 1974
(författare)
-
Cardiopulmonary bypass and the kidney - studies on patients undergoing cardiac surgery
- 2018
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Acute kidney injury is a common complication after cardiac surgery with cardiopulmonary bypass (CPB), and has a major impact on morbidity, mortality and costs. The mechanism of CPB-related renal impairment is not fully understood. The aim of this thesis was to describe how CPB affects the kidneys, and whether increased CPB flow might improve renal oxygenation. In addition, we compared the systemic and renal effects of two inotropes in patients with impaired cardiac and renal function. Methods: In patients undergoing cardiac surgery we used urine measurement of N-acetyl-ß-D-glucosaminidase (NAG) to assess tubular cell injury (n=61). Renal vein catheterization was used to study renal blood flow, oxygenation, and filtration during normothermic CPB at 2.5 L/min/m2 (n=18), and at different CPB flow levels (2.4, 2.7 and 3.0 L/min/m2) applied in a randomized order (n=17). In 32 patients with cardiac and renal impairment, pulmonary artery and renal vein catheters were used to study the differential effects of levosimendan and dobutamine in a randomized blinded trial. Results: NAG was elevated already after 30 minutes of CPB, and increased to a six-fold peak early after discontinuation of CPB. In a multivariate analysis, the duration of CPB and the degree of rewarming were independent predictors of peak NAG excretion. Renal oxygenation was impaired during CPB, mainly through reduced oxygen delivery due to hemodilution and renal vasoconstriction. After CPB, renal oxygenation was further impaired due to increased oxygen consumption and inefficient sodium transport. At higher than normal CPB flow rates, renal oxygen extraction was reduced by 12–23 % at an unchanged filtration fraction, indicating that renal oxygenation was improved. In contrast to dobutamine, levosimendan did not only increase cardiac output and renal blood flow, but also increased the glomerular filtration rate by 22%. Conclusions: Cardiopulmonary bypass impairs renal oxygenation due to renal vasoconstriction and hemodilution during and after cardiopulmonary bypass, accompanied by increased release of a tubular injury marker. The postoperative tubular injury is increased after longer CPB times and higher degree of rewarming. Increasing the CPB flow rate may ameliorate the impaired oxygenation seen during CPB. In patients with heart failure and renal impairment, levosimendan may be the inotrope of choice.
|
|
| 14. |
- Lannemyr, Lukas, 1974, et al.
(författare)
-
Effects of milrinone on renal perfusion, filtration and oxygenation in patients with acute heart failure and low cardiac output early after cardiac surgery
- 2020
-
Ingår i: Journal of Critical Care. - : Elsevier BV. - 0883-9441. ; 57, s. 225-230
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: Early postoperative heart failure is common after cardiac surgery, and inotrope treatment may impact renal perfusion and oxygenation. We aimed to study the renal effects of the inodilator milrinone when used for the treatment of heart failure after weaning from cardiopulmonary bypass (CPB). Material and methods: In 26 patients undergoing cardiac surgery with CPB, we used renal vein catheterization to prospectively measure renal blood flow (RBF), glomerular filtration rate (GFR), and renal oxygenation. Patients who developed acute heart failure and lowcardiac output (cardiac index b2.1 L/min/m2) at 30min afterweaning fromCPB (n= 7) were given milrinone, and the remaining patients (n= 19) served as controls. Additionalmeasurements were made at 60 min after CPB. Results: In patientswith acute postoperative heart failure, before receiving milrinone, renal blood flow was lower (-33%, p b.05) while renal oxygen extraction was higher (41%, p b.05) compared to the control group. Milrinone increased cardiac index (21%, p b.001), RBF (36%, p b.01) and renal oxygen delivery (35%, p b.01), with no significant change in GFR and oxygen consumption compared to the control group. Conclusions: In patients with acute heart failure after weaning from CPB, the milrinone-induced increase in cardiac output was accompanied by improved renal oxygenation. Trial registration: ClinicalTrials.gov; identifier NCT02405195, date of registration; March 27, 2015, and NCT02549066, date of registration; 9 September 2015. (c) 2020 Elsevier Inc. All rights reserved.
|
|
| 15. |
- Lannemyr, Lukas, 1974, et al.
(författare)
-
Impact of Cardiopulmonary Bypass Flow on Renal Oxygenation in Patients Undergoing Cardiac Operations
- 2019
-
Ingår i: The Annals of thoracic surgery. - : Elsevier BV. - 1552-6259 .- 0003-4975. ; 107:2, s. 505-511
-
Tidskriftsartikel (refereegranskat)abstract
- Cardiac surgery with cardiopulmonary bypass (CPB) is associated with acute kidney injury, and the risk increases with low oxygen delivery during CPB. We hypothesized that renal oxygenation could be improved at higher than normal CPB flow rates.After ethical approval and informed consent, 17 patients with normal serum creatinine undergoing normothermic CPB were included and received pulmonary artery and renal vein catheters after anesthesia induction for measurements of systemic and renal variables. Renal oxygen extraction (RO2Ex), a direct measure of the renal oxygen delivery /renal oxygen consumption ratio, and renal filtration fraction were measured, the latter by renal extraction of 51chromium-EDTA. After start of CPB and aortic cross-clamp, the pump flow rate was randomly varied between 2.4, 2.7 and 3.0 l·min-1·m-2 and measurements were made after 10 minutes at each flow rate.RO2Ex increased by 30% at a flow rate of 2.4 l·min-1·m-2 vs. pre-CPB (p<0.05). At a flow rate of 2.7 and 3.0 l·min-1·m-2, RO2Ex was 12% (p<0.05) and 23% (p<0.01) lower, respectively, compared to 2.4 l·min-1·m-2. This corresponds to a 14% and 30% improvement, respectively, of the renal oxygen supply/demand relationship. Filtration fraction was not affected by changes in flow rate, indicating that the glomerular filtration rate increased in proportion to the increase in renal perfusion.The impaired renal oxygenation seen during CPB is ameliorated by an increase in CPB flow rate. Thus, one way to protect the kidneys, during CPB, could be to use a higher flow rate than the one traditionally used.
|
|
| 16. |
- Lannen, Patrizia, et al.
(författare)
-
Absorbing information about a child's incurable cancer.
- 2010
-
Ingår i: Oncology. - : S. Karger AG. - 0030-2414 .- 1423-0232. ; 78:3-4, s. 259-266
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To assess parents' ability to absorb information that their child's cancer was incurable and to identify factors associated with parents' ability to absorb this information.PATIENTS AND METHODS: An anonymous mail-in questionnaire study was performed as a population-based investigation in Sweden between August and October of 2001. 449 parents who lost a child to cancer 4-9 years earlier (response rate 80%) completed the survey. 191 (43%) of the bereaved parents were fathers and 251 (56%) were mothers.RESULTS: Sixty percent of parents (n = 258) reported that they were able to absorb the information that their child's illness was incurable. Parents were better able to absorb this information when the information was given in an appropriate manner (RR 1.6; CI 1.3-2.0), when they shared their problems with others during the child's illness course (RR 1.4; CI 1.1-1.8) and when they had no history of depression (RR 1.3; CI 1.0-1.8). Parents who reported that they were able to absorb the information were more likely to have expressed their farewells to the child in their desired manner (RR 1.3; CI 1.0-1.5).CONCLUSIONS: Parents who received information that their child's illness was incurable in an appropriate manner are more likely to absorb that information. Whether or not parents are able to absorb the information that their child's cancer is incurable has implications in terms of preparation for the child's impending death.
|
|
| 17. |
- Lawal, Najeem, 1974-
(författare)
-
Memory Synthesis for FPGA Implementation of Real-Time Video Processing Systems
- 2006
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this thesis, both a method and a tool to enable efficient memory synthesis for real-time video processing systems on field programmable logic array are presented. In real-time video processing system (RTVPS), a set of operations are repetitively performed on every image frame in a video stream. These operations are usually computationally intensive and, depending on the video resolution, can also be very data transfer dominated. These operations, which often require data from several consecutive frames and many rows of data within each frame, must be performed accurately and under real-time constraints as the results greatly affect the accuracy of application. Application domains of these systems include object recognition, object tracking and surveillance. Developments in field programmable gate array (FPGA) have been the motivation for choosing them as the platform for implementing RTVPS. Essential logic resources required in RTVPS operation are currently available optimized and embedded in modern FPGAs. One such resource is the embedded memory used for data buffering during real-time video processing. Each data buffer corresponds to a row of pixels in a video frame, which is allocated using a synthesis tool that performs the mapping of buffers to embedded memories. This approach has been investigated and proven to be inefficient. An efficient alternative employing resource sharing and allocation width pipelining will be discussed in this thesis. A method for the optimal use of these embedded memories and, additionally, a tool supporting automatic generation of hardware descriptions language (HDL) codes for the synthesis of the memories according to the developed method are the main focus of this thesis. This method consists of the memory architecture, allocation and addressing. The central objective of this method is the optimal use of embedded memories in the process of buffering data on-chip for an RVTPS operation. The developed software tool is an environment for generating HDL codes implementing the memory sub-components. The tool integrates with the Interface and Memory Modelling (IMEM) tools in such a way that the IMEM’s output - the memory requirements of a RTVPS - is imported and processed in order to generate the HDL codes. IMEM is based on the philosophy that the memory requirements of an RTVPS can be modelled and synthesized separately from the development of the core RTVPS algorithm thus freeing the designer to focus on the development of the algorithm while relying on IMEM for the implementation of memory sub-components.
|
|
| 18. |
|
|
| 19. |
- Oskolkov, Nikolay, et al.
(författare)
-
Dimensionality Reduction : Overview, Technical Details, and Some Applications
- 2022
-
Ingår i: Applied data science in tourism : Interdisciplinary approaches, methodologies, and applications - Interdisciplinary approaches, methodologies, and applications. - Cham : Springer International Publishing. - 2366-262X .- 2366-2611. - 9783030883898 - 9783030883881 ; , s. 151-167
-
Bokkapitel (refereegranskat)abstract
- Dimensionality reduction is an Exploratory Data Analysis (EDA) approach allowing for fast visualization of high-dimensional data and the possibility of discovering hidden systematic patterns within a data set. While linear dimensionality reduction techniques, such as Principal Component Analysis (PCA), are considered the golden standard in many areas of data science, they seem to be inadequate for analyzing non-linear high-dimensional data (e.g., images, text, gene expression). Instead, in this case, non-linear dimensionality reduction with t-distributed Neighbor Embedding (tSNE) and Uniform Manifold Approximation and Projection (UMAP) have been widely used, providing state-of-the-art methods to explore high-dimensional data. This chapter will give an overview of dimension reduction techniques, with a particular focus on PCA, tSNE, and UMAP and their applications within the fields of data science and computational biology.
|
|
| 20. |
- Peltola, Pasi
(författare)
-
Multielement Urban Geochemistry : Exporing the Expected, the Unexpected and the Unknown
- 2005
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Urban areas are hot-spots for the human use of most elements. These elements are the building blocks of our various goods and chemicals and are used both purposely and in a more unaware fashion. There are many ways in which the elements get dispersed from the human use. Commonly acknowledged and evident processes of dispersion are point sources (e.g. industrial pollution), diffuse sources (e.g. traffic) and the past historic use of various chemicals. In fact everything ever produced is going to end up somewhere - it is just a matter of time. Soils and sediments are the main sinks for elements dispersed from the above and other sources. The importance of recognising the dispersion of elements lies in the well-known fact that many elements are toxic or potentially toxic. Due to the multitude of chemicals used in urban areas during time periods up to even thousand of years it can not be known exactly which elements are enriched at specific sites or in specific samples. Moreover, if the presence of a specific element is "unexpected" then it can lead to the element not being searched for (determined) at all. Due to this it is important that as many elements as possible are determined from samples with urban environmental concern. In this thesis multielement chemical analyses (mainly ICP-MS) are used to study the past, present and potential future dispersion of chemical elements, mainly in and around the small town of Jakobstad (Pietarsaari), Finland. The materials studied were till, boreal forest humus, various urban soils, street dust, lake sediments and sediment leachates. The results first of all show that multielement analytical methods are useful, if not totally necessary, in order to grasp the presence and dispersion of various elements from both natural and anthropogenic sources. This is especially important when dealing with the dispersion of toxic elements. The most important specific findings of this thesis are: the presence of reduced sulphur in natural lake sediments can lead to considerable leakage of many elements if the sediments are dredged and allowed to oxidise; that boreal forest humus can be used to track the past urban dispersion of various chemical elements; boron can be used to track wood fires from sedimentary profiles; that the use of red lead has caused extreme lead concentration in the topsoil from small-scale usage. This lead can be "invisible" and highly bioavailable to certain bacteria and most likely also to other organisms; that tungsten carbide is enriched in the urban humus and dust and dispersed to the environment from the studded tyres as < 0.1 -1.4 um particles.
|
|
